27033c6277
Fixes tailscale/corp#20677 Replaces the original attempt to rectify this (by injecting a netMon event) which was both heavy handed, and missed cases where the netMon event was "minor". On apple platforms, the fetching the interface's nameservers can and does return an empty list in certain situations. Apple's API in particular is very limiting here. The header hints at notifications for dns changes which would let us react ahead of time, but it's all private APIs. To avoid remaining in the state where we end up with no nameservers but we absolutely need them, we'll react to a lack of upstream nameservers by attempting to re-query the OS. We'll rate limit this to space out the attempts. It seems relatively harmless to attempt a reconfig every 5 seconds (triggered by an incoming query) if the network is in this broken state. Missing nameservers might possibly be a persistent condition (vs a transient error), but that would also imply that something out of our control is badly misconfigured. Tested by randomly returning [] for the nameservers. When switching between Wifi networks, or cell->wifi, this will randomly trigger the bug, and we appear to reliably heal the DNS state. Signed-off-by: Jonathan Nobels <jonathan@tailscale.com>
Tailscale
Private WireGuard® networks made easy
Overview
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, 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.
Other Tailscale repos 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/.
Using
We serve packages for a variety of distros and platforms at https://pkgs.tailscale.com.
Other clients
The macOS, iOS, and Windows clients use the code in this repository but additionally include small GUI wrappers. The GUI wrappers on non-open source platforms are themselves not open source.
Building
We always require the latest Go release, currently Go 1.22. (While we build releases with our Go fork, its use is not required.)
go install tailscale.com/cmd/tailscale{,d}
If you're packaging Tailscale for distribution, use build_dist.sh
instead, to burn commit IDs and version info into the binaries:
./build_dist.sh tailscale.com/cmd/tailscale
./build_dist.sh tailscale.com/cmd/tailscaled
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.
Bugs
Please file any issues about this code or the hosted service on the issue tracker.
Contributing
PRs welcome! But please file bugs. Commit messages should reference bugs.
We require 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.
About Us
Tailscale is primarily developed by the people at https://github.com/orgs/tailscale/people. For other contributors, see:
- https://github.com/tailscale/tailscale/graphs/contributors
- https://github.com/tailscale/tailscale-android/graphs/contributors
Legal
WireGuard is a registered trademark of Jason A. Donenfeld.