Commit Graph

264 Commits (9e5e4de2bcdaa1877606a471217374119a54f3db)

Author SHA1 Message Date
Brad Fitzpatrick eefee6f149 all: use cmpx.Or where it made sense
I left a few out where writing it explicitly was better
for various reasons.

Updates #8296

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
valscale 5ae786988c
derp: remove default logging of disconnecting clients (#8163)
~97% of the log messages derper outputs are related to the normal
non-error state of a client disconnecting in some manner. Add a
verbose logging feature that only logs these messages when enabled.

Fixes #8024

Signed-off-by: Val <valerie@tailscale.com>
1 year ago
Brad Fitzpatrick c1e6888fc7 derp: add a README.md with some docs
Updates #docs

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Mihai Parparita 7330aa593e all: avoid repeated default interface lookups
On some platforms (notably macOS and iOS) we look up the default
interface to bind outgoing connections to. This is both duplicated
work and results in logspam when the default interface is not available
(i.e. when a phone has no connectivity, we log an error and thus cause
more things that we will try to upload and fail).

Fixed by passing around a netmon.Monitor to more places, so that we can
use its cached interface state.

Fixes #7850
Updates #7621

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita edb02b63f8 net/sockstats: pass in logger to sockstats.WithSockStats
Using log.Printf may end up being printed out to the console, which
is not desirable. I noticed this when I was investigating some client
logs with `sockstats: trace "NetcheckClient" was overwritten by another`.
That turns to be harmless/expected (the netcheck client will fall back
to the DERP client in some cases, which does its own sockstats trace).

However, the log output could be visible to users if running the
`tailscale netcheck` CLI command, which would be needlessly confusing.

Updates tailscale/corp#9230

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
valscale 7bfb7744b7
derp,magicsock: add debug envknobs for HTTP and derp server name (#7744)
Make developing derp easier by:

1. Creating an envknob telling clients to use HTTP to connect to derp
servers, so devs don't have to acquire a valid TLS cert.

2. Creating an envknob telling clients which derp server to connect
to, so devs don't have to edit the ACLs in the admin console to add a
custom DERP map.

3. Explaining how the -dev and -a command lines args to derper
interact.

To use this:

1. Run derper with -dev.

2. Run tailscaled with TS_DEBUG_USE_DERP_HTTP=1 and
TS_DEBUG_USE_DERP_ADDR=localhost

This will result in the client connecting to derp via HTTP on port
3340.

Fixes #7700

Signed-off-by: Val <valerie@tailscale.com>
2 years ago
valscale 74eb99aed1
derp, derphttp, magicsock: send new unknown peer frame when destination is unknown (#7552)
* wgengine/magicsock: add envknob to send CallMeMaybe to non-existent peer

For testing older client version responses to the PeerGone packet format change.

Updates #4326

Signed-off-by: Val <valerie@tailscale.com>

* derp: remove dead sclient struct member replaceLimiter

Leftover from an previous solution to the duplicate client problem.

Updates #2751

Signed-off-by: Val <valerie@tailscale.com>

* derp, derp/derphttp, wgengine/magicsock: add new PeerGone message type Not Here

Extend the PeerGone message type by adding a reason byte. Send a
PeerGone "Not Here" message when an endpoint sends a disco message to
a peer that this server has no record of.

Fixes #4326

Signed-off-by: Val <valerie@tailscale.com>

---------

Signed-off-by: Val <valerie@tailscale.com>
2 years ago
Anton Tolchanov 654b5a0616 derp: add optional debug logging for prober clients
This allows tracking packet flow via logs for prober clients. Note that
the new sclient.debug() function is called on every received packet, but
will do nothing for most clients.

I have adjusted sclient logging to print public keys in short format
rather than full. This takes effect even for existing non-debug logging
(mostly client disconnect messages).

Example logs for a packet being sent from client [SbsJn] (connected to
derper [dM2E3]) to client [10WOo] (connected to derper [AVxvv]):

```
derper [dM2E3]:
derp client 10.0.0.1:35470[SbsJn]: register single client mesh("10.0.1.1"): 4 peers
derp client 10.0.0.1:35470[SbsJn]: read frame type 4 len 40 err <nil>
derp client 10.0.0.1:35470[SbsJn]: SendPacket for [10WOo], forwarding via <derphttp_client.Client [AVxvv] url=https://10.0.1.1/derp>: <nil>
derp client 10.0.0.1:35470[SbsJn]: read frame type 0 len 0 err EOF
derp client 10.0.0.1:35470[SbsJn]: read EOF
derp client 10.0.0.1:35470[SbsJn]: sender failed: context canceled
derp client 10.0.0.1:35470[SbsJn]: removing connection

derper [AVxvv]:
derp client 10.0.1.1:50650[10WOo]: register single client
derp client 10.0.1.1:50650[10WOo]: received forwarded packet from [SbsJn] via [dM2E3]
derp client 10.0.1.1:50650[10WOo]: sendPkt attempt 0 enqueued
derp client 10.0.1.1:50650[10WOo]: sendPacket from [SbsJn]: <nil>
derp client 10.0.1.1:50650[10WOo]: read frame type 0 len 0 err EOF
derp client 10.0.1.1:50650[10WOo]: read EOF
derp client 10.0.1.1:50650[10WOo]: sender failed: context canceled
derp client 10.0.1.1:50650[10WOo]: removing connection
```

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Kyle Carberry 3862a1e1d5 derp/derphttp: cleanup WebSocket connection on close
This was causing a leak in our CI!

Signed-off-by: Kyle Carberry <kyle@carberry.com>
2 years ago
Mihai Parparita 6ac6ddbb47 sockstats: switch label to enum
Makes it cheaper/simpler to persist values, and encourages reuse of
labels as opposed to generating an arbitrary number.

Updates tailscale/corp#9230
Updates #3363

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita 9cb332f0e2 sockstats: instrument networking code paths
Uses the hooks added by tailscale/go#45 to instrument the reads and
writes on the major code paths that do network I/O in the client. The
convention is to use "<package>.<type>:<label>" as the annotation for
the responsible code path.

Enabled on iOS, macOS and Android only, since mobile platforms are the
ones we're most interested in, and we are less sensitive to any
throughput degradation due to the per-I/O callback overhead (macOS is
also enabled for ease of testing during development).

For now just exposed as counters on a /v0/sockstats PeerAPI endpoint.

We also keep track of the current interface so that we can break out
the stats by interface.

Updates tailscale/corp#9230
Updates #3363

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
David Anderson 8b2ae47c31 version: unexport all vars, turn Short/Long into funcs
The other formerly exported values aren't used outside the package,
so just unexport them.

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
Brad Fitzpatrick cf8dd7aa09 all: use Go 1.20's bytes.Clone
Updates #7123
Updates #6257 (more to do in other repos)

Change-Id: I073e2a6d81a5d7fbecc29caddb7e057ff65239d0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick b1248442c3 all: update to Go 1.20, use strings.CutPrefix/Suffix instead of our fork
Updates #7123
Updates #5309

Change-Id: I90bcd87a2fb85a91834a0dd4be6e03db08438672
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Maisem Ali 5bba65e978 net/memnet: rename from net/nettest
This is just #cleanup to resolve a TODO

Also add a package doc.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Will Norris 947c14793a all: update tools that manage copyright headers
Update all code generation tools, and those that check for license
headers to use the new standard header.

Also update copyright statement in LICENSE file.

Fixes #6865

Signed-off-by: Will Norris <will@tailscale.com>
2 years ago
Will Norris 71029cea2d all: update copyright and license headers
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>
2 years ago
Anton Tolchanov 6cc6c70d70 derp: prevent concurrent access to multiForwarder map
Instead of iterating over the map to determine the preferred forwarder
on every packet (which could happen concurrently with map mutations),
store it separately in an atomic variable.

Fixes #6445

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Mihai Parparita 33520920c3 all: use strs.CutPrefix and strs.CutSuffix more
Updates places where we use HasPrefix + TrimPrefix to use the combined
function.

Updates #5309

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Maisem Ali 1f4669a380 all: standardize on LocalAPI
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick da8def8e13 all: remove old +build tags
The //go:build syntax was introduced in Go 1.17:

https://go.dev/doc/go1.17#build-lines

gofmt has kept the +build and go:build lines in sync since
then, but enough time has passed. Time to remove them.

Done with:

    perl -i -npe 's,^// \+build.*\n,,' $(git grep -l -F '+build')

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick f4ff26f577 types/pad32: delete package
Use Go 1.19's new 64-bit alignment ~hidden feature instead.

Fixes #5356

Change-Id: Ifcbcb115875a7da01df3bc29e9e7feadce5bc956
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Mihai Parparita 9d04ffc782 net/wsconn: add back custom wrapper for turning a websocket.Conn into a net.Conn
We removed it in #4806 in favor of the built-in functionality from the
nhooyr.io/websocket package. However, it has an issue with deadlines
that has not been fixed yet (see nhooyr/websocket#350). Temporarily
go back to using a custom wrapper (using the fix from our fork) so that
derpers will stop closing connections too aggressively.

Updates #5921

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Andrew Dunham 64ea60aaa3
derp: add TCP RTT metric on Linux (#5949)
Periodically poll the TCP RTT metric from all open TCP connections and
update a (bucketed) histogram metric.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I6214902196b05bf7829c9d0ea501ce0e13d984cf
2 years ago
Mihai Parparita b2855cfd86 derp/derphttp: fix nil pointer dereference when closing a netcheck client
NewNetcheckClient only initializes a subset of fields of derphttp.Client,
and the Close() call added by #5707 was result in a nil pointer dereference.
Make Close() safe to call when using NewNetcheckClient() too.

Fixes #5919

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Josh Soref d4811f11a0 all: fix spelling mistakes
Signed-off-by: Josh Soref <2119212+jsoref@users.noreply.github.com>
2 years ago
Eng Zer Jun f0347e841f refactor: move from io/ioutil to io and os packages
The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.

Reference: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
2 years ago
Mihai Parparita 027111fb5a derp: update DERP acronym expansion
Makes the package description consistent with other documentation.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Brad Fitzpatrick 74674b110d envknob: support changing envknobs post-init
Updates #5114

Change-Id: Ia423fc7486e1b3f3180a26308278be0086fae49b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Maisem Ali a9f6cd41fd all: use syncs.AtomicValue
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick 4950fe60bd syncs, all: move to using Go's new atomic types instead of ours
Fixes #5185

Change-Id: I850dd532559af78c3895e2924f8237ccc328449d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 116f55ff66 all: gofmt for Go 1.19
Updates #5210

Change-Id: Ib02cd5e43d0a8db60c1f09755a8ac7b140b670be
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick a12aad6b47 all: convert more code to use net/netip directly
perl -i -npe 's,netaddr.IPPrefixFrom,netip.PrefixFrom,' $(git grep -l -F netaddr.)
    perl -i -npe 's,netaddr.IPPortFrom,netip.AddrPortFrom,' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPrefix,netip.Prefix,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPort,netip.AddrPort,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IP\b,netip.Addr,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPv6Raw\b,netip.AddrFrom16,g' $(git grep -l -F netaddr. )
    goimports -w .

Then delete some stuff from the net/netaddr shim package which is no
longer neeed.

Updates #5162

Change-Id: Ia7a86893fe21c7e3ee1ec823e8aba288d4566cd8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 6a396731eb all: use various net/netip parse funcs directly
Mechanical change with perl+goimports.

Changed {Must,}Parse{IP,IPPrefix,IPPort} to their netip variants, then
goimports -d .

Finally, removed the net/netaddr wrappers, to prevent future use.

Updates #5162

Change-Id: I59c0e38b5fbca5a935d701645789cddf3d7863ad
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 7eaf5e509f net/netaddr: start migrating to net/netip via new netaddr adapter package
Updates #5162

Change-Id: Id7bdec303b25471f69d542f8ce43805328d56c12
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Charlotte Brandhorst-Satzkorn 4c0feba38e
derp: plumb '/derp' request context through (#5083)
This change is required to implement tracing for derp.

Signed-off-by: Charlotte Brandhorst-Satzkorn <charlotte@tailscale.com>
2 years ago
Brad Fitzpatrick 931f18b575 derp: add missing docs on clientInfo.Version
It's not the Tailscale version.

Change-Id: Icfbd5ff36300b2125b19cd2fa6caa22876965317
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Mihai Parparita edc90ebc61 net/wsconn: remove homegrown wrapper for turning a websocket.Conn into a net.Conn
The one from the nhooyr/websocket package seems to work equally well.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita a9f32656f5 control/controlhttp: allow client and server to communicate over WebSockets
We can't do Noise-over-HTTP in Wasm/JS (because we don't have bidirectional
communication), but we should be able to do it over WebSockets. Reuses
derp WebSocket support that allows us to turn a WebSocket connection
into a net.Conn.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
James Tucker f9e86e64b7 *: use WireGuard where logged, printed or named
Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
Tom DNetto c8f4dfc8c0 derp/derphttp,net/netcheck: improve netcheck behavior under MITM proxies
In cases where tailscale is operating behind a MITM proxy, we need to consider
that a lot more of the internals of our HTTP requests are visible and may be
used as part of authorization checks. As such, we need to 'behave' as closely
as possible to ideal.

 - Some proxies do authorization or consistency checks based the on Host header
   or HTTP URI, instead of just the IP/hostname/SNI. As such, we need to
   construct a `*http.Request` with a valid URI everytime HTTP is going to be
   used on the wire, even if its over TLS.
   Aside from the singular instance in net/netcheck, I couldn't find anywhere
   else a http.Request was constructed incorrectly.

 - Some proxies may deny requests, typically by returning a 403 status code. We
   should not consider these requests as a valid latency check, so netcheck
   semantics have been updated to consider >299 status codes as a failed probe.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Maisem Ali 9f604f2bd3
derp: add (*Server).IsClientConnectedForTest func. (#4331)
This allows tests to verfiy that a DERP connection was actually
established.

Related to #4326
Updates tailscale/corp#2579

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick 18818763d1 derp: set Basic Constraints on metacert
See https://github.com/golang/go/issues/51759#issuecomment-1071147836

Once we deploy this, tailscaled should work again for macOS users with
Go 1.18.

Updates golang/go#51759

Change-Id: I869b6ddc556a2de885e96ccf9f335dfc8f6f6a7e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 0868329936 all: use any instead of interface{}
My favorite part of generics.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 730aa1c89c derp/derphttp, wgengine/magicsock: prefer IPv6 to DERPs when IPv6 works
Fixes #3838

Change-Id: Ie47a2a30c7e8e431512824798d2355006d72fb6a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 70d71ba1e7 cmd/derpprobe: check derper TLS certs too
Change-Id: If8c48e012b294570ebbb1a46bacdc58fafbfbcc5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 41fd4eab5c envknob: add new package for all the strconv.ParseBool(os.Getenv(..))
A new package can also later record/report which knobs are checked and
set. It also makes the code cleaner & easier to grep for env knobs.

Change-Id: Id8a123ab7539f1fadbd27e0cbeac79c2e4f09751
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2aeb93003f derp: add metrics to server got pings, sent pongs
Updates #3652

Change-Id: I1d350bcaee39ea36b0c71912028624d18fb541b4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2c94e3c4ad wgengine/magicsock: don't unconditionally close DERP connections on rebind
Only if the source address isn't on the currently active interface or
a ping of the DERP server fails.

Updates #3619

Change-Id: I6bf06503cff4d781f518b437c8744ac29577acc8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 63d9c7b9b3 derp: add Client.LocalAddr method
So magicsock can later ask a DERP connection whether its source IP
would've changed if it reconnected.

Updates #3619

Change-Id: Ibc8810340c511d6786b60c78c1a61c09f5800e40
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 535b925d1b derp/derphttp: add Client.Ping, SendPing methods
Continuing work in 434af15a04, to make it possible for magicsock to
probe whether a DERP server is still there.

Updates #3619

Change-Id: I366a77c27e93b876734e64f445b85ef01eb590f2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 434af15a04 derp: support client->server ping (and server->client pong)
In prep for a future change to have client ping derp connections
when their state is questionable, rather than aggressively tearing
them down and doing a heavy reconnect when their state is unknown.

We already support ping/pong in the other direction (servers probing
clients) so we already had the two frame types, but I'd never finished
this direction.

Updates #3619

Change-Id: I024b815d9db1bc57c20f82f80f95fb55fc9e2fcc
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 758c37b83d net/netns: thread logf into control functions
So that darwin can log there without panicking during tests.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
David Anderson 84c3a09a8d types/key: export constants for key size, not a method.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson c1d009b9e9 ipn/ipnstate: use key.NodePublic instead of the generic key.Public.
Updates #3206.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 1f06f77dcb derp: remove package shadowing of types/key.
Updates #3206

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 37c150aee1 derp: use new node key type.
Update #3206

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Brad Fitzpatrick eebe7afad7 derp/derphttp: only log about a weird upgrade if any was specified
Otherwise random browser requests to /derp cause log spam.

Change-Id: I7bdf991d2106f0323868e651156c788a877a90d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 505f844a43 cmd/derper, derp/derphttp: add websocket support
Updates #3157

Change-Id: I337a919a3b350bc7bd9af567b49c4d5d6616abdd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 7cf8ec8108 net/tlsdial: bake in LetsEncrypt's ISRG Root X1 root
We still try the host's x509 roots first, but if that fails (like if
the host is old), we fall back to using LetsEncrypt's root and
retrying with that.

tlsdial was used in the three main places: logs, control, DERP. But it
was missing in dnsfallback. So added it there too, so we can run fine
now on a machine with no DNS config and no root CAs configured.

Also, move SSLKEYLOGFILE support out of DERP. tlsdial is the logical place
for that support.

Fixes #1609

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 73f177e4d5 derp: throttle client sends if server advertises rate limits
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 3759fb8987 derp: deflake TestSendFreeze
On about 1 out of 500 runs, TestSendFreeze failed:

    derp_test.go:416: bob: unexpected message type derp.PeerGoneMessage

Closing alice before bob created a race.
If bob closed promptly, the test passed.
If bob closed slowly, and alice's disappearance caused
bob to receive a PeerGoneMessage before closing, the test failed.

Deflake the test by closing bob first.
With this fix, the test passed 12,000 times locally.

Fixes #2668

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick fc160f80ee metrics: move currentFDs code to the metrics package
Updates #2784

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick a59b389a6a derp: add new health update and server restarting frame types
Updates #2756
Updates #2746

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 73280595a8 derp: accept dup clients without closing prior's connection
A public key should only have max one connection to a given
DERP node (or really: one connection to a node in a region).

But if people clone their machine keys (e.g. clone their VM, Raspbery
Pi SD card, etc), then we can get into a situation where a public key
is connected multiple times.

Originally, the DERP server handled this by just kicking out a prior
connections whenever a new one came. But this led to reconnect fights
where 2+ nodes were in hard loops trying to reconnect and kicking out
their peer.

Then a909d37a59 tried to add rate
limiting to how often that dup-kicking can happen, but empirically it
just doesn't work and ~leaks a bunch of goroutines and TCP
connections, tying them up for hour+ while more and more accumulate
and waste memory. Mostly because we were doing a time.Sleep forever
while not reading from their TCP connections.

Instead, just accept multiple connections per public key but track
which is the most recent. And if two both are writing back & forth,
then optionally disable them both. That last part is only enabled in
tests for now. The current default policy is just last-sender-wins
while we gather the next round of stats.

Updates #2751

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick ffd22050c0 derp: export current file descriptor metric 3 years ago
slowy07 ac0353e982 fix: typo spelling grammar
Signed-off-by: slowy07 <slowy.arfy@gmail.com>
3 years ago
Brad Fitzpatrick f35b8c3ead derp: fix meshing accounting edge case bug
If a peer is connected to multiple nodes in a region (so
multiForwarder is in use) and then a node restarts and re-sends all
its additions, this bug about whether an element is in the
multiForwarder could cause a one-time flip in the which peer node we
forward to.  Note a huge deal, but not written as intended.

Thanks to @lewgun for the bug report in #2141.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick fd7b738e5b derp: use pad32 package for padding, reduce duplication
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 7298e777d4 derp: reduce server memory by 30% by removing persistent bufio.Writer
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick b622c60ed0 derp,wgengine/magicsock: don't assume stringer is in $PATH for go:generate
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e422e9f4c9 cmd/derper: mesh over VPC network
Updates #2414

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e299300b48 net/dnscache: cache all IPs per hostname
Not yet used in the dialer, but plumbed around.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick a909d37a59 derp: rate limit how often same-key clients can kick each other off server
Updates #392
Updates #506

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 4dbbd0aa4a cmd/addlicense: add command to add licenseheaders to generated code
And use it to make our stringer invocations match the existing code.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 0ec9040c5e scripts: remove special case for _strings.go files in check license headers
And add a license header for derp/dropreason_string.go to make it happy.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
maddie d976a84d7e derp: allow self node when verifying clients
Fixes #2408

Signed-off-by: Maddie Zhan <maddie.zhan@cynovan.com>
3 years ago
Brad Fitzpatrick 05da2691a5 cmd/derper/derpprobe: add derp prober
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 4c0494185b derp: remove "fine for now" intentional slow memory leak from derp server
It was once believed that it might be useful. It wasn't. We never used it.

Remove it so we don't slowly leak memory.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson d98829583a derp: use a dedicated queue for disco traffic.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 67158549ab derp: actually export the new drop counter.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 36492ace9d derp: add counters to track the type of dropped packets.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Brad Fitzpatrick 7e7c4c1bbe tailcfg: break DERPNode.DERPTestPort into DERPPort & InsecureForTests
The DERPTestPort int meant two things before: which port to use, and
whether to disable TLS verification. Users would like to set the port
without disabling TLS, so break it into two options.

Updates #1264

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
julianknodt 506c2fe8e2 cmd/tailscale: make netcheck use active DERP map, delete static copy
After allowing for custom DERP maps, it's convenient to be able to see their latency in
netcheck. This adds a query to the local tailscaled for the current DERPMap.

Updates #1264

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 148602a89a derp,cmd/derper: allow server to verify clients
This adds a flag to the DERP server which specifies to verify clients through a local
tailscaled. It is opt-in, so should not affect existing clients, and is mainly intended for
users who want to run their own DERP servers. It assumes there is a local tailscaled running and
will attempt to hit it for peer status information.

Updates #1264

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 3687e5352b derp: fix traffic handler peer addresses
Before it was using the local address and port, so fix that.
The fields in the response from `ss` are:

State, Recv-Q, Send-Q, Local Address:Port, Peer Address:Port, Process

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 3728634af9 derp: add debug traffic handler
This adds a handler on the DERP server for logging bytes send and received by clients of the
server, by holding open a connection and recording if there is a difference between the number
of bytes sent and received. It sends a JSON marshalled object if there is an increase in the
number of bytes.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt fe54721e31 derp: add pkt queue latency timer
It would be useful to know the time that packets spend inside of a queue before they are sent
off, as that can be indicative of the load the server is handling (and there was also an
existing TODO). This adds a simple exponential moving average metric to track the average packet
queue duration.
Changes during review:
Add CAS loop for recording queue timing w/ expvar.Func, rm snake_case, annotate in milliseconds,
convert

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Brad Fitzpatrick 3d4d97601a derp/derpmap: add São Paulo (derp11)
Updates #1499
4 years ago
Maisem Ali 4d142ebe06 derp: handle net.ErrClosed in TestSendFreeze
Signed-off-by: Maisem Ali <maisem@tailscale.com>
4 years ago
Brad Fitzpatrick ab2a8a7493 derp: return keep-alive message up to callers
To be used by health checking, which wants to see activity, even if idle.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick c81814e4f8 derp{,/derphttp},magicsock: tell DERP server when ping acks can be expected
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 79d8288f0a wgengine/magicsock, derp, derp/derphttp: respond to DERP server->client pings
No server support yet, but we want Tailscale 1.6 clients to be able to respond
to them when the server can do it.

Updates #1310

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick ca51529b81 derp/derphttp: return nicer errors from Recv on Close 4 years ago
Brad Fitzpatrick 741d654aa3 derp/derphttp: add a context and infoLogger option to RunWatchConnectionLoop 4 years ago
Brad Fitzpatrick 66be052a70 net/dnscache: work on IPv6-only hosts (again)
This fixes the regression where we had stopped working on IPv6-only
hosts.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
David Anderson 54e6c3a290 version: use OSS repo's version when building.
When building with redo, also include the git commit hash
from the proprietary repo, so that we have a precise commit
that identifies all build info (including Go toolchain version).

Add a top-level build script demonstrating to downstream distros
how to burn the right information into builds.

Adjust `tailscale version` to print commit hashes when available.

Fixes #841.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick 1e0be5a458 tshttp, derphttp: send Proxy-Authorization, not Authorization, to proxies
Whoops. But weirdly, sending Authorization sometimes worked?
4 years ago
Brad Fitzpatrick 28f9cd06f5 tshttpproxy, controlclient, derphttp, logpolicy: send Negotiate auth to proxies
For Windows only, and only when built with Tailscale's Go tree.

Updates tailscale/corp#583
4 years ago
Brad Fitzpatrick 169ff22a84 derp: set NotBefore and NotAfter in DERP server's metacert
Fixes regression from e415991256 that
only affected Windows users because Go only on Windows delegates x509
cert validation to the OS and Windows as unhappy with our "metacert"
lacking NotBefore and NotAfter.

Fixes #705
4 years ago