Shutting down a socket's read side after its peer's FIN has arrived does
nothing on the wire and fails with ENOTCONN on macOS (and on Linux once
the socket reaches TIME_WAIT), so every cleanly half-closed connection
was logged as a failure and TestTCPHalfClose failed on macOS. Only
half-close the destination after EOF.
When one direction fails, one of the two sockets is dead. If the failure
was writing to it, the other direction is reading from that dead socket
and finishes on its own once it has drained what arrived before the
failure, so leave it alone rather than truncate the data. If the failure
was reading from it, the other direction may be blocked reading the live
peer, so close both connections to unblock it; nothing deliverable is
lost in that case.
Telling the two apart means wrapping the destination, which disables the
kernel splice fast path when both ends are bare TCP connections (about a
third of relay throughput on Linux loopback). That is accepted here: the
common userspace-networking and proxymux configurations wrap the
connections anyway, so they never had the fast path.
The regression was introduced by 027e249fcf (#21359), merged 2026-09-17.
Tested on Linux and on macOS 27 (arm64): the old test failed 49 of 50
runs on macOS; the new tests pass 200 iterations there and pass under
the race detector on Linux.
Fixes#21522
Updates #20883
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: I7c2e4a9d1b8f5e3c6a0d2f4b8e1c9a7d3f5b6e2c
Similar to #16462, when we are acting as a TCP proxy, we need to pass
through half-closes correctly since clients and servers will sometimes
close one direction of the connection and still rely on the other
direction working.
Fixes#20883.
Signed-off-by: Naman Sood <mail@nsood.in>
TestUDPConcurrent closed its UDP connection as soon as the send loop
finished, and then required that at least one reply had arrived. With
GOMAXPROCS=1 the send loop runs to completion before the proxy's relay
goroutines are scheduled at all, so the close discarded every response.
The test failed on all 20 runs of "go test -race -count=20 -cpu=1".
Wait for the first reply, with a 10 second timeout, before closing the
connection.
This also makes the test catch the race it was written for more often.
With the fix in 0301c7493 reverted, "-cpu=2" reports the race where it
previously reported none.
Fixes#21182
Signed-off-by: Brendan Creane <bcreane@gmail.com>
Serve copied the raw Server.Logf field into each Conn, so the UDP error
paths called a nil func instead of falling back to log.Printf. Conn
already holds the Server, so drop the duplicated field and log through
the server's method.
Fixes#21047
Signed-off-by: Brendan Creane <bcreane@gmail.com>
handleUDPRequest recorded the client's UDP source address in
Conn.udpClientAddr on the goroutine that reads from the client.
handleUDPResponse read the field to address the responses, and it runs
on a separate goroutine per target. Nothing synchronized the two.
Guard the field with syncs.MutexValue. The most recently written
address still wins, which is what the code did before.
TestUDPConcurrent keeps datagrams in flight to four targets at once.
Without the fix it reports the race on every run.
Fixes#21048
Signed-off-by: Brendan Creane <bcreane@gmail.com>
The SOCKS5 server checked the client-supplied username and password against the configured credentials with plain string equality, which returns on the first differing byte. In tsnet the password is a random 128-bit value that gates every dial out through the node, and the listener is on 127.0.0.1, so a local process can time the auth reject to recover it a byte at a time with unlimited attempts and no lockout. The LocalAPI sharing the same loopback listener already compares its credential with subtle.ConstantTimeCompare; do the same here for both fields, evaluating both so the username result does not gate whether the password is examined.
Updates #20998
Signed-off-by: basavaraj-sm05 <basavaraj@digiscrypt.com>
I omitted a lot of the min/max modernizers because they didn't
result in more clear code.
Some of it's older "for x := range 123".
Also: errors.AsType, any, fmt.Appendf, etc.
Updates #18682
Change-Id: I83a451577f33877f962766a5b65ce86f7696471c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Fix its/it's, who's/whose, wether/whether, missing apostrophes
in contractions, and other misspellings across the codebase.
Updates #cleanup
Change-Id: I20453b81a7aceaa14ea2a551abba08a2e7f0a1d8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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 <will@tailscale.com>
Key changes:
- No mutex for every udp package: replace syncs.Map with regular map for udpTargetConns
- Use socksAddr as map key for better type safety
- Add test for multi udp target
Updates #7581
Change-Id: Ic3d384a9eab62dcbf267d7d6d268bf242cc8ed3c
Signed-off-by: VimT <me@vimt.me>
This commit addresses an issue with the SOCKS5 UDP relay functionality
when using the --tun=userspace-networking option. Previously, UDP packets
were not being correctly routed into the Tailscale network in this mode.
Key changes:
- Replace single UDP connection with a map of connections per target
- Use c.srv.dial for creating connections to ensure proper routing
Updates #7581
Change-Id: Iaaa66f9de6a3713218014cf3f498003a7cac9832
Signed-off-by: VimT <me@vimt.me>
Conforms to RFC 1929.
To support Java HTTP clients via libtailscale, who offer no other
reliable hooks into their sockets.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This updates all source files to use a new standard header for copyright
and license declaration. Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.
This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.
Updates #6865
Signed-off-by: Will Norris <will@tailscale.com>
Start up a backend service, put a SOCKS5 server in front
of it, and verify that we can get data from the backend via
SOCKS5.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
Customer reported an issue where the connections were not closing, and
would instead just stay open. This commit makes it so that we close out
the connection regardless of what error we see. I've verified locally
that it fixes the issue, we should add a test for this.
Signed-off-by: Maisem Ali <maisem@tailscale.com>
For now this just deletes the net/socks5/tssocks implementation (and
the DNSMap stuff from wgengine/netstack) and moves it into net/tsdial.
Then initialize a Dialer early in tailscaled, currently only use for the
outbound and SOCKS5 proxies. It will be plumbed more later. Notably, it
needs to get down into the DNS forwarder for exit node DNS forwading
in netstack mode. But it will also absorb all the peerapi setsockopt
and netns Dial and tlsdial complexity too.
Updates #1713
Change-Id: Ibc6d56ae21a22655b2fa1002d8fc3f2b2ae8b6df
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And add a --socks5-server flag.
And fix a race in SOCKS5 replies where the response header was written
concurrently with the copy from the backend.
Co-authored with Naman Sood.
Updates #707
Updates #504
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Brad Fitzpatrick