367 Commits (808b4139eec4f9ffcf8fc7a39b0519395efcc165)

Author	SHA1	Message	Date
Andrew Dunham	286c6ce27c	net/dns/resolver: race UDP and TCP queries (#9544) ... Instead of just falling back to making a TCP query to an upstream DNS server when the UDP query returns a truncated query, also start a TCP query in parallel with the UDP query after a given race timeout. This ensures that if the upstream DNS server does not reply over UDP (or if the response packet is blocked, or there's an error), we can still make queries if the server replies to TCP queries. This also adds a new package, util/race, to contain the logic required for racing two different functions and returning the first non-error answer. Updates tailscale/corp#14809 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I4311702016c1093b1beaa31b135da1def6d86316	1 year ago
Andrew Dunham	530aaa52f1	net/dns: retry forwarder requests over TCP ... We weren't correctly retrying truncated requests to an upstream DNS server with TCP. Instead, we'd return a truncated request to the user, even if the user was querying us over TCP and thus able to handle a large response. Also, add an envknob and controlknob to allow users/us to disable this behaviour if it turns out to be buggy (✨ DNS ✨). Updates #9264 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: Ifb04b563839a9614c0ba03e9c564e8924c1a2bfd	1 year ago
Brad Fitzpatrick	3b32d6c679	wgengine/magicsock, controlclient, net/dns: reduce some logspam ... Updates #cleanup Change-Id: I78b0697a01e94baa33f3de474b591e616fa5e6af Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
James Tucker	1c88a77f68	net/dns/publicdns: update Quad9 addresses and references ... One Quad9 IPv6 address was incorrect, and an additional group needed adding. Additionally I checked Cloudflare and included source reference URLs for both. Updates #cleanup Signed-off-by: James Tucker <james@tailscale.com>	1 year ago
James Tucker	4c693d2ee8	net/dns/publicdns: update Mullvad DoH server list ... The following IPs are not used anymore: 193.19.108.2 and 193.19.108.3. All of the servers are now named consistently under dns.mullvad.net. Several new servers were added. https://mullvad.net/en/help/dns-over-https-and-dns-over-tls/ Updates #5416 Updates #9345 Signed-off-by: James Tucker <james@tailscale.com>	1 year ago
Brad Fitzpatrick	dc7aa98b76	all: use set.Set consistently instead of map[T]struct{} ... I didn't clean up the more idiomatic map[T]bool with true values, at least yet. I just converted the relatively awkward struct{}-valued maps. Updates #cleanup Change-Id: I758abebd2bb1f64bc7a9d0f25c32298f4679c14f Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
Andrew Dunham	d413dd7ee5	net/dns/publicdns: add support for Wikimedia DNS ... RELNOTE=Adds support for Wikimedia DNS Updates #9255 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I4213c29e0f91ea5aa0304a5a026c32b6690fead9	1 year ago
Brad Fitzpatrick	11ece02f52	net/{interfaces,netmon}: remove "interesting", EqualFiltered API ... This removes a lot of API from net/interfaces (including all the filter types, EqualFiltered, active Tailscale interface func, etc) and moves the "major" change detection to net/netmon which knows more about the world and the previous/new states. Updates #9040 Change-Id: I7fe66a23039c6347ae5458745b709e7ebdcce245 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
Brad Fitzpatrick	e8551d6b40	all: use Go 1.21 slices, maps instead of x/exp/{slices,maps} ... Updates #8419 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
Brad Fitzpatrick	be4eb6a39e	derp, net/dns/recursive: use Go 1.21 min ... Updates #8419 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
David Anderson	52212f4323	all: update exp/slices and fix call sites ... slices.SortFunc suffered a late-in-cycle API breakage. Updates #cleanup Signed-off-by: David Anderson <danderson@tailscale.com>	1 year ago
Michael Stapelberg	2a6c237d4c	net/dns: overwrite /tmp/resolv.conf on gokrazy ... Appliances built using https://gokrazy.org/ have a read-only root file system, including /etc/resolv.conf, which is a symlink to /tmp/resolv.conf. The system’s dhcp client overwrites /tmp/resolv.conf instead, so we need to use this path in Tailscale, too. related to https://github.com/gokrazy/gokrazy/issues/209 fixes https://github.com/tailscale/tailscale/issues/8689 Signed-off-by: Michael Stapelberg <michael@stapelberg.de>	1 year ago
Anton Tolchanov	388b124513	net/dns: detect when libnss_resolve is used ... Having `127.0.0.53` is not the only way to use `systemd-resolved`. An alternative way is to enable `libnss_resolve` module, which seems to now be used by default on Debian 12 bookworm. Fixes #8549 Signed-off-by: Anton Tolchanov <anton@tailscale.com>	1 year ago
Adrian Dewhurst	cd4c71c122	tstest: prepare for Clock API changes ... This change introduces tstime.NewClock and tstime.ClockOpts as a new way to construct tstime.Clock. This is a subset of #8464 as a stepping stone so that we can update our internal code to use the new API before making the second round of changes. Updates #8463 Change-Id: Ib26edb60e5355802aeca83ed60e4fdf806c90e27 Signed-off-by: Adrian Dewhurst <adrian@tailscale.com>	1 year ago
Brad Fitzpatrick	a874f1afd8	all: adjust case of "IPv4" and "IPv6" ... Updates #docs Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	1 year ago
Andrew Dunham	b6d20e6f8f	go.mod, net/dns/recursive: update github.com/miekg/dns ... Updates #cleanup Change-Id: If4de6a84448a17dd81cc2a8af788bd18c3d0bbe3 Signed-off-by: Andrew Dunham <andrew@du.nham.ca>	1 year ago
Andrew Dunham	f077b672e4	net/dns/recursive: add initial implementation of recursive DNS resolver ... We've talked in the past about reworking how bootstrap DNS works to instead do recursive DNS resolution from the root; this would better support on-prem customers and Headscale users where the DERP servers don't currently resolve their DNS server. This package is an initial implementation of recursive resolution for A and AAAA records. Updates #5853 Change-Id: Ibe974d78709b4b03674b47c4ef61f9a00addf8b4 Signed-off-by: Andrew Dunham <andrew@du.nham.ca>	1 year ago
Mihai Parparita	7330aa593e	all: avoid repeated default interface lookups ... On some platforms (notably macOS and iOS) we look up the default interface to bind outgoing connections to. This is both duplicated work and results in logspam when the default interface is not available (i.e. when a phone has no connectivity, we log an error and thus cause more things that we will try to upload and fail). Fixed by passing around a netmon.Monitor to more places, so that we can use its cached interface state. Fixes #7850 Updates #7621 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	4722f7e322	all: move network monitoring from wgengine/monitor to net/netmon ... We're using it in more and more places, and it's not really specific to our use of Wireguard (and does more just link/interface monitoring). Also removes the separate interface we had for it in sockstats -- it's a small enough package (we already pull in all of its dependencies via other paths) that it's not worth the extra complexity. Updates #7621 Updates #7850 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Andrew Dunham	f85dc6f97c	ci: add more lints (#7909) ... This is a follow-up to #7905 that adds two more linters and fixes the corresponding findings. As per the previous PR, this only flags things that are "obviously" wrong, and fixes the issues found. Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I8739bdb7bc4f75666a7385a7a26d56ec13741b7c	2 years ago
Andrew Dunham	280255acae	various: add golangci-lint, fix issues (#7905) ... This adds an initial and intentionally minimal configuration for golang-ci, fixes the issues reported, and adds a GitHub Action to check new pull requests against this linter configuration. Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I8f38fbc315836a19a094d0d3e986758b9313f163	2 years ago
Brad Fitzpatrick	10f1c90f4d	wgengine/magicsock, types/nettype, etc: finish ReadFromUDPAddrPort netip migration ... So we're staying within the netip.Addr/AddrPort consistently and avoiding allocs/conversions to the legacy net addr types. Updates #5162 Change-Id: I59feba60d3de39f773e68292d759766bac98c917 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Mihai Parparita	edb02b63f8	net/sockstats: pass in logger to sockstats.WithSockStats ... Using log.Printf may end up being printed out to the console, which is not desirable. I noticed this when I was investigating some client logs with `sockstats: trace "NetcheckClient" was overwritten by another`. That turns to be harmless/expected (the netcheck client will fall back to the DERP client in some cases, which does its own sockstats trace). However, the log output could be visible to users if running the `tailscale netcheck` CLI command, which would be needlessly confusing. Updates tailscale/corp#9230 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Andrew Dunham	33b359642e	net/dns: don't send on closed channel in resolvedManager ... Fixes #7686 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: Ibffb05539ab876b12407d77dcf2201d467895981	2 years ago
Andrew Dunham	83fa17d26c	various: pass logger.Logf through to more places ... Updates #7537 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: Id89acab70ea678c8c7ff0f44792d54c7223337c6	2 years ago
Mihai Parparita	6ac6ddbb47	sockstats: switch label to enum ... Makes it cheaper/simpler to persist values, and encourages reuse of labels as opposed to generating an arbitrary number. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Aaron Klotz	9687f3700d	net/dns: deal with Windows wsl.exe hangs ... Despite the fact that WSL configuration is still disabled by default, we continue to log the machine's list of WSL distros as a diagnostic measure. Unfortunately I have seen the "wsl.exe -l" command hang indefinitely. This patch adds a (more than reasonable) 10s timeout to ensure that tailscaled does not get stuck while executing this operation. I also modified the Windows implementation of NewOSConfigurator to do the logging asynchronously, since that information is not required in order to continue starting up. Fixes #7476 Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
Maisem Ali	1a30b2d73f	all: use tstest.Replace more ... Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Mihai Parparita	9cb332f0e2	sockstats: instrument networking code paths ... Uses the hooks added by tailscale/go#45 to instrument the reads and writes on the major code paths that do network I/O in the client. The convention is to use "<package>.<type>:<label>" as the annotation for the responsible code path. Enabled on iOS, macOS and Android only, since mobile platforms are the ones we're most interested in, and we are less sensitive to any throughput degradation due to the per-I/O callback overhead (macOS is also enabled for ease of testing during development). For now just exposed as counters on a /v0/sockstats PeerAPI endpoint. We also keep track of the current interface so that we can break out the stats by interface. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
David Anderson	8b2ae47c31	version: unexport all vars, turn Short/Long into funcs ... The other formerly exported values aren't used outside the package, so just unexport them. Signed-off-by: David Anderson <danderson@tailscale.com>	2 years ago
Mihai Parparita	0e3fb91a39	net/dns/resolver: remove maxDoHInFlight ... It was originally added to control memory use on iOS (#2490), but then was relaxed conditionally when running on iOS 15 (#3098). Now that we require iOS 15, there's no need for the limit at all, so simplify back to the original state. Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Andrew Dunham	880a41bfcc	net/dns/resolver: add envknob to debug exit node DNS queries on on Windows ... Add the envknob TS_DEBUG_EXIT_NODE_DNS_NET_PKG, which enables more verbose debug logging when calling the handleExitNodeDNSQueryWithNetPkg function. This function is currently only called on Windows and Android. Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: Ieb3ca7b98837d7dc69cd9ca47609c1c52e3afd7b	2 years ago
Brad Fitzpatrick	b1248442c3	all: update to Go 1.20, use strings.CutPrefix/Suffix instead of our fork ... Updates #7123 Updates #5309 Change-Id: I90bcd87a2fb85a91834a0dd4be6e03db08438672 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Will Norris	71029cea2d	all: update copyright and license headers ... This updates all source files to use a new standard header for copyright and license declaration. Notably, copyright no longer includes a date, and we now use the standard SPDX-License-Identifier header. This commit was done almost entirely mechanically with perl, and then some minimal manual fixes. Updates #6865 Signed-off-by: Will Norris <will@tailscale.com>	2 years ago
Brad Fitzpatrick	3addcacfe9	net/dns: fix recently added URL scheme from http to https ... I typoed/brainoed in the earlier 3582628691 Change-Id: Ic198a6f9911f195d9da9fc5259b5784a4b15e5e3 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	3582628691	net/dns/resolvconffile: link to FAQ about resolv.conf being overwritten ... Add link to new http://tailscale.com/s/resolvconf-overwrite page, added in tailscale/tailscale-www#2243 Change-Id: I9718399487f2ed18bf1a112581fd168aea30f232 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Tom DNetto	673b3d8dbd	net/dns,userspace: remove unused DNS paths, normalize query limit on iOS ... With a42a594bb3, iOS uses netstack and hence there are no longer any platforms which use the legacy MagicDNS path. As such, we remove it. We also normalize the limit for max in-flight DNS queries on iOS (it was 64, now its 256 as per other platforms). It was 64 for the sake of being cautious about memory, but now we have 50Mb (iOS-15 and greater) instead of 15Mb so we have the spare headroom. Signed-off-by: Tom DNetto <tom@tailscale.com>	2 years ago
Brad Fitzpatrick	ea70aa3d98	net/dns/resolvconffile: fix handling of multiple search domains ... Fixes #6875 Change-Id: I57eb9312c9a1c81792ce2b5a0a0f254213b05df2 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Andrew Dunham	0372e14d79	net/dns: bump DNS-over-TCP size limit to 4k ... We saw a few cases where we hit this limit; bumping to 4k seems relatively uncontroversial. Change-Id: I218fee3bc0d2fa5fde16eddc36497a73ebd7cbda Signed-off-by: Andrew Dunham <andrew@du.nham.ca>	2 years ago
Andrew Dunham	3f4d51c588	net/dns: don't send on closed channel when message too large ... Previously, if a DNS-over-TCP message was received while there were existing queries in-flight, and it was over the size limit, we'd close the 'responses' channel. This would cause those in-flight queries to send on the closed channel and panic. Instead, don't close the channel at all and rely on s.ctx being canceled, which will ensure that in-flight queries don't hang. Fixes #6725 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I8267728ac37ed7ae38ddd09ce2633a5824320097	2 years ago
Brad Fitzpatrick	ca08e316af	util/endian: delete package; use updated josharian/native instead ... See josharian/native#3 Updates golang/go#57237 Change-Id: I238c04c6654e5b9e7d9cfb81a7bbc5e1043a84a2 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Maisem Ali	99aa335923	net/dns: [linux] log and add metric for dnsMode ... I couldn't find any logs that indicated which mode it was running in so adding that. Also added a gauge metric for dnsMode. Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Andrew Dunham	ec790e58df	net/dns: retry overwriting hosts file on Windows ... Updates #5753 Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I60f81bd3325d5ba5383b947c7a7aaa5b14e460f6	2 years ago
Mihai Parparita	33520920c3	all: use strs.CutPrefix and strs.CutSuffix more ... Updates places where we use HasPrefix + TrimPrefix to use the combined function. Updates #5309 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Aaron Klotz	41e1d336cc	net/dns: change windows DNS manager to use pointer receiver ... This is safer given that we need to close the NRPT database. Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
Brad Fitzpatrick	90bd74fc05	net/dns: add a health warning when Linux /etc/resolv.conf is overwritten ... Change-Id: I925b4d904bc7ed920bc5afee11e6dcb2ffc2fbfd Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	001f482aca	net/dns: make "direct" mode on Linux warn on resolv.conf fights ... Run an inotify goroutine and watch if another program takes over /etc/inotify.conf. Log if so. For now this only logs. In the future I want to wire it up into the health system to warn (visible in "tailscale status", etc) about the situation, with a short URL to more info about how you should really be using systemd-resolved if you want programs to not fight over your DNS files on Linux. Updates #4254 etc etc Change-Id: I86ad9125717d266d0e3822d4d847d88da6a0daaa Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	66b4a363bd	net/dns/resolver: add yet another 4via6 DNS form that's hopefully more robust ... $ dig +short @100.100.100.100 aaaa 10-2-5-3-via-7.foo-bar.ts.net fd7a:115c:a1e0:b1a:0:7:a02:503 $ dig +short @100.100.100.100 aaaa 10-2-5-3-via-7 fd7a:115c:a1e0:b1a:0:7:a02:503 $ ping 10-2-5-3-via-7 PING 10-2-5-3-via-7(fd7a:115c:a1e0:b1a:0:7:a02:503 (fd7a:115c:a1e0:b1a:0:7:a02:503)) 56 data bytes ... Change-Id: Ice8f954518a6a2fca8b2c04da7f31f61d78cdec4 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	da8def8e13	all: remove old +build tags ... The //go:build syntax was introduced in Go 1.17: https://go.dev/doc/go1.17#build-lines gofmt has kept the +build and go:build lines in sync since then, but enough time has passed. Time to remove them. Done with: perl -i -npe 's,^// \+build.*\n,,' $(git grep -l -F '+build') Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Anton Tolchanov	e25ab75795	net/dns: getting base DNS config is not supported on macOS ... Instead of returning a custom error, use ErrGetBaseConfigNotSupported that seems to be intended for this use case. This fixes DNS resolution on macOS clients compiled from source. Signed-off-by: Anton Tolchanov <anton@tailscale.com>	2 years ago
Andrew Dunham	e966f024b0	net/dns: print systemd-resolved ResolvConfMode ... The ResolvConfMode property is documented to return how systemd-resolved is currently managing /etc/resolv.conf. Include that information in the debug line, when available, to assist in debugging DNS issues. Signed-off-by: Andrew Dunham <andrew@du.nham.ca> Change-Id: I1ae3a257df1d318d0193a8c7f135c458ec45093e	2 years ago
Maisem Ali	3555a49518	net/dns: always attempt to read the OS config on macOS/iOS ... Also reconfigure DNS on iOS/macOS on link changes. Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Mihai Parparita	8343b243e7	all: consistently initialize Logf when creating tsdial.Dialers ... Most visible when using tsnet.Server, but could have resulted in dropped messages in a few other places too. Fixes #5743 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Josh Soref	d4811f11a0	all: fix spelling mistakes ... Signed-off-by: Josh Soref <2119212+jsoref@users.noreply.github.com>	2 years ago
Brad Fitzpatrick	bb7be74756	net/dns/publicdns: permit more NextDNS profile bits in its IPv6 suffix ... I brain-o'ed the math earlier. The NextDNS prefix is /32 (actually /33, but will guarantee last bit is 0), so we have 128-32 = 96 bits (12 bytes) of config/profile ID that we can extract. NextDNS doesn't currently use all those, but might. Updates #2452 Change-Id: I249bd28500c781e45425fd00fd3f46893ae226a2 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Andrew Dunham	a5fab23e8f	net/dns: format OSConfig correctly with no pointers (#5766) ... Fixes tailscale/tailscale#5669 Signed-off-by: Andrew Dunham <andrew@du.nham.ca>	2 years ago
Eng Zer Jun	f0347e841f	refactor: move from io/ioutil to io and os packages ... The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit replaces the existing io/ioutil functions with their new definitions in io and os packages. Reference: https://golang.org/doc/go1.16#ioutil Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>	2 years ago
Brad Fitzpatrick	74674b110d	envknob: support changing envknobs post-init ... Updates #5114 Change-Id: Ia423fc7486e1b3f3180a26308278be0086fae49b Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Mihai Parparita	82e82d9b7a	net/dns/resolver: remove unused responseTimeout constant ... Timeout is now enforced elsewhere, see discussion in https://github.com/tailscale/tailscale/pull/4408#discussion_r970092333. Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
nyghtowl	0f16640546	net/dns: fix fmt error on Revert print ... Fixes #5619 Signed-off-by: nyghtowl <warrick@tailscale.com>	2 years ago
Brad Fitzpatrick	708b7bff3d	net/dns/publicdns: also support NextDNS DoH query parameters ... The plan has changed. Doing query parameters rather than path + heades. NextDNS added support for query parameters. Updates #2452 Change-Id: I4783c0a06d6af90756d9c80a7512644ba702388c Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	e7376aca25	net/dns/resolver: set DNS-over-HTTPS Accept and User-Agent header on requests ... Change-Id: I14b821771681e70405a507f43229c694159265ff Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	c14361e70e	net/dns/publicdns: support NextDNS DoH URLs with path parameters ... Updates #2452 Change-Id: I0f1c34cc1672e87e7efd0adfe4088724dd0de3ed Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	2aade349fc	net/dns, types/dnstypes: update some comments, tests for DoH ... Clarify & verify that some DoH URLs can be sent over tailcfg in some limited cases. Updates #2452 Change-Id: Ibb25db77788629c315dc26285a1059a763989e24 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	58abae1f83	net/dns/{publicdns,resolver}: add NextDNS DoH support ... NextDNS is unique in that users create accounts and then get user-specific DNS IPs & DoH URLs. For DoH, the customer ID is in the URL path. For IPv6, the IP address includes the customer ID in the lower bits. For IPv4, there's a fragile "IP linking" mechanism to associate your public IPv4 with an assigned NextDNS IPv4 and that tuple maps to your customer ID. We don't use the IP linking mechanism. Instead, NextDNS is DoH-only. Which means using NextDNS necessarily shunts all DNS traffic through 100.100.100.100 (programming the OS to use 100.100.100.100 as the global resolver) because operating systems can't usually do DoH themselves. Once it's in Tailscale's DoH client, we then connect out to the known NextDNS IPv4/IPv6 anycast addresses. If the control plane sends the client a NextDNS IPv6 address, we then map it to the corresponding NextDNS DoH with the same client ID, and we dial that DoH server using the combination of v4/v6 anycast IPs. Updates #2452 Change-Id: I3439d798d21d5fc9df5a2701839910f5bef85463 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	9bd9f37d29	go.mod: bump wireguard/windows, which moves to using net/netip ... Updates #5162 Change-Id: If99a3f0000bce0c01bdf44da1d513f236fd7cdf8 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	9f6c8517e0	net/dns: set OS DNS to 100.100.100.100 for route-less ExtraRecords [cap 41] ... If ExtraRecords (Hosts) are specified without a corresponding split DNS route and global DNS is specified, then program the host OS DNS to use 100.100.100.100 so it can blend in those ExtraRecords. Updates #1543 Change-Id: If49014a5ecc8e38978ff26e54d1f74fe8dbbb9bc Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Maisem Ali	68d9d161f4	net/dns: [win] fix regression in disableDynamicUpdate ... Somehow I accidentally set the wrong registry value here. It should be DisableDynamicUpdate=1 and not EnableDNSUpdate=0. This is a regression from 545639e. Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Nahum Shalman	214242ff62	net/dns/publicdns: Add Mullvad DoH ... See https://mullvad.net/en/help/dns-over-https-and-dns-over-tls/ The Mullvad DoH servers appear to only speak HTTP/2 and the use of a non-nil DialContext in the http.Transport means that ForceAttemptHTTP2 must be set to true to be able to use them. Signed-off-by: Nahum Shalman <nahamu@gmail.com>	2 years ago
Maisem Ali	9197dd14cc	net/dns: [win] add MagicDNS entries to etc/hosts ... This works around the 2.3s delay in short name lookups when SNR is enabled. C:\Windows\System32\drivers\etc\hosts file. We only add known hosts that match the search domains, and we populate the list in order of Search Domains so that our matching algorithm mimics what Windows would otherwise do itself if SNR was off. Updates #1659 Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	25865f81ee	net/dns: disable NetBIOS on Tailscale interfaces ... Like LLMNR, NetBIOS also adds resolution delays and we don't support it anyway so just disable it on the interface. Updates #1659 Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	545639ee44	util/winutil: consolidate interface specific registry keys ... Code movement to allow reuse in a follow up PR. Updates #1659 Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	1cff719015	net/dns: [win] respond with SERVFAIL queries when no resolvers ... Currently we forward unmatched queries to the default resolver on Windows. This results in duplicate queries being issued to the same resolver which is just wasted. Updates #1659 Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	3bb57504af	net/dns/resolver: add comments clarifying nil error returns ... Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	4497bb0b81	net/dns/resolver: return SERVFAIL when no upstream resolvers set ... Otherwise we just keep looping over the same thing again and again. ``` dns udp query: upstream nameservers not set dns udp query: upstream nameservers not set dns udp query: upstream nameservers not set ``` Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	a9f6cd41fd	all: use syncs.AtomicValue ... Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Maisem Ali	9bb5a038e5	all: use atomic.Pointer ... Also add some missing docs. Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Brad Fitzpatrick	8725b14056	all: migrate more code code to net/netip directly ... Instead of going through the tailscale.com/net/netaddr transitional wrappers. Updates #5162 Change-Id: I3dafd1c2effa1a6caa9b7151ecf6edd1a3fda3dd Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	116f55ff66	all: gofmt for Go 1.19 ... Updates #5210 Change-Id: Ib02cd5e43d0a8db60c1f09755a8ac7b140b670be Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
nyghtowl	e6e1976c3a	net/dns: remove systemd-resolved ping ... Ping only needed to ensure system awak otherwise utilizing resolvConf to set dns mode. Signed-off-by: nyghtowl <warrick@tailscale.com>	2 years ago
Brad Fitzpatrick	a12aad6b47	all: convert more code to use net/netip directly ... perl -i -npe 's,netaddr.IPPrefixFrom,netip.PrefixFrom,' $(git grep -l -F netaddr.) perl -i -npe 's,netaddr.IPPortFrom,netip.AddrPortFrom,' $(git grep -l -F netaddr. ) perl -i -npe 's,netaddr.IPPrefix,netip.Prefix,g' $(git grep -l -F netaddr. ) perl -i -npe 's,netaddr.IPPort,netip.AddrPort,g' $(git grep -l -F netaddr. ) perl -i -npe 's,netaddr.IP\b,netip.Addr,g' $(git grep -l -F netaddr. ) perl -i -npe 's,netaddr.IPv6Raw\b,netip.AddrFrom16,g' $(git grep -l -F netaddr. ) goimports -w . Then delete some stuff from the net/netaddr shim package which is no longer neeed. Updates #5162 Change-Id: Ia7a86893fe21c7e3ee1ec823e8aba288d4566cd8 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	6a396731eb	all: use various net/netip parse funcs directly ... Mechanical change with perl+goimports. Changed {Must,}Parse{IP,IPPrefix,IPPort} to their netip variants, then goimports -d . Finally, removed the net/netaddr wrappers, to prevent future use. Updates #5162 Change-Id: I59c0e38b5fbca5a935d701645789cddf3d7863ad Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	7eaf5e509f	net/netaddr: start migrating to net/netip via new netaddr adapter package ... Updates #5162 Change-Id: Id7bdec303b25471f69d542f8ce43805328d56c12 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Aaron Klotz	1cae618b03	net/dns: add Windows group policy notifications to the NRPT rule manager ... As discussed in previous PRs, we can register for notifications when group policies are updated and act accordingly. This patch changes nrptRuleDatabase to receive notifications that group policy has changed and automatically move our NRPT rules between the local and group policy subkeys as needed. Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
Melanie Warrick	f17873e0f4	net/dns: handle D-Bus restarts in resolved manager (#5026) ... When dbus restarts it can cause the tailscaled to crash because the nil signal was not handled in resolved.Fixing so the nil signal leads to a connection reset and tailscaled stays connected to systemd when dbus restarted. Fixes #4645 Co-authored-by: James Tucker <james@tailscale.com> Signed-off-by: nyghtowl <warrick@tailscale.com> Co-authored-by: James Tucker <james@tailscale.com>	2 years ago
Andrew Dunham	c7993d2b88	net/dns/resolver: add fuzz/unit test for #2533 (#5018) ... Signed-off-by: Andrew Dunham <andrew@du.nham.ca>	2 years ago
Tom DNetto	d6817d0f22	net/dns/resolver: respond with SERVFAIL if all upstreams fail ... Fixes #4722 Signed-off-by: Tom DNetto <tom@tailscale.com>	2 years ago
Brad Fitzpatrick	aa37aece9c	ipn/ipnlocal, net/dns*, util/cloudenv: add AWS DNS support ... And remove the GCP special-casing from ipn/ipnlocal; do it only in the forwarder for *.internal. Fixes #4980 Fixes #4981 Change-Id: I5c481e96d91f3d51d274a80fbd37c38f16dfa5cb Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Brad Fitzpatrick	88c2afd1e3	ipn/ipnlocal, net/dns*, util/cloudenv: specialize DNS config on Google Cloud ... This does three things: * If you're on GCP, it adds a *.internal DNS split route to the metadata server, so we never break GCP DNS names. This lets people have some Tailscale nodes on GCP and some not (e.g. laptops at home) without having to add a Tailnet-wide *.internal DNS route. If you already have such a route, though, it won't overwrite it. * If the 100.100.100.100 DNS forwarder has nowhere to forward to, it forwards it to the GCP metadata IP, which forwards to 8.8.8.8. This means there are never errNoUpstreams ("upstream nameservers not set") errors on GCP due to e.g. mangled /etc/resolv.conf (GCP default VMs don't have systemd-resolved, so it's likely a DNS supremacy fight) * makes the DNS fallback mechanism use the GCP metadata IP as a fallback before our hosted HTTP-based fallbacks I created a default GCP VM from their web wizard. It has no systemd-resolved. I then made its /etc/resolv.conf be empty and deleted its GCP hostnames in /etc/hosts. I then logged in to a tailnet with no global DNS settings. With this, tailscaled writes /etc/resolv.conf (direct mode, as no systemd-resolved) and sets it to 100.100.100.100, which then has regular DNS via the metadata IP and *.internal DNS via the metadata IP as well. If the tailnet configures explicit DNS servers, those are used instead, except for *.internal. This also adds a new util/cloudenv package based on version/distro where the cloud type is only detected once. We'll likely expand it in the future for other clouds, doing variants of this change for other popular cloud environments. Fixes #4911 RELNOTES=Google Cloud DNS improvements Change-Id: I19f3c2075983669b2b2c0f29a548da8de373c7cf Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	2 years ago
Aaron Klotz	4baf34cf25	net/dns: set appropriate Windows registry values to prevent it from sending DNS changes concerning our interface to AD domain controllers. ... We do this unconditionally inside SetDNS such that the values are always set before we make any other changes to DNS configurations. It should not be harmful for the settings to remain even when other DNS settings are cleared out (since they only affect our network interface). See https://docs.microsoft.com/en-us/troubleshoot/windows-server/networking/configure-dns-dynamic-updates-windows-server-2003 for details about the registry value. Fixes https://github.com/tailscale/tailscale/issues/4829 Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
Aaron Klotz	8cdfd12977	net/dns: update Windows split DNS settings to work alongside other NRPT entries set by group policy. ... When there are group policy entries for the NRPT that do not belong to Tailscale, we recognize that we need to add ourselves to group policy and use that registry key instead of the local one. We also refresh the group policy settings as necessary to ensure that our changes take effect immediately. Fixes https://github.com/tailscale/tailscale/issues/4607 Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
Maisem Ali	80157f3f37	net/dns/resolver: add support for <IPv4>.via-<site-id> ... Currently we only support "via-<site-id>.<IPv4>", however that does not work with Google Chrome which parses `http://via-1.10.0.0.1` as a search string and not as a URL. This commit introduces "<IPv4>.via-<site-id>" (`http://10.0.0.1.via-1`) which is parsed correctly by Chrome. Updates #3616 Signed-off-by: Maisem Ali <maisem@tailscale.com>	2 years ago
Aaron Klotz	b005b79236	net/dns, paths, util/winutil: change net/dns/windowsManager NRPT management to support more than 50 domains. ... AFAICT this isn't documented on MSDN, but based on the issue referenced below, NRPT rules are not working when a rule specifies > 50 domains. This patch modifies our NRPT rule generator to split the list of domains into chunks as necessary, and write a separate rule for each chunk. For compatibility reasons, we continue to use the hard-coded rule ID, but as additional rules are required, we generate new GUIDs. Those GUIDs are stored under the Tailscale registry path so that we know which rules are ours. I made some changes to winutils to add additional helper functions in support of both the code and its test: I added additional registry accessors, and also moved some token accessors from paths to util/winutil. Fixes https://github.com/tailscale/coral/issues/63 Signed-off-by: Aaron Klotz <aaron@tailscale.com>	2 years ago
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
Tom DNetto	5fb8e01a8b	net/dns/resolver: add metric for number of truncated dns packets ... Updates #2067 This should help us determine if more robust control of edns parameters + implementing answer truncation is warranted, given its likely complexity. Signed-off-by: Tom DNetto <tom@tailscale.com>	3 years ago