quic-go experimentation

Signed-off-by: Percy Wegmann <percy@tailscale.com>

.github/workflows/codeql-analysis.yml

@@ -55,7 +55,7 @@ jobs:
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@aa578102511db1f4524ed59b8cc2bae4f6e88195 # v3.27.6
+      uses: github/codeql-action/init@4f3212b61783c3c68e8309a0f18a699764811cda # v3.27.1
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -66,7 +66,7 @@ jobs:
     # 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@aa578102511db1f4524ed59b8cc2bae4f6e88195 # v3.27.6
+      uses: github/codeql-action/autobuild@4f3212b61783c3c68e8309a0f18a699764811cda # v3.27.1
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 https://git.io/JvXDl
@@ -80,4 +80,4 @@ jobs:
     #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@aa578102511db1f4524ed59b8cc2bae4f6e88195 # v3.27.6
+      uses: github/codeql-action/analyze@4f3212b61783c3c68e8309a0f18a699764811cda # v3.27.1

.github/workflows/test.yml

@@ -80,7 +80,7 @@ jobs:
     - name: checkout
       uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
     - name: Restore Cache
-      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
       with:
         # Note: unlike the other setups, this is only grabbing the mod download
         # cache, rather than the whole mod directory, as the download cache
@@ -159,7 +159,7 @@ jobs:
         cache: false
 
     - name: Restore Cache
-      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
       with:
         # Note: unlike the other setups, this is only grabbing the mod download
         # cache, rather than the whole mod directory, as the download cache
@@ -260,7 +260,7 @@ jobs:
     - name: checkout
       uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
     - name: Restore Cache
-      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
       with:
         # Note: unlike the other setups, this is only grabbing the mod download
         # cache, rather than the whole mod directory, as the download cache
@@ -319,7 +319,7 @@ jobs:
     - name: checkout
       uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
     - name: Restore Cache
-      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
       with:
         # Note: unlike the other setups, this is only grabbing the mod download
         # cache, rather than the whole mod directory, as the download cache
@@ -367,7 +367,7 @@ jobs:
     - name: checkout
       uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
     - name: Restore Cache
-      uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4.2.0
+      uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
       with:
         # Note: unlike the other setups, this is only grabbing the mod download
         # cache, rather than the whole mod directory, as the download cache

Makefile

@@ -116,6 +116,7 @@ sshintegrationtest: ## Run the SSH integration tests in various Docker container
 	GOOS=linux GOARCH=amd64 ./tool/go build -o ssh/tailssh/testcontainers/tailscaled ./cmd/tailscaled && \
 	echo "Testing on ubuntu:focal" && docker build --build-arg="BASE=ubuntu:focal" -t ssh-ubuntu-focal ssh/tailssh/testcontainers && \
 	echo "Testing on ubuntu:jammy" && docker build --build-arg="BASE=ubuntu:jammy" -t ssh-ubuntu-jammy ssh/tailssh/testcontainers && \
+	echo "Testing on ubuntu:mantic" && docker build --build-arg="BASE=ubuntu:mantic" -t ssh-ubuntu-mantic ssh/tailssh/testcontainers && \
 	echo "Testing on ubuntu:noble" && docker build --build-arg="BASE=ubuntu:noble" -t ssh-ubuntu-noble ssh/tailssh/testcontainers && \
 	echo "Testing on alpine:latest" && docker build --build-arg="BASE=alpine:latest" -t ssh-alpine-latest ssh/tailssh/testcontainers
 

cmd/containerboot/kube.go

@@ -24,7 +24,6 @@ import (
 type kubeClient struct {
 	kubeclient.Client
 	stateSecret string
-	canPatch    bool // whether the client has permissions to patch Kubernetes Secrets
 }
 
 func newKubeClient(root string, stateSecret string) (*kubeClient, error) {

cmd/containerboot/main.go

@@ -331,10 +331,8 @@ authLoop:
 		if err := client.SetServeConfig(ctx, new(ipn.ServeConfig)); err != nil {
 			log.Fatalf("failed to unset serve config: %v", err)
 		}
-		if hasKubeStateStore(cfg) {
-			if err := kc.storeHTTPSEndpoint(ctx, ""); err != nil {
-				log.Fatalf("failed to update HTTPS endpoint in tailscale state: %v", err)
-			}
+		if err := kc.storeHTTPSEndpoint(ctx, ""); err != nil {
+			log.Fatalf("failed to update HTTPS endpoint in tailscale state: %v", err)
 		}
 	}
 

cmd/containerboot/main_test.go

@@ -31,7 +31,6 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"golang.org/x/sys/unix"
 	"tailscale.com/ipn"
-	"tailscale.com/kube/egressservices"
 	"tailscale.com/tailcfg"
 	"tailscale.com/tstest"
 	"tailscale.com/types/netmap"
@@ -58,16 +57,6 @@ func TestContainerBoot(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error unmarshaling tailscaled config: %v", err)
 	}
-	serveConf := ipn.ServeConfig{TCP: map[uint16]*ipn.TCPPortHandler{80: {HTTP: true}}}
-	serveConfBytes, err := json.Marshal(serveConf)
-	if err != nil {
-		t.Fatalf("error unmarshaling serve config: %v", err)
-	}
-	egressSvcsCfg := egressservices.Configs{"foo": {TailnetTarget: egressservices.TailnetTarget{FQDN: "foo.tailnetxyx.ts.net"}}}
-	egressSvcsCfgBytes, err := json.Marshal(egressSvcsCfg)
-	if err != nil {
-		t.Fatalf("error unmarshaling egress services config: %v", err)
-	}
 
 	dirs := []string{
 		"var/lib",
@@ -84,16 +73,14 @@ func TestContainerBoot(t *testing.T) {
 		}
 	}
 	files := map[string][]byte{
-		"usr/bin/tailscaled":                         fakeTailscaled,
-		"usr/bin/tailscale":                          fakeTailscale,
-		"usr/bin/iptables":                           fakeTailscale,
-		"usr/bin/ip6tables":                          fakeTailscale,
-		"dev/net/tun":                                []byte(""),
-		"proc/sys/net/ipv4/ip_forward":               []byte("0"),
-		"proc/sys/net/ipv6/conf/all/forwarding":      []byte("0"),
-		"etc/tailscaled/cap-95.hujson":               tailscaledConfBytes,
-		"etc/tailscaled/serve-config.json":           serveConfBytes,
-		"etc/tailscaled/egress-services-config.json": egressSvcsCfgBytes,
+		"usr/bin/tailscaled":                    fakeTailscaled,
+		"usr/bin/tailscale":                     fakeTailscale,
+		"usr/bin/iptables":                      fakeTailscale,
+		"usr/bin/ip6tables":                     fakeTailscale,
+		"dev/net/tun":                           []byte(""),
+		"proc/sys/net/ipv4/ip_forward":          []byte("0"),
+		"proc/sys/net/ipv6/conf/all/forwarding": []byte("0"),
+		"etc/tailscaled/cap-95.hujson":          tailscaledConfBytes,
 	}
 	resetFiles := func() {
 		for path, content := range files {
@@ -842,101 +829,6 @@ func TestContainerBoot(t *testing.T) {
 				},
 			},
 		},
-		{
-			Name: "serve_config_no_kube",
-			Env: map[string]string{
-				"TS_SERVE_CONFIG": filepath.Join(d, "etc/tailscaled/serve-config.json"),
-				"TS_AUTHKEY":      "tskey-key",
-			},
-			Phases: []phase{
-				{
-					WantCmds: []string{
-						"/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking",
-						"/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key",
-					},
-				},
-				{
-					Notify: runningNotify,
-				},
-			},
-		},
-		{
-			Name: "serve_config_kube",
-			Env: map[string]string{
-				"KUBERNETES_SERVICE_HOST":       kube.Host,
-				"KUBERNETES_SERVICE_PORT_HTTPS": kube.Port,
-				"TS_SERVE_CONFIG":               filepath.Join(d, "etc/tailscaled/serve-config.json"),
-			},
-			KubeSecret: map[string]string{
-				"authkey": "tskey-key",
-			},
-			Phases: []phase{
-				{
-					WantCmds: []string{
-						"/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking",
-						"/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key",
-					},
-					WantKubeSecret: map[string]string{
-						"authkey": "tskey-key",
-					},
-				},
-				{
-					Notify: runningNotify,
-					WantKubeSecret: map[string]string{
-						"authkey":          "tskey-key",
-						"device_fqdn":      "test-node.test.ts.net",
-						"device_id":        "myID",
-						"device_ips":       `["100.64.0.1"]`,
-						"https_endpoint":   "no-https",
-						"tailscale_capver": capver,
-					},
-				},
-			},
-		},
-		{
-			Name: "egress_svcs_config_kube",
-			Env: map[string]string{
-				"KUBERNETES_SERVICE_HOST":        kube.Host,
-				"KUBERNETES_SERVICE_PORT_HTTPS":  kube.Port,
-				"TS_EGRESS_SERVICES_CONFIG_PATH": filepath.Join(d, "etc/tailscaled/egress-services-config.json"),
-			},
-			KubeSecret: map[string]string{
-				"authkey": "tskey-key",
-			},
-			Phases: []phase{
-				{
-					WantCmds: []string{
-						"/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking",
-						"/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key",
-					},
-					WantKubeSecret: map[string]string{
-						"authkey": "tskey-key",
-					},
-				},
-				{
-					Notify: runningNotify,
-					WantKubeSecret: map[string]string{
-						"authkey":          "tskey-key",
-						"device_fqdn":      "test-node.test.ts.net",
-						"device_id":        "myID",
-						"device_ips":       `["100.64.0.1"]`,
-						"tailscale_capver": capver,
-					},
-				},
-			},
-		},
-		{
-			Name: "egress_svcs_config_no_kube",
-			Env: map[string]string{
-				"TS_EGRESS_SERVICES_CONFIG_PATH": filepath.Join(d, "etc/tailscaled/egress-services-config.json"),
-				"TS_AUTHKEY":                     "tskey-key",
-			},
-			Phases: []phase{
-				{
-					WantFatalLog: "TS_EGRESS_SERVICES_CONFIG_PATH is only supported for Tailscale running on Kubernetes",
-				},
-			},
-		},
 	}
 
 	for _, test := range tests {

cmd/containerboot/serve.go

@@ -72,10 +72,8 @@ func watchServeConfigChanges(ctx context.Context, path string, cdChanged <-chan
 		if err := updateServeConfig(ctx, sc, certDomain, lc); err != nil {
 			log.Fatalf("serve proxy: error updating serve config: %v", err)
 		}
-		if kc != nil && kc.canPatch {
-			if err := kc.storeHTTPSEndpoint(ctx, certDomain); err != nil {
-				log.Fatalf("serve proxy: error storing HTTPS endpoint: %v", err)
-			}
+		if err := kc.storeHTTPSEndpoint(ctx, certDomain); err != nil {
+			log.Fatalf("serve proxy: error storing HTTPS endpoint: %v", err)
 		}
 		prevServeConfig = sc
 	}

cmd/containerboot/settings.go

@@ -44,7 +44,6 @@ type settings struct {
 	DaemonExtraArgs               string
 	ExtraArgs                     string
 	InKubernetes                  bool
-	State                         string
 	UserspaceMode                 bool
 	StateDir                      string
 	AcceptDNS                     *bool
@@ -90,7 +89,6 @@ func configFromEnv() (*settings, error) {
 		DaemonExtraArgs:                       defaultEnv("TS_TAILSCALED_EXTRA_ARGS", ""),
 		ExtraArgs:                             defaultEnv("TS_EXTRA_ARGS", ""),
 		InKubernetes:                          os.Getenv("KUBERNETES_SERVICE_HOST") != "",
-		State:                                 defaultEnv("TS_STATE", ""),
 		UserspaceMode:                         defaultBool("TS_USERSPACE", true),
 		StateDir:                              defaultEnv("TS_STATE_DIR", ""),
 		AcceptDNS:                             defaultEnvBoolPointer("TS_ACCEPT_DNS"),
@@ -112,19 +110,6 @@ func configFromEnv() (*settings, error) {
 		EgressSvcsCfgPath:                     defaultEnv("TS_EGRESS_SERVICES_CONFIG_PATH", ""),
 		PodUID:                                defaultEnv("POD_UID", ""),
 	}
-
-	if cfg.State == "" {
-		if cfg.InKubernetes && cfg.KubeSecret != "" {
-			cfg.State = "kube:" + cfg.KubeSecret
-		} else {
-			cfg.State = "mem:"
-		}
-	}
-
-	if !strings.HasPrefix(cfg.State, "mem:") && !strings.HasPrefix(cfg.State, "kube:") && !strings.HasPrefix(cfg.State, "ssm:") {
-		return nil, fmt.Errorf("invalid TS_STATE value %q; must start with 'mem:', 'kube:', or 'ssm:'", cfg.State)
-	}
-
 	podIPs, ok := os.LookupEnv("POD_IPS")
 	if ok {
 		ips := strings.Split(podIPs, ",")
@@ -150,35 +135,6 @@ func configFromEnv() (*settings, error) {
 }
 
 func (s *settings) validate() error {
-
-	// Validate TS_STATE if set
-	if s.State != "" {
-		if !strings.HasPrefix(s.State, "mem:") && 
-		   !strings.HasPrefix(s.State, "kube:") && 
-		   !strings.HasPrefix(s.State, "ssm:") {
-			return fmt.Errorf("invalid TS_STATE value %q; must start with 'mem:', 'kube:', or 'ssm:'", s.State)
-		}
-
-		if strings.HasPrefix(s.State, "kube:") && !s.InKubernetes {
-			return fmt.Errorf("TS_STATE specifies Kubernetes state but the runtime environment is not Kubernetes")
-		}
-	}
-
-	// Check legacy settings and ensure no conflicts if TS_STATE is set
-	if s.State != "" {
-		if s.KubeSecret != "" {
-			log.Printf("[warning] TS_STATE is set; ignoring legacy TS_KUBE_SECRET")
-		}
-		if s.StateDir != "" {
-			log.Printf("[warning] TS_STATE is set; ignoring legacy TS_STATE_DIR")
-		}
-	} else {
-		// Fallback to legacy checks if TS_STATE is not set
-		if s.KubeSecret != "" && !s.InKubernetes {
-			return fmt.Errorf("TS_KUBE_SECRET is set but the runtime environment is not Kubernetes")
-		}
-	}
-
 	if s.TailscaledConfigFilePath != "" {
 		dir, file := path.Split(s.TailscaledConfigFilePath)
 		if _, err := os.Stat(dir); err != nil {
@@ -243,10 +199,6 @@ func (s *settings) validate() error {
 	if s.HealthCheckEnabled && s.HealthCheckAddrPort != "" {
 		return errors.New("TS_HEALTHCHECK_ADDR_PORT is deprecated and will be removed in 1.82.0, use TS_ENABLE_HEALTH_CHECK and optionally TS_LOCAL_ADDR_PORT")
 	}
-	if s.EgressSvcsCfgPath != "" && !(s.InKubernetes && s.KubeSecret != "") {
-		return errors.New("TS_EGRESS_SERVICES_CONFIG_PATH is only supported for Tailscale running on Kubernetes")
-	}
-	
 	return nil
 }
 
@@ -262,7 +214,6 @@ func (cfg *settings) setupKube(ctx context.Context, kc *kubeClient) error {
 		return fmt.Errorf("some Kubernetes permissions are missing, please check your RBAC configuration: %v", err)
 	}
 	cfg.KubernetesCanPatch = canPatch
-	kc.canPatch = canPatch
 
 	s, err := kc.GetSecret(ctx, cfg.KubeSecret)
 	if err != nil {

cmd/containerboot/tailscaled.go

@@ -62,22 +62,17 @@ func startTailscaled(ctx context.Context, cfg *settings) (*tailscale.LocalClient
 // tailscaledArgs uses cfg to construct the argv for tailscaled.
 func tailscaledArgs(cfg *settings) []string {
 	args := []string{"--socket=" + cfg.Socket}
-	if cfg.State != "" {
-		args = append(args, "--state="+cfg.State)
-	} else {
-		// Fallback logic for legacy state configuration
-		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")
+	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 {

cmd/k8s-operator/e2e/ingress_test.go

@@ -1,108 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package e2e
-
-import (
-	"context"
-	"fmt"
-	"net/http"
-	"testing"
-	"time"
-
-	corev1 "k8s.io/api/core/v1"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/util/wait"
-	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/client/config"
-	kube "tailscale.com/k8s-operator"
-	"tailscale.com/tstest"
-)
-
-// See [TestMain] for test requirements.
-func TestIngress(t *testing.T) {
-	if tsClient == nil {
-		t.Skip("TestIngress requires credentials for a tailscale client")
-	}
-
-	ctx := context.Background()
-	cfg := config.GetConfigOrDie()
-	cl, err := client.New(cfg, client.Options{})
-	if err != nil {
-		t.Fatal(err)
-	}
-	// Apply nginx
-	createAndCleanup(t, ctx, cl, &corev1.Pod{
-		ObjectMeta: metav1.ObjectMeta{
-			Name:      "nginx",
-			Namespace: "default",
-			Labels: map[string]string{
-				"app.kubernetes.io/name": "nginx",
-			},
-		},
-		Spec: corev1.PodSpec{
-			Containers: []corev1.Container{
-				{
-					Name:  "nginx",
-					Image: "nginx",
-				},
-			},
-		},
-	})
-	// Apply service to expose it as ingress
-	svc := &corev1.Service{
-		ObjectMeta: metav1.ObjectMeta{
-			Name:      "test-ingress",
-			Namespace: "default",
-			Annotations: map[string]string{
-				"tailscale.com/expose": "true",
-			},
-		},
-		Spec: corev1.ServiceSpec{
-			Selector: map[string]string{
-				"app.kubernetes.io/name": "nginx",
-			},
-			Ports: []corev1.ServicePort{
-				{
-					Name:     "http",
-					Protocol: "TCP",
-					Port:     80,
-				},
-			},
-		},
-	}
-	createAndCleanup(t, ctx, cl, svc)
-
-	// TODO: instead of timing out only when test times out, cancel context after 60s or so.
-	if err := wait.PollUntilContextCancel(ctx, time.Millisecond*100, true, func(ctx context.Context) (done bool, err error) {
-		maybeReadySvc := &corev1.Service{ObjectMeta: objectMeta("default", "test-ingress")}
-		if err := get(ctx, cl, maybeReadySvc); err != nil {
-			return false, err
-		}
-		isReady := kube.SvcIsReady(maybeReadySvc)
-		if isReady {
-			t.Log("Service is ready")
-		}
-		return isReady, nil
-	}); err != nil {
-		t.Fatalf("error waiting for the Service to become Ready: %v", err)
-	}
-
-	var resp *http.Response
-	if err := tstest.WaitFor(time.Second*60, func() error {
-		// TODO(tomhjp): Get the tailnet DNS name from the associated secret instead.
-		// If we are not the first tailnet node with the requested name, we'll get
-		// a -N suffix.
-		resp, err = tsClient.HTTPClient.Get(fmt.Sprintf("http://%s-%s:80", svc.Namespace, svc.Name))
-		if err != nil {
-			return err
-		}
-		return nil
-	}); err != nil {
-		t.Fatalf("error trying to reach service: %v", err)
-	}
-
-	if resp.StatusCode != http.StatusOK {
-		t.Fatalf("unexpected status: %v; response body s", resp.StatusCode)
-	}
-}

cmd/k8s-operator/e2e/main_test.go

@@ -1,194 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package e2e
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"log"
-	"os"
-	"slices"
-	"strings"
-	"testing"
-
-	"github.com/go-logr/zapr"
-	"github.com/tailscale/hujson"
-	"go.uber.org/zap/zapcore"
-	"golang.org/x/oauth2/clientcredentials"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"sigs.k8s.io/controller-runtime/pkg/client"
-	logf "sigs.k8s.io/controller-runtime/pkg/log"
-	kzap "sigs.k8s.io/controller-runtime/pkg/log/zap"
-	"tailscale.com/client/tailscale"
-)
-
-const (
-	e2eManagedComment = "// This is managed by the k8s-operator e2e tests"
-)
-
-var (
-	tsClient   *tailscale.Client
-	testGrants = map[string]string{
-		"test-proxy": `{
-			"src": ["tag:e2e-test-proxy"],
-			"dst": ["tag:k8s-operator"],
-			"app": {
-				"tailscale.com/cap/kubernetes": [{
-					"impersonate": {
-						"groups": ["ts:e2e-test-proxy"],
-					},
-				}],
-			},
-		}`,
-	}
-)
-
-// This test suite is currently not run in CI.
-// It requires some setup not handled by this code:
-// - Kubernetes cluster with tailscale operator installed
-// - Current kubeconfig context set to connect to that cluster (directly, no operator proxy)
-// - Operator installed with --set apiServerProxyConfig.mode="true"
-// - ACLs that define tag:e2e-test-proxy tag. TODO(tomhjp): Can maybe replace this prereq onwards with an API key
-// - OAuth client ID and secret in TS_API_CLIENT_ID and TS_API_CLIENT_SECRET env
-// - OAuth client must have auth_keys and policy_file write for tag:e2e-test-proxy tag
-func TestMain(m *testing.M) {
-	code, err := runTests(m)
-	if err != nil {
-		log.Fatal(err)
-	}
-	os.Exit(code)
-}
-
-func runTests(m *testing.M) (int, error) {
-	zlog := kzap.NewRaw([]kzap.Opts{kzap.UseDevMode(true), kzap.Level(zapcore.DebugLevel)}...).Sugar()
-	logf.SetLogger(zapr.NewLogger(zlog.Desugar()))
-	tailscale.I_Acknowledge_This_API_Is_Unstable = true
-
-	if clientID := os.Getenv("TS_API_CLIENT_ID"); clientID != "" {
-		cleanup, err := setupClientAndACLs()
-		if err != nil {
-			return 0, err
-		}
-		defer func() {
-			err = errors.Join(err, cleanup())
-		}()
-	}
-
-	return m.Run(), nil
-}
-
-func setupClientAndACLs() (cleanup func() error, _ error) {
-	ctx := context.Background()
-	credentials := clientcredentials.Config{
-		ClientID:     os.Getenv("TS_API_CLIENT_ID"),
-		ClientSecret: os.Getenv("TS_API_CLIENT_SECRET"),
-		TokenURL:     "https://login.tailscale.com/api/v2/oauth/token",
-		Scopes:       []string{"auth_keys", "policy_file"},
-	}
-	tsClient = tailscale.NewClient("-", nil)
-	tsClient.HTTPClient = credentials.Client(ctx)
-
-	if err := patchACLs(ctx, tsClient, func(acls *hujson.Value) {
-		for test, grant := range testGrants {
-			deleteTestGrants(test, acls)
-			addTestGrant(test, grant, acls)
-		}
-	}); err != nil {
-		return nil, err
-	}
-
-	return func() error {
-		return patchACLs(ctx, tsClient, func(acls *hujson.Value) {
-			for test := range testGrants {
-				deleteTestGrants(test, acls)
-			}
-		})
-	}, nil
-}
-
-func patchACLs(ctx context.Context, tsClient *tailscale.Client, patchFn func(*hujson.Value)) error {
-	acls, err := tsClient.ACLHuJSON(ctx)
-	if err != nil {
-		return err
-	}
-	hj, err := hujson.Parse([]byte(acls.ACL))
-	if err != nil {
-		return err
-	}
-
-	patchFn(&hj)
-
-	hj.Format()
-	acls.ACL = hj.String()
-	if _, err := tsClient.SetACLHuJSON(ctx, *acls, true); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func addTestGrant(test, grant string, acls *hujson.Value) error {
-	v, err := hujson.Parse([]byte(grant))
-	if err != nil {
-		return err
-	}
-
-	// Add the managed comment to the first line of the grant object contents.
-	v.Value.(*hujson.Object).Members[0].Name.BeforeExtra = hujson.Extra(fmt.Sprintf("%s: %s\n", e2eManagedComment, test))
-
-	if err := acls.Patch([]byte(fmt.Sprintf(`[{"op": "add", "path": "/grants/-", "value": %s}]`, v.String()))); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func deleteTestGrants(test string, acls *hujson.Value) error {
-	grants := acls.Find("/grants")
-
-	var patches []string
-	for i, g := range grants.Value.(*hujson.Array).Elements {
-		members := g.Value.(*hujson.Object).Members
-		if len(members) == 0 {
-			continue
-		}
-		comment := strings.TrimSpace(string(members[0].Name.BeforeExtra))
-		if name, found := strings.CutPrefix(comment, e2eManagedComment+": "); found && name == test {
-			patches = append(patches, fmt.Sprintf(`{"op": "remove", "path": "/grants/%d"}`, i))
-		}
-	}
-
-	// Remove in reverse order so we don't affect the found indices as we mutate.
-	slices.Reverse(patches)
-
-	if err := acls.Patch([]byte(fmt.Sprintf("[%s]", strings.Join(patches, ",")))); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func objectMeta(namespace, name string) metav1.ObjectMeta {
-	return metav1.ObjectMeta{
-		Namespace: namespace,
-		Name:      name,
-	}
-}
-
-func createAndCleanup(t *testing.T, ctx context.Context, cl client.Client, obj client.Object) {
-	t.Helper()
-	if err := cl.Create(ctx, obj); err != nil {
-		t.Fatal(err)
-	}
-	t.Cleanup(func() {
-		if err := cl.Delete(ctx, obj); err != nil {
-			t.Errorf("error cleaning up %s %s/%s: %s", obj.GetObjectKind().GroupVersionKind(), obj.GetNamespace(), obj.GetName(), err)
-		}
-	})
-}
-
-func get(ctx context.Context, cl client.Client, obj client.Object) error {
-	return cl.Get(ctx, client.ObjectKeyFromObject(obj), obj)
-}

cmd/k8s-operator/e2e/proxy_test.go

@@ -1,156 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package e2e
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"strings"
-	"testing"
-	"time"
-
-	corev1 "k8s.io/api/core/v1"
-	rbacv1 "k8s.io/api/rbac/v1"
-	apierrors "k8s.io/apimachinery/pkg/api/errors"
-	"k8s.io/client-go/rest"
-	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/client/config"
-	"tailscale.com/client/tailscale"
-	"tailscale.com/tsnet"
-	"tailscale.com/tstest"
-)
-
-// See [TestMain] for test requirements.
-func TestProxy(t *testing.T) {
-	if tsClient == nil {
-		t.Skip("TestProxy requires credentials for a tailscale client")
-	}
-
-	ctx := context.Background()
-	cfg := config.GetConfigOrDie()
-	cl, err := client.New(cfg, client.Options{})
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Create role and role binding to allow a group we'll impersonate to do stuff.
-	createAndCleanup(t, ctx, cl, &rbacv1.Role{
-		ObjectMeta: objectMeta("tailscale", "read-secrets"),
-		Rules: []rbacv1.PolicyRule{{
-			APIGroups: []string{""},
-			Verbs:     []string{"get"},
-			Resources: []string{"secrets"},
-		}},
-	})
-	createAndCleanup(t, ctx, cl, &rbacv1.RoleBinding{
-		ObjectMeta: objectMeta("tailscale", "read-secrets"),
-		Subjects: []rbacv1.Subject{{
-			Kind: "Group",
-			Name: "ts:e2e-test-proxy",
-		}},
-		RoleRef: rbacv1.RoleRef{
-			Kind: "Role",
-			Name: "read-secrets",
-		},
-	})
-
-	// Get operator host name from kube secret.
-	operatorSecret := corev1.Secret{
-		ObjectMeta: objectMeta("tailscale", "operator"),
-	}
-	if err := get(ctx, cl, &operatorSecret); err != nil {
-		t.Fatal(err)
-	}
-
-	// Connect to tailnet with test-specific tag so we can use the
-	// [testGrants] ACLs when connecting to the API server proxy
-	ts := tsnetServerWithTag(t, ctx, "tag:e2e-test-proxy")
-	proxyCfg := &rest.Config{
-		Host: fmt.Sprintf("https://%s:443", hostNameFromOperatorSecret(t, operatorSecret)),
-		Dial: ts.Dial,
-	}
-	proxyCl, err := client.New(proxyCfg, client.Options{})
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Expect success.
-	allowedSecret := corev1.Secret{
-		ObjectMeta: objectMeta("tailscale", "operator"),
-	}
-	// Wait for up to a minute the first time we use the proxy, to give it time
-	// to provision the TLS certs.
-	if err := tstest.WaitFor(time.Second*60, func() error {
-		return get(ctx, proxyCl, &allowedSecret)
-	}); err != nil {
-		t.Fatal(err)
-	}
-
-	// Expect forbidden.
-	forbiddenSecret := corev1.Secret{
-		ObjectMeta: objectMeta("default", "operator"),
-	}
-	if err := get(ctx, proxyCl, &forbiddenSecret); err == nil || !apierrors.IsForbidden(err) {
-		t.Fatalf("expected forbidden error fetching secret from default namespace: %s", err)
-	}
-}
-
-func tsnetServerWithTag(t *testing.T, ctx context.Context, tag string) *tsnet.Server {
-	caps := tailscale.KeyCapabilities{
-		Devices: tailscale.KeyDeviceCapabilities{
-			Create: tailscale.KeyDeviceCreateCapabilities{
-				Reusable:      false,
-				Preauthorized: true,
-				Ephemeral:     true,
-				Tags:          []string{tag},
-			},
-		},
-	}
-
-	authKey, authKeyMeta, err := tsClient.CreateKey(ctx, caps)
-	if err != nil {
-		t.Fatal(err)
-	}
-	t.Cleanup(func() {
-		if err := tsClient.DeleteKey(ctx, authKeyMeta.ID); err != nil {
-			t.Errorf("error deleting auth key: %s", err)
-		}
-	})
-
-	ts := &tsnet.Server{
-		Hostname:  "test-proxy",
-		Ephemeral: true,
-		Dir:       t.TempDir(),
-		AuthKey:   authKey,
-	}
-	_, err = ts.Up(ctx)
-	if err != nil {
-		t.Fatal(err)
-	}
-	t.Cleanup(func() {
-		if err := ts.Close(); err != nil {
-			t.Errorf("error shutting down tsnet.Server: %s", err)
-		}
-	})
-
-	return ts
-}
-
-func hostNameFromOperatorSecret(t *testing.T, s corev1.Secret) string {
-	profiles := map[string]any{}
-	if err := json.Unmarshal(s.Data["_profiles"], &profiles); err != nil {
-		t.Fatal(err)
-	}
-	key, ok := strings.CutPrefix(string(s.Data["_current-profile"]), "profile-")
-	if !ok {
-		t.Fatal(string(s.Data["_current-profile"]))
-	}
-	profile, ok := profiles[key]
-	if !ok {
-		t.Fatal(profiles)
-	}
-
-	return ((profile.(map[string]any))["Name"]).(string)
-}

derp/derp_client.go

@@ -216,24 +216,32 @@ func (c *Client) send(dstKey key.NodePublic, pkt []byte) (ret error) {
 		return fmt.Errorf("packet too big: %d", len(pkt))
 	}
 
+	fmt.Println("ZZZZ acquiring write lock")
 	c.wmu.Lock()
 	defer c.wmu.Unlock()
+	fmt.Println("ZZZZ acquired write lock")
 	if c.rate != nil {
 		pktLen := frameHeaderLen + key.NodePublicRawLen + len(pkt)
 		if !c.rate.AllowN(c.clock.Now(), pktLen) {
 			return nil // drop
 		}
 	}
+	fmt.Println("ZZZZ writing frame header")
 	if err := writeFrameHeader(c.bw, frameSendPacket, uint32(key.NodePublicRawLen+len(pkt))); err != nil {
 		return err
 	}
+	fmt.Println("ZZZZ writing destination key")
 	if _, err := c.bw.Write(dstKey.AppendTo(nil)); err != nil {
 		return err
 	}
+	fmt.Println("ZZZZ writing packet")
 	if _, err := c.bw.Write(pkt); err != nil {
 		return err
 	}
-	return c.bw.Flush()
+	fmt.Println("ZZZZ flushing buffer")
+	err := c.bw.Flush()
+	fmt.Println("ZZZZ flushed buffer")
+	return err
 }
 
 func (c *Client) ForwardPacket(srcKey, dstKey key.NodePublic, pkt []byte) (err error) {

derp/derp_server.go

@@ -84,19 +84,11 @@ func init() {
 }
 
 const (
-	defaultPerClientSendQueueDepth = 32 // default packets buffered for sending
-	writeTimeout                   = 2 * time.Second
-	privilegedWriteTimeout         = 30 * time.Second // for clients with the mesh key
+	perClientSendQueueDepth = 32000 // packets buffered for sending
+	writeTimeout            = 2 * time.Second
+	privilegedWriteTimeout  = 30 * time.Second // for clients with the mesh key
 )
 
-func getPerClientSendQueueDepth() int {
-	if v, ok := envknob.LookupInt("TS_DEBUG_DERP_PER_CLIENT_SEND_QUEUE_DEPTH"); ok {
-		return v
-	}
-
-	return defaultPerClientSendQueueDepth
-}
-
 // dupPolicy is a temporary (2021-08-30) mechanism to change the policy
 // of how duplicate connection for the same key are handled.
 type dupPolicy int8
@@ -198,9 +190,6 @@ type Server struct {
 	// maps from netip.AddrPort to a client's public key
 	keyOfAddr map[netip.AddrPort]key.NodePublic
 
-	// Sets the client send queue depth for the server.
-	perClientSendQueueDepth int
-
 	clock tstime.Clock
 }
 
@@ -388,8 +377,6 @@ func NewServer(privateKey key.NodePrivate, logf logger.Logf) *Server {
 
 	s.packetsDroppedTypeDisco = s.packetsDroppedType.Get("disco")
 	s.packetsDroppedTypeOther = s.packetsDroppedType.Get("other")
-
-	s.perClientSendQueueDepth = getPerClientSendQueueDepth()
 	return s
 }
 
@@ -862,8 +849,8 @@ func (s *Server) accept(ctx context.Context, nc Conn, brw *bufio.ReadWriter, rem
 		done:           ctx.Done(),
 		remoteIPPort:   remoteIPPort,
 		connectedAt:    s.clock.Now(),
-		sendQueue:      make(chan pkt, s.perClientSendQueueDepth),
-		discoSendQueue: make(chan pkt, s.perClientSendQueueDepth),
+		sendQueue:      make(chan pkt, perClientSendQueueDepth),
+		discoSendQueue: make(chan pkt, perClientSendQueueDepth),
 		sendPongCh:     make(chan [8]byte, 1),
 		peerGone:       make(chan peerGoneMsg),
 		canMesh:        s.isMeshPeer(clientInfo),

derp/derp_test.go

@@ -6,8 +6,9 @@ package derp
 import (
 	"bufio"
 	"bytes"
-	"cmp"
 	"context"
+	"crypto/rand"
+	"crypto/tls"
 	"crypto/x509"
 	"encoding/asn1"
 	"encoding/json"
@@ -20,15 +21,17 @@ import (
 	"os"
 	"reflect"
 	"strconv"
+	"strings"
 	"sync"
 	"testing"
 	"time"
 
-	qt "github.com/frankban/quicktest"
+	"github.com/quic-go/quic-go"
 	"go4.org/mem"
 	"golang.org/x/time/rate"
 	"tailscale.com/disco"
 	"tailscale.com/net/memnet"
+	"tailscale.com/syncs"
 	"tailscale.com/tstest"
 	"tailscale.com/types/key"
 	"tailscale.com/types/logger"
@@ -1379,70 +1382,250 @@ func BenchmarkConcurrentStreams(b *testing.B) {
 	})
 }
 
-func BenchmarkSendRecv(b *testing.B) {
+func BenchmarkSendRecvDERP(b *testing.B) {
+	benchmarkSendRecvSize := func(b *testing.B, packetSize int) {
+		serverPrivateKey := key.NewNode()
+		s := NewServer(serverPrivateKey, logger.Discard)
+		defer s.Close()
+
+		k := key.NewNode()
+		clientKey := k.Public()
+
+		ln, err := net.Listen("tcp", "127.0.0.1:0")
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer ln.Close()
+
+		connOut, err := net.Dial("tcp", ln.Addr().String())
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer connOut.Close()
+
+		connIn, err := ln.Accept()
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer connIn.Close()
+
+		brwServer := bufio.NewReadWriter(bufio.NewReader(connIn), bufio.NewWriter(connIn))
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		go s.Accept(ctx, connIn, brwServer, "test-client")
+
+		brw := bufio.NewReadWriter(bufio.NewReader(connOut), bufio.NewWriter(connOut))
+		client, err := NewClient(k, connOut, brw, logger.Discard)
+		if err != nil {
+			b.Fatalf("client: %v", err)
+		}
+
+		msg := make([]byte, packetSize)
+		rand.Read(msg)
+		b.SetBytes(int64(len(msg)))
+		b.ReportAllocs()
+
+		inFlight := syncs.NewSemaphore(28)
+
+		go func() {
+			for {
+				inFlight.Acquire()
+				if err := client.Send(clientKey, msg); err != nil {
+					connIn.Close()
+					connOut.Close()
+					return
+				}
+			}
+		}()
+
+		b.ResetTimer()
+		for range b.N {
+			if _, err := client.Recv(); err != nil {
+				b.Fatal(err)
+			}
+			inFlight.Release()
+		}
+	}
+
 	for _, size := range []int{10, 100, 1000, 10000} {
 		b.Run(fmt.Sprintf("msgsize=%d", size), func(b *testing.B) { benchmarkSendRecvSize(b, size) })
 	}
 }
 
-func benchmarkSendRecvSize(b *testing.B, packetSize int) {
-	serverPrivateKey := key.NewNode()
-	s := NewServer(serverPrivateKey, logger.Discard)
-	defer s.Close()
+func BenchmarkSendRecvQUIC(b *testing.B) {
+	benchmarkSendRecvSize := func(b *testing.B, packetSize int) {
+		serverPrivateKey := key.NewNode()
+		s := NewServer(serverPrivateKey, logger.Discard)
+		defer s.Close()
 
-	k := key.NewNode()
-	clientKey := k.Public()
+		k := key.NewNode()
+		clientKey := k.Public()
 
-	ln, err := net.Listen("tcp", "127.0.0.1:0")
-	if err != nil {
-		b.Fatal(err)
-	}
-	defer ln.Close()
+		qcfg := &quic.Config{}
 
-	connOut, err := net.Dial("tcp", ln.Addr().String())
-	if err != nil {
-		b.Fatal(err)
-	}
-	defer connOut.Close()
-
-	connIn, err := ln.Accept()
-	if err != nil {
-		b.Fatal(err)
-	}
-	defer connIn.Close()
-
-	brwServer := bufio.NewReadWriter(bufio.NewReader(connIn), bufio.NewWriter(connIn))
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go s.Accept(ctx, connIn, brwServer, "test-client")
-
-	brw := bufio.NewReadWriter(bufio.NewReader(connOut), bufio.NewWriter(connOut))
-	client, err := NewClient(k, connOut, brw, logger.Discard)
-	if err != nil {
-		b.Fatalf("client: %v", err)
-	}
-
-	go func() {
-		for {
-			_, err := client.Recv()
-			if err != nil {
-				return
-			}
-		}
-	}()
-
-	msg := make([]byte, packetSize)
-	b.SetBytes(int64(len(msg)))
-	b.ReportAllocs()
-	b.ResetTimer()
-	for range b.N {
-		if err := client.Send(clientKey, msg); err != nil {
+		ln, err := quic.ListenAddr("127.0.0.1:0", generateTLSConfig(), qcfg)
+		if err != nil {
 			b.Fatal(err)
 		}
+		defer ln.Close()
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		go func() {
+			qconnIn, err := ln.Accept(context.Background())
+			if err != nil {
+				b.Fatal(err)
+			}
+			defer qconnIn.CloseWithError(0, "")
+			_connIn, err := qconnIn.AcceptStream(context.Background())
+			if err != nil {
+				b.Fatal(err)
+			}
+			defer _connIn.Close()
+			connIn := &connWithAddr{_connIn, "server", qconnIn.LocalAddr()}
+
+			// read and discard initial byte
+			if _, err := connIn.Read(make([]byte, 1)); err != nil {
+				b.Fatal(err)
+			}
+
+			brwServer := bufio.NewReadWriter(bufio.NewReader(connIn), bufio.NewWriter(connIn))
+
+			s.Accept(ctx, connIn, brwServer, "test-client")
+		}()
+
+		tlsConf := &tls.Config{
+			InsecureSkipVerify: true,
+			// NextProtos:         []string{"quic-echo-example"},
+		}
+		qconnOut, err := quic.DialAddr(context.Background(), ln.Addr().String(), tlsConf, qcfg)
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer qconnOut.CloseWithError(0, "")
+
+		_connOut, err := qconnOut.OpenStream()
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer _connOut.Close()
+		connOut := &connWithAddr{_connOut, "client", qconnOut.LocalAddr()}
+
+		connOut.Write([]byte{0})
+		brw := bufio.NewReadWriter(bufio.NewReader(connOut), bufio.NewWriter(connOut))
+		client, err := NewClient(k, connOut, brw, logger.Discard)
+		if err != nil {
+			b.Fatalf("client: %v", err)
+		}
+
+		msg := make([]byte, packetSize)
+		rand.Read(msg)
+		b.SetBytes(int64(len(msg)))
+		b.ReportAllocs()
+
+		// inFlight := syncs.NewSemaphore(28)
+
+		go func() {
+			for {
+				// inFlight.Acquire()
+				if err := client.Send(clientKey, msg); err != nil {
+					fmt.Println(err)
+					connOut.Close()
+					return
+				}
+			}
+		}()
+
+		b.ResetTimer()
+		for range b.N {
+			if _, err := client.Recv(); err != nil {
+				b.Fatal(err)
+			}
+			// inFlight.Release()
+		}
+	}
+
+	for _, size := range []int{10, 100, 1000, 10000} {
+		// for _, size := range []int{10} {
+		b.Run(fmt.Sprintf("msgsize=%d", size), func(b *testing.B) { benchmarkSendRecvSize(b, size) })
 	}
 }
 
+type connWithAddr struct {
+	quic.Stream
+	label     string
+	localAddr net.Addr
+}
+
+func (c *connWithAddr) LocalAddr() net.Addr {
+	return c.localAddr
+}
+
+func (c *connWithAddr) Write(b []byte) (int, error) {
+	fmt.Printf("ZZZZ Writing length %d\n", len(b))
+	n, err := c.Stream.Write(b)
+	fmt.Printf("ZZZZ Wrote %d with error %v\n", n, err)
+	return n, err
+}
+
+// func BenchmarkSendRecvPlain(b *testing.B) {
+// 	benchmarkSendRecvSize := func(b *testing.B, packetSize int) {
+// 		ln, err := net.Listen("tcp", "127.0.0.1:0")
+// 		if err != nil {
+// 			b.Fatal(err)
+// 		}
+// 		defer ln.Close()
+
+// 		go func() {
+// 			for {
+// 				conn, err := ln.Accept()
+// 				if err != nil {
+// 					return
+// 				}
+// 				go io.Copy(conn, conn)
+// 			}
+// 		}()
+
+// 		conn, err := net.Dial("tcp", ln.Addr().String())
+// 		if err != nil {
+// 			b.Fatal(err)
+// 		}
+// 		defer conn.Close()
+
+// 		go io.Copy(io.Discard, conn)
+
+// 		msg := make([]byte, packetSize)
+// 		rand.Read(msg)
+// 		b.SetBytes(int64(len(msg)))
+// 		b.ReportAllocs()
+
+// 		type closeable interface {
+// 			CloseRead() error
+// 			CloseWrite() error
+// 		}
+
+// 		go func() {
+// 			defer conn.(closeable).CloseWrite()
+// 			for range b.N {
+// 				if _, err := conn.Write(msg); err != nil {
+// 					conn.Close()
+// 					return
+// 				}
+// 			}
+// 		}()
+// 		b.ResetTimer()
+
+// 		n, _ := io.CopyN(io.Discard, conn, int64(b.N)*int64(len(msg)))
+// 		log.Printf("copied %d\n", n)
+// 	}
+
+// 	for _, size := range []int{10, 100, 1000, 10000} {
+// 		b.Run(fmt.Sprintf("msgsize=%d", size), func(b *testing.B) { benchmarkSendRecvSize(b, size) })
+// 	}
+// }
+
 func BenchmarkWriteUint32(b *testing.B) {
 	w := bufio.NewWriter(io.Discard)
 	b.ReportAllocs()
@@ -1601,28 +1784,57 @@ func TestServerRepliesToPing(t *testing.T) {
 	}
 }
 
-func TestGetPerClientSendQueueDepth(t *testing.T) {
-	c := qt.New(t)
-	envKey := "TS_DEBUG_DERP_PER_CLIENT_SEND_QUEUE_DEPTH"
-
-	testCases := []struct {
-		envVal string
-		want   int
-	}{
-		// Empty case, envknob treats empty as missing also.
-		{
-			"", defaultPerClientSendQueueDepth,
+// Setup a bare-bones TLS config for the server
+func generateTLSConfig() *tls.Config {
+	return &tls.Config{
+		Certificates:       []tls.Certificate{testCert},
+		InsecureSkipVerify: true,
+		CipherSuites: []uint16{
+			tls.TLS_AES_128_GCM_SHA256,
+			tls.TLS_AES_256_GCM_SHA384,
+			tls.TLS_CHACHA20_POLY1305_SHA256,
 		},
-		{
-			"64", 64,
+		MinVersion: tls.VersionTLS13,
+		// Default key exchange mechanisms as of Go 1.23 minus X25519Kyber768Draft00,
+		// which bloats the client hello enough to spill into a second datagram.
+		// Tests were written with the assuption each flight in the handshake
+		// fits in one datagram, and it's simpler to keep that property.
+		CurvePreferences: []tls.CurveID{
+			tls.X25519, tls.CurveP256, tls.CurveP384, tls.CurveP521,
 		},
 	}
-
-	for _, tc := range testCases {
-		t.Run(cmp.Or(tc.envVal, "empty"), func(t *testing.T) {
-			t.Setenv(envKey, tc.envVal)
-			val := getPerClientSendQueueDepth()
-			c.Assert(val, qt.Equals, tc.want)
-		})
-	}
 }
+
+var testCert = func() tls.Certificate {
+	cert, err := tls.X509KeyPair(localhostCert, localhostKey)
+	if err != nil {
+		panic(err)
+	}
+	return cert
+}()
+
+// localhostCert is a PEM-encoded TLS cert with SAN IPs
+// "127.0.0.1" and "[::1]", expiring at Jan 29 16:00:00 2084 GMT.
+// generated from src/crypto/tls:
+// go run generate_cert.go  --ecdsa-curve P256 --host 127.0.0.1,::1,example.com --ca --start-date "Jan 1 00:00:00 1970" --duration=1000000h
+var localhostCert = []byte(`-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`)
+
+// localhostKey is the private key for localhostCert.
+var localhostKey = []byte(testingKey(`-----BEGIN TESTING KEY-----
+MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgY1B1eL/Bbwf/MDcs
+rnvvWhFNr1aGmJJR59PdCN9lVVqhRANCAARhWRF8p8X9scgW7JjqAwI9nYV8jtkd
+hqAXG9gyEgnaFNN5Ze9l3Tp1R9yCDBMNsGmsPyfMPe5Jrha/LmjgR1G9
+-----END TESTING KEY-----`))
+
+// testingKey helps keep security scanners from getting excited about a private key in this file.
+func testingKey(s string) string { return strings.ReplaceAll(s, "TESTING KEY", "PRIVATE KEY") }

derp/derphttp/derphttp_client.go

@@ -757,9 +757,6 @@ func (c *Client) dialNode(ctx context.Context, n *tailcfg.DERPNode) (net.Conn, e
 			}
 			dst := cmp.Or(dstPrimary, n.HostName)
 			port := "443"
-			if !c.useHTTPS() {
-				port = "3340"
-			}
 			if n.DERPPort != 0 {
 				port = fmt.Sprint(n.DERPPort)
 			}

derp/derphttp/derphttp_test.go

@@ -6,6 +6,7 @@ package derphttp
 import (
 	"bytes"
 	"context"
+	"crypto/rand"
 	"crypto/tls"
 	"fmt"
 	"net"
@@ -214,7 +215,12 @@ func TestPing(t *testing.T) {
 	}
 }
 
-func newTestServer(t *testing.T, k key.NodePrivate) (serverURL string, s *derp.Server) {
+type testingT interface {
+	Logf(format string, args ...any)
+	Fatal(args ...any)
+}
+
+func newTestServer(t testingT, k key.NodePrivate) (serverURL string, s *derp.Server) {
 	s = derp.NewServer(k, t.Logf)
 	httpsrv := &http.Server{
 		TLSNextProto: make(map[string]func(*http.Server, *tls.Conn, http.Handler)),
@@ -507,3 +513,51 @@ func TestDeps(t *testing.T) {
 	}.Check(t)
 
 }
+
+func BenchmarkSendRecvDERP(b *testing.B) {
+	benchmarkSendRecvSize := func(b *testing.B, packetSize int) {
+		serverPrivateKey := key.NewNode()
+		serverURL, s := newTestServer(b, serverPrivateKey)
+		defer s.Close()
+
+		k := key.NewNode()
+		clientKey := k.Public()
+
+		ln, err := net.Listen("tcp", "127.0.0.1:0")
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer ln.Close()
+
+		client, err := NewClient(k, serverURL, b.Logf, netmon.NewStatic())
+		if err != nil {
+			b.Fatal(err)
+		}
+		defer client.Close()
+
+		msg := make([]byte, packetSize)
+		rand.Read(msg)
+		b.SetBytes(int64(len(msg)))
+		b.ReportAllocs()
+
+		go func() {
+			for {
+				if err := client.Send(clientKey, msg); err != nil {
+					client.Close()
+					return
+				}
+			}
+		}()
+
+		b.ResetTimer()
+		for range b.N {
+			if _, err := client.Recv(); err != nil {
+				b.Fatal(err)
+			}
+		}
+	}
+
+	for _, size := range []int{10, 100, 1000, 10000} {
+		b.Run(fmt.Sprintf("msgsize=%d", size), func(b *testing.B) { benchmarkSendRecvSize(b, size) })
+	}
+}

go.mod

@@ -96,7 +96,7 @@ require (
 	go4.org/mem v0.0.0-20220726221520-4f986261bf13
 	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba
 	golang.org/x/crypto v0.30.0
-	golang.org/x/exp v0.0.0-20240119083558-1b970713d09a
+	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842
 	golang.org/x/mod v0.19.0
 	golang.org/x/net v0.32.0
 	golang.org/x/oauth2 v0.16.0
@@ -143,6 +143,7 @@ require (
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/ghostiam/protogetter v0.3.5 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572 // indirect
 	github.com/go-viper/mapstructure/v2 v2.0.0-alpha.1 // indirect
 	github.com/gobuffalo/flect v1.0.2 // indirect
 	github.com/goccy/go-yaml v1.12.0 // indirect
@@ -155,6 +156,8 @@ require (
 	github.com/karamaru-alpha/copyloopvar v1.0.8 // indirect
 	github.com/macabu/inamedparam v0.1.3 // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
+	github.com/onsi/ginkgo/v2 v2.17.1 // indirect
+	github.com/quic-go/quic-go v0.48.2-0.20241205065829-2dca400b5c16 // indirect
 	github.com/santhosh-tekuri/jsonschema/v5 v5.3.1 // indirect
 	github.com/xen0n/gosmopolitan v1.2.2 // indirect
 	github.com/ykadowak/zerologlint v0.1.5 // indirect
@@ -165,6 +168,7 @@ require (
 	go.opentelemetry.io/otel/metric v1.32.0 // indirect
 	go.opentelemetry.io/otel/trace v1.32.0 // indirect
 	go.uber.org/automaxprocs v1.5.3 // indirect
+	go.uber.org/mock v0.4.0 // indirect
 	golang.org/x/xerrors v0.0.0-20240716161551-93cc26a95ae9 // indirect
 )
 

go.sum

@@ -821,6 +821,10 @@ github.com/quasilyte/regex/syntax v0.0.0-20210819130434-b3f0c404a727 h1:TCg2WBOl
 github.com/quasilyte/regex/syntax v0.0.0-20210819130434-b3f0c404a727/go.mod h1:rlzQ04UMyJXu/aOvhd8qT+hvDrFpiwqp8MRXDY9szc0=
 github.com/quasilyte/stdinfo v0.0.0-20220114132959-f7386bf02567 h1:M8mH9eK4OUR4lu7Gd+PU1fV2/qnDNfzT635KRSObncs=
 github.com/quasilyte/stdinfo v0.0.0-20220114132959-f7386bf02567/go.mod h1:DWNGW8A4Y+GyBgPuaQJuWiy0XYftx4Xm/y5Jqk9I6VQ=
+github.com/quic-go/quic-go v0.48.2-0.20241205065829-2dca400b5c16 h1:qKr8kL9UtS7OMpCRvR+o/ixevCsHq7GYBsvhU1d78eU=
+github.com/quic-go/quic-go v0.48.2-0.20241205065829-2dca400b5c16/go.mod h1:9RyLbf3jjSZB+/l5DgQ4KFq/fguTLs6WAJaK4mfDJw8=
+github.com/quic-go/quic-go v0.48.2 h1:wsKXZPeGWpMpCGSWqOcqpW2wZYic/8T3aqiOID0/KWE=
+github.com/quic-go/quic-go v0.48.2/go.mod h1:yBgs3rWBOADpga7F+jJsb6Ybg1LSYiQvwWlLX+/6HMs=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.4.4 h1:8TfxU8dW6PdqD27gjM8MVNuicgxIjxpm4K7x4jp8sis=
 github.com/rivo/uniseg v0.4.4/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
@@ -904,6 +908,7 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
@@ -1042,6 +1047,8 @@ go.uber.org/automaxprocs v1.5.3 h1:kWazyxZUrS3Gs4qUpbwo5kEIMGe/DAvi5Z4tl2NW4j8=
 go.uber.org/automaxprocs v1.5.3/go.mod h1:eRbA25aqJrxAbsLO0xy5jVwPt7FQnRgjW+efnwa1WM0=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
+go.uber.org/mock v0.4.0 h1:VcM4ZOtdbR4f6VXfiOpwpVJDL6lCReaZ6mw31wqh7KU=
+go.uber.org/mock v0.4.0/go.mod h1:a6FSlNadKUHUa9IP5Vyt1zh4fC7uAwxMutEAscFbkZc=
 go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
 go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
 go.uber.org/zap v1.27.0 h1:aJMhYGrd5QSmlpLMr2MftRKl7t8J8PTZPA732ud/XR8=
@@ -1076,6 +1083,8 @@ golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EH
 golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6/go.mod h1:3jZMyOhIsHpP37uCMkUooju7aAi5cS1Q23tOzKc+0MU=
 golang.org/x/exp v0.0.0-20240119083558-1b970713d09a h1:Q8/wZp0KX97QFTc2ywcOE0YRjZPVIx+MXInMzdvQqcA=
 golang.org/x/exp v0.0.0-20240119083558-1b970713d09a/go.mod h1:idGWGoKP1toJGkd5/ig9ZLuPcZBC3ewk7SzmH0uou08=
+golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842 h1:vr/HnozRka3pE4EsMEg1lgkXJkTFJCVUX+S/ZT6wYzM=
+golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842/go.mod h1:XtvwrStGgqGPLc4cjQfWqZHG1YFdYs6swckp8vpsjnc=
 golang.org/x/exp/typeparams v0.0.0-20220428152302-39d4317da171/go.mod h1:AbB0pIl9nAr9wVwH+Z2ZpaocVmF5I4GyWCDIsVjR0bk=
 golang.org/x/exp/typeparams v0.0.0-20230203172020-98cc5a0785f9/go.mod h1:AbB0pIl9nAr9wVwH+Z2ZpaocVmF5I4GyWCDIsVjR0bk=
 golang.org/x/exp/typeparams v0.0.0-20240314144324-c7f7c6466f7f h1:phY1HzDcf18Aq9A8KkmRtY9WvOFIxN8wgfvy6Zm1DV8=

hostinfo/hostinfo_linux_test.go

@@ -35,12 +35,8 @@ remotes/origin/QTSFW_5.0.0`
 	}
 }
 
-func TestPackageTypeNotContainer(t *testing.T) {
-	var got string
-	if packageType != nil {
-		got = packageType()
-	}
-	if got == "container" {
-		t.Fatal("packageType = container; should only happen if build tag ts_package_container is set")
+func TestInContainer(t *testing.T) {
+	if got := inContainer(); !got.EqualBool(false) {
+		t.Errorf("inContainer = %v; want false due to absence of ts_package_container build tag", got)
 	}
 }

k8s-operator/conditions.go

@@ -167,14 +167,3 @@ func DNSCfgIsReady(cfg *tsapi.DNSConfig) bool {
 	cond := cfg.Status.Conditions[idx]
 	return cond.Status == metav1.ConditionTrue && cond.ObservedGeneration == cfg.Generation
 }
-
-func SvcIsReady(svc *corev1.Service) bool {
-	idx := xslices.IndexFunc(svc.Status.Conditions, func(cond metav1.Condition) bool {
-		return cond.Type == string(tsapi.ProxyReady)
-	})
-	if idx == -1 {
-		return false
-	}
-	cond := svc.Status.Conditions[idx]
-	return cond.Status == metav1.ConditionTrue
-}

prober/derp.go

@@ -597,22 +597,18 @@ func newConn(ctx context.Context, dm *tailcfg.DERPMap, n *tailcfg.DERPNode, isPr
 	if err != nil {
 		return nil, err
 	}
-
-	// Only verify TLS state if this is a prober.
-	if isProber {
-		cs, ok := dc.TLSConnectionState()
-		if !ok {
-			dc.Close()
-			return nil, errors.New("no TLS state")
-		}
-		if len(cs.PeerCertificates) == 0 {
-			dc.Close()
-			return nil, errors.New("no peer certificates")
-		}
-		if cs.ServerName != n.HostName {
-			dc.Close()
-			return nil, fmt.Errorf("TLS server name %q != derp hostname %q", cs.ServerName, n.HostName)
-		}
+	cs, ok := dc.TLSConnectionState()
+	if !ok {
+		dc.Close()
+		return nil, errors.New("no TLS state")
+	}
+	if len(cs.PeerCertificates) == 0 {
+		dc.Close()
+		return nil, errors.New("no peer certificates")
+	}
+	if cs.ServerName != n.HostName {
+		dc.Close()
+		return nil, fmt.Errorf("TLS server name %q != derp hostname %q", cs.ServerName, n.HostName)
 	}
 
 	errc := make(chan error, 1)

ssh/tailssh/tailssh.go

@@ -10,6 +10,7 @@ import (
 	"bytes"
 	"context"
 	"crypto/rand"
+	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -44,6 +45,7 @@ import (
 	"tailscale.com/util/clientmetric"
 	"tailscale.com/util/httpm"
 	"tailscale.com/util/mak"
+	"tailscale.com/util/slicesx"
 )
 
 var (
@@ -78,14 +80,16 @@ type server struct {
 	logf           logger.Logf
 	tailscaledPath string
 
-	timeNow func() time.Time // or nil for time.Now
+	pubKeyHTTPClient *http.Client     // or nil for http.DefaultClient
+	timeNow          func() time.Time // or nil for time.Now
 
 	sessionWaitGroup sync.WaitGroup
 
 	// mu protects the following
-	mu             sync.Mutex
-	activeConns    map[*conn]bool // set; value is always true
-	shutdownCalled bool
+	mu                   sync.Mutex
+	activeConns          map[*conn]bool              // set; value is always true
+	fetchPublicKeysCache map[string]pubKeyCacheEntry // by https URL
+	shutdownCalled       bool
 }
 
 func (srv *server) now() time.Time {
@@ -200,6 +204,7 @@ func (srv *server) OnPolicyChange() {
 //
 // Do the user auth
 //   - NoClientAuthHandler
+//   - PublicKeyHandler (only if NoClientAuthHandler returns errPubKeyRequired)
 //
 // Once auth is done, the conn can be multiplexed with multiple sessions and
 // channels concurrently. At which point any of the following can be called
@@ -229,9 +234,10 @@ type conn struct {
 	finalAction    *tailcfg.SSHAction // set by doPolicyAuth or resolveNextAction
 	finalActionErr error              // set by doPolicyAuth or resolveNextAction
 
-	info         *sshConnInfo // set by setInfo
-	localUser    *userMeta    // set by doPolicyAuth
-	userGroupIDs []string     // set by doPolicyAuth
+	info         *sshConnInfo    // set by setInfo
+	localUser    *userMeta       // set by doPolicyAuth
+	userGroupIDs []string        // set by doPolicyAuth
+	pubKey       gossh.PublicKey // set by doPolicyAuth
 	acceptEnv    []string
 
 	// mu protects the following fields.
@@ -262,6 +268,9 @@ func (c *conn) isAuthorized(ctx ssh.Context) error {
 	action := c.currentAction
 	for {
 		if action.Accept {
+			if c.pubKey != nil {
+				metricPublicKeyAccepts.Add(1)
+			}
 			return nil
 		}
 		if action.Reject || action.HoldAndDelegate == "" {
@@ -284,6 +293,10 @@ func (c *conn) isAuthorized(ctx ssh.Context) error {
 // policy.
 var errDenied = errors.New("ssh: access denied")
 
+// errPubKeyRequired is returned by NoClientAuthCallback to make the client
+// resort to public-key auth; not user visible.
+var errPubKeyRequired = errors.New("ssh publickey required")
+
 // NoClientAuthCallback implements gossh.NoClientAuthCallback and is called by
 // the ssh.Server when the client first connects with the "none"
 // authentication method.
@@ -292,12 +305,13 @@ var errDenied = errors.New("ssh: access denied")
 // starting it afresh). It returns an error if the policy evaluation fails, or
 // if the decision is "reject"
 //
-// It either returns nil (accept) or errDenied (reject). The errors may be wrapped.
+// It either returns nil (accept) or errPubKeyRequired or errDenied
+// (reject). The errors may be wrapped.
 func (c *conn) NoClientAuthCallback(ctx ssh.Context) error {
 	if c.insecureSkipTailscaleAuth {
 		return nil
 	}
-	if err := c.doPolicyAuth(ctx); err != nil {
+	if err := c.doPolicyAuth(ctx, nil /* no pub key */); err != nil {
 		return err
 	}
 	if err := c.isAuthorized(ctx); err != nil {
@@ -318,6 +332,8 @@ func (c *conn) nextAuthMethodCallback(cm gossh.ConnMetadata, prevErrors []error)
 	switch {
 	case c.anyPasswordIsOkay:
 		nextMethod = append(nextMethod, "password")
+	case slicesx.LastEqual(prevErrors, errPubKeyRequired):
+		nextMethod = append(nextMethod, "publickey")
 	}
 
 	// The fake "tailscale" method is always appended to next so OpenSSH renders
@@ -337,20 +353,41 @@ func (c *conn) fakePasswordHandler(ctx ssh.Context, password string) bool {
 	return c.anyPasswordIsOkay
 }
 
-// doPolicyAuth verifies that conn can proceed.
-// It returns nil if the matching policy action is Accept or
-// HoldAndDelegate. Otherwise, it returns errDenied.
-func (c *conn) doPolicyAuth(ctx ssh.Context) error {
+// PublicKeyHandler implements ssh.PublicKeyHandler is called by the
+// ssh.Server when the client presents a public key.
+func (c *conn) PublicKeyHandler(ctx ssh.Context, pubKey ssh.PublicKey) error {
+	if err := c.doPolicyAuth(ctx, pubKey); err != nil {
+		// TODO(maisem/bradfitz): surface the error here.
+		c.logf("rejecting SSH public key %s: %v", bytes.TrimSpace(gossh.MarshalAuthorizedKey(pubKey)), err)
+		return err
+	}
+	if err := c.isAuthorized(ctx); err != nil {
+		return err
+	}
+	c.logf("accepting SSH public key %s", bytes.TrimSpace(gossh.MarshalAuthorizedKey(pubKey)))
+	return nil
+}
+
+// doPolicyAuth verifies that conn can proceed with the specified (optional)
+// pubKey. It returns nil if the matching policy action is Accept or
+// HoldAndDelegate. If pubKey is nil, there was no policy match but there is a
+// policy that might match a public key it returns errPubKeyRequired. Otherwise,
+// it returns errDenied.
+func (c *conn) doPolicyAuth(ctx ssh.Context, pubKey ssh.PublicKey) error {
 	if err := c.setInfo(ctx); err != nil {
 		c.logf("failed to get conninfo: %v", err)
 		return errDenied
 	}
-	a, localUser, acceptEnv, err := c.evaluatePolicy()
+	a, localUser, acceptEnv, err := c.evaluatePolicy(pubKey)
 	if err != nil {
+		if pubKey == nil && c.havePubKeyPolicy() {
+			return errPubKeyRequired
+		}
 		return fmt.Errorf("%w: %v", errDenied, err)
 	}
 	c.action0 = a
 	c.currentAction = a
+	c.pubKey = pubKey
 	c.acceptEnv = acceptEnv
 	if a.Message != "" {
 		if err := ctx.SendAuthBanner(a.Message); err != nil {
@@ -411,6 +448,7 @@ func (srv *server) newConn() (*conn, error) {
 		ServerConfigCallback: c.ServerConfig,
 
 		NoClientAuthHandler: c.NoClientAuthCallback,
+		PublicKeyHandler:    c.PublicKeyHandler,
 		PasswordHandler:     c.fakePasswordHandler,
 
 		Handler:                       c.handleSessionPostSSHAuth,
@@ -478,6 +516,34 @@ func (c *conn) mayForwardLocalPortTo(ctx ssh.Context, destinationHost string, de
 	return false
 }
 
+// havePubKeyPolicy reports whether any policy rule may provide access by means
+// of a ssh.PublicKey.
+func (c *conn) havePubKeyPolicy() bool {
+	if c.info == nil {
+		panic("havePubKeyPolicy called before setInfo")
+	}
+	// Is there any rule that looks like it'd require a public key for this
+	// sshUser?
+	pol, ok := c.sshPolicy()
+	if !ok {
+		return false
+	}
+	for _, r := range pol.Rules {
+		if c.ruleExpired(r) {
+			continue
+		}
+		if mapLocalUser(r.SSHUsers, c.info.sshUser) == "" {
+			continue
+		}
+		for _, p := range r.Principals {
+			if len(p.PubKeys) > 0 && c.principalMatchesTailscaleIdentity(p) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // sshPolicy returns the SSHPolicy for current node.
 // If there is no SSHPolicy in the netmap, it returns a debugPolicy
 // if one is defined.
@@ -554,19 +620,117 @@ func (c *conn) setInfo(ctx ssh.Context) error {
 }
 
 // evaluatePolicy returns the SSHAction and localUser after evaluating
-// the SSHPolicy for this conn.
-func (c *conn) evaluatePolicy() (_ *tailcfg.SSHAction, localUser string, acceptEnv []string, _ error) {
+// the SSHPolicy for this conn. The pubKey may be nil for "none" auth.
+func (c *conn) evaluatePolicy(pubKey gossh.PublicKey) (_ *tailcfg.SSHAction, localUser string, acceptEnv []string, _ error) {
 	pol, ok := c.sshPolicy()
 	if !ok {
 		return nil, "", nil, fmt.Errorf("tailssh: rejecting connection; no SSH policy")
 	}
-	a, localUser, acceptEnv, ok := c.evalSSHPolicy(pol)
+	a, localUser, acceptEnv, ok := c.evalSSHPolicy(pol, pubKey)
 	if !ok {
 		return nil, "", nil, fmt.Errorf("tailssh: rejecting connection; no matching policy")
 	}
 	return a, localUser, acceptEnv, nil
 }
 
+// pubKeyCacheEntry is the cache value for an HTTPS URL of public keys (like
+// "https://github.com/foo.keys")
+type pubKeyCacheEntry struct {
+	lines []string
+	etag  string // if sent by server
+	at    time.Time
+}
+
+const (
+	pubKeyCacheDuration      = time.Minute      // how long to cache non-empty public keys
+	pubKeyCacheEmptyDuration = 15 * time.Second // how long to cache empty responses
+)
+
+func (srv *server) fetchPublicKeysURLCached(url string) (ce pubKeyCacheEntry, ok bool) {
+	srv.mu.Lock()
+	defer srv.mu.Unlock()
+	// Mostly don't care about the size of this cache. Clean rarely.
+	if m := srv.fetchPublicKeysCache; len(m) > 50 {
+		tooOld := srv.now().Add(pubKeyCacheDuration * 10)
+		for k, ce := range m {
+			if ce.at.Before(tooOld) {
+				delete(m, k)
+			}
+		}
+	}
+	ce, ok = srv.fetchPublicKeysCache[url]
+	if !ok {
+		return ce, false
+	}
+	maxAge := pubKeyCacheDuration
+	if len(ce.lines) == 0 {
+		maxAge = pubKeyCacheEmptyDuration
+	}
+	return ce, srv.now().Sub(ce.at) < maxAge
+}
+
+func (srv *server) pubKeyClient() *http.Client {
+	if srv.pubKeyHTTPClient != nil {
+		return srv.pubKeyHTTPClient
+	}
+	return http.DefaultClient
+}
+
+// fetchPublicKeysURL fetches the public keys from a URL. The strings are in the
+// the typical public key "type base64-string [comment]" format seen at e.g.
+// https://github.com/USER.keys
+func (srv *server) fetchPublicKeysURL(url string) ([]string, error) {
+	if !strings.HasPrefix(url, "https://") {
+		return nil, errors.New("invalid URL scheme")
+	}
+
+	ce, ok := srv.fetchPublicKeysURLCached(url)
+	if ok {
+		return ce.lines, nil
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	if ce.etag != "" {
+		req.Header.Add("If-None-Match", ce.etag)
+	}
+	res, err := srv.pubKeyClient().Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	var lines []string
+	var etag string
+	switch res.StatusCode {
+	default:
+		err = fmt.Errorf("unexpected status %v", res.Status)
+		srv.logf("fetching public keys from %s: %v", url, err)
+	case http.StatusNotModified:
+		lines = ce.lines
+		etag = ce.etag
+	case http.StatusOK:
+		var all []byte
+		all, err = io.ReadAll(io.LimitReader(res.Body, 4<<10))
+		if s := strings.TrimSpace(string(all)); s != "" {
+			lines = strings.Split(s, "\n")
+		}
+		etag = res.Header.Get("Etag")
+	}
+
+	srv.mu.Lock()
+	defer srv.mu.Unlock()
+	mak.Set(&srv.fetchPublicKeysCache, url, pubKeyCacheEntry{
+		at:    srv.now(),
+		lines: lines,
+		etag:  etag,
+	})
+	return lines, err
+}
+
 // handleSessionPostSSHAuth runs an SSH session after the SSH-level authentication,
 // but not necessarily before all the Tailscale-level extra verification has
 // completed. It also handles SFTP requests.
@@ -668,6 +832,18 @@ func (c *conn) expandDelegateURLLocked(actionURL string) string {
 	).Replace(actionURL)
 }
 
+func (c *conn) expandPublicKeyURL(pubKeyURL string) string {
+	if !strings.Contains(pubKeyURL, "$") {
+		return pubKeyURL
+	}
+	loginName := c.info.uprof.LoginName
+	localPart, _, _ := strings.Cut(loginName, "@")
+	return strings.NewReplacer(
+		"$LOGINNAME_EMAIL", loginName,
+		"$LOGINNAME_LOCALPART", localPart,
+	).Replace(pubKeyURL)
+}
+
 // sshSession is an accepted Tailscale SSH session.
 type sshSession struct {
 	ssh.Session
@@ -718,7 +894,7 @@ func (c *conn) newSSHSession(s ssh.Session) *sshSession {
 
 // isStillValid reports whether the conn is still valid.
 func (c *conn) isStillValid() bool {
-	a, localUser, _, err := c.evaluatePolicy()
+	a, localUser, _, err := c.evaluatePolicy(c.pubKey)
 	c.vlogf("stillValid: %+v %v %v", a, localUser, err)
 	if err != nil {
 		return false
@@ -1101,9 +1277,9 @@ func (c *conn) ruleExpired(r *tailcfg.SSHRule) bool {
 	return r.RuleExpires.Before(c.srv.now())
 }
 
-func (c *conn) evalSSHPolicy(pol *tailcfg.SSHPolicy) (a *tailcfg.SSHAction, localUser string, acceptEnv []string, ok bool) {
+func (c *conn) evalSSHPolicy(pol *tailcfg.SSHPolicy, pubKey gossh.PublicKey) (a *tailcfg.SSHAction, localUser string, acceptEnv []string, ok bool) {
 	for _, r := range pol.Rules {
-		if a, localUser, acceptEnv, err := c.matchRule(r); err == nil {
+		if a, localUser, acceptEnv, err := c.matchRule(r, pubKey); err == nil {
 			return a, localUser, acceptEnv, true
 		}
 	}
@@ -1120,7 +1296,7 @@ var (
 	errInvalidConn    = errors.New("invalid connection state")
 )
 
-func (c *conn) matchRule(r *tailcfg.SSHRule) (a *tailcfg.SSHAction, localUser string, acceptEnv []string, err error) {
+func (c *conn) matchRule(r *tailcfg.SSHRule, pubKey gossh.PublicKey) (a *tailcfg.SSHAction, localUser string, acceptEnv []string, err error) {
 	defer func() {
 		c.vlogf("matchRule(%+v): %v", r, err)
 	}()
@@ -1150,7 +1326,9 @@ func (c *conn) matchRule(r *tailcfg.SSHRule) (a *tailcfg.SSHAction, localUser st
 			return nil, "", nil, errUserMatch
 		}
 	}
-	if !c.anyPrincipalMatches(r.Principals) {
+	if ok, err := c.anyPrincipalMatches(r.Principals, pubKey); err != nil {
+		return nil, "", nil, err
+	} else if !ok {
 		return nil, "", nil, errPrincipalMatch
 	}
 	return r.Action, localUser, r.AcceptEnv, nil
@@ -1167,20 +1345,30 @@ func mapLocalUser(ruleSSHUsers map[string]string, reqSSHUser string) (localUser
 	return v
 }
 
-func (c *conn) anyPrincipalMatches(ps []*tailcfg.SSHPrincipal) bool {
+func (c *conn) anyPrincipalMatches(ps []*tailcfg.SSHPrincipal, pubKey gossh.PublicKey) (bool, error) {
 	for _, p := range ps {
 		if p == nil {
 			continue
 		}
-		if c.principalMatchesTailscaleIdentity(p) {
-			return true
+		if ok, err := c.principalMatches(p, pubKey); err != nil {
+			return false, err
+		} else if ok {
+			return true, nil
 		}
 	}
-	return false
+	return false, nil
+}
+
+func (c *conn) principalMatches(p *tailcfg.SSHPrincipal, pubKey gossh.PublicKey) (bool, error) {
+	if !c.principalMatchesTailscaleIdentity(p) {
+		return false, nil
+	}
+	return c.principalMatchesPubKey(p, pubKey)
 }
 
 // principalMatchesTailscaleIdentity reports whether one of p's four fields
 // that match the Tailscale identity match (Node, NodeIP, UserLogin, Any).
+// This function does not consider PubKeys.
 func (c *conn) principalMatchesTailscaleIdentity(p *tailcfg.SSHPrincipal) bool {
 	ci := c.info
 	if p.Any {
@@ -1200,6 +1388,42 @@ func (c *conn) principalMatchesTailscaleIdentity(p *tailcfg.SSHPrincipal) bool {
 	return false
 }
 
+func (c *conn) principalMatchesPubKey(p *tailcfg.SSHPrincipal, clientPubKey gossh.PublicKey) (bool, error) {
+	if len(p.PubKeys) == 0 {
+		return true, nil
+	}
+	if clientPubKey == nil {
+		return false, nil
+	}
+	knownKeys := p.PubKeys
+	if len(knownKeys) == 1 && strings.HasPrefix(knownKeys[0], "https://") {
+		var err error
+		knownKeys, err = c.srv.fetchPublicKeysURL(c.expandPublicKeyURL(knownKeys[0]))
+		if err != nil {
+			return false, err
+		}
+	}
+	for _, knownKey := range knownKeys {
+		if pubKeyMatchesAuthorizedKey(clientPubKey, knownKey) {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func pubKeyMatchesAuthorizedKey(pubKey ssh.PublicKey, wantKey string) bool {
+	wantKeyType, rest, ok := strings.Cut(wantKey, " ")
+	if !ok {
+		return false
+	}
+	if pubKey.Type() != wantKeyType {
+		return false
+	}
+	wantKeyB64, _, _ := strings.Cut(rest, " ")
+	wantKeyData, _ := base64.StdEncoding.DecodeString(wantKeyB64)
+	return len(wantKeyData) > 0 && bytes.Equal(pubKey.Marshal(), wantKeyData)
+}
+
 func randBytes(n int) []byte {
 	b := make([]byte, n)
 	if _, err := rand.Read(b); err != nil {
@@ -1525,6 +1749,7 @@ func envEq(a, b string) bool {
 var (
 	metricActiveSessions      = clientmetric.NewGauge("ssh_active_sessions")
 	metricIncomingConnections = clientmetric.NewCounter("ssh_incoming_connections")
+	metricPublicKeyAccepts    = clientmetric.NewCounter("ssh_publickey_accepts") // accepted subset of ssh_publickey_connections
 	metricTerminalAccept      = clientmetric.NewCounter("ssh_terminalaction_accept")
 	metricTerminalReject      = clientmetric.NewCounter("ssh_terminalaction_reject")
 	metricTerminalMalformed   = clientmetric.NewCounter("ssh_terminalaction_malformed")

ssh/tailssh/tailssh_test.go

@@ -10,6 +10,7 @@ import (
 	"context"
 	"crypto/ed25519"
 	"crypto/rand"
+	"crypto/sha256"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -228,7 +229,7 @@ func TestMatchRule(t *testing.T) {
 				info: tt.ci,
 				srv:  &server{logf: t.Logf},
 			}
-			got, gotUser, gotAcceptEnv, err := c.matchRule(tt.rule)
+			got, gotUser, gotAcceptEnv, err := c.matchRule(tt.rule, nil)
 			if err != tt.wantErr {
 				t.Errorf("err = %v; want %v", err, tt.wantErr)
 			}
@@ -347,7 +348,7 @@ func TestEvalSSHPolicy(t *testing.T) {
 				info: tt.ci,
 				srv:  &server{logf: t.Logf},
 			}
-			got, gotUser, gotAcceptEnv, match := c.evalSSHPolicy(tt.policy)
+			got, gotUser, gotAcceptEnv, match := c.evalSSHPolicy(tt.policy, nil)
 			if match != tt.wantMatch {
 				t.Errorf("match = %v; want %v", match, tt.wantMatch)
 			}
@@ -1128,6 +1129,89 @@ func parseEnv(out []byte) map[string]string {
 	return e
 }
 
+func TestPublicKeyFetching(t *testing.T) {
+	var reqsTotal, reqsIfNoneMatchHit, reqsIfNoneMatchMiss int32
+	ts := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		atomic.AddInt32((&reqsTotal), 1)
+		etag := fmt.Sprintf("W/%q", sha256.Sum256([]byte(r.URL.Path)))
+		w.Header().Set("Etag", etag)
+		if v := r.Header.Get("If-None-Match"); v != "" {
+			if v == etag {
+				atomic.AddInt32(&reqsIfNoneMatchHit, 1)
+				w.WriteHeader(304)
+				return
+			}
+			atomic.AddInt32(&reqsIfNoneMatchMiss, 1)
+		}
+		io.WriteString(w, "foo\nbar\n"+string(r.URL.Path)+"\n")
+	}))
+	ts.StartTLS()
+	defer ts.Close()
+	keys := ts.URL
+
+	clock := &tstest.Clock{}
+	srv := &server{
+		pubKeyHTTPClient: ts.Client(),
+		timeNow:          clock.Now,
+	}
+	for range 2 {
+		got, err := srv.fetchPublicKeysURL(keys + "/alice.keys")
+		if err != nil {
+			t.Fatal(err)
+		}
+		if want := []string{"foo", "bar", "/alice.keys"}; !reflect.DeepEqual(got, want) {
+			t.Errorf("got %q; want %q", got, want)
+		}
+	}
+	if got, want := atomic.LoadInt32(&reqsTotal), int32(1); got != want {
+		t.Errorf("got %d requests; want %d", got, want)
+	}
+	if got, want := atomic.LoadInt32(&reqsIfNoneMatchHit), int32(0); got != want {
+		t.Errorf("got %d etag hits; want %d", got, want)
+	}
+	clock.Advance(5 * time.Minute)
+	got, err := srv.fetchPublicKeysURL(keys + "/alice.keys")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want := []string{"foo", "bar", "/alice.keys"}; !reflect.DeepEqual(got, want) {
+		t.Errorf("got %q; want %q", got, want)
+	}
+	if got, want := atomic.LoadInt32(&reqsTotal), int32(2); got != want {
+		t.Errorf("got %d requests; want %d", got, want)
+	}
+	if got, want := atomic.LoadInt32(&reqsIfNoneMatchHit), int32(1); got != want {
+		t.Errorf("got %d etag hits; want %d", got, want)
+	}
+	if got, want := atomic.LoadInt32(&reqsIfNoneMatchMiss), int32(0); got != want {
+		t.Errorf("got %d etag misses; want %d", got, want)
+	}
+
+}
+
+func TestExpandPublicKeyURL(t *testing.T) {
+	c := &conn{
+		info: &sshConnInfo{
+			uprof: tailcfg.UserProfile{
+				LoginName: "bar@baz.tld",
+			},
+		},
+	}
+	if got, want := c.expandPublicKeyURL("foo"), "foo"; got != want {
+		t.Errorf("basic: got %q; want %q", got, want)
+	}
+	if got, want := c.expandPublicKeyURL("https://example.com/$LOGINNAME_LOCALPART.keys"), "https://example.com/bar.keys"; got != want {
+		t.Errorf("localpart: got %q; want %q", got, want)
+	}
+	if got, want := c.expandPublicKeyURL("https://example.com/keys?email=$LOGINNAME_EMAIL"), "https://example.com/keys?email=bar@baz.tld"; got != want {
+		t.Errorf("email: got %q; want %q", got, want)
+	}
+	c.info = new(sshConnInfo)
+	if got, want := c.expandPublicKeyURL("https://example.com/keys?email=$LOGINNAME_EMAIL"), "https://example.com/keys?email="; got != want {
+		t.Errorf("on empty: got %q; want %q", got, want)
+	}
+}
+
 func TestAcceptEnvPair(t *testing.T) {
 	tests := []struct {
 		in   string

tailcfg/tailcfg.go

@@ -152,8 +152,7 @@ type CapabilityVersion int
 //   - 107: 2024-10-30: add App Connector to conffile (PR #13942)
 //   - 108: 2024-11-08: Client sends ServicesHash in Hostinfo, understands c2n GET /vip-services.
 //   - 109: 2024-11-18: Client supports filtertype.Match.SrcCaps (issue #12542)
-//   - 110: 2024-12-12: removed never-before-used Tailscale SSH public key support (#14373)
-const CurrentCapabilityVersion CapabilityVersion = 110
+const CurrentCapabilityVersion CapabilityVersion = 109
 
 type StableID string
 
@@ -2526,13 +2525,16 @@ type SSHPrincipal struct {
 	Any       bool         `json:"any,omitempty"`       // if true, match any connection
 	// TODO(bradfitz): add StableUserID, once that exists
 
-	// UnusedPubKeys was public key support. It never became an official product
-	// feature and so as of 2024-12-12 is being removed.
-	// This stub exists to remind us not to re-use the JSON field name "pubKeys"
-	// in the future if we bring it back with different semantics.
+	// PubKeys, if non-empty, means that this SSHPrincipal only
+	// matches if one of these public keys is presented by the user.
 	//
-	// Deprecated: do not use. It does nothing.
-	UnusedPubKeys []string `json:"pubKeys,omitempty"`
+	// As a special case, if len(PubKeys) == 1 and PubKeys[0] starts
+	// with "https://", then it's fetched (like https://github.com/username.keys).
+	// In that case, the following variable expansions are also supported
+	// in the URL:
+	//   * $LOGINNAME_EMAIL ("foo@bar.com" or "foo@github")
+	//   * $LOGINNAME_LOCALPART (the "foo" from either of the above)
+	PubKeys []string `json:"pubKeys,omitempty"`
 }
 
 // SSHAction is how to handle an incoming connection.

tailcfg/tailcfg_clone.go

@@ -556,17 +556,17 @@ func (src *SSHPrincipal) Clone() *SSHPrincipal {
 	}
 	dst := new(SSHPrincipal)
 	*dst = *src
-	dst.UnusedPubKeys = append(src.UnusedPubKeys[:0:0], src.UnusedPubKeys...)
+	dst.PubKeys = append(src.PubKeys[:0:0], src.PubKeys...)
 	return dst
 }
 
 // A compilation failure here means this code must be regenerated, with the command at the top of this file.
 var _SSHPrincipalCloneNeedsRegeneration = SSHPrincipal(struct {
-	Node          StableNodeID
-	NodeIP        string
-	UserLogin     string
-	Any           bool
-	UnusedPubKeys []string
+	Node      StableNodeID
+	NodeIP    string
+	UserLogin string
+	Any       bool
+	PubKeys   []string
 }{})
 
 // Clone makes a deep copy of ControlDialPlan.

tailcfg/tailcfg_view.go

@@ -1260,21 +1260,19 @@ func (v *SSHPrincipalView) UnmarshalJSON(b []byte) error {
 	return nil
 }
 
-func (v SSHPrincipalView) Node() StableNodeID { return v.ж.Node }
-func (v SSHPrincipalView) NodeIP() string     { return v.ж.NodeIP }
-func (v SSHPrincipalView) UserLogin() string  { return v.ж.UserLogin }
-func (v SSHPrincipalView) Any() bool          { return v.ж.Any }
-func (v SSHPrincipalView) UnusedPubKeys() views.Slice[string] {
-	return views.SliceOf(v.ж.UnusedPubKeys)
-}
+func (v SSHPrincipalView) Node() StableNodeID           { return v.ж.Node }
+func (v SSHPrincipalView) NodeIP() string               { return v.ж.NodeIP }
+func (v SSHPrincipalView) UserLogin() string            { return v.ж.UserLogin }
+func (v SSHPrincipalView) Any() bool                    { return v.ж.Any }
+func (v SSHPrincipalView) PubKeys() views.Slice[string] { return views.SliceOf(v.ж.PubKeys) }
 
 // A compilation failure here means this code must be regenerated, with the command at the top of this file.
 var _SSHPrincipalViewNeedsRegeneration = SSHPrincipal(struct {
-	Node          StableNodeID
-	NodeIP        string
-	UserLogin     string
-	Any           bool
-	UnusedPubKeys []string
+	Node      StableNodeID
+	NodeIP    string
+	UserLogin string
+	Any       bool
+	PubKeys   []string
 }{})
 
 // View returns a readonly view of ControlDialPlan.

types/bools/bools.go

@@ -1,28 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Package bools contains the [Compare] and [Select] functions.
-package bools
-
-// Compare compares two boolean values as if false is ordered before true.
-func Compare[T ~bool](x, y T) int {
-	switch {
-	case x == false && y == true:
-		return -1
-	case x == true && y == false:
-		return +1
-	default:
-		return 0
-	}
-}
-
-// IfElse is a ternary operator that returns trueVal if condExpr is true
-// otherwise it returns falseVal.
-// IfElse(c, a, b) is roughly equivalent to (c ? a : b) in languages like C.
-func IfElse[T any](condExpr bool, trueVal T, falseVal T) T {
-	if condExpr {
-		return trueVal
-	} else {
-		return falseVal
-	}
-}

types/bools/compare.go

@@ -0,0 +1,17 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Package bools contains the bools.Compare function.
+package bools
+
+// Compare compares two boolean values as if false is ordered before true.
+func Compare[T ~bool](x, y T) int {
+	switch {
+	case x == false && y == true:
+		return -1
+	case x == true && y == false:
+		return +1
+	default:
+		return 0
+	}
+}

types/bools/compare_test.go

@@ -19,12 +19,3 @@ func TestCompare(t *testing.T) {
 		t.Errorf("Compare(true, true) = %v, want 0", got)
 	}
 }
-
-func TestIfElse(t *testing.T) {
-	if got := IfElse(true, 0, 1); got != 0 {
-		t.Errorf("IfElse(true, 0, 1) = %v, want 0", got)
-	}
-	if got := IfElse(false, 0, 1); got != 1 {
-		t.Errorf("IfElse(false, 0, 1) = %v, want 1", got)
-	}
-}

types/iox/io.go

@@ -1,23 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-// Package iox provides types to implement [io] functionality.
-package iox
-
-// TODO(https://go.dev/issue/21670): Deprecate or remove this functionality
-// once the Go language supports implementing an 1-method interface directly
-// using a function value of a matching signature.
-
-// ReaderFunc implements [io.Reader] using the underlying function value.
-type ReaderFunc func([]byte) (int, error)
-
-func (f ReaderFunc) Read(b []byte) (int, error) {
-	return f(b)
-}
-
-// WriterFunc implements [io.Writer] using the underlying function value.
-type WriterFunc func([]byte) (int, error)
-
-func (f WriterFunc) Write(b []byte) (int, error) {
-	return f(b)
-}

types/iox/io_test.go

@@ -1,39 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package iox
-
-import (
-	"bytes"
-	"io"
-	"testing"
-	"testing/iotest"
-
-	"tailscale.com/util/must"
-)
-
-func TestCopy(t *testing.T) {
-	const testdata = "the quick brown fox jumped over the lazy dog"
-	src := testdata
-	bb := new(bytes.Buffer)
-	if got := must.Get(io.Copy(bb, ReaderFunc(func(b []byte) (n int, err error) {
-		n = copy(b[:min(len(b), 7)], src)
-		src = src[n:]
-		if len(src) == 0 {
-			err = io.EOF
-		}
-		return n, err
-	}))); int(got) != len(testdata) {
-		t.Errorf("copy = %d, want %d", got, len(testdata))
-	}
-	var dst []byte
-	if got := must.Get(io.Copy(WriterFunc(func(b []byte) (n int, err error) {
-		dst = append(dst, b...)
-		return len(b), nil
-	}), iotest.OneByteReader(bb))); int(got) != len(testdata) {
-		t.Errorf("copy = %d, want %d", got, len(testdata))
-	}
-	if string(dst) != testdata {
-		t.Errorf("copy = %q, want %q", dst, testdata)
-	}
-}

util/dnsname/dnsname.go

@@ -5,9 +5,9 @@
 package dnsname
 
 import (
+	"errors"
+	"fmt"
 	"strings"
-
-	"tailscale.com/util/vizerror"
 )
 
 const (
@@ -36,7 +36,7 @@ func ToFQDN(s string) (FQDN, error) {
 		totalLen += 1 // account for missing dot
 	}
 	if totalLen > maxNameLength {
-		return "", vizerror.Errorf("%q is too long to be a DNS name", s)
+		return "", fmt.Errorf("%q is too long to be a DNS name", s)
 	}
 
 	st := 0
@@ -54,7 +54,7 @@ func ToFQDN(s string) (FQDN, error) {
 		//
 		// See https://github.com/tailscale/tailscale/issues/2024 for more.
 		if len(label) == 0 || len(label) > maxLabelLength {
-			return "", vizerror.Errorf("%q is not a valid DNS label", label)
+			return "", fmt.Errorf("%q is not a valid DNS label", label)
 		}
 		st = i + 1
 	}
@@ -97,23 +97,23 @@ func (f FQDN) Contains(other FQDN) bool {
 // ValidLabel reports whether label is a valid DNS label.
 func ValidLabel(label string) error {
 	if len(label) == 0 {
-		return vizerror.New("empty DNS label")
+		return errors.New("empty DNS label")
 	}
 	if len(label) > maxLabelLength {
-		return vizerror.Errorf("%q is too long, max length is %d bytes", label, maxLabelLength)
+		return fmt.Errorf("%q is too long, max length is %d bytes", label, maxLabelLength)
 	}
 	if !isalphanum(label[0]) {
-		return vizerror.Errorf("%q is not a valid DNS label: must start with a letter or number", label)
+		return fmt.Errorf("%q is not a valid DNS label: must start with a letter or number", label)
 	}
 	if !isalphanum(label[len(label)-1]) {
-		return vizerror.Errorf("%q is not a valid DNS label: must end with a letter or number", label)
+		return fmt.Errorf("%q is not a valid DNS label: must end with a letter or number", label)
 	}
 	if len(label) < 2 {
 		return nil
 	}
 	for i := 1; i < len(label)-1; i++ {
 		if !isdnschar(label[i]) {
-			return vizerror.Errorf("%q is not a valid DNS label: contains invalid character %q", label, label[i])
+			return fmt.Errorf("%q is not a valid DNS label: contains invalid character %q", label, label[i])
 		}
 	}
 	return nil