Commit Graph

449 Commits (a34350ffda1ae20b1b988a55a55ca3f995b54950)

Author SHA1 Message Date
David Anderson b3b1c06b3a net/dns: only restart systemd-resolved if we changed /etc/resolv.conf.
Reported on IRC: in an edge case, you can end up with a directManager DNS
manager and --accept-dns=false, in which case we should do nothing, but
actually end up restarting resolved whenever the netmap changes, even though
the user told us to not manage DNS.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 10547d989d net/dns: exhaustively test DNS selection paths for linux.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson c071bcda33 net/dns: relax systemd-resolved detection.
Reported on IRC: a resolv.conf that contained two entries for
"nameserver 127.0.0.53", which defeated our "is resolved actually
in charge" check. Relax that check to allow any number of nameservers,
as long as they're all 127.0.0.53.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 39748e9562 net/dns/resolver: authoritatively return NXDOMAIN for reverse zones we own.
Fixes #2774

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Emmanuel T Odeke 0daa32943e all: add (*testing.B).ReportAllocs() to every benchmark
This ensures that we can properly track and catch allocation
slippages that could otherwise have been missed.

Fixes #2748
3 years ago
Brad Fitzpatrick 065c4ffc2c net/dns: add start of Linux newOSConfigurator tests
Only one test case so far.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 09a47ea3f1 net/dns: prep for writing manager_linux tests; pull some stuff out
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3606e68721 net/interfaces: fix default route lookup on Windows
It wasn't using the right metric. Apparently you're supposed to sum the route
metric and interface metric. Whoops.

While here, optimize a few little things too, not that this code
should be too hot.

Fixes #2707 (at least; probably dups but I'm failing to find)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson b49d9bc74d net/portmapper: fix "running a test" condition.
Fixes #2686.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
slowy07 ac0353e982 fix: typo spelling grammar
Signed-off-by: slowy07 <slowy.arfy@gmail.com>
3 years ago
David Crawshaw 0ac2130590 net/dns: resolveConfExists reading the wrong error
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Brad Fitzpatrick 36ffd509de net/dns: avoid Linux PolicyKit GUI dialog during tests
Fixes #2672

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Maisem Ali 1f006025c2 net/tstun: fix build on arm
Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick cd426eaf4c net/portmapper: fix t.Log-after-test-done race in tests
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Matt Layher 8ab44b339e net/tstun: use unix.Ifreq type for Linux TAP interface configuration
Signed-off-by: Matt Layher <mdlayher@gmail.com>
3 years ago
Josh Bleecher Snyder a24cee0d67 all: simplify ts_macext build tags
Now that we have the easier-to-parse go:build build tags,
it is straightforward to simplify them. Yay.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 833200da6f net/tstun: don't exec uname -r on Linux in TUN failure diagnostics
Fixes https://twitter.com/zekjur/status/1425557520513486848

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e804ab29fd net/tstun: move TUN failure diagnostics to OS-specific files
Mostly so the Linux one can use Linux-specific stuff in package
syscall and not use os/exec for uname for portability.

But also it helps deps a tiny bit on iOS.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
julianknodt b9bd7dbc5d net/portmapper: log upnp information
This logs some basic statistics for UPnP, so that tailscale can better understand what routers
are being used and how to connect to them.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 26b6fe7f02 net/portmapper: add PCP integration test
This adds a PCP test to the IGD test server, by hardcoding in a few observed packets from
Denton's box.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Brad Fitzpatrick bdb93c5942 net/portmapper: actually test something in TestProbeIntegration
And use dynamic port numbers in tests, as Linux on GitHub Actions and
Windows in general have things running on these ports.

Co-Author: Julian Knodt <julianknodt@gmail.com>
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Adrian Dewhurst 8bdf878832 net/dns/resolver: use forwarded dns txid directly
Previously, we hashed the question and combined it with the original
txid which was useful when concurrent queries were multiplexed on a
single local source port. We encountered some situations where the DNS
server canonicalizes the question in the response (uppercase converted
to lowercase in this case), which resulted in responses that we couldn't
match to the original request due to hash mismatches. This includes a
new test to cover that situation.

Fixes #2597

Signed-off-by: Adrian Dewhurst <adrian@tailscale.com>
3 years ago
Brad Fitzpatrick e6d4ab2dd6 net/portmapper: add start of self-contained portmapper integration tests
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
julianknodt 98d36ee18d net/portmapper: add hook for use with prev ip
PCP handles external IPs by allowing the client to specify them in the packet, which is more
explicit than requiring 2 packets from PMP, so allow for future changes to add it in easily.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 85304d7392 net/portmapper: check disable flags
Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 777b711d96 net/portmapper: add pcp portmapping
This adds PCP portmapping, hooking into the existing PMP portmapping.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
julianknodt 5c98b1b8d0 net/portmapper: move pcp code to separate file
This moves all the PCP code to a separate file in preparation for portmapping with PCP.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Josh Bleecher Snyder a5da4ed981 all: gofmt with Go 1.17
This adds "//go:build" lines and tidies up existing "// +build" lines.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick a729070252 net/tstun: add start of Linux TAP support, with DHCP+ARP server
Still very much a prototype (hard-coded IPs, etc) but should be
non-invasive enough to submit at this point and iterate from here.

Updates #2589

Co-Author: David Crawshaw <crawshaw@tailscale.com>
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick fdc081c291 net/portmapper: fix UPnP probing, work against all ports
Prior to Tailscale 1.12 it detected UPnP on any port.
Starting with Tailscale 1.11.x, it stopped detecting UPnP on all ports.

Then start plumbing its discovered Location header port number to the
code that was assuming port 5000.

Fixes #2109

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Denton Gentry 260b85458c net/dns: correct log message.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Brad Fitzpatrick 54e33b511a net/dns/resolver: add test that I forgot to git add earlier
This was meant to be part of 53a2f63658 earlier
but I guess I failed at git.

Updates #2436
Updates tailscale/corp#2250
Updates tailscale/corp#2238

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick be921d1a95 net/dns/resolver: fix skipped DoH test that bitrot
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 5a7ff2b231 net/dnsfallback: re-run go generate 3 years ago
Matt Layher effee49e45 net/interfaces: explicitly check netaddr.IP.Is6 in isUsableV6
Signed-off-by: Matt Layher <mdlayher@gmail.com>
3 years ago
Matt Layher 3ff8a55fa7 net/tsaddr: remove IsULA, replace with netaddr.IP.IsPrivate
Signed-off-by: Matt Layher <mdlayher@gmail.com>
3 years ago
Josh Bleecher Snyder c2202cc27c net/tstun: use mono.Time
There's a call to Now once per packet.
Move to mono.Now.

Though the current implementation provides high precision,
we document it to be coarse, to preserve the ability
to switch to a coarse monotonic time later.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 881bb8bcdc net/dns/resolver: allow an extra alloc for go closure allocation
Go 1.17 switches to a register ABI on amd64 platforms.
Part of that switch is that go and defer calls use an argument-less
closure, which allocates. This means that we have an extra
alloc in some DNS work. That's unfortunate but not a showstopper,
and I don't see a clear path to fixing it.
The other performance benefits from the register ABI will all
but certainly outweigh this extra alloc.

Fixes #2545

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick b6179b9e83 net/dnsfallback: add new nodes
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Crawshaw f414a9cc01 net/dns/resolver: EDNS OPT record off-by-one
I don't know how to get access to a real packet. Basing this commit
entirely off:

       +------------+--------------+------------------------------+
       | Field Name | Field Type   | Description                  |
       +------------+--------------+------------------------------+
       | NAME       | domain name  | MUST be 0 (root domain)      |
       | TYPE       | u_int16_t    | OPT (41)                     |
       | CLASS      | u_int16_t    | requestor's UDP payload size |
       | TTL        | u_int32_t    | extended RCODE and flags     |
       | RDLEN      | u_int16_t    | length of all RDATA          |
       | RDATA      | octet stream | {attribute,value} pairs      |
       +------------+--------------+------------------------------+

From https://datatracker.ietf.org/doc/html/rfc6891#section-6.1.2

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Josh Bleecher Snyder 1034b17bc7 net/tstun: buffer outbound channel
The handoff between tstun.Wrap's Read and poll methods
is one of the per-packet hotspots. It shows up in pprof.

Making outbound buffered increases throughput.

It is hard to measure exactly how much, because the numbers
are highly variable, but I'd estimate it at about 1%,
using the best observed max throughput across three runs.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 965dccd4fc net/tstun: buffer outbound channel
The handoff between tstun.Wrap's Read and poll methods
is one of the per-packet hotspots. It shows up in pprof.

Making outbound buffered increases throughput.

It is hard to measure exactly how much, because the numbers
are highly variable, but I'd estimate it at about 1%,
using the best observed max throughput across three runs.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 68df379a7d net/portmapper: rename ErrGatewayNotFound to ErrGatewayRange, reword text
It confused & scared people. And it was just bad.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick aaf2df7ab1 net/{dnscache,interfaces}: use netaddr.IP.IsPrivate, delete copied code
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c17d743886 net/dnscache: update a comment
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 281d503626 net/dnscache: make Dialer try all resolved IPs
Tested manually with:

$ go test -v ./net/dnscache/ -dial-test=bogusplane.dev.tailscale.com:80

Where bogusplane has three A records, only one of which works.

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 53a2f63658 net/dns/resolver: race well-known resolvers less aggressively
Instead of blasting away at all upstream resolvers at the same time,
make a timing plan upon reconfiguration and have each upstream have an
associated start delay, depending on the overall forwarding config.

So now if you have two or four upstream Google or Cloudflare DNS
servers (e.g. two IPv4 and two IPv6), we now usually only send a
query, not four.

This is especially nice on iOS where we start fewer DoH queries and
thus fewer HTTP/1 requests (because we still disable HTTP/2 on iOS),
fewer sockets, fewer goroutines, and fewer associated HTTP buffers,
etc, saving overall memory burstiness.

Fixes #2436
Updates tailscale/corp#2250
Updates tailscale/corp#2238

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e94ec448a7 net/dns/resolver: add forwardQuery type as race work prep
Add a place to hang state in a future change for #2436.
For now this just simplifies the send signature without
any functional change.

Updates #2436

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 064b916b1a net/dns/resolver: fix func used as netaddr.IP in printf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 7b295f3d21 net/portmapper: disable UPnP on iOS for now
Updates #2495

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick cecfc14875 net/dns: don't build init*.go on non-windows
To remove the regexp dep on iOS, notably.

Updates tailscale/corp#2238

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2968893add net/dns/resolver: bound DoH usage on iOS
Updates tailscale/corp#2238

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3daf27eaad net/dns/resolver: fall back to IPv6 for well-known DoH servers if v4 fails
Should help with IPv6-only environments when the tailnet admin
only specified IPv4 DNS IPs.

See https://github.com/tailscale/tailscale/issues/2447#issuecomment-884188562

Co-Author: Adrian Dewhurst <adrian@tailscale.com>
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 74eee4de1c net/dns/resolver: use correct Cloudflare DoH hostnames
We were using the wrong ones for the malware & adult content
variants. Docs:

https://developers.cloudflare.com/1.1.1.1/1.1.1.1-for-families/setup-instructions/dns-over-https

Earlier commit which added them:
236eb4d04d

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
julianknodt 3a4201e773 net/portmapper: return correct upnp port
Previously, this was incorrectly returning the internal port, and using that with the external
exposed IP when it did not use WANIPConnection2. In the case when we must provide a port, we
return it instead.

Noticed this while implementing the integration test for upnp.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Brad Fitzpatrick e74d37d30f net/dns{,/resolver}: quiet DNS output logging
It was a huge chunk of the overall log output and made debugging
difficult. Omit and summarize the spammy *.arpa parts instead.

Fixes tailscale/corp#2066 (to which nobody had opinions, so)
3 years ago
Josh Bleecher Snyder 84a6dcd9a9 net/dnsfallback: regenerate
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 171ec9f8f4 control/{controlknobs,controlclient}: simplify knobs API, fix controlclient crash
From integration tests elsewhere:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x70 pc=0x845c9b]

goroutine 226 [running]:
tailscale.com/control/controlclient.(*Direct).sendMapRequest(0xc00053e1e0, 0x16670f0, 0xc000353780, 0xffffffffffffffff, 0xc0003e5f10, 0x0, 0x0)
   /home/runner/go/pkg/mod/tailscale.com@v1.1.1-0.20210715222212-1bb6abc604c1/control/controlclient/direct.go:803 +0x19bb
tailscale.com/control/controlclient.(*Direct).PollNetMap(...)
   /home/runner/go/pkg/mod/tailscale.com@v1.1.1-0.20210715222212-1bb6abc604c1/control/controlclient/direct.go:574
tailscale.com/control/controlclient.(*Auto).mapRoutine(0xc00052a1e0)
   /home/runner/go/pkg/mod/tailscale.com@v1.1.1-0.20210715222212-1bb6abc604c1/control/controlclient/auto.go:464 +0x571
created by tailscale.com/control/controlclient.(*Auto).Start
   /home/runner/go/pkg/mod/tailscale.com@v1.1.1-0.20210715222212-1bb6abc604c1/control/controlclient/auto.go:151 +0x65
exit status 2

Also remove types/opt.Bool API addition which is now unnecessary.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
julianknodt 1bb6abc604 net/portmapper: add upnp port mapping
Add in UPnP portmapping, using goupnp library in order to get the UPnP client and run the
portmapping functions. This rips out anywhere where UPnP used to be in portmapping, and has a
flow separate from PMP and PCP.

RELNOTE=portmapper now supports UPnP mappings

Fixes #682
Updates #2109

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Brad Fitzpatrick 236eb4d04d net/dns/resolver: upgrade forwarded MagicDNS queries to DoH when IP known
Recognize Cloudflare, Google, Quad9 which are by far the
majority of upstream DNS servers that people use.

RELNOTE=MagicDNS now uses DNS-over-HTTPS when querying popular upstream resolvers,
so DNS queries aren't sent in the clear over the Internet.

Updates #915 (might fix it?)
Updates #988 (gets us closer, if it fixes Android)
Updates #74 (not yet configurable, but progress)
Updates #2056 (not yet configurable, dup of #74?)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaditya Chaudhary 4f89fe17a2
Implemented Commandline Download Speedtest (#2064)
Added the net/speedtest package that contains code for starting up a
speedtest server and a client. The speedtest command for starting a
client takes in a duration for the speedtest as well as the host and
port of the speedtest server to connect to. The speedtest command for
starting a server takes in a host:port pair to listen on.

Signed-off-by: Aaditya Chaudhary <32117362+AadityaChaudhary@users.noreply.github.com>
3 years ago
Denton Gentry e28bc49e5f netns_linux: remove special handling for tests.
With netns handling localhost now, existing tests no longer
need special handling. The tests set up their connections to
localhost, and the connections work without fuss.

Remove the special handling for tests.

Also remove the hostinfo.TestCase support, since this was
the only use of it. It can be added back later if really
needed, but it would be better to try to make tests work
without special cases.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Denton Gentry d2480fd508 net/netns: support !CAP_NET_ADMIN
netns_linux checked whether "ip rule" could run to determine
whether to use SO_MARK for network namespacing. However in
Linux environments which lack CAP_NET_ADMIN, such as various
container runtimes, the "ip rule" command succeeds but SO_MARK
fails due to lack of permission. SO_BINDTODEVICE would work in
these environments, but isn't tried.

In addition to running "ip rule" check directly whether SO_MARK
works or not. Among others, this allows Microsoft Azure App
Service and AWS App Runner to work.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Denton Gentry 1896bf99d9 netns_linux: No namespace for localhost.
Connections to a control server or log server on localhost,
used in a number of tests, are working right now because the
calls to SO_MARK in netns fail for non-root but then we ignore
the failure when running in tests.

Unfortunately that failure in SO_MARK also affects container
environments without CAP_NET_ADMIN, breaking Tailscale
connectivity. We're about to fix netns to recognize when SO_MARK
doesn't work and use SO_BINDTODEVICE instead. Doing so makes
tests fail, as their sockets now BINDTODEVICE of the default
route and cannot connect to localhost.

Add support to skip namespacing for localhost connections,
which Darwin and Windows already do. This is not conditional
on running within a test, if you tell tailscaled to connect
to localhost it will automatically use a non-namespaced
socket to do so.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Denton Gentry 61622b18fa net/interface: add AWS App Runner /proc/net/route test
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Brad Fitzpatrick 92077ae78c wgengine/magicsock: make portmapping async
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 440566c5d2 net/interfaces: trim getPACWindows whitespace before parsing URL
Fixes #2357

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 0ad92b89a6 net/tstun: fix data races
To remove some multi-case selects, we intentionally allowed
sends on closed channels (cc23049cd2).

However, we also introduced concurrent sends and closes,
which is a data race.

This commit fixes the data race. The mutexes here are uncontended,
and thus very cheap.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder c35a832de6 net/tstun: add inner loop to poll
This avoids re-enqueuing to t.bufferConsumed,
which makes the code a bit clearer.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder a4cc7b6d54 net/tstun: simplify code
Calculate whether the packet is injected directly,
rather than via an else branch.

Unify the exit paths. It is easier here than duplicating them.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder cc23049cd2 net/tstun: remove multi-case selects from hot code
Every TUN Read went through several multi-case selects.
We know from past experience with wireguard-go that these are slow
and cause scheduler churn.

The selects served two purposes: they separated errors from data and
gracefully handled shutdown. The first is fairly easy to replace by sending
errors and data over a single channel. The second, less so.

We considered a few approaches: Intricate webs of channels,
global condition variables. They all get ugly fast.

Instead, let's embrace the ugly and handle shutdown ungracefully.
It's horrible, but the horror is simple and localized.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
David Crawshaw 6b9f8208f4 net/dns: do not run wsl.exe as LocalSystem
It doesn't work. It needs to run as the user.

	https://github.com/microsoft/WSL/issues/4803

The mechanism for doing this was extracted from:

	https://web.archive.org/web/20101009012531/http://blogs.msdn.com/b/winsdk/archive/2009/07/14/launching-an-interactive-process-from-windows-service-in-windows-vista-and-later.aspx

While here, we also reclaculate WSL distro set on SetDNS.
This accounts for:

	1. potential inability to access wsl.exe on startup
	2. WSL being installed while Tailscale is running
	3. A new WSL distrobution being installed

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
David Crawshaw 1147c7fd4f net/dns: set WSL /etc/resolv.conf
We also have to make a one-off change to /etc/wsl.conf to stop every
invocation of wsl.exe clobbering the /etc/resolv.conf. This appears to
be a safe change to make permanently, as even though the resolv.conf is
constantly clobbered, it is always the same stable internal IP that is
set as a nameserver. (I believe the resolv.conf clobbering predates the
MS stub resolver.)

Tested on WSL2, should work for WSL1 too.

Fixes #775

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
David Crawshaw 9b063b86c3 net/dns: factor directManager out over an FS interface
This is preliminary work for using the directManager as
part of a wslManager on windows, where in addition to configuring
windows we'll use wsl.exe to edit the linux file system and modify the
system resolv.conf.

The pinholeFS is a little funky, but it's designed to work through
simple unix tools via wsl.exe without invoking bash. I would not have
thought it would stand on its own like this, but it turns out it's
useful for writing a test for the directManager.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Brad Fitzpatrick 15677d8a0e net/socks5/tssocks: add a SOCKS5 dialer type, method-ifying code
https://twitter.com/bradfitz/status/1409605220376580097

Prep for #1970, #2264, #2268

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3910c1edaf net/socks5/tssocks: add new package, move SOCKS5 glue out of tailscaled
Prep for #1970, #2264, #2268

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Crawshaw d6f4b5f5cb ipn, etc: use controlplane.tailscale.com
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
julianknodt 72a0b5f042 net/dns/resolver: fmt item
This has been bothering me for a while, but everytime I run format from the root directory
it also formats this file. I didn't want to add it to my other PRs but it's annoying to have to
revert it every time.

Signed-off-by: julianknodt <julianknodt@gmail.com>
3 years ago
Brad Fitzpatrick 10d7c2583c net/dnsfallback: don't depend on derpmap.Prod
Move derpmap.Prod to a static JSON file (go:generate'd) instead,
to make its role explicit. And add a TODO about making dnsfallback
use an update-over-time DERP map file instead of a baked-in one.

Updates #1264

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Crawshaw 80b1308974 net/dns: remove ref to managerImpl
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Adrian Dewhurst bcaae3e074 net/dns/resolver: clamp EDNS size
This change (subject to some limitations) looks for the EDNS OPT record
in queries and responses, clamping the size field to fit within our DNS
receive buffer. If the size field is smaller than the DNS receive buffer
then it is left unchanged.

I think we will eventually need to transition to fully processing the
DNS queries to handle all situations, but this should cover the most
common case.

Mostly fixes #2066

Signed-off-by: Adrian Dewhurst <adrian@tailscale.com>
3 years ago
Brad Fitzpatrick 7b8ed1fc09 net/netns: add Android implementation, allowing registration of JNI hook
Updates #2102
Updates #1809

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3d777c13b0 net/socks5: fix a typo
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson 084d48d22d net/dns: always proxy through quad-100 on windows 8.1.
Windows 8.1 incorrectly handles search paths on an interface with no
associated resolver, so we have to provide a full primary DNS config
rather than use Windows 8.1's nascent-but-present NRPT functionality.

Fixes #2237.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Brad Fitzpatrick 45e64f2e1a net/dns{,/resolver}: refactor DNS forwarder, send out of right link on macOS/iOS
Fixes #2224
Fixes tailscale/corp#2045

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 733d52827b net/dns/resolver: skip test on macOS
Fixes #2229

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Denton Gentry ad288baaea net/interfaces: use IPv4 link local if nothing better
The only connectivity an AWS Lambda container has is an IPv4 link-local
169.254.x.x address using NAT:
12: vtarget_1@if11: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500
                    qdisc noqueue state UP group default qlen 1000
     link/ether 7e:1c:3f:00:00:00 brd ff:ff:ff:ff:ff:ff link-netnsid 1
     inet 169.254.79.1/32 scope global vtarget_1
     valid_lft forever preferred_lft forever

If there are no other IPv4/v6 addresses available, and we are running
in AWS Lambda, allow IPv4 169.254.x.x addresses to be used.

----

Similarly, a Google Cloud Run container's only connectivity is
a Unique Local Address fddf:3978:feb1:d745::c001/128.
If there are no other addresses available then allow IPv6
Unique Local Addresses to be used.
We actually did this in an earlier release, but now refactor it to
work the same way as the IPv4 link-local support is being done.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
David Crawshaw 297b3d6fa4 staticcheck.conf: turn off noisy lint errors
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Brad Fitzpatrick 1ae35b6c59 net/{interfaces,netcheck}: rename some fields, funcs
Split out of Denton's #2164, to make that diff smaller to review.

This change has no behavior changes.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson 9337826011 net/dns: fix inverted test for NetworkManager version.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 320cc8fa21 net/dns: verify that systemd-resolved is actually in charge.
It's possible to install a configuration that passes our current checks
for systemd-resolved, without actually pointing to systemd-resolved. In
that case, we end up programming DNS in resolved, but that config never
applies to any name resolution requests on the system.

This is quite a far-out edge case, but there's a simple additional check
we can do: if the header comment names systemd-resolved, there should be
a single nameserver in resolv.conf pointing to 127.0.0.53. If not, the
configuration should be treated as an unmanaged resolv.conf.

Fixes #2136.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson e7164425b3 net/dns: don't use NetworkManager for DNS on very old NetworkManagers.
Fixes #1945.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Dave Anderson 144c68b80b
net/dns: avoid using NetworkManager as much as possible. (#1945)
Addresses #1699 as best as possible.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Adrian Dewhurst 8b11937eaf net/dns/resolver: permit larger max responses, signal truncation
This raises the maximum DNS response message size from 512 to 4095. This
should be large enough for almost all situations that do not need TCP.
We still do not recognize EDNS, so we will still forward requests that
claim support for a larger response size than 4095 (that will be solved
later). For now, when a response comes back that is too large to fit in
our receive buffer, we now set the truncation flag in the DNS header,
which is an improvement from before but will prompt attempts to use TCP
which isn't supported yet.

On Windows, WSARecvFrom into a buffer that's too small returns an error
in addition to the data. On other OSes, the extra data is silently
discarded. In this case, we prefer the latter so need to catch the error
on Windows.

Partially addresses #1123

Signed-off-by: Adrian Dewhurst <adrian@tailscale.com>
4 years ago
David Anderson 7fab244614 net/dns/resolver: don't spam logs on EHOSTUNREACH.
Fixes #1719.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson df8a5d09c3 net/tstun: add a debug envvar to override tun MTU.
Signed-off-by: David Anderson <dave@natulte.net>
4 years ago
Brad Fitzpatrick 713c5c9ab1 net/{interfaces,netns}: change which build tag means mac/ios Network/System Extension
We used to use "redo" for that, but it was pretty vague.

Also, fix the build tags broken in interfaces_default_route_test.go from
a9745a0b68, moving those Linux-specific
tests to interfaces_linux_test.go.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick a321c24667 go.mod: update netaddr
Involves minor IPSetBuilder.Set API change.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick ca455ac84b net/tsaddr: simplify TailscaleServiceIP
netaddr allocated at the time this was written. No longer.

name                    old time/op  new time/op  delta
TailscaleServiceAddr-4  5.46ns ± 4%  1.83ns ± 3%  -66.52%  (p=0.008 n=5+5)

A bunch of the others can probably be simplified too, but this
was the only one with just an IP and not an IPPrefix.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago