6a275c01db
ClampMSSToPMTU only added a rule matching the output interface (-o tun / OIFNAME), which clamps the SYN forwarded out towards the tailnet peer but not the SYN-ACK that arrives on tun and is forwarded back towards the originating endpoint. As a result only one side of a forwarded handshake had its MSS clamped; the endpoint on the other side of the proxy kept advertising an MSS based on its own (larger) MTU. When path MTU discovery is broken (e.g. proxies created by the Tailscale Kubernetes operator, where tailscale0 has a 1280 MTU), the unclamped endpoint's large segments exceed the tun MTU and are silently dropped, causing TCP connections through proxy group pods to stall mid-stream on large payloads. The earlier proxy-group fix (#19686) wired ClampMSSToPMTU into the HA code paths but inherited this single-direction limitation, so connections could still hang. Add a second rule matching the input interface (-i tun / IIFNAME) in both the iptables and nftables runners so both directions of the forwarded handshake negotiate a PMTU-safe MSS. Updates #19812 Signed-off-by: Samy Djemaï <53857555+SamyDjemai@users.noreply.github.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 1.26. (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 commit-messages.md (or skim git log) for our commit message 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.