Commit Graph

201 Commits

Author SHA1 Message Date
Brad Fitzpatrick
2ff481ff10 net/dns: add health check for particular broken-ish Linux DNS config
Updates #3937 (need to write docs before closing)

Change-Id: I1df7244cfbb0303481e2621ee750d21358bd67c6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-02-16 10:40:04 -08:00
Brad Fitzpatrick
c988bd6ed1 net/dns/resolvconffile: unify three /etc/resolv.conf parsers into new package
Change-Id: I2120893ca802d12f1bd0407d49077d3672627d33
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-02-14 20:55:57 -08:00
Brad Fitzpatrick
21358cf2f5 net/dns: slightly optimize dbusPing for non-dbus case [Linux]
Avoid some work when D-Bus isn't running.

Change-Id: I6f89bb75fdb24c13f61be9b400610772756db1ef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-02-11 14:00:54 -08:00
Brad Fitzpatrick
37e7a387ff net/dns: remove some unused code for detecting systemd-resolved [Linux]
Change-Id: I19c5fd2cdacfb9e5b688ccd9b4336ae4edffc445
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-02-11 14:00:54 -08:00
Brad Fitzpatrick
15599323a1 net/dns: fix systemd-resolved detection race at boot
If systemd-resolved is enabled but not running (or not yet running,
such as early boot) and resolv.conf is old/dangling, we weren't
detecting systemd-resolved.

This moves its ping earlier, which will trigger it to start up and
write its file.

Updates #3362 (likely fixes)
Updates #3531 (likely fixes)

Change-Id: I6392944ac59f600571c43b8f7a677df224f2beed
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-02-11 14:00:54 -08:00
Denton Gentry
dbea8217ac net/dns: add NetworkManager regression test
Use the exact /etc/resolv.conf file from a user report.
Updates https://github.com/tailscale/tailscale/issues/3531

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2022-02-10 15:01:49 -08:00
Aaron Bieber
e5cd765e00 net/dns/resolvd: properly handle not having "search" entries
This prevents adding an empty "search" line when no search domains are set.

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
2022-01-31 15:11:28 -08:00
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>
2022-01-24 11:51:23 -08:00
Brad Fitzpatrick
6feb8f4c51 net/dns: log why resolved does not look like it's on use [Linux]
Updates #3742
Updates #3531

Change-Id: I9fc7fa0f4bcab1cf8001ba92408c660a5b25f105
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-24 09:14:53 -08:00
Aaron Bieber
411c6c316c net/dns/resolvd: store nameservers
Currently only search domains are stored. This was an oversight
(under?) on my part.

As things are now, when MagicDNS is on and "Override local DNS" is
off, the dns forwarder has to timeout before names resolve. This
introduces a pretty annoying lang that makes everything feel
extremely slow. You will also see an error: "upstream nameservers
not set".

I tested with "Override local DNS" on and off. In both situations
things seem to function as expected (and quickly).

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
2022-01-19 21:17:31 -08:00
Brad Fitzpatrick
24a04d07d1 net/dns/resolver: handle tabs as whitespace when ExitDNS parses resolv.conf
On Synology, the /etc/resolv.conf has tabs in it, which this
resolv.conf parser (we have two, sigh) didn't handle.

Updates #3710

Change-Id: I86f8e09ad1867ee32fa211e85c382a27191418ea
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-12 12:38:48 -08:00
Brad Fitzpatrick
8df3fa4638 net/dns: make WSL network configuration opt-in for now
Tailscale seems to be breaking WSL configurations lately.  Until we
understand what changed, turn off Tailscale's involvement by default
and make it opt-in.

Updates #2815

Change-Id: I9977801f8debec7d489d97761f74000a4a33f71b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-11 10:10:21 -08:00
Aaron Bieber
189f359609
net/dns: teach OpenBSD's manager to talk to resolvd(8). (#2789)
OpenBSD 6.9 and up has a daemon which handles nameserver configuration. This PR
teaches the OpenBSD dns manager to check if resolvd is being used. If it is, it
will use the route(8) command to tell resolvd to add the Tailscale dns entries
to resolv.conf

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
2022-01-11 08:45:50 -08:00
Brad Fitzpatrick
8d0ed1c9ba net/dns/resolver: on Android, make ExitDNS use net package for DNS
Like Windows.

Updates #1738

Change-Id: I9f26bc58ce7e760c749786fbe5d9952c99eeb91c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-06 16:17:24 -08:00
Brad Fitzpatrick
506c727e30 ipnlocal, net/{dns,tsaddr,tstun}, wgengine: support MagicDNS on IPv6
Fixes #3660

RELNOTE=MagicDNS now works over IPv6 when CGNAT IPv4 is disabled.

Change-Id: I001e983df5feeb65289abe5012dedd177b841b45
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-04 14:37:22 -08:00
Brad Fitzpatrick
2513d2d728 net/{neterror,dns/resolver}: move PacketWasTruncated to neterror from DNS code
And delete the unused code in net/dns/resolver/neterr_*.go.

Change-Id: Ibe62c486bacce2733eb9968c96a98cbbdb2758bd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-01-03 14:03:30 -08:00
Brad Fitzpatrick
eb26c081b1 net/dns: bound time we wait on restarting systemd-resolved in another place
Fixes #3629
Updates #3537

Change-Id: I5d4b6acfcfdf0e3efcf6eb49c5e6cf4521e4baed
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-28 11:09:07 -08:00
Brad Fitzpatrick
0aa4c6f147 net/dns/resolver: add debug HTML handler to see what DNS traffic was forwarded
Change-Id: I6b790e92dcc608515ac8b178f2271adc9fd98f78
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-21 14:32:36 -08:00
Brad Fitzpatrick
0848b36dd2 net/dns/resolver: add metrics to PTR lookup misses
Updates tailscale/corp#3326

Change-Id: I58077d889a3b58ef0633267c92ffb265686ce152
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-19 09:50:16 -08:00
Brad Fitzpatrick
39f22a357d net/dns/resolver: send NXDOMAIN to iOS DNS-SD/Bonjour queries
Don't just ignore them. See if this makes them calm down.

Updates #3363

Change-Id: Id1d66308e26660d26719b2538b577522a1e36b63
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-18 19:24:19 -08:00
Brad Fitzpatrick
394c9de02b net/dns/resolver: add nameFromQuery benchmark
To convince me it's not as alloc-y as it looks.

Change-Id: I503a0cc267268a23d2973dfde9833c420be4e868
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-18 19:03:45 -08:00
Brad Fitzpatrick
c7052154d5 net/dns/resolver: fix the subject in a func comment
Change-Id: I519268c20dbd2c2da92da565839d3c1c84612dcc
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-18 15:11:01 -08:00
Brad Fitzpatrick
486059589b all: gofmt -w -s (simplify) tests
And it updates the build tag style on a couple files.

Change-Id: I84478d822c8de3f84b56fa1176c99d2ea5083237
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-15 08:43:41 -08:00
Brad Fitzpatrick
cced414c7d net/dns/resolver: add Windows ExitDNS service support, using net package
Updates #1713
Updates #835

Change-Id: Ia71e96d0632c2d617b401695ad68301b07c1c2ec
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-10 20:47:17 -08:00
Brad Fitzpatrick
cab5c46481 net/dns: bound how long we block looking for, restarting systemd-resolved
Fixes #3537

Change-Id: Iba6a3cde75983490d4072b5341f48dbfa2f997c0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-10 09:58:14 -08:00
Brad Fitzpatrick
c37af58ea4 net/tsdial: move more weirdo dialing into new tsdial package, plumb
Not done yet, but this move more of the outbound dial special casing
from random packages into tsdial, which aspires to be the one unified
place for all outbound dialing shenanigans.

Then this plumbs it all around, so everybody is ultimately
holding on to the same dialer.

As of this commit, macOS/iOS using an exit node should be able to
reach to the exit node's DoH DNS proxy over peerapi, doing the sockopt
to stay within the Network Extension.

A number of steps remain, including but limited to:

* move a bunch more random dialing stuff

* make netstack-mode tailscaled be able to use exit node's DNS proxy,
  teaching tsdial's resolver to use it when an exit node is in use.

Updates #1713

Change-Id: I1e8ee378f125421c2b816f47bc2c6d913ddcd2f5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-12-01 10:36:55 -08:00
Brad Fitzpatrick
3ae6f898cf ipn/ipnlocal, net/dns/resolver: use exit node's DoH proxy when available
Updates #1713

Change-Id: I3695a40ec12d2b4e6dac41cf4559daca6dddd68e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-30 17:01:09 -08:00
Aaron Klotz
f93cf6fa03 net/dns: fix checking for wrapped error when attempting to read wsl.conf for Windows WSL2
Fixes https://github.com/tailscale/tailscale/issues/3437

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-11-30 15:36:39 -07:00
David Anderson
124363e0ca net/dns: detect and decode UTF-16 from wsl.exe earlier.
Fixes #3170

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-30 13:10:18 -08:00
Brad Fitzpatrick
135580a5a8 tailcfg, ipn/ipnlocal, net/dns: forward exit node DNS on Unix to system DNS
Updates #1713

Change-Id: I4c073fec0992d9e01a9a4ce97087d5af0efdc68d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-29 15:25:41 -08:00
Brad Fitzpatrick
78b0bd2957 net/dns/resolver: add clientmetrics for DNS
Fixes tailscale/corp#1811

Change-Id: I864d11e0332a177e8c5ff403591bff6fec548f5a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-26 17:57:48 -08:00
Brad Fitzpatrick
25525b7754 net/dns/resolver, ipn/ipnlocal: wire up peerapi DoH server to DNS forwarder
Updates #1713

Change-Id: Ia4ed9d8c9cef0e70aa6d30f2852eaab80f5f695a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-23 18:59:36 -08:00
Josh Bleecher Snyder
d10cefdb9b net/dns: require space after nameserver/search parsing resolv.conf
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-11-23 15:11:46 -08:00
Josh Bleecher Snyder
9f00510833 net/dns: handle comments in resolv.conf
Currently, comments in resolv.conf cause our parser to fail,
with error messages like:

ParseIP("192.168.0.100 # comment"): unexpected character (at " # comment")

Fix that.

Noticed while looking through logs.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-11-23 15:11:46 -08:00
Brad Fitzpatrick
283ae702c1 ipn/ipnlocal: start adding DoH DNS server to peerapi when exit node
Updates #1713

Change-Id: I8d9c488f779e7acc811a9bc18166a2726198a429
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-23 08:21:41 -08:00
David Anderson
88b8a09d37 net/dns: make constants for the various DBus strings.
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-19 11:09:32 -08:00
David Anderson
6c82cebe57 health: add a health state for net/dns.OSConfigurator.
Lets the systemd-resolved OSConfigurator report health changes
for out of band config resyncs.

Updates #3327

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-19 11:09:32 -08:00
David Anderson
4ef3fed100 net/dns: resync config to systemd-resolved when it restarts.
Fixes #3327

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-19 11:09:32 -08:00
David Anderson
cf9169e4be net/dns: remove unused Config struct element.
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-19 11:09:32 -08:00
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>
2021-11-18 15:09:51 -08:00
Brad Fitzpatrick
400ed799e6 net/dns: work around old systemd-resolved setLinkDomain length limit
Don't set all the *.arpa. reverse DNS lookup domains if systemd-resolved
is old and can't handle them.

Fixes #3188

Change-Id: I283f8ce174daa8f0a972ac7bfafb6ff393dde41d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-11-16 12:54:21 -08:00
David Anderson
c5d572f371 net/dns: correctly handle NetworkManager-managed DNS that points to resolved.
Fixes #3304

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-11-15 12:21:25 -08:00
Josh Bleecher Snyder
94fb42d4b2 all: use testingutil.MinAllocsPerRun
There are a few remaining uses of testing.AllocsPerRun:
Two in which we only log the number of allocations,
and one in which dynamically calculate the allocations
target based on a different AllocsPerRun run.

This also allows us to tighten the "no allocs"
test in wgengine/filter.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-10-28 12:48:37 -07:00
Denton Gentry
139a6c4c9c net/dns: detect when resolvconf points to systemd-resolved.
There are /etc/resolv.conf files out there where resolvconf wrote
the file but pointed to systemd-resolved as the nameserver.
We're better off handling those as systemd-resolved.

> # Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
> #     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
> # 127.0.0.53 is the systemd-resolved stub resolver.
> # run "systemd-resolve --status" to see details about the actual nameservers.

Fixes https://github.com/tailscale/tailscale/issues/3026
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2021-10-26 18:00:31 -07:00
David Anderson
a320d70614 net/dns: fall back to copy+delete/truncate if moving to/from /etc/resolv.conf fails.
In some containers, /etc/resolv.conf is a bind-mount from outside the container.
This prevents renaming to or from /etc/resolv.conf, because it's on a different
filesystem from linux's perspective. It also prevents removing /etc/resolv.conf,
because doing so would break the bind-mount.

If we find ourselves within this environment, fall back to using copy+delete when
renaming to /etc/resolv.conf, and copy+truncate when renaming from /etc/resolv.conf.

Fixes #3000

Co-authored-by: Denton Gentry <dgentry@tailscale.com>
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-10-26 09:03:37 -07:00
David Anderson
04d24d3a38 net/dns: move directManager function below directManager's definition.
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-10-26 09:03:37 -07:00
David Anderson
422ea4980f net/dns: remove a tiny wrapper function that isn't contributing anything.
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-10-26 09:03:37 -07:00
Maxim Merzhanov
9f954628e5 net/dns: ignore UnknownMethod error in SetLinkDefaultRoute for resolved manager
Signed-off-by: Maxim Merzhanov <maksimmerzh@gmail.com>
2021-10-20 16:31:24 -07:00
Maisem Ali
7817ab6b20 net/dns/resolver: set maxDoHInFlight to 1000 on iOS 15+.
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2021-10-14 23:29:23 -04:00
David Crawshaw
77696579f5 net/dns/resolver: drop dropping log
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
2021-10-14 13:58:24 -07:00