tailscale/wgengine, branch debug-testwrapper

ipn/localapi: stop logging "broken pipe" errors (#18487)

2026-01-27T00:41:03Z

The Tailscale CLI has some methods to watch the IPN bus for messages, say, the current netmap (`tailscale debug netmap`). The Tailscale daemon supports this using a streaming HTTP response. Sometimes, the client can close its connection abruptly -- due to an interruption, or in the case of `debug netmap`, intentionally after consuming one message. If the server daemon is writing a response as the client closes its end of the socket, the daemon typically encounters a "broken pipe" error. The "Watch IPN Bus" handler currently logs such errors after they're propagated by a JSON encoding/writer helper. Since the Tailscale CLI nominally closes its socket with the daemon in this slightly ungraceful way (viz. `debug netmap`), stop logging these broken pipe errors as far as possible. This will help avoid confounding users when they scan backend logs. Updates #18477 Signed-off-by: Amal Bansode

all: remove AUTHORS file and references to it

2026-01-23T23:49:45Z

This file was never truly necessary and has never actually been used in the history of Tailscale's open source releases. A Brief History of AUTHORS files --- The AUTHORS file was a pattern developed at Google, originally for Chromium, then adopted by Go and a bunch of other projects. The problem was that Chromium originally had a copyright line only recognizing Google as the copyright holder. Because Google (and most open source projects) do not require copyright assignemnt for contributions, each contributor maintains their copyright. Some large corporate contributors then tried to add their own name to the copyright line in the LICENSE file or in file headers. This quickly becomes unwieldy, and puts a tremendous burden on anyone building on top of Chromium, since the license requires that they keep all copyright lines intact. The compromise was to create an AUTHORS file that would list all of the copyright holders. The LICENSE file and source file headers would then include that list by reference, listing the copyright holder as "The Chromium Authors". This also become cumbersome to simply keep the file up to date with a high rate of new contributors. Plus it's not always obvious who the copyright holder is. Sometimes it is the individual making the contribution, but many times it may be their employer. There is no way for the proejct maintainer to know. Eventually, Google changed their policy to no longer recommend trying to keep the AUTHORS file up to date proactively, and instead to only add to it when requested: https://opensource.google/docs/releasing/authors. They are also clear that: > Adding contributors to the AUTHORS file is entirely within the > project's discretion and has no implications for copyright ownership. It was primarily added to appease a small number of large contributors that insisted that they be recognized as copyright holders (which was entirely their right to do). But it's not truly necessary, and not even the most accurate way of identifying contributors and/or copyright holders. In practice, we've never added anyone to our AUTHORS file. It only lists Tailscale, so it's not really serving any purpose. It also causes confusion because Tailscalars put the "Tailscale Inc & AUTHORS" header in other open source repos which don't actually have an AUTHORS file, so it's ambiguous what that means. Instead, we just acknowledge that the contributors to Tailscale (whoever they are) are copyright holders for their individual contributions. We also have the benefit of using the DCO (developercertificate.org) which provides some additional certification of their right to make the contribution. The source file changes were purely mechanical with: git ls-files | xargs sed -i -e 's/\(Tailscale Inc &\) AUTHORS/\1 contributors/g' Updates #cleanup Change-Id: Ia101a4a3005adb9118051b3416f5a64a4a45987d Signed-off-by: Will Norris

tsnet: add support for a user-supplied tun.Device

2026-01-23T01:29:55Z

tsnet users can now provide a tun.Device, including any custom implementation that conforms to the interface. netstack has a new option CheckLocalTransportEndpoints that when used alongside a TUN enables netstack listens and dials to correctly capture traffic associated with those sockets. tsnet with a TUN sets this option, while all other builds leave this at false to preserve existing performance. Updates #18423 Signed-off-by: James Tucker

wgengine: send disco key via TSMP on first contact (#18215)

2026-01-22T19:50:24Z

When we have not yet communicated with a peer, send a TSMPDiscoAdvertisement to let the peer know of our disco key. This is in most cases redundant, but will allow us to set up direct connections when the client cannot access control. Some parts taken from: #18073 Updates #12639 Signed-off-by: Claus Lensbøl

ipn,ipn/local: always accept routes for Tailscale Services (cgnat range) (#18173)

2026-01-14T18:20:00Z

Updates #18198 Signed-off-by: chaosinthecrd Co-authored-by: James Tucker

wgengine/magicsock: add home DERP region usermetric (#18062)

2026-01-09T21:47:56Z

Expose the node's home DERP region ID as a Prometheus gauge via the usermetrics endpoint. Fixes #18061 Signed-off-by: Raj Singh

wgengine/magicsock: extract IMDS utilities into a standalone package (#18334)

2026-01-07T05:58:52Z

Moves magicksock.cloudInfo into util/cloudinfo with minimal changes. Updates #17796 Change-Id: I83f32473b9180074d5cdbf00fa31e5b3f579f189 Signed-off-by: Alex Valiushko

net/netmon, wgengine/userspace: purge ChangeDelta.Major and address TODOs (#17823)

2025-12-17T17:32:40Z

updates tailscale/corp#33891 Addresses several older the TODO's in netmon. This removes the Major flag precomputes the ChangeDelta state, rather than making consumers of ChangeDeltas sort that out themselves. We're also seeing a lot of ChangeDelta's being flagged as "Major" when they are not interesting, triggering rebinds in wgengine that are not needed. This cleans that up and adds a host of additional tests. The dependencies are cleaned, notably removing dependency on netmon itself for calculating what is interesting, and what is not. This includes letting individual platforms set a bespoke global "IsInterestingInterface" function. This is only used on Darwin. RebindRequired now roughly follows how "Major" was historically calculated but includes some additional checks for various uninteresting events such as changes in interface addresses that shouldn't trigger a rebind. This significantly reduces thrashing (by roughly half on Darwin clients which switching between nics). The individual values that we roll into RebindRequired are also exposed so that components consuming netmap.ChangeDelta can ask more targeted questions. Signed-off-by: Jonathan Nobels

net/{packet,tstun},wgengine: update disco key when receiving via TSMP (#18158)

2025-12-10T19:27:20Z

When receiving a TSMPDiscoAdvertisement from peer, update the discokey for said peer. Some parts taken from: https://github.com/tailscale/tailscale/pull/18073/ Updates #12639 Co-authored-by: James Tucker

net/dns: retrample resolve.conf when another process has trampled it (#18069)

2025-12-09T19:55:26Z

When using the resolve.conf file for setting DNS, it is possible that some other services will trample the file and overwrite our set DNS server. Experiments has shown this to be a racy error depending on how quickly processes start. Make an attempt to trample back the file a limited number of times if the file is changed. Updates #16635 Signed-off-by: Claus Lensbøl