5c1738fd56
Add a vmtest TestExitNode that brings up a client, two exit nodes, and a non-Tailscale webserver, each on its own NAT'd vnet network with a distinct WAN IP. The test cycles the client's exit node setting between off, exit1, and exit2 and asserts that the webserver echoes the expected post-NAT source IP for each. Three pieces were needed to make this work: vnet now forwards TCP between simulated networks at the packet level, mirroring the existing UDP path. When a guest VM sends TCP to another simulated network's WAN IP, the source network's gateway rewrites src via doNATOut and routeTCPPacket hands the packet off to the destination network, which rewrites dst via doNATIn and writes the rewritten frame onto the destination LAN. The TCP stacks of the two guest VM kernels talk end-to-end; vnet just NATs the IP/port headers in flight, so all TCP semantics (handshakes, options, sequence numbers, payload) are preserved without a gvisor TCP termination in the middle. Adds a focused TestInterNetworkTCP that exercises this path without any Tailscale machinery. cmd/tta binds its outbound dial to the default route's interface using SO_BINDTODEVICE. Without that, the moment tailscaled installs 0.0.0.0/0 → tailscale0 in response to setting an exit node, TTA's existing TCP connection to test-driver gets rerouted through the exit node. From the test driver's perspective the connection's packets then arrive with the exit node's WAN IP as the source rather than the client's, so they don't match the existing flow and the connection is dead — manifesting in the test as a hang on EditPrefs (which had actually completed in milliseconds on the daemon side, but whose response never made it back). Pinning the socket to the underlying NIC keeps TTA's agent connection on a real interface regardless of any policy routing tailscaled installs later. We bind rather than carry the Tailscale bypass fwmark because the fwmark approach is conditional on tailscaled having configured SO_MARK-based policy routing, while binding is unconditional. vmtest grows an Env.SetExitNode helper that sets ExitNodeIP via EditPrefs through the agent, used by the new test. Updates #13038 Change-Id: I9fc8f91848b7aa2297ef3eaf71fed9d96056a024 Signed-off-by: Brad Fitzpatrick <bradfitz@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 1.26. (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.