Add Go tests that drive a real headless Chromium (via chromedp) against
the built cmd/tsconnect/pkg/ artifact and verify the @tailscale/connect
public API surface end-to-end. The package has not been republished in
three years, in part because no test exercises the produced artifact at
runtime — only tsc --noEmit and a Go build run in CI.
TestCreateIPN loads pkg.js into the browser, calls createIPN with a junk
auth key, and asserts that pkg.createIPN / pkg.runSSHSession are
functions and that createIPN() returns an IPN with the documented
run/login/logout/ssh/fetch methods. No control-plane traffic.
TestFetchTailnetPeer stands up a full local tailnet (testcontrol +
DERP + a tsnet.Server peer) and verifies that the browser-side WASM
client can join over WebSocket-noise to the same control, connect to
DERP over WSS, and then ipn.fetch() an HTTP service hosted on the tsnet
peer through the tailnet. The test asserts the response body matches a
known string. Browser state transitions are logged: NoState -> NeedsLogin
-> Starting -> Running.
Tests are opt-in via --run-headless-browser-tests (matching the existing
--run-vm-tests pattern in tstest/natlab/vmtest) so they never fire in
casual `go test ./...` runs. When the flag is set, a test is skipped if
cmd/tsconnect/pkg/ has not been built, and fails with t.Error if no
chromium binary is found on $PATH (honoring $CHROME_BIN as an override).
findChromium also falls back to /Applications/Google Chrome.app and
/Applications/Chromium.app on darwin, since macOS Chrome's executable
lives inside an .app bundle and is not on $PATH by default. The
.github/workflows/test.yml wasm job is extended to install
google-chrome-stable and run the tests with the flag after build-pkg.
To prevent silently testing a stale pkg/main.wasm (built from an older
checkout than the rest of the test invocation), build-pkg now writes
pkg/build-info.json recording the sha256 of the raw (pre-wasm-opt)
go-build output. The test does its own `go build` of
cmd/tsconnect/wasm with the same -tags/-trimpath/-ldflags (factored
into a new cmd/tsconnect/wasmbuild package shared by both call sites)
and t.Fatalfs with a "rebuild" instruction on mismatch. Cost is
near-zero because the Go build cache from the prior build-pkg makes
the rebuild a cache hit.
The new wasmbuild package also replaces cmd/tsconnect's hardcoded -tags
string with a minimal-feature-set computation. wasmbuild.Keep names the
small set of feature/featuretags entries the browser client actually
needs (netstack, logtail, dns, health, c2n, ipnbus); wasmbuild.Tags()
emits a ts_omit_<f> for every other
omittable feature in feature/featuretags.Features, with transitive deps
expanded via featuretags.Requires. An init() panics if Keep references
a feature unknown to feature/featuretags so a rename there fails
loudly. Net effect on size: 32M raw / 9.4M brotli before this change,
25M raw / 4.4M brotli after — vs the last-published 1.39.98 at 21M /
3.8M. The transitive package-import graph is unchanged (176
tailscale.com/* packages either way): featuretags omits eliminate
dead code via `const HasX = false`, not imports. Trimming the import
graph would require a separate, larger refactor splitting interface
packages by build tag.
Writing TestFetchTailnetPeer surfaced several real issues, all fixed
here:
* cmd/tsconnect built the wasm with the nethttpomithttp2 tag, but
control/ts2021 (since commit 1d93bdce2, "control/controlclient:
remove x/net/http2, use net/http", Oct 2025) requires HTTP/2 from
net/http's bundled implementation. With nethttpomithttp2 set, the
bundle is excluded and the wasm client cannot speak HTTP/2 to any
control plane, including production. Drop the tag. Wasm size grows
~1 MB raw / ~300 KB brotli (more than offset by the feature
pruning above). The last published @tailscale/connect (1.39.98,
early 2023) pre-dates the regression, which is why no consumer has
reported the breakage.
* tstest/integration/testcontrol.Server's /ts2021 noise upgrade
endpoint rejected anything but POST. WebSocket clients (the only
transport available to browser-WASM) come in as GET. Allow both;
the controlhttp AcceptHTTP path dispatches on the Upgrade header,
so the websocket library still enforces GET for WS upgrades.
This matches production, where the same controlhttpserver.AcceptHTTP
routes purely on the Upgrade header without checking method.
* derp/derphttp's urlString built the DERP URL from node.HostName
only, dropping node.DERPPort. Non-WS clients use a separate code
path (connectToHost) that honors DERPPort, but WebSocket-only
clients (browser-WASM) went through urlString and so could not
reach a DERP running on any port other than 443. Include the port
when it differs from the scheme default.
Also move addWebSocketSupport from cmd/derper (where it was main-only)
to derp/derpserver.AddWebSocketSupport so tstest/integration.RunDERPAndSTUN
can wrap its DERP handler with WebSocket support — without that, the
test DERP would not accept the browser's wss connection.
Fixes#9394
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: Iff9cdee303e3b239924249b5bffb2fd04e02f391
Server.clientsAtomic was introduced in 6b729795c3 as a lock-free
mirror of Server.clients to skip Server.mu on the packet send hot
path. This drops the non-concurrent map and makes all the existing
callers of the old plain map just use the concurrent map, but still
holding Server.mu.
BenchmarkLookupDestHashTrie is unchanged at ~2ns/op.
Fixes#19726
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: I0894e4d86914d152b9b5fef969a3184bcb96f678
Replace the process-global Server.mu lookup in the packet send hot path
with a global hashtriemap mirror of local clientSet entries. The
authoritative clients map remains guarded by Server.mu; clientsAtomic is
only a lock-free fast path for active local clients.
Misses, stale inactive client sets, duplicate accounting, and mesh
forwarding still fall back to lookupDestUncached. This avoids taking
Server.mu for the common local active-client send path, at the cost of
adding one global concurrent map that mirrors Server.clients for local
peers.
The benchmark uses four destination peers. The before run sets
TS_DEBUG_DERP_DISABLE_PEER_HASHTRIE=true to force the old mutex lookup
path; the after run uses the hashtrie fast path.
goos: linux
goarch: amd64
pkg: tailscale.com/derp/derpserver
cpu: Intel(R) Xeon(R) 6975P-C
│ before │ after │
│ sec/op │ sec/op vs base │
LookupDestHashTrie-16 176.050n ± 1% 1.904n ± 6% -98.92% (p=0.000 n=10)
│ before │ after │
│ B/op │ B/op vs base │
LookupDestHashTrie-16 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹
¹ all samples are equal
│ before │ after │
│ allocs/op │ allocs/op vs base │
LookupDestHashTrie-16 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹
¹ all samples are equal
Updates #3560 (very indirectly, historically)
Updates #19713 (as an alternative to that PR)
Change-Id: Ifb72e5c9854ad00e938cd24c6ab9c27312f297e8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
As of 0e9f9e2bd it is possible to have an infinity per-client limit,
with finite global.
Updates tailscale/corp#40962
Signed-off-by: Jordan Whited <jordan@tailscale.com>
This commit enables the operator to set a global rate limit without any
per-client.
Updates tailscale/corp#40962
Signed-off-by: Jordan Whited <jordan@tailscale.com>
Expvars track count of rate limiters exceeding their threshold.
Covers (1) global rate limiter and (2) total of local rate limiters.
Also publish optional rate-limit metrics during ExpVar() call
if -rate-config is specified. Fixes current rate-limit metrics
being published outside of "derp" in /debug/vars.
Updates tailscale/corp#38509
Change-Id: Ic7f5a1e890d0d7d3d7b679daa4b5f8926a6a6964
Signed-off-by: Alex Valiushko <alexvaliushko@tailscale.com>
By adding a server-global parent bucket. Per-client rate limiting is
subject to the parent bucket if global rate limiting is enabled.
This implementation is experimental, and all related APIs should be
considered unstable.
Updates tailscale/corp#40291
Signed-off-by: Jordan Whited <jordan@tailscale.com>
And cap WaitN calls to prevent token bucket errors. Frame length is
inclusive of DERP key for FrameSendPacket frames.
Updates tailscale/corp#40171
Signed-off-by: Jordan Whited <jordan@tailscale.com>
Add a --rate-config flag pointing to a JSON file for per-client receive
rate limits (bytes/sec and burst bytes). The config is reloaded on SIGHUP,
updating all existing client connections live. The --per-client-rate-limit
and --per-client-rate-burst flags are removed in favor of the config file.
In derpserver, rate limiting uses an atomic.Pointer[xrate.Limiter] per
client: nil when unlimited or mesh (zero overhead), non-nil when
rate-limited.
Document that clientSet.activeClient Store operations require Server.mu.
Updates tailscale/corp#38509
Signed-off-by: Mike O'Driscoll <mikeo@tailscale.com>
Add server-side per-client bandwidth enforcement using TCP backpressure.
When configured, the server calls WaitN after reading each DERP frame,
which delays the next read, fills the TCP receive buffer, shrinks
the TCP window, and naturally throttles the sender — no packets are dropped.
- Rate limiting is on the receive (inbound) side, which is what an abusive
client controls
- Mesh peers are exempt since they are trusted infrastructure
- The burst size is at least MaxPacketSize (64KB) to ensure a
single max-size frame can always be processed
Also refactors sclient to store a context.Context directly instead of a
done channel, which simplifies the rate limiter's WaitN call.
Flags added to cmd/derper:
--per-client-rate-limit (bytes/sec, default 0 = unlimited)
--per-client-rate-burst (bytes, default 0 = 2x rate limit)
Example for 10Mbps: --per-client-rate-limit=1250000
Updates #38509
Signed-off-by: Mike O'Driscoll <mikeo@tailscale.com>
Replace byte-at-a-time ReadByte loops with Peek+Discard in the DERP
read path. Peek returns a slice into bufio's internal buffer without
allocating, and Discard advances the read pointer without copying.
Introduce util/bufiox with a BufferedReader interface and ReadFull
helper that uses Peek+copy+Discard as an allocation-free alternative
to io.ReadFull.
- derp.ReadFrameHeader: replace 5× ReadByte with Peek(5)+Discard(5),
reading the frame type and length directly from the peeked slice.
Remove now-unused readUint32 helper.
name old ns/op new ns/op speedup
ReadFrameHeader-8 24.2 12.4 ~2x
(0 allocs/op in both)
- key.NodePublic.ReadRawWithoutAllocating: replace 32× ReadByte with
bufiox.ReadFull. Addresses the "Dear future" comment about switching
away from byte-at-a-time reads once a non-escaping alternative exists.
name old ns/op new ns/op speedup
NodeReadRawWithoutAllocating-8 140 43.6 ~3.2x
(0 allocs/op in both)
- derpserver.handleFramePing: replace io.ReadFull with bufiox.ReadFull.
Updates tailscale/corp#38509
Signed-off-by: Mike O'Driscoll <mikeo@tailscale.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>
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>
Adds an observation point that may identify potentially abusive traffic
patterns at outlier values.
Updates tailscale/corp#24681
Signed-off-by: James Tucker <james@tailscale.com>
PR #17258 extracted `derp.Server` into `derp/derpserver.Server`.
This followup patch adds the following cleanups:
1. Rename `derp_server*.go` files to `derpserver*.go` to match
the package name.
2. Rename the `derpserver.NewServer` constructor to `derpserver.New`
to reduce stuttering.
3. Remove the unnecessary `derpserver.Conn` type alias.
Updates #17257
Updates #cleanup
Signed-off-by: Simon Law <sfllaw@tailscale.com>
This exports a number of things from the derp (generic + client) package
to be used by the new derpserver package, as now used by cmd/derper.
And then enough other misc changes to lock in that cmd/tailscaled can
be configured to not bring in tailscale.com/client/local. (The webclient
in particular, even when disabled, was bringing it in, so that's now fixed)
Fixes#17257
Change-Id: I88b6c7958643fb54f386dd900bddf73d2d4d96d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
