version/distro: identify iStoreOS as a distro.

A NAS system based on OpenWRT: https://www.istoreos.com/

Updates https://github.com/tailscale/corp/issues/14033

Signed-off-by: Denton Gentry <dgentry@tailscale.com>

hostinfo/hostinfo_linux.go

@@ -95,6 +95,8 @@ func linuxVersionMeta() (meta versionMeta) {
 		propFile = "/etc.defaults/VERSION"
 	case distro.OpenWrt:
 		propFile = "/etc/openwrt_release"
+	case distro.IStoreOS:
+		propFile = "/etc/openwrt_release"
 	case distro.Unraid:
 		propFile = "/etc/unraid-version"
 	case distro.WDMyCloud:
@@ -153,7 +155,7 @@ func linuxVersionMeta() (meta versionMeta) {
 	switch dist {
 	case distro.Synology:
 		meta.DistroVersion = m["productversion"]
-	case distro.OpenWrt:
+	case distro.OpenWrt, distro.IStoreOS:
 		meta.DistroVersion = m["DISTRIB_RELEASE"]
 	case distro.Unraid:
 		meta.DistroVersion = m["version"]

version/distro/distro.go

@@ -31,6 +31,7 @@ const (
 	WDMyCloud = Distro("wdmycloud")
 	Unraid    = Distro("unraid")
 	Alpine    = Distro("alpine")
+	IStoreOS  = Distro("istoreos")
 )
 
 var distro lazy.SyncValue[Distro]
@@ -96,6 +97,8 @@ func linuxDistro() Distro {
 		return Unraid
 	case have("/etc/alpine-release"):
 		return Alpine
+	case have("/usr/libexec/istore"):
+		return IStoreOS
 	}
 	return ""
 }