Commit Graph

46 Commits (db83926121200a2a07263c5c5c0393c5a08a205c)

Author SHA1 Message Date
Tom acfe5bd33b
net/dns{., resolver}: time out DNS queries after 10 seconds (#4690)
Fixes https://github.com/tailscale/corp/issues/5198

The upstream forwarder will block indefinitely on `udpconn.ReadFrom` if no
reply is recieved, due to the lack of deadline on the connection object.

There still isn't a deadline on the connection object, but the automatic closing
of the context on deadline expiry will close the connection via `closeOnCtxDone`,
unblocking the read and resulting in a normal teardown.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Maisem Ali fd99c54e10 tailcfg,all: change structs to []*dnstype.Resolver
Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Tom d1d6ab068e
net/dns, wgengine: implement DNS over TCP (#4598)
* net/dns, wgengine: implement DNS over TCP

Signed-off-by: Tom DNetto <tom@tailscale.com>

* wgengine/netstack: intercept only relevant port/protocols to quad-100

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 2a0b5c21d2 net/dns/{., resolver}, wgengine: fix goroutine leak on shutdown
Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 7f45734663 assorted: documentation and readability fixes
This were intended to be pushed to #4408, but in my excitement I
forgot to git push :/ better late than never.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 5b85f848dd net/dns,net/dns/resolver: refactor channels/magicDNS out of Resolver
Moves magicDNS-specific handling out of Resolver & into dns.Manager. This
greatly simplifies the Resolver to solely issuing queries and returning
responses, without channels.

Enforcement of max number of in-flight magicDNS queries, assembly of
synthetic UDP datagrams, and integration with wgengine for
recieving/responding to magicDNS traffic is now entirely in Manager.
This path is being kept around, but ultimately aims to be deleted and
replaced with a netstack-based path.

This commit is part of a series to implement magicDNS using netstack.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Brad Fitzpatrick cc575fe4d6 net/dns: schedule DoH upgrade explicitly, fix Resolver.Addr confusion
Two changes in one:

* make DoH upgrades an explicitly scheduled send earlier, when we come
  up with the resolvers-and-delay send plan. Previously we were
  getting e.g.  four Google DNS IPs and then spreading them out in
  time (for back when we only did UDP) but then later we added DoH
  upgrading at the UDP packet layer, which resulted in sometimes
  multiple DoH queries to the same provider running (each doing happy
  eyeballs dialing to 4x IPs themselves) for each of the 4 source IPs.
  Instead, take those 4 Google/Cloudflare IPs and schedule 5 things:
  first the DoH query (which can use all 4 IPs), and then each of the
  4 IPs as UDP later.

* clean up the dnstype.Resolver.Addr confusion; half the code was
  using it as an IP string (as documented) as half was using it as
  an IP:port (from some prior type we used), primarily for tests.
  Instead, document it was being primarily an IP string but also
  accepting an IP:port for tests, then add an accessor method on it
  to get the IPPort and use that consistently everywhere.

Change-Id: Ifdd72b9e45433a5b9c029194d50db2b9f9217b53
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick d9efbd97cb net/dns: remove an unused function
Change-Id: I7c920c76223ffac37954ef2a18754afc52177598
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Tom 24bdcbe5c7
net/dns, net/dns/resolver, wgengine: refactor DNS request path (#4364)
* net/dns, net/dns/resolver, wgengine: refactor DNS request path

Previously, method calls into the DNS manager/resolver types handled DNS
requests rather than DNS packets. This is fine for UDP as one packet
corresponds to one request or response, however will not suit an
implementation that supports DNS over TCP.

To support PRs implementing this in the future, wgengine delegates
all handling/construction of packets to the magic DNS endpoint, to
the DNS types themselves. Handling IP packets at this level enables
future support for both UDP and TCP.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
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>
3 years ago
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>
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 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 cf9169e4be net/dns: remove unused Config struct element.
Signed-off-by: David Anderson <danderson@tailscale.com>
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
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
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
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
David Crawshaw 297b3d6fa4 staticcheck.conf: turn off noisy lint errors
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 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 97d2fa2f56 net/dns: work around WSL DNS implementation flaws.
Fixes tailscale/corp#1662

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 158328ba24 net/dns: remove ForceSplitDNSForTesting.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson bb0710d51d net/dns: add debugging traces to DNS manager selection on linux.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 854d5d36a1 net/dns: return error from NewOSManager, use it to initialize NM.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 1a371b93be util/dnsname: add FQDN type, use throughout codebase.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 2685260ba1 net/dns: add temporary fallback to quad-9 resolver for split-DNS testing.
This allows split-DNS configurations to not break clients on OSes that
haven't yet been ported to understand split DNS, by falling back to quad-9
as a global resolver when handed an "impossible to implement"
split-DNS config.

Part of #953. Needs to be removed before shipping 1.8.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson b9e194c14b net/dns: add missing FQDN qualification.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson b74a8994ca net/dns: make FQDN dot style consistent in more places.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 4a64d2a603 net/dns: some post-review cleanups.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 720c1ad0f0 net/dns: insert OS base config when emulating split DNS.
Part of #953.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson da4cc8bbb4 net/dns: handle all possible translations of high-level DNS config.
With this change, all OSes can sort-of do split DNS, except that the
default upstream is hardcoded to 8.8.8.8 pending further plumbing.
Additionally, Windows 8-10 can do split DNS fully correctly, without
the 8.8.8.8 hack.

Part of #953.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson e0e677a8f6 net/dns: split out search domains and match domains in OSConfig.
It seems that all the setups that support split DNS understand
this distinction, and it's an important one when translating
high-level configuration.

Part of #953.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson c16a926bf2 net/dns: set OSConfig.Primary.
OS implementations are going to support split DNS soon.
Until they're all in place, hardcode Primary=true to get
the old behavior.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson b2a597b288 net/dns: rename Set to SetDNS in OSConfigurator.
wgengine/router.CallbackRouter needs to support both the Router
and OSConfigurator interfaces, so the setters can't both be called
Set.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 7d84ee6c98 net/dns: unify the OS manager and internal resolver.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 6a206fd0fb net/dns: rename impl to os.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 4c61ebacf4 wgengine: move DNS configuration out of wgengine/router.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson befd8e4e68 net/dns: replace managerImpl with OSConfigurator in code.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 8af9d770cf net/dns: rename Config to OSConfig.
Making way for a new higher level config struct.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson fcfc0d3a08 net/dns: remove ManagerConfig, pass relevant args directly.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 95470c3448 net/dns: remove Cleanup manager parameter.
It's only use to skip some optional initialization during cleanup,
but that work is very minor anyway, and about to change drastically.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson cf361bb9b1 net/dns: remove PerDomain from Config.
It's currently unused, and no longer makes sense with the upcoming
DNS infrastructure. Keep it in tailcfg for now, since we need protocol
compat for a bit longer.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson f77ba75d6c wgengine/router: move DNS cleanup into the DNS package.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 9f7f2af008 wgengine/router/dns: move to net/dns.
Preparation for merging the APIs and whatnot.

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