Commit Graph

172 Commits (a54d13294f9a995f860099430d56acf05377a9e3)

Author SHA1 Message Date
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>
3 years ago
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>
3 years ago
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>
3 years ago
Josh Bleecher Snyder d10cefdb9b net/dns: require space after nameserver/search parsing resolv.conf
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
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>
3 years ago
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>
3 years ago
David Anderson 88b8a09d37 net/dns: make constants for the various DBus strings.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
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>
3 years ago
David Anderson 4ef3fed100 net/dns: resync config to systemd-resolved when it restarts.
Fixes #3327

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson cf9169e4be net/dns: remove unused Config struct element.
Signed-off-by: David Anderson <danderson@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
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>
3 years ago
David Anderson c5d572f371 net/dns: correctly handle NetworkManager-managed DNS that points to resolved.
Fixes #3304

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
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>
3 years ago
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>
3 years ago
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>
3 years ago
David Anderson 04d24d3a38 net/dns: move directManager function below directManager's definition.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 422ea4980f net/dns: remove a tiny wrapper function that isn't contributing anything.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Maxim Merzhanov 9f954628e5 net/dns: ignore UnknownMethod error in SetLinkDefaultRoute for resolved manager
Signed-off-by: Maxim Merzhanov <maksimmerzh@gmail.com>
3 years ago
Maisem Ali 7817ab6b20 net/dns/resolver: set maxDoHInFlight to 1000 on iOS 15+.
Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
David Crawshaw 77696579f5 net/dns/resolver: drop dropping log
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Brad Fitzpatrick 676fb458c3 net/dns/resolver: make hasRDNSBonjourPrefix match shorter queries too
Fixes tailscale/corp#2886
Updates tailscale/corp#2820
Updates #2442

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
nicksherron f01ff18b6f all: fix spelling mistakes
Signed-off-by: nicksherron <nsherron90@gmail.com>
3 years ago
Smitty b382161fe5 tsdns: don't forward transient DNS errors
When a DNS server claims to be unable or unwilling to handle a request,
instead of passing that refusal along to the client, just treat it as
any other error trying to connect to the DNS server. This prevents DNS
requests from failing based on if a server can respond with a transient
error before another server is able to give an actual response. DNS
requests only failing *sometimes* is really hard to find the cause of
(#1033).

Signed-off-by: Smitty <me@smitop.com>
3 years ago
Denton Gentry d883747d8b net/dns/resolver: don't forward DNS-SD on all platforms
We added the initial handling only for macOS and iOS.
With 1.16.0 now released, suppress forwarding DNS-SD
on all platforms to test it through the 1.17.x cycle.

Updates #2442

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Brad Fitzpatrick 297d1b7cb6 net/dns/resolver: don't forward DNS-SD queries
Updates #2442
Fixes tailscale/corp#2820

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 47044f3af7 net/dns/resolver: fix log prefix
The passed in logf already has a "dns: " prefix so they were
doubled up.
3 years ago
Brad Fitzpatrick 7634af5c6f all: gofmt
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Filippo Valsorda d7ce2be5f4 net/dns/resolver: add unsecured Quad9 resolvers
DNSSEC is an availability issue, as recently demonstrated by the
Slack issue, with limited security advantage. DoH on the other hand
is a critical security upgrade. This change adds DoH support for the
non-DNSSEC endpoints of Quad9.

https://www.quad9.net/service/service-addresses-and-features#unsec
Signed-off-by: Filippo Valsorda <hi@filippo.io>
3 years ago
Denton Gentry 93c2882a2f wgengine: flush DNS cache after major link change.
Windows has a public dns.Flush used in router_windows.go.
However that won't work for platforms like Linux, where
we need a different flush mechanism for resolved versus
other implementations.

We're instead adding a FlushCaches method to the dns Manager,
which can be made to work on all platforms as needed.

Fixes https://github.com/tailscale/tailscale/issues/2132

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Maxim Merzhanov d43fcd2f02 net/dns: fix error wrapping for SetLinkDefaultRoute in resolved
Signed-off-by: Maxim Merzhanov <maksimmerzh@gmail.com>
3 years ago
Brad Fitzpatrick 640134421e all: update tests to use tstest.MemLogger
And give MemLogger a mutex, as one caller had, which does match the logf
contract better.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Crawshaw 9502b515f1 net/dns: replace resolver IPs with type for DoH
We currently plumb full URLs for DNS resolvers from the control server
down to the client. But when we pass the values into the net/dns
package, we throw away any URL that isn't a bare IP. This commit
continues the plumbing, and gets the URL all the way to the built in
forwarder. (It stops before plumbing URLs into the OS configurations
that can handle them.)

For #2596

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
David Anderson bb6fdfb243 net/dns: fix the build on freebsd (missing default case in switch)
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
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
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
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
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
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
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