VERSION.txt: this is v1.46.1

Signed-off-by: Andrea Gottardo <andrea@tailscale.com>

.bencher/config.yaml

@@ -0,0 +1 @@
+suppress_failure_on_regression: true

.gitattributes

@@ -1 +1,2 @@
 go.mod filter=go-mod
+*.go  diff=golang

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,8 +0,0 @@
----
-name: Bug report
-about: Create a bug report
-title: ''
-labels: 'needs-triage'
-assignees: ''
-
----

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,81 @@
+name: Bug report
+description: File a bug report. If you need help, contact support instead
+labels: [needs-triage, bug]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Need help with your tailnet? [Contact support](https://tailscale.com/contact/support) instead.
+        Otherwise, please check if your bug is [already filed](https://github.com/tailscale/tailscale/issues) before filing a new one.
+  - type: textarea
+    id: what-happened
+    attributes:
+      label: What is the issue?
+      description: What happened? What did you expect to happen?
+    validations:
+      required: true
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps to reproduce
+      description: What are the steps you took that hit this issue?
+    validations:
+      required: false
+  - type: textarea
+    id: changes
+    attributes:
+      label: Are there any recent changes that introduced the issue?
+      description: If so, what are those changes?
+    validations:
+      required: false
+  - type: dropdown
+    id: os
+    attributes:
+      label: OS
+      description: What OS are you using? You may select more than one.
+      multiple: true
+      options:
+        - Linux
+        - macOS
+        - Windows
+        - iOS
+        - Android
+        - Synology
+        - Other
+    validations:
+      required: false
+  - type: input
+    id: os-version
+    attributes:
+      label: OS version
+      description: What OS version are you using?
+      placeholder: e.g., Debian 11.0, macOS Big Sur 11.6, Synology DSM 7
+    validations:
+      required: false
+  - type: input
+    id: ts-version
+    attributes:
+      label: Tailscale version
+      description: What Tailscale version are you using?
+      placeholder: e.g., 1.14.4
+    validations:
+      required: false
+  - type: textarea
+    id: other-software
+    attributes:
+      label: Other software
+      description: What [other software](https://github.com/tailscale/tailscale/wiki/OtherSoftwareInterop) (networking, security, etc) are you running?
+    validations:
+      required: false
+  - type: input
+    id: bug-report
+    attributes:
+      label: Bug report
+      description: Please run [`tailscale bugreport`](https://tailscale.com/kb/1080/cli/?q=Cli#bugreport) and share the bug identifier. The identifier is a random string which allows Tailscale support to locate your account and gives a point to focus on when looking for errors.
+      placeholder: e.g., BUG-1b7641a16971a9cd75822c0ed8043fee70ae88cf05c52981dc220eb96a5c49a8-20210427151443Z-fbcd4fd3a4b7ad94
+    validations:
+      required: false
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for filing a bug report!

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +1,8 @@
 blank_issues_enabled: true
 contact_links:
-  - name: Support and Product Questions
+  - name: Support
+    url: https://tailscale.com/contact/support/
+    about: Contact us for support
+  - name: Troubleshooting
     url: https://tailscale.com/kb/1023/troubleshooting
-    about: Please send support questions and questions about the Tailscale product to support@tailscale.com
+    about: See the troubleshooting guide for help addressing common issues

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,7 +0,0 @@
----
-name: Feature request
-about: Suggest an idea for this project
-title: ''
-labels: 'needs-triage'
-assignees: ''
----

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,42 @@
+name: Feature request
+description: Propose a new feature
+title: "FR: "
+labels: [needs-triage, fr]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Please check if your feature request is [already filed](https://github.com/tailscale/tailscale/issues).
+        Tell us about your idea!
+  - type: textarea
+    id: problem
+    attributes:
+      label: What are you trying to do?
+      description: Tell us about the problem you're trying to solve.
+    validations:
+      required: false
+  - type: textarea
+    id: solution
+    attributes:
+      label: How should we solve this?
+      description: If you have an idea of how you'd like to see this feature work, let us know.
+    validations:
+      required: false
+  - type: textarea
+    id: alternative
+    attributes:
+      label: What is the impact of not solving this?
+      description: (How) Are you currently working around the issue?
+    validations:
+      required: false
+  - type: textarea
+    id: context
+    attributes:
+      label: Anything else?
+      description: Any additional context to share, e.g., links
+    validations:
+      required: false
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for filing a feature request!

.github/dependabot.yml

@@ -0,0 +1,21 @@
+# Documentation for this file can be found at:
+# https://docs.github.com/en/code-security/supply-chain-security/keeping-your-dependencies-updated-automatically/configuration-options-for-dependency-updates
+version: 2
+updates:
+  ## Disabled between releases. We reenable it briefly after every
+  ## stable release, pull in all changes, and close it again so that
+  ## the tree remains more stable during development and the upstream
+  ## changes have time to soak before the next release.
+  # - package-ecosystem: "gomod"
+  #   directory: "/"
+  #   schedule:
+  #     interval: "daily"
+  #   commit-message:
+  #     prefix: "go.mod:"
+  #   open-pull-requests-limit: 100
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    commit-message:
+      prefix: ".github:"

.github/licenses.tmpl

@@ -0,0 +1,17 @@
+# Tailscale CLI and daemon dependencies
+
+The following open source dependencies are used to build the [tailscale][] and
+[tailscaled][] commands. These are primarily used on Linux and BSD variants as
+well as an [option for macOS][].
+
+[tailscale]: https://pkg.go.dev/tailscale.com/cmd/tailscale
+[tailscaled]: https://pkg.go.dev/tailscale.com/cmd/tailscaled
+[option for macOS]: https://tailscale.com/kb/1065/macos-variants/
+
+## Go Packages
+
+Some packages may only be included on certain architectures or operating systems.
+
+{{ range . }}
+ - [{{.Name}}](https://pkg.go.dev/{{.Name}}) ([{{.LicenseName}}]({{.LicenseURL}}))
+{{- end }}

.github/workflows/codeql-analysis.yml

@@ -0,0 +1,77 @@
+# For most projects, this workflow file will not need changing; you simply need
+# to commit it to your repository.
+#
+# You may wish to alter this file to override the set of languages analyzed,
+# or to provide custom queries or build logic.
+#
+# ******** NOTE ********
+# We have attempted to detect the languages in your repository. Please check
+# the `language` matrix defined below to confirm you have the correct set of
+# supported CodeQL languages.
+#
+name: "CodeQL"
+
+on:
+  push:
+    branches: [ main, release-branch/* ]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: [ main ]
+  merge_group:
+    branches: [ main ]
+  schedule:
+    - cron: '31 14 * * 5'
+
+concurrency:
+  group: ${{ github.workflow }}-$${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'go' ]
+        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python' ]
+        # Learn more:
+        # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v2
+      with:
+        languages: ${{ matrix.language }}
+        # If you wish to specify custom queries, you can do so here or in a config file.
+        # By default, queries listed here will override any specified in a config file.
+        # Prefix the list here with "+" to use these queries and those in the config file.
+        # queries: ./path/to/local/query, your-org/your-repo/queries@main
+
+    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
+    # If this step fails, then you should remove it and run the build manually (see below)
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v2
+
+    # ℹ️ Command-line programs to run using the OS shell.
+    # 📚 https://git.io/JvXDl
+
+    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
+    #    and modify them (or add more) to build your code if your project
+    #    uses a compiled language
+
+    #- run: |
+    #   make bootstrap
+    #   make release
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v2

.github/workflows/cross-darwin.yml

@@ -1,53 +0,0 @@
-name: Darwin-Cross
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: macOS build cmd
-      env:
-        GOOS: darwin
-        GOARCH: amd64
-      run: go build ./cmd/...
-
-    - name: macOS build tests
-      env:
-        GOOS: darwin
-        GOARCH: amd64
-      run: for d in $(go list -f '{{if .TestGoFiles}}{{.Dir}}{{end}}' ./... ); do (echo $d; cd $d && go test -c ); done
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/cross-freebsd.yml

@@ -1,53 +0,0 @@
-name: FreeBSD-Cross
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: FreeBSD build cmd
-      env:
-        GOOS: freebsd
-        GOARCH: amd64
-      run: go build ./cmd/...
-
-    - name: FreeBSD build tests
-      env:
-        GOOS: freebsd
-        GOARCH: amd64
-      run: for d in $(go list -f '{{if .TestGoFiles}}{{.Dir}}{{end}}' ./... ); do (echo $d; cd $d && go test -c ); done
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/cross-openbsd.yml

@@ -1,53 +0,0 @@
-name: OpenBSD-Cross
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: OpenBSD build cmd
-      env:
-        GOOS: openbsd
-        GOARCH: amd64
-      run: go build ./cmd/...
-
-    - name: OpenBSD build tests
-      env:
-        GOOS: openbsd
-        GOARCH: amd64
-      run: for d in $(go list -f '{{if .TestGoFiles}}{{.Dir}}{{end}}' ./... ); do (echo $d; cd $d && go test -c ); done
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/cross-windows.yml

@@ -1,53 +0,0 @@
-name: Windows-Cross
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: Windows build cmd
-      env:
-        GOOS: windows
-        GOARCH: amd64
-      run: go build ./cmd/...
-
-    - name: Windows build tests
-      env:
-        GOOS: windows
-        GOARCH: amd64
-      run: for d in $(go list -f '{{if .TestGoFiles}}{{.Dir}}{{end}}' ./... ); do (echo $d; cd $d && go test -c ); done
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/depaware.yml

@@ -1,28 +0,0 @@
-name: depaware
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    steps:
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-
-    - name: Check out code
-      uses: actions/checkout@v1
-
-    - name: depaware tailscaled
-      run: go run github.com/tailscale/depaware --check tailscale.com/cmd/tailscaled
-
-    - name: depaware tailscale
-      run: go run github.com/tailscale/depaware --check tailscale.com/cmd/tailscale

.github/workflows/docker-file-build.yml

@@ -0,0 +1,15 @@
+name: "Dockerfile build"
+on: 
+  push:
+    branches:
+    - main
+  pull_request:
+    branches:
+      - "*"
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: "Build Docker image"
+      run: docker build .

.github/workflows/go-licenses.yml

@@ -0,0 +1,64 @@
+name: go-licenses
+
+on:
+  # run action when a change lands in the main branch which updates go.mod or
+  # our license template file. Also allow manual triggering.
+  push:
+    branches:
+      - main
+    paths:
+      - go.mod
+      - .github/licenses.tmpl
+      - .github/workflows/go-licenses.yml
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-$${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  update-licenses:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v3
+
+      - name: Set up Go
+        uses: actions/setup-go@v4
+        with:
+          go-version-file: go.mod
+
+      - name: Install go-licenses
+        run: |
+          go install github.com/google/go-licenses@v1.2.2-0.20220825154955-5eedde1c6584
+
+      - name: Run go-licenses
+        env:
+          # include all build tags to include platform-specific dependencies
+          GOFLAGS: "-tags=android,cgo,darwin,freebsd,ios,js,linux,openbsd,wasm,windows"
+        run: |
+          [ -d licenses ] || mkdir licenses
+          go-licenses report tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled > licenses/tailscale.md --template .github/licenses.tmpl
+
+      - name: Get access token
+        uses: tibdex/github-app-token@b62528385c34dbc9f38e5f4225ac829252d1ea92 # v1.8.0
+        id: generate-token
+        with:
+          app_id: ${{ secrets.LICENSING_APP_ID }}
+          installation_id: ${{ secrets.LICENSING_APP_INSTALLATION_ID }}
+          private_key: ${{ secrets.LICENSING_APP_PRIVATE_KEY }}
+
+      - name: Send pull request
+        uses: peter-evans/create-pull-request@284f54f989303d2699d373481a0cfa13ad5a6666 #v5.0.1
+        with:
+          token: ${{ steps.generate-token.outputs.token }}
+          author: License Updater <noreply+license-updater@tailscale.com>
+          committer: License Updater <noreply+license-updater@tailscale.com>
+          branch: licenses/cli
+          commit-message: "licenses: update tailscale{,d} licenses"
+          title: "licenses: update tailscale{,d} licenses"
+          body: Triggered by ${{ github.repository }}@${{ github.sha }}
+          signoff: true
+          delete-branch: true
+          team-reviewers: opensource-license-reviewers

.github/workflows/go_generate.yml

@@ -1,34 +0,0 @@
-name: go generate
-
-on:
-  push:
-    branches:
-      - main
-      - "release-branch/*"
-  pull_request:
-    branches:
-      - "*"
-
-jobs:
-  check:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Set up Go
-        uses: actions/setup-go@v1
-        with:
-          go-version: 1.16
-
-      - name: Check out code
-        uses: actions/checkout@v2
-        with:
-          fetch-depth: 0
-
-      - name: check 'go generate' is clean
-        run: |
-          mkdir gentools
-          go build -o gentools/stringer golang.org/x/tools/cmd/stringer
-          PATH="$PATH:$(pwd)/gentools" go generate ./...
-          echo
-          echo
-          git diff --name-only --exit-code || (echo "The files above need updating. Please run 'go generate'."; exit 1)

.github/workflows/golangci-lint.yml

@@ -0,0 +1,40 @@
+name: golangci-lint
+on:
+  # For now, only lint pull requests, not the main branches.
+  pull_request:
+
+  # TODO(andrew): enable for main branch after an initial waiting period.
+  #push:
+  #  branches:
+  #    - main
+
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pull-requests: read
+
+concurrency:
+  group: ${{ github.workflow }}-$${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - uses: actions/setup-go@v4
+        with:
+          go-version-file: go.mod
+          cache: false
+
+      - name: golangci-lint
+        # Note: this is the 'v3' tag as of 2023-04-17
+        uses: golangci/golangci-lint-action@639cd343e1d3b897ff35927a75193d57cfcba299
+        with:
+          version: v1.52.2
+
+          # Show only new issues if it's a pull request.
+          only-new-issues: true

.github/workflows/govulncheck.yml

@@ -0,0 +1,37 @@
+name: govulncheck
+
+on:
+  schedule:
+    - cron: "0 12 * * *" # 8am EST / 10am PST / 12pm UTC
+  workflow_dispatch: # allow manual trigger for testing
+  pull_request:
+    paths:
+      - ".github/workflows/govulncheck.yml"
+
+jobs:
+  source-scan:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v3
+
+      - name: Install govulncheck
+        run: ./tool/go install golang.org/x/vuln/cmd/govulncheck@latest
+
+      - name: Scan source code for known vulnerabilities
+        run: PATH=$PWD/tool/:$PATH "$(./tool/go env GOPATH)/bin/govulncheck" -test ./...
+
+      - uses: ruby/action-slack@v3.2.1
+        with:
+          payload: >
+            {
+              "attachments": [{
+                "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks>
+                        (<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|commit>) of ${{ github.repository }}@${{ github.ref_name }} by ${{ github.event.head_commit.committer.name }}",
+                "color": "danger"
+              }]
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+        if: failure() && github.event_name == 'schedule'

.github/workflows/installer.yml

@@ -0,0 +1,102 @@
+name: test installer.sh
+
+on:
+  push:
+    branches:
+      - "main"
+    paths:
+      - scripts/installer.sh
+  pull_request:
+    branches:
+      - "*"
+    paths:
+      - scripts/installer.sh
+
+jobs:
+  test:
+    strategy:
+      # Don't abort the entire matrix if one element fails.
+      fail-fast: false
+      # Don't start all of these at once, which could saturate Github workers.
+      max-parallel: 4
+      matrix:
+        image:
+          # This is a list of Docker images against which we test our installer.
+          # If you find that some of these no longer exist, please feel free
+          # to remove them from the list.
+          # When adding new images, please only use official ones.
+          - "debian:oldstable-slim"
+          - "debian:stable-slim"
+          - "debian:testing-slim"
+          - "debian:sid-slim"
+          - "ubuntu:18.04"
+          - "ubuntu:20.04"
+          - "ubuntu:22.04"
+          - "ubuntu:22.10"
+          - "ubuntu:23.04"
+          - "elementary/docker:stable"
+          - "elementary/docker:unstable"
+          - "parrotsec/core:lts-amd64"
+          - "parrotsec/core:latest"
+          - "kalilinux/kali-rolling"
+          - "kalilinux/kali-dev"
+          - "oraclelinux:9"
+          - "oraclelinux:8"
+          - "fedora:latest"
+          - "rockylinux:8.7"
+          - "rockylinux:9"
+          - "amazonlinux:latest"
+          - "opensuse/leap:latest"
+          - "opensuse/tumbleweed:latest"
+          - "archlinux:latest"
+          - "alpine:3.14"
+          - "alpine:latest"
+          - "alpine:edge"
+        deps:
+          # Run all images installing curl as a dependency.
+          - curl
+        include:
+          # Check a few images with wget rather than curl.
+          - { image: "debian:oldstable-slim", deps: "wget" }
+          - { image: "debian:sid-slim", deps: "wget" }
+          - { image: "ubuntu:23.04", deps: "wget" }
+          # Ubuntu 16.04 also needs apt-transport-https installed.
+          - { image: "ubuntu:16.04", deps: "curl apt-transport-https" }
+          - { image: "ubuntu:16.04", deps: "wget apt-transport-https" }
+    runs-on: ubuntu-latest
+    container:
+      image: ${{ matrix.image }}
+      options: --user root
+    steps:
+    - name: install dependencies (yum)
+      # tar and gzip are needed by the actions/checkout below.
+      run: yum install -y --allowerasing tar gzip ${{ matrix.deps }}
+      if: |
+        contains(matrix.image, 'centos')
+        || contains(matrix.image, 'oraclelinux')
+        || contains(matrix.image, 'fedora')
+        || contains(matrix.image, 'amazonlinux')
+    - name: install dependencies (zypper)
+      # tar and gzip are needed by the actions/checkout below.
+      run: zypper --non-interactive install tar gzip
+      if: contains(matrix.image, 'opensuse')
+    - name: install dependencies (apt-get)
+      run: |
+        apt-get update
+        apt-get install -y ${{ matrix.deps }}
+      if: |
+        contains(matrix.image, 'debian')
+        || contains(matrix.image, 'ubuntu')
+        || contains(matrix.image, 'elementary')
+        || contains(matrix.image, 'parrotsec')
+        || contains(matrix.image, 'kalilinux')
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: run installer
+      run: scripts/installer.sh
+      # Package installation can fail in docker because systemd is not running
+      # as PID 1, so ignore errors at this step. The real check is the
+      # `tailscale --version` command below.
+      continue-on-error: true
+    - name: check tailscale version
+      run: tailscale --version

.github/workflows/license.yml

@@ -1,40 +0,0 @@
-name: license
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    steps:
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-
-    - name: Check out code
-      uses: actions/checkout@v1
-
-    - name: Run license checker
-      run: ./scripts/check_license_headers.sh .
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/linux-race.yml

@@ -1,48 +0,0 @@
-name: Linux race
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: Basic build
-      run: go build ./cmd/...
-
-    - name: Run tests and benchmarks with -race flag on linux
-      run: go test -race -bench=. -benchtime=1x ./...
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'
-

.github/workflows/linux.yml

@@ -1,48 +0,0 @@
-name: Linux
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: Basic build
-      run: go build ./cmd/...
-
-    - name: Run tests on linux
-      run: go test -bench=. -benchtime=1x ./...
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'
-

.github/workflows/linux32.yml

@@ -1,48 +0,0 @@
-name: Linux 32-bit
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-      id: go
-
-    - name: Check out code into the Go module directory
-      uses: actions/checkout@v1
-
-    - name: Basic build
-      run: GOARCH=386 go build ./cmd/...
-
-    - name: Run tests on linux
-      run: GOARCH=386 go test -bench=. -benchtime=1x ./...
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'
-

.github/workflows/staticcheck.yml

@@ -1,58 +0,0 @@
-name: staticcheck
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-
-    steps:
-    - name: Set up Go
-      uses: actions/setup-go@v1
-      with:
-        go-version: 1.16
-
-    - name: Check out code
-      uses: actions/checkout@v1
-
-    - name: Run go vet
-      run: go vet ./...
-
-    - name: Install staticcheck
-      run: "GOBIN=~/.local/bin go install honnef.co/go/tools/cmd/staticcheck"
-
-    - name: Print staticcheck version
-      run: "staticcheck -version"
-
-    - name: Run staticcheck (linux/amd64)
-      run: "GOOS=linux GOARCH=amd64 staticcheck -- $(go list ./... | grep -v tempfork)"
-
-    - name: Run staticcheck (darwin/amd64)
-      run: "GOOS=darwin GOARCH=amd64 staticcheck -- $(go list ./... | grep -v tempfork)"
-
-    - name: Run staticcheck (windows/amd64)
-      run: "GOOS=windows GOARCH=amd64 staticcheck -- $(go list ./... | grep -v tempfork)"
-
-    - name: Run staticcheck (windows/386)
-      run: "GOOS=windows GOARCH=386 staticcheck -- $(go list ./... | grep -v tempfork)"
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'

.github/workflows/test.yml

@@ -0,0 +1,500 @@
+# This is our main "CI tests" workflow. It runs everything that should run on
+# both PRs and merged commits, and for the latter reports failures to slack.
+name: CI
+
+env:
+  # Our fuzz job, powered by OSS-Fuzz, fails periodically because we upgrade to
+  # new Go versions very eagerly. OSS-Fuzz is a little more conservative, and
+  # ends up being unable to compile our code.
+  #
+  # When this happens, we want to disable the fuzz target until OSS-Fuzz catches
+  # up. However, we also don't want to forget to turn it back on when OSS-Fuzz
+  # can once again build our code.
+  #
+  # This variable toggles the fuzz job between two modes:
+  #  - false: we expect fuzzing to be happy, and should report failure if it's not.
+  #  - true: we expect fuzzing is broken, and should report failure if it start working.
+  TS_FUZZ_CURRENTLY_BROKEN: false
+
+on:
+  push:
+    branches:
+      - "main"
+      - "release-branch/*"
+  pull_request:
+    branches:
+      - "*"
+  merge_group:
+    branches:
+      - "main"
+
+concurrency:
+  # For PRs, later CI runs preempt previous ones. e.g. a force push on a PR
+  # cancels running CI jobs and starts all new ones.
+  #
+  # For non-PR pushes, concurrency.group needs to be unique for every distinct
+  # CI run we want to have happen. Use run_id, which in practice means all
+  # non-PR CI runs will be allowed to run without preempting each other.
+  group: ${{ github.workflow }}-$${{ github.pull_request.number || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    strategy:
+      fail-fast: false # don't abort the entire matrix if one element fails
+      matrix:
+        include:
+          - goarch: amd64
+          - goarch: amd64
+            buildflags: "-race"
+          - goarch: "386" # thanks yaml
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: Restore Cache
+      uses: actions/cache@v3
+      with:
+        # Note: unlike the other setups, this is only grabbing the mod download
+        # cache, rather than the whole mod directory, as the download cache
+        # contains zips that can be unpacked in parallel faster than they can be
+        # fetched and extracted by tar
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod/cache
+          ~\AppData\Local\go-build
+        # The -2- here should be incremented when the scheme of data to be
+        # cached changes (e.g. path above changes).
+        key: ${{ github.job }}-${{ runner.os }}-${{ matrix.goarch }}-${{ matrix.buildflags }}-go-2-${{ hashFiles('**/go.sum') }}-${{ github.run_id }}
+        restore-keys: |
+          ${{ github.job }}-${{ runner.os }}-${{ matrix.goarch }}-${{ matrix.buildflags }}-go-2-${{ hashFiles('**/go.sum') }}
+          ${{ github.job }}-${{ runner.os }}-${{ matrix.goarch }}-${{ matrix.buildflags }}-go-2-
+    - name: build all
+      run: ./tool/go build ${{matrix.buildflags}} ./...
+      env:
+        GOARCH: ${{ matrix.goarch }}
+    - name: build variant CLIs
+      run: |
+        export TS_USE_TOOLCHAIN=1
+        ./build_dist.sh --extra-small ./cmd/tailscaled
+        ./build_dist.sh --box ./cmd/tailscaled
+        ./build_dist.sh --extra-small --box ./cmd/tailscaled
+        rm -f tailscaled
+      env:
+        GOARCH: ${{ matrix.goarch }}
+    - name: get qemu # for tstest/archtest
+      if: matrix.goarch == 'amd64' && matrix.variant == ''
+      run: |
+        sudo apt-get -y update
+        sudo apt-get -y install qemu-user
+    - name: build test wrapper
+      run: ./tool/go build -o /tmp/testwrapper ./cmd/testwrapper
+    - name: test all
+      run: PATH=$PWD/tool:$PATH /tmp/testwrapper ./... ${{matrix.buildflags}}
+      env:
+        GOARCH: ${{ matrix.goarch }}
+    - name: bench all
+      run: PATH=$PWD/tool:$PATH /tmp/testwrapper ./... ${{matrix.buildflags}} -bench=. -benchtime=1x -run=^$ 
+      env:
+        GOARCH: ${{ matrix.goarch }}
+    - name: check that no tracked files changed
+      run: git diff --no-ext-diff --name-only --exit-code || (echo "Build/test modified the files above."; exit 1)
+    - name: check that no new files were added
+      run: |
+        # Note: The "error: pathspec..." you see below is normal!
+        # In the success case in which there are no new untracked files,
+        # git ls-files complains about the pathspec not matching anything.
+        # That's OK. It's not worth the effort to suppress. Please ignore it.
+        if git ls-files --others --exclude-standard --directory --no-empty-directory --error-unmatch -- ':/*'
+        then
+          echo "Build/test created untracked files in the repo (file names above)."
+          exit 1
+        fi
+
+  windows:
+    runs-on: windows-2022
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+
+    - name: Install Go
+      uses: actions/setup-go@v4
+      with:
+        go-version-file: go.mod
+        cache: false
+
+    - name: Restore Cache
+      uses: actions/cache@v3
+      with:
+        # Note: unlike the other setups, this is only grabbing the mod download
+        # cache, rather than the whole mod directory, as the download cache
+        # contains zips that can be unpacked in parallel faster than they can be
+        # fetched and extracted by tar
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod/cache
+          ~\AppData\Local\go-build
+        # The -2- here should be incremented when the scheme of data to be
+        # cached changes (e.g. path above changes).
+        key: ${{ github.job }}-${{ runner.os }}-go-2-${{ hashFiles('**/go.sum') }}-${{ github.run_id }}
+        restore-keys: |
+          ${{ github.job }}-${{ runner.os }}-go-2-${{ hashFiles('**/go.sum') }}
+          ${{ github.job }}-${{ runner.os }}-go-2-
+    - name: test
+      # Don't use -bench=. -benchtime=1x.
+      # Somewhere in the layers (powershell?)
+      # the equals signs cause great confusion.
+      run: go test -bench . -benchtime 1x ./...
+
+  vm:
+    runs-on: ["self-hosted", "linux", "vm"]
+    # VM tests run with some privileges, don't let them run on 3p PRs.
+    if: github.repository == 'tailscale/tailscale'
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: Run VM tests
+      run: ./tool/go test ./tstest/integration/vms -v -no-s3 -run-vm-tests -run=TestRunUbuntu2004
+      env:
+        HOME: "/tmp"
+        TMPDIR: "/tmp"
+        XDB_CACHE_HOME: "/var/lib/ghrunner/cache"
+  
+  cross: # cross-compile checks, build only.
+    strategy:
+      fail-fast: false # don't abort the entire matrix if one element fails
+      matrix:
+        include:
+          # Note: linux/amd64 is not in this matrix, because that goos/goarch is
+          # tested more exhaustively in the 'test' job above.
+          - goos: linux
+            goarch: arm64
+          - goos: linux
+            goarch: "386" # thanks yaml
+          - goos: linux
+            goarch: loong64
+          - goos: linux
+            goarch: arm
+            goarm: "5"
+          - goos: linux
+            goarch: arm
+            goarm: "7"
+          # macOS
+          - goos: darwin
+            goarch: amd64
+          - goos: darwin
+            goarch: arm64
+          # Windows
+          - goos: windows
+            goarch: amd64
+          - goos: windows
+            goarch: arm64
+          # BSDs
+          - goos: freebsd
+            goarch: amd64
+          - goos: openbsd
+            goarch: amd64
+
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: Restore Cache
+      uses: actions/cache@v3
+      with:
+        # Note: unlike the other setups, this is only grabbing the mod download
+        # cache, rather than the whole mod directory, as the download cache
+        # contains zips that can be unpacked in parallel faster than they can be
+        # fetched and extracted by tar
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod/cache
+          ~\AppData\Local\go-build
+        # The -2- here should be incremented when the scheme of data to be
+        # cached changes (e.g. path above changes).
+        key: ${{ github.job }}-${{ runner.os }}-${{ matrix.goos }}-${{ matrix.goarch }}-go-2-${{ hashFiles('**/go.sum') }}-${{ github.run_id }}
+        restore-keys: |
+          ${{ github.job }}-${{ runner.os }}-${{ matrix.goos }}-${{ matrix.goarch }}-go-2-${{ hashFiles('**/go.sum') }}
+          ${{ github.job }}-${{ runner.os }}-${{ matrix.goos }}-${{ matrix.goarch }}-go-2-
+    - name: build all
+      run: ./tool/go build ./cmd/...
+      env:
+        GOOS: ${{ matrix.goos }}
+        GOARCH: ${{ matrix.goarch }}
+        GOARM: ${{ matrix.goarm }}
+        CGO_ENABLED: "0"
+    - name: build tests
+      run: ./tool/go test -exec=true ./...
+      env:
+        GOOS: ${{ matrix.goos }}
+        GOARCH: ${{ matrix.goarch }}
+        CGO_ENABLED: "0"
+
+  ios: # similar to cross above, but iOS can't build most of the repo. So, just
+       #make it build a few smoke packages.
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: build some
+      run: ./tool/go build ./ipn/... ./wgengine/ ./types/... ./control/controlclient
+      env:
+        GOOS: ios
+        GOARCH: arm64
+
+  android:
+    # similar to cross above, but android fails to build a few pieces of the
+    # repo. We should fix those pieces, they're small, but as a stepping stone,
+    # only test the subset of android that our past smoke test checked.
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+      # Super minimal Android build that doesn't even use CGO and doesn't build everything that's needed
+      # and is only arm64. But it's a smoke build: it's not meant to catch everything. But it'll catch
+      # some Android breakages early.
+      # TODO(bradfitz): better; see https://github.com/tailscale/tailscale/issues/4482
+    - name: build some
+      run: ./tool/go install ./net/netns ./ipn/ipnlocal ./wgengine/magicsock/ ./wgengine/ ./wgengine/router/ ./wgengine/netstack ./util/dnsname/ ./ipn/ ./net/interfaces ./wgengine/router/ ./tailcfg/ ./types/logger/ ./net/dns ./hostinfo ./version
+      env:
+        GOOS: android
+        GOARCH: arm64
+
+  wasm: # builds tsconnect, which is the only wasm build we support
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: Restore Cache
+      uses: actions/cache@v3
+      with:
+        # Note: unlike the other setups, this is only grabbing the mod download
+        # cache, rather than the whole mod directory, as the download cache
+        # contains zips that can be unpacked in parallel faster than they can be
+        # fetched and extracted by tar
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod/cache
+          ~\AppData\Local\go-build
+        # The -2- here should be incremented when the scheme of data to be
+        # cached changes (e.g. path above changes).
+        key: ${{ github.job }}-${{ runner.os }}-go-2-${{ hashFiles('**/go.sum') }}-${{ github.run_id }}
+        restore-keys: |
+          ${{ github.job }}-${{ runner.os }}-go-2-${{ hashFiles('**/go.sum') }}
+          ${{ github.job }}-${{ runner.os }}-go-2-
+    - name: build tsconnect client
+      run: ./tool/go build ./cmd/tsconnect/wasm ./cmd/tailscale/cli
+      env:
+        GOOS: js
+        GOARCH: wasm
+    - name: build tsconnect server
+      # Note, no GOOS/GOARCH in env on this build step, we're running a build
+      # tool that handles the build itself.
+      run: |
+        ./tool/go run ./cmd/tsconnect --fast-compression build
+        ./tool/go run ./cmd/tsconnect --fast-compression build-pkg
+
+  tailscale_go: # Subset of tests that depend on our custom Go toolchain.
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: test tailscale_go
+      run: ./tool/go test -tags=tailscale_go,ts_enable_sockstats ./net/sockstats/...
+
+
+  fuzz:
+    # This target periodically breaks (see TS_FUZZ_CURRENTLY_BROKEN at the top
+    # of the file), so it's more complex than usual: the 'build fuzzers' step
+    # might fail, and depending on the value of 'TS_FUZZ_CURRENTLY_BROKEN', that
+    # might or might not be fine. The steps after the build figure out whether
+    # the success/failure is expected, and appropriately pass/fail the job
+    # overall accordingly.
+    #
+    # Practically, this means that all steps after 'build fuzzers' must have an
+    # explicit 'if' condition, because the default condition for steps is
+    # 'success()', meaning "only run this if no previous steps failed".
+    if: github.event_name == 'pull_request'
+    runs-on: ubuntu-22.04
+    steps:
+    - name: build fuzzers
+      id: build
+      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
+      # continue-on-error makes steps.build.conclusion be 'success' even if
+      # steps.build.outcome is 'failure'. This means this step does not
+      # contribute to the job's overall pass/fail evaluation.
+      continue-on-error: true
+      with:
+       oss-fuzz-project-name: 'tailscale'
+       dry-run: false
+       language: go
+    - name: report unexpectedly broken fuzz build
+      if: steps.build.outcome == 'failure' && env.TS_FUZZ_CURRENTLY_BROKEN != 'true'
+      run: |
+        echo "fuzzer build failed, see above for why"
+        echo "if the failure is due to OSS-Fuzz not being on the latest Go yet,"
+        echo "set TS_FUZZ_CURRENTLY_BROKEN=true in .github/workflows/test.yml"
+        echo "to temporarily disable fuzzing until OSS-Fuzz works again."
+        exit 1
+    - name: report unexpectedly working fuzz build
+      if: steps.build.outcome == 'success' && env.TS_FUZZ_CURRENTLY_BROKEN == 'true'
+      run: |
+        echo "fuzzer build succeeded, but we expect it to be broken"
+        echo "please set TS_FUZZ_CURRENTLY_BROKEN=false in .github/workflows/test.yml"
+        echo "to reenable fuzz testing"
+        exit 1
+    - name: run fuzzers
+      id: run
+      # Run the fuzzers whenever they're able to build, even if we're going to
+      # report a failure because TS_FUZZ_CURRENTLY_BROKEN is set to the wrong
+      # value.
+      if: steps.build.outcome == 'success'
+      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
+      with:
+        oss-fuzz-project-name: 'tailscale'
+        fuzz-seconds: 300
+        dry-run: false
+        language: go
+    - name: upload crash
+      uses: actions/upload-artifact@v3
+      if: steps.run.outcome != 'success' && steps.build.outcome == 'success'
+      with:
+        name: artifacts
+        path: ./out/artifacts
+
+  depaware:
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: check depaware
+      run: |
+        export PATH=$(./tool/go env GOROOT)/bin:$PATH
+        find . -name 'depaware.txt' | xargs -n1 dirname | xargs ./tool/go run github.com/tailscale/depaware --check
+
+  go_generate:
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: check that 'go generate' is clean
+      run: |
+        pkgs=$(./tool/go list ./... | grep -v dnsfallback)
+        ./tool/go generate $pkgs
+        echo
+        echo
+        git diff --name-only --exit-code || (echo "The files above need updating. Please run 'go generate'."; exit 1)
+
+  go_mod_tidy:
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: check that 'go mod tidy' is clean
+      run: |
+        ./tool/go mod tidy
+        echo
+        echo
+        git diff --name-only --exit-code || (echo "Please run 'go mod tidy'."; exit 1)
+
+  licenses:
+    runs-on: ubuntu-22.04
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: check licenses
+      run: ./scripts/check_license_headers.sh .
+
+  staticcheck:
+    runs-on: ubuntu-22.04
+    strategy:
+      fail-fast: false # don't abort the entire matrix if one element fails
+      matrix:
+        goos: ["linux", "windows", "darwin"]
+        goarch: ["amd64"]
+        include:
+          - goos: "windows"
+            goarch: "386"
+    steps:
+    - name: checkout
+      uses: actions/checkout@v3
+    - name: install staticcheck
+      run: GOBIN=~/.local/bin ./tool/go install honnef.co/go/tools/cmd/staticcheck
+    - name: run staticcheck
+      run: |
+        export GOROOT=$(./tool/go env GOROOT)
+        export PATH=$GOROOT/bin:$PATH
+        staticcheck -- $(./tool/go list ./... | grep -v tempfork)
+      env:
+        GOOS: ${{ matrix.goos }}
+        GOARCH: ${{ matrix.goarch }}
+
+  notify_slack:
+    if: always()
+    # Any of these jobs failing causes a slack notification.
+    needs: 
+      - android
+      - test
+      - windows
+      - vm
+      - cross
+      - ios
+      - wasm
+      - tailscale_go
+      - fuzz
+      - depaware
+      - go_generate
+      - go_mod_tidy
+      - licenses
+      - staticcheck
+    runs-on: ubuntu-22.04
+    steps:
+    - name: notify  
+      # Only notify slack for merged commits, not PR failures.
+      #
+      # It may be tempting to move this condition into the job's 'if' block, but
+      # don't: Github only collapses the test list into "everything is OK" if
+      # all jobs succeeded. A skipped job results in the list staying expanded.
+      # By having the job always run, but skipping its only step as needed, we
+      # let the CI output collapse nicely in PRs.
+      if: failure() && github.event_name == 'push'
+      uses: ruby/action-slack@v3.2.1
+      with:
+        payload: |
+          {
+            "attachments": [{
+              "title": "Failure: ${{ github.workflow }}",
+              "title_link": "https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks",         
+              "text": "${{ github.repository }}@${{ github.ref_name }}: <https://github.com/${{ github.repository }}/commit/${{ github.sha }}|${{ github.sha }}>",
+              "fields": [{ "value": ${{ toJson(github.event.head_commit.message) }}, "short": false }],
+              "footer": "${{ github.event.head_commit.committer.name }} at ${{ github.event.head_commit.timestamp }}",
+              "color": "danger"
+            }]
+          }
+      env:
+        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+
+  check_mergeability:
+    if: always()
+    runs-on: ubuntu-22.04
+    needs:
+      - android
+      - test
+      - windows
+      - vm
+      - cross
+      - ios
+      - wasm
+      - tailscale_go
+      - fuzz
+      - depaware
+      - go_generate
+      - go_mod_tidy
+      - licenses
+      - staticcheck
+    steps:
+    - name: Decide if change is okay to merge
+      if: github.event_name != 'push'
+      uses: re-actors/alls-green@release/v1
+      with:
+        jobs: ${{ toJSON(needs) }}

.github/workflows/update-flake.yml

@@ -0,0 +1,49 @@
+name: update-flake
+
+on:
+  # run action when a change lands in the main branch which updates go.mod. Also
+  # allow manual triggering.
+  push:
+    branches:
+      - main
+    paths:
+      - go.mod
+      - .github/workflows/update-flakes.yml
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-$${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  update-flake:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v3
+
+      - name: Run update-flakes
+        run: ./update-flake.sh
+
+      - name: Get access token
+        uses: tibdex/github-app-token@b62528385c34dbc9f38e5f4225ac829252d1ea92 # v1.8.0
+        id: generate-token
+        with:
+          app_id: ${{ secrets.LICENSING_APP_ID }}
+          installation_id: ${{ secrets.LICENSING_APP_INSTALLATION_ID }}
+          private_key: ${{ secrets.LICENSING_APP_PRIVATE_KEY }}
+
+      - name: Send pull request
+        uses: peter-evans/create-pull-request@284f54f989303d2699d373481a0cfa13ad5a6666 #v5.0.1
+        with:
+          token: ${{ steps.generate-token.outputs.token }}
+          author: Flakes Updater <noreply+flakes-updater@tailscale.com>
+          committer: Flakes Updater <noreply+flakes-updater@tailscale.com>
+          branch: flakes
+          commit-message: "go.mod.sri: update SRI hash for go.mod changes"
+          title: "go.mod.sri: update SRI hash for go.mod changes"
+          body: Triggered by ${{ github.repository }}@${{ github.sha }}
+          signoff: true
+          delete-branch: true
+          reviewers: danderson

.github/workflows/windows-race.yml

@@ -1,55 +0,0 @@
-name: Windows race
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  test:
-    runs-on: windows-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Install Go
-      uses: actions/setup-go@v2
-      with:
-        go-version: 1.16.x
-
-    - name: Checkout code
-      uses: actions/checkout@v2
-
-    - name: Restore Cache
-      uses: actions/cache@v2
-      with:
-        path: ~/go/pkg/mod
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-        restore-keys: |
-          ${{ runner.os }}-go-
-
-    - name: Test with -race flag
-      # Don't use -bench=. -benchtime=1x.
-      # Somewhere in the layers (powershell?)
-      # the equals signs cause great confusion.
-      run: go test -race -bench . -benchtime 1x ./...
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'
-

.github/workflows/windows.yml

@@ -1,55 +0,0 @@
-name: Windows
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - '*'
-
-jobs:
-  test:
-    runs-on: windows-latest
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-
-    - name: Install Go
-      uses: actions/setup-go@v2
-      with:
-        go-version: 1.16.x
-
-    - name: Checkout code
-      uses: actions/checkout@v2
-
-    - name: Restore Cache
-      uses: actions/cache@v2
-      with:
-        path: ~/go/pkg/mod
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-        restore-keys: |
-          ${{ runner.os }}-go-
-
-    - name: Test
-      # Don't use -bench=. -benchtime=1x.
-      # Somewhere in the layers (powershell?)
-      # the equals signs cause great confusion.
-      run: go test -bench . -benchtime 1x ./...
-
-    - uses: k0kubun/action-slack@v2.0.0
-      with:
-        payload: |
-          {
-            "attachments": [{
-              "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                      "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                      "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-              "color": "danger"
-            }]
-          }
-      env:
-        SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-      if: failure() && github.event_name == 'push'
-

.github/workflows/xe-experimental-vm-test.yml

@@ -1,45 +0,0 @@
-name: "integration-vms"
-
-on:
-  pull_request:
-    paths:
-      - "tstest/integration/vms/**"
-  release:
-    types: [ created ]
-
-jobs:
-  experimental-linux-vm-test:
-    # To set up a new runner, see tstest/integration/vms/runner.nix
-    runs-on: [ self-hosted, linux, vm_integration_test ]
-
-    if: "!contains(github.event.head_commit.message, '[ci skip]')"
-
-    steps:
-      - name: Checkout Code
-        uses: actions/checkout@v1
-
-      - name: Download VM Images
-        run: go test ./tstest/integration/vms -run-vm-tests -run=Download -timeout=60m -no-s3
-        env:
-          XDG_CACHE_HOME: "/var/lib/ghrunner/cache"
-
-      - name: Run VM tests
-        run: go test ./tstest/integration/vms -v -run-vm-tests
-        env:
-          TMPDIR: "/tmp"
-          XDG_CACHE_HOME: "/var/lib/ghrunner/cache"
-
-      - uses: k0kubun/action-slack@v2.0.0
-        with:
-          payload: |
-            {
-              "attachments": [{
-                "text": "${{ job.status }}: ${{ github.workflow }} <https://github.com/${{ github.repository }}/commit/${{ github.sha }}/checks|${{ env.COMMIT_DATE }} #${{ env.COMMIT_NUMBER_OF_DAY }}> " +
-                        "(<https://github.com/${{ github.repository }}/commit/${{ github.sha }}|" + "${{ github.sha }}".substring(0, 10) + ">) " +
-                        "of ${{ github.repository }}@" + "${{ github.ref }}".split('/').reverse()[0] + " by ${{ github.event.head_commit.committer.name }}",
-                "color": "danger"
-              }]
-            }
-        env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-        if: failure() && github.event_name == 'push'

.gitignore

@@ -5,6 +5,7 @@
 *.dll
 *.so
 *.dylib
+*.spk
 
 cmd/tailscale/tailscale
 cmd/tailscaled/tailscaled
@@ -21,3 +22,18 @@ cmd/tailscaled/tailscaled
 # direnv config, this may be different for other people so it's probably safer
 # to make this nonspecific.
 .envrc
+
+# Ignore personal VS Code settings
+.vscode/
+
+# Support personal project-specific GOPATH
+.gopath/
+
+# Ignore nix build result path
+/result
+
+# Ignore direnv nix-shell environment cache
+.direnv/
+
+/gocross
+/dist

.golangci.yml

@@ -0,0 +1,61 @@
+linters:
+  # Don't enable any linters by default; just the ones that we explicitly
+  # enable in the list below.
+  disable-all: true
+  enable:
+    - bidichk
+    - gofmt
+    - goimports
+    - misspell
+    - revive
+
+# Configuration for how we run golangci-lint
+run:
+  timeout: 5m
+
+issues:
+  # Excluding configuration per-path, per-linter, per-text and per-source
+  exclude-rules:
+    # These are forks of an upstream package and thus are exempt from stylistic
+    # changes that would make pulling in upstream changes harder.
+    - path: tempfork/.*\.go
+      text: "File is not `gofmt`-ed with `-s` `-r 'interface{} -> any'`"
+    - path: util/singleflight/.*\.go
+      text: "File is not `gofmt`-ed with `-s` `-r 'interface{} -> any'`"
+
+# Per-linter settings are contained in this top-level key
+linters-settings:
+  # Enable all rules by default; we don't use invisible unicode runes.
+  bidichk:
+
+  gofmt:
+    rewrite-rules:
+      - pattern: 'interface{}'
+        replacement: 'any'
+
+  goimports:
+
+  misspell:
+
+  revive:
+    enable-all-rules: false
+    ignore-generated-header: true
+    rules:
+      - name: atomic
+      - name: context-keys-type
+      - name: defer
+        arguments: [[
+          # Calling 'recover' at the time a defer is registered (i.e. "defer recover()") has no effect.
+          "immediate-recover",
+          # Calling 'recover' outside of a deferred function has no effect
+          "recover",
+          # Returning values from a deferred function has no effect
+          "return",
+        ]]
+      - name: duplicated-imports
+      - name: errorf
+      - name: string-of-int
+      - name: time-equal
+      - name: unconditional-recursion
+      - name: useless-break
+      - name: waitgroup-by-value

ALPINE.txt

@@ -0,0 +1 @@
+3.16

Dockerfile

@@ -1,20 +1,13 @@
-# Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-# Use of this source code is governed by a BSD-style
-# license that can be found in the LICENSE file.
+# Copyright (c) Tailscale Inc & AUTHORS
+# SPDX-License-Identifier: BSD-3-Clause
 
 ############################################################################
 #
-# WARNING: Tailscale is not yet officially supported in Docker,
-# Kubernetes, etc.
+# WARNING: Tailscale is not yet officially supported in container
+# environments, such as Docker and Kubernetes. Though it should work, we
+# don't regularly test it, and we know there are some feature limitations.
 #
-# It might work, but we don't regularly test it, and it's not as polished as
-# our currently supported platforms. This is provided for people who know
-# how Tailscale works and what they're doing.
-#
-# Our tracking bug for officially support container use cases is:
-#    https://github.com/tailscale/tailscale/issues/504
-#
-# Also, see the various bugs tagged "containers":
+# See current bugs tagged "containers":
 #    https://github.com/tailscale/tailscale/labels/containers
 #
 ############################################################################
@@ -23,11 +16,11 @@
 #
 # To build the Dockerfile:
 #
-#     $ docker build -t tailscale:tailscale .
+#     $ docker build -t tailscale/tailscale .
 #
 # To run the tailscaled agent:
 #
-#     $ docker run -d --name=tailscaled -v /var/lib:/var/lib -v /dev/net/tun:/dev/net/tun --network=host --privileged tailscale:tailscale tailscaled
+#     $ docker run -d --name=tailscaled -v /var/lib:/var/lib -v /dev/net/tun:/dev/net/tun --network=host --privileged tailscale/tailscale tailscaled
 #
 # To then log in:
 #
@@ -38,13 +31,24 @@
 #     $ docker exec tailscaled tailscale status
 
 
-FROM golang:1.16-alpine AS build-env
+FROM golang:1.20-alpine AS build-env
 
 WORKDIR /go/src/tailscale
 
 COPY go.mod go.sum ./
 RUN go mod download
 
+# Pre-build some stuff before the following COPY line invalidates the Docker cache.
+RUN go install \
+    github.com/aws/aws-sdk-go-v2/aws \
+    github.com/aws/aws-sdk-go-v2/config \
+    gvisor.dev/gvisor/pkg/tcpip/adapters/gonet \
+    gvisor.dev/gvisor/pkg/tcpip/stack \
+    golang.org/x/crypto/ssh \
+    golang.org/x/crypto/acme \
+    nhooyr.io/websocket \
+    github.com/mdlayher/netlink
+
 COPY . .
 
 # see build_docker.sh
@@ -54,13 +58,18 @@ ARG VERSION_SHORT=""
 ENV VERSION_SHORT=$VERSION_SHORT
 ARG VERSION_GIT_HASH=""
 ENV VERSION_GIT_HASH=$VERSION_GIT_HASH
+ARG TARGETARCH
 
-RUN go install -tags=xversion -ldflags="\
-      -X tailscale.com/version.Long=$VERSION_LONG \
-      -X tailscale.com/version.Short=$VERSION_SHORT \
-      -X tailscale.com/version.GitCommit=$VERSION_GIT_HASH" \
-      -v ./cmd/...
+RUN GOARCH=$TARGETARCH go install -ldflags="\
+      -X tailscale.com/version.longStamp=$VERSION_LONG \
+      -X tailscale.com/version.shortStamp=$VERSION_SHORT \
+      -X tailscale.com/version.gitCommitStamp=$VERSION_GIT_HASH" \
+      -v ./cmd/tailscale ./cmd/tailscaled ./cmd/containerboot
+
+FROM alpine:3.16
+RUN apk add --no-cache ca-certificates iptables iproute2 ip6tables
 
-FROM alpine:3.11
-RUN apk add --no-cache ca-certificates iptables iproute2
 COPY --from=build-env /go/bin/* /usr/local/bin/
+# For compat with the previous run.sh, although ideally you should be
+# using build_docker.sh which sets an entrypoint for the image.
+RUN mkdir /tailscale && ln -s /usr/local/bin/containerboot /tailscale/run.sh

Dockerfile.base

@@ -0,0 +1,5 @@
+# Copyright (c) Tailscale Inc & AUTHORS
+# SPDX-License-Identifier: BSD-3-Clause
+
+FROM alpine:3.16
+RUN apk add --no-cache ca-certificates iptables iproute2 ip6tables iputils

LICENSE

@@ -1,7 +1,6 @@
 BSD 3-Clause License
 
-Copyright (c) 2020 Tailscale & AUTHORS.
-All rights reserved.
+Copyright (c) 2020 Tailscale Inc & AUTHORS.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:

Makefile

@@ -1,24 +1,83 @@
-usage:
-	echo "See Makefile"
+IMAGE_REPO ?= tailscale/tailscale
+SYNO_ARCH ?= "amd64"
+SYNO_DSM ?= "7"
 
-vet:
-	go vet ./...
+vet: ## Run go vet
+	./tool/go vet ./...
 
-updatedeps:
-	go run github.com/tailscale/depaware --update tailscale.com/cmd/tailscaled
-	go run github.com/tailscale/depaware --update tailscale.com/cmd/tailscale
+tidy: ## Run go mod tidy
+	./tool/go mod tidy
 
-depaware:
-	go run github.com/tailscale/depaware --check tailscale.com/cmd/tailscaled
-	go run github.com/tailscale/depaware --check tailscale.com/cmd/tailscale
+updatedeps: ## Update depaware deps
+	# depaware (via x/tools/go/packages) shells back to "go", so make sure the "go"
+	# it finds in its $$PATH is the right one.
+	PATH="$$(./tool/go env GOROOT)/bin:$$PATH" ./tool/go run github.com/tailscale/depaware --update \
+		tailscale.com/cmd/tailscaled \
+		tailscale.com/cmd/tailscale \
+		tailscale.com/cmd/derper
 
-buildwindows:
-	GOOS=windows GOARCH=amd64 go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
+depaware: ## Run depaware checks
+	# depaware (via x/tools/go/packages) shells back to "go", so make sure the "go"
+	# it finds in its $$PATH is the right one.
+	PATH="$$(./tool/go env GOROOT)/bin:$$PATH" ./tool/go run github.com/tailscale/depaware --check \
+		tailscale.com/cmd/tailscaled \
+		tailscale.com/cmd/tailscale \
+		tailscale.com/cmd/derper
 
-build386:
-	GOOS=linux GOARCH=386 go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
+buildwindows: ## Build tailscale CLI for windows/amd64
+	GOOS=windows GOARCH=amd64 ./tool/go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
 
-check: staticcheck vet depaware buildwindows build386
+build386: ## Build tailscale CLI for linux/386
+	GOOS=linux GOARCH=386 ./tool/go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
 
-staticcheck:
-	go run honnef.co/go/tools/cmd/staticcheck -- $$(go list ./... | grep -v tempfork)
+buildlinuxarm: ## Build tailscale CLI for linux/arm
+	GOOS=linux GOARCH=arm ./tool/go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
+
+buildwasm: ## Build tailscale CLI for js/wasm
+	GOOS=js GOARCH=wasm ./tool/go install ./cmd/tsconnect/wasm ./cmd/tailscale/cli
+
+buildlinuxloong64: ## Build tailscale CLI for linux/loong64
+	GOOS=linux GOARCH=loong64 ./tool/go install tailscale.com/cmd/tailscale tailscale.com/cmd/tailscaled
+
+buildmultiarchimage: ## Build (and optionally push) multiarch docker image
+	./build_docker.sh
+
+check: staticcheck vet depaware buildwindows build386 buildlinuxarm buildwasm ## Perform basic checks and compilation tests
+
+staticcheck: ## Run staticcheck.io checks
+	./tool/go run honnef.co/go/tools/cmd/staticcheck -- $$(./tool/go list ./... | grep -v tempfork)
+
+spk: ## Build synology package for ${SYNO_ARCH} architecture and ${SYNO_DSM} DSM version
+	./tool/go run ./cmd/dist build synology/dsm${SYNO_DSM}/${SYNO_ARCH}
+
+spkall: ## Build synology packages for all architectures and DSM versions
+	./tool/go run ./cmd/dist build synology
+
+pushspk: spk ## Push and install synology package on ${SYNO_HOST} host
+	echo "Pushing SPK to root@${SYNO_HOST} (env var SYNO_HOST) ..."
+	scp tailscale.spk root@${SYNO_HOST}:
+	ssh root@${SYNO_HOST} /usr/syno/bin/synopkg install tailscale.spk
+
+publishdevimage: ## Build and publish tailscale image to location specified by ${REPO}
+	@test -n "${REPO}" || (echo "REPO=... required; e.g. REPO=ghcr.io/${USER}/tailscale" && exit 1)
+	@test "${REPO}" != "tailscale/tailscale" || (echo "REPO=... must not be tailscale/tailscale" && exit 1)
+	@test "${REPO}" != "ghcr.io/tailscale/tailscale" || (echo "REPO=... must not be ghcr.io/tailscale/tailscale" && exit 1)
+	@test "${REPO}" != "tailscale/k8s-operator" || (echo "REPO=... must not be tailscale/k8s-operator" && exit 1)
+	@test "${REPO}" != "ghcr.io/tailscale/k8s-operator" || (echo "REPO=... must not be ghcr.io/tailscale/k8s-operator" && exit 1)
+	TAGS=latest REPOS=${REPO} PUSH=true TARGET=client ./build_docker.sh
+
+publishdevoperator: ## Build and publish k8s-operator image to location specified by ${REPO}
+	@test -n "${REPO}" || (echo "REPO=... required; e.g. REPO=ghcr.io/${USER}/tailscale" && exit 1)
+	@test "${REPO}" != "tailscale/tailscale" || (echo "REPO=... must not be tailscale/tailscale" && exit 1)
+	@test "${REPO}" != "ghcr.io/tailscale/tailscale" || (echo "REPO=... must not be ghcr.io/tailscale/tailscale" && exit 1)
+	@test "${REPO}" != "tailscale/k8s-operator" || (echo "REPO=... must not be tailscale/k8s-operator" && exit 1)
+	@test "${REPO}" != "ghcr.io/tailscale/k8s-operator" || (echo "REPO=... must not be ghcr.io/tailscale/k8s-operator" && exit 1)
+	TAGS=latest REPOS=${REPO} PUSH=true TARGET=operator ./build_docker.sh
+
+help: ## Show this help
+	@echo "\nSpecify a command. The choices are:\n"
+	@grep -hE '^[0-9a-zA-Z_-]+:.*?## .*$$' ${MAKEFILE_LIST} | awk 'BEGIN {FS = ":.*?## "}; {printf "  \033[0;36m%-20s\033[m %s\n", $$1, $$2}'
+	@echo ""
+.PHONY: help
+
+.DEFAULT_GOAL := help

README.md

@@ -6,26 +6,41 @@ Private WireGuard® networks made easy
 
 ## Overview
 
-This repository contains all the open source Tailscale client code and
-the `tailscaled` daemon and `tailscale` CLI tool. The `tailscaled`
-daemon runs primarily on Linux; it also works to varying degrees on
-FreeBSD, OpenBSD, Darwin, and Windows.
+This repository contains the majority of Tailscale's open source code.
+Notably, it includes the `tailscaled` daemon and
+the `tailscale` CLI tool. The `tailscaled` daemon runs on Linux, Windows,
+[macOS](https://tailscale.com/kb/1065/macos-variants/), and to varying degrees
+on FreeBSD and OpenBSD. The Tailscale iOS and Android apps use this repo's
+code, but this repo doesn't contain the mobile GUI code.
 
-The Android app is at https://github.com/tailscale/tailscale-android
+Other [Tailscale repos](https://github.com/orgs/tailscale/repositories) of note:
+
+* the Android app is at https://github.com/tailscale/tailscale-android
+* the Synology package is at https://github.com/tailscale/tailscale-synology
+* the QNAP package is at https://github.com/tailscale/tailscale-qpkg
+* the Chocolatey packaging is at https://github.com/tailscale/tailscale-chocolatey
+
+For background on which parts of Tailscale are open source and why,
+see [https://tailscale.com/opensource/](https://tailscale.com/opensource/).
 
 ## Using
 
-We serve packages for a variety of distros at
-https://pkgs.tailscale.com .
+We serve packages for a variety of distros and platforms at
+[https://pkgs.tailscale.com](https://pkgs.tailscale.com/).
 
 ## Other clients
 
 The [macOS, iOS, and Windows clients](https://tailscale.com/download)
 use the code in this repository but additionally include small GUI
-wrappers that are not open source.
+wrappers. The GUI wrappers on non-open source platforms are themselves
+not open source.
 
 ## Building
 
+We always require the latest Go release, currently Go 1.20. (While we build
+releases with our [Go fork](https://github.com/tailscale/go/), its use is not
+required.)
+
 ```
 go install tailscale.com/cmd/tailscale{,d}
 ```
@@ -42,11 +57,6 @@ If your distro has conventions that preclude the use of
 `build_dist.sh`, please do the equivalent of what it does in your
 distro's way, so that bug reports contain useful version information.
 
-We only guarantee to support the latest Go release and any Go beta or
-release candidate builds (currently Go 1.16) in module mode. It might
-work in earlier Go versions or in GOPATH mode, but we're making no
-effort to keep those working.
-
 ## Bugs
 
 Please file any issues about this code or the hosted service on
@@ -61,6 +71,9 @@ We require [Developer Certificate of
 Origin](https://en.wikipedia.org/wiki/Developer_Certificate_of_Origin)
 `Signed-off-by` lines in commits.
 
+See `git log` for our commit message style. It's basically the same as
+[Go's style](https://github.com/golang/go/wiki/CommitMessage).
+
 ## About Us
 
 [Tailscale](https://tailscale.com/) is primarily developed by the

VERSION.txt

@@ -1 +1 @@
-1.13.0
+1.46.1

atomicfile/atomicfile.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2019 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // Package atomicfile contains code related to writing to filesystems
 // atomically.
@@ -9,16 +8,21 @@
 package atomicfile // import "tailscale.com/atomicfile"
 
 import (
-	"io/ioutil"
+	"fmt"
 	"os"
 	"path/filepath"
 	"runtime"
 )
 
-// WriteFile writes data to filename+some suffix, then renames it
-// into filename.
+// WriteFile writes data to filename+some suffix, then renames it into filename.
+// The perm argument is ignored on Windows. If the target filename already
+// exists but is not a regular file, WriteFile returns an error.
 func WriteFile(filename string, data []byte, perm os.FileMode) (err error) {
-	f, err := ioutil.TempFile(filepath.Dir(filename), filepath.Base(filename)+".tmp")
+	fi, err := os.Stat(filename)
+	if err == nil && !fi.Mode().IsRegular() {
+		return fmt.Errorf("%s already exists and is not a regular file", filename)
+	}
+	f, err := os.CreateTemp(filepath.Dir(filename), filepath.Base(filename)+".tmp")
 	if err != nil {
 		return err
 	}

atomicfile/atomicfile_test.go

@@ -0,0 +1,47 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build !js && !windows
+
+package atomicfile
+
+import (
+	"net"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestDoesNotOverwriteIrregularFiles(t *testing.T) {
+	// Per tailscale/tailscale#7658 as one example, almost any imagined use of
+	// atomicfile.Write should likely not attempt to overwrite an irregular file
+	// such as a device node, socket, or named pipe.
+
+	const filename = "TestDoesNotOverwriteIrregularFiles"
+	var path string
+	// macOS private temp does not allow unix socket creation, but /tmp does.
+	if runtime.GOOS == "darwin" {
+		path = filepath.Join("/tmp", filename)
+		t.Cleanup(func() { os.Remove(path) })
+	} else {
+		path = filepath.Join(t.TempDir(), filename)
+	}
+
+	// The least troublesome thing to make that is not a file is a unix socket.
+	// Making a null device sadly requires root.
+	l, err := net.ListenUnix("unix", &net.UnixAddr{Name: path, Net: "unix"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer l.Close()
+
+	err = WriteFile(path, []byte("hello"), 0644)
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	if !strings.Contains(err.Error(), "is not a regular file") {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}

build_dist.sh

@@ -11,36 +11,42 @@
 
 set -eu
 
-IFS=".$IFS" read -r major minor patch <VERSION.txt
-git_hash=$(git rev-parse HEAD)
-if ! git diff-index --quiet HEAD; then
-	git_hash="${git_hash}-dirty"
-fi
-base_hash=$(git rev-list --max-count=1 HEAD -- VERSION.txt)
-change_count=$(git rev-list --count HEAD "^$base_hash")
-short_hash=$(echo "$git_hash" | cut -c1-9)
-
-if expr "$minor" : "[0-9]*[13579]$" >/dev/null; then
-	patch="$change_count"
-	change_suffix=""
-elif [ "$change_count" != "0" ]; then
-	change_suffix="-$change_count"
-else
-	change_suffix=""
+go="go"
+if [ -n "${TS_USE_TOOLCHAIN:-}" ]; then
+	go="./tool/go"
 fi
 
-long_suffix="$change_suffix-t$short_hash"
-SHORT="$major.$minor.$patch"
-LONG="${SHORT}$long_suffix"
-GIT_HASH="$git_hash"
+eval `CGO_ENABLED=0 GOOS=$($go env GOHOSTOS) GOARCH=$($go env GOHOSTARCH) $go run ./cmd/mkversion`
 
 if [ "$1" = "shellvars" ]; then
 	cat <<EOF
-VERSION_SHORT="$SHORT"
-VERSION_LONG="$LONG"
-VERSION_GIT_HASH="$GIT_HASH"
+VERSION_MINOR="$VERSION_MINOR"
+VERSION_SHORT="$VERSION_SHORT"
+VERSION_LONG="$VERSION_LONG"
+VERSION_GIT_HASH="$VERSION_GIT_HASH"
 EOF
 	exit 0
 fi
 
-exec go build -ldflags "-X tailscale.com/version.Long=${LONG} -X tailscale.com/version.Short=${SHORT} -X tailscale.com/version.GitCommit=${GIT_HASH}" "$@"
+tags=""
+ldflags="-X tailscale.com/version.longStamp=${VERSION_LONG} -X tailscale.com/version.shortStamp=${VERSION_SHORT}"
+
+# build_dist.sh arguments must precede go build arguments.
+while [ "$#" -gt 1 ]; do
+	case "$1" in
+	--extra-small)
+		shift
+		ldflags="$ldflags -w -s"
+		tags="${tags:+$tags,}ts_omit_aws,ts_omit_bird,ts_omit_tap,ts_omit_kube"
+		;;
+	--box)
+		shift
+		tags="${tags:+$tags,}ts_include_cli"
+		;;
+	*)
+		break
+		;;
+	esac
+done
+
+exec $go build ${tags:+-tags=$tags} -ldflags "$ldflags" "$@"

build_docker.sh

@@ -8,27 +8,67 @@
 #
 ############################################################################
 #
-# WARNING: Tailscale is not yet officially supported in Docker,
-# Kubernetes, etc.
+# WARNING: Tailscale is not yet officially supported in container
+# environments, such as Docker and Kubernetes. Though it should work, we
+# don't regularly test it, and we know there are some feature limitations.
 #
-# It might work, but we don't regularly test it, and it's not as polished as
-# our currently supported platforms. This is provided for people who know
-# how Tailscale works and what they're doing.
-#
-# Our tracking bug for officially support container use cases is:
-#    https://github.com/tailscale/tailscale/issues/504
-#
-# Also, see the various bugs tagged "containers":
+# See current bugs tagged "containers":
 #    https://github.com/tailscale/tailscale/labels/containers
 #
 ############################################################################
 
 set -eu
 
+# Use the "go" binary from the "tool" directory (which is github.com/tailscale/go)
+export PATH=$PWD/tool:$PATH
+
 eval $(./build_dist.sh shellvars)
 
-docker build \
-  --build-arg VERSION_LONG=$VERSION_LONG \
-  --build-arg VERSION_SHORT=$VERSION_SHORT \
-  --build-arg VERSION_GIT_HASH=$VERSION_GIT_HASH \
-  -t tailscale:tailscale .
+DEFAULT_TARGET="client"
+DEFAULT_TAGS="v${VERSION_SHORT},v${VERSION_MINOR}"
+DEFAULT_BASE="tailscale/alpine-base:3.16"
+
+PUSH="${PUSH:-false}"
+TARGET="${TARGET:-${DEFAULT_TARGET}}"
+TAGS="${TAGS:-${DEFAULT_TAGS}}"
+BASE="${BASE:-${DEFAULT_BASE}}"
+
+case "$TARGET" in
+  client)
+    DEFAULT_REPOS="tailscale/tailscale"
+    REPOS="${REPOS:-${DEFAULT_REPOS}}"
+    go run github.com/tailscale/mkctr \
+      --gopaths="\
+        tailscale.com/cmd/tailscale:/usr/local/bin/tailscale, \
+        tailscale.com/cmd/tailscaled:/usr/local/bin/tailscaled, \
+        tailscale.com/cmd/containerboot:/usr/local/bin/containerboot" \
+      --ldflags="\
+        -X tailscale.com/version.longStamp=${VERSION_LONG} \
+        -X tailscale.com/version.shortStamp=${VERSION_SHORT} \
+        -X tailscale.com/version.gitCommitStamp=${VERSION_GIT_HASH}" \
+      --base="${BASE}" \
+      --tags="${TAGS}" \
+      --repos="${REPOS}" \
+      --push="${PUSH}" \
+      /usr/local/bin/containerboot
+    ;;
+  operator)
+    DEFAULT_REPOS="tailscale/k8s-operator"
+    REPOS="${REPOS:-${DEFAULT_REPOS}}"
+    go run github.com/tailscale/mkctr \
+      --gopaths="tailscale.com/cmd/k8s-operator:/usr/local/bin/operator" \
+      --ldflags="\
+        -X tailscale.com/version.longStamp=${VERSION_LONG} \
+        -X tailscale.com/version.shortStamp=${VERSION_SHORT} \
+        -X tailscale.com/version.gitCommitStamp=${VERSION_GIT_HASH}" \
+      --base="${BASE}" \
+      --tags="${TAGS}" \
+      --repos="${REPOS}" \
+      --push="${PUSH}" \
+      /usr/local/bin/operator
+    ;;
+  *)
+    echo "unknown target: $TARGET"
+    exit 1
+    ;;
+esac

chirp/chirp.go

@@ -0,0 +1,163 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package chirp implements a client to communicate with the BIRD Internet
+// Routing Daemon.
+package chirp
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"strings"
+	"time"
+)
+
+const (
+	// Maximum amount of time we should wait when reading a response from BIRD.
+	responseTimeout = 10 * time.Second
+)
+
+// New creates a BIRDClient.
+func New(socket string) (*BIRDClient, error) {
+	return newWithTimeout(socket, responseTimeout)
+}
+
+func newWithTimeout(socket string, timeout time.Duration) (_ *BIRDClient, err error) {
+	conn, err := net.Dial("unix", socket)
+	if err != nil {
+		return nil, fmt.Errorf("failed to connect to BIRD: %w", err)
+	}
+	defer func() {
+		if err != nil {
+			conn.Close()
+		}
+	}()
+
+	b := &BIRDClient{
+		socket:  socket,
+		conn:    conn,
+		scanner: bufio.NewScanner(conn),
+		timeNow: time.Now,
+		timeout: timeout,
+	}
+	// Read and discard the first line as that is the welcome message.
+	if _, err := b.readResponse(); err != nil {
+		return nil, err
+	}
+	return b, nil
+}
+
+// BIRDClient handles communication with the BIRD Internet Routing Daemon.
+type BIRDClient struct {
+	socket  string
+	conn    net.Conn
+	scanner *bufio.Scanner
+	timeNow func() time.Time
+	timeout time.Duration
+}
+
+// Close closes the underlying connection to BIRD.
+func (b *BIRDClient) Close() error { return b.conn.Close() }
+
+// DisableProtocol disables the provided protocol.
+func (b *BIRDClient) DisableProtocol(protocol string) error {
+	out, err := b.exec("disable %s", protocol)
+	if err != nil {
+		return err
+	}
+	if strings.Contains(out, fmt.Sprintf("%s: already disabled", protocol)) {
+		return nil
+	} else if strings.Contains(out, fmt.Sprintf("%s: disabled", protocol)) {
+		return nil
+	}
+	return fmt.Errorf("failed to disable %s: %v", protocol, out)
+}
+
+// EnableProtocol enables the provided protocol.
+func (b *BIRDClient) EnableProtocol(protocol string) error {
+	out, err := b.exec("enable %s", protocol)
+	if err != nil {
+		return err
+	}
+	if strings.Contains(out, fmt.Sprintf("%s: already enabled", protocol)) {
+		return nil
+	} else if strings.Contains(out, fmt.Sprintf("%s: enabled", protocol)) {
+		return nil
+	}
+	return fmt.Errorf("failed to enable %s: %v", protocol, out)
+}
+
+// BIRD CLI docs from https://bird.network.cz/?get_doc&v=20&f=prog-2.html#ss2.9
+
+// Each session of the CLI consists of a sequence of request and replies,
+// slightly resembling the FTP and SMTP protocols.
+// Requests are commands encoded as a single line of text,
+// replies are sequences of lines starting with a four-digit code
+// followed by either a space (if it's the last line of the reply) or
+// a minus sign (when the reply is going to continue with the next line),
+// the rest of the line contains a textual message semantics of which depends on the numeric code.
+// If a reply line has the same code as the previous one and it's a continuation line,
+// the whole prefix can be replaced by a single white space character.
+//
+// Reply codes starting with 0 stand for ‘action successfully completed’ messages,
+// 1 means ‘table entry’, 8 ‘runtime error’ and 9 ‘syntax error’.
+
+func (b *BIRDClient) exec(cmd string, args ...any) (string, error) {
+	if err := b.conn.SetWriteDeadline(b.timeNow().Add(b.timeout)); err != nil {
+		return "", err
+	}
+	if _, err := fmt.Fprintf(b.conn, cmd, args...); err != nil {
+		return "", err
+	}
+	if _, err := fmt.Fprintln(b.conn); err != nil {
+		return "", err
+	}
+	return b.readResponse()
+}
+
+// hasResponseCode reports whether the provided byte slice is
+// prefixed with a BIRD response code.
+// Equivalent regex: `^\d{4}[ -]`.
+func hasResponseCode(s []byte) bool {
+	if len(s) < 5 {
+		return false
+	}
+	for _, b := range s[:4] {
+		if '0' <= b && b <= '9' {
+			continue
+		}
+		return false
+	}
+	return s[4] == ' ' || s[4] == '-'
+}
+
+func (b *BIRDClient) readResponse() (string, error) {
+	// Set the read timeout before we start reading anything.
+	if err := b.conn.SetReadDeadline(b.timeNow().Add(b.timeout)); err != nil {
+		return "", err
+	}
+
+	var resp strings.Builder
+	var done bool
+	for !done {
+		if !b.scanner.Scan() {
+			if err := b.scanner.Err(); err != nil {
+				return "", err
+			}
+
+			return "", fmt.Errorf("reading response from bird failed (EOF): %q", resp.String())
+		}
+		out := b.scanner.Bytes()
+		if _, err := resp.Write(out); err != nil {
+			return "", err
+		}
+		if hasResponseCode(out) {
+			done = out[4] == ' '
+		}
+		if !done {
+			resp.WriteRune('\n')
+		}
+	}
+	return resp.String(), nil
+}

chirp/chirp_test.go

@@ -0,0 +1,192 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+package chirp
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+)
+
+type fakeBIRD struct {
+	net.Listener
+	protocolsEnabled map[string]bool
+	sock             string
+}
+
+func newFakeBIRD(t *testing.T, protocols ...string) *fakeBIRD {
+	sock := filepath.Join(t.TempDir(), "sock")
+	l, err := net.Listen("unix", sock)
+	if err != nil {
+		t.Fatal(err)
+	}
+	pe := make(map[string]bool)
+	for _, p := range protocols {
+		pe[p] = false
+	}
+	return &fakeBIRD{
+		Listener:         l,
+		protocolsEnabled: pe,
+		sock:             sock,
+	}
+}
+
+func (fb *fakeBIRD) listen() error {
+	for {
+		c, err := fb.Accept()
+		if err != nil {
+			if errors.Is(err, net.ErrClosed) {
+				return nil
+			}
+			return err
+		}
+		go fb.handle(c)
+	}
+}
+
+func (fb *fakeBIRD) handle(c net.Conn) {
+	fmt.Fprintln(c, "0001 BIRD 2.0.8 ready.")
+	sc := bufio.NewScanner(c)
+	for sc.Scan() {
+		cmd := sc.Text()
+		args := strings.Split(cmd, " ")
+		switch args[0] {
+		case "enable":
+			en, ok := fb.protocolsEnabled[args[1]]
+			if !ok {
+				fmt.Fprintln(c, "9001 syntax error, unexpected CF_SYM_UNDEFINED, expecting CF_SYM_KNOWN or TEXT or ALL")
+			} else if en {
+				fmt.Fprintf(c, "0010-%s: already enabled\n", args[1])
+			} else {
+				fmt.Fprintf(c, "0011-%s: enabled\n", args[1])
+			}
+			fmt.Fprintln(c, "0000 ")
+			fb.protocolsEnabled[args[1]] = true
+		case "disable":
+			en, ok := fb.protocolsEnabled[args[1]]
+			if !ok {
+				fmt.Fprintln(c, "9001 syntax error, unexpected CF_SYM_UNDEFINED, expecting CF_SYM_KNOWN or TEXT or ALL")
+			} else if !en {
+				fmt.Fprintf(c, "0008-%s: already disabled\n", args[1])
+			} else {
+				fmt.Fprintf(c, "0009-%s: disabled\n", args[1])
+			}
+			fmt.Fprintln(c, "0000 ")
+			fb.protocolsEnabled[args[1]] = false
+		}
+	}
+}
+
+func TestChirp(t *testing.T) {
+	fb := newFakeBIRD(t, "tailscale")
+	defer fb.Close()
+	go fb.listen()
+	c, err := New(fb.sock)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := c.EnableProtocol("tailscale"); err != nil {
+		t.Fatal(err)
+	}
+	if err := c.EnableProtocol("tailscale"); err != nil {
+		t.Fatal(err)
+	}
+	if err := c.DisableProtocol("tailscale"); err != nil {
+		t.Fatal(err)
+	}
+	if err := c.DisableProtocol("tailscale"); err != nil {
+		t.Fatal(err)
+	}
+	if err := c.EnableProtocol("rando"); err == nil {
+		t.Fatalf("enabling %q succeeded", "rando")
+	}
+	if err := c.DisableProtocol("rando"); err == nil {
+		t.Fatalf("disabling %q succeeded", "rando")
+	}
+}
+
+type hangingListener struct {
+	net.Listener
+	t    *testing.T
+	done chan struct{}
+	wg   sync.WaitGroup
+	sock string
+}
+
+func newHangingListener(t *testing.T) *hangingListener {
+	sock := filepath.Join(t.TempDir(), "sock")
+	l, err := net.Listen("unix", sock)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return &hangingListener{
+		Listener: l,
+		t:        t,
+		done:     make(chan struct{}),
+		sock:     sock,
+	}
+}
+
+func (hl *hangingListener) Stop() {
+	hl.Close()
+	close(hl.done)
+	hl.wg.Wait()
+}
+
+func (hl *hangingListener) listen() error {
+	for {
+		c, err := hl.Accept()
+		if err != nil {
+			if errors.Is(err, net.ErrClosed) {
+				return nil
+			}
+			return err
+		}
+		hl.wg.Add(1)
+		go hl.handle(c)
+	}
+}
+
+func (hl *hangingListener) handle(c net.Conn) {
+	defer hl.wg.Done()
+
+	// Write our fake first line of response so that we get into the read loop
+	fmt.Fprintln(c, "0001 BIRD 2.0.8 ready.")
+
+	ticker := time.NewTicker(2 * time.Second)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ticker.C:
+			hl.t.Logf("connection still hanging")
+		case <-hl.done:
+			return
+		}
+	}
+}
+
+func TestChirpTimeout(t *testing.T) {
+	fb := newHangingListener(t)
+	defer fb.Stop()
+	go fb.listen()
+
+	c, err := newWithTimeout(fb.sock, 500*time.Millisecond)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = c.EnableProtocol("tailscale")
+	if err == nil {
+		t.Fatal("got err=nil, want timeout")
+	}
+	if !os.IsTimeout(err) {
+		t.Fatalf("got err=%v, want os.IsTimeout(err)=true", err)
+	}
+}

client/tailscale/acl.go

@@ -0,0 +1,476 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/netip"
+)
+
+// ACLRow defines a rule that grants access by a set of users or groups to a set
+// of servers and ports.
+// Only one of Src/Dst or Users/Ports may be specified.
+type ACLRow struct {
+	Action string   `json:"action,omitempty"` // valid values: "accept"
+	Users  []string `json:"users,omitempty"`  // old name for src
+	Ports  []string `json:"ports,omitempty"`  // old name for dst
+	Src    []string `json:"src,omitempty"`
+	Dst    []string `json:"dst,omitempty"`
+}
+
+// ACLTest defines a test for your ACLs to prevent accidental exposure or
+// revoking of access to key servers and ports. Only one of Src or User may be
+// specified, and only one of Allow/Accept may be specified.
+type ACLTest struct {
+	Src    string   `json:"src,omitempty"`    // source
+	User   string   `json:"user,omitempty"`   // old name for source
+	Accept []string `json:"accept,omitempty"` // expected destination ip:port that user can access
+	Deny   []string `json:"deny,omitempty"`   // expected destination ip:port that user cannot access
+
+	Allow []string `json:"allow,omitempty"` // old name for accept
+}
+
+// ACLDetails contains all the details for an ACL.
+type ACLDetails struct {
+	Tests     []ACLTest           `json:"tests,omitempty"`
+	ACLs      []ACLRow            `json:"acls,omitempty"`
+	Groups    map[string][]string `json:"groups,omitempty"`
+	TagOwners map[string][]string `json:"tagowners,omitempty"`
+	Hosts     map[string]string   `json:"hosts,omitempty"`
+}
+
+// ACL contains an ACLDetails and metadata.
+type ACL struct {
+	ACL  ACLDetails
+	ETag string // to check with version on server
+}
+
+// ACLHuJSON contains the HuJSON string of the ACL and metadata.
+type ACLHuJSON struct {
+	ACL      string
+	Warnings []string
+	ETag     string // to check with version on server
+}
+
+// ACL makes a call to the Tailscale server to get a JSON-parsed version of the ACL.
+// The JSON-parsed version of the ACL contains no comments as proper JSON does not support
+// comments.
+func (c *Client) ACL(ctx context.Context) (acl *ACL, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.ACL: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Accept", "application/json")
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	// Otherwise, try to decode the response.
+	var aclDetails ACLDetails
+	if err = json.Unmarshal(b, &aclDetails); err != nil {
+		return nil, err
+	}
+	acl = &ACL{
+		ACL:  aclDetails,
+		ETag: resp.Header.Get("ETag"),
+	}
+	return acl, nil
+}
+
+// ACLHuJSON makes a call to the Tailscale server to get the ACL HuJSON and returns
+// it as a string.
+// HuJSON is JSON with a few modifications to make it more human-friendly. The primary
+// changes are allowing comments and trailing comments. See the following links for more info:
+// https://tailscale.com/s/acl-format
+// https://github.com/tailscale/hujson
+func (c *Client) ACLHuJSON(ctx context.Context) (acl *ACLHuJSON, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.ACLHuJSON: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl?details=1", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Accept", "application/hujson")
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	data := struct {
+		ACL      []byte   `json:"acl"`
+		Warnings []string `json:"warnings"`
+	}{}
+	if err := json.Unmarshal(b, &data); err != nil {
+		return nil, err
+	}
+
+	acl = &ACLHuJSON{
+		ACL:      string(data.ACL),
+		Warnings: data.Warnings,
+		ETag:     resp.Header.Get("ETag"),
+	}
+	return acl, nil
+}
+
+// ACLTestFailureSummary specifies a user for which ACL tests
+// failed and the related user-friendly error messages.
+//
+// ACLTestFailureSummary specifies the JSON format sent to the
+// JavaScript client to be rendered in the HTML.
+type ACLTestFailureSummary struct {
+	User     string   `json:"user,omitempty"`
+	Errors   []string `json:"errors,omitempty"`
+	Warnings []string `json:"warnings,omitempty"`
+}
+
+// ACLTestError is ErrResponse but with an extra field to account for ACLTestFailureSummary.
+type ACLTestError struct {
+	ErrResponse
+	Data []ACLTestFailureSummary `json:"data"`
+}
+
+func (e ACLTestError) Error() string {
+	return fmt.Sprintf("%s, Data: %+v", e.ErrResponse.Error(), e.Data)
+}
+
+func (c *Client) aclPOSTRequest(ctx context.Context, body []byte, avoidCollisions bool, etag, acceptHeader string) ([]byte, string, error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(body))
+	if err != nil {
+		return nil, "", err
+	}
+
+	if avoidCollisions {
+		req.Header.Set("If-Match", etag)
+	}
+	req.Header.Set("Accept", acceptHeader)
+	req.Header.Set("Content-Type", "application/hujson")
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, "", err
+	}
+
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		// check if test error
+		var ate ACLTestError
+		if err := json.Unmarshal(b, &ate); err != nil {
+			return nil, "", err
+		}
+		ate.Status = resp.StatusCode
+		return nil, "", ate
+	}
+	return b, resp.Header.Get("ETag"), nil
+}
+
+// SetACL sends a POST request to update the ACL according to the provided ACL object. If
+// `avoidCollisions` is true, it will use the ETag obtained in the GET request in an If-Match
+// header to check if the previously obtained ACL was the latest version and that no updates
+// were missed.
+//
+// Returns error with status code 412 if mistmached ETag and avoidCollisions is set to true.
+// Returns error if ACL has tests that fail.
+// Returns error if there are other errors with the ACL.
+func (c *Client) SetACL(ctx context.Context, acl ACL, avoidCollisions bool) (res *ACL, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetACL: %w", err)
+		}
+	}()
+	postData, err := json.Marshal(acl.ACL)
+	if err != nil {
+		return nil, err
+	}
+	b, etag, err := c.aclPOSTRequest(ctx, postData, avoidCollisions, acl.ETag, "application/json")
+	if err != nil {
+		return nil, err
+	}
+
+	// Otherwise, try to decode the response.
+	var aclDetails ACLDetails
+	if err = json.Unmarshal(b, &aclDetails); err != nil {
+		return nil, err
+	}
+	res = &ACL{
+		ACL:  aclDetails,
+		ETag: etag,
+	}
+	return res, nil
+}
+
+// SetACLHuJSON sends a POST request to update the ACL according to the provided ACL object. If
+// `avoidCollisions` is true, it will use the ETag obtained in the GET request in an If-Match
+// header to check if the previously obtained ACL was the latest version and that no updates
+// were missed.
+//
+// Returns error with status code 412 if mistmached ETag and avoidCollisions is set to true.
+// Returns error if the HuJSON is invalid.
+// Returns error if ACL has tests that fail.
+// Returns error if there are other errors with the ACL.
+func (c *Client) SetACLHuJSON(ctx context.Context, acl ACLHuJSON, avoidCollisions bool) (res *ACLHuJSON, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetACLHuJSON: %w", err)
+		}
+	}()
+
+	postData := []byte(acl.ACL)
+	b, etag, err := c.aclPOSTRequest(ctx, postData, avoidCollisions, acl.ETag, "application/hujson")
+	if err != nil {
+		return nil, err
+	}
+
+	res = &ACLHuJSON{
+		ACL:  string(b),
+		ETag: etag,
+	}
+	return res, nil
+}
+
+// UserRuleMatch specifies the source users/groups/hosts that a rule targets
+// and the destination ports that they can access.
+// LineNumber is only useful for requests provided in HuJSON form.
+// While JSON requests will have LineNumber, the value is not useful.
+type UserRuleMatch struct {
+	Users      []string `json:"users"`
+	Ports      []string `json:"ports"`
+	LineNumber int      `json:"lineNumber"`
+}
+
+// ACLPreviewResponse is the response type of previewACLPostRequest
+type ACLPreviewResponse struct {
+	Matches    []UserRuleMatch `json:"matches"`    // ACL rules that match the specified user or ipport.
+	Type       string          `json:"type"`       // The request type: currently only "user" or "ipport".
+	PreviewFor string          `json:"previewFor"` // A specific user or ipport.
+}
+
+// ACLPreview is the response type of PreviewACLForUser, PreviewACLForIPPort, PreviewACLHuJSONForUser, and PreviewACLHuJSONForIPPort
+type ACLPreview struct {
+	Matches []UserRuleMatch `json:"matches"`
+	User    string          `json:"user,omitempty"`   // Filled if response of PreviewACLForUser or PreviewACLHuJSONForUser
+	IPPort  string          `json:"ipport,omitempty"` // Filled if response of PreviewACLForIPPort or PreviewACLHuJSONForIPPort
+}
+
+func (c *Client) previewACLPostRequest(ctx context.Context, body []byte, previewType string, previewFor string) (res *ACLPreviewResponse, err error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl/preview", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(body))
+	if err != nil {
+		return nil, err
+	}
+
+	q := req.URL.Query()
+	q.Add("type", previewType)
+	q.Add("previewFor", previewFor)
+	req.URL.RawQuery = q.Encode()
+
+	req.Header.Set("Content-Type", "application/hujson")
+	c.setAuth(req)
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+	if err = json.Unmarshal(b, &res); err != nil {
+		return nil, err
+	}
+
+	return res, nil
+}
+
+// PreviewACLForUser determines what rules match a given ACL for a user.
+// The ACL can be a locally modified or clean ACL obtained from server.
+//
+// Returns ACLPreview on success with matches in a slice. If there are no matches,
+// the call is still successful but Matches will be an empty slice.
+// Returns error if the provided ACL is invalid.
+func (c *Client) PreviewACLForUser(ctx context.Context, acl ACL, user string) (res *ACLPreview, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.PreviewACLForUser: %w", err)
+		}
+	}()
+	postData, err := json.Marshal(acl.ACL)
+	if err != nil {
+		return nil, err
+	}
+	b, err := c.previewACLPostRequest(ctx, postData, "user", user)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ACLPreview{
+		Matches: b.Matches,
+		User:    b.PreviewFor,
+	}, nil
+}
+
+// PreviewACLForIPPort determines what rules match a given ACL for a ipport.
+// The ACL can be a locally modified or clean ACL obtained from server.
+//
+// Returns ACLPreview on success with matches in a slice. If there are no matches,
+// the call is still successful but Matches will be an empty slice.
+// Returns error if the provided ACL is invalid.
+func (c *Client) PreviewACLForIPPort(ctx context.Context, acl ACL, ipport netip.AddrPort) (res *ACLPreview, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.PreviewACLForIPPort: %w", err)
+		}
+	}()
+	postData, err := json.Marshal(acl.ACL)
+	if err != nil {
+		return nil, err
+	}
+	b, err := c.previewACLPostRequest(ctx, postData, "ipport", ipport.String())
+	if err != nil {
+		return nil, err
+	}
+
+	return &ACLPreview{
+		Matches: b.Matches,
+		IPPort:  b.PreviewFor,
+	}, nil
+}
+
+// PreviewACLHuJSONForUser determines what rules match a given ACL for a user.
+// The ACL can be a locally modified or clean ACL obtained from server.
+//
+// Returns ACLPreview on success with matches in a slice. If there are no matches,
+// the call is still successful but Matches will be an empty slice.
+// Returns error if the provided ACL is invalid.
+func (c *Client) PreviewACLHuJSONForUser(ctx context.Context, acl ACLHuJSON, user string) (res *ACLPreview, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.PreviewACLHuJSONForUser: %w", err)
+		}
+	}()
+	postData := []byte(acl.ACL)
+	b, err := c.previewACLPostRequest(ctx, postData, "user", user)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ACLPreview{
+		Matches: b.Matches,
+		User:    b.PreviewFor,
+	}, nil
+}
+
+// PreviewACLHuJSONForIPPort determines what rules match a given ACL for a ipport.
+// The ACL can be a locally modified or clean ACL obtained from server.
+//
+// Returns ACLPreview on success with matches in a slice. If there are no matches,
+// the call is still successful but Matches will be an empty slice.
+// Returns error if the provided ACL is invalid.
+func (c *Client) PreviewACLHuJSONForIPPort(ctx context.Context, acl ACLHuJSON, ipport string) (res *ACLPreview, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.PreviewACLHuJSONForIPPort: %w", err)
+		}
+	}()
+	postData := []byte(acl.ACL)
+	b, err := c.previewACLPostRequest(ctx, postData, "ipport", ipport)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ACLPreview{
+		Matches: b.Matches,
+		IPPort:  b.PreviewFor,
+	}, nil
+}
+
+// ValidateACLJSON takes in the given source and destination (in this situation,
+// it is assumed that you are checking whether the source can connect to destination)
+// and creates an ACLTest from that. It then sends the ACLTest to the control api acl
+// validate endpoint, where the test is run. It returns a nil ACLTestError pointer if
+// no test errors occur.
+func (c *Client) ValidateACLJSON(ctx context.Context, source, dest string) (testErr *ACLTestError, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.ValidateACLJSON: %w", err)
+		}
+	}()
+
+	tests := []ACLTest{{User: source, Allow: []string{dest}}}
+	postData, err := json.Marshal(tests)
+	if err != nil {
+		return nil, err
+	}
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/acl/validate", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(postData))
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	c.setAuth(req)
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("control api responded with %d status code", resp.StatusCode)
+	}
+
+	// The test ran without fail
+	if len(b) == 0 {
+		return nil, nil
+	}
+
+	var res ACLTestError
+	// The test returned errors.
+	if err = json.Unmarshal(b, &res); err != nil {
+		// failed to unmarshal
+		return nil, err
+	}
+	return &res, nil
+}

client/tailscale/apitype/apitype.go

@@ -1,16 +1,21 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
-// Package apitype contains types for the Tailscale local API.
+// Package apitype contains types for the Tailscale LocalAPI and control plane API.
 package apitype
 
 import "tailscale.com/tailcfg"
 
+// LocalAPIHost is the Host header value used by the LocalAPI.
+const LocalAPIHost = "local-tailscaled.sock"
+
 // WhoIsResponse is the JSON type returned by tailscaled debug server's /whois?ip=$IP handler.
 type WhoIsResponse struct {
 	Node        *tailcfg.Node
 	UserProfile *tailcfg.UserProfile
+
+	// Caps are extra capabilities that the remote Node has to this node.
+	Caps []string `json:",omitempty"`
 }
 
 // FileTarget is a node to which files can be sent, and the PeerAPI
@@ -18,7 +23,7 @@ type WhoIsResponse struct {
 type FileTarget struct {
 	Node *tailcfg.Node
 
-	// PeerAPI is the http://ip:port URL base of the node's peer API,
+	// PeerAPI is the http://ip:port URL base of the node's PeerAPI,
 	// without any path (not even a single slash).
 	PeerAPIURL string
 }
@@ -27,3 +32,9 @@ type WaitingFile struct {
 	Name string
 	Size int64
 }
+
+// SetPushDeviceTokenRequest is the body POSTed to the LocalAPI endpoint /set-device-token.
+type SetPushDeviceTokenRequest struct {
+	// PushDeviceToken is the iOS/macOS APNs device token (and any future Android equivalent).
+	PushDeviceToken string
+}

client/tailscale/apitype/controltype.go

@@ -0,0 +1,18 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package apitype
+
+type DNSConfig struct {
+	Resolvers         []DNSResolver            `json:"resolvers"`
+	FallbackResolvers []DNSResolver            `json:"fallbackResolvers"`
+	Routes            map[string][]DNSResolver `json:"routes"`
+	Domains           []string                 `json:"domains"`
+	Nameservers       []string                 `json:"nameservers"`
+	Proxied           bool                     `json:"proxied"`
+}
+
+type DNSResolver struct {
+	Addr                string   `json:"addr"`
+	BootstrapResolution []string `json:"bootstrapResolution,omitempty"`
+}

client/tailscale/devices.go

@@ -0,0 +1,272 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"tailscale.com/types/opt"
+)
+
+type GetDevicesResponse struct {
+	Devices []*Device `json:"devices"`
+}
+
+type DerpRegion struct {
+	Preferred           bool    `json:"preferred,omitempty"`
+	LatencyMilliseconds float64 `json:"latencyMs"`
+}
+
+type ClientConnectivity struct {
+	Endpoints             []string `json:"endpoints"`
+	DERP                  string   `json:"derp"`
+	MappingVariesByDestIP opt.Bool `json:"mappingVariesByDestIP"`
+	// DERPLatency is mapped by region name (e.g. "New York City", "Seattle").
+	DERPLatency    map[string]DerpRegion `json:"latency"`
+	ClientSupports map[string]opt.Bool   `json:"clientSupports"`
+}
+
+type Device struct {
+	// Addresses is a list of the devices's Tailscale IP addresses.
+	// It's currently just 1 element, the 100.x.y.z Tailscale IP.
+	Addresses []string `json:"addresses"`
+	DeviceID  string   `json:"id"`
+	User      string   `json:"user"`
+	Name      string   `json:"name"`
+	Hostname  string   `json:"hostname"`
+
+	ClientVersion     string   `json:"clientVersion"`   // Empty for external devices.
+	UpdateAvailable   bool     `json:"updateAvailable"` // Empty for external devices.
+	OS                string   `json:"os"`
+	Tags              []string `json:"tags"`
+	Created           string   `json:"created"` // Empty for external devices.
+	LastSeen          string   `json:"lastSeen"`
+	KeyExpiryDisabled bool     `json:"keyExpiryDisabled"`
+	Expires           string   `json:"expires"`
+	Authorized        bool     `json:"authorized"`
+	IsExternal        bool     `json:"isExternal"`
+	MachineKey        string   `json:"machineKey"` // Empty for external devices.
+	NodeKey           string   `json:"nodeKey"`
+
+	// BlocksIncomingConnections is configured via the device's
+	// Tailscale client preferences. This field is only reported
+	// to the API starting with Tailscale 1.3.x clients.
+	BlocksIncomingConnections bool `json:"blocksIncomingConnections"`
+
+	// The following fields are not included by default:
+
+	// EnabledRoutes are the previously-approved subnet routes
+	// (e.g. "192.168.4.16/24", "10.5.2.4/32").
+	EnabledRoutes []string `json:"enabledRoutes"` // Empty for external devices.
+	// AdvertisedRoutes are the subnets (both enabled and not enabled)
+	// being requested from the node.
+	AdvertisedRoutes []string `json:"advertisedRoutes"` // Empty for external devices.
+
+	ClientConnectivity *ClientConnectivity `json:"clientConnectivity"`
+}
+
+// DeviceFieldsOpts determines which fields should be returned in the response.
+//
+// Please only use DeviceAllFields and DeviceDefaultFields.
+// Other DeviceFieldsOpts are not supported.
+//
+// TODO: Support other DeviceFieldsOpts.
+// In the future, users should be able to create their own DeviceFieldsOpts
+// as valid arguments by setting the fields they want returned to a "non-nil"
+// value. For example, DeviceFieldsOpts{NodeID: "true"} should only return NodeIDs.
+type DeviceFieldsOpts Device
+
+func (d *DeviceFieldsOpts) addFieldsToQueryParameter() string {
+	if d == DeviceDefaultFields || d == nil {
+		return "default"
+	}
+	if d == DeviceAllFields {
+		return "all"
+	}
+
+	return ""
+}
+
+var (
+	DeviceAllFields = &DeviceFieldsOpts{}
+
+	// DeviceDefaultFields specifies that the following fields are returned:
+	//   Addresses, NodeID, User, Name, Hostname, ClientVersion, UpdateAvailable,
+	//   OS, Created, LastSeen, KeyExpiryDisabled, Expires, Authorized, IsExternal
+	//   MachineKey, NodeKey, BlocksIncomingConnections.
+	DeviceDefaultFields = &DeviceFieldsOpts{}
+)
+
+// Devices retrieves the list of devices for a tailnet.
+//
+// See the Device structure for the list of fields hidden for external devices.
+// The optional fields parameter specifies which fields of the devices to return; currently
+// only DeviceDefaultFields (equivalent to nil) and DeviceAllFields are supported.
+// Other values are currently undefined.
+func (c *Client) Devices(ctx context.Context, fields *DeviceFieldsOpts) (deviceList []*Device, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.Devices: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/devices", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+	// Add fields.
+	fieldStr := fields.addFieldsToQueryParameter()
+	q := req.URL.Query()
+	q.Add("fields", fieldStr)
+	req.URL.RawQuery = q.Encode()
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	var devices GetDevicesResponse
+	err = json.Unmarshal(b, &devices)
+	return devices.Devices, err
+}
+
+// Device retrieved the details for a specific device.
+//
+// See the Device structure for the list of fields hidden for an external device.
+// The optional fields parameter specifies which fields of the devices to return; currently
+// only DeviceDefaultFields (equivalent to nil) and DeviceAllFields are supported.
+// Other values are currently undefined.
+func (c *Client) Device(ctx context.Context, deviceID string, fields *DeviceFieldsOpts) (device *Device, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.Device: %w", err)
+		}
+	}()
+	path := fmt.Sprintf("%s/api/v2/device/%s", c.baseURL(), deviceID)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	// Add fields.
+	fieldStr := fields.addFieldsToQueryParameter()
+	q := req.URL.Query()
+	q.Add("fields", fieldStr)
+	req.URL.RawQuery = q.Encode()
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	err = json.Unmarshal(b, &device)
+	return device, err
+}
+
+// DeleteDevice deletes the specified device from the Client's tailnet.
+// NOTE: Only devices that belong to the Client's tailnet can be deleted.
+// Deleting external devices is not supported.
+func (c *Client) DeleteDevice(ctx context.Context, deviceID string) (err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.DeleteDevice: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/device/%s", c.baseURL(), url.PathEscape(deviceID))
+	req, err := http.NewRequestWithContext(ctx, "DELETE", path, nil)
+	if err != nil {
+		return err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return handleErrorResponse(b, resp)
+	}
+	return nil
+}
+
+// AuthorizeDevice marks a device as authorized.
+func (c *Client) AuthorizeDevice(ctx context.Context, deviceID string) error {
+	return c.SetAuthorized(ctx, deviceID, true)
+}
+
+// SetAuthorized marks a device as authorized or not.
+func (c *Client) SetAuthorized(ctx context.Context, deviceID string, authorized bool) error {
+	params := &struct {
+		Authorized bool `json:"authorized"`
+	}{Authorized: authorized}
+	data, err := json.Marshal(params)
+	if err != nil {
+		return err
+	}
+	path := fmt.Sprintf("%s/api/v2/device/%s/authorized", c.baseURL(), url.PathEscape(deviceID))
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(data))
+	if err != nil {
+		return err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return handleErrorResponse(b, resp)
+	}
+
+	return nil
+}
+
+// SetTags updates the ACL tags on a device.
+func (c *Client) SetTags(ctx context.Context, deviceID string, tags []string) error {
+	params := &struct {
+		Tags []string `json:"tags"`
+	}{Tags: tags}
+	data, err := json.Marshal(params)
+	if err != nil {
+		return err
+	}
+	path := fmt.Sprintf("%s/api/v2/device/%s/tags", c.baseURL(), url.PathEscape(deviceID))
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(data))
+	if err != nil {
+		return err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return handleErrorResponse(b, resp)
+	}
+
+	return nil
+}

client/tailscale/dns.go

@@ -0,0 +1,233 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"tailscale.com/client/tailscale/apitype"
+)
+
+// DNSNameServers is returned when retrieving the list of nameservers.
+// It is also the structure provided when setting nameservers.
+type DNSNameServers struct {
+	DNS []string `json:"dns"` // DNS name servers
+}
+
+// DNSNameServersPostResponse is returned when setting the list of DNS nameservers.
+//
+// It includes the MagicDNS status since nameservers changes may affect MagicDNS.
+type DNSNameServersPostResponse struct {
+	DNS      []string `json:"dns"`      // DNS name servers
+	MagicDNS bool     `json:"magicDNS"` // whether MagicDNS is active for this tailnet (enabled + has fallback nameservers)
+}
+
+// DNSSearchpaths is the list of search paths for a given domain.
+type DNSSearchPaths struct {
+	SearchPaths []string `json:"searchPaths"` // DNS search paths
+}
+
+// DNSPreferences is the preferences set for a given tailnet.
+//
+// It includes MagicDNS which can be turned on or off. To enable MagicDNS,
+// there must be at least one nameserver. When all nameservers are removed,
+// MagicDNS is disabled.
+type DNSPreferences struct {
+	MagicDNS bool `json:"magicDNS"` // whether MagicDNS is active for this tailnet (enabled + has fallback nameservers)
+}
+
+func (c *Client) dnsGETRequest(ctx context.Context, endpoint string) ([]byte, error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/dns/%s", c.baseURL(), c.tailnet, endpoint)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	return b, nil
+}
+
+func (c *Client) dnsPOSTRequest(ctx context.Context, endpoint string, postData any) ([]byte, error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/dns/%s", c.baseURL(), c.tailnet, endpoint)
+	data, err := json.Marshal(&postData)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(data))
+	req.Header.Set("Content-Type", "application/json")
+	if err != nil {
+		return nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	return b, nil
+}
+
+// DNSConfig retrieves the DNSConfig settings for a domain.
+func (c *Client) DNSConfig(ctx context.Context) (cfg *apitype.DNSConfig, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.DNSConfig: %w", err)
+		}
+	}()
+	b, err := c.dnsGETRequest(ctx, "config")
+	if err != nil {
+		return nil, err
+	}
+	var dnsResp apitype.DNSConfig
+	err = json.Unmarshal(b, &dnsResp)
+	return &dnsResp, err
+}
+
+func (c *Client) SetDNSConfig(ctx context.Context, cfg apitype.DNSConfig) (resp *apitype.DNSConfig, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetDNSConfig: %w", err)
+		}
+	}()
+	var dnsResp apitype.DNSConfig
+	b, err := c.dnsPOSTRequest(ctx, "config", cfg)
+	if err != nil {
+		return nil, err
+	}
+	err = json.Unmarshal(b, &dnsResp)
+	return &dnsResp, err
+}
+
+// NameServers retrieves the list of nameservers set for a domain.
+func (c *Client) NameServers(ctx context.Context) (nameservers []string, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.NameServers: %w", err)
+		}
+	}()
+	b, err := c.dnsGETRequest(ctx, "nameservers")
+	if err != nil {
+		return nil, err
+	}
+	var dnsResp DNSNameServers
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp.DNS, err
+}
+
+// SetNameServers sets the list of nameservers for a tailnet to the list provided
+// by the user.
+//
+// It returns the new list of nameservers and the MagicDNS status in case it was
+// affected by the change. For example, removing all nameservers will turn off
+// MagicDNS.
+func (c *Client) SetNameServers(ctx context.Context, nameservers []string) (dnsResp *DNSNameServersPostResponse, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetNameServers: %w", err)
+		}
+	}()
+	dnsReq := DNSNameServers{DNS: nameservers}
+	b, err := c.dnsPOSTRequest(ctx, "nameservers", dnsReq)
+	if err != nil {
+		return nil, err
+	}
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp, err
+}
+
+// DNSPreferences retrieves the DNS preferences set for a tailnet.
+//
+// It returns the status of MagicDNS.
+func (c *Client) DNSPreferences(ctx context.Context) (dnsResp *DNSPreferences, err error) {
+	// Format return errors to be descriptive.
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.DNSPreferences: %w", err)
+		}
+	}()
+	b, err := c.dnsGETRequest(ctx, "preferences")
+	if err != nil {
+		return nil, err
+	}
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp, err
+}
+
+// SetDNSPreferences sets the DNS preferences for a tailnet.
+//
+// MagicDNS can only be enabled when there is at least one nameserver provided.
+// When all nameservers are removed, MagicDNS is disabled and will stay disabled,
+// unless explicitly enabled by a user again.
+func (c *Client) SetDNSPreferences(ctx context.Context, magicDNS bool) (dnsResp *DNSPreferences, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetDNSPreferences: %w", err)
+		}
+	}()
+	dnsReq := DNSPreferences{MagicDNS: magicDNS}
+	b, err := c.dnsPOSTRequest(ctx, "preferences", dnsReq)
+	if err != nil {
+		return
+	}
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp, err
+}
+
+// SearchPaths retrieves the list of searchpaths set for a tailnet.
+func (c *Client) SearchPaths(ctx context.Context) (searchpaths []string, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SearchPaths: %w", err)
+		}
+	}()
+	b, err := c.dnsGETRequest(ctx, "searchpaths")
+	if err != nil {
+		return nil, err
+	}
+	var dnsResp *DNSSearchPaths
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp.SearchPaths, err
+}
+
+// SetSearchPaths sets the list of searchpaths for a tailnet.
+func (c *Client) SetSearchPaths(ctx context.Context, searchpaths []string) (newSearchPaths []string, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetSearchPaths: %w", err)
+		}
+	}()
+	dnsReq := DNSSearchPaths{SearchPaths: searchpaths}
+	b, err := c.dnsPOSTRequest(ctx, "searchpaths", dnsReq)
+	if err != nil {
+		return nil, err
+	}
+	var dnsResp DNSSearchPaths
+	err = json.Unmarshal(b, &dnsResp)
+	return dnsResp.SearchPaths, err
+}

client/tailscale/example/servetls/servetls.go

@@ -0,0 +1,28 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// The servetls program shows how to run an HTTPS server
+// using a Tailscale cert via LetsEncrypt.
+package main
+
+import (
+	"crypto/tls"
+	"io"
+	"log"
+	"net/http"
+
+	"tailscale.com/client/tailscale"
+)
+
+func main() {
+	s := &http.Server{
+		TLSConfig: &tls.Config{
+			GetCertificate: tailscale.GetCertificate,
+		},
+		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			io.WriteString(w, "<h1>Hello from Tailscale!</h1> It works.")
+		}),
+	}
+	log.Printf("Running TLS server on :443 ...")
+	log.Fatal(s.ListenAndServeTLS("", ""))
+}

client/tailscale/keys.go

@@ -0,0 +1,166 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// Key represents a Tailscale API or auth key.
+type Key struct {
+	ID           string          `json:"id"`
+	Created      time.Time       `json:"created"`
+	Expires      time.Time       `json:"expires"`
+	Capabilities KeyCapabilities `json:"capabilities"`
+}
+
+// KeyCapabilities are the capabilities of a Key.
+type KeyCapabilities struct {
+	Devices KeyDeviceCapabilities `json:"devices,omitempty"`
+}
+
+// KeyDeviceCapabilities are the device-related capabilities of a Key.
+type KeyDeviceCapabilities struct {
+	Create KeyDeviceCreateCapabilities `json:"create"`
+}
+
+// KeyDeviceCreateCapabilities are the device creation capabilities of a Key.
+type KeyDeviceCreateCapabilities struct {
+	Reusable      bool     `json:"reusable"`
+	Ephemeral     bool     `json:"ephemeral"`
+	Preauthorized bool     `json:"preauthorized"`
+	Tags          []string `json:"tags,omitempty"`
+}
+
+// Keys returns the list of keys for the current user.
+func (c *Client) Keys(ctx context.Context) ([]string, error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	var keys struct {
+		Keys []*Key `json:"keys"`
+	}
+	if err := json.Unmarshal(b, &keys); err != nil {
+		return nil, err
+	}
+	ret := make([]string, 0, len(keys.Keys))
+	for _, k := range keys.Keys {
+		ret = append(ret, k.ID)
+	}
+	return ret, nil
+}
+
+// CreateKey creates a new key for the current user. Currently, only auth keys
+// can be created. It returns the secret key itself, which cannot be retrieved again
+// later, and the key metadata.
+//
+// To create a key with a specific expiry, use CreateKeyWithExpiry.
+func (c *Client) CreateKey(ctx context.Context, caps KeyCapabilities) (keySecret string, keyMeta *Key, _ error) {
+	return c.CreateKeyWithExpiry(ctx, caps, 0)
+}
+
+// CreateKeyWithExpiry is like CreateKey, but allows specifying a expiration time.
+//
+// The time is truncated to a whole number of seconds. If zero, that means no expiration.
+func (c *Client) CreateKeyWithExpiry(ctx context.Context, caps KeyCapabilities, expiry time.Duration) (keySecret string, keyMeta *Key, _ error) {
+
+	// convert expirySeconds to an int64 (seconds)
+	expirySeconds := int64(expiry.Seconds())
+	if expirySeconds < 0 {
+		return "", nil, fmt.Errorf("expiry must be positive")
+	}
+	if expirySeconds == 0 && expiry != 0 {
+		return "", nil, fmt.Errorf("non-zero expiry must be at least one second")
+	}
+
+	keyRequest := struct {
+		Capabilities  KeyCapabilities `json:"capabilities"`
+		ExpirySeconds int64           `json:"expirySeconds,omitempty"`
+	}{caps, int64(expirySeconds)}
+	bs, err := json.Marshal(keyRequest)
+	if err != nil {
+		return "", nil, err
+	}
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys", c.baseURL(), c.tailnet)
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewReader(bs))
+	if err != nil {
+		return "", nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return "", nil, err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return "", nil, handleErrorResponse(b, resp)
+	}
+
+	var key struct {
+		Key
+		Secret string `json:"key"`
+	}
+	if err := json.Unmarshal(b, &key); err != nil {
+		return "", nil, err
+	}
+	return key.Secret, &key.Key, nil
+}
+
+// Key returns the metadata for the given key ID. Currently, capabilities are
+// only returned for auth keys, API keys only return general metadata.
+func (c *Client) Key(ctx context.Context, id string) (*Key, error) {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys/%s", c.baseURL(), c.tailnet, id)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	var key Key
+	if err := json.Unmarshal(b, &key); err != nil {
+		return nil, err
+	}
+	return &key, nil
+}
+
+// DeleteKey deletes the key with the given ID.
+func (c *Client) DeleteKey(ctx context.Context, id string) error {
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s/keys/%s", c.baseURL(), c.tailnet, id)
+	req, err := http.NewRequestWithContext(ctx, "DELETE", path, nil)
+	if err != nil {
+		return err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return handleErrorResponse(b, resp)
+	}
+	return nil
+}

client/tailscale/localclient_test.go

@@ -0,0 +1,27 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import "testing"
+
+func TestGetServeConfigFromJSON(t *testing.T) {
+	sc, err := getServeConfigFromJSON([]byte("null"))
+	if sc != nil {
+		t.Errorf("want nil for null")
+	}
+	if err != nil {
+		t.Errorf("reading null: %v", err)
+	}
+
+	sc, err = getServeConfigFromJSON([]byte(`{"TCP":{}}`))
+	if err != nil {
+		t.Errorf("reading object: %v", err)
+	} else if sc == nil {
+		t.Errorf("want non-nil for object")
+	} else if sc.TCP == nil {
+		t.Errorf("want non-nil TCP for object")
+	}
+}

client/tailscale/required_version.go

@@ -0,0 +1,10 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build !go1.20
+
+package tailscale
+
+func init() {
+	you_need_Go_1_20_to_compile_Tailscale()
+}

client/tailscale/routes.go

@@ -0,0 +1,95 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/netip"
+)
+
+// Routes contains the lists of subnet routes that are currently advertised by a device,
+// as well as the subnets that are enabled to be routed by the device.
+type Routes struct {
+	AdvertisedRoutes []netip.Prefix `json:"advertisedRoutes"`
+	EnabledRoutes    []netip.Prefix `json:"enabledRoutes"`
+}
+
+// Routes retrieves the list of subnet routes that have been enabled for a device.
+// The routes that are returned are not necessarily advertised by the device,
+// they have only been preapproved.
+func (c *Client) Routes(ctx context.Context, deviceID string) (routes *Routes, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.Routes: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/device/%s/routes", c.baseURL(), deviceID)
+	req, err := http.NewRequestWithContext(ctx, "GET", path, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	var sr Routes
+	err = json.Unmarshal(b, &sr)
+	return &sr, err
+}
+
+type postRoutesParams struct {
+	Routes []netip.Prefix `json:"routes"`
+}
+
+// SetRoutes updates the list of subnets that are enabled for a device.
+// Subnets must be parsable by net/netip.ParsePrefix.
+// Subnets do not have to be currently advertised by a device, they may be pre-enabled.
+// Returns the updated list of enabled and advertised subnet routes in a *Routes object.
+func (c *Client) SetRoutes(ctx context.Context, deviceID string, subnets []netip.Prefix) (routes *Routes, err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.SetRoutes: %w", err)
+		}
+	}()
+	params := &postRoutesParams{Routes: subnets}
+	data, err := json.Marshal(params)
+	if err != nil {
+		return nil, err
+	}
+	path := fmt.Sprintf("%s/api/v2/device/%s/routes", c.baseURL(), deviceID)
+	req, err := http.NewRequestWithContext(ctx, "POST", path, bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return nil, err
+	}
+	// If status code was not successful, return the error.
+	// TODO: Change the check for the StatusCode to include other 2XX success codes.
+	if resp.StatusCode != http.StatusOK {
+		return nil, handleErrorResponse(b, resp)
+	}
+
+	var srr *Routes
+	if err := json.Unmarshal(b, &srr); err != nil {
+		return nil, err
+	}
+	return srr, err
+}

client/tailscale/tailnet.go

@@ -0,0 +1,42 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build go1.19
+
+package tailscale
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"tailscale.com/util/httpm"
+)
+
+// TailnetDeleteRequest handles sending a DELETE request for a tailnet to control.
+func (c *Client) TailnetDeleteRequest(ctx context.Context, tailnetID string) (err error) {
+	defer func() {
+		if err != nil {
+			err = fmt.Errorf("tailscale.DeleteTailnet: %w", err)
+		}
+	}()
+
+	path := fmt.Sprintf("%s/api/v2/tailnet/%s", c.baseURL(), url.PathEscape(string(tailnetID)))
+	req, err := http.NewRequestWithContext(ctx, httpm.DELETE, path, nil)
+	if err != nil {
+		return err
+	}
+
+	c.setAuth(req)
+	b, resp, err := c.sendRequest(req)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return handleErrorResponse(b, resp)
+	}
+
+	return nil
+}

client/tailscale/tailscale.go

@@ -1,295 +1,157 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
-// Package tailscale contains Tailscale client code.
+//go:build go1.19
+
+// Package tailscale contains Go clients for the Tailscale LocalAPI and
+// Tailscale control plane API.
+//
+// Warning: this package is in development and makes no API compatibility
+// promises as of 2022-04-29. It is subject to change at any time.
 package tailscale
 
 import (
-	"bytes"
-	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
-	"net"
 	"net/http"
-	"net/url"
-	"strconv"
-	"strings"
-
-	"tailscale.com/client/tailscale/apitype"
-	"tailscale.com/ipn"
-	"tailscale.com/ipn/ipnstate"
-	"tailscale.com/paths"
-	"tailscale.com/safesocket"
-	"tailscale.com/tailcfg"
 )
 
-// TailscaledSocket is the tailscaled Unix socket.
-var TailscaledSocket = paths.DefaultTailscaledSocket()
-
-// tsClient does HTTP requests to the local Tailscale daemon.
-var tsClient = &http.Client{
-	Transport: &http.Transport{
-		DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
-			if addr != "local-tailscaled.sock:80" {
-				return nil, fmt.Errorf("unexpected URL address %q", addr)
-			}
-			if TailscaledSocket == paths.DefaultTailscaledSocket() {
-				// On macOS, when dialing from non-sandboxed program to sandboxed GUI running
-				// a TCP server on a random port, find the random port. For HTTP connections,
-				// we don't send the token. It gets added in an HTTP Basic-Auth header.
-				if port, _, err := safesocket.LocalTCPPortAndToken(); err == nil {
-					var d net.Dialer
-					return d.DialContext(ctx, "tcp", "localhost:"+strconv.Itoa(port))
-				}
-			}
-			return safesocket.Connect(TailscaledSocket, 41112)
-		},
-	},
-}
-
-// DoLocalRequest makes an HTTP request to the local machine's Tailscale daemon.
+// I_Acknowledge_This_API_Is_Unstable must be set true to use this package
+// for now. It was added 2022-04-29 when it was moved to this git repo
+// and will be removed when the public API has settled.
 //
-// URLs are of the form http://local-tailscaled.sock/localapi/v0/whois?ip=1.2.3.4.
+// TODO(bradfitz): remove this after the we're happy with the public API.
+var I_Acknowledge_This_API_Is_Unstable = false
+
+// TODO: use url.PathEscape() for deviceID and tailnets when constructing requests.
+
+const defaultAPIBase = "https://api.tailscale.com"
+
+// maxSize is the maximum read size (10MB) of responses from the server.
+const maxReadSize = 10 << 20
+
+// Client makes API calls to the Tailscale control plane API server.
 //
-// The hostname must be "local-tailscaled.sock", even though it
-// doesn't actually do any DNS lookup. The actual means of connecting to and
-// authenticating to the local Tailscale daemon vary by platform.
+// Use NewClient to instantiate one. Exported fields should be set before
+// the client is used and not changed thereafter.
+type Client struct {
+	// tailnet is the globally unique identifier for a Tailscale network, such
+	// as "example.com" or "user@gmail.com".
+	tailnet string
+	// auth is the authentication method to use for this client.
+	// nil means none, which generally won't work, but won't crash.
+	auth AuthMethod
+
+	// BaseURL optionally specifies an alternate API server to use.
+	// If empty, "https://api.tailscale.com" is used.
+	BaseURL string
+
+	// HTTPClient optionally specifies an alternate HTTP client to use.
+	// If nil, http.DefaultClient is used.
+	HTTPClient *http.Client
+}
+
+func (c *Client) httpClient() *http.Client {
+	if c.HTTPClient != nil {
+		return c.HTTPClient
+	}
+	return http.DefaultClient
+}
+
+func (c *Client) baseURL() string {
+	if c.BaseURL != "" {
+		return c.BaseURL
+	}
+	return defaultAPIBase
+}
+
+// AuthMethod is the interface for API authentication methods.
 //
-// DoLocalRequest may mutate the request to add Authorization headers.
-func DoLocalRequest(req *http.Request) (*http.Response, error) {
-	if _, token, err := safesocket.LocalTCPPortAndToken(); err == nil {
-		req.SetBasicAuth("", token)
+// Most users will use AuthKey.
+type AuthMethod interface {
+	modifyRequest(req *http.Request)
+}
+
+// APIKey is an AuthMethod for NewClient that authenticates requests
+// using an authkey.
+type APIKey string
+
+func (ak APIKey) modifyRequest(req *http.Request) {
+	req.SetBasicAuth(string(ak), "")
+}
+
+func (c *Client) setAuth(r *http.Request) {
+	if c.auth != nil {
+		c.auth.modifyRequest(r)
 	}
-	return tsClient.Do(req)
 }
 
-type errorJSON struct {
-	Error string
-}
-
-// bestError returns either err, or if body contains a valid JSON
-// object of type errorJSON, its non-empty error body.
-func bestError(err error, body []byte) error {
-	var j errorJSON
-	if err := json.Unmarshal(body, &j); err == nil && j.Error != "" {
-		return errors.New(j.Error)
+// NewClient is a convenience method for instantiating a new Client.
+//
+// tailnet is the globally unique identifier for a Tailscale network, such
+// as "example.com" or "user@gmail.com".
+// If httpClient is nil, then http.DefaultClient is used.
+// "api.tailscale.com" is set as the BaseURL for the returned client
+// and can be changed manually by the user.
+func NewClient(tailnet string, auth AuthMethod) *Client {
+	return &Client{
+		tailnet: tailnet,
+		auth:    auth,
 	}
-	return err
 }
 
-func send(ctx context.Context, method, path string, wantStatus int, body io.Reader) ([]byte, error) {
-	req, err := http.NewRequestWithContext(ctx, method, "http://local-tailscaled.sock"+path, body)
+func (c *Client) Tailnet() string { return c.tailnet }
+
+// Do sends a raw HTTP request, after adding any authentication headers.
+func (c *Client) Do(req *http.Request) (*http.Response, error) {
+	if !I_Acknowledge_This_API_Is_Unstable {
+		return nil, errors.New("use of Client without setting I_Acknowledge_This_API_Is_Unstable")
+	}
+	c.setAuth(req)
+	return c.httpClient().Do(req)
+}
+
+// sendRequest add the authentication key to the request and sends it. It
+// receives the response and reads up to 10MB of it.
+func (c *Client) sendRequest(req *http.Request) ([]byte, *http.Response, error) {
+	if !I_Acknowledge_This_API_Is_Unstable {
+		return nil, nil, errors.New("use of Client without setting I_Acknowledge_This_API_Is_Unstable")
+	}
+	c.setAuth(req)
+	resp, err := c.httpClient().Do(req)
 	if err != nil {
-		return nil, err
+		return nil, resp, err
 	}
-	res, err := DoLocalRequest(req)
-	if err != nil {
-		return nil, err
+	defer resp.Body.Close()
+
+	// Read response. Limit the response to 10MB.
+	body := io.LimitReader(resp.Body, maxReadSize+1)
+	b, err := io.ReadAll(body)
+	if len(b) > maxReadSize {
+		err = errors.New("API response too large")
 	}
-	defer res.Body.Close()
-	slurp, err := ioutil.ReadAll(res.Body)
-	if err != nil {
-		return nil, err
-	}
-	if res.StatusCode != wantStatus {
-		err := fmt.Errorf("HTTP %s: %s (expected %v)", res.Status, slurp, wantStatus)
-		return nil, bestError(err, slurp)
-	}
-	return slurp, nil
+	return b, resp, err
 }
 
-func get200(ctx context.Context, path string) ([]byte, error) {
-	return send(ctx, "GET", path, 200, nil)
+// ErrResponse is the HTTP error returned by the Tailscale server.
+type ErrResponse struct {
+	Status  int
+	Message string
 }
 
-// WhoIs returns the owner of the remoteAddr, which must be an IP or IP:port.
-func WhoIs(ctx context.Context, remoteAddr string) (*apitype.WhoIsResponse, error) {
-	body, err := get200(ctx, "/localapi/v0/whois?addr="+url.QueryEscape(remoteAddr))
-	if err != nil {
-		return nil, err
-	}
-	r := new(apitype.WhoIsResponse)
-	if err := json.Unmarshal(body, r); err != nil {
-		if max := 200; len(body) > max {
-			body = append(body[:max], "..."...)
-		}
-		return nil, fmt.Errorf("failed to parse JSON WhoIsResponse from %q", body)
-	}
-	return r, nil
+func (e ErrResponse) Error() string {
+	return fmt.Sprintf("Status: %d, Message: %q", e.Status, e.Message)
 }
 
-// Goroutines returns a dump of the Tailscale daemon's current goroutines.
-func Goroutines(ctx context.Context) ([]byte, error) {
-	return get200(ctx, "/localapi/v0/goroutines")
-}
-
-// BugReport logs and returns a log marker that can be shared by the user with support.
-func BugReport(ctx context.Context, note string) (string, error) {
-	body, err := send(ctx, "POST", "/localapi/v0/bugreport?note="+url.QueryEscape(note), 200, nil)
-	if err != nil {
-		return "", err
-	}
-	return strings.TrimSpace(string(body)), nil
-}
-
-// Status returns the Tailscale daemon's status.
-func Status(ctx context.Context) (*ipnstate.Status, error) {
-	return status(ctx, "")
-}
-
-// StatusWithPeers returns the Tailscale daemon's status, without the peer info.
-func StatusWithoutPeers(ctx context.Context) (*ipnstate.Status, error) {
-	return status(ctx, "?peers=false")
-}
-
-func status(ctx context.Context, queryString string) (*ipnstate.Status, error) {
-	body, err := get200(ctx, "/localapi/v0/status"+queryString)
-	if err != nil {
-		return nil, err
-	}
-	st := new(ipnstate.Status)
-	if err := json.Unmarshal(body, st); err != nil {
-		return nil, err
-	}
-	return st, nil
-}
-
-func WaitingFiles(ctx context.Context) ([]apitype.WaitingFile, error) {
-	body, err := get200(ctx, "/localapi/v0/files/")
-	if err != nil {
-		return nil, err
-	}
-	var wfs []apitype.WaitingFile
-	if err := json.Unmarshal(body, &wfs); err != nil {
-		return nil, err
-	}
-	return wfs, nil
-}
-
-func DeleteWaitingFile(ctx context.Context, baseName string) error {
-	_, err := send(ctx, "DELETE", "/localapi/v0/files/"+url.PathEscape(baseName), http.StatusNoContent, nil)
-	return err
-}
-
-func GetWaitingFile(ctx context.Context, baseName string) (rc io.ReadCloser, size int64, err error) {
-	req, err := http.NewRequestWithContext(ctx, "GET", "http://local-tailscaled.sock/localapi/v0/files/"+url.PathEscape(baseName), nil)
-	if err != nil {
-		return nil, 0, err
-	}
-	res, err := DoLocalRequest(req)
-	if err != nil {
-		return nil, 0, err
-	}
-	if res.ContentLength == -1 {
-		res.Body.Close()
-		return nil, 0, fmt.Errorf("unexpected chunking")
-	}
-	if res.StatusCode != 200 {
-		body, _ := ioutil.ReadAll(res.Body)
-		res.Body.Close()
-		return nil, 0, fmt.Errorf("HTTP %s: %s", res.Status, body)
-	}
-	return res.Body, res.ContentLength, nil
-}
-
-func FileTargets(ctx context.Context) ([]apitype.FileTarget, error) {
-	body, err := get200(ctx, "/localapi/v0/file-targets")
-	if err != nil {
-		return nil, err
-	}
-	var fts []apitype.FileTarget
-	if err := json.Unmarshal(body, &fts); err != nil {
-		return nil, fmt.Errorf("invalid JSON: %w", err)
-	}
-	return fts, nil
-}
-
-func CheckIPForwarding(ctx context.Context) error {
-	body, err := get200(ctx, "/localapi/v0/check-ip-forwarding")
-	if err != nil {
+// handleErrorResponse decodes the error message from the server and returns
+// an ErrResponse from it.
+func handleErrorResponse(b []byte, resp *http.Response) error {
+	var errResp ErrResponse
+	if err := json.Unmarshal(b, &errResp); err != nil {
 		return err
 	}
-	var jres struct {
-		Warning string
-	}
-	if err := json.Unmarshal(body, &jres); err != nil {
-		return fmt.Errorf("invalid JSON from check-ip-forwarding: %w", err)
-	}
-	if jres.Warning != "" {
-		return errors.New(jres.Warning)
-	}
-	return nil
-}
-
-func GetPrefs(ctx context.Context) (*ipn.Prefs, error) {
-	body, err := get200(ctx, "/localapi/v0/prefs")
-	if err != nil {
-		return nil, err
-	}
-	var p ipn.Prefs
-	if err := json.Unmarshal(body, &p); err != nil {
-		return nil, fmt.Errorf("invalid prefs JSON: %w", err)
-	}
-	return &p, nil
-}
-
-func EditPrefs(ctx context.Context, mp *ipn.MaskedPrefs) (*ipn.Prefs, error) {
-	mpj, err := json.Marshal(mp)
-	if err != nil {
-		return nil, err
-	}
-	body, err := send(ctx, "PATCH", "/localapi/v0/prefs", http.StatusOK, bytes.NewReader(mpj))
-	if err != nil {
-		return nil, err
-	}
-	var p ipn.Prefs
-	if err := json.Unmarshal(body, &p); err != nil {
-		return nil, fmt.Errorf("invalid prefs JSON: %w", err)
-	}
-	return &p, nil
-}
-
-func Logout(ctx context.Context) error {
-	_, err := send(ctx, "POST", "/localapi/v0/logout", http.StatusNoContent, nil)
-	return err
-}
-
-// SetDNS adds a DNS TXT record for the given domain name, containing
-// the provided TXT value. The intended use case is answering
-// LetsEncrypt/ACME dns-01 challenges.
-//
-// The control plane will only permit SetDNS requests with very
-// specific names and values. The name should be
-// "_acme-challenge." + your node's MagicDNS name. It's expected that
-// clients cache the certs from LetsEncrypt (or whichever CA is
-// providing them) and only request new ones as needed; the control plane
-// rate limits SetDNS requests.
-//
-// This is a low-level interface; it's expected that most Tailscale
-// users use a higher level interface to getting/using TLS
-// certificates.
-func SetDNS(ctx context.Context, name, value string) error {
-	v := url.Values{}
-	v.Set("name", name)
-	v.Set("value", value)
-	_, err := send(ctx, "POST", "/localapi/v0/set-dns?"+v.Encode(), 200, nil)
-	return err
-}
-
-// CurrentDERPMap returns the current DERPMap that is being used by the local tailscaled.
-// It is intended to be used with netcheck to see availability of DERPs.
-func CurrentDERPMap(ctx context.Context) (*tailcfg.DERPMap, error) {
-	var derpMap tailcfg.DERPMap
-	res, err := send(ctx, "GET", "/localapi/v0/derpmap", 200, nil)
-	if err != nil {
-		return nil, err
-	}
-	if err = json.Unmarshal(res, &derpMap); err != nil {
-		return nil, fmt.Errorf("invalid derp map json: %w", err)
-	}
-	return &derpMap, nil
+	errResp.Status = resp.StatusCode
+	return errResp
 }

cmd/addlicense/main.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // Program addlicense adds a license header to a file.
 // It is intended for use with 'go generate',
@@ -15,26 +14,24 @@ import (
 )
 
 var (
-	year = flag.Int("year", 0, "copyright year")
 	file = flag.String("file", "", "file to modify")
 )
 
 func usage() {
 	fmt.Fprintf(os.Stderr, `
-usage: addlicense -year YEAR -file FILE <subcommand args...>
+usage: addlicense -file FILE <subcommand args...>
 `[1:])
 
 	flag.PrintDefaults()
 	fmt.Fprintf(os.Stderr, `
-addlicense adds a Tailscale license to the beginning of file,
-using year as the copyright year.
+addlicense adds a Tailscale license to the beginning of file.
 
 It is intended for use with 'go generate', so it also runs a subcommand,
 which presumably creates the file.
 
 Sample usage:
 
-addlicense -year 2021 -file pull_strings.go stringer -type=pull
+addlicense -file pull_strings.go stringer -type=pull
 `[1:])
 	os.Exit(2)
 }
@@ -54,7 +51,7 @@ func main() {
 	check(err)
 	f, err := os.OpenFile(*file, os.O_TRUNC|os.O_WRONLY, 0644)
 	check(err)
-	_, err = fmt.Fprintf(f, license, *year)
+	_, err = fmt.Fprint(f, license)
 	check(err)
 	_, err = f.Write(b)
 	check(err)
@@ -70,8 +67,7 @@ func check(err error) {
 }
 
 var license = `
-// Copyright (c) %d Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 `[1:]

cmd/cloner/cloner.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // Cloner is a tool to automate the creation of a Clone method.
 //
@@ -17,21 +16,16 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
-	"go/ast"
-	"go/format"
-	"go/token"
 	"go/types"
-	"io/ioutil"
 	"log"
 	"os"
 	"strings"
 
-	"golang.org/x/tools/go/packages"
+	"tailscale.com/util/codegen"
 )
 
 var (
 	flagTypes     = flag.String("type", "", "comma-separated list of types; required")
-	flagOutput    = flag.String("output", "", "output file; required")
 	flagBuildTags = flag.String("tags", "", "compiler build tags to apply")
 	flagCloneFunc = flag.Bool("clonefunc", false, "add a top-level Clone func")
 )
@@ -46,64 +40,28 @@ func main() {
 	}
 	typeNames := strings.Split(*flagTypes, ",")
 
-	cfg := &packages.Config{
-		Mode:  packages.NeedTypes | packages.NeedTypesInfo | packages.NeedSyntax | packages.NeedName,
-		Tests: false,
-	}
-	if *flagBuildTags != "" {
-		cfg.BuildFlags = []string{"-tags=" + *flagBuildTags}
-	}
-	pkgs, err := packages.Load(cfg, ".")
+	pkg, namedTypes, err := codegen.LoadTypes(*flagBuildTags, ".")
 	if err != nil {
 		log.Fatal(err)
 	}
-	if len(pkgs) != 1 {
-		log.Fatalf("wrong number of packages: %d", len(pkgs))
-	}
-	pkg := pkgs[0]
+	it := codegen.NewImportTracker(pkg.Types)
 	buf := new(bytes.Buffer)
-	imports := make(map[string]struct{})
 	for _, typeName := range typeNames {
-		found := false
-		for _, file := range pkg.Syntax {
-			//var fbuf bytes.Buffer
-			//ast.Fprint(&fbuf, pkg.Fset, file, nil)
-			//fmt.Println(fbuf.String())
-
-			for _, d := range file.Decls {
-				decl, ok := d.(*ast.GenDecl)
-				if !ok || decl.Tok != token.TYPE {
-					continue
-				}
-				for _, s := range decl.Specs {
-					spec, ok := s.(*ast.TypeSpec)
-					if !ok || spec.Name.Name != typeName {
-						continue
-					}
-					typeNameObj := pkg.TypesInfo.Defs[spec.Name]
-					typ, ok := typeNameObj.Type().(*types.Named)
-					if !ok {
-						continue
-					}
-					pkg := typeNameObj.Pkg()
-					gen(buf, imports, typeName, typ, pkg)
-					found = true
-				}
-			}
-		}
-		if !found {
+		typ, ok := namedTypes[typeName]
+		if !ok {
 			log.Fatalf("could not find type %s", typeName)
 		}
+		gen(buf, it, typ)
 	}
 
-	w := func(format string, args ...interface{}) {
+	w := func(format string, args ...any) {
 		fmt.Fprintf(buf, format+"\n", args...)
 	}
 	if *flagCloneFunc {
 		w("// Clone duplicates src into dst and reports whether it succeeded.")
 		w("// To succeed, <src, dst> must be of types <*T, *T> or <*T, **T>,")
 		w("// where T is one of %s.", *flagTypes)
-		w("func Clone(dst, src interface{}) bool {")
+		w("func Clone(dst, src any) bool {")
 		w("	switch src := src.(type) {")
 		for _, typeName := range typeNames {
 			w("	case *%s:", typeName)
@@ -120,156 +78,117 @@ func main() {
 		w("	return false")
 		w("}")
 	}
-
-	contents := new(bytes.Buffer)
-	fmt.Fprintf(contents, header, *flagTypes, pkg.Name)
-	fmt.Fprintf(contents, "import (\n")
-	for s := range imports {
-		fmt.Fprintf(contents, "\t%q\n", s)
-	}
-	fmt.Fprintf(contents, ")\n\n")
-	contents.Write(buf.Bytes())
-
-	out, err := format.Source(contents.Bytes())
-	if err != nil {
-		log.Fatalf("%s, in source:\n%s", err, contents.Bytes())
-	}
-
-	output := *flagOutput
-	if output == "" {
-		flag.Usage()
-		os.Exit(2)
-	}
-	if err := ioutil.WriteFile(output, out, 0644); err != nil {
+	cloneOutput := pkg.Name + "_clone.go"
+	if err := codegen.WritePackageFile("tailscale.com/cmd/cloner", pkg, cloneOutput, it, buf); err != nil {
 		log.Fatal(err)
 	}
 }
 
-const header = `// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Code generated by tailscale.com/cmd/cloner -type %s; DO NOT EDIT.
-
-package %s
-
-`
-
-func gen(buf *bytes.Buffer, imports map[string]struct{}, name string, typ *types.Named, thisPkg *types.Package) {
-	pkgQual := func(pkg *types.Package) string {
-		if thisPkg == pkg {
-			return ""
-		}
-		imports[pkg.Path()] = struct{}{}
-		return pkg.Name()
-	}
-	importedName := func(t types.Type) string {
-		return types.TypeString(t, pkgQual)
+func gen(buf *bytes.Buffer, it *codegen.ImportTracker, typ *types.Named) {
+	t, ok := typ.Underlying().(*types.Struct)
+	if !ok {
+		return
 	}
 
-	switch t := typ.Underlying().(type) {
-	case *types.Struct:
-		// We generate two bits of code simultaneously while we walk the struct.
-		// One is the Clone method itself, which we write directly to buf.
-		// The other is a variable assignment that will fail if the struct
-		// changes without the Clone method getting regenerated.
-		// We write that to regenBuf, and then append it to buf at the end.
-		regenBuf := new(bytes.Buffer)
-		writeRegen := func(format string, args ...interface{}) {
-			fmt.Fprintf(regenBuf, format+"\n", args...)
+	name := typ.Obj().Name()
+	fmt.Fprintf(buf, "// Clone makes a deep copy of %s.\n", name)
+	fmt.Fprintf(buf, "// The result aliases no memory with the original.\n")
+	fmt.Fprintf(buf, "func (src *%s) Clone() *%s {\n", name, name)
+	writef := func(format string, args ...any) {
+		fmt.Fprintf(buf, "\t"+format+"\n", args...)
+	}
+	writef("if src == nil {")
+	writef("\treturn nil")
+	writef("}")
+	writef("dst := new(%s)", name)
+	writef("*dst = *src")
+	for i := 0; i < t.NumFields(); i++ {
+		fname := t.Field(i).Name()
+		ft := t.Field(i).Type()
+		if !codegen.ContainsPointers(ft) || codegen.HasNoClone(t.Tag(i)) {
+			continue
 		}
-		writeRegen("// A compilation failure here means this code must be regenerated, with command:")
-		writeRegen("//   tailscale.com/cmd/cloner -type %s", *flagTypes)
-		writeRegen("var _%sNeedsRegeneration = %s(struct {", name, name)
-
-		name := typ.Obj().Name()
-		fmt.Fprintf(buf, "// Clone makes a deep copy of %s.\n", name)
-		fmt.Fprintf(buf, "// The result aliases no memory with the original.\n")
-		fmt.Fprintf(buf, "func (src *%s) Clone() *%s {\n", name, name)
-		writef := func(format string, args ...interface{}) {
-			fmt.Fprintf(buf, "\t"+format+"\n", args...)
-		}
-		writef("if src == nil {")
-		writef("\treturn nil")
-		writef("}")
-		writef("dst := new(%s)", name)
-		writef("*dst = *src")
-		for i := 0; i < t.NumFields(); i++ {
-			fname := t.Field(i).Name()
-			ft := t.Field(i).Type()
-
-			writeRegen("\t%s %s", fname, importedName(ft))
-
-			if !containsPointers(ft) {
+		if named, _ := ft.(*types.Named); named != nil {
+			if codegen.IsViewType(ft) {
+				writef("dst.%s = src.%s", fname, fname)
 				continue
 			}
-			if named, _ := ft.(*types.Named); named != nil && !hasBasicUnderlying(ft) {
+			if !hasBasicUnderlying(ft) {
 				writef("dst.%s = *src.%s.Clone()", fname, fname)
 				continue
 			}
-			switch ft := ft.Underlying().(type) {
-			case *types.Slice:
-				if containsPointers(ft.Elem()) {
-					n := importedName(ft.Elem())
-					writef("dst.%s = make([]%s, len(src.%s))", fname, n, fname)
-					writef("for i := range dst.%s {", fname)
-					if _, isPtr := ft.Elem().(*types.Pointer); isPtr {
-						writef("\tdst.%s[i] = src.%s[i].Clone()", fname, fname)
-					} else {
-						writef("\tdst.%s[i] = *src.%s[i].Clone()", fname, fname)
-					}
-					writef("}")
-				} else {
-					writef("dst.%s = append(src.%s[:0:0], src.%s...)", fname, fname, fname)
-				}
-			case *types.Pointer:
-				if named, _ := ft.Elem().(*types.Named); named != nil && containsPointers(ft.Elem()) {
-					writef("dst.%s = src.%s.Clone()", fname, fname)
-					continue
-				}
-				n := importedName(ft.Elem())
-				writef("if dst.%s != nil {", fname)
-				writef("\tdst.%s = new(%s)", fname, n)
-				writef("\t*dst.%s = *src.%s", fname, fname)
-				if containsPointers(ft.Elem()) {
-					writef("\t" + `panic("TODO pointers in pointers")`)
-				}
-				writef("}")
-			case *types.Map:
-				writef("if dst.%s != nil {", fname)
-				writef("\tdst.%s = map[%s]%s{}", fname, importedName(ft.Key()), importedName(ft.Elem()))
-				if sliceType, isSlice := ft.Elem().(*types.Slice); isSlice {
-					n := importedName(sliceType.Elem())
-					writef("\tfor k := range src.%s {", fname)
-					// use zero-length slice instead of nil to ensure
-					// the key is always copied.
-					writef("\t\tdst.%s[k] = append([]%s{}, src.%s[k]...)", fname, n, fname)
-					writef("\t}")
-				} else if containsPointers(ft.Elem()) {
-					writef("\tfor k, v := range src.%s {", fname)
-					writef("\t\tdst.%s[k] = v.Clone()", fname)
-					writef("\t}")
-				} else {
-					writef("\tfor k, v := range src.%s {", fname)
-					writef("\t\tdst.%s[k] = v", fname)
-					writef("\t}")
-				}
-				writef("}")
-			case *types.Struct:
-				writef(`panic("TODO struct %s")`, fname)
-			default:
-				writef(`panic(fmt.Sprintf("TODO: %T", ft))`)
-			}
 		}
-		writef("return dst")
-		fmt.Fprintf(buf, "}\n\n")
-
-		writeRegen("}{})\n")
-
-		buf.Write(regenBuf.Bytes())
+		switch ft := ft.Underlying().(type) {
+		case *types.Slice:
+			if codegen.ContainsPointers(ft.Elem()) {
+				n := it.QualifiedName(ft.Elem())
+				writef("dst.%s = make([]%s, len(src.%s))", fname, n, fname)
+				writef("for i := range dst.%s {", fname)
+				if ptr, isPtr := ft.Elem().(*types.Pointer); isPtr {
+					if _, isBasic := ptr.Elem().Underlying().(*types.Basic); isBasic {
+						writef("\tx := *src.%s[i]", fname)
+						writef("\tdst.%s[i] = &x", fname)
+					} else {
+						writef("\tdst.%s[i] = src.%s[i].Clone()", fname, fname)
+					}
+				} else {
+					writef("\tdst.%s[i] = *src.%s[i].Clone()", fname, fname)
+				}
+				writef("}")
+			} else {
+				writef("dst.%s = append(src.%s[:0:0], src.%s...)", fname, fname, fname)
+			}
+		case *types.Pointer:
+			if named, _ := ft.Elem().(*types.Named); named != nil && codegen.ContainsPointers(ft.Elem()) {
+				writef("dst.%s = src.%s.Clone()", fname, fname)
+				continue
+			}
+			n := it.QualifiedName(ft.Elem())
+			writef("if dst.%s != nil {", fname)
+			writef("\tdst.%s = new(%s)", fname, n)
+			writef("\t*dst.%s = *src.%s", fname, fname)
+			if codegen.ContainsPointers(ft.Elem()) {
+				writef("\t" + `panic("TODO pointers in pointers")`)
+			}
+			writef("}")
+		case *types.Map:
+			elem := ft.Elem()
+			writef("if dst.%s != nil {", fname)
+			writef("\tdst.%s = map[%s]%s{}", fname, it.QualifiedName(ft.Key()), it.QualifiedName(elem))
+			if sliceType, isSlice := elem.(*types.Slice); isSlice {
+				n := it.QualifiedName(sliceType.Elem())
+				writef("\tfor k := range src.%s {", fname)
+				// use zero-length slice instead of nil to ensure
+				// the key is always copied.
+				writef("\t\tdst.%s[k] = append([]%s{}, src.%s[k]...)", fname, n, fname)
+				writef("\t}")
+			} else if codegen.ContainsPointers(elem) {
+				writef("\tfor k, v := range src.%s {", fname)
+				switch elem.(type) {
+				case *types.Pointer:
+					writef("\t\tdst.%s[k] = v.Clone()", fname)
+				default:
+					writef("\t\tv2 := v.Clone()")
+					writef("\t\tdst.%s[k] = *v2", fname)
+				}
+				writef("\t}")
+			} else {
+				writef("\tfor k, v := range src.%s {", fname)
+				writef("\t\tdst.%s[k] = v", fname)
+				writef("\t}")
+			}
+			writef("}")
+		default:
+			writef(`panic("TODO: %s (%T)")`, fname, ft)
+		}
 	}
+	writef("return dst")
+	fmt.Fprintf(buf, "}\n\n")
+
+	buf.Write(codegen.AssertStructUnchanged(t, name, "Clone", it))
 }
 
+// hasBasicUnderlying reports true when typ.Underlying() is a slice or a map.
 func hasBasicUnderlying(typ types.Type) bool {
 	switch typ.Underlying().(type) {
 	case *types.Slice, *types.Map:
@@ -278,34 +197,3 @@ func hasBasicUnderlying(typ types.Type) bool {
 		return false
 	}
 }
-
-func containsPointers(typ types.Type) bool {
-	switch typ.String() {
-	case "time.Time":
-		// time.Time contains a pointer that does not need copying
-		return false
-	case "inet.af/netaddr.IP":
-		return false
-	}
-	switch ft := typ.Underlying().(type) {
-	case *types.Array:
-		return containsPointers(ft.Elem())
-	case *types.Chan:
-		return true
-	case *types.Interface:
-		return true // a little too broad
-	case *types.Map:
-		return true
-	case *types.Pointer:
-		return true
-	case *types.Slice:
-		return true
-	case *types.Struct:
-		for i := 0; i < ft.NumFields(); i++ {
-			if containsPointers(ft.Field(i).Type()) {
-				return true
-			}
-		}
-	}
-	return false
-}

cmd/containerboot/kube.go

@@ -0,0 +1,97 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build linux
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+
+	"tailscale.com/kube"
+	"tailscale.com/tailcfg"
+)
+
+// findKeyInKubeSecret inspects the kube secret secretName for a data
+// field called "authkey", and returns its value if present.
+func findKeyInKubeSecret(ctx context.Context, secretName string) (string, error) {
+	s, err := kc.GetSecret(ctx, secretName)
+	if err != nil {
+		return "", err
+	}
+	ak, ok := s.Data["authkey"]
+	if !ok {
+		return "", nil
+	}
+	return string(ak), nil
+}
+
+// storeDeviceInfo writes deviceID into the "device_id" data field of the kube
+// secret secretName.
+func storeDeviceInfo(ctx context.Context, secretName string, deviceID tailcfg.StableNodeID, fqdn string) error {
+	// First check if the secret exists at all. Even if running on
+	// kubernetes, we do not necessarily store state in a k8s secret.
+	if _, err := kc.GetSecret(ctx, secretName); err != nil {
+		if s, ok := err.(*kube.Status); ok {
+			if s.Code >= 400 && s.Code <= 499 {
+				// Assume the secret doesn't exist, or we don't have
+				// permission to access it.
+				return nil
+			}
+		}
+		return err
+	}
+
+	m := &kube.Secret{
+		Data: map[string][]byte{
+			"device_id":   []byte(deviceID),
+			"device_fqdn": []byte(fqdn),
+		},
+	}
+	return kc.StrategicMergePatchSecret(ctx, secretName, m, "tailscale-container")
+}
+
+// deleteAuthKey deletes the 'authkey' field of the given kube
+// secret. No-op if there is no authkey in the secret.
+func deleteAuthKey(ctx context.Context, secretName string) error {
+	// m is a JSON Patch data structure, see https://jsonpatch.com/ or RFC 6902.
+	m := []kube.JSONPatch{
+		{
+			Op:   "remove",
+			Path: "/data/authkey",
+		},
+	}
+	if err := kc.JSONPatchSecret(ctx, secretName, m); err != nil {
+		if s, ok := err.(*kube.Status); ok && s.Code == http.StatusUnprocessableEntity {
+			// This is kubernetes-ese for "the field you asked to
+			// delete already doesn't exist", aka no-op.
+			return nil
+		}
+		return err
+	}
+	return nil
+}
+
+var kc *kube.Client
+
+func initKube(root string) {
+	if root != "/" {
+		// If we are running in a test, we need to set the root path to the fake
+		// service account directory.
+		kube.SetRootPathForTesting(root)
+	}
+	var err error
+	kc, err = kube.New()
+	if err != nil {
+		log.Fatalf("Error creating kube client: %v", err)
+	}
+	if root != "/" {
+		// If we are running in a test, we need to set the URL to the
+		// httptest server.
+		kc.SetURL(fmt.Sprintf("https://%s:%s", os.Getenv("KUBERNETES_SERVICE_HOST"), os.Getenv("KUBERNETES_SERVICE_PORT_HTTPS")))
+	}
+}

cmd/containerboot/main.go

@@ -0,0 +1,578 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build linux
+
+// The containerboot binary is a wrapper for starting tailscaled in a container.
+// It handles reading the desired mode of operation out of environment
+// variables, bringing up and authenticating Tailscale, and any other
+// kubernetes-specific side jobs.
+//
+// As with most container things, configuration is passed through environment
+// variables. All configuration is optional.
+//
+//   - TS_AUTHKEY: the authkey to use for login.
+//   - TS_HOSTNAME: the hostname to request for the node.
+//   - TS_ROUTES: subnet routes to advertise.
+//   - TS_DEST_IP: proxy all incoming Tailscale traffic to the given
+//     destination.
+//   - TS_TAILSCALED_EXTRA_ARGS: extra arguments to 'tailscaled'.
+//   - TS_EXTRA_ARGS: extra arguments to 'tailscale up'.
+//   - TS_USERSPACE: run with userspace networking (the default)
+//     instead of kernel networking.
+//   - TS_STATE_DIR: the directory in which to store tailscaled
+//     state. The data should persist across container
+//     restarts.
+//   - TS_ACCEPT_DNS: whether to use the tailnet's DNS configuration.
+//   - TS_KUBE_SECRET: the name of the Kubernetes secret in which to
+//     store tailscaled state.
+//   - TS_SOCKS5_SERVER: the address on which to listen for SOCKS5
+//     proxying into the tailnet.
+//   - TS_OUTBOUND_HTTP_PROXY_LISTEN: the address on which to listen
+//     for HTTP proxying into the tailnet.
+//   - TS_SOCKET: the path where the tailscaled LocalAPI socket should
+//     be created.
+//   - TS_AUTH_ONCE: if true, only attempt to log in if not already
+//     logged in. If false (the default, for backwards
+//     compatibility), forcibly log in every time the
+//     container starts.
+//
+// When running on Kubernetes, containerboot defaults to storing state in the
+// "tailscale" kube secret. To store state on local disk instead, set
+// TS_KUBE_SECRET="" and TS_STATE_DIR=/path/to/storage/dir. The state dir should
+// be persistent storage.
+//
+// Additionally, if TS_AUTHKEY is not set and the TS_KUBE_SECRET contains an
+// "authkey" field, that key is used as the tailscale authkey.
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io/fs"
+	"log"
+	"net/netip"
+	"os"
+	"os/exec"
+	"os/signal"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+	"time"
+
+	"golang.org/x/sys/unix"
+	"tailscale.com/client/tailscale"
+	"tailscale.com/ipn"
+	"tailscale.com/util/deephash"
+)
+
+func main() {
+	log.SetPrefix("boot: ")
+	tailscale.I_Acknowledge_This_API_Is_Unstable = true
+
+	cfg := &settings{
+		AuthKey:         defaultEnvs([]string{"TS_AUTHKEY", "TS_AUTH_KEY"}, ""),
+		Hostname:        defaultEnv("TS_HOSTNAME", ""),
+		Routes:          defaultEnv("TS_ROUTES", ""),
+		ProxyTo:         defaultEnv("TS_DEST_IP", ""),
+		DaemonExtraArgs: defaultEnv("TS_TAILSCALED_EXTRA_ARGS", ""),
+		ExtraArgs:       defaultEnv("TS_EXTRA_ARGS", ""),
+		InKubernetes:    os.Getenv("KUBERNETES_SERVICE_HOST") != "",
+		UserspaceMode:   defaultBool("TS_USERSPACE", true),
+		StateDir:        defaultEnv("TS_STATE_DIR", ""),
+		AcceptDNS:       defaultBool("TS_ACCEPT_DNS", false),
+		KubeSecret:      defaultEnv("TS_KUBE_SECRET", "tailscale"),
+		SOCKSProxyAddr:  defaultEnv("TS_SOCKS5_SERVER", ""),
+		HTTPProxyAddr:   defaultEnv("TS_OUTBOUND_HTTP_PROXY_LISTEN", ""),
+		Socket:          defaultEnv("TS_SOCKET", "/tmp/tailscaled.sock"),
+		AuthOnce:        defaultBool("TS_AUTH_ONCE", false),
+		Root:            defaultEnv("TS_TEST_ONLY_ROOT", "/"),
+	}
+
+	if cfg.ProxyTo != "" && cfg.UserspaceMode {
+		log.Fatal("TS_DEST_IP is not supported with TS_USERSPACE")
+	}
+
+	if !cfg.UserspaceMode {
+		if err := ensureTunFile(cfg.Root); err != nil {
+			log.Fatalf("Unable to create tuntap device file: %v", err)
+		}
+		if cfg.ProxyTo != "" || cfg.Routes != "" {
+			if err := ensureIPForwarding(cfg.Root, cfg.ProxyTo, cfg.Routes); err != nil {
+				log.Printf("Failed to enable IP forwarding: %v", err)
+				log.Printf("To run tailscale as a proxy or router container, IP forwarding must be enabled.")
+				if cfg.InKubernetes {
+					log.Fatalf("You can either set the sysctls as a privileged initContainer, or run the tailscale container with privileged=true.")
+				} else {
+					log.Fatalf("You can fix this by running the container with privileged=true, or the equivalent in your container runtime that permits access to sysctls.")
+				}
+			}
+		}
+	}
+
+	if cfg.InKubernetes {
+		initKube(cfg.Root)
+	}
+
+	// Context is used for all setup stuff until we're in steady
+	// state, so that if something is hanging we eventually time out
+	// and crashloop the container.
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
+	defer cancel()
+
+	if cfg.InKubernetes && cfg.KubeSecret != "" {
+		canPatch, err := kc.CheckSecretPermissions(ctx, cfg.KubeSecret)
+		if err != nil {
+			log.Fatalf("Some Kubernetes permissions are missing, please check your RBAC configuration: %v", err)
+		}
+		cfg.KubernetesCanPatch = canPatch
+
+		if cfg.AuthKey == "" {
+			key, err := findKeyInKubeSecret(ctx, cfg.KubeSecret)
+			if err != nil {
+				log.Fatalf("Getting authkey from kube secret: %v", err)
+			}
+			if key != "" {
+				// This behavior of pulling authkeys from kube secrets was added
+				// at the same time as the patch permission, so we can enforce
+				// that we must be able to patch out the authkey after
+				// authenticating if you want to use this feature. This avoids
+				// us having to deal with the case where we might leave behind
+				// an unnecessary reusable authkey in a secret, like a rake in
+				// the grass.
+				if !cfg.KubernetesCanPatch {
+					log.Fatalf("authkey found in TS_KUBE_SECRET, but the pod doesn't have patch permissions on the secret to manage the authkey.")
+				}
+				log.Print("Using authkey found in kube secret")
+				cfg.AuthKey = key
+			} else {
+				log.Print("No authkey found in kube secret and TS_AUTHKEY not provided, login will be interactive if needed.")
+			}
+		}
+	}
+
+	client, daemonPid, err := startTailscaled(ctx, cfg)
+	if err != nil {
+		log.Fatalf("failed to bring up tailscale: %v", err)
+	}
+
+	w, err := client.WatchIPNBus(ctx, ipn.NotifyInitialNetMap|ipn.NotifyInitialPrefs|ipn.NotifyInitialState)
+	if err != nil {
+		log.Fatalf("failed to watch tailscaled for updates: %v", err)
+	}
+
+	// Because we're still shelling out to `tailscale up` to get access to its
+	// flag parser, we have to stop watching the IPN bus so that we can block on
+	// the subcommand without stalling anything. Then once it's done, we resume
+	// watching the bus.
+	//
+	// Depending on the requested mode of operation, this auth step happens at
+	// different points in containerboot's lifecycle, hence the helper function.
+	didLogin := false
+	authTailscale := func() error {
+		if didLogin {
+			return nil
+		}
+		didLogin = true
+		w.Close()
+		if err := tailscaleUp(ctx, cfg); err != nil {
+			return fmt.Errorf("failed to auth tailscale: %v", err)
+		}
+		w, err = client.WatchIPNBus(ctx, ipn.NotifyInitialNetMap|ipn.NotifyInitialState)
+		if err != nil {
+			return fmt.Errorf("rewatching tailscaled for updates after auth: %v", err)
+		}
+		return nil
+	}
+
+	if !cfg.AuthOnce {
+		if err := authTailscale(); err != nil {
+			log.Fatalf("failed to auth tailscale: %v", err)
+		}
+	}
+
+authLoop:
+	for {
+		n, err := w.Next()
+		if err != nil {
+			log.Fatalf("failed to read from tailscaled: %v", err)
+		}
+
+		if n.State != nil {
+			switch *n.State {
+			case ipn.NeedsLogin:
+				if err := authTailscale(); err != nil {
+					log.Fatalf("failed to auth tailscale: %v", err)
+				}
+			case ipn.NeedsMachineAuth:
+				log.Printf("machine authorization required, please visit the admin panel")
+			case ipn.Running:
+				// Technically, all we want is to keep monitoring the bus for
+				// netmap updates. However, in order to make the container crash
+				// if tailscale doesn't initially come up, the watch has a
+				// startup deadline on it. So, we have to break out of this
+				// watch loop, cancel the watch, and watch again with no
+				// deadline to continue monitoring for changes.
+				break authLoop
+			default:
+				log.Printf("tailscaled in state %q, waiting", *n.State)
+			}
+		}
+	}
+
+	w.Close()
+
+	if cfg.InKubernetes && cfg.KubeSecret != "" && cfg.KubernetesCanPatch && cfg.AuthOnce {
+		// We were told to only auth once, so any secret-bound
+		// authkey is no longer needed. We don't strictly need to
+		// wipe it, but it's good hygiene.
+		log.Printf("Deleting authkey from kube secret")
+		if err := deleteAuthKey(ctx, cfg.KubeSecret); err != nil {
+			log.Fatalf("deleting authkey from kube secret: %v", err)
+		}
+	}
+
+	w, err = client.WatchIPNBus(context.Background(), ipn.NotifyInitialNetMap|ipn.NotifyInitialState)
+	if err != nil {
+		log.Fatalf("rewatching tailscaled for updates after auth: %v", err)
+	}
+
+	var (
+		wantProxy         = cfg.ProxyTo != ""
+		wantDeviceInfo    = cfg.InKubernetes && cfg.KubeSecret != "" && cfg.KubernetesCanPatch
+		startupTasksDone  = false
+		currentIPs        deephash.Sum // tailscale IPs assigned to device
+		currentDeviceInfo deephash.Sum // device ID and fqdn
+	)
+	for {
+		n, err := w.Next()
+		if err != nil {
+			log.Fatalf("failed to read from tailscaled: %v", err)
+		}
+
+		if n.State != nil && *n.State != ipn.Running {
+			// Something's gone wrong and we've left the authenticated state.
+			// Our container image never recovered gracefully from this, and the
+			// control flow required to make it work now is hard. So, just crash
+			// the container and rely on the container runtime to restart us,
+			// whereupon we'll go through initial auth again.
+			log.Fatalf("tailscaled left running state (now in state %q), exiting", *n.State)
+		}
+		if n.NetMap != nil {
+			if cfg.ProxyTo != "" && len(n.NetMap.Addresses) > 0 && deephash.Update(&currentIPs, &n.NetMap.Addresses) {
+				if err := installIPTablesRule(ctx, cfg.ProxyTo, n.NetMap.Addresses); err != nil {
+					log.Fatalf("installing proxy rules: %v", err)
+				}
+			}
+			deviceInfo := []any{n.NetMap.SelfNode.StableID, n.NetMap.SelfNode.Name}
+			if cfg.InKubernetes && cfg.KubernetesCanPatch && cfg.KubeSecret != "" && deephash.Update(&currentDeviceInfo, &deviceInfo) {
+				if err := storeDeviceInfo(ctx, cfg.KubeSecret, n.NetMap.SelfNode.StableID, n.NetMap.SelfNode.Name); err != nil {
+					log.Fatalf("storing device ID in kube secret: %v", err)
+				}
+			}
+		}
+		if !startupTasksDone {
+			if (!wantProxy || currentIPs != deephash.Sum{}) && (!wantDeviceInfo || currentDeviceInfo != deephash.Sum{}) {
+				// This log message is used in tests to detect when all
+				// post-auth configuration is done.
+				log.Println("Startup complete, waiting for shutdown signal")
+				startupTasksDone = true
+
+				// Reap all processes, since we are PID1 and need to collect zombies. We can
+				// only start doing this once we've stopped shelling out to things
+				// `tailscale up`, otherwise this goroutine can reap the CLI subprocesses
+				// and wedge bringup.
+				go func() {
+					for {
+						var status unix.WaitStatus
+						pid, err := unix.Wait4(-1, &status, 0, nil)
+						if errors.Is(err, unix.EINTR) {
+							continue
+						}
+						if err != nil {
+							log.Fatalf("Waiting for exited processes: %v", err)
+						}
+						if pid == daemonPid {
+							log.Printf("Tailscaled exited")
+							os.Exit(0)
+						}
+					}
+				}()
+			}
+		}
+	}
+}
+
+func startTailscaled(ctx context.Context, cfg *settings) (*tailscale.LocalClient, int, error) {
+	args := tailscaledArgs(cfg)
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, unix.SIGTERM, unix.SIGINT)
+	// tailscaled runs without context, since it needs to persist
+	// beyond the startup timeout in ctx.
+	cmd := exec.Command("tailscaled", args...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Setpgid: true,
+	}
+	log.Printf("Starting tailscaled")
+	if err := cmd.Start(); err != nil {
+		return nil, 0, fmt.Errorf("starting tailscaled failed: %v", err)
+	}
+	go func() {
+		<-sigCh
+		log.Printf("Received SIGTERM from container runtime, shutting down tailscaled")
+		cmd.Process.Signal(unix.SIGTERM)
+	}()
+
+	// Wait for the socket file to appear, otherwise API ops will racily fail.
+	log.Printf("Waiting for tailscaled socket")
+	for {
+		if ctx.Err() != nil {
+			log.Fatalf("Timed out waiting for tailscaled socket")
+		}
+		_, err := os.Stat(cfg.Socket)
+		if errors.Is(err, fs.ErrNotExist) {
+			time.Sleep(100 * time.Millisecond)
+			continue
+		} else if err != nil {
+			log.Fatalf("Waiting for tailscaled socket: %v", err)
+		}
+		break
+	}
+
+	tsClient := &tailscale.LocalClient{
+		Socket:        cfg.Socket,
+		UseSocketOnly: true,
+	}
+
+	return tsClient, cmd.Process.Pid, nil
+}
+
+// tailscaledArgs uses cfg to construct the argv for tailscaled.
+func tailscaledArgs(cfg *settings) []string {
+	args := []string{"--socket=" + cfg.Socket}
+	switch {
+	case cfg.InKubernetes && cfg.KubeSecret != "":
+		args = append(args, "--state=kube:"+cfg.KubeSecret)
+		if cfg.StateDir == "" {
+			cfg.StateDir = "/tmp"
+		}
+		fallthrough
+	case cfg.StateDir != "":
+		args = append(args, "--statedir="+cfg.StateDir)
+	default:
+		args = append(args, "--state=mem:", "--statedir=/tmp")
+	}
+
+	if cfg.UserspaceMode {
+		args = append(args, "--tun=userspace-networking")
+	} else if err := ensureTunFile(cfg.Root); err != nil {
+		log.Fatalf("ensuring that /dev/net/tun exists: %v", err)
+	}
+
+	if cfg.SOCKSProxyAddr != "" {
+		args = append(args, "--socks5-server="+cfg.SOCKSProxyAddr)
+	}
+	if cfg.HTTPProxyAddr != "" {
+		args = append(args, "--outbound-http-proxy-listen="+cfg.HTTPProxyAddr)
+	}
+	if cfg.DaemonExtraArgs != "" {
+		args = append(args, strings.Fields(cfg.DaemonExtraArgs)...)
+	}
+	return args
+}
+
+// tailscaleUp uses cfg to run 'tailscale up'.
+func tailscaleUp(ctx context.Context, cfg *settings) error {
+	args := []string{"--socket=" + cfg.Socket, "up"}
+	if cfg.AcceptDNS {
+		args = append(args, "--accept-dns=true")
+	} else {
+		args = append(args, "--accept-dns=false")
+	}
+	if cfg.AuthKey != "" {
+		args = append(args, "--authkey="+cfg.AuthKey)
+	}
+	if cfg.Routes != "" {
+		args = append(args, "--advertise-routes="+cfg.Routes)
+	}
+	if cfg.Hostname != "" {
+		args = append(args, "--hostname="+cfg.Hostname)
+	}
+	if cfg.ExtraArgs != "" {
+		args = append(args, strings.Fields(cfg.ExtraArgs)...)
+	}
+	log.Printf("Running 'tailscale up'")
+	cmd := exec.CommandContext(ctx, "tailscale", args...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("tailscale up failed: %v", err)
+	}
+	return nil
+}
+
+// ensureTunFile checks that /dev/net/tun exists, creating it if
+// missing.
+func ensureTunFile(root string) error {
+	// Verify that /dev/net/tun exists, in some container envs it
+	// needs to be mknod-ed.
+	if _, err := os.Stat(filepath.Join(root, "dev/net")); errors.Is(err, fs.ErrNotExist) {
+		if err := os.MkdirAll(filepath.Join(root, "dev/net"), 0755); err != nil {
+			return err
+		}
+	}
+	if _, err := os.Stat(filepath.Join(root, "dev/net/tun")); errors.Is(err, fs.ErrNotExist) {
+		dev := unix.Mkdev(10, 200) // tuntap major and minor
+		if err := unix.Mknod(filepath.Join(root, "dev/net/tun"), 0600|unix.S_IFCHR, int(dev)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// ensureIPForwarding enables IPv4/IPv6 forwarding for the container.
+func ensureIPForwarding(root, proxyTo, routes string) error {
+	var (
+		v4Forwarding, v6Forwarding bool
+	)
+	if proxyTo != "" {
+		proxyIP, err := netip.ParseAddr(proxyTo)
+		if err != nil {
+			return fmt.Errorf("invalid proxy destination IP: %v", err)
+		}
+		if proxyIP.Is4() {
+			v4Forwarding = true
+		} else {
+			v6Forwarding = true
+		}
+	}
+	if routes != "" {
+		for _, route := range strings.Split(routes, ",") {
+			cidr, err := netip.ParsePrefix(route)
+			if err != nil {
+				return fmt.Errorf("invalid subnet route: %v", err)
+			}
+			if cidr.Addr().Is4() {
+				v4Forwarding = true
+			} else {
+				v6Forwarding = true
+			}
+		}
+	}
+
+	var paths []string
+	if v4Forwarding {
+		paths = append(paths, filepath.Join(root, "proc/sys/net/ipv4/ip_forward"))
+	}
+	if v6Forwarding {
+		paths = append(paths, filepath.Join(root, "proc/sys/net/ipv6/conf/all/forwarding"))
+	}
+
+	// In some common configurations (e.g. default docker,
+	// kubernetes), the container environment denies write access to
+	// most sysctls, including IP forwarding controls. Check the
+	// sysctl values before trying to change them, so that we
+	// gracefully do nothing if the container's already been set up
+	// properly by e.g. a k8s initContainer.
+	for _, path := range paths {
+		bs, err := os.ReadFile(path)
+		if err != nil {
+			return fmt.Errorf("reading %q: %w", path, err)
+		}
+		if v := strings.TrimSpace(string(bs)); v != "1" {
+			if err := os.WriteFile(path, []byte("1"), 0644); err != nil {
+				return fmt.Errorf("enabling %q: %w", path, err)
+			}
+		}
+	}
+	return nil
+}
+
+func installIPTablesRule(ctx context.Context, dstStr string, tsIPs []netip.Prefix) error {
+	dst, err := netip.ParseAddr(dstStr)
+	if err != nil {
+		return err
+	}
+	argv0 := "iptables"
+	if dst.Is6() {
+		argv0 = "ip6tables"
+	}
+	var local string
+	for _, pfx := range tsIPs {
+		if !pfx.IsSingleIP() {
+			continue
+		}
+		if pfx.Addr().Is4() != dst.Is4() {
+			continue
+		}
+		local = pfx.Addr().String()
+		break
+	}
+	if local == "" {
+		return fmt.Errorf("no tailscale IP matching family of %s found in %v", dstStr, tsIPs)
+	}
+	// Technically, if the control server ever changes the IPs assigned to this
+	// node, we'll slowly accumulate iptables rules. This shouldn't happen, so
+	// for now we'll live with it.
+	cmd := exec.CommandContext(ctx, argv0, "-t", "nat", "-I", "PREROUTING", "1", "-d", local, "-j", "DNAT", "--to-destination", dstStr)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("executing iptables failed: %w", err)
+	}
+	return nil
+}
+
+// settings is all the configuration for containerboot.
+type settings struct {
+	AuthKey            string
+	Hostname           string
+	Routes             string
+	ProxyTo            string
+	DaemonExtraArgs    string
+	ExtraArgs          string
+	InKubernetes       bool
+	UserspaceMode      bool
+	StateDir           string
+	AcceptDNS          bool
+	KubeSecret         string
+	SOCKSProxyAddr     string
+	HTTPProxyAddr      string
+	Socket             string
+	AuthOnce           bool
+	Root               string
+	KubernetesCanPatch bool
+}
+
+// defaultEnv returns the value of the given envvar name, or defVal if
+// unset.
+func defaultEnv(name, defVal string) string {
+	if v, ok := os.LookupEnv(name); ok {
+		return v
+	}
+	return defVal
+}
+
+func defaultEnvs(names []string, defVal string) string {
+	for _, name := range names {
+		if v, ok := os.LookupEnv(name); ok {
+			return v
+		}
+	}
+	return defVal
+}
+
+// defaultBool returns the boolean value of the given envvar name, or
+// defVal if unset or not a bool.
+func defaultBool(name string, defVal bool) bool {
+	v := os.Getenv(name)
+	ret, err := strconv.ParseBool(v)
+	if err != nil {
+		return defVal
+	}
+	return ret
+}

cmd/containerboot/test_tailscale.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+#
+# This is a fake tailscale CLI (and also iptables and ip6tables) that
+# records its arguments and exits successfully.
+#
+# It is used by main_test.go to test the behavior of containerboot.
+
+echo $0 $@ >>$TS_TEST_RECORD_ARGS

cmd/containerboot/test_tailscaled.sh

@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+#
+# This is a fake tailscale CLI that records its arguments, symlinks a
+# fake LocalAPI socket into place, and does nothing until terminated.
+#
+# It is used by main_test.go to test the behavior of containerboot.
+
+set -eu
+
+echo $0 $@ >>$TS_TEST_RECORD_ARGS
+
+socket=""
+while [[ $# -gt 0 ]]; do
+	case $1 in
+		--socket=*)
+			socket="${1#--socket=}"
+			shift
+			;;
+		--socket)
+			shift
+			socket="$1"
+			shift
+			;;
+		*)
+			shift
+			;;
+	esac
+done
+
+if [[ -z "$socket" ]]; then
+	echo "didn't find socket path in args"
+	exit 1
+fi
+
+ln -s "$TS_TEST_SOCKET" "$socket"
+
+while true; do sleep 1; done

cmd/derper/bootstrap_dns.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 package main
 
@@ -12,23 +11,37 @@ import (
 	"net"
 	"net/http"
 	"strings"
-	"sync"
 	"time"
+
+	"tailscale.com/syncs"
+	"tailscale.com/util/slicesx"
+)
+
+const refreshTimeout = time.Minute
+
+type dnsEntryMap map[string][]net.IP
+
+var (
+	dnsCache            syncs.AtomicValue[dnsEntryMap]
+	dnsCacheBytes       syncs.AtomicValue[[]byte] // of JSON
+	unpublishedDNSCache syncs.AtomicValue[dnsEntryMap]
 )
 
 var (
-	dnsMu    sync.Mutex
-	dnsCache = map[string][]net.IP{}
+	bootstrapDNSRequests = expvar.NewInt("counter_bootstrap_dns_requests")
+	publishedDNSHits     = expvar.NewInt("counter_bootstrap_dns_published_hits")
+	publishedDNSMisses   = expvar.NewInt("counter_bootstrap_dns_published_misses")
+	unpublishedDNSHits   = expvar.NewInt("counter_bootstrap_dns_unpublished_hits")
+	unpublishedDNSMisses = expvar.NewInt("counter_bootstrap_dns_unpublished_misses")
 )
 
-var bootstrapDNSRequests = expvar.NewInt("counter_bootstrap_dns_requests")
-
 func refreshBootstrapDNSLoop() {
-	if *bootstrapDNS == "" {
+	if *bootstrapDNS == "" && *unpublishedDNS == "" {
 		return
 	}
 	for {
 		refreshBootstrapDNS()
+		refreshUnpublishedDNS()
 		time.Sleep(10 * time.Minute)
 	}
 }
@@ -37,9 +50,41 @@ func refreshBootstrapDNS() {
 	if *bootstrapDNS == "" {
 		return
 	}
-	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+	ctx, cancel := context.WithTimeout(context.Background(), refreshTimeout)
 	defer cancel()
-	names := strings.Split(*bootstrapDNS, ",")
+	dnsEntries := resolveList(ctx, strings.Split(*bootstrapDNS, ","))
+	// Randomize the order of the IPs for each name to avoid the client biasing
+	// to IPv6
+	for k := range dnsEntries {
+		ips := dnsEntries[k]
+		slicesx.Shuffle(ips)
+		dnsEntries[k] = ips
+	}
+	j, err := json.MarshalIndent(dnsEntries, "", "\t")
+	if err != nil {
+		// leave the old values in place
+		return
+	}
+
+	dnsCache.Store(dnsEntries)
+	dnsCacheBytes.Store(j)
+}
+
+func refreshUnpublishedDNS() {
+	if *unpublishedDNS == "" {
+		return
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), refreshTimeout)
+	defer cancel()
+
+	dnsEntries := resolveList(ctx, strings.Split(*unpublishedDNS, ","))
+	unpublishedDNSCache.Store(dnsEntries)
+}
+
+func resolveList(ctx context.Context, names []string) dnsEntryMap {
+	dnsEntries := make(dnsEntryMap)
+
 	var r net.Resolver
 	for _, name := range names {
 		addrs, err := r.LookupIP(ctx, "ip", name)
@@ -47,23 +92,49 @@ func refreshBootstrapDNS() {
 			log.Printf("bootstrap DNS lookup %q: %v", name, err)
 			continue
 		}
-		dnsMu.Lock()
-		dnsCache[name] = addrs
-		dnsMu.Unlock()
+		dnsEntries[name] = addrs
 	}
+	return dnsEntries
 }
 
 func handleBootstrapDNS(w http.ResponseWriter, r *http.Request) {
 	bootstrapDNSRequests.Add(1)
-	dnsMu.Lock()
-	j, err := json.MarshalIndent(dnsCache, "", "\t")
-	dnsMu.Unlock()
-	if err != nil {
-		log.Printf("bootstrap DNS JSON: %v", err)
-		http.Error(w, "JSON marshal error", 500)
-		return
-	}
 
 	w.Header().Set("Content-Type", "application/json")
+	// Bootstrap DNS requests occur cross-regions, and are randomized per
+	// request, so keeping a connection open is pointlessly expensive.
+	w.Header().Set("Connection", "close")
+
+	// Try answering a query from our hidden map first
+	if q := r.URL.Query().Get("q"); q != "" {
+		if ips, ok := unpublishedDNSCache.Load()[q]; ok && len(ips) > 0 {
+			unpublishedDNSHits.Add(1)
+
+			// Only return the specific query, not everything.
+			m := dnsEntryMap{q: ips}
+			j, err := json.MarshalIndent(m, "", "\t")
+			if err == nil {
+				w.Write(j)
+				return
+			}
+		}
+
+		// If we have a "q" query for a name in the published cache
+		// list, then track whether that's a hit/miss.
+		if m, ok := dnsCache.Load()[q]; ok {
+			if len(m) > 0 {
+				publishedDNSHits.Add(1)
+			} else {
+				publishedDNSMisses.Add(1)
+			}
+		} else {
+			// If it wasn't in either cache, treat this as a query
+			// for the unpublished cache, and thus a cache miss.
+			unpublishedDNSMisses.Add(1)
+		}
+	}
+
+	// Fall back to returning the public set of cached DNS names
+	j := dnsCacheBytes.Load()
 	w.Write(j)
 }

cmd/derper/bootstrap_dns_test.go

@@ -0,0 +1,151 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"encoding/json"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"reflect"
+	"testing"
+
+	"tailscale.com/tstest"
+)
+
+func BenchmarkHandleBootstrapDNS(b *testing.B) {
+	tstest.Replace(b, bootstrapDNS, "log.tailscale.io,login.tailscale.com,controlplane.tailscale.com,login.us.tailscale.com")
+	refreshBootstrapDNS()
+	w := new(bitbucketResponseWriter)
+	req, _ := http.NewRequest("GET", "https://localhost/bootstrap-dns?q="+url.QueryEscape("log.tailscale.io"), nil)
+	b.ReportAllocs()
+	b.ResetTimer()
+	b.RunParallel(func(b *testing.PB) {
+		for b.Next() {
+			handleBootstrapDNS(w, req)
+		}
+	})
+}
+
+type bitbucketResponseWriter struct{}
+
+func (b *bitbucketResponseWriter) Header() http.Header { return make(http.Header) }
+
+func (b *bitbucketResponseWriter) Write(p []byte) (int, error) { return len(p), nil }
+
+func (b *bitbucketResponseWriter) WriteHeader(statusCode int) {}
+
+func getBootstrapDNS(t *testing.T, q string) dnsEntryMap {
+	t.Helper()
+	req, _ := http.NewRequest("GET", "https://localhost/bootstrap-dns?q="+url.QueryEscape(q), nil)
+	w := httptest.NewRecorder()
+	handleBootstrapDNS(w, req)
+
+	res := w.Result()
+	if res.StatusCode != 200 {
+		t.Fatalf("got status=%d; want %d", res.StatusCode, 200)
+	}
+	var ips dnsEntryMap
+	if err := json.NewDecoder(res.Body).Decode(&ips); err != nil {
+		t.Fatalf("error decoding response body: %v", err)
+	}
+	return ips
+}
+
+func TestUnpublishedDNS(t *testing.T) {
+	const published = "login.tailscale.com"
+	const unpublished = "log.tailscale.io"
+
+	prev1, prev2 := *bootstrapDNS, *unpublishedDNS
+	*bootstrapDNS = published
+	*unpublishedDNS = unpublished
+	t.Cleanup(func() {
+		*bootstrapDNS = prev1
+		*unpublishedDNS = prev2
+	})
+
+	refreshBootstrapDNS()
+	refreshUnpublishedDNS()
+
+	hasResponse := func(q string) bool {
+		_, found := getBootstrapDNS(t, q)[q]
+		return found
+	}
+
+	if !hasResponse(published) {
+		t.Errorf("expected response for: %s", published)
+	}
+	if !hasResponse(unpublished) {
+		t.Errorf("expected response for: %s", unpublished)
+	}
+
+	// Verify that querying for a random query or a real query does not
+	// leak our unpublished domain
+	m1 := getBootstrapDNS(t, published)
+	if _, found := m1[unpublished]; found {
+		t.Errorf("found unpublished domain %s: %+v", unpublished, m1)
+	}
+	m2 := getBootstrapDNS(t, "random.example.com")
+	if _, found := m2[unpublished]; found {
+		t.Errorf("found unpublished domain %s: %+v", unpublished, m2)
+	}
+}
+
+func resetMetrics() {
+	publishedDNSHits.Set(0)
+	publishedDNSMisses.Set(0)
+	unpublishedDNSHits.Set(0)
+	unpublishedDNSMisses.Set(0)
+}
+
+// Verify that we don't count an empty list in the unpublishedDNSCache as a
+// cache hit in our metrics.
+func TestUnpublishedDNSEmptyList(t *testing.T) {
+	pub := dnsEntryMap{
+		"tailscale.com": {net.IPv4(10, 10, 10, 10)},
+	}
+	dnsCache.Store(pub)
+	dnsCacheBytes.Store([]byte(`{"tailscale.com":["10.10.10.10"]}`))
+
+	unpublishedDNSCache.Store(dnsEntryMap{
+		"log.tailscale.io":           {},
+		"controlplane.tailscale.com": {net.IPv4(1, 2, 3, 4)},
+	})
+
+	t.Run("CacheMiss", func(t *testing.T) {
+		// One domain in map but empty, one not in map at all
+		for _, q := range []string{"log.tailscale.io", "login.tailscale.com"} {
+			resetMetrics()
+			ips := getBootstrapDNS(t, q)
+
+			// Expected our public map to be returned on a cache miss
+			if !reflect.DeepEqual(ips, pub) {
+				t.Errorf("got ips=%+v; want %+v", ips, pub)
+			}
+			if v := unpublishedDNSHits.Value(); v != 0 {
+				t.Errorf("got hits=%d; want 0", v)
+			}
+			if v := unpublishedDNSMisses.Value(); v != 1 {
+				t.Errorf("got misses=%d; want 1", v)
+			}
+		}
+	})
+
+	// Verify that we do get a valid response and metric.
+	t.Run("CacheHit", func(t *testing.T) {
+		resetMetrics()
+		ips := getBootstrapDNS(t, "controlplane.tailscale.com")
+		want := dnsEntryMap{"controlplane.tailscale.com": {net.IPv4(1, 2, 3, 4)}}
+		if !reflect.DeepEqual(ips, want) {
+			t.Errorf("got ips=%+v; want %+v", ips, want)
+		}
+		if v := unpublishedDNSHits.Value(); v != 1 {
+			t.Errorf("got hits=%d; want 1", v)
+		}
+		if v := unpublishedDNSMisses.Value(); v != 0 {
+			t.Errorf("got misses=%d; want 0", v)
+		}
+	})
+}

cmd/derper/cert.go

@@ -0,0 +1,105 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"net/http"
+	"path/filepath"
+	"regexp"
+
+	"golang.org/x/crypto/acme/autocert"
+)
+
+var unsafeHostnameCharacters = regexp.MustCompile(`[^a-zA-Z0-9-\.]`)
+
+type certProvider interface {
+	// TLSConfig creates a new TLS config suitable for net/http.Server servers.
+	//
+	// The returned Config must have a GetCertificate function set and that
+	// function must return a unique *tls.Certificate for each call. The
+	// returned *tls.Certificate will be mutated by the caller to append to the
+	// (*tls.Certificate).Certificate field.
+	TLSConfig() *tls.Config
+	// HTTPHandler handle ACME related request, if any.
+	HTTPHandler(fallback http.Handler) http.Handler
+}
+
+func certProviderByCertMode(mode, dir, hostname string) (certProvider, error) {
+	if dir == "" {
+		return nil, errors.New("missing required --certdir flag")
+	}
+	switch mode {
+	case "letsencrypt":
+		certManager := &autocert.Manager{
+			Prompt:     autocert.AcceptTOS,
+			HostPolicy: autocert.HostWhitelist(hostname),
+			Cache:      autocert.DirCache(dir),
+		}
+		if hostname == "derp.tailscale.com" {
+			certManager.HostPolicy = prodAutocertHostPolicy
+			certManager.Email = "security@tailscale.com"
+		}
+		return certManager, nil
+	case "manual":
+		return NewManualCertManager(dir, hostname)
+	default:
+		return nil, fmt.Errorf("unsupport cert mode: %q", mode)
+	}
+}
+
+type manualCertManager struct {
+	cert     *tls.Certificate
+	hostname string
+}
+
+// NewManualCertManager returns a cert provider which read certificate by given hostname on create.
+func NewManualCertManager(certdir, hostname string) (certProvider, error) {
+	keyname := unsafeHostnameCharacters.ReplaceAllString(hostname, "")
+	crtPath := filepath.Join(certdir, keyname+".crt")
+	keyPath := filepath.Join(certdir, keyname+".key")
+	cert, err := tls.LoadX509KeyPair(crtPath, keyPath)
+	if err != nil {
+		return nil, fmt.Errorf("can not load x509 key pair for hostname %q: %w", keyname, err)
+	}
+	// ensure hostname matches with the certificate
+	x509Cert, err := x509.ParseCertificate(cert.Certificate[0])
+	if err != nil {
+		return nil, fmt.Errorf("can not load cert: %w", err)
+	}
+	if err := x509Cert.VerifyHostname(hostname); err != nil {
+		return nil, fmt.Errorf("cert invalid for hostname %q: %w", hostname, err)
+	}
+	return &manualCertManager{cert: &cert, hostname: hostname}, nil
+}
+
+func (m *manualCertManager) TLSConfig() *tls.Config {
+	return &tls.Config{
+		Certificates: nil,
+		NextProtos: []string{
+			"http/1.1",
+		},
+		GetCertificate: m.getCertificate,
+	}
+}
+
+func (m *manualCertManager) getCertificate(hi *tls.ClientHelloInfo) (*tls.Certificate, error) {
+	if hi.ServerName != m.hostname {
+		return nil, fmt.Errorf("cert mismatch with hostname: %q", hi.ServerName)
+	}
+
+	// Return a shallow copy of the cert so the caller can append to its
+	// Certificate field.
+	certCopy := new(tls.Certificate)
+	*certCopy = *m.cert
+	certCopy.Certificate = certCopy.Certificate[:len(certCopy.Certificate):len(certCopy.Certificate)]
+	return certCopy, nil
+}
+
+func (m *manualCertManager) HTTPHandler(fallback http.Handler) http.Handler {
+	return fallback
+}

cmd/derper/depaware.txt

@@ -0,0 +1,281 @@
+tailscale.com/cmd/derper dependencies: (generated by github.com/tailscale/depaware)
+
+        filippo.io/edwards25519                                      from github.com/hdevalence/ed25519consensus
+        filippo.io/edwards25519/field                                from filippo.io/edwards25519
+   W 💣 github.com/Microsoft/go-winio                                from tailscale.com/safesocket
+   W 💣 github.com/Microsoft/go-winio/internal/fs                    from github.com/Microsoft/go-winio
+   W 💣 github.com/Microsoft/go-winio/internal/socket                from github.com/Microsoft/go-winio
+   W    github.com/Microsoft/go-winio/internal/stringbuffer          from github.com/Microsoft/go-winio/internal/fs
+   W    github.com/Microsoft/go-winio/pkg/guid                       from github.com/Microsoft/go-winio+
+   W 💣 github.com/alexbrainman/sspi                                 from github.com/alexbrainman/sspi/internal/common+
+   W    github.com/alexbrainman/sspi/internal/common                 from github.com/alexbrainman/sspi/negotiate
+   W 💣 github.com/alexbrainman/sspi/negotiate                       from tailscale.com/net/tshttpproxy
+        github.com/beorn7/perks/quantile                             from github.com/prometheus/client_golang/prometheus
+     💣 github.com/cespare/xxhash/v2                                 from github.com/prometheus/client_golang/prometheus
+   L    github.com/coreos/go-iptables/iptables                       from tailscale.com/util/linuxfw
+        github.com/fxamacker/cbor/v2                                 from tailscale.com/tka
+        github.com/golang/groupcache/lru                             from tailscale.com/net/dnscache
+        github.com/golang/protobuf/proto                             from github.com/matttproud/golang_protobuf_extensions/pbutil+
+   L    github.com/google/nftables                                   from tailscale.com/util/linuxfw
+   L 💣 github.com/google/nftables/alignedbuff                       from github.com/google/nftables/xt
+   L 💣 github.com/google/nftables/binaryutil                        from github.com/google/nftables+
+   L    github.com/google/nftables/expr                              from github.com/google/nftables+
+   L    github.com/google/nftables/internal/parseexprfunc            from github.com/google/nftables+
+   L    github.com/google/nftables/xt                                from github.com/google/nftables/expr+
+        github.com/hdevalence/ed25519consensus                       from tailscale.com/tka
+   L    github.com/josharian/native                                  from github.com/mdlayher/netlink+
+   L 💣 github.com/jsimonetti/rtnetlink                              from tailscale.com/net/interfaces+
+   L    github.com/jsimonetti/rtnetlink/internal/unix                from github.com/jsimonetti/rtnetlink
+        github.com/klauspost/compress/flate                          from nhooyr.io/websocket
+        github.com/matttproud/golang_protobuf_extensions/pbutil      from github.com/prometheus/common/expfmt
+   L 💣 github.com/mdlayher/netlink                                  from github.com/jsimonetti/rtnetlink+
+   L 💣 github.com/mdlayher/netlink/nlenc                            from github.com/jsimonetti/rtnetlink+
+   L    github.com/mdlayher/netlink/nltest                           from github.com/google/nftables
+   L 💣 github.com/mdlayher/socket                                   from github.com/mdlayher/netlink
+     💣 github.com/mitchellh/go-ps                                   from tailscale.com/safesocket
+     💣 github.com/prometheus/client_golang/prometheus               from tailscale.com/tsweb/promvarz
+        github.com/prometheus/client_golang/prometheus/internal      from github.com/prometheus/client_golang/prometheus
+        github.com/prometheus/client_model/go                        from github.com/prometheus/client_golang/prometheus+
+        github.com/prometheus/common/expfmt                          from github.com/prometheus/client_golang/prometheus+
+        github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg from github.com/prometheus/common/expfmt
+        github.com/prometheus/common/model                           from github.com/prometheus/client_golang/prometheus+
+  LD    github.com/prometheus/procfs                                 from github.com/prometheus/client_golang/prometheus
+  LD    github.com/prometheus/procfs/internal/fs                     from github.com/prometheus/procfs
+  LD    github.com/prometheus/procfs/internal/util                   from github.com/prometheus/procfs
+   L 💣 github.com/tailscale/netlink                                 from tailscale.com/util/linuxfw
+   L 💣 github.com/vishvananda/netlink/nl                            from github.com/tailscale/netlink
+   L    github.com/vishvananda/netns                                 from github.com/tailscale/netlink+
+        github.com/x448/float16                                      from github.com/fxamacker/cbor/v2
+     💣 go4.org/mem                                                  from tailscale.com/client/tailscale+
+        go4.org/netipx                                               from tailscale.com/wgengine/filter
+   W 💣 golang.zx2c4.com/wireguard/windows/tunnel/winipcfg           from tailscale.com/net/interfaces+
+        google.golang.org/protobuf/encoding/prototext                from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/encoding/protowire                from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/internal/descfmt                  from google.golang.org/protobuf/internal/filedesc
+        google.golang.org/protobuf/internal/descopts                 from google.golang.org/protobuf/internal/filedesc+
+        google.golang.org/protobuf/internal/detrand                  from google.golang.org/protobuf/internal/descfmt+
+        google.golang.org/protobuf/internal/encoding/defval          from google.golang.org/protobuf/internal/encoding/tag+
+        google.golang.org/protobuf/internal/encoding/messageset      from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/encoding/tag             from google.golang.org/protobuf/internal/impl
+        google.golang.org/protobuf/internal/encoding/text            from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/errors                   from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/filedesc                 from google.golang.org/protobuf/internal/encoding/tag+
+        google.golang.org/protobuf/internal/filetype                 from google.golang.org/protobuf/runtime/protoimpl
+        google.golang.org/protobuf/internal/flags                    from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/genid                    from google.golang.org/protobuf/encoding/prototext+
+     💣 google.golang.org/protobuf/internal/impl                     from google.golang.org/protobuf/internal/filetype+
+        google.golang.org/protobuf/internal/order                    from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/pragma                   from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/set                      from google.golang.org/protobuf/encoding/prototext
+     💣 google.golang.org/protobuf/internal/strs                     from google.golang.org/protobuf/encoding/prototext+
+        google.golang.org/protobuf/internal/version                  from google.golang.org/protobuf/runtime/protoimpl
+        google.golang.org/protobuf/proto                             from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/reflect/protodesc                 from github.com/golang/protobuf/proto
+     💣 google.golang.org/protobuf/reflect/protoreflect              from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/reflect/protoregistry             from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/runtime/protoiface                from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/runtime/protoimpl                 from github.com/golang/protobuf/proto+
+        google.golang.org/protobuf/types/descriptorpb                from google.golang.org/protobuf/reflect/protodesc
+        google.golang.org/protobuf/types/known/timestamppb           from github.com/prometheus/client_golang/prometheus+
+        nhooyr.io/websocket                                          from tailscale.com/cmd/derper+
+        nhooyr.io/websocket/internal/errd                            from nhooyr.io/websocket
+        nhooyr.io/websocket/internal/xsync                           from nhooyr.io/websocket
+        tailscale.com                                                from tailscale.com/version
+        tailscale.com/atomicfile                                     from tailscale.com/cmd/derper+
+        tailscale.com/client/tailscale                               from tailscale.com/derp
+        tailscale.com/client/tailscale/apitype                       from tailscale.com/client/tailscale
+        tailscale.com/derp                                           from tailscale.com/cmd/derper+
+        tailscale.com/derp/derphttp                                  from tailscale.com/cmd/derper
+        tailscale.com/disco                                          from tailscale.com/derp
+        tailscale.com/envknob                                        from tailscale.com/derp+
+        tailscale.com/health                                         from tailscale.com/net/tlsdial
+        tailscale.com/hostinfo                                       from tailscale.com/net/interfaces+
+        tailscale.com/ipn                                            from tailscale.com/client/tailscale
+        tailscale.com/ipn/ipnstate                                   from tailscale.com/client/tailscale+
+        tailscale.com/metrics                                        from tailscale.com/cmd/derper+
+        tailscale.com/net/dnscache                                   from tailscale.com/derp/derphttp
+        tailscale.com/net/flowtrack                                  from tailscale.com/net/packet+
+     💣 tailscale.com/net/interfaces                                 from tailscale.com/net/netns+
+        tailscale.com/net/netaddr                                    from tailscale.com/ipn+
+        tailscale.com/net/netknob                                    from tailscale.com/net/netns
+        tailscale.com/net/netmon                                     from tailscale.com/net/sockstats+
+        tailscale.com/net/netns                                      from tailscale.com/derp/derphttp
+        tailscale.com/net/netutil                                    from tailscale.com/client/tailscale
+        tailscale.com/net/packet                                     from tailscale.com/wgengine/filter
+        tailscale.com/net/sockstats                                  from tailscale.com/derp/derphttp
+        tailscale.com/net/stun                                       from tailscale.com/cmd/derper
+   L    tailscale.com/net/tcpinfo                                    from tailscale.com/derp
+        tailscale.com/net/tlsdial                                    from tailscale.com/derp/derphttp
+        tailscale.com/net/tsaddr                                     from tailscale.com/ipn+
+     💣 tailscale.com/net/tshttpproxy                                from tailscale.com/derp/derphttp+
+        tailscale.com/net/wsconn                                     from tailscale.com/cmd/derper+
+        tailscale.com/paths                                          from tailscale.com/client/tailscale
+        tailscale.com/safesocket                                     from tailscale.com/client/tailscale
+        tailscale.com/syncs                                          from tailscale.com/cmd/derper+
+        tailscale.com/tailcfg                                        from tailscale.com/client/tailscale+
+        tailscale.com/tka                                            from tailscale.com/client/tailscale+
+   W    tailscale.com/tsconst                                        from tailscale.com/net/interfaces
+     💣 tailscale.com/tstime/mono                                    from tailscale.com/tstime/rate
+        tailscale.com/tstime/rate                                    from tailscale.com/wgengine/filter+
+        tailscale.com/tsweb                                          from tailscale.com/cmd/derper
+        tailscale.com/tsweb/promvarz                                 from tailscale.com/tsweb
+        tailscale.com/tsweb/varz                                     from tailscale.com/tsweb+
+        tailscale.com/types/dnstype                                  from tailscale.com/tailcfg
+        tailscale.com/types/empty                                    from tailscale.com/ipn
+        tailscale.com/types/ipproto                                  from tailscale.com/net/flowtrack+
+        tailscale.com/types/key                                      from tailscale.com/cmd/derper+
+        tailscale.com/types/lazy                                     from tailscale.com/version+
+        tailscale.com/types/logger                                   from tailscale.com/cmd/derper+
+        tailscale.com/types/netmap                                   from tailscale.com/ipn
+        tailscale.com/types/opt                                      from tailscale.com/client/tailscale+
+        tailscale.com/types/persist                                  from tailscale.com/ipn
+        tailscale.com/types/preftype                                 from tailscale.com/ipn
+        tailscale.com/types/ptr                                      from tailscale.com/hostinfo+
+        tailscale.com/types/structs                                  from tailscale.com/ipn+
+        tailscale.com/types/tkatype                                  from tailscale.com/types/key+
+        tailscale.com/types/views                                    from tailscale.com/ipn/ipnstate+
+   W    tailscale.com/util/clientmetric                              from tailscale.com/net/tshttpproxy
+        tailscale.com/util/cloudenv                                  from tailscale.com/hostinfo+
+   W    tailscale.com/util/cmpver                                    from tailscale.com/net/tshttpproxy
+        tailscale.com/util/cmpx                                      from tailscale.com/cmd/derper+
+   L 💣 tailscale.com/util/dirwalk                                   from tailscale.com/metrics
+        tailscale.com/util/dnsname                                   from tailscale.com/hostinfo+
+        tailscale.com/util/httpm                                     from tailscale.com/client/tailscale
+        tailscale.com/util/lineread                                  from tailscale.com/hostinfo+
+   L    tailscale.com/util/linuxfw                                   from tailscale.com/net/netns
+        tailscale.com/util/mak                                       from tailscale.com/syncs+
+        tailscale.com/util/multierr                                  from tailscale.com/health+
+        tailscale.com/util/set                                       from tailscale.com/health+
+        tailscale.com/util/singleflight                              from tailscale.com/net/dnscache
+        tailscale.com/util/slicesx                                   from tailscale.com/cmd/derper+
+        tailscale.com/util/vizerror                                  from tailscale.com/tsweb
+   W 💣 tailscale.com/util/winutil                                   from tailscale.com/hostinfo+
+        tailscale.com/version                                        from tailscale.com/derp+
+        tailscale.com/version/distro                                 from tailscale.com/hostinfo+
+        tailscale.com/wgengine/filter                                from tailscale.com/types/netmap
+        golang.org/x/crypto/acme                                     from golang.org/x/crypto/acme/autocert
+        golang.org/x/crypto/acme/autocert                            from tailscale.com/cmd/derper
+        golang.org/x/crypto/argon2                                   from tailscale.com/tka
+        golang.org/x/crypto/blake2b                                  from golang.org/x/crypto/nacl/box+
+        golang.org/x/crypto/blake2s                                  from tailscale.com/tka
+        golang.org/x/crypto/chacha20                                 from golang.org/x/crypto/chacha20poly1305
+        golang.org/x/crypto/chacha20poly1305                         from crypto/tls
+        golang.org/x/crypto/cryptobyte                               from crypto/ecdsa+
+        golang.org/x/crypto/cryptobyte/asn1                          from crypto/ecdsa+
+        golang.org/x/crypto/curve25519                               from golang.org/x/crypto/nacl/box+
+        golang.org/x/crypto/hkdf                                     from crypto/tls
+        golang.org/x/crypto/nacl/box                                 from tailscale.com/types/key
+        golang.org/x/crypto/nacl/secretbox                           from golang.org/x/crypto/nacl/box
+        golang.org/x/crypto/salsa20/salsa                            from golang.org/x/crypto/nacl/box+
+        golang.org/x/exp/constraints                                 from golang.org/x/exp/slices
+        golang.org/x/exp/maps                                        from tailscale.com/types/views
+        golang.org/x/exp/slices                                      from tailscale.com/net/tsaddr+
+   L    golang.org/x/net/bpf                                         from github.com/mdlayher/netlink+
+        golang.org/x/net/dns/dnsmessage                              from net+
+        golang.org/x/net/http/httpguts                               from net/http
+        golang.org/x/net/http/httpproxy                              from net/http+
+        golang.org/x/net/http2/hpack                                 from net/http
+        golang.org/x/net/idna                                        from golang.org/x/crypto/acme/autocert+
+        golang.org/x/net/proxy                                       from tailscale.com/net/netns
+   D    golang.org/x/net/route                                       from net+
+        golang.org/x/sync/errgroup                                   from github.com/mdlayher/socket+
+        golang.org/x/sys/cpu                                         from golang.org/x/crypto/blake2b+
+  LD    golang.org/x/sys/unix                                        from github.com/jsimonetti/rtnetlink/internal/unix+
+   W    golang.org/x/sys/windows                                     from golang.org/x/sys/windows/registry+
+   W    golang.org/x/sys/windows/registry                            from golang.zx2c4.com/wireguard/windows/tunnel/winipcfg+
+   W    golang.org/x/sys/windows/svc                                 from golang.org/x/sys/windows/svc/mgr+
+   W    golang.org/x/sys/windows/svc/mgr                             from tailscale.com/util/winutil
+        golang.org/x/text/secure/bidirule                            from golang.org/x/net/idna
+        golang.org/x/text/transform                                  from golang.org/x/text/secure/bidirule+
+        golang.org/x/text/unicode/bidi                               from golang.org/x/net/idna+
+        golang.org/x/text/unicode/norm                               from golang.org/x/net/idna
+        golang.org/x/time/rate                                       from tailscale.com/cmd/derper+
+        bufio                                                        from compress/flate+
+        bytes                                                        from bufio+
+        compress/flate                                               from compress/gzip+
+        compress/gzip                                                from internal/profile+
+        container/list                                               from crypto/tls+
+        context                                                      from crypto/tls+
+        crypto                                                       from crypto/ecdsa+
+        crypto/aes                                                   from crypto/ecdsa+
+        crypto/cipher                                                from crypto/aes+
+        crypto/des                                                   from crypto/tls+
+        crypto/dsa                                                   from crypto/x509
+        crypto/ecdh                                                  from crypto/ecdsa+
+        crypto/ecdsa                                                 from crypto/tls+
+        crypto/ed25519                                               from crypto/tls+
+        crypto/elliptic                                              from crypto/ecdsa+
+        crypto/hmac                                                  from crypto/tls+
+        crypto/md5                                                   from crypto/tls+
+        crypto/rand                                                  from crypto/ed25519+
+        crypto/rc4                                                   from crypto/tls
+        crypto/rsa                                                   from crypto/tls+
+        crypto/sha1                                                  from crypto/tls+
+        crypto/sha256                                                from crypto/tls+
+        crypto/sha512                                                from crypto/ecdsa+
+        crypto/subtle                                                from crypto/aes+
+        crypto/tls                                                   from golang.org/x/crypto/acme+
+        crypto/x509                                                  from crypto/tls+
+        crypto/x509/pkix                                             from crypto/x509+
+        embed                                                        from crypto/internal/nistec+
+        encoding                                                     from encoding/json+
+        encoding/asn1                                                from crypto/x509+
+        encoding/base32                                              from tailscale.com/tka
+        encoding/base64                                              from encoding/json+
+        encoding/binary                                              from compress/gzip+
+        encoding/hex                                                 from crypto/x509+
+        encoding/json                                                from expvar+
+        encoding/pem                                                 from crypto/tls+
+        errors                                                       from bufio+
+        expvar                                                       from tailscale.com/cmd/derper+
+        flag                                                         from tailscale.com/cmd/derper
+        fmt                                                          from compress/flate+
+        go/token                                                     from google.golang.org/protobuf/internal/strs
+        hash                                                         from crypto+
+        hash/crc32                                                   from compress/gzip+
+        hash/fnv                                                     from google.golang.org/protobuf/internal/detrand
+        hash/maphash                                                 from go4.org/mem
+        html                                                         from net/http/pprof+
+        io                                                           from bufio+
+        io/fs                                                        from crypto/x509+
+        io/ioutil                                                    from github.com/mitchellh/go-ps+
+        log                                                          from expvar+
+        log/internal                                                 from log
+        math                                                         from compress/flate+
+        math/big                                                     from crypto/dsa+
+        math/bits                                                    from compress/flate+
+        math/rand                                                    from github.com/mdlayher/netlink+
+        mime                                                         from mime/multipart+
+        mime/multipart                                               from net/http
+        mime/quotedprintable                                         from mime/multipart
+        net                                                          from crypto/tls+
+        net/http                                                     from expvar+
+        net/http/httptrace                                           from net/http+
+        net/http/internal                                            from net/http
+        net/http/pprof                                               from tailscale.com/tsweb+
+        net/netip                                                    from go4.org/netipx+
+        net/textproto                                                from golang.org/x/net/http/httpguts+
+        net/url                                                      from crypto/x509+
+        os                                                           from crypto/rand+
+        os/exec                                                      from golang.zx2c4.com/wireguard/windows/tunnel/winipcfg+
+   W    os/user                                                      from tailscale.com/util/winutil
+        path                                                         from golang.org/x/crypto/acme/autocert+
+        path/filepath                                                from crypto/x509+
+        reflect                                                      from crypto/x509+
+        regexp                                                       from internal/profile+
+        regexp/syntax                                                from regexp
+        runtime/debug                                                from golang.org/x/crypto/acme+
+        runtime/metrics                                              from github.com/prometheus/client_golang/prometheus+
+        runtime/pprof                                                from net/http/pprof
+        runtime/trace                                                from net/http/pprof
+        sort                                                         from compress/flate+
+        strconv                                                      from compress/flate+
+        strings                                                      from bufio+
+        sync                                                         from compress/flate+
+        sync/atomic                                                  from context+
+        syscall                                                      from crypto/rand+
+        text/tabwriter                                               from runtime/pprof
+        time                                                         from compress/gzip+
+        unicode                                                      from bytes+
+        unicode/utf16                                                from crypto/x509+
+        unicode/utf8                                                 from bufio+

cmd/derper/derper.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // The derper binary is a simple DERP server.
 package main // import "tailscale.com/cmd/derper"
@@ -12,50 +11,84 @@ import (
 	"errors"
 	"expvar"
 	"flag"
+	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
+	"math"
 	"net"
 	"net/http"
+	"net/netip"
 	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
 	"time"
 
-	"golang.org/x/crypto/acme/autocert"
+	"go4.org/mem"
+	"golang.org/x/time/rate"
 	"tailscale.com/atomicfile"
 	"tailscale.com/derp"
 	"tailscale.com/derp/derphttp"
-	"tailscale.com/logpolicy"
 	"tailscale.com/metrics"
 	"tailscale.com/net/stun"
 	"tailscale.com/tsweb"
 	"tailscale.com/types/key"
-	"tailscale.com/types/wgkey"
+	"tailscale.com/util/cmpx"
 )
 
 var (
-	dev           = flag.Bool("dev", false, "run in localhost development mode")
-	addr          = flag.String("a", ":443", "server address")
-	configPath    = flag.String("c", "", "config file path")
-	certDir       = flag.String("certdir", tsweb.DefaultCertDir("derper-certs"), "directory to store LetsEncrypt certs, if addr's port is :443")
-	hostname      = flag.String("hostname", "derp.tailscale.com", "LetsEncrypt host name, if addr's port is :443")
-	logCollection = flag.String("logcollection", "", "If non-empty, logtail collection to log to")
-	runSTUN       = flag.Bool("stun", false, "also run a STUN server")
-	meshPSKFile   = flag.String("mesh-psk-file", defaultMeshPSKFile(), "if non-empty, path to file containing the mesh pre-shared key file. It should contain some hex string; whitespace is trimmed.")
-	meshWith      = flag.String("mesh-with", "", "optional comma-separated list of hostnames to mesh with; the server's own hostname can be in the list")
-	bootstrapDNS  = flag.String("bootstrap-dns-names", "", "optional comma-separated list of hostnames to make available at /bootstrap-dns")
-	verifyClients = flag.Bool("verify-clients", false, "verify clients to this DERP server through a local tailscaled instance.")
+	dev        = flag.Bool("dev", false, "run in localhost development mode (overrides -a)")
+	addr       = flag.String("a", ":443", "server HTTP/HTTPS listen address, in form \":port\", \"ip:port\", or for IPv6 \"[ip]:port\". If the IP is omitted, it defaults to all interfaces. Serves HTTPS if the port is 443 and/or -certmode is manual, otherwise HTTP.")
+	httpPort   = flag.Int("http-port", 80, "The port on which to serve HTTP. Set to -1 to disable. The listener is bound to the same IP (if any) as specified in the -a flag.")
+	stunPort   = flag.Int("stun-port", 3478, "The UDP port on which to serve STUN. The listener is bound to the same IP (if any) as specified in the -a flag.")
+	configPath = flag.String("c", "", "config file path")
+	certMode   = flag.String("certmode", "letsencrypt", "mode for getting a cert. possible options: manual, letsencrypt")
+	certDir    = flag.String("certdir", tsweb.DefaultCertDir("derper-certs"), "directory to store LetsEncrypt certs, if addr's port is :443")
+	hostname   = flag.String("hostname", "derp.tailscale.com", "LetsEncrypt host name, if addr's port is :443")
+	runSTUN    = flag.Bool("stun", true, "whether to run a STUN server. It will bind to the same IP (if any) as the --addr flag value.")
+	runDERP    = flag.Bool("derp", true, "whether to run a DERP server. The only reason to set this false is if you're decommissioning a server but want to keep its bootstrap DNS functionality still running.")
+
+	meshPSKFile    = flag.String("mesh-psk-file", defaultMeshPSKFile(), "if non-empty, path to file containing the mesh pre-shared key file. It should contain some hex string; whitespace is trimmed.")
+	meshWith       = flag.String("mesh-with", "", "optional comma-separated list of hostnames to mesh with; the server's own hostname can be in the list")
+	bootstrapDNS   = flag.String("bootstrap-dns-names", "", "optional comma-separated list of hostnames to make available at /bootstrap-dns")
+	unpublishedDNS = flag.String("unpublished-bootstrap-dns-names", "", "optional comma-separated list of hostnames to make available at /bootstrap-dns and not publish in the list")
+	verifyClients  = flag.Bool("verify-clients", false, "verify clients to this DERP server through a local tailscaled instance.")
+
+	acceptConnLimit = flag.Float64("accept-connection-limit", math.Inf(+1), "rate limit for accepting new connection")
+	acceptConnBurst = flag.Int("accept-connection-burst", math.MaxInt, "burst limit for accepting new connection")
 )
 
+var (
+	stats             = new(metrics.Set)
+	stunDisposition   = &metrics.LabelMap{Label: "disposition"}
+	stunAddrFamily    = &metrics.LabelMap{Label: "family"}
+	tlsRequestVersion = &metrics.LabelMap{Label: "version"}
+	tlsActiveVersion  = &metrics.LabelMap{Label: "version"}
+
+	stunReadError  = stunDisposition.Get("read_error")
+	stunNotSTUN    = stunDisposition.Get("not_stun")
+	stunWriteError = stunDisposition.Get("write_error")
+	stunSuccess    = stunDisposition.Get("success")
+
+	stunIPv4 = stunAddrFamily.Get("ipv4")
+	stunIPv6 = stunAddrFamily.Get("ipv6")
+)
+
+func init() {
+	stats.Set("counter_requests", stunDisposition)
+	stats.Set("counter_addrfamily", stunAddrFamily)
+	expvar.Publish("stun", stats)
+	expvar.Publish("derper_tls_request_version", tlsRequestVersion)
+	expvar.Publish("gauge_derper_tls_active_version", tlsActiveVersion)
+}
+
 type config struct {
-	PrivateKey wgkey.Private
+	PrivateKey key.NodePrivate
 }
 
 func loadConfig() config {
 	if *dev {
-		return config{PrivateKey: mustNewKey()}
+		return config{PrivateKey: key.NewNode()}
 	}
 	if *configPath == "" {
 		if os.Getuid() == 0 {
@@ -65,7 +98,7 @@ func loadConfig() config {
 		}
 		log.Printf("no config path specified; using %s", *configPath)
 	}
-	b, err := ioutil.ReadFile(*configPath)
+	b, err := os.ReadFile(*configPath)
 	switch {
 	case errors.Is(err, os.ErrNotExist):
 		return writeNewConfig()
@@ -81,21 +114,13 @@ func loadConfig() config {
 	}
 }
 
-func mustNewKey() wgkey.Private {
-	key, err := wgkey.NewPrivate()
-	if err != nil {
-		log.Fatal(err)
-	}
-	return key
-}
-
 func writeNewConfig() config {
-	key := mustNewKey()
+	k := key.NewNode()
 	if err := os.MkdirAll(filepath.Dir(*configPath), 0777); err != nil {
 		log.Fatal(err)
 	}
 	cfg := config{
-		PrivateKey: key,
+		PrivateKey: k,
 	}
 	b, err := json.MarshalIndent(cfg, "", "\t")
 	if err != nil {
@@ -111,27 +136,25 @@ func main() {
 	flag.Parse()
 
 	if *dev {
-		*logCollection = ""
 		*addr = ":3340" // above the keys DERP
 		log.Printf("Running in dev mode.")
 		tsweb.DevMode = true
 	}
 
-	var logPol *logpolicy.Policy
-	if *logCollection != "" {
-		logPol = logpolicy.New(*logCollection)
-		log.SetOutput(logPol.Logtail)
+	listenHost, _, err := net.SplitHostPort(*addr)
+	if err != nil {
+		log.Fatalf("invalid server address: %v", err)
 	}
 
 	cfg := loadConfig()
 
-	letsEncrypt := tsweb.IsProd443(*addr)
+	serveTLS := tsweb.IsProd443(*addr) || *certMode == "manual"
 
-	s := derp.NewServer(key.Private(cfg.PrivateKey), log.Printf)
+	s := derp.NewServer(cfg.PrivateKey, log.Printf)
 	s.SetVerifyClient(*verifyClients)
 
 	if *meshPSKFile != "" {
-		b, err := ioutil.ReadFile(*meshPSKFile)
+		b, err := os.ReadFile(*meshPSKFile)
 		if err != nil {
 			log.Fatal(err)
 		}
@@ -148,10 +171,20 @@ func main() {
 	expvar.Publish("derp", s.ExpVar())
 
 	mux := http.NewServeMux()
-	mux.Handle("/derp", derphttp.Handler(s))
+	if *runDERP {
+		derpHandler := derphttp.Handler(s)
+		derpHandler = addWebSocketSupport(s, derpHandler)
+		mux.Handle("/derp", derpHandler)
+	} else {
+		mux.Handle("/derp", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			http.Error(w, "derp server disabled", http.StatusNotFound)
+		}))
+	}
+	mux.HandleFunc("/derp/probe", probeHandler)
 	go refreshBootstrapDNSLoop()
-	mux.HandleFunc("/bootstrap-dns", handleBootstrapDNS)
+	mux.HandleFunc("/bootstrap-dns", tsweb.BrowserHeaderHandlerFunc(handleBootstrapDNS))
 	mux.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		tsweb.AddBrowserHeaders(w)
 		w.Header().Set("Content-Type", "text/html; charset=utf-8")
 		w.WriteHeader(200)
 		io.WriteString(w, `<html><body>
@@ -163,10 +196,18 @@ func main() {
   server.
 </p>
 `)
+		if !*runDERP {
+			io.WriteString(w, `<p>Status: <b>disabled</b></p>`)
+		}
 		if tsweb.AllowDebugAccess(r) {
 			io.WriteString(w, "<p>Debug info at <a href='/debug/'>/debug/</a>.</p>\n")
 		}
 	}))
+	mux.Handle("/robots.txt", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		tsweb.AddBrowserHeaders(w)
+		io.WriteString(w, "User-agent: *\nDisallow: /\n")
+	}))
+	mux.Handle("/generate_204", http.HandlerFunc(serveNoContent))
 	debug := tsweb.Debugger(mux)
 	debug.KV("TLS hostname", *hostname)
 	debug.KV("Mesh key", s.HasMeshKey())
@@ -181,48 +222,90 @@ func main() {
 	debug.Handle("traffic", "Traffic check", http.HandlerFunc(s.ServeDebugTraffic))
 
 	if *runSTUN {
-		go serveSTUN()
+		go serveSTUN(listenHost, *stunPort)
 	}
 
+	quietLogger := log.New(logFilter{}, "", 0)
 	httpsrv := &http.Server{
-		Addr:    *addr,
-		Handler: mux,
+		Addr:     *addr,
+		Handler:  mux,
+		ErrorLog: quietLogger,
+
+		// Set read/write timeout. For derper, this basically
+		// only affects TLS setup, as read/write deadlines are
+		// cleared on Hijack, which the DERP server does. But
+		// without this, we slowly accumulate stuck TLS
+		// handshake goroutines forever. This also affects
+		// /debug/ traffic, but 30 seconds is plenty for
+		// Prometheus/etc scraping.
+		ReadTimeout:  30 * time.Second,
+		WriteTimeout: 30 * time.Second,
 	}
 
-	var err error
-	if letsEncrypt {
-		if *certDir == "" {
-			log.Fatalf("missing required --certdir flag")
-		}
+	if serveTLS {
 		log.Printf("derper: serving on %s with TLS", *addr)
-		certManager := &autocert.Manager{
-			Prompt:     autocert.AcceptTOS,
-			HostPolicy: autocert.HostWhitelist(*hostname),
-			Cache:      autocert.DirCache(*certDir),
-		}
-		if *hostname == "derp.tailscale.com" {
-			certManager.HostPolicy = prodAutocertHostPolicy
-			certManager.Email = "security@tailscale.com"
+		var certManager certProvider
+		certManager, err = certProviderByCertMode(*certMode, *certDir, *hostname)
+		if err != nil {
+			log.Fatalf("derper: can not start cert provider: %v", err)
 		}
 		httpsrv.TLSConfig = certManager.TLSConfig()
-		letsEncryptGetCert := httpsrv.TLSConfig.GetCertificate
+		getCert := httpsrv.TLSConfig.GetCertificate
 		httpsrv.TLSConfig.GetCertificate = func(hi *tls.ClientHelloInfo) (*tls.Certificate, error) {
-			cert, err := letsEncryptGetCert(hi)
+			cert, err := getCert(hi)
 			if err != nil {
 				return nil, err
 			}
 			cert.Certificate = append(cert.Certificate, s.MetaCert())
 			return cert, nil
 		}
-		go func() {
-			err := http.ListenAndServe(":80", certManager.HTTPHandler(tsweb.Port80Handler{Main: mux}))
-			if err != nil {
-				if err != http.ErrServerClosed {
-					log.Fatal(err)
+		// Disable TLS 1.0 and 1.1, which are obsolete and have security issues.
+		httpsrv.TLSConfig.MinVersion = tls.VersionTLS12
+		httpsrv.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			if r.TLS != nil {
+				label := "unknown"
+				switch r.TLS.Version {
+				case tls.VersionTLS10:
+					label = "1.0"
+				case tls.VersionTLS11:
+					label = "1.1"
+				case tls.VersionTLS12:
+					label = "1.2"
+				case tls.VersionTLS13:
+					label = "1.3"
 				}
+				tlsRequestVersion.Add(label, 1)
+				tlsActiveVersion.Add(label, 1)
+				defer tlsActiveVersion.Add(label, -1)
 			}
-		}()
-		err = httpsrv.ListenAndServeTLS("", "")
+
+			mux.ServeHTTP(w, r)
+		})
+		if *httpPort > -1 {
+			go func() {
+				port80mux := http.NewServeMux()
+				port80mux.HandleFunc("/generate_204", serveNoContent)
+				port80mux.Handle("/", certManager.HTTPHandler(tsweb.Port80Handler{Main: mux}))
+				port80srv := &http.Server{
+					Addr:        net.JoinHostPort(listenHost, fmt.Sprintf("%d", *httpPort)),
+					Handler:     port80mux,
+					ErrorLog:    quietLogger,
+					ReadTimeout: 30 * time.Second,
+					// Crank up WriteTimeout a bit more than usually
+					// necessary just so we can do long CPU profiles
+					// and not hit net/http/pprof's "profile
+					// duration exceeds server's WriteTimeout".
+					WriteTimeout: 5 * time.Minute,
+				}
+				err := port80srv.ListenAndServe()
+				if err != nil {
+					if err != http.ErrServerClosed {
+						log.Fatal(err)
+					}
+				}
+			}()
+		}
+		err = rateLimitedListenAndServeTLS(httpsrv)
 	} else {
 		log.Printf("derper: serving on %s", *addr)
 		err = httpsrv.ListenAndServe()
@@ -232,45 +315,69 @@ func main() {
 	}
 }
 
-func serveSTUN() {
-	pc, err := net.ListenPacket("udp", ":3478")
+const (
+	noContentChallengeHeader = "X-Tailscale-Challenge"
+	noContentResponseHeader  = "X-Tailscale-Response"
+)
+
+// For captive portal detection
+func serveNoContent(w http.ResponseWriter, r *http.Request) {
+	if challenge := r.Header.Get(noContentChallengeHeader); challenge != "" {
+		badChar := strings.IndexFunc(challenge, func(r rune) bool {
+			return !isChallengeChar(r)
+		}) != -1
+		if len(challenge) <= 64 && !badChar {
+			w.Header().Set(noContentResponseHeader, "response "+challenge)
+		}
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+func isChallengeChar(c rune) bool {
+	// Semi-randomly chosen as a limited set of valid characters
+	return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') ||
+		('0' <= c && c <= '9') ||
+		c == '.' || c == '-' || c == '_'
+}
+
+// probeHandler is the endpoint that js/wasm clients hit to measure
+// DERP latency, since they can't do UDP STUN queries.
+func probeHandler(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case "HEAD", "GET":
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+	default:
+		http.Error(w, "bogus probe method", http.StatusMethodNotAllowed)
+	}
+}
+
+func serveSTUN(host string, port int) {
+	pc, err := net.ListenPacket("udp", net.JoinHostPort(host, fmt.Sprint(port)))
 	if err != nil {
 		log.Fatalf("failed to open STUN listener: %v", err)
 	}
 	log.Printf("running STUN server on %v", pc.LocalAddr())
+	serverSTUNListener(context.Background(), pc.(*net.UDPConn))
+}
 
-	var (
-		stats           = new(metrics.Set)
-		stunDisposition = &metrics.LabelMap{Label: "disposition"}
-		stunAddrFamily  = &metrics.LabelMap{Label: "family"}
-
-		stunReadError  = stunDisposition.Get("read_error")
-		stunNotSTUN    = stunDisposition.Get("not_stun")
-		stunWriteError = stunDisposition.Get("write_error")
-		stunSuccess    = stunDisposition.Get("success")
-
-		stunIPv4 = stunAddrFamily.Get("ipv4")
-		stunIPv6 = stunAddrFamily.Get("ipv6")
-	)
-	stats.Set("counter_requests", stunDisposition)
-	stats.Set("counter_addrfamily", stunAddrFamily)
-	expvar.Publish("stun", stats)
-
+func serverSTUNListener(ctx context.Context, pc *net.UDPConn) {
 	var buf [64 << 10]byte
+	var (
+		n   int
+		ua  *net.UDPAddr
+		err error
+	)
 	for {
-		n, addr, err := pc.ReadFrom(buf[:])
+		n, ua, err = pc.ReadFromUDP(buf[:])
 		if err != nil {
+			if ctx.Err() != nil {
+				return
+			}
 			log.Printf("STUN ReadFrom: %v", err)
 			time.Sleep(time.Second)
 			stunReadError.Add(1)
 			continue
 		}
-		ua, ok := addr.(*net.UDPAddr)
-		if !ok {
-			log.Printf("STUN unexpected address %T %v", addr, addr)
-			stunReadError.Add(1)
-			continue
-		}
 		pkt := buf[:n]
 		if !stun.Is(pkt) {
 			stunNotSTUN.Add(1)
@@ -286,8 +393,9 @@ func serveSTUN() {
 		} else {
 			stunIPv6.Add(1)
 		}
-		res := stun.Response(txid, ua.IP, uint16(ua.Port))
-		_, err = pc.WriteTo(res, addr)
+		addr, _ := netip.AddrFromSlice(ua.IP)
+		res := stun.Response(txid, netip.AddrPortFrom(addr, uint16(ua.Port)))
+		_, err = pc.WriteTo(res, ua)
 		if err != nil {
 			stunWriteError.Add(1)
 		} else {
@@ -317,3 +425,78 @@ func defaultMeshPSKFile() string {
 	}
 	return ""
 }
+
+func rateLimitedListenAndServeTLS(srv *http.Server) error {
+	ln, err := net.Listen("tcp", cmpx.Or(srv.Addr, ":https"))
+	if err != nil {
+		return err
+	}
+	rln := newRateLimitedListener(ln, rate.Limit(*acceptConnLimit), *acceptConnBurst)
+	expvar.Publish("tls_listener", rln.ExpVar())
+	defer rln.Close()
+	return srv.ServeTLS(rln, "", "")
+}
+
+type rateLimitedListener struct {
+	// These are at the start of the struct to ensure 64-bit alignment
+	// on 32-bit architecture regardless of what other fields may exist
+	// in this package.
+	numAccepts expvar.Int // does not include number of rejects
+	numRejects expvar.Int
+
+	net.Listener
+
+	lim *rate.Limiter
+}
+
+func newRateLimitedListener(ln net.Listener, limit rate.Limit, burst int) *rateLimitedListener {
+	return &rateLimitedListener{Listener: ln, lim: rate.NewLimiter(limit, burst)}
+}
+
+func (l *rateLimitedListener) ExpVar() expvar.Var {
+	m := new(metrics.Set)
+	m.Set("counter_accepted_connections", &l.numAccepts)
+	m.Set("counter_rejected_connections", &l.numRejects)
+	return m
+}
+
+var errLimitedConn = errors.New("cannot accept connection; rate limited")
+
+func (l *rateLimitedListener) Accept() (net.Conn, error) {
+	// Even under a rate limited situation, we accept the connection immediately
+	// and close it, rather than being slow at accepting new connections.
+	// This provides two benefits: 1) it signals to the client that something
+	// is going on on the server, and 2) it prevents new connections from
+	// piling up and occupying resources in the OS kernel.
+	// The client will retry as needing (with backoffs in place).
+	cn, err := l.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+	if !l.lim.Allow() {
+		l.numRejects.Add(1)
+		cn.Close()
+		return nil, errLimitedConn
+	}
+	l.numAccepts.Add(1)
+	return cn, nil
+}
+
+// logFilter is used to filter out useless error logs that are logged to
+// the net/http.Server.ErrorLog logger.
+type logFilter struct{}
+
+func (logFilter) Write(p []byte) (int, error) {
+	b := mem.B(p)
+	if mem.HasSuffix(b, mem.S(": EOF\n")) ||
+		mem.HasSuffix(b, mem.S(": i/o timeout\n")) ||
+		mem.HasSuffix(b, mem.S(": read: connection reset by peer\n")) ||
+		mem.HasSuffix(b, mem.S(": remote error: tls: bad certificate\n")) ||
+		mem.HasSuffix(b, mem.S(": tls: first record does not look like a TLS handshake\n")) {
+		// Skip this log message, but say that we processed it
+		return len(p), nil
+	}
+
+	log.Printf("%s", p)
+	return len(p), nil
+}

cmd/derper/derper_test.go

@@ -1,12 +1,17 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 package main
 
 import (
 	"context"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"strings"
 	"testing"
+
+	"tailscale.com/net/stun"
 )
 
 func TestProdAutocertHostPolicy(t *testing.T) {
@@ -31,5 +36,95 @@ func TestProdAutocertHostPolicy(t *testing.T) {
 			t.Errorf("f(%q) = %v; want %v", tt.in, got, tt.wantOK)
 		}
 	}
+}
+
+func BenchmarkServerSTUN(b *testing.B) {
+	b.ReportAllocs()
+	pc, err := net.ListenPacket("udp", "127.0.0.1:0")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer pc.Close()
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go serverSTUNListener(ctx, pc.(*net.UDPConn))
+	addr := pc.LocalAddr().(*net.UDPAddr)
+
+	var resBuf [1500]byte
+	cc, err := net.ListenUDP("udp", &net.UDPAddr{IP: net.ParseIP("127.0.0.1")})
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	tx := stun.NewTxID()
+	req := stun.Request(tx)
+	for i := 0; i < b.N; i++ {
+		if _, err := cc.WriteToUDP(req, addr); err != nil {
+			b.Fatal(err)
+		}
+		_, _, err := cc.ReadFromUDP(resBuf[:])
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
 
 }
+
+func TestNoContent(t *testing.T) {
+	testCases := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{
+			name: "no challenge",
+		},
+		{
+			name:  "valid challenge",
+			input: "input",
+			want:  "response input",
+		},
+		{
+			name:  "valid challenge hostname",
+			input: "ts_derp99b.tailscale.com",
+			want:  "response ts_derp99b.tailscale.com",
+		},
+		{
+			name:  "invalid challenge",
+			input: "foo\x00bar",
+			want:  "",
+		},
+		{
+			name:  "whitespace invalid challenge",
+			input: "foo bar",
+			want:  "",
+		},
+		{
+			name:  "long challenge",
+			input: strings.Repeat("x", 65),
+			want:  "",
+		},
+	}
+	for _, tt := range testCases {
+		t.Run(tt.name, func(t *testing.T) {
+			req, _ := http.NewRequest("GET", "https://localhost/generate_204", nil)
+			if tt.input != "" {
+				req.Header.Set(noContentChallengeHeader, tt.input)
+			}
+			w := httptest.NewRecorder()
+			serveNoContent(w, req)
+			resp := w.Result()
+
+			if tt.want == "" {
+				if h, found := resp.Header[noContentResponseHeader]; found {
+					t.Errorf("got %+v; expected no response header", h)
+				}
+				return
+			}
+
+			if got := resp.Header.Get(noContentResponseHeader); got != tt.want {
+				t.Errorf("got %q; want %q", got, tt.want)
+			}
+		})
+	}
+}

cmd/derper/mesh.go

@@ -1,6 +1,5 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 package main
 
@@ -50,8 +49,7 @@ func startMeshWithHost(s *derp.Server, host string) error {
 		}
 		var d net.Dialer
 		var r net.Resolver
-		if port == "443" && strings.HasSuffix(host, ".tailscale.com") {
-			base := strings.TrimSuffix(host, ".tailscale.com")
+		if base, ok := strings.CutSuffix(host, ".tailscale.com"); ok && port == "443" {
 			subCtx, cancel := context.WithTimeout(ctx, 2*time.Second)
 			defer cancel()
 			vpcHost := base + "-vpc.tailscale.com"
@@ -69,8 +67,8 @@ func startMeshWithHost(s *derp.Server, host string) error {
 		return d.DialContext(ctx, network, addr)
 	})
 
-	add := func(k key.Public) { s.AddPacketForwarder(k, c) }
-	remove := func(k key.Public) { s.RemovePacketForwarder(k, c) }
+	add := func(k key.NodePublic) { s.AddPacketForwarder(k, c) }
+	remove := func(k key.NodePublic) { s.RemovePacketForwarder(k, c) }
 	go c.RunWatchConnectionLoop(context.Background(), s.PublicKey(), logf, add, remove)
 	return nil
 }

cmd/derper/websocket.go

@@ -0,0 +1,57 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"bufio"
+	"expvar"
+	"log"
+	"net/http"
+	"strings"
+
+	"nhooyr.io/websocket"
+	"tailscale.com/derp"
+	"tailscale.com/net/wsconn"
+)
+
+var counterWebSocketAccepts = expvar.NewInt("derp_websocket_accepts")
+
+// addWebSocketSupport returns a Handle wrapping base that adds WebSocket server support.
+func addWebSocketSupport(s *derp.Server, base http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		up := strings.ToLower(r.Header.Get("Upgrade"))
+
+		// Very early versions of Tailscale set "Upgrade: WebSocket" but didn't actually
+		// speak WebSockets (they still assumed DERP's binary framing). So to distinguish
+		// clients that actually want WebSockets, look for an explicit "derp" subprotocol.
+		if up != "websocket" || !strings.Contains(r.Header.Get("Sec-Websocket-Protocol"), "derp") {
+			base.ServeHTTP(w, r)
+			return
+		}
+
+		c, err := websocket.Accept(w, r, &websocket.AcceptOptions{
+			Subprotocols:   []string{"derp"},
+			OriginPatterns: []string{"*"},
+			// Disable compression because we transmit WireGuard messages that
+			// are not compressible.
+			// Additionally, Safari has a broken implementation of compression
+			// (see https://github.com/nhooyr/websocket/issues/218) that makes
+			// enabling it actively harmful.
+			CompressionMode: websocket.CompressionDisabled,
+		})
+		if err != nil {
+			log.Printf("websocket.Accept: %v", err)
+			return
+		}
+		defer c.Close(websocket.StatusInternalError, "closing")
+		if c.Subprotocol() != "derp" {
+			c.Close(websocket.StatusPolicyViolation, "client must speak the derp subprotocol")
+			return
+		}
+		counterWebSocketAccepts.Add(1)
+		wc := wsconn.NetConn(r.Context(), c, websocket.MessageBinary)
+		brw := bufio.NewReadWriter(bufio.NewReader(wc), bufio.NewWriter(wc))
+		s.Accept(r.Context(), wc, brw, r.RemoteAddr)
+	})
+}

cmd/derpprobe/derpprobe.go

@@ -1,15 +1,10 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // The derpprobe binary probes derpers.
-package main // import "tailscale.com/cmd/derper/derpprobe"
+package main
 
 import (
-	"bytes"
-	"context"
-	crand "crypto/rand"
-	"encoding/json"
 	"flag"
 	"fmt"
 	"html"
@@ -17,338 +12,99 @@ import (
 	"log"
 	"net/http"
 	"sort"
-	"sync"
 	"time"
 
-	"tailscale.com/derp"
-	"tailscale.com/derp/derphttp"
-	"tailscale.com/tailcfg"
-	"tailscale.com/types/key"
+	"tailscale.com/prober"
+	"tailscale.com/tsweb"
 )
 
 var (
 	derpMapURL = flag.String("derp-map", "https://login.tailscale.com/derpmap/default", "URL to DERP map (https:// or file://)")
 	listen     = flag.String("listen", ":8030", "HTTP listen address")
-)
-
-var (
-	mu            sync.Mutex
-	state         = map[nodePair]pairStatus{}
-	lastDERPMap   *tailcfg.DERPMap
-	lastDERPMapAt time.Time
+	probeOnce  = flag.Bool("once", false, "probe once and print results, then exit; ignores the listen flag")
+	spread     = flag.Bool("spread", true, "whether to spread probing over time")
+	interval   = flag.Duration("interval", 15*time.Second, "probe interval")
 )
 
 func main() {
 	flag.Parse()
-	go probeLoop()
-	log.Fatal(http.ListenAndServe(*listen, http.HandlerFunc(serve)))
+
+	p := prober.New().WithSpread(*spread).WithOnce(*probeOnce).WithMetricNamespace("derpprobe")
+	dp, err := prober.DERP(p, *derpMapURL, *interval, *interval, *interval)
+	if err != nil {
+		log.Fatal(err)
+	}
+	p.Run("derpmap-probe", *interval, nil, dp.ProbeMap)
+
+	if *probeOnce {
+		log.Printf("Waiting for all probes (may take up to 1m)")
+		p.Wait()
+
+		st := getOverallStatus(p)
+		for _, s := range st.good {
+			log.Printf("good: %s", s)
+		}
+		for _, s := range st.bad {
+			log.Printf("bad: %s", s)
+		}
+		return
+	}
+
+	mux := http.NewServeMux()
+	tsweb.Debugger(mux)
+	mux.HandleFunc("/", http.HandlerFunc(serveFunc(p)))
+	log.Fatal(http.ListenAndServe(*listen, mux))
 }
 
 type overallStatus struct {
 	good, bad []string
 }
 
-func (st *overallStatus) addBadf(format string, a ...interface{}) {
+func (st *overallStatus) addBadf(format string, a ...any) {
 	st.bad = append(st.bad, fmt.Sprintf(format, a...))
 }
 
-func (st *overallStatus) addGoodf(format string, a ...interface{}) {
+func (st *overallStatus) addGoodf(format string, a ...any) {
 	st.good = append(st.good, fmt.Sprintf(format, a...))
 }
 
-func getOverallStatus() (o overallStatus) {
-	mu.Lock()
-	defer mu.Unlock()
-	if lastDERPMap == nil {
-		o.addBadf("no DERP map")
-		return
-	}
-	now := time.Now()
-	if age := now.Sub(lastDERPMapAt); age > time.Minute {
-		o.addBadf("DERPMap hasn't been successfully refreshed in %v", age.Round(time.Second))
-	}
-	for _, reg := range sortedRegions(lastDERPMap) {
-		for _, from := range reg.Nodes {
-			for _, to := range reg.Nodes {
-				pair := nodePair{from.Name, to.Name}
-				st, ok := state[pair]
-				age := now.Sub(st.at).Round(time.Second)
-				switch {
-				case !ok:
-					o.addBadf("no state for %v", pair)
-				case st.err != nil:
-					o.addBadf("%v: %v", pair, st.err)
-				case age > 90*time.Second:
-					o.addBadf("%v: update is %v old", pair, age)
-				default:
-					o.addGoodf("%v: %v, %v ago", pair, st.latency.Round(time.Millisecond), age)
-				}
-			}
+func getOverallStatus(p *prober.Prober) (o overallStatus) {
+	for p, i := range p.ProbeInfo() {
+		if i.End.IsZero() {
+			// Do not show probes that have not finished yet.
+			continue
+		}
+		if i.Result {
+			o.addGoodf("%s: %s", p, i.Latency)
+		} else {
+			o.addBadf("%s: %s", p, i.Error)
 		}
 	}
+
+	sort.Strings(o.bad)
+	sort.Strings(o.good)
 	return
 }
 
-func serve(w http.ResponseWriter, r *http.Request) {
-	st := getOverallStatus()
-	summary := "All good"
-	if len(st.bad) > 0 {
-		w.WriteHeader(500)
-		summary = fmt.Sprintf("%d problems", len(st.bad))
-	}
-	io.WriteString(w, "<html><head><style>.bad { font-weight: bold; color: #700; }</style></head>\n")
-	fmt.Fprintf(w, "<body><h1>derp probe</h1>\n%s:<ul>", summary)
-	for _, s := range st.bad {
-		fmt.Fprintf(w, "<li class=bad>%s</li>\n", html.EscapeString(s))
-	}
-	for _, s := range st.good {
-		fmt.Fprintf(w, "<li>%s</li>\n", html.EscapeString(s))
-	}
-	io.WriteString(w, "</ul></body></html>\n")
-}
-
-func sortedRegions(dm *tailcfg.DERPMap) []*tailcfg.DERPRegion {
-	ret := make([]*tailcfg.DERPRegion, 0, len(dm.Regions))
-	for _, r := range dm.Regions {
-		ret = append(ret, r)
-	}
-	sort.Slice(ret, func(i, j int) bool { return ret[i].RegionID < ret[j].RegionID })
-	return ret
-}
-
-type nodePair struct {
-	from, to string // DERPNode.Name
-}
-
-func (p nodePair) String() string { return fmt.Sprintf("(%s→%s)", p.from, p.to) }
-
-type pairStatus struct {
-	err     error
-	latency time.Duration
-	at      time.Time
-}
-
-func setDERPMap(dm *tailcfg.DERPMap) {
-	mu.Lock()
-	defer mu.Unlock()
-	lastDERPMap = dm
-	lastDERPMapAt = time.Now()
-}
-
-func setState(p nodePair, latency time.Duration, err error) {
-	mu.Lock()
-	defer mu.Unlock()
-	st := pairStatus{
-		err:     err,
-		latency: latency,
-		at:      time.Now(),
-	}
-	state[p] = st
-	if err != nil {
-		log.Printf("%+v error: %v", p, err)
-	} else {
-		log.Printf("%+v: %v", p, latency.Round(time.Millisecond))
-	}
-}
-
-func probeLoop() {
-	ticker := time.NewTicker(15 * time.Second)
-	for {
-		err := probe()
-		if err != nil {
-			log.Printf("probe: %v", err)
+func serveFunc(p *prober.Prober) func(w http.ResponseWriter, r *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		st := getOverallStatus(p)
+		summary := "All good"
+		if (float64(len(st.bad)) / float64(len(st.bad)+len(st.good))) > 0.25 {
+			// Returning a 500 allows monitoring this server externally and configuring
+			// an alert on HTTP response code.
+			w.WriteHeader(500)
+			summary = fmt.Sprintf("%d problems", len(st.bad))
 		}
-		<-ticker.C
+
+		io.WriteString(w, "<html><head><style>.bad { font-weight: bold; color: #700; }</style></head>\n")
+		fmt.Fprintf(w, "<body><h1>derp probe</h1>\n%s:<ul>", summary)
+		for _, s := range st.bad {
+			fmt.Fprintf(w, "<li class=bad>%s</li>\n", html.EscapeString(s))
+		}
+		for _, s := range st.good {
+			fmt.Fprintf(w, "<li>%s</li>\n", html.EscapeString(s))
+		}
+		io.WriteString(w, "</ul></body></html>\n")
 	}
 }
-
-func probe() error {
-	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
-	defer cancel()
-	dm, err := getDERPMap(ctx)
-	if err != nil {
-		return err
-	}
-
-	var wg sync.WaitGroup
-	wg.Add(len(dm.Regions))
-	for _, reg := range dm.Regions {
-		reg := reg
-		go func() {
-			defer wg.Done()
-			for _, from := range reg.Nodes {
-				for _, to := range reg.Nodes {
-					latency, err := probeNodePair(ctx, dm, from, to)
-					setState(nodePair{from.Name, to.Name}, latency, err)
-				}
-			}
-		}()
-	}
-
-	wg.Wait()
-	return ctx.Err()
-}
-
-func probeNodePair(ctx context.Context, dm *tailcfg.DERPMap, from, to *tailcfg.DERPNode) (latency time.Duration, err error) {
-	// The passed in context is a minute for the whole region. The
-	// idea is that each node pair in the region will be done
-	// serially and regularly in the future, reusing connections
-	// (at least in the happy path). For now they don't reuse
-	// connections and probe at most once every 15 seconds. We
-	// bound the duration of a single node pair within a region
-	// so one bad one can't starve others.
-	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
-	defer cancel()
-
-	fromc, err := newConn(ctx, dm, from)
-	if err != nil {
-		return 0, err
-	}
-	defer fromc.Close()
-	toc, err := newConn(ctx, dm, to)
-	if err != nil {
-		return 0, err
-	}
-	defer toc.Close()
-
-	// Wait a bit for from's node to hear about to existing on the
-	// other node in the region, in the case where the two nodes
-	// are different.
-	if from.Name != to.Name {
-		time.Sleep(100 * time.Millisecond) // pretty arbitrary
-	}
-
-	// Make a random packet
-	pkt := make([]byte, 8)
-	crand.Read(pkt)
-
-	t0 := time.Now()
-
-	// Send the random packet.
-	sendc := make(chan error, 1)
-	go func() {
-		sendc <- fromc.Send(toc.SelfPublicKey(), pkt)
-	}()
-	select {
-	case <-ctx.Done():
-		return 0, fmt.Errorf("timeout sending via %q: %w", from.Name, ctx.Err())
-	case err := <-sendc:
-		if err != nil {
-			return 0, fmt.Errorf("error sending via %q: %w", from.Name, err)
-		}
-	}
-
-	// Receive the random packet.
-	recvc := make(chan interface{}, 1) // either derp.ReceivedPacket or error
-	go func() {
-		for {
-			m, err := toc.Recv()
-			if err != nil {
-				recvc <- err
-				return
-			}
-			switch v := m.(type) {
-			case derp.ReceivedPacket:
-				recvc <- v
-			default:
-				log.Printf("%v: ignoring Recv frame type %T", to.Name, v)
-				// Loop.
-			}
-		}
-	}()
-	select {
-	case <-ctx.Done():
-		return 0, fmt.Errorf("timeout receiving from %q: %w", to.Name, ctx.Err())
-	case v := <-recvc:
-		if err, ok := v.(error); ok {
-			return 0, fmt.Errorf("error receiving from %q: %w", to.Name, err)
-		}
-		p := v.(derp.ReceivedPacket)
-		if p.Source != fromc.SelfPublicKey() {
-			return 0, fmt.Errorf("got data packet from unexpected source, %v", p.Source)
-		}
-		if !bytes.Equal(p.Data, pkt) {
-			return 0, fmt.Errorf("unexpected data packet %q", p.Data)
-		}
-	}
-	return time.Since(t0), nil
-}
-
-func newConn(ctx context.Context, dm *tailcfg.DERPMap, n *tailcfg.DERPNode) (*derphttp.Client, error) {
-	priv := key.NewPrivate()
-	dc := derphttp.NewRegionClient(priv, log.Printf, func() *tailcfg.DERPRegion {
-		rid := n.RegionID
-		return &tailcfg.DERPRegion{
-			RegionID:   rid,
-			RegionCode: fmt.Sprintf("%s-%s", dm.Regions[rid].RegionCode, n.Name),
-			RegionName: dm.Regions[rid].RegionName,
-			Nodes:      []*tailcfg.DERPNode{n},
-		}
-	})
-	dc.IsProber = true
-	err := dc.Connect(ctx)
-	if err != nil {
-		return nil, err
-	}
-	errc := make(chan error, 1)
-	go func() {
-		m, err := dc.Recv()
-		if err != nil {
-			errc <- err
-			return
-		}
-		switch m.(type) {
-		case derp.ServerInfoMessage:
-			errc <- nil
-		default:
-			errc <- fmt.Errorf("unexpected first message type %T", errc)
-		}
-	}()
-	select {
-	case err := <-errc:
-		if err != nil {
-			go dc.Close()
-			return nil, err
-		}
-	case <-ctx.Done():
-		go dc.Close()
-		return nil, fmt.Errorf("timeout waiting for ServerInfoMessage: %w", ctx.Err())
-	}
-	return dc, nil
-}
-
-var httpOrFileClient = &http.Client{Transport: httpOrFileTransport()}
-
-func httpOrFileTransport() http.RoundTripper {
-	tr := http.DefaultTransport.(*http.Transport).Clone()
-	tr.RegisterProtocol("file", http.NewFileTransport(http.Dir("/")))
-	return tr
-}
-
-func getDERPMap(ctx context.Context) (*tailcfg.DERPMap, error) {
-	req, err := http.NewRequestWithContext(ctx, "GET", *derpMapURL, nil)
-	if err != nil {
-		return nil, err
-	}
-	res, err := httpOrFileClient.Do(req)
-	if err != nil {
-		mu.Lock()
-		defer mu.Unlock()
-		if lastDERPMap != nil && time.Since(lastDERPMapAt) < 10*time.Minute {
-			// Assume that control is restarting and use
-			// the same one for a bit.
-			return lastDERPMap, nil
-		}
-		return nil, err
-	}
-	defer res.Body.Close()
-	if res.StatusCode != 200 {
-		return nil, fmt.Errorf("fetching %s: %s", *derpMapURL, res.Status)
-	}
-	dm := new(tailcfg.DERPMap)
-	if err := json.NewDecoder(res.Body).Decode(dm); err != nil {
-		return nil, fmt.Errorf("decoding %s JSON: %v", *derpMapURL, err)
-	}
-	setDERPMap(dm)
-	return dm, nil
-}

cmd/dist/dist.go

@@ -0,0 +1,51 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// The dist command builds Tailscale release packages for distribution.
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"log"
+	"os"
+
+	"tailscale.com/release/dist"
+	"tailscale.com/release/dist/cli"
+	"tailscale.com/release/dist/synology"
+	"tailscale.com/release/dist/unixpkgs"
+)
+
+var synologyPackageCenter bool
+
+func getTargets() ([]dist.Target, error) {
+	var ret []dist.Target
+
+	ret = append(ret, unixpkgs.Targets()...)
+	// Synology packages can be built either for sideloading, or for
+	// distribution by Synology in their package center. When
+	// distributed through the package center, apps can request
+	// additional permissions to use a tuntap interface and control
+	// the NAS's network stack, rather than be forced to run in
+	// userspace mode.
+	//
+	// Since only we can provide packages to Synology for
+	// distribution, we default to building the "sideload" variant of
+	// packages that we distribute on pkgs.tailscale.com.
+	ret = append(ret, synology.Targets(synologyPackageCenter)...)
+	return ret, nil
+}
+
+func main() {
+	cmd := cli.CLI(getTargets)
+	for _, subcmd := range cmd.Subcommands {
+		if subcmd.Name == "build" {
+			subcmd.FlagSet.BoolVar(&synologyPackageCenter, "synology-package-center", false, "build synology packages with extra metadata for the official package center")
+		}
+	}
+
+	if err := cmd.ParseAndRun(context.Background(), os.Args[1:]); err != nil && !errors.Is(err, flag.ErrHelp) {
+		log.Fatal(err)
+	}
+}

cmd/get-authkey/.gitignore

@@ -0,0 +1 @@
+get-authkey

cmd/get-authkey/main.go

@@ -0,0 +1,74 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// get-authkey allocates an authkey using an OAuth API client
+// https://tailscale.com/s/oauth-clients and prints it
+// to stdout for scripts to capture and use.
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"strings"
+
+	"golang.org/x/oauth2/clientcredentials"
+	"tailscale.com/client/tailscale"
+	"tailscale.com/util/cmpx"
+)
+
+func main() {
+	// Required to use our client API. We're fine with the instability since the
+	// client lives in the same repo as this code.
+	tailscale.I_Acknowledge_This_API_Is_Unstable = true
+
+	reusable := flag.Bool("reusable", false, "allocate a reusable authkey")
+	ephemeral := flag.Bool("ephemeral", false, "allocate an ephemeral authkey")
+	preauth := flag.Bool("preauth", true, "set the authkey as pre-authorized")
+	tags := flag.String("tags", "", "comma-separated list of tags to apply to the authkey")
+	flag.Parse()
+
+	clientID := os.Getenv("TS_API_CLIENT_ID")
+	clientSecret := os.Getenv("TS_API_CLIENT_SECRET")
+	if clientID == "" || clientSecret == "" {
+		log.Fatal("TS_API_CLIENT_ID and TS_API_CLIENT_SECRET must be set")
+	}
+
+	if *tags == "" {
+		log.Fatal("at least one tag must be specified")
+	}
+
+	baseURL := cmpx.Or(os.Getenv("TS_BASE_URL"), "https://api.tailscale.com")
+
+	credentials := clientcredentials.Config{
+		ClientID:     clientID,
+		ClientSecret: clientSecret,
+		TokenURL:     baseURL + "/api/v2/oauth/token",
+		Scopes:       []string{"device"},
+	}
+
+	ctx := context.Background()
+	tsClient := tailscale.NewClient("-", nil)
+	tsClient.HTTPClient = credentials.Client(ctx)
+	tsClient.BaseURL = baseURL
+
+	caps := tailscale.KeyCapabilities{
+		Devices: tailscale.KeyDeviceCapabilities{
+			Create: tailscale.KeyDeviceCreateCapabilities{
+				Reusable:      *reusable,
+				Ephemeral:     *ephemeral,
+				Preauthorized: *preauth,
+				Tags:          strings.Split(*tags, ","),
+			},
+		},
+	}
+
+	authkey, _, err := tsClient.CreateKey(ctx, caps)
+	if err != nil {
+		log.Fatal(err.Error())
+	}
+
+	fmt.Println(authkey)
+}

cmd/gitops-pusher/.gitignore

@@ -0,0 +1 @@
+version-cache.json

cmd/gitops-pusher/README.md

@@ -0,0 +1,48 @@
+# gitops-pusher
+
+This is a small tool to help people achieve a
+[GitOps](https://about.gitlab.com/topics/gitops/) workflow with Tailscale ACL
+changes. This tool is intended to be used in a CI flow that looks like this:
+
+```yaml
+name: Tailscale ACL syncing
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  acls:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+      
+      - name: Setup Go environment
+        uses: actions/setup-go@v3.2.0
+        
+      - name: Install gitops-pusher
+        run: go install tailscale.com/cmd/gitops-pusher@latest
+              
+      - name: Deploy ACL
+        if: github.event_name == 'push'
+        env:
+          TS_API_KEY: ${{ secrets.TS_API_KEY }}
+          TS_TAILNET: ${{ secrets.TS_TAILNET }}
+        run: |
+          ~/go/bin/gitops-pusher --policy-file ./policy.hujson apply
+
+      - name: ACL tests
+        if: github.event_name == 'pull_request'
+        env:
+          TS_API_KEY: ${{ secrets.TS_API_KEY }}
+          TS_TAILNET: ${{ secrets.TS_TAILNET }}
+        run: |
+          ~/go/bin/gitops-pusher --policy-file ./policy.hujson test
+```
+
+Change the value of the `--policy-file` flag to point to the policy file on
+disk. Policy files should be in [HuJSON](https://github.com/tailscale/hujson)
+format.

cmd/gitops-pusher/cache.go

@@ -0,0 +1,66 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"encoding/json"
+	"os"
+)
+
+// Cache contains cached information about the last time this tool was run.
+//
+// This is serialized to a JSON file that should NOT be checked into git.
+// It should be managed with either CI cache tools or stored locally somehow. The
+// exact mechanism is irrelevant as long as it is consistent.
+//
+// This allows gitops-pusher to detect external ACL changes. I'm not sure what to
+// call this problem, so I've been calling it the "three version problem" in my
+// notes. The basic problem is that at any given time we only have two versions
+// of the ACL file at any given point. In order to check if there has been
+// tampering of the ACL files in the admin panel, we need to have a _third_ version
+// to compare against.
+//
+// In this case I am not storing the old ACL entirely (though that could be a
+// reasonable thing to add in the future), but only its sha256sum. This allows
+// us to detect if the shasum in control matches the shasum we expect, and if that
+// expectation fails, then we can react accordingly.
+type Cache struct {
+	PrevETag string // Stores the previous ETag of the ACL to allow
+}
+
+// Save persists the cache to a given file.
+func (c *Cache) Save(fname string) error {
+	os.Remove(fname)
+	fout, err := os.Create(fname)
+	if err != nil {
+		return err
+	}
+	defer fout.Close()
+
+	return json.NewEncoder(fout).Encode(c)
+}
+
+// LoadCache loads the cache from a given file.
+func LoadCache(fname string) (*Cache, error) {
+	var result Cache
+
+	fin, err := os.Open(fname)
+	if err != nil {
+		return nil, err
+	}
+	defer fin.Close()
+
+	err = json.NewDecoder(fin).Decode(&result)
+	if err != nil {
+		return nil, err
+	}
+
+	return &result, nil
+}
+
+// Shuck removes the first and last character of a string, analogous to
+// shucking off the husk of an ear of corn.
+func Shuck(s string) string {
+	return s[1 : len(s)-1]
+}

cmd/gitops-pusher/gitops-pusher.go

@@ -0,0 +1,397 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Command gitops-pusher allows users to use a GitOps flow for managing Tailscale ACLs.
+//
+// See README.md for more details.
+package main
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/peterbourgon/ff/v3/ffcli"
+	"github.com/tailscale/hujson"
+	"golang.org/x/oauth2/clientcredentials"
+	"tailscale.com/client/tailscale"
+	"tailscale.com/util/httpm"
+)
+
+var (
+	rootFlagSet  = flag.NewFlagSet("gitops-pusher", flag.ExitOnError)
+	policyFname  = rootFlagSet.String("policy-file", "./policy.hujson", "filename for policy file")
+	cacheFname   = rootFlagSet.String("cache-file", "./version-cache.json", "filename for the previous known version hash")
+	timeout      = rootFlagSet.Duration("timeout", 5*time.Minute, "timeout for the entire CI run")
+	githubSyntax = rootFlagSet.Bool("github-syntax", true, "use GitHub Action error syntax (https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#setting-an-error-message)")
+	apiServer    = rootFlagSet.String("api-server", "api.tailscale.com", "API server to contact")
+)
+
+func modifiedExternallyError() {
+	if *githubSyntax {
+		fmt.Printf("::warning file=%s,line=1,col=1,title=Policy File Modified Externally::The policy file was modified externally in the admin console.\n", *policyFname)
+	} else {
+		fmt.Printf("The policy file was modified externally in the admin console.\n")
+	}
+}
+
+func apply(cache *Cache, client *http.Client, tailnet, apiKey string) func(context.Context, []string) error {
+	return func(ctx context.Context, args []string) error {
+		controlEtag, err := getACLETag(ctx, client, tailnet, apiKey)
+		if err != nil {
+			return err
+		}
+
+		localEtag, err := sumFile(*policyFname)
+		if err != nil {
+			return err
+		}
+
+		if cache.PrevETag == "" {
+			log.Println("no previous etag found, assuming local file is correct and recording that")
+			cache.PrevETag = localEtag
+		}
+
+		log.Printf("control: %s", controlEtag)
+		log.Printf("local:   %s", localEtag)
+		log.Printf("cache:   %s", cache.PrevETag)
+
+		if cache.PrevETag != controlEtag {
+			modifiedExternallyError()
+		}
+
+		if controlEtag == localEtag {
+			cache.PrevETag = localEtag
+			log.Println("no update needed, doing nothing")
+			return nil
+		}
+
+		if err := applyNewACL(ctx, client, tailnet, apiKey, *policyFname, controlEtag); err != nil {
+			return err
+		}
+
+		cache.PrevETag = localEtag
+
+		return nil
+	}
+}
+
+func test(cache *Cache, client *http.Client, tailnet, apiKey string) func(context.Context, []string) error {
+	return func(ctx context.Context, args []string) error {
+		controlEtag, err := getACLETag(ctx, client, tailnet, apiKey)
+		if err != nil {
+			return err
+		}
+
+		localEtag, err := sumFile(*policyFname)
+		if err != nil {
+			return err
+		}
+
+		if cache.PrevETag == "" {
+			log.Println("no previous etag found, assuming local file is correct and recording that")
+			cache.PrevETag = localEtag
+		}
+
+		log.Printf("control: %s", controlEtag)
+		log.Printf("local:   %s", localEtag)
+		log.Printf("cache:   %s", cache.PrevETag)
+
+		if cache.PrevETag != controlEtag {
+			modifiedExternallyError()
+		}
+
+		if controlEtag == localEtag {
+			log.Println("no updates found, doing nothing")
+			return nil
+		}
+
+		if err := testNewACLs(ctx, client, tailnet, apiKey, *policyFname); err != nil {
+			return err
+		}
+		return nil
+	}
+}
+
+func getChecksums(cache *Cache, client *http.Client, tailnet, apiKey string) func(context.Context, []string) error {
+	return func(ctx context.Context, args []string) error {
+		controlEtag, err := getACLETag(ctx, client, tailnet, apiKey)
+		if err != nil {
+			return err
+		}
+
+		localEtag, err := sumFile(*policyFname)
+		if err != nil {
+			return err
+		}
+
+		if cache.PrevETag == "" {
+			log.Println("no previous etag found, assuming local file is correct and recording that")
+			cache.PrevETag = Shuck(localEtag)
+		}
+
+		log.Printf("control: %s", controlEtag)
+		log.Printf("local:   %s", localEtag)
+		log.Printf("cache:   %s", cache.PrevETag)
+
+		return nil
+	}
+}
+
+func main() {
+	tailnet, ok := os.LookupEnv("TS_TAILNET")
+	if !ok {
+		log.Fatal("set envvar TS_TAILNET to your tailnet's name")
+	}
+	apiKey, ok := os.LookupEnv("TS_API_KEY")
+	oauthId, oiok := os.LookupEnv("TS_OAUTH_ID")
+	oauthSecret, osok := os.LookupEnv("TS_OAUTH_SECRET")
+	if !ok && (!oiok || !osok) {
+		log.Fatal("set envvar TS_API_KEY to your Tailscale API key or TS_OAUTH_ID and TS_OAUTH_SECRET to your Tailscale OAuth ID and Secret")
+	}
+	if ok && (oiok || osok) {
+		log.Fatal("set either the envvar TS_API_KEY or TS_OAUTH_ID and TS_OAUTH_SECRET")
+	}
+	var client *http.Client
+	if oiok {
+		oauthConfig := &clientcredentials.Config{
+			ClientID:     oauthId,
+			ClientSecret: oauthSecret,
+			TokenURL:     fmt.Sprintf("https://%s/api/v2/oauth/token", *apiServer),
+		}
+		client = oauthConfig.Client(context.Background())
+	} else {
+		client = http.DefaultClient
+	}
+	cache, err := LoadCache(*cacheFname)
+	if err != nil {
+		if os.IsNotExist(err) {
+			cache = &Cache{}
+		} else {
+			log.Fatalf("error loading cache: %v", err)
+		}
+	}
+	defer cache.Save(*cacheFname)
+
+	applyCmd := &ffcli.Command{
+		Name:       "apply",
+		ShortUsage: "gitops-pusher [options] apply",
+		ShortHelp:  "Pushes changes to CONTROL",
+		LongHelp:   `Pushes changes to CONTROL`,
+		Exec:       apply(cache, client, tailnet, apiKey),
+	}
+
+	testCmd := &ffcli.Command{
+		Name:       "test",
+		ShortUsage: "gitops-pusher [options] test",
+		ShortHelp:  "Tests ACL changes",
+		LongHelp:   "Tests ACL changes",
+		Exec:       test(cache, client, tailnet, apiKey),
+	}
+
+	cksumCmd := &ffcli.Command{
+		Name:       "checksum",
+		ShortUsage: "Shows checksums of ACL files",
+		ShortHelp:  "Fetch checksum of CONTROL's ACL and the local ACL for comparison",
+		LongHelp:   "Fetch checksum of CONTROL's ACL and the local ACL for comparison",
+		Exec:       getChecksums(cache, client, tailnet, apiKey),
+	}
+
+	root := &ffcli.Command{
+		ShortUsage:  "gitops-pusher [options] <command>",
+		ShortHelp:   "Push Tailscale ACLs to CONTROL using a GitOps workflow",
+		Subcommands: []*ffcli.Command{applyCmd, cksumCmd, testCmd},
+		FlagSet:     rootFlagSet,
+	}
+
+	if err := root.Parse(os.Args[1:]); err != nil {
+		log.Fatal(err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), *timeout)
+	defer cancel()
+
+	if err := root.Run(ctx); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func sumFile(fname string) (string, error) {
+	data, err := os.ReadFile(fname)
+	if err != nil {
+		return "", err
+	}
+
+	formatted, err := hujson.Format(data)
+	if err != nil {
+		return "", err
+	}
+
+	h := sha256.New()
+	_, err = h.Write(formatted)
+	if err != nil {
+		return "", err
+	}
+
+	return fmt.Sprintf("%x", h.Sum(nil)), nil
+}
+
+func applyNewACL(ctx context.Context, client *http.Client, tailnet, apiKey, policyFname, oldEtag string) error {
+	fin, err := os.Open(policyFname)
+	if err != nil {
+		return err
+	}
+	defer fin.Close()
+
+	req, err := http.NewRequestWithContext(ctx, httpm.POST, fmt.Sprintf("https://%s/api/v2/tailnet/%s/acl", *apiServer, tailnet), fin)
+	if err != nil {
+		return err
+	}
+
+	req.SetBasicAuth(apiKey, "")
+	req.Header.Set("Content-Type", "application/hujson")
+	req.Header.Set("If-Match", `"`+oldEtag+`"`)
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	got := resp.StatusCode
+	want := http.StatusOK
+	if got != want {
+		var ate ACLGitopsTestError
+		err := json.NewDecoder(resp.Body).Decode(&ate)
+		if err != nil {
+			return err
+		}
+
+		return ate
+	}
+
+	return nil
+}
+
+func testNewACLs(ctx context.Context, client *http.Client, tailnet, apiKey, policyFname string) error {
+	data, err := os.ReadFile(policyFname)
+	if err != nil {
+		return err
+	}
+	data, err = hujson.Standardize(data)
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, httpm.POST, fmt.Sprintf("https://%s/api/v2/tailnet/%s/acl/validate", *apiServer, tailnet), bytes.NewBuffer(data))
+	if err != nil {
+		return err
+	}
+
+	req.SetBasicAuth(apiKey, "")
+	req.Header.Set("Content-Type", "application/hujson")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	var ate ACLGitopsTestError
+	err = json.NewDecoder(resp.Body).Decode(&ate)
+	if err != nil {
+		return err
+	}
+
+	if len(ate.Message) != 0 || len(ate.Data) != 0 {
+		return ate
+	}
+
+	got := resp.StatusCode
+	want := http.StatusOK
+	if got != want {
+		return fmt.Errorf("wanted HTTP status code %d but got %d", want, got)
+	}
+
+	return nil
+}
+
+var lineColMessageSplit = regexp.MustCompile(`line ([0-9]+), column ([0-9]+): (.*)$`)
+
+// ACLGitopsTestError is redefined here so we can add a custom .Error() response
+type ACLGitopsTestError struct {
+	tailscale.ACLTestError
+}
+
+func (ate ACLGitopsTestError) Error() string {
+	var sb strings.Builder
+
+	if *githubSyntax && lineColMessageSplit.MatchString(ate.Message) {
+		sp := lineColMessageSplit.FindStringSubmatch(ate.Message)
+
+		line := sp[1]
+		col := sp[2]
+		msg := sp[3]
+
+		fmt.Fprintf(&sb, "::error file=%s,line=%s,col=%s::%s", *policyFname, line, col, msg)
+	} else {
+		fmt.Fprintln(&sb, ate.Message)
+	}
+	fmt.Fprintln(&sb)
+
+	for _, data := range ate.Data {
+		if data.User != "" {
+			fmt.Fprintf(&sb, "For user %s:\n", data.User)
+		}
+
+		if len(data.Errors) > 0 {
+			fmt.Fprint(&sb, "Errors found:\n")
+			for _, err := range data.Errors {
+				fmt.Fprintf(&sb, "- %s\n", err)
+			}
+		}
+
+		if len(data.Warnings) > 0 {
+			fmt.Fprint(&sb, "Warnings found:\n")
+			for _, err := range data.Warnings {
+				fmt.Fprintf(&sb, "- %s\n", err)
+			}
+		}
+	}
+
+	return sb.String()
+}
+
+func getACLETag(ctx context.Context, client *http.Client, tailnet, apiKey string) (string, error) {
+	req, err := http.NewRequestWithContext(ctx, httpm.GET, fmt.Sprintf("https://%s/api/v2/tailnet/%s/acl", *apiServer, tailnet), nil)
+	if err != nil {
+		return "", err
+	}
+
+	req.SetBasicAuth(apiKey, "")
+	req.Header.Set("Accept", "application/hujson")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	got := resp.StatusCode
+	want := http.StatusOK
+	if got != want {
+		return "", fmt.Errorf("wanted HTTP status code %d but got %d", want, got)
+	}
+
+	return Shuck(resp.Header.Get("ETag")), nil
+}

cmd/gitops-pusher/gitops-pusher_test.go

@@ -0,0 +1,55 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+package main
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"tailscale.com/client/tailscale"
+)
+
+func TestEmbeddedTypeUnmarshal(t *testing.T) {
+	var gitopsErr ACLGitopsTestError
+	gitopsErr.Message = "gitops response error"
+	gitopsErr.Data = []tailscale.ACLTestFailureSummary{
+		{
+			User:   "GitopsError",
+			Errors: []string{"this was initially created as a gitops error"},
+		},
+	}
+
+	var aclTestErr tailscale.ACLTestError
+	aclTestErr.Message = "native ACL response error"
+	aclTestErr.Data = []tailscale.ACLTestFailureSummary{
+		{
+			User:   "ACLError",
+			Errors: []string{"this was initially created as an ACL error"},
+		},
+	}
+
+	t.Run("unmarshal gitops type from acl type", func(t *testing.T) {
+		b, _ := json.Marshal(aclTestErr)
+		var e ACLGitopsTestError
+		err := json.Unmarshal(b, &e)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !strings.Contains(e.Error(), "For user ACLError") { // the gitops error prints out the user, the acl error doesn't
+			t.Fatalf("user heading for 'ACLError' not found in gitops error: %v", e.Error())
+		}
+	})
+	t.Run("unmarshal acl type from gitops type", func(t *testing.T) {
+		b, _ := json.Marshal(gitopsErr)
+		var e tailscale.ACLTestError
+		err := json.Unmarshal(b, &e)
+		if err != nil {
+			t.Fatal(err)
+		}
+		expectedErr := `Status: 0, Message: "gitops response error", Data: [{User:GitopsError Errors:[this was initially created as a gitops error] Warnings:[]}]`
+		if e.Error() != expectedErr {
+			t.Fatalf("got %v\n, expected %v", e.Error(), expectedErr)
+		}
+	})
+}

cmd/hello/hello.go

@@ -1,21 +1,22 @@
-// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
-// The hello binary runs hello.ipn.dev.
+// The hello binary runs hello.ts.net.
 package main // import "tailscale.com/cmd/hello"
 
 import (
 	"context"
+	"crypto/tls"
 	_ "embed"
 	"encoding/json"
+	"errors"
 	"flag"
 	"html/template"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
 	"strings"
+	"time"
 
 	"tailscale.com/client/tailscale"
 	"tailscale.com/client/tailscale/apitype"
@@ -69,11 +70,31 @@ func main() {
 	if *httpsAddr != "" {
 		log.Printf("running HTTPS server on %s", *httpsAddr)
 		go func() {
-			errc <- http.ListenAndServeTLS(*httpsAddr,
-				"/etc/hello/hello.ipn.dev.crt",
-				"/etc/hello/hello.ipn.dev.key",
-				nil,
-			)
+			hs := &http.Server{
+				Addr: *httpsAddr,
+				TLSConfig: &tls.Config{
+					GetCertificate: func(hi *tls.ClientHelloInfo) (*tls.Certificate, error) {
+						switch hi.ServerName {
+						case "hello.ts.net":
+							return tailscale.GetCertificate(hi)
+						case "hello.ipn.dev":
+							c, err := tls.LoadX509KeyPair(
+								"/etc/hello/hello.ipn.dev.crt",
+								"/etc/hello/hello.ipn.dev.key",
+							)
+							if err != nil {
+								return nil, err
+							}
+							return &c, nil
+						}
+						return nil, errors.New("invalid SNI name")
+					},
+				},
+				IdleTimeout:       30 * time.Second,
+				ReadHeaderTimeout: 20 * time.Second,
+				MaxHeaderBytes:    10 << 10,
+			}
+			errc <- hs.ListenAndServeTLS("", "")
 		}()
 	}
 	log.Fatal(<-errc)
@@ -83,7 +104,7 @@ func devMode() bool { return *httpsAddr == "" && *httpAddr != "" }
 
 func getTmpl() (*template.Template, error) {
 	if devMode() {
-		tmplData, err := ioutil.ReadFile("hello.tmpl.html")
+		tmplData, err := os.ReadFile("hello.tmpl.html")
 		if os.IsNotExist(err) {
 			log.Printf("using baked-in template in dev mode; can't find hello.tmpl.html in current directory")
 			return tmpl, nil
@@ -112,13 +133,13 @@ func tailscaleIP(who *apitype.WhoIsResponse) string {
 		return ""
 	}
 	for _, nodeIP := range who.Node.Addresses {
-		if nodeIP.IP().Is4() && nodeIP.IsSingleIP() {
-			return nodeIP.IP().String()
+		if nodeIP.Addr().Is4() && nodeIP.IsSingleIP() {
+			return nodeIP.Addr().String()
 		}
 	}
 	for _, nodeIP := range who.Node.Addresses {
 		if nodeIP.IsSingleIP() {
-			return nodeIP.IP().String()
+			return nodeIP.Addr().String()
 		}
 	}
 	return ""
@@ -127,8 +148,9 @@ func tailscaleIP(who *apitype.WhoIsResponse) string {
 func root(w http.ResponseWriter, r *http.Request) {
 	if r.TLS == nil && *httpsAddr != "" {
 		host := r.Host
-		if strings.Contains(r.Host, "100.101.102.103") {
-			host = "hello.ipn.dev"
+		if strings.Contains(r.Host, "100.101.102.103") ||
+			strings.Contains(r.Host, "hello.ipn.dev") {
+			host = "hello.ts.net"
 		}
 		http.Redirect(w, r, "https://"+host, http.StatusFound)
 		return
@@ -137,6 +159,10 @@ func root(w http.ResponseWriter, r *http.Request) {
 		http.Redirect(w, r, "/", http.StatusFound)
 		return
 	}
+	if r.TLS != nil && *httpsAddr != "" && strings.Contains(r.Host, "hello.ipn.dev") {
+		http.Redirect(w, r, "https://hello.ts.net", http.StatusFound)
+		return
+	}
 	tmpl, err := getTmpl()
 	if err != nil {
 		w.Header().Set("Content-Type", "text/plain")
@@ -168,7 +194,7 @@ func root(w http.ResponseWriter, r *http.Request) {
 			LoginName:     who.UserProfile.LoginName,
 			ProfilePicURL: who.UserProfile.ProfilePicURL,
 			MachineName:   firstLabel(who.Node.ComputedName),
-			MachineOS:     who.Node.Hostinfo.OS,
+			MachineOS:     who.Node.Hostinfo.OS(),
 			IP:            tailscaleIP(who),
 		}
 	}
@@ -178,8 +204,6 @@ func root(w http.ResponseWriter, r *http.Request) {
 
 // firstLabel s up until the first period, if any.
 func firstLabel(s string) string {
-	if i := strings.Index(s, "."); i != -1 {
-		return s[:i]
-	}
+	s, _, _ = strings.Cut(s, ".")
 	return s
 }

cmd/k8s-operator/manifests/authproxy-rbac.yaml

@@ -0,0 +1,24 @@
+# Copyright (c) Tailscale Inc & AUTHORS
+# SPDX-License-Identifier: BSD-3-Clause
+
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: tailscale-auth-proxy
+rules:
+- apiGroups: [""]
+  resources: ["users", "groups"]
+  verbs: ["impersonate"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: tailscale-auth-proxy
+subjects:
+- kind: ServiceAccount
+  name: operator
+  namespace: tailscale
+roleRef:
+  kind: ClusterRole
+  name: tailscale-auth-proxy
+  apiGroup: rbac.authorization.k8s.io

cmd/k8s-operator/manifests/operator.yaml

@@ -0,0 +1,156 @@
+# Copyright (c) Tailscale Inc & AUTHORS
+# SPDX-License-Identifier: BSD-3-Clause
+
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: tailscale
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: proxies
+  namespace: tailscale
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: proxies
+  namespace: tailscale
+rules:
+- apiGroups: [""]
+  resources: ["secrets"]
+  verbs: ["*"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: proxies
+  namespace: tailscale
+subjects:
+- kind: ServiceAccount
+  name: proxies
+  namespace: tailscale
+roleRef:
+  kind: Role
+  name: proxies
+  apiGroup: rbac.authorization.k8s.io
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: operator
+  namespace: tailscale
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: tailscale-operator
+rules:
+- apiGroups: [""]
+  resources: ["services", "services/status"]
+  verbs: ["*"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: tailscale-operator
+subjects:
+- kind: ServiceAccount
+  name: operator
+  namespace: tailscale
+roleRef:
+  kind: ClusterRole
+  name: tailscale-operator
+  apiGroup: rbac.authorization.k8s.io
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: operator
+  namespace: tailscale
+rules:
+- apiGroups: [""]
+  resources: ["secrets"]
+  verbs: ["*"]
+- apiGroups: ["apps"]
+  resources: ["statefulsets"]
+  verbs: ["*"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: operator
+  namespace: tailscale
+subjects:
+- kind: ServiceAccount
+  name: operator
+  namespace: tailscale
+roleRef:
+  kind: Role
+  name: operator
+  apiGroup: rbac.authorization.k8s.io
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: operator-oauth
+  namespace: tailscale
+stringData:
+  client_id: # SET CLIENT ID HERE
+  client_secret: # SET CLIENT SECRET HERE
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: operator
+  namespace: tailscale
+spec:
+  replicas: 1
+  strategy:
+    type: Recreate
+  selector:
+    matchLabels:
+      app: operator
+  template:
+    metadata:
+      labels:
+        app: operator
+    spec:
+      serviceAccountName: operator
+      volumes:
+      - name: oauth
+        secret:
+          secretName: operator-oauth
+      containers:
+        - name: operator
+          image: tailscale/k8s-operator:unstable
+          resources:
+            requests:
+              cpu: 500m
+              memory: 100Mi
+          env:
+            - name: OPERATOR_HOSTNAME
+              value: tailscale-operator
+            - name: OPERATOR_SECRET
+              value: operator
+            - name: OPERATOR_LOGGING
+              value: info
+            - name: OPERATOR_NAMESPACE
+              valueFrom:
+                fieldRef:
+                  fieldPath: metadata.namespace
+            - name: CLIENT_ID_FILE
+              value: /oauth/client_id
+            - name: CLIENT_SECRET_FILE
+              value: /oauth/client_secret
+            - name: PROXY_IMAGE
+              value: tailscale/tailscale:unstable
+            - name: PROXY_TAGS
+              value: tag:k8s
+            - name: AUTH_PROXY
+              value: "false"
+          volumeMounts:
+          - name: oauth
+            mountPath: /oauth
+            readOnly: true

cmd/k8s-operator/manifests/proxy.yaml

@@ -0,0 +1,37 @@
+# This file is not a complete manifest, it's a skeleton that the operator embeds
+# at build time and then uses to construct Tailscale proxy pods.
+apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+spec:
+  replicas: 1
+  template:
+    metadata:
+      deletionGracePeriodSeconds: 10
+    spec:
+      serviceAccountName: proxies
+      initContainers:
+        - name: sysctler
+          image: busybox
+          securityContext:
+            privileged: true
+          command: ["/bin/sh"]
+          args:
+            - -c
+            - sysctl -w net.ipv4.ip_forward=1 net.ipv6.conf.all.forwarding=1
+      resources:
+        requests:
+          cpu: 1m
+          memory: 1Mi
+      containers:
+        - name: tailscale
+          imagePullPolicy: Always
+          env:
+            - name: TS_USERSPACE
+              value: "false"
+            - name: TS_AUTH_ONCE
+              value: "true"
+          securityContext:
+            capabilities:
+              add:
+                - NET_ADMIN

cmd/k8s-operator/operator.go

@@ -0,0 +1,752 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// tailscale-operator provides a way to expose services running in a Kubernetes
+// cluster to your Tailnet.
+package main
+
+import (
+	"context"
+	"crypto/tls"
+	_ "embed"
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/go-logr/zapr"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+	"golang.org/x/exp/slices"
+	"golang.org/x/oauth2/clientcredentials"
+	appsv1 "k8s.io/api/apps/v1"
+	corev1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/client-go/transport"
+	"sigs.k8s.io/controller-runtime/pkg/builder"
+	"sigs.k8s.io/controller-runtime/pkg/cache"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
+	"sigs.k8s.io/controller-runtime/pkg/handler"
+	logf "sigs.k8s.io/controller-runtime/pkg/log"
+	kzap "sigs.k8s.io/controller-runtime/pkg/log/zap"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+	"sigs.k8s.io/controller-runtime/pkg/manager/signals"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+	"sigs.k8s.io/yaml"
+	"tailscale.com/client/tailscale"
+	"tailscale.com/hostinfo"
+	"tailscale.com/ipn"
+	"tailscale.com/ipn/store/kubestore"
+	"tailscale.com/tsnet"
+	"tailscale.com/types/logger"
+	"tailscale.com/types/opt"
+	"tailscale.com/util/dnsname"
+	"tailscale.com/version"
+)
+
+func main() {
+	// Required to use our client API. We're fine with the instability since the
+	// client lives in the same repo as this code.
+	tailscale.I_Acknowledge_This_API_Is_Unstable = true
+
+	var (
+		hostname           = defaultEnv("OPERATOR_HOSTNAME", "tailscale-operator")
+		kubeSecret         = defaultEnv("OPERATOR_SECRET", "")
+		operatorTags       = defaultEnv("OPERATOR_INITIAL_TAGS", "tag:k8s-operator")
+		tsNamespace        = defaultEnv("OPERATOR_NAMESPACE", "")
+		tslogging          = defaultEnv("OPERATOR_LOGGING", "info")
+		clientIDPath       = defaultEnv("CLIENT_ID_FILE", "")
+		clientSecretPath   = defaultEnv("CLIENT_SECRET_FILE", "")
+		image              = defaultEnv("PROXY_IMAGE", "tailscale/tailscale:latest")
+		priorityClassName  = defaultEnv("PROXY_PRIORITY_CLASS_NAME", "")
+		tags               = defaultEnv("PROXY_TAGS", "tag:k8s")
+		shouldRunAuthProxy = defaultBool("AUTH_PROXY", false)
+	)
+
+	var opts []kzap.Opts
+	switch tslogging {
+	case "info":
+		opts = append(opts, kzap.Level(zapcore.InfoLevel))
+	case "debug":
+		opts = append(opts, kzap.Level(zapcore.DebugLevel))
+	case "dev":
+		opts = append(opts, kzap.UseDevMode(true), kzap.Level(zapcore.DebugLevel))
+	}
+	zlog := kzap.NewRaw(opts...).Sugar()
+	logf.SetLogger(zapr.NewLogger(zlog.Desugar()))
+	startlog := zlog.Named("startup")
+
+	if clientIDPath == "" || clientSecretPath == "" {
+		startlog.Fatalf("CLIENT_ID_FILE and CLIENT_SECRET_FILE must be set")
+	}
+	clientID, err := os.ReadFile(clientIDPath)
+	if err != nil {
+		startlog.Fatalf("reading client ID %q: %v", clientIDPath, err)
+	}
+	clientSecret, err := os.ReadFile(clientSecretPath)
+	if err != nil {
+		startlog.Fatalf("reading client secret %q: %v", clientSecretPath, err)
+	}
+	credentials := clientcredentials.Config{
+		ClientID:     string(clientID),
+		ClientSecret: string(clientSecret),
+		TokenURL:     "https://login.tailscale.com/api/v2/oauth/token",
+	}
+	tsClient := tailscale.NewClient("-", nil)
+	tsClient.HTTPClient = credentials.Client(context.Background())
+
+	if shouldRunAuthProxy {
+		hostinfo.SetApp("k8s-operator-proxy")
+	} else {
+		hostinfo.SetApp("k8s-operator")
+	}
+
+	s := &tsnet.Server{
+		Hostname: hostname,
+		Logf:     zlog.Named("tailscaled").Debugf,
+	}
+	if kubeSecret != "" {
+		st, err := kubestore.New(logger.Discard, kubeSecret)
+		if err != nil {
+			startlog.Fatalf("creating kube store: %v", err)
+		}
+		s.Store = st
+	}
+	if err := s.Start(); err != nil {
+		startlog.Fatalf("starting tailscale server: %v", err)
+	}
+	defer s.Close()
+	lc, err := s.LocalClient()
+	if err != nil {
+		startlog.Fatalf("getting local client: %v", err)
+	}
+
+	ctx := context.Background()
+	loginDone := false
+	machineAuthShown := false
+waitOnline:
+	for {
+		startlog.Debugf("querying tailscaled status")
+		st, err := lc.StatusWithoutPeers(ctx)
+		if err != nil {
+			startlog.Fatalf("getting status: %v", err)
+		}
+		switch st.BackendState {
+		case "Running":
+			break waitOnline
+		case "NeedsLogin":
+			if loginDone {
+				break
+			}
+			caps := tailscale.KeyCapabilities{
+				Devices: tailscale.KeyDeviceCapabilities{
+					Create: tailscale.KeyDeviceCreateCapabilities{
+						Reusable:      false,
+						Preauthorized: true,
+						Tags:          strings.Split(operatorTags, ","),
+					},
+				},
+			}
+			authkey, _, err := tsClient.CreateKey(ctx, caps)
+			if err != nil {
+				startlog.Fatalf("creating operator authkey: %v", err)
+			}
+			if err := lc.Start(ctx, ipn.Options{
+				AuthKey: authkey,
+			}); err != nil {
+				startlog.Fatalf("starting tailscale: %v", err)
+			}
+			if err := lc.StartLoginInteractive(ctx); err != nil {
+				startlog.Fatalf("starting login: %v", err)
+			}
+			startlog.Debugf("requested login by authkey")
+			loginDone = true
+		case "NeedsMachineAuth":
+			if !machineAuthShown {
+				startlog.Infof("Machine approval required, please visit the admin panel to approve")
+				machineAuthShown = true
+			}
+		default:
+			startlog.Debugf("waiting for tailscale to start: %v", st.BackendState)
+		}
+		time.Sleep(time.Second)
+	}
+
+	// For secrets and statefulsets, we only get permission to touch the objects
+	// in the controller's own namespace. This cannot be expressed by
+	// .Watches(...) below, instead you have to add a per-type field selector to
+	// the cache that sits a few layers below the builder stuff, which will
+	// implicitly filter what parts of the world the builder code gets to see at
+	// all.
+	nsFilter := cache.ByObject{
+		Field: client.InNamespace(tsNamespace).AsSelector(),
+	}
+	restConfig := config.GetConfigOrDie()
+	mgr, err := manager.New(restConfig, manager.Options{
+		Cache: cache.Options{
+			ByObject: map[client.Object]cache.ByObject{
+				&corev1.Secret{}:      nsFilter,
+				&appsv1.StatefulSet{}: nsFilter,
+			},
+		},
+	})
+	if err != nil {
+		startlog.Fatalf("could not create manager: %v", err)
+	}
+
+	sr := &ServiceReconciler{
+		Client:                 mgr.GetClient(),
+		tsClient:               tsClient,
+		defaultTags:            strings.Split(tags, ","),
+		operatorNamespace:      tsNamespace,
+		proxyImage:             image,
+		proxyPriorityClassName: priorityClassName,
+		logger:                 zlog.Named("service-reconciler"),
+	}
+
+	reconcileFilter := handler.EnqueueRequestsFromMapFunc(func(_ context.Context, o client.Object) []reconcile.Request {
+		ls := o.GetLabels()
+		if ls[LabelManaged] != "true" {
+			return nil
+		}
+		if ls[LabelParentType] != "svc" {
+			return nil
+		}
+		return []reconcile.Request{
+			{
+				NamespacedName: types.NamespacedName{
+					Namespace: ls[LabelParentNamespace],
+					Name:      ls[LabelParentName],
+				},
+			},
+		}
+	})
+	err = builder.
+		ControllerManagedBy(mgr).
+		For(&corev1.Service{}).
+		Watches(&appsv1.StatefulSet{}, reconcileFilter).
+		Watches(&corev1.Secret{}, reconcileFilter).
+		Complete(sr)
+	if err != nil {
+		startlog.Fatalf("could not create controller: %v", err)
+	}
+
+	startlog.Infof("Startup complete, operator running, version: %s", version.Long())
+	if shouldRunAuthProxy {
+		cfg, err := restConfig.TransportConfig()
+		if err != nil {
+			startlog.Fatalf("could not get rest.TransportConfig(): %v", err)
+		}
+
+		// Kubernetes uses SPDY for exec and port-forward, however SPDY is
+		// incompatible with HTTP/2; so disable HTTP/2 in the proxy.
+		tr := http.DefaultTransport.(*http.Transport).Clone()
+		tr.TLSClientConfig, err = transport.TLSConfigFor(cfg)
+		if err != nil {
+			startlog.Fatalf("could not get transport.TLSConfigFor(): %v", err)
+		}
+		tr.TLSNextProto = make(map[string]func(authority string, c *tls.Conn) http.RoundTripper)
+
+		rt, err := transport.HTTPWrappersForConfig(cfg, tr)
+		if err != nil {
+			startlog.Fatalf("could not get rest.TransportConfig(): %v", err)
+		}
+		go runAuthProxy(s, rt, zlog.Named("auth-proxy").Infof)
+	}
+	if err := mgr.Start(signals.SetupSignalHandler()); err != nil {
+		startlog.Fatalf("could not start manager: %v", err)
+	}
+}
+
+const (
+	LabelManaged         = "tailscale.com/managed"
+	LabelParentType      = "tailscale.com/parent-resource-type"
+	LabelParentName      = "tailscale.com/parent-resource"
+	LabelParentNamespace = "tailscale.com/parent-resource-ns"
+
+	FinalizerName = "tailscale.com/finalizer"
+
+	AnnotationExpose   = "tailscale.com/expose"
+	AnnotationTags     = "tailscale.com/tags"
+	AnnotationHostname = "tailscale.com/hostname"
+)
+
+// ServiceReconciler is a simple ControllerManagedBy example implementation.
+type ServiceReconciler struct {
+	client.Client
+	tsClient               tsClient
+	defaultTags            []string
+	operatorNamespace      string
+	proxyImage             string
+	proxyPriorityClassName string
+	logger                 *zap.SugaredLogger
+}
+
+type tsClient interface {
+	CreateKey(ctx context.Context, caps tailscale.KeyCapabilities) (string, *tailscale.Key, error)
+	DeleteDevice(ctx context.Context, id string) error
+}
+
+func childResourceLabels(parent *corev1.Service) map[string]string {
+	// You might wonder why we're using owner references, since they seem to be
+	// built for exactly this. Unfortunately, Kubernetes does not support
+	// cross-namespace ownership, by design. This means we cannot make the
+	// service being exposed the owner of the implementation details of the
+	// proxying. Instead, we have to do our own filtering and tracking with
+	// labels.
+	return map[string]string{
+		LabelManaged:         "true",
+		LabelParentName:      parent.GetName(),
+		LabelParentNamespace: parent.GetNamespace(),
+		LabelParentType:      "svc",
+	}
+}
+
+func (a *ServiceReconciler) Reconcile(ctx context.Context, req reconcile.Request) (_ reconcile.Result, err error) {
+	logger := a.logger.With("service-ns", req.Namespace, "service-name", req.Name)
+	logger.Debugf("starting reconcile")
+	defer logger.Debugf("reconcile finished")
+
+	svc := new(corev1.Service)
+	err = a.Get(ctx, req.NamespacedName, svc)
+	if apierrors.IsNotFound(err) {
+		// Request object not found, could have been deleted after reconcile request.
+		logger.Debugf("service not found, assuming it was deleted")
+		return reconcile.Result{}, nil
+	} else if err != nil {
+		return reconcile.Result{}, fmt.Errorf("failed to get svc: %w", err)
+	}
+	if !svc.DeletionTimestamp.IsZero() || !a.shouldExpose(svc) {
+		logger.Debugf("service is being deleted or should not be exposed, cleaning up")
+		return reconcile.Result{}, a.maybeCleanup(ctx, logger, svc)
+	}
+
+	return reconcile.Result{}, a.maybeProvision(ctx, logger, svc)
+}
+
+// maybeCleanup removes any existing resources related to serving svc over tailscale.
+//
+// This function is responsible for removing the finalizer from the service,
+// once all associated resources are gone.
+func (a *ServiceReconciler) maybeCleanup(ctx context.Context, logger *zap.SugaredLogger, svc *corev1.Service) error {
+	ix := slices.Index(svc.Finalizers, FinalizerName)
+	if ix < 0 {
+		logger.Debugf("no finalizer, nothing to do")
+		return nil
+	}
+
+	ml := childResourceLabels(svc)
+
+	// Need to delete the StatefulSet first, and delete it with foreground
+	// cascading deletion. That way, the pod that's writing to the Secret will
+	// stop running before we start looking at the Secret's contents, and
+	// assuming k8s ordering semantics don't mess with us, that should avoid
+	// tailscale device deletion races where we fail to notice a device that
+	// should be removed.
+	sts, err := getSingleObject[appsv1.StatefulSet](ctx, a.Client, a.operatorNamespace, ml)
+	if err != nil {
+		return fmt.Errorf("getting statefulset: %w", err)
+	}
+	if sts != nil {
+		if !sts.GetDeletionTimestamp().IsZero() {
+			// Deletion in progress, check again later. We'll get another
+			// notification when the deletion is complete.
+			logger.Debugf("waiting for statefulset %s/%s deletion", sts.GetNamespace(), sts.GetName())
+			return nil
+		}
+		err := a.DeleteAllOf(ctx, &appsv1.StatefulSet{}, client.InNamespace(a.operatorNamespace), client.MatchingLabels(ml), client.PropagationPolicy(metav1.DeletePropagationForeground))
+		if err != nil {
+			return fmt.Errorf("deleting statefulset: %w", err)
+		}
+		logger.Debugf("started deletion of statefulset %s/%s", sts.GetNamespace(), sts.GetName())
+		return nil
+	}
+
+	id, _, err := a.getDeviceInfo(ctx, svc)
+	if err != nil {
+		return fmt.Errorf("getting device info: %w", err)
+	}
+	if id != "" {
+		// TODO: handle case where the device is already deleted, but the secret
+		// is still around.
+		if err := a.tsClient.DeleteDevice(ctx, id); err != nil {
+			return fmt.Errorf("deleting device: %w", err)
+		}
+	}
+
+	types := []client.Object{
+		&corev1.Service{},
+		&corev1.Secret{},
+	}
+	for _, typ := range types {
+		if err := a.DeleteAllOf(ctx, typ, client.InNamespace(a.operatorNamespace), client.MatchingLabels(ml)); err != nil {
+			return err
+		}
+	}
+
+	svc.Finalizers = append(svc.Finalizers[:ix], svc.Finalizers[ix+1:]...)
+	if err := a.Update(ctx, svc); err != nil {
+		return fmt.Errorf("failed to remove finalizer: %w", err)
+	}
+
+	// Unlike most log entries in the reconcile loop, this will get printed
+	// exactly once at the very end of cleanup, because the final step of
+	// cleanup removes the tailscale finalizer, which will make all future
+	// reconciles exit early.
+	logger.Infof("unexposed service from tailnet")
+	return nil
+}
+
+// maybeProvision ensures that svc is exposed over tailscale, taking any actions
+// necessary to reach that state.
+//
+// This function adds a finalizer to svc, ensuring that we can handle orderly
+// deprovisioning later.
+func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.SugaredLogger, svc *corev1.Service) error {
+	hostname, err := nameForService(svc)
+	if err != nil {
+		return err
+	}
+
+	if !slices.Contains(svc.Finalizers, FinalizerName) {
+		// This log line is printed exactly once during initial provisioning,
+		// because once the finalizer is in place this block gets skipped. So,
+		// this is a nice place to tell the operator that the high level,
+		// multi-reconcile operation is underway.
+		logger.Infof("exposing service over tailscale")
+		svc.Finalizers = append(svc.Finalizers, FinalizerName)
+		if err := a.Update(ctx, svc); err != nil {
+			return fmt.Errorf("failed to add finalizer: %w", err)
+		}
+	}
+
+	// Do full reconcile.
+	hsvc, err := a.reconcileHeadlessService(ctx, logger, svc)
+	if err != nil {
+		return fmt.Errorf("failed to reconcile headless service: %w", err)
+	}
+
+	tags := a.defaultTags
+	if tstr, ok := svc.Annotations[AnnotationTags]; ok {
+		tags = strings.Split(tstr, ",")
+	}
+	secretName, err := a.createOrGetSecret(ctx, logger, svc, hsvc, tags)
+	if err != nil {
+		return fmt.Errorf("failed to create or get API key secret: %w", err)
+	}
+	_, err = a.reconcileSTS(ctx, logger, svc, hsvc, secretName, hostname)
+	if err != nil {
+		return fmt.Errorf("failed to reconcile statefulset: %w", err)
+	}
+
+	if !a.hasLoadBalancerClass(svc) {
+		logger.Debugf("service is not a LoadBalancer, so not updating ingress")
+		return nil
+	}
+
+	_, tsHost, err := a.getDeviceInfo(ctx, svc)
+	if err != nil {
+		return fmt.Errorf("failed to get device ID: %w", err)
+	}
+	if tsHost == "" {
+		logger.Debugf("no Tailscale hostname known yet, waiting for proxy pod to finish auth")
+		// No hostname yet. Wait for the proxy pod to auth.
+		svc.Status.LoadBalancer.Ingress = nil
+		if err := a.Status().Update(ctx, svc); err != nil {
+			return fmt.Errorf("failed to update service status: %w", err)
+		}
+		return nil
+	}
+
+	logger.Debugf("setting ingress hostname to %q", tsHost)
+	svc.Status.LoadBalancer.Ingress = []corev1.LoadBalancerIngress{
+		{
+			Hostname: tsHost,
+		},
+	}
+	if err := a.Status().Update(ctx, svc); err != nil {
+		return fmt.Errorf("failed to update service status: %w", err)
+	}
+	return nil
+}
+
+func (a *ServiceReconciler) shouldExpose(svc *corev1.Service) bool {
+	// Headless services can't be exposed, since there is no ClusterIP to
+	// forward to.
+	if svc.Spec.ClusterIP == "" || svc.Spec.ClusterIP == "None" {
+		return false
+	}
+
+	return a.hasLoadBalancerClass(svc) || a.hasAnnotation(svc)
+}
+
+func (a *ServiceReconciler) hasLoadBalancerClass(svc *corev1.Service) bool {
+	return svc != nil &&
+		svc.Spec.Type == corev1.ServiceTypeLoadBalancer &&
+		svc.Spec.LoadBalancerClass != nil &&
+		*svc.Spec.LoadBalancerClass == "tailscale"
+}
+
+func (a *ServiceReconciler) hasAnnotation(svc *corev1.Service) bool {
+	return svc != nil &&
+		svc.Annotations[AnnotationExpose] == "true"
+}
+
+func (a *ServiceReconciler) reconcileHeadlessService(ctx context.Context, logger *zap.SugaredLogger, svc *corev1.Service) (*corev1.Service, error) {
+	hsvc := &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			GenerateName: "ts-" + svc.Name + "-",
+			Namespace:    a.operatorNamespace,
+			Labels:       childResourceLabels(svc),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "None",
+			Selector: map[string]string{
+				"app": string(svc.UID),
+			},
+		},
+	}
+	logger.Debugf("reconciling headless service for StatefulSet")
+	return createOrUpdate(ctx, a.Client, a.operatorNamespace, hsvc, func(svc *corev1.Service) { svc.Spec = hsvc.Spec })
+}
+
+func (a *ServiceReconciler) createOrGetSecret(ctx context.Context, logger *zap.SugaredLogger, svc, hsvc *corev1.Service, tags []string) (string, error) {
+	secret := &corev1.Secret{
+		ObjectMeta: metav1.ObjectMeta{
+			// Hardcode a -0 suffix so that in future, if we support
+			// multiple StatefulSet replicas, we can provision -N for
+			// those.
+			Name:      hsvc.Name + "-0",
+			Namespace: a.operatorNamespace,
+			Labels:    childResourceLabels(svc),
+		},
+	}
+	if err := a.Get(ctx, client.ObjectKeyFromObject(secret), secret); err == nil {
+		logger.Debugf("secret %s/%s already exists", secret.GetNamespace(), secret.GetName())
+		return secret.Name, nil
+	} else if !apierrors.IsNotFound(err) {
+		return "", err
+	}
+
+	// Secret doesn't exist yet, create one. Initially it contains
+	// only the Tailscale authkey, but once Tailscale starts it'll
+	// also store the daemon state.
+	sts, err := getSingleObject[appsv1.StatefulSet](ctx, a.Client, a.operatorNamespace, childResourceLabels(svc))
+	if err != nil {
+		return "", err
+	}
+	if sts != nil {
+		// StatefulSet exists, so we have already created the secret.
+		// If the secret is missing, they should delete the StatefulSet.
+		logger.Errorf("Tailscale proxy secret doesn't exist, but the corresponding StatefulSet %s/%s already does. Something is wrong, please delete the StatefulSet.", sts.GetNamespace(), sts.GetName())
+		return "", nil
+	}
+	// Create API Key secret which is going to be used by the statefulset
+	// to authenticate with Tailscale.
+	logger.Debugf("creating authkey for new tailscale proxy")
+	authKey, err := a.newAuthKey(ctx, tags)
+	if err != nil {
+		return "", err
+	}
+
+	secret.StringData = map[string]string{
+		"authkey": authKey,
+	}
+	if err := a.Create(ctx, secret); err != nil {
+		return "", err
+	}
+	return secret.Name, nil
+}
+
+func (a *ServiceReconciler) getDeviceInfo(ctx context.Context, svc *corev1.Service) (id, hostname string, err error) {
+	sec, err := getSingleObject[corev1.Secret](ctx, a.Client, a.operatorNamespace, childResourceLabels(svc))
+	if err != nil {
+		return "", "", err
+	}
+	if sec == nil {
+		return "", "", nil
+	}
+	id = string(sec.Data["device_id"])
+	if id == "" {
+		return "", "", nil
+	}
+	// Kubernetes chokes on well-formed FQDNs with the trailing dot, so we have
+	// to remove it.
+	hostname = strings.TrimSuffix(string(sec.Data["device_fqdn"]), ".")
+	if hostname == "" {
+		return "", "", nil
+	}
+	return id, hostname, nil
+}
+
+func (a *ServiceReconciler) newAuthKey(ctx context.Context, tags []string) (string, error) {
+	caps := tailscale.KeyCapabilities{
+		Devices: tailscale.KeyDeviceCapabilities{
+			Create: tailscale.KeyDeviceCreateCapabilities{
+				Reusable:      false,
+				Preauthorized: true,
+				Tags:          tags,
+			},
+		},
+	}
+
+	key, _, err := a.tsClient.CreateKey(ctx, caps)
+	if err != nil {
+		return "", err
+	}
+	return key, nil
+}
+
+//go:embed manifests/proxy.yaml
+var proxyYaml []byte
+
+func (a *ServiceReconciler) reconcileSTS(ctx context.Context, logger *zap.SugaredLogger, parentSvc, headlessSvc *corev1.Service, authKeySecret, hostname string) (*appsv1.StatefulSet, error) {
+	var ss appsv1.StatefulSet
+	if err := yaml.Unmarshal(proxyYaml, &ss); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal proxy spec: %w", err)
+	}
+	container := &ss.Spec.Template.Spec.Containers[0]
+	container.Image = a.proxyImage
+	container.Env = append(container.Env,
+		corev1.EnvVar{
+			Name:  "TS_DEST_IP",
+			Value: parentSvc.Spec.ClusterIP,
+		},
+		corev1.EnvVar{
+			Name:  "TS_KUBE_SECRET",
+			Value: authKeySecret,
+		},
+		corev1.EnvVar{
+			Name:  "TS_HOSTNAME",
+			Value: hostname,
+		})
+	ss.ObjectMeta = metav1.ObjectMeta{
+		Name:      headlessSvc.Name,
+		Namespace: a.operatorNamespace,
+		Labels:    childResourceLabels(parentSvc),
+	}
+	ss.Spec.ServiceName = headlessSvc.Name
+	ss.Spec.Selector = &metav1.LabelSelector{
+		MatchLabels: map[string]string{
+			"app": string(parentSvc.UID),
+		},
+	}
+	ss.Spec.Template.ObjectMeta.Labels = map[string]string{
+		"app": string(parentSvc.UID),
+	}
+	ss.Spec.Template.Spec.PriorityClassName = a.proxyPriorityClassName
+	logger.Debugf("reconciling statefulset %s/%s", ss.GetNamespace(), ss.GetName())
+	return createOrUpdate(ctx, a.Client, a.operatorNamespace, &ss, func(s *appsv1.StatefulSet) { s.Spec = ss.Spec })
+}
+
+// ptrObject is a type constraint for pointer types that implement
+// client.Object.
+type ptrObject[T any] interface {
+	client.Object
+	*T
+}
+
+// createOrUpdate adds obj to the k8s cluster, unless the object already exists,
+// in which case update is called to make changes to it. If update is nil, the
+// existing object is returned unmodified.
+//
+// obj is looked up by its Name and Namespace if Name is set, otherwise it's
+// looked up by labels.
+func createOrUpdate[T any, O ptrObject[T]](ctx context.Context, c client.Client, ns string, obj O, update func(O)) (O, error) {
+	var (
+		existing O
+		err      error
+	)
+	if obj.GetName() != "" {
+		existing = new(T)
+		existing.SetName(obj.GetName())
+		existing.SetNamespace(obj.GetNamespace())
+		err = c.Get(ctx, client.ObjectKeyFromObject(obj), existing)
+	} else {
+		existing, err = getSingleObject[T, O](ctx, c, ns, obj.GetLabels())
+	}
+	if err == nil && existing != nil {
+		if update != nil {
+			update(existing)
+			if err := c.Update(ctx, existing); err != nil {
+				return nil, err
+			}
+		}
+		return existing, nil
+	}
+	if err != nil && !apierrors.IsNotFound(err) {
+		return nil, fmt.Errorf("failed to get object: %w", err)
+	}
+	if err := c.Create(ctx, obj); err != nil {
+		return nil, err
+	}
+	return obj, nil
+}
+
+// getSingleObject searches for k8s objects of type T
+// (e.g. corev1.Service) with the given labels, and returns
+// it. Returns nil if no objects match the labels, and an error if
+// more than one object matches.
+func getSingleObject[T any, O ptrObject[T]](ctx context.Context, c client.Client, ns string, labels map[string]string) (O, error) {
+	ret := O(new(T))
+	kinds, _, err := c.Scheme().ObjectKinds(ret)
+	if err != nil {
+		return nil, err
+	}
+	if len(kinds) != 1 {
+		// TODO: the runtime package apparently has a "pick the best
+		// GVK" function somewhere that might be good enough?
+		return nil, fmt.Errorf("more than 1 GroupVersionKind for %T", ret)
+	}
+
+	gvk := kinds[0]
+	gvk.Kind += "List"
+	lst := unstructured.UnstructuredList{}
+	lst.SetGroupVersionKind(gvk)
+	if err := c.List(ctx, &lst, client.InNamespace(ns), client.MatchingLabels(labels)); err != nil {
+		return nil, err
+	}
+
+	if len(lst.Items) == 0 {
+		return nil, nil
+	}
+	if len(lst.Items) > 1 {
+		return nil, fmt.Errorf("found multiple matching %T objects", ret)
+	}
+	if err := c.Scheme().Convert(&lst.Items[0], ret, nil); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+func defaultBool(envName string, defVal bool) bool {
+	vs := os.Getenv(envName)
+	if vs == "" {
+		return defVal
+	}
+	v, _ := opt.Bool(vs).Get()
+	return v
+}
+
+func defaultEnv(envName, defVal string) string {
+	v := os.Getenv(envName)
+	if v == "" {
+		return defVal
+	}
+	return v
+}
+
+func nameForService(svc *corev1.Service) (string, error) {
+	if h, ok := svc.Annotations[AnnotationHostname]; ok {
+		if err := dnsname.ValidLabel(h); err != nil {
+			return "", fmt.Errorf("invalid Tailscale hostname %q: %w", h, err)
+		}
+		return h, nil
+	}
+	return svc.Namespace + "-" + svc.Name, nil
+}

cmd/k8s-operator/operator_test.go

@@ -0,0 +1,904 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"context"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"go.uber.org/zap"
+	appsv1 "k8s.io/api/apps/v1"
+	corev1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/fake"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+	"tailscale.com/client/tailscale"
+	"tailscale.com/types/ptr"
+)
+
+func TestLoadBalancerClass(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:            fc,
+		tsClient:          ft,
+		defaultTags:       []string{"tag:k8s"},
+		operatorNamespace: "operator-ns",
+		proxyImage:        "tailscale/tailscale",
+		logger:            zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP:         "10.20.30.40",
+			Type:              corev1.ServiceTypeLoadBalancer,
+			LoadBalancerClass: ptr.To("tailscale"),
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSecret(fullName))
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+
+	// Normally the Tailscale proxy pod would come up here and write its info
+	// into the secret. Simulate that, then verify reconcile again and verify
+	// that we get to the end.
+	mustUpdate(t, fc, "operator-ns", fullName, func(s *corev1.Secret) {
+		if s.Data == nil {
+			s.Data = map[string][]byte{}
+		}
+		s.Data["device_id"] = []byte("ts-id-1234")
+		s.Data["device_fqdn"] = []byte("tailscale.device.name.")
+	})
+	expectReconciled(t, sr, "default", "test")
+	want := &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP:         "10.20.30.40",
+			Type:              corev1.ServiceTypeLoadBalancer,
+			LoadBalancerClass: ptr.To("tailscale"),
+		},
+		Status: corev1.ServiceStatus{
+			LoadBalancer: corev1.LoadBalancerStatus{
+				Ingress: []corev1.LoadBalancerIngress{
+					{
+						Hostname: "tailscale.device.name",
+					},
+				},
+			},
+		},
+	}
+	expectEqual(t, fc, want)
+
+	// Turn the service back into a ClusterIP service, which should make the
+	// operator clean up.
+	mustUpdate(t, fc, "default", "test", func(s *corev1.Service) {
+		s.Spec.Type = corev1.ServiceTypeClusterIP
+		s.Spec.LoadBalancerClass = nil
+	})
+	mustUpdateStatus(t, fc, "default", "test", func(s *corev1.Service) {
+		// Fake client doesn't automatically delete the LoadBalancer status when
+		// changing away from the LoadBalancer type, we have to do
+		// controller-manager's work by hand.
+		s.Status = corev1.ServiceStatus{}
+	})
+	// synchronous StatefulSet deletion triggers a requeue. But, the StatefulSet
+	// didn't create any child resources since this is all faked, so the
+	// deletion goes through immediately.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	// The deletion triggers another reconcile, to finish the cleanup.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Service](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Secret](t, fc, "operator-ns", fullName)
+	want = &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			UID:       types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+}
+
+func TestAnnotations(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:            fc,
+		tsClient:          ft,
+		defaultTags:       []string{"tag:k8s"},
+		operatorNamespace: "operator-ns",
+		proxyImage:        "tailscale/tailscale",
+		logger:            zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose": "true",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSecret(fullName))
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+	want := &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose": "true",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+
+	// Turn the service back into a ClusterIP service, which should make the
+	// operator clean up.
+	mustUpdate(t, fc, "default", "test", func(s *corev1.Service) {
+		delete(s.ObjectMeta.Annotations, "tailscale.com/expose")
+	})
+	// synchronous StatefulSet deletion triggers a requeue. But, the StatefulSet
+	// didn't create any child resources since this is all faked, so the
+	// deletion goes through immediately.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	// Second time around, the rest of cleanup happens.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Service](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Secret](t, fc, "operator-ns", fullName)
+	want = &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			UID:       types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+}
+
+func TestAnnotationIntoLB(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:            fc,
+		tsClient:          ft,
+		defaultTags:       []string{"tag:k8s"},
+		operatorNamespace: "operator-ns",
+		proxyImage:        "tailscale/tailscale",
+		logger:            zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose": "true",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSecret(fullName))
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+
+	// Normally the Tailscale proxy pod would come up here and write its info
+	// into the secret. Simulate that, since it would have normally happened at
+	// this point and the LoadBalancer is going to expect this.
+	mustUpdate(t, fc, "operator-ns", fullName, func(s *corev1.Secret) {
+		if s.Data == nil {
+			s.Data = map[string][]byte{}
+		}
+		s.Data["device_id"] = []byte("ts-id-1234")
+		s.Data["device_fqdn"] = []byte("tailscale.device.name.")
+	})
+	expectReconciled(t, sr, "default", "test")
+	want := &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose": "true",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+
+	// Remove Tailscale's annotation, and at the same time convert the service
+	// into a tailscale LoadBalancer.
+	mustUpdate(t, fc, "default", "test", func(s *corev1.Service) {
+		delete(s.ObjectMeta.Annotations, "tailscale.com/expose")
+		s.Spec.Type = corev1.ServiceTypeLoadBalancer
+		s.Spec.LoadBalancerClass = ptr.To("tailscale")
+	})
+	expectReconciled(t, sr, "default", "test")
+	// None of the proxy machinery should have changed...
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+	// ... but the service should have a LoadBalancer status.
+
+	want = &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP:         "10.20.30.40",
+			Type:              corev1.ServiceTypeLoadBalancer,
+			LoadBalancerClass: ptr.To("tailscale"),
+		},
+		Status: corev1.ServiceStatus{
+			LoadBalancer: corev1.LoadBalancerStatus{
+				Ingress: []corev1.LoadBalancerIngress{
+					{
+						Hostname: "tailscale.device.name",
+					},
+				},
+			},
+		},
+	}
+	expectEqual(t, fc, want)
+}
+
+func TestLBIntoAnnotation(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:            fc,
+		tsClient:          ft,
+		defaultTags:       []string{"tag:k8s"},
+		operatorNamespace: "operator-ns",
+		proxyImage:        "tailscale/tailscale",
+		logger:            zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP:         "10.20.30.40",
+			Type:              corev1.ServiceTypeLoadBalancer,
+			LoadBalancerClass: ptr.To("tailscale"),
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSecret(fullName))
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+
+	// Normally the Tailscale proxy pod would come up here and write its info
+	// into the secret. Simulate that, then verify reconcile again and verify
+	// that we get to the end.
+	mustUpdate(t, fc, "operator-ns", fullName, func(s *corev1.Secret) {
+		if s.Data == nil {
+			s.Data = map[string][]byte{}
+		}
+		s.Data["device_id"] = []byte("ts-id-1234")
+		s.Data["device_fqdn"] = []byte("tailscale.device.name.")
+	})
+	expectReconciled(t, sr, "default", "test")
+	want := &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP:         "10.20.30.40",
+			Type:              corev1.ServiceTypeLoadBalancer,
+			LoadBalancerClass: ptr.To("tailscale"),
+		},
+		Status: corev1.ServiceStatus{
+			LoadBalancer: corev1.LoadBalancerStatus{
+				Ingress: []corev1.LoadBalancerIngress{
+					{
+						Hostname: "tailscale.device.name",
+					},
+				},
+			},
+		},
+	}
+	expectEqual(t, fc, want)
+
+	// Turn the service back into a ClusterIP service, but also add the
+	// tailscale annotation.
+	mustUpdate(t, fc, "default", "test", func(s *corev1.Service) {
+		s.ObjectMeta.Annotations = map[string]string{
+			"tailscale.com/expose": "true",
+		}
+		s.Spec.Type = corev1.ServiceTypeClusterIP
+		s.Spec.LoadBalancerClass = nil
+	})
+	mustUpdateStatus(t, fc, "default", "test", func(s *corev1.Service) {
+		// Fake client doesn't automatically delete the LoadBalancer status when
+		// changing away from the LoadBalancer type, we have to do
+		// controller-manager's work by hand.
+		s.Status = corev1.ServiceStatus{}
+	})
+	expectReconciled(t, sr, "default", "test")
+
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "default-test", ""))
+
+	want = &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			Annotations: map[string]string{
+				"tailscale.com/expose": "true",
+			},
+			UID: types.UID("1234-UID"),
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+}
+
+func TestCustomHostname(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:            fc,
+		tsClient:          ft,
+		defaultTags:       []string{"tag:k8s"},
+		operatorNamespace: "operator-ns",
+		proxyImage:        "tailscale/tailscale",
+		logger:            zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose":   "true",
+				"tailscale.com/hostname": "reindeer-flotilla",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSecret(fullName))
+	expectEqual(t, fc, expectedHeadlessService(shortName))
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "reindeer-flotilla", ""))
+	want := &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "test",
+			Namespace:  "default",
+			Finalizers: []string{"tailscale.com/finalizer"},
+			UID:        types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose":   "true",
+				"tailscale.com/hostname": "reindeer-flotilla",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+
+	// Turn the service back into a ClusterIP service, which should make the
+	// operator clean up.
+	mustUpdate(t, fc, "default", "test", func(s *corev1.Service) {
+		delete(s.ObjectMeta.Annotations, "tailscale.com/expose")
+	})
+	// synchronous StatefulSet deletion triggers a requeue. But, the StatefulSet
+	// didn't create any child resources since this is all faked, so the
+	// deletion goes through immediately.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	// Second time around, the rest of cleanup happens.
+	expectReconciled(t, sr, "default", "test")
+	expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Service](t, fc, "operator-ns", shortName)
+	expectMissing[corev1.Secret](t, fc, "operator-ns", fullName)
+	want = &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			UID:       types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/hostname": "reindeer-flotilla",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	}
+	expectEqual(t, fc, want)
+}
+
+func TestCustomPriorityClassName(t *testing.T) {
+	fc := fake.NewFakeClient()
+	ft := &fakeTSClient{}
+	zl, err := zap.NewDevelopment()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sr := &ServiceReconciler{
+		Client:                 fc,
+		tsClient:               ft,
+		defaultTags:            []string{"tag:k8s"},
+		operatorNamespace:      "operator-ns",
+		proxyImage:             "tailscale/tailscale",
+		proxyPriorityClassName: "tailscale-critical",
+		logger:                 zl.Sugar(),
+	}
+
+	// Create a service that we should manage, and check that the initial round
+	// of objects looks right.
+	mustCreate(t, fc, &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "test",
+			Namespace: "default",
+			// The apiserver is supposed to set the UID, but the fake client
+			// doesn't. So, set it explicitly because other code later depends
+			// on it being set.
+			UID: types.UID("1234-UID"),
+			Annotations: map[string]string{
+				"tailscale.com/expose":   "true",
+				"tailscale.com/hostname": "custom-priority-class-name",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			ClusterIP: "10.20.30.40",
+			Type:      corev1.ServiceTypeClusterIP,
+		},
+	})
+
+	expectReconciled(t, sr, "default", "test")
+
+	fullName, shortName := findGenName(t, fc, "default", "test")
+
+	expectEqual(t, fc, expectedSTS(shortName, fullName, "custom-priority-class-name", "tailscale-critical"))
+}
+
+func expectedSecret(name string) *corev1.Secret {
+	return &corev1.Secret{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Secret",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      name,
+			Namespace: "operator-ns",
+			Labels: map[string]string{
+				"tailscale.com/managed":              "true",
+				"tailscale.com/parent-resource":      "test",
+				"tailscale.com/parent-resource-ns":   "default",
+				"tailscale.com/parent-resource-type": "svc",
+			},
+		},
+		StringData: map[string]string{
+			"authkey": "secret-authkey",
+		},
+	}
+}
+
+func expectedHeadlessService(name string) *corev1.Service {
+	return &corev1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:         name,
+			GenerateName: "ts-test-",
+			Namespace:    "operator-ns",
+			Labels: map[string]string{
+				"tailscale.com/managed":              "true",
+				"tailscale.com/parent-resource":      "test",
+				"tailscale.com/parent-resource-ns":   "default",
+				"tailscale.com/parent-resource-type": "svc",
+			},
+		},
+		Spec: corev1.ServiceSpec{
+			Selector: map[string]string{
+				"app": "1234-UID",
+			},
+			ClusterIP: "None",
+		},
+	}
+}
+
+func expectedSTS(stsName, secretName, hostname, priorityClassName string) *appsv1.StatefulSet {
+	return &appsv1.StatefulSet{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "StatefulSet",
+			APIVersion: "apps/v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      stsName,
+			Namespace: "operator-ns",
+			Labels: map[string]string{
+				"tailscale.com/managed":              "true",
+				"tailscale.com/parent-resource":      "test",
+				"tailscale.com/parent-resource-ns":   "default",
+				"tailscale.com/parent-resource-type": "svc",
+			},
+		},
+		Spec: appsv1.StatefulSetSpec{
+			Replicas: ptr.To[int32](1),
+			Selector: &metav1.LabelSelector{
+				MatchLabels: map[string]string{"app": "1234-UID"},
+			},
+			ServiceName: stsName,
+			Template: corev1.PodTemplateSpec{
+				ObjectMeta: metav1.ObjectMeta{
+					DeletionGracePeriodSeconds: ptr.To[int64](10),
+					Labels:                     map[string]string{"app": "1234-UID"},
+				},
+				Spec: corev1.PodSpec{
+					ServiceAccountName: "proxies",
+					PriorityClassName:  priorityClassName,
+					InitContainers: []corev1.Container{
+						{
+							Name:    "sysctler",
+							Image:   "busybox",
+							Command: []string{"/bin/sh"},
+							Args:    []string{"-c", "sysctl -w net.ipv4.ip_forward=1 net.ipv6.conf.all.forwarding=1"},
+							SecurityContext: &corev1.SecurityContext{
+								Privileged: ptr.To(true),
+							},
+						},
+					},
+					Containers: []corev1.Container{
+						{
+							Name:  "tailscale",
+							Image: "tailscale/tailscale",
+							Env: []corev1.EnvVar{
+								{Name: "TS_USERSPACE", Value: "false"},
+								{Name: "TS_AUTH_ONCE", Value: "true"},
+								{Name: "TS_DEST_IP", Value: "10.20.30.40"},
+								{Name: "TS_KUBE_SECRET", Value: secretName},
+								{Name: "TS_HOSTNAME", Value: hostname},
+							},
+							SecurityContext: &corev1.SecurityContext{
+								Capabilities: &corev1.Capabilities{
+									Add: []corev1.Capability{"NET_ADMIN"},
+								},
+							},
+							ImagePullPolicy: "Always",
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
+func findGenName(t *testing.T, client client.Client, ns, name string) (full, noSuffix string) {
+	t.Helper()
+	labels := map[string]string{
+		LabelManaged:         "true",
+		LabelParentName:      name,
+		LabelParentNamespace: ns,
+		LabelParentType:      "svc",
+	}
+	s, err := getSingleObject[corev1.Secret](context.Background(), client, "operator-ns", labels)
+	if err != nil {
+		t.Fatalf("finding secret for %q: %v", name, err)
+	}
+	return s.GetName(), strings.TrimSuffix(s.GetName(), "-0")
+}
+
+func mustCreate(t *testing.T, client client.Client, obj client.Object) {
+	t.Helper()
+	if err := client.Create(context.Background(), obj); err != nil {
+		t.Fatalf("creating %q: %v", obj.GetName(), err)
+	}
+}
+
+func mustUpdate[T any, O ptrObject[T]](t *testing.T, client client.Client, ns, name string, update func(O)) {
+	t.Helper()
+	obj := O(new(T))
+	if err := client.Get(context.Background(), types.NamespacedName{
+		Name:      name,
+		Namespace: ns,
+	}, obj); err != nil {
+		t.Fatalf("getting %q: %v", name, err)
+	}
+	update(obj)
+	if err := client.Update(context.Background(), obj); err != nil {
+		t.Fatalf("updating %q: %v", name, err)
+	}
+}
+
+func mustUpdateStatus[T any, O ptrObject[T]](t *testing.T, client client.Client, ns, name string, update func(O)) {
+	t.Helper()
+	obj := O(new(T))
+	if err := client.Get(context.Background(), types.NamespacedName{
+		Name:      name,
+		Namespace: ns,
+	}, obj); err != nil {
+		t.Fatalf("getting %q: %v", name, err)
+	}
+	update(obj)
+	if err := client.Status().Update(context.Background(), obj); err != nil {
+		t.Fatalf("updating %q: %v", name, err)
+	}
+}
+
+func expectEqual[T any, O ptrObject[T]](t *testing.T, client client.Client, want O) {
+	t.Helper()
+	got := O(new(T))
+	if err := client.Get(context.Background(), types.NamespacedName{
+		Name:      want.GetName(),
+		Namespace: want.GetNamespace(),
+	}, got); err != nil {
+		t.Fatalf("getting %q: %v", want.GetName(), err)
+	}
+	// The resource version changes eagerly whenever the operator does even a
+	// no-op update. Asserting a specific value leads to overly brittle tests,
+	// so just remove it from both got and want.
+	got.SetResourceVersion("")
+	want.SetResourceVersion("")
+	if diff := cmp.Diff(got, want); diff != "" {
+		t.Fatalf("unexpected object (-got +want):\n%s", diff)
+	}
+}
+
+func expectMissing[T any, O ptrObject[T]](t *testing.T, client client.Client, ns, name string) {
+	t.Helper()
+	obj := O(new(T))
+	if err := client.Get(context.Background(), types.NamespacedName{
+		Name:      name,
+		Namespace: ns,
+	}, obj); !apierrors.IsNotFound(err) {
+		t.Fatalf("object %s/%s unexpectedly present, wanted missing", ns, name)
+	}
+}
+
+func expectReconciled(t *testing.T, sr *ServiceReconciler, ns, name string) {
+	t.Helper()
+	req := reconcile.Request{
+		NamespacedName: types.NamespacedName{
+			Name:      name,
+			Namespace: ns,
+		},
+	}
+	res, err := sr.Reconcile(context.Background(), req)
+	if err != nil {
+		t.Fatalf("Reconcile: unexpected error: %v", err)
+	}
+	if res.Requeue {
+		t.Fatalf("unexpected immediate requeue")
+	}
+	if res.RequeueAfter != 0 {
+		t.Fatalf("unexpected timed requeue (%v)", res.RequeueAfter)
+	}
+}
+
+func expectRequeue(t *testing.T, sr *ServiceReconciler, ns, name string) {
+	t.Helper()
+	req := reconcile.Request{
+		NamespacedName: types.NamespacedName{
+			Name:      name,
+			Namespace: ns,
+		},
+	}
+	res, err := sr.Reconcile(context.Background(), req)
+	if err != nil {
+		t.Fatalf("Reconcile: unexpected error: %v", err)
+	}
+	if res.Requeue {
+		t.Fatalf("unexpected immediate requeue")
+	}
+	if res.RequeueAfter == 0 {
+		t.Fatalf("expected timed requeue, got success")
+	}
+}
+
+type fakeTSClient struct {
+	sync.Mutex
+	keyRequests []tailscale.KeyCapabilities
+	deleted     []string
+}
+
+func (c *fakeTSClient) CreateKey(ctx context.Context, caps tailscale.KeyCapabilities) (string, *tailscale.Key, error) {
+	c.Lock()
+	defer c.Unlock()
+	c.keyRequests = append(c.keyRequests, caps)
+	k := &tailscale.Key{
+		ID:           "key",
+		Created:      time.Now(),
+		Capabilities: caps,
+	}
+	return "secret-authkey", k, nil
+}
+
+func (c *fakeTSClient) DeleteDevice(ctx context.Context, deviceID string) error {
+	c.Lock()
+	defer c.Unlock()
+	c.deleted = append(c.deleted, deviceID)
+	return nil
+}
+
+func (c *fakeTSClient) KeyRequests() []tailscale.KeyCapabilities {
+	c.Lock()
+	defer c.Unlock()
+	return c.keyRequests
+}
+
+func (c *fakeTSClient) Deleted() []string {
+	c.Lock()
+	defer c.Unlock()
+	return c.deleted
+}

cmd/k8s-operator/proxy.go

@@ -0,0 +1,120 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package main
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"log"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"os"
+	"strings"
+
+	"tailscale.com/client/tailscale"
+	"tailscale.com/client/tailscale/apitype"
+	"tailscale.com/tsnet"
+	"tailscale.com/types/logger"
+)
+
+type whoIsKey struct{}
+
+// authProxy is an http.Handler that authenticates requests using the Tailscale
+// LocalAPI and then proxies them to the Kubernetes API.
+type authProxy struct {
+	logf logger.Logf
+	lc   *tailscale.LocalClient
+	rp   *httputil.ReverseProxy
+}
+
+func (h *authProxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	who, err := h.lc.WhoIs(r.Context(), r.RemoteAddr)
+	if err != nil {
+		h.logf("failed to authenticate caller: %v", err)
+		http.Error(w, "failed to authenticate caller", http.StatusInternalServerError)
+		return
+	}
+	r = r.WithContext(context.WithValue(r.Context(), whoIsKey{}, who))
+	h.rp.ServeHTTP(w, r)
+}
+
+// runAuthProxy runs an HTTP server that authenticates requests using the
+// Tailscale LocalAPI and then proxies them to the Kubernetes API.
+// It listens on :443 and uses the Tailscale HTTPS certificate.
+// s will be started if it is not already running.
+// rt is used to proxy requests to the Kubernetes API.
+//
+// It never returns.
+func runAuthProxy(s *tsnet.Server, rt http.RoundTripper, logf logger.Logf) {
+	ln, err := s.Listen("tcp", ":443")
+	if err != nil {
+		log.Fatalf("could not listen on :443: %v", err)
+	}
+	u, err := url.Parse(fmt.Sprintf("https://%s:%s", os.Getenv("KUBERNETES_SERVICE_HOST"), os.Getenv("KUBERNETES_SERVICE_PORT_HTTPS")))
+	if err != nil {
+		log.Fatalf("runAuthProxy: failed to parse URL %v", err)
+	}
+
+	lc, err := s.LocalClient()
+	if err != nil {
+		log.Fatalf("could not get local client: %v", err)
+	}
+	ap := &authProxy{
+		logf: logf,
+		lc:   lc,
+		rp: &httputil.ReverseProxy{
+			Director: func(r *http.Request) {
+				// We want to proxy to the Kubernetes API, but we want to use
+				// the caller's identity to do so. We do this by impersonating
+				// the caller using the Kubernetes User Impersonation feature:
+				// https://kubernetes.io/docs/reference/access-authn-authz/authentication/#user-impersonation
+
+				// Out of paranoia, remove all authentication headers that might
+				// have been set by the client.
+				r.Header.Del("Authorization")
+				r.Header.Del("Impersonate-Group")
+				r.Header.Del("Impersonate-User")
+				r.Header.Del("Impersonate-Uid")
+				for k := range r.Header {
+					if strings.HasPrefix(k, "Impersonate-Extra-") {
+						r.Header.Del(k)
+					}
+				}
+
+				// Now add the impersonation headers that we want.
+				who := r.Context().Value(whoIsKey{}).(*apitype.WhoIsResponse)
+				if who.Node.IsTagged() {
+					// Use the nodes FQDN as the username, and the nodes tags as the groups.
+					// "Impersonate-Group" requires "Impersonate-User" to be set.
+					r.Header.Set("Impersonate-User", strings.TrimSuffix(who.Node.Name, "."))
+					for _, tag := range who.Node.Tags {
+						r.Header.Add("Impersonate-Group", tag)
+					}
+				} else {
+					r.Header.Set("Impersonate-User", who.UserProfile.LoginName)
+				}
+
+				// Replace the URL with the Kubernetes APIServer.
+				r.URL.Scheme = u.Scheme
+				r.URL.Host = u.Host
+			},
+			Transport: rt,
+		},
+	}
+	hs := &http.Server{
+		// Kubernetes uses SPDY for exec and port-forward, however SPDY is
+		// incompatible with HTTP/2; so disable HTTP/2 in the proxy.
+		TLSConfig: &tls.Config{
+			GetCertificate: lc.GetCertificate,
+			NextProtos:     []string{"http/1.1"},
+		},
+		TLSNextProto: make(map[string]func(*http.Server, *tls.Conn, http.Handler)),
+		Handler:      ap,
+	}
+	if err := hs.ServeTLS(ln, "", ""); err != nil {
+		log.Fatalf("runAuthProxy: failed to serve %v", err)
+	}
+}

cmd/microproxy/microproxy.go

@@ -1,173 +0,0 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// microproxy proxies incoming HTTPS connections to another
-// destination. Instead of managing its own TLS certificates, it
-// borrows issued certificates and keys from an autocert directory.
-package main
-
-import (
-	"crypto/tls"
-	"encoding/json"
-	"flag"
-	"fmt"
-	"io"
-	"io/ioutil"
-	"log"
-	"net/http"
-	"net/http/httputil"
-	"net/url"
-	"path/filepath"
-	"strings"
-	"sync"
-	"time"
-
-	"tailscale.com/logpolicy"
-	"tailscale.com/tsweb"
-)
-
-var (
-	addr          = flag.String("addr", ":4430", "server address")
-	certdir       = flag.String("certdir", "", "directory to borrow LetsEncrypt certificates from")
-	hostname      = flag.String("hostname", "", "hostname to serve")
-	logCollection = flag.String("logcollection", "", "If non-empty, logtail collection to log to")
-	nodeExporter  = flag.String("node-exporter", "http://localhost:9100", "URL of the local prometheus node exporter")
-	goVarsURL     = flag.String("go-vars-url", "http://localhost:8383/debug/vars", "URL of a local Go server's /debug/vars endpoint")
-	insecure      = flag.Bool("insecure", false, "serve over http, for development")
-)
-
-func main() {
-	flag.Parse()
-
-	if *logCollection != "" {
-		logpolicy.New(*logCollection)
-	}
-
-	ne, err := url.Parse(*nodeExporter)
-	if err != nil {
-		log.Fatalf("Couldn't parse URL %q: %v", *nodeExporter, err)
-	}
-	proxy := httputil.NewSingleHostReverseProxy(ne)
-	proxy.FlushInterval = time.Second
-
-	if _, err = url.Parse(*goVarsURL); err != nil {
-		log.Fatalf("Couldn't parse URL %q: %v", *goVarsURL, err)
-	}
-
-	mux := http.NewServeMux()
-	tsweb.Debugger(mux) // registers /debug/*
-	mux.Handle("/metrics", tsweb.Protected(proxy))
-	mux.Handle("/varz", tsweb.Protected(tsweb.StdHandler(&goVarsHandler{*goVarsURL}, tsweb.HandlerOptions{
-		Quiet200s: true,
-		Logf:      log.Printf,
-	})))
-
-	ch := &certHolder{
-		hostname: *hostname,
-		path:     filepath.Join(*certdir, *hostname),
-	}
-
-	httpsrv := &http.Server{
-		Addr:    *addr,
-		Handler: mux,
-	}
-
-	if !*insecure {
-		httpsrv.TLSConfig = &tls.Config{GetCertificate: ch.GetCertificate}
-		err = httpsrv.ListenAndServeTLS("", "")
-	} else {
-		err = httpsrv.ListenAndServe()
-	}
-	if err != nil && err != http.ErrServerClosed {
-		log.Fatal(err)
-	}
-}
-
-type goVarsHandler struct {
-	url string
-}
-
-func promPrint(w io.Writer, prefix string, obj map[string]interface{}) {
-	for k, i := range obj {
-		if prefix != "" {
-			k = prefix + "_" + k
-		}
-		switch v := i.(type) {
-		case map[string]interface{}:
-			promPrint(w, k, v)
-		case float64:
-			const saveConfigReject = "control_save_config_rejected_"
-			const saveConfig = "control_save_config_"
-			switch {
-			case strings.HasPrefix(k, saveConfigReject):
-				fmt.Fprintf(w, "control_save_config_rejected{reason=%q} %f\n", k[len(saveConfigReject):], v)
-			case strings.HasPrefix(k, saveConfig):
-				fmt.Fprintf(w, "control_save_config{reason=%q} %f\n", k[len(saveConfig):], v)
-			default:
-				fmt.Fprintf(w, "%s %f\n", k, v)
-			}
-		default:
-			fmt.Fprintf(w, "# Skipping key %q, unhandled type %T\n", k, v)
-		}
-	}
-}
-
-func (h *goVarsHandler) ServeHTTPReturn(w http.ResponseWriter, r *http.Request) error {
-	resp, err := http.Get(h.url)
-	if err != nil {
-		return tsweb.Error(http.StatusInternalServerError, "fetch failed", err)
-	}
-	defer resp.Body.Close()
-	var mon map[string]interface{}
-	if err := json.NewDecoder(resp.Body).Decode(&mon); err != nil {
-		return tsweb.Error(http.StatusInternalServerError, "fetch failed", err)
-	}
-
-	w.WriteHeader(http.StatusOK)
-	promPrint(w, "", mon)
-	return nil
-}
-
-// certHolder loads and caches a TLS certificate from disk, reloading
-// it every hour.
-type certHolder struct {
-	hostname string // only hostname allowed in SNI
-	path     string // path of certificate+key combined PEM file
-
-	mu     sync.Mutex
-	cert   *tls.Certificate // cached parsed cert+key
-	loaded time.Time
-}
-
-func (c *certHolder) GetCertificate(ch *tls.ClientHelloInfo) (*tls.Certificate, error) {
-	if ch.ServerName != c.hostname {
-		return nil, fmt.Errorf("wrong client SNI %q", ch.ServerName)
-	}
-	c.mu.Lock()
-	defer c.mu.Unlock()
-	if time.Since(c.loaded) > time.Hour {
-		if err := c.loadLocked(); err != nil {
-			log.Printf("Reloading cert %q: %v", c.path, err)
-			// continue anyway, we might be able to serve off the stale cert.
-		}
-	}
-	return c.cert, nil
-}
-
-// load reloads the TLS certificate and key from disk. Caller must
-// hold mu.
-func (c *certHolder) loadLocked() error {
-	bs, err := ioutil.ReadFile(c.path)
-	if err != nil {
-		return fmt.Errorf("reading %q: %v", c.path, err)
-	}
-	cert, err := tls.X509KeyPair(bs, bs)
-	if err != nil {
-		return fmt.Errorf("parsing %q: %v", c.path, err)
-	}
-
-	c.cert = &cert
-	c.loaded = time.Now()
-	return nil
-}

cmd/mkmanifest/main.go

@@ -0,0 +1,51 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// The mkmanifest command is a simple helper utility to create a '.syso' file
+// that contains a Windows manifest file.
+package main
+
+import (
+	"log"
+	"os"
+
+	"github.com/tc-hib/winres"
+)
+
+func main() {
+	if len(os.Args) != 4 {
+		log.Fatalf("usage: %s arch manifest.xml output.syso", os.Args[0])
+	}
+
+	arch := winres.Arch(os.Args[1])
+	switch arch {
+	case winres.ArchAMD64, winres.ArchARM64, winres.ArchI386:
+	default:
+		log.Fatalf("unsupported arch: %s", arch)
+	}
+
+	manifest, err := os.ReadFile(os.Args[2])
+	if err != nil {
+		log.Fatalf("error reading manifest file %q: %v", os.Args[2], err)
+	}
+
+	out := os.Args[3]
+
+	// Start by creating an empty resource set
+	rs := winres.ResourceSet{}
+
+	// Add resources
+	rs.Set(winres.RT_MANIFEST, winres.ID(1), 0, manifest)
+
+	// Compile to a COFF object file
+	f, err := os.Create(out)
+	if err != nil {
+		log.Fatalf("error creating output file %q: %v", out, err)
+	}
+	if err := rs.WriteObject(f, arch); err != nil {
+		log.Fatalf("error writing object: %v", err)
+	}
+	if err := f.Close(); err != nil {
+		log.Fatalf("error writing output file %q: %v", out, err)
+	}
+}

cmd/mkpkg/main.go

@@ -1,11 +1,11 @@
-// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
 
 // mkpkg builds the Tailscale rpm and deb packages.
 package main
 
 import (
+	"flag"
 	"fmt"
 	"log"
 	"os"
@@ -14,7 +14,6 @@ import (
 	"github.com/goreleaser/nfpm"
 	_ "github.com/goreleaser/nfpm/deb"
 	_ "github.com/goreleaser/nfpm/rpm"
-	"github.com/pborman/getopt"
 )
 
 // parseFiles parses a comma-separated list of colon-separated pairs
@@ -44,19 +43,22 @@ func parseEmptyDirs(s string) []string {
 }
 
 func main() {
-	out := getopt.StringLong("out", 'o', "", "output file to write")
-	goarch := getopt.StringLong("arch", 'a', "amd64", "GOARCH this package is for")
-	pkgType := getopt.StringLong("type", 't', "deb", "type of package to build (deb or rpm)")
-	files := getopt.StringLong("files", 'F', "", "comma-separated list of files in src:dst form")
-	configFiles := getopt.StringLong("configs", 'C', "", "like --files, but for files marked as user-editable config files")
-	emptyDirs := getopt.StringLong("emptydirs", 'E', "", "comma-separated list of empty directories")
-	version := getopt.StringLong("version", 0, "0.0.0", "version of the package")
-	postinst := getopt.StringLong("postinst", 0, "", "debian postinst script path")
-	prerm := getopt.StringLong("prerm", 0, "", "debian prerm script path")
-	postrm := getopt.StringLong("postrm", 0, "", "debian postrm script path")
-	replaces := getopt.StringLong("replaces", 0, "", "package which this package replaces, if any")
-	depends := getopt.StringLong("depends", 0, "", "comma-separated list of packages this package depends on")
-	getopt.Parse()
+	out := flag.String("out", "", "output file to write")
+	name := flag.String("name", "tailscale", "package name")
+	description := flag.String("description", "The easiest, most secure, cross platform way to use WireGuard + oauth2 + 2FA/SSO", "package description")
+	goarch := flag.String("arch", "amd64", "GOARCH this package is for")
+	pkgType := flag.String("type", "deb", "type of package to build (deb or rpm)")
+	files := flag.String("files", "", "comma-separated list of files in src:dst form")
+	configFiles := flag.String("configs", "", "like --files, but for files marked as user-editable config files")
+	emptyDirs := flag.String("emptydirs", "", "comma-separated list of empty directories")
+	version := flag.String("version", "0.0.0", "version of the package")
+	postinst := flag.String("postinst", "", "debian postinst script path")
+	prerm := flag.String("prerm", "", "debian prerm script path")
+	postrm := flag.String("postrm", "", "debian postrm script path")
+	replaces := flag.String("replaces", "", "package which this package replaces, if any")
+	depends := flag.String("depends", "", "comma-separated list of packages this package depends on")
+	recommends := flag.String("recommends", "", "comma-separated list of packages this package recommends")
+	flag.Parse()
 
 	filesMap, err := parseFiles(*files)
 	if err != nil {
@@ -68,12 +70,12 @@ func main() {
 	}
 	emptyDirList := parseEmptyDirs(*emptyDirs)
 	info := nfpm.WithDefaults(&nfpm.Info{
-		Name:        "tailscale",
+		Name:        *name,
 		Arch:        *goarch,
 		Platform:    "linux",
 		Version:     *version,
 		Maintainer:  "Tailscale Inc <info@tailscale.com>",
-		Description: "The easiest, most secure, cross platform way to use WireGuard + oauth2 + 2FA/SSO",
+		Description: *description,
 		Homepage:    "https://www.tailscale.com",
 		License:     "MIT",
 		Overridables: nfpm.Overridables{
@@ -91,6 +93,9 @@ func main() {
 	if len(*depends) != 0 {
 		info.Overridables.Depends = strings.Split(*depends, ",")
 	}
+	if len(*recommends) != 0 {
+		info.Overridables.Recommends = strings.Split(*recommends, ",")
+	}
 	if *replaces != "" {
 		info.Overridables.Replaces = []string{*replaces}
 		info.Overridables.Conflicts = []string{*replaces}

cmd/mkversion/mkversion.go

@@ -0,0 +1,44 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// mkversion gets version info from git and outputs a bunch of shell variables
+// that get used elsewhere in the build system to embed version numbers into
+// binaries.
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"tailscale.com/tailcfg"
+	"tailscale.com/version/mkversion"
+)
+
+func main() {
+	prefix := ""
+	if len(os.Args) > 1 {
+		if os.Args[1] == "--export" {
+			prefix = "export "
+		} else {
+			fmt.Println("usage: mkversion [--export|-h|--help]")
+			os.Exit(1)
+		}
+	}
+
+	var b bytes.Buffer
+	io.WriteString(&b, mkversion.Info().String())
+	// Copyright and the client capability are not part of the version
+	// information, but similarly used in Xcode builds to embed in the metadata,
+	// thus generate them now.
+	copyright := fmt.Sprintf("Copyright © %d Tailscale Inc. All Rights Reserved.", time.Now().Year())
+	fmt.Fprintf(&b, "VERSION_COPYRIGHT=%q\n", copyright)
+	fmt.Fprintf(&b, "VERSION_CAPABILITY=%d\n", tailcfg.CurrentCapabilityVersion)
+	s := bufio.NewScanner(&b)
+	for s.Scan() {
+		fmt.Println(prefix + s.Text())
+	}
+}

cmd/nardump/README.md

@@ -0,0 +1,7 @@
+# nardump
+
+nardump is like nix-store --dump, but in Go, writing a NAR file (tar-like,
+but focused on being reproducible) to stdout or to a hash with the --sri flag.
+
+It lets us calculate the Nix sha256 in shell.nix without the person running
+git-pull-oss.sh having Nix available.

cmd/nardump/nardump.go

@@ -0,0 +1,184 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// nardump is like nix-store --dump, but in Go, writing a NAR
+// file (tar-like, but focused on being reproducible) to stdout
+// or to a hash with the --sri flag.
+//
+// It lets us calculate a Nix sha256 without the person running
+// git-pull-oss.sh having Nix available.
+package main
+
+// For the format, see:
+// See https://gist.github.com/jbeda/5c79d2b1434f0018d693
+
+import (
+	"bufio"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/binary"
+	"flag"
+	"fmt"
+	"io"
+	"io/fs"
+	"log"
+	"os"
+	"path"
+	"sort"
+)
+
+var sri = flag.Bool("sri", false, "print SRI")
+
+func main() {
+	flag.Parse()
+	if flag.NArg() != 1 {
+		log.Fatal("usage: nardump <dir>")
+	}
+	arg := flag.Arg(0)
+	if err := os.Chdir(arg); err != nil {
+		log.Fatal(err)
+	}
+	if *sri {
+		hash := sha256.New()
+		if err := writeNAR(hash, os.DirFS(".")); err != nil {
+			log.Fatal(err)
+		}
+		fmt.Printf("sha256-%s\n", base64.StdEncoding.EncodeToString(hash.Sum(nil)))
+		return
+	}
+	bw := bufio.NewWriter(os.Stdout)
+	if err := writeNAR(bw, os.DirFS(".")); err != nil {
+		log.Fatal(err)
+	}
+	bw.Flush()
+}
+
+// writeNARError is a sentinel panic type that's recovered by writeNAR
+// and converted into the wrapped error.
+type writeNARError struct{ err error }
+
+// narWriter writes NAR files.
+type narWriter struct {
+	w  io.Writer
+	fs fs.FS
+}
+
+// writeNAR writes a NAR file to w from the root of fs.
+func writeNAR(w io.Writer, fs fs.FS) (err error) {
+	defer func() {
+		if e := recover(); e != nil {
+			if we, ok := e.(writeNARError); ok {
+				err = we.err
+				return
+			}
+			panic(e)
+		}
+	}()
+	nw := &narWriter{w: w, fs: fs}
+	nw.str("nix-archive-1")
+	return nw.writeDir(".")
+}
+
+func (nw *narWriter) writeDir(dirPath string) error {
+	ents, err := fs.ReadDir(nw.fs, dirPath)
+	if err != nil {
+		return err
+	}
+	sort.Slice(ents, func(i, j int) bool {
+		return ents[i].Name() < ents[j].Name()
+	})
+	nw.str("(")
+	nw.str("type")
+	nw.str("directory")
+	for _, ent := range ents {
+		nw.str("entry")
+		nw.str("(")
+		nw.str("name")
+		nw.str(ent.Name())
+		nw.str("node")
+		mode := ent.Type()
+		sub := path.Join(dirPath, ent.Name())
+		var err error
+		switch {
+		case mode.IsRegular():
+			err = nw.writeRegular(sub)
+		case mode.IsDir():
+			err = nw.writeDir(sub)
+		default:
+			// TODO(bradfitz): symlink, but requires fighting io/fs a bit
+			// to get at Readlink or the osFS via fs. But for now
+			// we don't need symlinks because they're not in Go's archive.
+			return fmt.Errorf("unsupported file type %v at %q", sub, mode)
+		}
+		if err != nil {
+			return err
+		}
+		nw.str(")")
+	}
+	nw.str(")")
+	return nil
+}
+
+func (nw *narWriter) writeRegular(path string) error {
+	nw.str("(")
+	nw.str("type")
+	nw.str("regular")
+	fi, err := fs.Stat(nw.fs, path)
+	if err != nil {
+		return err
+	}
+	if fi.Mode()&0111 != 0 {
+		nw.str("executable")
+		nw.str("")
+	}
+	contents, err := fs.ReadFile(nw.fs, path)
+	if err != nil {
+		return err
+	}
+	nw.str("contents")
+	if err := writeBytes(nw.w, contents); err != nil {
+		return err
+	}
+	nw.str(")")
+	return nil
+}
+
+func (nw *narWriter) str(s string) {
+	if err := writeString(nw.w, s); err != nil {
+		panic(writeNARError{err})
+	}
+}
+
+func writeString(w io.Writer, s string) error {
+	var buf [8]byte
+	binary.LittleEndian.PutUint64(buf[:], uint64(len(s)))
+	if _, err := w.Write(buf[:]); err != nil {
+		return err
+	}
+	if _, err := io.WriteString(w, s); err != nil {
+		return err
+	}
+	return writePad(w, len(s))
+}
+
+func writeBytes(w io.Writer, b []byte) error {
+	var buf [8]byte
+	binary.LittleEndian.PutUint64(buf[:], uint64(len(b)))
+	if _, err := w.Write(buf[:]); err != nil {
+		return err
+	}
+	if _, err := w.Write(b); err != nil {
+		return err
+	}
+	return writePad(w, len(b))
+}
+
+func writePad(w io.Writer, n int) error {
+	pad := n % 8
+	if pad == 0 {
+		return nil
+	}
+	var zeroes [8]byte
+	_, err := w.Write(zeroes[:8-pad])
+	return err
+}

cmd/netlogfmt/main.go

@@ -0,0 +1,386 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// netlogfmt parses a stream of JSON log messages from stdin and
+// formats the network traffic logs produced by "tailscale.com/wgengine/netlog"
+// according to the schema in "tailscale.com/types/netlogtype.Message"
+// in a more humanly readable format.
+//
+// Example usage:
+//
+//	$ cat netlog.json | go run tailscale.com/cmd/netlogfmt
+//	=========================================================================================
+//	NodeID: n123456CNTRL
+//	Logged: 2022-10-13T20:23:10.165Z
+//	Window: 2022-10-13T20:23:09.644Z (5s)
+//	---------------------------------------------------  Tx[P/s]  Tx[B/s]  Rx[P/s]    Rx[B/s]
+//	VirtualTraffic:                                       16.80    1.64Ki   11.20      1.03Ki
+//	    TCP:    100.109.51.95:22 -> 100.85.80.41:42912    16.00    1.59Ki   10.40   1008.84
+//	    TCP: 100.109.51.95:21291 -> 100.107.177.2:53133    0.40   27.60      0.40     24.20
+//	    TCP: 100.109.51.95:21291 -> 100.107.177.2:53134    0.40   23.40      0.40     24.20
+//	PhysicalTraffic:                                      16.80    2.32Ki   11.20      1.48Ki
+//	                100.85.80.41 -> 192.168.0.101:41641   16.00    2.23Ki   10.40      1.40Ki
+//	               100.107.177.2 -> 192.168.0.100:41641    0.80   83.20      0.80     83.20
+//	=========================================================================================
+package main
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"net/http"
+	"net/netip"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/dsnet/try"
+	jsonv2 "github.com/go-json-experiment/json"
+	"golang.org/x/exp/maps"
+	"golang.org/x/exp/slices"
+	"tailscale.com/types/logid"
+	"tailscale.com/types/netlogtype"
+	"tailscale.com/util/must"
+)
+
+var (
+	resolveNames = flag.Bool("resolve-names", false, "convert tailscale IP addresses to hostnames; must also specify --api-key and --tailnet-id")
+	apiKey       = flag.String("api-key", "", "API key to query the Tailscale API with; see https://login.tailscale.com/admin/settings/keys")
+	tailnetName  = flag.String("tailnet-name", "", "tailnet domain name to lookup devices in; see https://login.tailscale.com/admin/settings/general")
+)
+
+var namesByAddr map[netip.Addr]string
+
+func main() {
+	flag.Parse()
+	if *resolveNames {
+		namesByAddr = mustMakeNamesByAddr()
+	}
+
+	// The logic handles a stream of arbitrary JSON.
+	// So long as a JSON object seems like a network log message,
+	// then this will unmarshal and print it.
+	if err := processStream(os.Stdin); err != nil {
+		if err == io.EOF {
+			return
+		}
+		log.Fatalf("processStream: %v", err)
+	}
+}
+
+func processStream(r io.Reader) (err error) {
+	defer try.Handle(&err)
+	dec := jsonv2.NewDecoder(os.Stdin)
+	for {
+		processValue(dec)
+	}
+}
+
+func processValue(dec *jsonv2.Decoder) {
+	switch dec.PeekKind() {
+	case '[':
+		processArray(dec)
+	case '{':
+		processObject(dec)
+	default:
+		try.E(dec.SkipValue())
+	}
+}
+
+func processArray(dec *jsonv2.Decoder) {
+	try.E1(dec.ReadToken()) // parse '['
+	for dec.PeekKind() != ']' {
+		processValue(dec)
+	}
+	try.E1(dec.ReadToken()) // parse ']'
+}
+
+func processObject(dec *jsonv2.Decoder) {
+	var hasTraffic bool
+	var rawMsg []byte
+	try.E1(dec.ReadToken()) // parse '{'
+	for dec.PeekKind() != '}' {
+		// Capture any members that could belong to a network log message.
+		switch name := try.E1(dec.ReadToken()); name.String() {
+		case "virtualTraffic", "subnetTraffic", "exitTraffic", "physicalTraffic":
+			hasTraffic = true
+			fallthrough
+		case "logtail", "nodeId", "logged", "start", "end":
+			if len(rawMsg) == 0 {
+				rawMsg = append(rawMsg, '{')
+			} else {
+				rawMsg = append(rawMsg[:len(rawMsg)-1], ',')
+			}
+			rawMsg = append(append(append(rawMsg, '"'), name.String()...), '"')
+			rawMsg = append(rawMsg, ':')
+			rawMsg = append(rawMsg, try.E1(dec.ReadValue())...)
+			rawMsg = append(rawMsg, '}')
+		default:
+			processValue(dec)
+		}
+	}
+	try.E1(dec.ReadToken()) // parse '}'
+
+	// If this appears to be a network log message, then unmarshal and print it.
+	if hasTraffic {
+		var msg message
+		try.E(jsonv2.Unmarshal(rawMsg, &msg))
+		printMessage(msg)
+	}
+}
+
+type message struct {
+	Logtail struct {
+		ID     logid.PublicID `json:"id"`
+		Logged time.Time      `json:"server_time"`
+	} `json:"logtail"`
+	Logged time.Time `json:"logged"`
+	netlogtype.Message
+}
+
+func printMessage(msg message) {
+	// Construct a table of network traffic per connection.
+	rows := [][7]string{{3: "Tx[P/s]", 4: "Tx[B/s]", 5: "Rx[P/s]", 6: "Rx[B/s]"}}
+	duration := msg.End.Sub(msg.Start)
+	addRows := func(heading string, traffic []netlogtype.ConnectionCounts) {
+		if len(traffic) == 0 {
+			return
+		}
+		slices.SortFunc(traffic, func(x, y netlogtype.ConnectionCounts) bool {
+			nx := x.TxPackets + x.TxBytes + x.RxPackets + x.RxBytes
+			ny := y.TxPackets + y.TxBytes + y.RxPackets + y.RxBytes
+			return nx > ny
+		})
+		var sum netlogtype.Counts
+		for _, cc := range traffic {
+			sum = sum.Add(cc.Counts)
+		}
+		rows = append(rows, [7]string{
+			0: heading + ":",
+			3: formatSI(float64(sum.TxPackets) / duration.Seconds()),
+			4: formatIEC(float64(sum.TxBytes) / duration.Seconds()),
+			5: formatSI(float64(sum.RxPackets) / duration.Seconds()),
+			6: formatIEC(float64(sum.RxBytes) / duration.Seconds()),
+		})
+		if len(traffic) == 1 && traffic[0].Connection.IsZero() {
+			return // this is already a summary counts
+		}
+		formatAddrPort := func(a netip.AddrPort) string {
+			if !a.IsValid() {
+				return ""
+			}
+			if name, ok := namesByAddr[a.Addr()]; ok {
+				if a.Port() == 0 {
+					return name
+				}
+				return name + ":" + strconv.Itoa(int(a.Port()))
+			}
+			if a.Port() == 0 {
+				return a.Addr().String()
+			}
+			return a.String()
+		}
+		for _, cc := range traffic {
+			row := [7]string{
+				0: "    ",
+				1: formatAddrPort(cc.Src),
+				2: formatAddrPort(cc.Dst),
+				3: formatSI(float64(cc.TxPackets) / duration.Seconds()),
+				4: formatIEC(float64(cc.TxBytes) / duration.Seconds()),
+				5: formatSI(float64(cc.RxPackets) / duration.Seconds()),
+				6: formatIEC(float64(cc.RxBytes) / duration.Seconds()),
+			}
+			if cc.Proto > 0 {
+				row[0] += cc.Proto.String() + ":"
+			}
+			rows = append(rows, row)
+		}
+	}
+	addRows("VirtualTraffic", msg.VirtualTraffic)
+	addRows("SubnetTraffic", msg.SubnetTraffic)
+	addRows("ExitTraffic", msg.ExitTraffic)
+	addRows("PhysicalTraffic", msg.PhysicalTraffic)
+
+	// Compute the maximum width of each field.
+	var maxWidths [7]int
+	for _, row := range rows {
+		for i, col := range row {
+			if maxWidths[i] < len(col) && !(i == 0 && !strings.HasPrefix(col, " ")) {
+				maxWidths[i] = len(col)
+			}
+		}
+	}
+	var maxSum int
+	for _, n := range maxWidths {
+		maxSum += n
+	}
+
+	// Output a table of network traffic per connection.
+	line := make([]byte, 0, maxSum+len(" ")+len(" -> ")+4*len("  "))
+	line = appendRepeatByte(line, '=', cap(line))
+	fmt.Println(string(line))
+	if !msg.Logtail.ID.IsZero() {
+		fmt.Printf("LogID:  %s\n", msg.Logtail.ID)
+	}
+	if msg.NodeID != "" {
+		fmt.Printf("NodeID: %s\n", msg.NodeID)
+	}
+	formatTime := func(t time.Time) string {
+		return t.In(time.Local).Format("2006-01-02 15:04:05.000")
+	}
+	switch {
+	case !msg.Logged.IsZero():
+		fmt.Printf("Logged: %s\n", formatTime(msg.Logged))
+	case !msg.Logtail.Logged.IsZero():
+		fmt.Printf("Logged: %s\n", formatTime(msg.Logtail.Logged))
+	}
+	fmt.Printf("Window: %s (%0.3fs)\n", formatTime(msg.Start), duration.Seconds())
+	for i, row := range rows {
+		line = line[:0]
+		isHeading := !strings.HasPrefix(row[0], " ")
+		for j, col := range row {
+			if isHeading && j == 0 {
+				col = "" // headings will be printed later
+			}
+			switch j {
+			case 0, 2: // left justified
+				line = append(line, col...)
+				line = appendRepeatByte(line, ' ', maxWidths[j]-len(col))
+			case 1, 3, 4, 5, 6: // right justified
+				line = appendRepeatByte(line, ' ', maxWidths[j]-len(col))
+				line = append(line, col...)
+			}
+			switch j {
+			case 0:
+				line = append(line, " "...)
+			case 1:
+				if row[1] == "" && row[2] == "" {
+					line = append(line, "    "...)
+				} else {
+					line = append(line, " -> "...)
+				}
+			case 2, 3, 4, 5:
+				line = append(line, "  "...)
+			}
+		}
+		switch {
+		case i == 0: // print dashed-line table heading
+			line = appendRepeatByte(line[:0], '-', maxWidths[0]+len(" ")+maxWidths[1]+len(" -> ")+maxWidths[2])[:cap(line)]
+		case isHeading:
+			copy(line[:], row[0])
+		}
+		fmt.Println(string(line))
+	}
+}
+
+func mustMakeNamesByAddr() map[netip.Addr]string {
+	switch {
+	case *apiKey == "":
+		log.Fatalf("--api-key must be specified with --resolve-names")
+	case *tailnetName == "":
+		log.Fatalf("--tailnet must be specified with --resolve-names")
+	}
+
+	// Query the Tailscale API for a list of devices in the tailnet.
+	const apiURL = "https://api.tailscale.com/api/v2"
+	req := must.Get(http.NewRequest("GET", apiURL+"/tailnet/"+*tailnetName+"/devices", nil))
+	req.Header.Add("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(*apiKey+":")))
+	resp := must.Get(http.DefaultClient.Do(req))
+	defer resp.Body.Close()
+	b := must.Get(io.ReadAll(resp.Body))
+	if resp.StatusCode != 200 {
+		log.Fatalf("http: %v: %s", http.StatusText(resp.StatusCode), b)
+	}
+
+	// Unmarshal the API response.
+	var m struct {
+		Devices []struct {
+			Name  string       `json:"name"`
+			Addrs []netip.Addr `json:"addresses"`
+		} `json:"devices"`
+	}
+	must.Do(json.Unmarshal(b, &m))
+
+	// Construct a unique mapping of Tailscale IP addresses to hostnames.
+	// For brevity, we start with the first segment of the name and
+	// use more segments until we find the shortest prefix that is unique
+	// for all names in the tailnet.
+	seen := make(map[string]bool)
+	namesByAddr := make(map[netip.Addr]string)
+retry:
+	for i := 0; i < 10; i++ {
+		maps.Clear(seen)
+		maps.Clear(namesByAddr)
+		for _, d := range m.Devices {
+			name := fieldPrefix(d.Name, i)
+			if seen[name] {
+				continue retry
+			}
+			seen[name] = true
+			for _, a := range d.Addrs {
+				namesByAddr[a] = name
+			}
+		}
+		return namesByAddr
+	}
+	panic("unable to produce unique mapping of address to names")
+}
+
+// fieldPrefix returns the first n number of dot-separated segments.
+//
+// Example:
+//
+//	fieldPrefix("foo.bar.baz", 0) returns ""
+//	fieldPrefix("foo.bar.baz", 1) returns "foo"
+//	fieldPrefix("foo.bar.baz", 2) returns "foo.bar"
+//	fieldPrefix("foo.bar.baz", 3) returns "foo.bar.baz"
+//	fieldPrefix("foo.bar.baz", 4) returns "foo.bar.baz"
+func fieldPrefix(s string, n int) string {
+	s0 := s
+	for i := 0; i < n && len(s) > 0; i++ {
+		if j := strings.IndexByte(s, '.'); j >= 0 {
+			s = s[j+1:]
+		} else {
+			s = ""
+		}
+	}
+	return strings.TrimSuffix(s0[:len(s0)-len(s)], ".")
+}
+
+func appendRepeatByte(b []byte, c byte, n int) []byte {
+	for i := 0; i < n; i++ {
+		b = append(b, c)
+	}
+	return b
+}
+
+func formatSI(n float64) string {
+	switch n := math.Abs(n); {
+	case n < 1e3:
+		return fmt.Sprintf("%0.2f ", n/(1e0))
+	case n < 1e6:
+		return fmt.Sprintf("%0.2fk", n/(1e3))
+	case n < 1e9:
+		return fmt.Sprintf("%0.2fM", n/(1e6))
+	default:
+		return fmt.Sprintf("%0.2fG", n/(1e9))
+	}
+}
+
+func formatIEC(n float64) string {
+	switch n := math.Abs(n); {
+	case n < 1<<10:
+		return fmt.Sprintf("%0.2f  ", n/(1<<0))
+	case n < 1<<20:
+		return fmt.Sprintf("%0.2fKi", n/(1<<10))
+	case n < 1<<30:
+		return fmt.Sprintf("%0.2fMi", n/(1<<20))
+	default:
+		return fmt.Sprintf("%0.2fGi", n/(1<<30))
+	}
+}

cmd/nginx-auth/.gitignore

@@ -0,0 +1,4 @@
+nga.sock
+*.deb
+*.rpm
+tailscale.nginx-auth

cmd/nginx-auth/README.md

@@ -0,0 +1,161 @@
+# nginx-auth
+
+[![status: experimental](https://img.shields.io/badge/status-experimental-blue)](https://tailscale.com/kb/1167/release-stages/#experimental)
+
+This is a tool that allows users to use Tailscale Whois authentication with
+NGINX as a reverse proxy. This allows users that already have a bunch of
+services hosted on an internal NGINX server to point those domains to the
+Tailscale IP of the NGINX server and then seamlessly use Tailscale for
+authentication.
+
+Many thanks to [@zrail](https://twitter.com/zrail/status/1511788463586222087) on
+Twitter for introducing the basic idea and offering some sample code. This
+program is based on that sample code with security enhancements. Namely:
+
+* This listens over a UNIX socket instead of a TCP socket, to prevent
+  leakage to the network
+* This uses systemd socket activation so that systemd owns the socket
+  and can then lock down the service to the bare minimum required to do
+  its job without having to worry about dropping permissions
+* This provides additional information in HTTP response headers that can
+  be useful for integrating with various services
+
+## Configuration
+
+In order to protect a service with this tool, do the following in the respective
+`server` block:
+
+Create an authentication location with the `internal` flag set:
+
+```nginx
+location /auth {
+  internal;
+
+  proxy_pass http://unix:/run/tailscale.nginx-auth.sock;
+  proxy_pass_request_body off;
+
+  proxy_set_header Host $http_host;
+  proxy_set_header Remote-Addr $remote_addr;
+  proxy_set_header Remote-Port $remote_port;
+  proxy_set_header Original-URI $request_uri;
+}
+```
+
+Then add the following to the `location /` block:
+
+```
+auth_request /auth;
+auth_request_set $auth_user $upstream_http_tailscale_user;
+auth_request_set $auth_name $upstream_http_tailscale_name;
+auth_request_set $auth_login $upstream_http_tailscale_login;
+auth_request_set $auth_tailnet $upstream_http_tailscale_tailnet;
+auth_request_set $auth_profile_picture $upstream_http_tailscale_profile_picture;
+
+proxy_set_header X-Webauth-User "$auth_user";
+proxy_set_header X-Webauth-Name "$auth_name";
+proxy_set_header X-Webauth-Login "$auth_login";
+proxy_set_header X-Webauth-Tailnet "$auth_tailnet";
+proxy_set_header X-Webauth-Profile-Picture "$auth_profile_picture";
+```
+
+When this configuration is used with a Go HTTP handler such as this:
+
+```go
+http.HandlerFunc(func (w http.ResponseWriter, r *http.Request) {
+	e := json.NewEncoder(w)
+	e.SetIndent("", "  ")
+	e.Encode(r.Header)
+})
+```
+
+You will get output like this:
+
+```json
+{
+  "Accept": [
+    "*/*"
+  ],
+  "Connection": [
+    "upgrade"
+  ],
+  "User-Agent": [
+    "curl/7.82.0"
+  ],
+  "X-Webauth-Login": [
+    "Xe"
+  ],
+  "X-Webauth-Name": [
+    "Xe Iaso"
+  ],
+  "X-Webauth-Profile-Picture": [
+    "https://avatars.githubusercontent.com/u/529003?v=4"
+  ],
+  "X-Webauth-Tailnet": [
+    "cetacean.org.github"
+  ]
+  "X-Webauth-User": [
+    "Xe@github"
+  ]
+}
+```
+
+## Headers
+
+The authentication service provides the following headers to decorate your
+proxied requests:
+
+| Header                      | Example Value                                                      | Description                                                                   |
+| :------                     | :--------------                                                    | :----------                                                                   |
+| `Tailscale-User`            | `azurediamond@hunter2.net`                                         | The Tailscale username the remote machine is logged in as in user@host form   |
+| `Tailscale-Login`           | `azurediamond`                                                     | The user portion of the Tailscale username the remote machine is logged in as |
+| `Tailscale-Name`            | `Azure Diamond`                                                    | The "real name" of the Tailscale user the machine is logged in as             |
+| `Tailscale-Profile-Picture` | `https://i.kym-cdn.com/photos/images/newsfeed/001/065/963/ae0.png` | The profile picture provided by the Identity Provider your tailnet uses       |
+| `Tailscale-Tailnet`          | `hunter2.net`                                       | The tailnet name                                                              |
+
+Most of the time you can set `X-Webauth-User` to the contents of the
+`Tailscale-User` header, but some services may not accept a username with an `@`
+symbol in it. If this is the case, set `X-Webauth-User` to the `Tailscale-Login`
+header.
+
+The `Tailscale-Tailnet` header can help you identify which tailnet the session
+is coming from. If you are using node sharing, this can help you make sure that
+you aren't giving administrative access to people outside your tailnet.
+
+### Allow Requests From Only One Tailnet
+
+If you want to prevent node sharing from allowing users to access a service, add
+the `Expected-Tailnet` header to your auth request:
+
+```nginx
+location /auth {
+  # ...
+  proxy_set_header Expected-Tailnet "tailnet012345.ts.net";
+}
+```
+
+If a user from a different tailnet tries to use that service, this will return a
+generic "forbidden" error page:
+
+```html
+<html>
+<head><title>403 Forbidden</title></head>
+<body>
+<center><h1>403 Forbidden</h1></center>
+<hr><center>nginx/1.18.0 (Ubuntu)</center>
+</body>
+</html>
+```
+
+You can get the tailnet name from [the admin panel](https://login.tailscale.com/admin/dns).
+
+## Building
+
+Install `cmd/mkpkg`:
+
+```
+cd .. && go install ./mkpkg
+```
+
+Then run `./mkdeb.sh`. It will emit a `.deb` and `.rpm` package for amd64
+machines (Linux uname flag: `x86_64`). You can add these to your deployment
+methods as you see fit.