It was previously possible for two different Windows users to connect
to the IPN server at once, but it didn't really work. They mostly
stepped on each other's toes and caused chaos.
Now only one can control it, but it can be active for everybody else.
Necessary dependency step for Windows server/headless mode (#275)
While here, finish wiring up the HTTP status page on Windows, now that
all the dependent pieces are available.
Also, bit of behavior change: on non-nil err but expired context,
don't reset the consecutive failure count. I don't think the old
behavior was intentional.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
So a backend in server-an-error state (as used by Windows) can try to
create a new Engine again each time somebody re-connects, relaunching
the GUI app.
(The proper fix is actually fixing Windows issues, but this makes things better
in the short term)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
It's just a config wrapper that passes "use less memory at the
expense of compression" parameters by default, so that we don't
accidentally construct resource-hungry (de)compressors.
Also includes a benchmark that measures the memory cost of the
small variants vs. the stock variants. The savings are significant
on both compressors (~8x less memory) and decompressors (~1.4x less,
not including the savings from the significantly smaller
window on the compression side - with those savings included it's
more like ~140x smaller).
BenchmarkSmallEncoder-8 56174 19354 ns/op 31 B/op 0 allocs/op
BenchmarkSmallEncoderWithBuild-8 2900 382940 ns/op 1746547 B/op 36 allocs/op
BenchmarkStockEncoder-8 48921 25761 ns/op 286 B/op 0 allocs/op
BenchmarkStockEncoderWithBuild-8 426 2630241 ns/op 13843842 B/op 124 allocs/op
BenchmarkSmallDecoder-8 123814 9344 ns/op 0 B/op 0 allocs/op
BenchmarkSmallDecoderWithBuild-8 41547 27455 ns/op 27694 B/op 31 allocs/op
BenchmarkStockDecoder-8 129832 9417 ns/op 1 B/op 0 allocs/op
BenchmarkStockDecoderWithBuild-8 25561 51751 ns/op 39607 B/op 92 allocs/op
Signed-off-by: David Anderson <danderson@tailscale.com>
The zstd library treats that limit as a hard cap on decompressed
size, in the mode we're using it, rather than a window size.
Signed-off-by: David Anderson <danderson@tailscale.com>
The compressed blobs we send back and forth are small and infrequent,
which doesn't justify the 8MB * GOMAXPROCS memory that was being
allocated. This was the overwhelming majority of memory use in
tailscaled. On my system it goes from ~100M RSS to ~15M RSS (which is
still suspiciously high, but we can worry about that more later).
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
If a test calls log.Printf, 'go test' horrifyingly rearranges the
output to no longer be in chronological order, which makes debugging
virtually impossible. Let's stop that from happening by making
log.Printf panic if called from any module, no matter how deep, during
tests.
This required us to change the default error handler in at least one
http.Server, as well as plumbing a bunch of logf functions around,
especially in magicsock and wgengine, but also in logtail and backoff.
To add insult to injury, 'go test' also rearranges the output when a
parent test has multiple sub-tests (all the sub-test's t.Logf is always
printed after all the parent tests t.Logf), so we need to screw around
with a special Logf that can point at the "current" t (current_t.Logf)
in some places. Probably our entire way of using subtests is wrong,
since 'go test' would probably like to run them all in parallel if you
called t.Parallel(), but it definitely can't because the're all
manipulating the shared state created by the parent test. They should
probably all be separate toplevel tests instead, with common
setup/teardown logic. But that's a job for another time.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
This removes the need for go-cmp, which is extremely bloaty so we had
to leave it out of iOS. As a result, we had also left it out of macOS,
and so we didn't print netmap diffs at all on darwin-based platforms.
Oops.
As a bonus, the output format of the new function is way better.
Minor oddity: because I used the dumbest possible diff algorithm, the
sort order is a bit dumb. We print all "removed" lines and then print
all "added" lines, rather than doing the usual diff-like thing of
interspersing them. This probably doesn't matter (maybe it's an
improvement).
We can't rely on a frontend to provide a control
server URL, so this naturally belongs in server-persisted
state.
Signed-off-by: David Anderson <dave@natulte.net>
On unix, we want to provide a full path to the desired unix socket.
On windows, currently we want to provide a TCP port, but someday
we'll also provide a "path-ish" object for a named pipe.
For now, simplify the API down to exactly a path and a TCP port.
Signed-off-by: David Anderson <dave@natulte.net>
With this change, tailscaled can be restarted and reconnect
without interaction from `tailscale`, and `tailscale` is merely
there to provide login assistance and adjust preferences.
Signed-off-by: David Anderson <dave@natulte.net>
It was previously used by the MacOS client, but it now does
something different. ipnserver should never obey a client's
request to exit.
Signed-off-by: David Anderson <dave@natulte.net>
The store is passed-in by callers of NewLocalBackend and
ipnserver.Run, but currently all callers are hardcoded to
an in-memory store. The store is unused.
Signed-Off-By: David Anderson <dave@natulte.net>
The linter is strictly correct, but the code is structured
this way to avoid variable shadowing problems in the following
for loop. The context doesn't leak.
Staticcheck is correctly pointing out that this code is hard to
follow. However, this chunk of code is in service of enforcing
one frontend <> one backend, and we want to remove that limitation.
So, we'll just ignore the lint warning until this entire piece of
code goes away.
Signed-off-by: David Anderson <dave@natulte.net>
