Commit Graph

419 Commits (df7899759d3a23cbde4a66cdbd158facbecccf7f)

Author SHA1 Message Date
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>
3 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>
3 years ago
David Anderson 7fab244614 net/dns/resolver: don't spam logs on EHOSTUNREACH.
Fixes #1719.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 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
Josh Bleecher Snyder 1ece91cede go.mod: upgrade wireguard-windows, de-fork wireguard-go
Pull in the latest version of wireguard-windows.

Switch to upstream wireguard-go.
This requires reverting all of our import paths.

Unfortunately, this has to happen at the same time.
The wireguard-go change is very low risk,
as that commit matches our fork almost exactly.
(The only changes are import paths, CI files, and a go.mod entry.)
So if there are issues as a result of this commit,
the first place to look is wireguard-windows changes.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 5666663370 net/packet: use netaddr AppendTo methods
This lets us remote the types/strbuilder package,
which had only a single user.
And it's faster.

name              old time/op    new time/op    delta
String/tcp4-8        175ns ± 0%      58ns ± 1%  -66.95%  (p=0.000 n=10+9)
String/tcp6-8        226ns ± 1%     136ns ± 1%  -39.85%  (p=0.000 n=10+10)
String/udp4-8        175ns ± 1%      58ns ± 1%  -67.01%  (p=0.000 n=10+9)
String/udp6-8        230ns ± 1%     140ns ± 0%  -39.32%  (p=0.000 n=10+9)
String/icmp4-8       164ns ± 0%      50ns ± 1%  -69.89%  (p=0.000 n=10+10)
String/icmp6-8       217ns ± 1%     129ns ± 0%  -40.46%  (p=0.000 n=10+10)
String/igmp-8        196ns ± 0%      56ns ± 1%  -71.32%  (p=0.000 n=10+10)
String/unknown-8    2.06ns ± 1%    2.06ns ± 2%     ~     (p=0.985 n=10+10)

name              old alloc/op   new alloc/op   delta
String/tcp4-8        32.0B ± 0%     32.0B ± 0%     ~     (all equal)
String/tcp6-8         168B ± 0%       96B ± 0%  -42.86%  (p=0.000 n=10+10)
String/udp4-8        32.0B ± 0%     32.0B ± 0%     ~     (all equal)
String/udp6-8         168B ± 0%       96B ± 0%  -42.86%  (p=0.000 n=10+10)
String/icmp4-8       32.0B ± 0%     32.0B ± 0%     ~     (all equal)
String/icmp6-8        104B ± 0%       64B ± 0%  -38.46%  (p=0.000 n=10+10)
String/igmp-8        48.0B ± 0%     48.0B ± 0%     ~     (all equal)
String/unknown-8     0.00B          0.00B          ~     (all equal)

name              old allocs/op  new allocs/op  delta
String/tcp4-8         1.00 ± 0%      1.00 ± 0%     ~     (all equal)
String/tcp6-8         3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
String/udp4-8         1.00 ± 0%      1.00 ± 0%     ~     (all equal)
String/udp6-8         3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
String/icmp4-8        1.00 ± 0%      1.00 ± 0%     ~     (all equal)
String/icmp6-8        3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
String/igmp-8         1.00 ± 0%      1.00 ± 0%     ~     (all equal)
String/unknown-8      0.00           0.00          ~     (all equal)

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder d6d1951897 net/packet: add BenchmarkString
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
David Anderson e2dcf63420 net/dns: replace AuthoritativeSuffixes with nil Route entries.
This leads to a cleaner separation of intent vs. implementation
(Routes is now the only place specifying who handles DNS requests),
and allows for cleaner expression of a configuration that creates
MagicDNS records without serving them to the OS.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 6690f86ef4 net/dns: always offer MagicDNS records at 100.100.100.100.
Fixes #1886.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Josh Bleecher Snyder 25df067dd0 all: adapt to opaque netaddr types
This commit is a mishmash of automated edits using gofmt:

gofmt -r 'netaddr.IPPort{IP: a, Port: b} -> netaddr.IPPortFrom(a, b)' -w .
gofmt -r 'netaddr.IPPrefix{IP: a, Port: b} -> netaddr.IPPrefixFrom(a, b)' -w .

gofmt -r 'a.IP.Is4 -> a.IP().Is4' -w .
gofmt -r 'a.IP.As16 -> a.IP().As16' -w .
gofmt -r 'a.IP.Is6 -> a.IP().Is6' -w .
gofmt -r 'a.IP.As4 -> a.IP().As4' -w .
gofmt -r 'a.IP.String -> a.IP().String' -w .

And regexps:

\w*(.*)\.Port = (.*)  ->  $1 = $1.WithPort($2)
\w*(.*)\.IP = (.*)  ->  $1 = $1.WithIP($2)

And lots of manual fixups.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
David Anderson cfde997699 net/dns: don't use interfaces.Tailscale to find the tailscale interface index.
interfaces.Tailscale only returns an interface if it has at least one Tailscale
IP assigned to it. In the resolved DNS manager, when we're called upon to tear
down DNS config, the interface no longer has IPs.

Instead, look up the interface index on construction and reuse it throughout
the daemon lifecycle.

Fixes #1892.

Signed-off-by: David Anderson <dave@natulte.net>
4 years ago
Brad Fitzpatrick 3173c5a65c net/interface: remove darwin fetchRoutingTable workaround
Fixed upstream. Bump dep.

Updates #1345

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
David Anderson 3c8e230ee1 Revert "net/dns: set IPv4 auto mode in NM, so it lets us set DNS."
This reverts commit 7d16c8228b.

I have no idea how I ended up here. The bug I was fixing with this change
fails to reproduce on Ubuntu 18.04 now, and this change definitely does
break 20.04, 20.10, and Debian Buster. So, until we can reliably reproduce
the problem this was meant to fix, reverting.

Part of #1875

Signed-off-by: David Anderson <dave@natulte.net>
4 years ago
David Anderson 5bd38b10b4 net/dns: log the correct error when NM Reapply fails.
Found while debugging #1870.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 7d16c8228b net/dns: set IPv4 auto mode in NM, so it lets us set DNS.
Part of #1870.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 77e2375501 net/dns: don't try to configure LLMNR or mdns in NetworkManager.
Fixes #1870.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick 7f2eb1d87a net/tstun: fix TUN log spam when ACLs drop a packet
Whenever we dropped a packet due to ACLs, wireguard-go was logging:

Failed to write packet to TUN device: packet dropped by filter

Instead, just lie to wireguard-go and pretend everything is okay.

Fixes #1229

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 7629cd6120 net/tsaddr: add NewContainsIPFunc (move from wgengine)
I want to use this from netstack but it's not exported.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Josh Bleecher Snyder 42c8b9ad53 net/tstun: remove unnecessary break statement
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Brad Fitzpatrick 3237e140c4 tstest/integration: add testNode.AwaitListening, DERP+STUN, improve proxy trap
Updates #1840
4 years ago
Josh Bleecher Snyder 20e04418ff net/dns: add GOOS build tags
Fixes #1786

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
David Anderson bf9ef1ca27 net/dns: stop NetworkManager breaking v6 connectivity when setting DNS.
Tentative fix for #1699

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 72b6d98298 net/interfaces: return all Tailscale addresses from Tailscale().
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 44c2b7dc79 net/dns: on windows, skip site-local v6 resolvers.
Further refinement for tailscale/corp#1662.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Josh Bleecher Snyder 99705aa6b7 net/tstun: split TUN events channel into up/down and MTU
We had a long-standing bug in which our TUN events channel
was being received from simultaneously in two places.

The first is wireguard-go.

At wgengine/userspace.go:366, we pass e.tundev to wireguard-go,
which starts a goroutine (RoutineTUNEventReader)
that receives from that channel and uses events to adjust the MTU
and bring the device up/down.

At wgengine/userspace.go:374, we launch a goroutine that
receives from e.tundev, logs MTU changes, and triggers
state updates when up/down changes occur.

Events were getting delivered haphazardly between the two of them.

We don't really want wireguard-go to receive the up/down events;
we control the state of the device explicitly by calling device.Up.
And the userspace.go loop MTU logging duplicates logging that
wireguard-go does when it received MTU updates.

So this change splits the single TUN events channel into up/down
and other (aka MTU), and sends them to the parties that ought
to receive them.

I'm actually a bit surprised that this hasn't caused more visible trouble.
If a down event went to wireguard-go but the subsequent up event
went to userspace.go, we could end up with the wireguard-go device disappearing.

I believe that this may also (somewhat accidentally) be a fix for #1790.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
David Anderson 97d2fa2f56 net/dns: work around WSL DNS implementation flaws.
Fixes tailscale/corp#1662

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Avery Pennarun a92b9647c5 wgengine/bench: speed test for channels, sockets, and wireguard-go.
This tries to generate traffic at a rate that will saturate the
receiver, without overdoing it, even in the event of packet loss. It's
unrealistically more aggressive than TCP (which will back off quickly
in case of packet loss) but less silly than a blind test that just
generates packets as fast as it can (which can cause all the CPU to be
absorbed by the transmitter, giving an incorrect impression of how much
capacity the total system has).

Initial indications are that a syscall about every 10 packets (TCP bulk
delivery) is roughly the same speed as sending every packet through a
channel. A syscall per packet is about 5x-10x slower than that.

The whole tailscale wireguard-go + magicsock + packet filter
combination is about 4x slower again, which is better than I thought
we'd do, but probably has room for improvement.

Note that in "full" tailscale, there is also a tundev read/write for
every packet, effectively doubling the syscall overhead per packet.

Given these numbers, it seems like read/write syscalls are only 25-40%
of the total CPU time used in tailscale proper, so we do have
significant non-syscall optimization work to do too.

Sample output:

$ GOMAXPROCS=2 go test -bench . -benchtime 5s ./cmd/tailbench
goos: linux
goarch: amd64
pkg: tailscale.com/cmd/tailbench
cpu: Intel(R) Core(TM) i7-4785T CPU @ 2.20GHz
BenchmarkTrivialNoAlloc/32-2         	56340248	        93.85 ns/op	 340.98 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTrivialNoAlloc/124-2        	57527490	        99.27 ns/op	1249.10 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTrivialNoAlloc/1024-2       	52537773	       111.3 ns/op	9200.39 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTrivial/32-2                	41878063	       135.6 ns/op	 236.04 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTrivial/124-2               	41270439	       138.4 ns/op	 896.02 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTrivial/1024-2              	36337252	       154.3 ns/op	6635.30 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkBlockingChannel/32-2           12171654	       494.3 ns/op	  64.74 MB/s	         0 %lost	    1791 B/op	       0 allocs/op
BenchmarkBlockingChannel/124-2          12149956	       507.8 ns/op	 244.17 MB/s	         0 %lost	    1792 B/op	       1 allocs/op
BenchmarkBlockingChannel/1024-2         11034754	       528.8 ns/op	1936.42 MB/s	         0 %lost	    1792 B/op	       1 allocs/op
BenchmarkNonlockingChannel/32-2          8960622	      2195 ns/op	  14.58 MB/s	         8.825 %lost	    1792 B/op	       1 allocs/op
BenchmarkNonlockingChannel/124-2         3014614	      2224 ns/op	  55.75 MB/s	        11.18 %lost	    1792 B/op	       1 allocs/op
BenchmarkNonlockingChannel/1024-2        3234915	      1688 ns/op	 606.53 MB/s	         3.765 %lost	    1792 B/op	       1 allocs/op
BenchmarkDoubleChannel/32-2          	 8457559	       764.1 ns/op	  41.88 MB/s	         5.945 %lost	    1792 B/op	       1 allocs/op
BenchmarkDoubleChannel/124-2         	 5497726	      1030 ns/op	 120.38 MB/s	        12.14 %lost	    1792 B/op	       1 allocs/op
BenchmarkDoubleChannel/1024-2        	 7985656	      1360 ns/op	 752.86 MB/s	        13.57 %lost	    1792 B/op	       1 allocs/op
BenchmarkUDP/32-2                    	 1652134	      3695 ns/op	   8.66 MB/s	         0 %lost	     176 B/op	       3 allocs/op
BenchmarkUDP/124-2                   	 1621024	      3765 ns/op	  32.94 MB/s	         0 %lost	     176 B/op	       3 allocs/op
BenchmarkUDP/1024-2                  	 1553750	      3825 ns/op	 267.72 MB/s	         0 %lost	     176 B/op	       3 allocs/op
BenchmarkTCP/32-2                    	11056336	       503.2 ns/op	  63.60 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTCP/124-2                   	11074869	       533.7 ns/op	 232.32 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkTCP/1024-2                  	 8934968	       671.4 ns/op	1525.20 MB/s	         0 %lost	       0 B/op	       0 allocs/op
BenchmarkWireGuardTest/32-2          	 1403702	      4547 ns/op	   7.04 MB/s	        14.37 %lost	     467 B/op	       3 allocs/op
BenchmarkWireGuardTest/124-2         	  780645	      7927 ns/op	  15.64 MB/s	         1.537 %lost	     420 B/op	       3 allocs/op
BenchmarkWireGuardTest/1024-2        	  512671	     11791 ns/op	  86.85 MB/s	         0.5206 %lost	     411 B/op	       3 allocs/op
PASS
ok  	tailscale.com/wgengine/bench	195.724s

Updates #414.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
4 years ago
David Anderson f6b7d08aea net/dns: work around new NetworkManager in other selection paths.
Further bits of #1788

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 25ce9885a2 net/dns: don't use NM+resolved for NM >=1.26.6.
NetworkManager fixed the bug that forced us to use NetworkManager
if it's programming systemd-resolved, and in the same release also
made NetworkManager ignore DNS settings provided for unmanaged
interfaces... Which breaks what we used to do. So, with versions
1.26.6 and above, we MUST NOT use NetworkManager to indirectly
program systemd-resolved, but thankfully we can talk to resolved
directly and get the right outcome.

Fixes #1788

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick e41075dd4a net/interfaces: work around race fetching routing table
Fixes #1345
Updates golang/go#45736

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
David Anderson 30f5d706a1 net/dns/resolver: remove unnecessary/racy WaitGroup.
Fixes #1663

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 89c81c26c5 net/dns: fix resolved match domains when no nameservers are provided.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 4be26b269f net/dns: correctly capture all traffic in non-split configs.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson ca283ac899 net/dns: remove config in openresolv when given an empty DNS config.
Part of #1720.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago