Commit Graph

1023 Commits (main)

Author SHA1 Message Date
Will Norris a1d9f65354 ipn,log: add logger for sockstat deltas
Signed-off-by: Will Norris <will@tailscale.com>
Co-authored-by: Melanie Warrick <warrick@tailscale.com>
1 year ago
Maisem Ali 5e8a80b845 all: replace /kb/ links with /s/ equivalents
Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year 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
1 year ago
Mihai Parparita b64d78d58f sockstats: refactor validation to be opt-in
Followup to #7499 to make validation a separate function (
GetWithValidation vs. Get). This way callers that don't need it don't
pay the cost of a syscall per active TCP socket.

Also clears the conn on close, so that we don't double-count the stats.

Also more consistently uses Go doc comments for the exported API of the
sockstats package.

Updates tailscale/corp#9230
Updates #3363

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Mihai Parparita ea81bffdeb sockstats: export as client metrics
Though not fine-grained enough to be useful for detailed analysis, we
might as well export that we gather as client metrics too, since we have
an upload/analysis pipeline for them.

clientmetric.Metric.Add is an atomic add, so it's pretty cheap to also
do per-packet.

Updates tailscale/corp#9230
Updates #3363

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Mihai Parparita 4c2f67a1d0 net/sockstat: fix per-interface statistics not always being available
withSockStats may be called before setLinkMonitor, in which case we
don't have a populated knownInterfaces map. Since we pre-populate the
per-interface counters at creation time, we would end up with an
empty map. To mitigate this, we do an on-demand request for the list of
interfaces.

This would most often happen with the logtail instrumentation, since we
initialize it very early on.

Updates tailscale/corp#9230

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Mihai Parparita f4f8ed98d9 sockstats: add validation for TCP socket stats
We can use the TCP_CONNECTION_INFO getsockopt() on Darwin to get
OS-collected tx/rx bytes for TCP sockets. Since this API is not available
for UDP sockets (or on Linux/Android), we can't rely on it for actual
stats gathering.

However, we can use it to validate the stats that we collect ourselves
using read/write hooks, so that we can be more confident in them. We
do need additional hooks from the Go standard library (added in
tailscale/go#59) to be able to collect them.

Updates tailscale/corp#9230
Updates #3363

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year 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>
1 year 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>
1 year ago
David Crawshaw 96a555fc5a net/socks5: add password auth support
Conforms to RFC 1929.

To support Java HTTP clients via libtailscale, who offer no other
reliable hooks into their sockets.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
1 year ago
Andrew Dunham f6cd24499b net/portmapper: relax source port check for UPnP responses
Per a packet capture provided, some gateways will reply to a UPnP
discovery packet with a UDP packet with a source port that does not come
from the UPnP port. Accept these packets with a log message.

Updates #7377

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I5d4d5b2a0275009ed60f15c20b484fe2025d094b
1 year ago
Andrew Dunham 51eb0b2cb7 net/portmapper: send UPnP protocol in upper-case
We were previously sending a lower-case "udp" protocol, whereas other
implementations like miniupnp send an upper-case "UDP" protocol. For
compatibility, use an upper-case protocol instead.

Updates #7377

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I4aed204f94e4d51b7a256d29917af1536cb1b70f
1 year ago
Andrew Dunham d379a25ae4 net/portmapper: don't pick external ports below 1024
Some devices don't let you UPnP portmap a port below 1024, so let's just
avoid that range of ports entirely.

Updates #7377

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ib7603b1c9a019162cdc4fa21744a2cae48bb1d86
1 year ago
Maisem Ali 1a30b2d73f all: use tstest.Replace more
Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Andrew Dunham 2d3ae485e3 net/interfaces: add better test for LikelyHomeRouterIP
Return a mock set of interfaces and a mock gateway during this test and
verify that LikelyHomeRouterIP returns the outcome we expect. Also
verify that we return an error if there are no IPv4 addresses available.

Follow-up to #7447

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I8f06989e7f1f0bebd108861cbff17b820ed2e6e4
1 year ago
Maisem Ali b9ebf7cf14 tstest: add method to Replace values for tests
We have many function pointers that we replace for the duration of test and
restore it on test completion, add method to do that.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Andrew Dunham 12100320d2 net/interfaces: always return an IPv4 LikelyHomeRouterIP
We weren't filtering out IPv6 addresses from this function, so we could
be returning an IPv4 gateway IP and an IPv6 self IP. Per the function
comments, only return IPv4 addresses for the self IP.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: If19a4aadc343fbd4383fc5290befa0eff006799e
1 year ago
Andrew Dunham 73fa7dd7af util/slicesx: add package for generic slice functions, use
Now that we're using rand.Shuffle in a few locations, create a generic
shuffle function and use it instead. While we're at it, move the
interleaveSlices function to the same package for use.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I0b00920e5b3eea846b6cedc30bd34d978a049fd3
1 year ago
Andrew Dunham 3f8e8b04fd cmd/tailscale, cmd/tailscaled: move portmapper debugging into tailscale CLI
The debug flag on tailscaled isn't available in the macOS App Store
build, since we don't have a tailscaled binary; move it to the
'tailscale debug' CLI that is available on all platforms instead,
accessed over LocalAPI.

Updates #7377

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I47bffe4461e036fab577c2e51e173f4003592ff7
1 year ago
Mihai Parparita 3e71e0ef68
net/sockstats: remove explicit dependency on wgengine/monitor
Followup to #7177 to avoid adding extra dependencies to the CLI. We
instead declare an interface for the link monitor.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Andrew Dunham 27575cd52d net/dnsfallback: shuffle returned IPs
This ensures that we're trying multiple returned IPs, since the DERP
servers return the same response to all queries. This should increase
the chances that we eventually reach a working IP.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie8d4fb93df96da910fae49ae71bf3e402b9fdecc
1 year 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>
1 year ago
Mihai Parparita 780c56e119 ipn/ipnlocal: add delegated interface information to /interfaces PeerAPI handler
Exposes the delegated interface data added by #7248 in the debug
endpoint. I would have found it useful when working on that PR, and
it may be handy in the future as well.

Also makes the interfaces table slightly easier to parse by adding
borders to it. To make then nicer-looking, the CSP was relaxed to allow
inline styles.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year 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>
1 year ago
Mihai Parparita fa932fefe7 net/interfaces: redo how we get the default interface on macOS and iOS
With #6566 we added an external mechanism for getting the default
interface, and used it on macOS and iOS (see tailscale/corp#8201).
The goal was to be able to get the default physical interface even when
using an exit node (in which case the routing table would say that the
Tailscale utun* interface is the default).

However, the external mechanism turns out to be unreliable in some
cases, e.g. when multiple cellular interfaces are present/toggled (I
have occasionally gotten my phone into a state where it reports the pdp_ip1
interface as the default, even though it can't actually route traffic).

It was observed that `ifconfig -v` on macOS reports an "effective interface"
for the Tailscale utn* interface, which seems promising. By examining
the ifconfig source code, it turns out that this is done via a
SIOCGIFDELEGATE ioctl syscall. Though this is a private API, it appears
to have been around for a long time (e.g. it's in the 10.13 xnu release
at https://opensource.apple.com/source/xnu/xnu-4570.41.2/bsd/net/if_types.h.auto.html)
and thus is unlikely to go away.

We can thus use this ioctl if the routing table says that a utun*
interface is the default, and go back to the simpler mechanism that
we had before #6566.

Updates #7184
Updates #7188

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Mihai Parparita 21fda7f670 net/routetable: include unknown flags in the routetable doctor output
As part of the work on #7248 I wanted to know all of the flags on the
RouteMessage struct that we get back from macOS. Though it doesn't turn
out to be useful (when using an exit node/Tailscale is the default route,
the flags for the physical interface routes are the same), it still seems
useful from a debugging/comprehensiveness perspective.

Adds additional Darwin flags that were output once I enabled this mode.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Tom DNetto 2ca6dd1f1d wgengine: start logging DISCO frames to pcap stream
Signed-off-by: Tom DNetto <tom@tailscale.com>
1 year ago
Colin Adler 3c107ff301
net/connstats: fix ticker in NewStatistics (#7225)
`:=` was accidentally used, so `maxPeriod` never worked.

Signed-off-by: Colin Adler <colin1adler@gmail.com>
1 year ago
Mihai Parparita 62f4df3257 net/interfaces, net/netns: add node attributes to control default interface getting and binding
With #6566 we started to more aggressively bind to the default interface
on Darwin. We are seeing some reports of the wrong cellular interface
being chosen on iOS. To help with the investigation, this adds to knobs
to control the behavior changes:
- CapabilityDebugDisableAlternateDefaultRouteInterface disables the
  alternate function that we use to get the default interface on macOS
  and iOS (implemented in tailscale/corp#8201). We still log what it
  would have returned so we can see if it gets things wrong.
- CapabilityDebugDisableBindConnToInterface is a bigger hammer that
  disables binding of connections to the default interface altogether.

Updates #7184
Updates #7188

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year ago
Brad Fitzpatrick 2477fc4952 net/netutil: only check Linux sysctls w/ procfs, assume absent means false
Fixes #7217

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Tom DNetto 99b9d7a621 all: implement pcap streaming for datapath debugging
Updates: tailscale/corp#8470

Signed-off-by: Tom DNetto <tom@tailscale.com>
1 year 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>
1 year ago
Mihai Parparita b6908181ff net/tshttpproxy: more directly use Transport proxy CONNECT hooks
GetProxyConnectHeader (golang/go#41048) was upstreamed in Go 1.16 and
OnProxyConnectResponse (golang/go#54299) in Go 1.20, thus we no longer
need to guard their use by the tailscale_go build tag.

Updates #7123

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
1 year 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
1 year ago
Brad Fitzpatrick 03645f0c27 net/{netns,netstat}: use new x/sys/cpu.IsBigEndian
See golang/go#57237

Change-Id: If47ab6de7c1610998a5808e945c4177c561eab45
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Andrew Dunham 2755f3843c health, net/tlsdial: add healthcheck for self-signed cert
When we make a connection to a server, we previously would verify with
the system roots, and then fall back to verifying with our baked-in
Let's Encrypt root if the system root cert verification failed.

We now explicitly check for, and log a health error on, self-signed
certificates. Additionally, we now always verify against our baked-in
Let's Encrypt root certificate and log an error if that isn't
successful. We don't consider this a health failure, since if we ever
change our server certificate issuer in the future older non-updated
versions of Tailscale will no longer be healthy despite being able to
connect.

Updates #3198

Change-Id: I00be5ceb8afee544ee795e3c7a2815476abc4abf
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
1 year ago
Brad Fitzpatrick cf8dd7aa09 all: use Go 1.20's bytes.Clone
Updates #7123
Updates #6257 (more to do in other repos)

Change-Id: I073e2a6d81a5d7fbecc29caddb7e057ff65239d0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year 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>
1 year ago
Maisem Ali 5bba65e978 net/memnet: rename from net/nettest
This is just #cleanup to resolve a TODO

Also add a package doc.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Will Norris 947c14793a all: update tools that manage copyright headers
Update all code generation tools, and those that check for license
headers to use the new standard header.

Also update copyright statement in LICENSE file.

Fixes #6865

Signed-off-by: Will Norris <will@tailscale.com>
1 year 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>
1 year ago
Andrew Dunham 50da265608 net/netns: add post-review comments
Follow-up to #7065 with some comments from Brad's review.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ia1219f4fa25479b2dada38ffe421065b408c5954
1 year ago
Brad Fitzpatrick 2fc8de485c net/netstat: document the Windows netstat code a bit more
And defensively bound allocation.

Updates tailscale/corp#8878

Change-Id: Iaa07479ea2ea28ee1ac3326ab025046d6d785b00
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Aaron Klotz 4a869048bf net/netstat: add nil checks to Windows OSMetadata implementation
The API documentation does claim to output empty strings under certain
conditions, but we're sometimes seeing nil pointers in the wild, not empty
strings.

Fixes https://github.com/tailscale/corp/issues/8878

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
1 year ago
Andrew Dunham 2703d6916f net/netns: add functionality to bind outgoing sockets based on route table
When turned on via environment variable (off by default), this will use
the BSD routing APIs to query what interface index a socket should be
bound to, rather than binding to the default interface in all cases.

Updates #5719
Updates #5940

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ib4c919471f377b7a08cd3413f8e8caacb29fee0b
1 year ago
Andrew Dunham 44d73ce932 ipn/ipnlocal, net/dnscache: allow configuring dnscache logging via capability
This allows users to temporarily enable/disable dnscache logging via a
new node capability, to aid in debugging strange connectivity issues.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I46cf2596a8ae4c1913880a78d0033f8b668edc08
1 year ago
Brad Fitzpatrick d5100e0910 net/connstats: mark TestConcurrent as flaky
Updates #7030

Change-Id: Ic46da5e5690b90b95028a68a3cf967ad86881e28
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year 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>
1 year ago
andig 5f96d6211a Remove redundant type declaration
Signed-off-by: andig <cpuidle@gmx.de>
1 year 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>
1 year ago
Brad Fitzpatrick 6d85a94767 net/{packet,tstun}: fix typo in test helper docs
Change-Id: Ifc1684fe77c7d2585e049e0dfd7340910c47a67a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Brad Fitzpatrick c1a2e2c380 net/{packet,tstun},wgengine/filter: fix unknown IP protocol handling
01b90df2fa added SCTP support before
(with explicit parsing for ports) and
69de3bf7bf tried to add support for
arbitrary IP protocols (as long as the ACL permited a port of "*",
since we might not know how to find ports from an arbitrary IP
protocol, if it even has such a concept). But apparently that latter
commit wasn't tested end-to-end enough. It had a lot of tests, but the
tests made assumptions about layering that either weren't true, or
regressed since 1.20. Notably, it didn't remove the (*Filter).pre
bidirectional filter that dropped all "unknown" protocol packets both
leaving and entering, even if there were explicit protocol matches
allowing them in.

Also, don't map all unknown protocols to 0. Keep their IP protocol
number parsed so it's matchable by later layers. Only reject illegal
things.

Fixes #6423
Updates #2162
Updates #2163

Change-Id: I9659b3ece86f4db51d644f9b34df78821758842c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Jordan Whited 25a0091f69
net/portmapper: relax handling of UPnP resp (#6946)
Gateway devices operating as an HA pair w/VRRP or CARP may send UPnP
replies from static addresses rather than the floating gateway address.
This commit relaxes our source address verification such that we parse
responses from non-gateway IPs, and re-point the UPnP root desc
URL to the gateway IP. This ensures we are still interfacing with the
gateway device (assuming L2 security intact), even though we got a
root desc from a non-gateway address.

This relaxed handling is required for ANY port mapping to work on certain
OPNsense/pfsense distributions using CARP at the time of writing, as
miniupnpd may only listen on the static, non-gateway interface address
for PCP and PMP.

Fixes #5502

Signed-off-by: Jordan Whited <jordan@tailscale.com>
1 year ago
Tom DNetto 2ac5474be1 net/flowtrack,wgengine/filter: refactor Cache to use generics
Signed-off-by: Tom DNetto <tom@tailscale.com>
1 year 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>
1 year ago
James Tucker b2c55e62c8 net/tlsdial,tstest,version: use go command from $PATH
Go now includes the GOROOT bin directory in $PATH while running tests
and generate, so it is no longer necessary to construct a path using
runtime.GOROOT().

Fixes #6689

Signed-off-by: James Tucker <james@tailscale.com>
1 year 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>
1 year ago
andig 14e8afe444 go.mod, etc: bump gvisor
Fixes #6554

Change-Id: Ia04ae37a47b67fa57091c9bfe1d45a1842589aa8
Signed-off-by: andig <cpuidle@gmx.de>
1 year 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>
1 year ago
Aaron Klotz 296f53524c netstat, portlist: update Windows implementation to disambiguate svchost processes
We change our invocations of GetExtendedTcpTable to request additional
information about the "module" responsible for the port. In addition to pid,
this output also includes sufficient metadata to enable Windows to resolve
process names and disambiguate svchost processes.

We store the OS-specific output in an OSMetadata field in netstat.Entry, which
portlist may then use as necessary to actually resolve the process/module name.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
1 year ago
Joe Tsai d9df023e6f
net/connstats: enforce maximum number of connections (#6760)
The Tailscale logging service has a hard limit on the maximum
log message size that can be accepted.
We want to ensure that netlog messages never exceed
this limit otherwise a client cannot transmit logs.

Move the goroutine for periodically dumping netlog messages
from wgengine/netlog to net/connstats.
This allows net/connstats to manage when it dumps messages,
either based on time or by size.

Updates tailscale/corp#8427

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Jordan Whited 55b24009f7
net/tstun: don't return early from a partial tun.Read() (#6745)
Fixes #6730

Signed-off-by: Jordan Whited <jordan@tailscale.com>
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
Jordan Whited ea5ee6f87c
all: update golang.zx2c4.com/wireguard to github.com/tailscale/wireguard-go (#6692)
This is temporary while we work to upstream performance work in
https://github.com/WireGuard/wireguard-go/pull/64. A replace directive
is less ideal as it breaks dependent code without duplication of the
directive.

Signed-off-by: Jordan Whited <jordan@tailscale.com>
2 years ago
Maisem Ali eb1adf629f net/tstun: reuse buffered packet from pool
We would call parsedPacketPool.Get() for all packets received in Read/Write.
This was wasteful and not necessary, fetch a single *packet.Parsed for
all packets.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Jordan Whited 76389d8baf
net/tstun, wgengine/magicsock: enable vectorized I/O on Linux (#6663)
This commit updates the wireguard-go dependency and implements the
necessary changes to the tun.Device and conn.Bind implementations to
support passing vectors of packets in tailscaled. This significantly
improves throughput performance on Linux.

Updates #414

Signed-off-by: Jordan Whited <jordan@tailscale.com>
Signed-off-by: James Tucker <james@tailscale.com>
Co-authored-by: James Tucker <james@tailscale.com>
2 years ago
Brad Fitzpatrick 1598cd0361 net/tsaddr: remove ContainsFunc helpers (they're now in x/exp/slices)
x/exp/slices now has ContainsFunc (golang/go#53983) so we can delete
our versions.

Change-Id: I5157a403bfc1b30e243bf31c8b611da25e995078
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Mihai Parparita 79f3a5d753 net/netns, net/interfaces: explicitly bind sockets to the default interface on all Darwin variants
We were previously only doing this for tailscaled-on-Darwin, but it also
appears to help on iOS. Otherwise, when we rebind magicsock UDP
connections after a cellular -> WiFi interface change they still keep
using cellular one.

To do this correctly when using exit nodes, we need to exclude the
Tailscale interface when getting the default route, otherwise packets
cannot leave the tunnel. There are native macOS/iOS APIs that we can
use to do this, so we allow those clients to override the implementation
of DefaultRouteInterfaceIndex.

Updates #6565, may also help with #5156

Signed-off-by: Mihai Parparita <mihai@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
Joe Tsai 2e5d08ec4f
net/connstats: invert network logging data flow (#6272)
Previously, tstun.Wrapper and magicsock.Conn managed their
own statistics data structure and relied on an external call to
Extract to extract (and reset) the statistics.
This makes it difficult to ensure a maximum size on the statistics
as the caller has no introspection into whether the number
of unique connections is getting too large.

Invert the control flow such that a *connstats.Statistics
is registered with tstun.Wrapper and magicsock.Conn.
Methods on non-nil *connstats.Statistics are called for every packet.
This allows the implementation of connstats.Statistics (in the future)
to better control when it needs to flush to ensure
bounds on maximum sizes.

The value registered into tstun.Wrapper and magicsock.Conn could
be an interface, but that has two performance detriments:

1. Method calls on interface values are more expensive since
they must go through a virtual method dispatch.

2. The implementation would need a sync.Mutex to protect the
statistics value instead of using an atomic.Pointer.

Given that methods on constats.Statistics are called for every packet,
we want reduce the CPU cost on this hot path.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Denton Gentry b8fe89d15f net/portmapper: add test for Huawei router
Updates https://github.com/tailscale/tailscale/issues/6320

Signed-off-by: Denton Gentry <dgentry@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 e9c851b04b ipn/ipnlocal: also accept service IP IPv6 literal in brackets for quad100
The fix in 4fc8538e2 was sufficient for IPv6. Browsers (can?) send the
IPv6 literal, even without a port number, in brackets.

Updates tailscale/corp#7948

Change-Id: I0e429d3de4df8429152c12f251ab140b0c8f6b77
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Maisem Ali 22238d897b all: standardize on PeerAPI
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick fb392e34b5 net/tshttpproxy: don't ignore env-based HTTP proxies after system lookups fail
There was a mechanism in tshttpproxy to note that a Windows proxy
lookup failed and to stop hitting it so often. But that turns out to
fire a lot (no PAC file configured at all results in a proxy lookup),
so after the first proxy lookup, we were enabling the "omg something's
wrong, stop looking up proxies" bit for awhile, which was then also
preventing the normal Go environment-based proxy lookups from working.

This at least fixes environment-based proxies.

Plenty of other Windows-specific proxy work remains (using
WinHttpGetIEProxyConfigForCurrentUser instead of just PAC files,
ignoring certain types of errors, etc), but this should fix
the regression reported in #4811.

Updates #4811

Change-Id: I665e1891897d58e290163bda5ca51a22a017c5f9
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 3114eacbb8 ipn/ipnlocal: don't warn about serve listener failing on IPv6-less machines
Fixes #6303

Change-Id: Ie1ce12938f68dfa0533246bbe3b9d7f3e749a243
Signed-off-by: Brad Fitzpatrick <bradfitz@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
Maisem Ali 8e85227059 cmd/tailscale/cli: [set] handle selectively modifying routes/exit node
Noticed this while debugging something else, we would reset all routes if
either `--advertise-exit-node` or `--advertise-routes` were set. This handles
correctly updating them.

Also added tests.

Signed-off-by: Maisem Ali <maisem@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
Andrew Dunham e85613aa2d net/netcheck: don't use a space in the captive portal challenge
The derpers don't allow whitespace in the challenge.

Change-Id: I93a8b073b846b87854fba127b5c1d80db205f658
Signed-off-by: Andrew Dunham <andrew@tailscale.com>
2 years ago
Andrew Dunham c2d7940ec0 cmd/tailscaled, net/tstun: add build tags to omit BIRD and TAP
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I7a39f4eeeb583b73ecffaf4c5f086a38e3a53e2e
2 years ago
Brad Fitzpatrick 036334e913 net/netcheck: deflake (maybe) magicsock's TestNewConn
Updates #6207

Change-Id: I51d200d0b42b9a1ef799d0abfc8d4bd871c50cf2
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
Brad Fitzpatrick d57cba8655 net/tshttpproxy: add clientmetrics on Windows proxy lookup paths
To collect some data on how widespread this is and whether there's
any correlation between different versions of Windows, etc.

Updates #4811

Change-Id: I003041d0d7e61d2482acd8155c1a4ed413a2c5c4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick f4ff26f577 types/pad32: delete package
Use Go 1.19's new 64-bit alignment ~hidden feature instead.

Fixes #5356

Change-Id: Ifcbcb115875a7da01df3bc29e9e7feadce5bc956
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
Joe Tsai c21a3c4733
types/netlogtype: new package for network logging types (#6092)
The netlog.Message type is useful to depend on from other packages,
but doing so would transitively cause gvisor and other large packages
to be linked in.

Avoid this problem by moving all network logging types to a single package.

We also update staticcheck to take in:

	003d277bcf

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Andrew Dunham 95f3dd1346 net/interfaces: don't dereference null pointer if no destination/netmask
Fixes #6065

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I7159b8cbb8d5f47c0668cf83e59167f182f1defd
2 years ago
Andrew Dunham ba459aeef5 net/interfaces: don't call GetList in List.ForeachInterface
It looks like this was left by mistake in 4a3e2842.

Change-Id: Ie4e3d5842548cd2e8533b3552298fb1ce9ba761a
Signed-off-by: Andrew Dunham <andrew@tailscale.com>
2 years ago
Peter Cai 4597ec1037 net/dnscache: Handle 4-in-6 addresses in DNS responses
On Android, the system resolver can return IPv4 addresses as IPv6-mapped
addresses (i.e. `::ffff:a.b.c.d`). After the switch to `net/netip`
(19008a3), this case is no longer handled and a response like this will
be seen as failure to resolve any IPv4 addresses.

Handle this case by simply calling `Unmap()` on the returned IPs. Fixes #5698.

Signed-off-by: Peter Cai <peter@typeblog.net>
2 years ago
Andrew Dunham 74693793be net/netcheck, tailcfg: track whether OS supports IPv6
We had previously added this to the netcheck report in #5087 but never
copied it into the NetInfo struct. Additionally, add it to log lines so
it's visible to support.

Change-Id: Ib6266f7c6aeb2eb2a28922aeafd950fe1bf5627e
Signed-off-by: Andrew Dunham <andrew@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
Andrew Dunham 223126fe5b cmd/derper, net/netcheck: add challenge/response to generate_204 endpoint
The Lufthansa in-flight wifi generates a synthetic 204 response to the
DERP server's /generate_204 endpoint. This PR adds a basic
challenge/response to the endpoint; something sufficiently complicated
that it's unlikely to be implemented by a captive portal. We can then
check for the expected response to verify whether we're being MITM'd.

Follow-up to #5601

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I94a68c9a16a7be7290200eea6a549b64f02ff48f
2 years ago
Anton Tolchanov d499afac78 net/interfaces: improve default route detection
Instead of treating any interface with a non-ifscope route as a
potential default gateway, now verify that a given route is
actually a default route (0.0.0.0/0 or ::/0).

Fixes #5879

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Anton Tolchanov 9c2ad7086c net/interfaces: deduplicate route table parsing on Darwin and FreeBSD
Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Mihai Parparita 9d04ffc782 net/wsconn: add back custom wrapper for turning a websocket.Conn into a net.Conn
We removed it in #4806 in favor of the built-in functionality from the
nhooyr.io/websocket package. However, it has an issue with deadlines
that has not been fixed yet (see nhooyr/websocket#350). Temporarily
go back to using a custom wrapper (using the fix from our fork) so that
derpers will stop closing connections too aggressively.

Updates #5921

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
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
Brad Fitzpatrick 9a264dac01 net/netcheck: fix crash in checkCaptivePortal
If netcheck happens before there's a derpmap.

This seems to only affect Headscale because it doesn't send a derpmap
as early?

Change-Id: I51e0dfca8e40623e04702bc9cc471770ca20d2c2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Joe Tsai 1b4e4cc1e8
wgengine/netlog: new package for traffic flow logging (#5864)
The Logger type managers a logtail.Logger for extracting
statistics from a tstun.Wrapper.
So long as Shutdown is called, it ensures that logtail
and statistic gathering resources are properly cleared up.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Maisem Ali ecf6cdd830 ssh/tailssh: add TestSSHAuthFlow
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Joe Tsai 84e8f25c21
net/tstun: rename statististics method (#5852)
Rename StatisticsEnable as SetStatisticsEnabled to be consistent
with other similarly named methods.

Rename StatisticsExtract as ExtractStatistics to follow
the convention where methods start with a verb.
It was originally named with Statistics as a prefix so that
statistics related methods would sort well in godoc,
but that property no longer holds.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai dd045a3767
net/flowtrack: add json tags to Tuple (#5849)
By convention, JSON serialization uses camelCase.
Specify such names on the Tuple type.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai a73c423c8a
net/tunstats: add Counts.Add (#5848)
The Counts.Add method merges two Counts together.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 24ebf161e8
net/tstun: instrument Wrapper with statistics gathering (#5847)
If Wrapper.StatisticsEnable is enabled,
then per-connection counters are maintained.
If enabled, Wrapper.StatisticsExtract must be periodically called
otherwise there is unbounded memory growth.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 2934c5114c
net/tunstats: new package to track per-connection counters (#5818)
High-level API:

	type Statistics struct { ... }
	type Counts struct { TxPackets, TxBytes, RxPackets, RxBytes uint64 }
	func (*Statistics) UpdateTx([]byte)
	func (*Statistics) UpdateRx([]byte)
	func (*Statistics) Extract() map[flowtrack.Tuple]Counts

The API accepts a []byte instead of a packet.Parsed so that a future
implementation can directly hash the address and port bytes,
which are contiguous in most IP packets.
This will be useful for a custom concurrent-safe hashmap implementation.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
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
Emmanuel T Odeke f981b1d9da all: fix resource leaks with missing .Close() calls
Fixes #5706

Signed-off-by: Emmanuel T Odeke <emmanuel@orijtech.com>
2 years ago
Andrew Dunham b1867457a6
doctor: add package for running in-depth healthchecks; use in bugreport (#5413)
Change-Id: Iaa4e5b021a545447f319cfe8b3da2bd3e5e5782b
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
James Tucker f7cb535693 net/speedtest: retune to meet iperf on localhost in a VM
- removed some in-flow time calls
- increase buffer size to 2MB to overcome syscall cost
- move relative time computation from record to report time

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
James Tucker 146f51ce76 net/packet: fix filtering of short IPv4 fragments
The fragment offset is an 8 byte offset rather than a byte offset, so
the short packet limit is now in fragment block size in order to compare
with the offset value.

The packet flags are in the first 3 bits of the flags/frags byte, and
so after conversion to a uint16 little endian value they are at the
start, not the end of the value - the mask for extracting "more
fragments" is adjusted to match this byte.

Extremely short fragments less than 80 bytes are dropped, but fragments
over 80 bytes are now accepted.

Fixes #5727

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Andrew Dunham c6162c2a94
net/netcheck: add check for captive portal (#5593)
This doesn't change any behaviour for now, other than maybe running a
full netcheck more often. The intent is to start gathering data on
captive portals, and additionally, seeing this in the 'tailscale
netcheck' command should provide a bit of additional information to
users.

Updates #1634

Change-Id: I6ba08f9c584dc0200619fa97f9fde1a319f25c76
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Denton Gentry 42f1d92ae0 net/netns: implement UseSocketMark for Android.
Build fails on Android:
`../../../../go/pkg/mod/tailscale.com@v1.1.1-0.20220916223019-65c24b6334e9/wgengine/magicsock/magicsock_linux.go:133:12: undefined: netns.UseSocketMark`

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
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
Andrew Dunham cf61070e26
net/dnscache: add better logging to bootstrap DNS path (#5640)
Change-Id: I4cde3a72e06dac18df856a0cfeac10ab7e3a9108
Signed-off-by: Andrew Dunham <andrew@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
David Anderson 7c49db02a2 wgengine/magicsock: don't use BPF receive when SO_MARK doesn't work.
Fixes #5607

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
Brad Fitzpatrick 024257ef5a net/stun: unmap IPv4 addresses in 16 byte STUN replies
Updates #5602

Change-Id: I2276ad2bfb415b9ff52f37444f2a1d74b38543b1
Signed-off-by: Brad Fitzpatrick <bradfitz@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 81bc4992f2 net/netns: add TS_FORCE_LINUX_BIND_TO_DEVICE for Linux
For debugging a macOS-specific magicsock issue. macOS runs in
bind-to-interface mode always. This lets me force Linux into the same
mode as macOS, even if the Linux kernel supports SO_MARK, as it
usually does.

Updates #2331 etc

Change-Id: Iac9e4a7429c1781337e716ffc914443b7aa2869d
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
Andrew Dunham f52a659076
net/dnsfallback: allow setting log function (#5550)
This broke a test in corp that enforces we don't use the log package.

Signed-off-by: Andrew Dunham <andrew@tailscale.com>
2 years ago
Andrew Dunham b8596f2a2f
net/dnsfallback: cache most recent DERP map on disk (#5545)
This is especially helpful as we launch newer DERPs over time, and older
clients have progressively out-of-date static DERP maps baked in. After
this, as long as the client has successfully connected once, it'll cache
the most recent DERP map it knows about.

Resolves an in-code comment from @bradfitz

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Kris Brandow 19008a3023 net/dnscache: use net/netip
Removes usage of net.IP and net.IPAddr where possible from net/dnscache.

Fixes #5282

Signed-off-by: Kris Brandow <kris.brandow@gmail.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
Kris Brandow 9ae1161e85 net/dnscache: fix v4addrs to return only v4 addrs
Update the v4addrs function to filter out IPv6 addresses.

Fixes regression from 8725b14056.

Signed-off-by: Kris Brandow <kris.brandow@gmail.com>
2 years ago
Kris Brandow 8f38afbf8e net/stun: convert to use net/netip.AddrPort
Convert ParseResponse and Response to use netip.AddrPort instead of
net.IP and separate port.

Fixes #5281

Signed-off-by: Kris Brandow <kris.brandow@gmail.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
Andrew Dunham d942a2ff56
net/dnscache: try IPv6 addresses first (#5349)
Signed-off-by: Andrew Dunham <andrew@tailscale.com>

Signed-off-by: Andrew Dunham <andrew@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
Brad Fitzpatrick ec9d13bce5 hostinfo, net/netcheck: use CutPrefix
Updates #5309

Change-Id: I37e594cfd245784bf810c493de68a66d3ff20677
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 18109c63b0 net/socks5: use new Go 1.19 binary.AppendByteOrder.AppendUintX
Updates #4872

Change-Id: I43db63d2ba237324bc1cd87d4261197f14cb1088
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Andrew Dunham f0d6f173c9
net/netcheck: try ICMP if UDP is blocked (#5056)
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Maisem Ali a9f6cd41fd all: use syncs.AtomicValue
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick 4950fe60bd syncs, all: move to using Go's new atomic types instead of ours
Fixes #5185

Change-Id: I850dd532559af78c3895e2924f8237ccc328449d
Signed-off-by: Brad Fitzpatrick <bradfitz@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 5381437664 logtail, net/portmapper, wgengine/magicsock: use fmt.Appendf
Fixes #5206

Change-Id: I490bb92e774ce7c044040537e2cd864fcf1dbe5a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 5f6abcfa6f all: migrate code from netaddr.FromStdAddr to Go 1.18
With caveat https://github.com/golang/go/issues/53607#issuecomment-1203466984
that then requires a new wrapper. But a simpler one at least.

Updates #5162

Change-Id: I0a5265065bfcd7f21e8dd65b2bd74cae90d76090
Signed-off-by: Brad Fitzpatrick <bradfitz@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
Aaron Klotz 4dbdb19c26 net/tshttpproxy: fix incorrect type in Windows implementation, switch to mkwinsyscall, fix memory leak
The definition of winHTTPProxyInfo was using the wrong type (uint16 vs uint32)
for its first field. I fixed that type.

Furthermore, any UTF16 strings returned in that structure must be explicitly
freed. I added code to do this.

Finally, since this is the second time I've seen type safety errors in this code,
I switched the native API calls over to use wrappers generated by mkwinsyscall.
I know that would not have helped prevent the previous two problems, but every
bit helps IMHO.

Updates https://github.com/tailscale/tailscale/issues/4811

Signed-off-by: Aaron Klotz <aaron@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
Maisem Ali 9514ed33d2 go.mod: bump gvisor.dev/gvisor
Pick up https://github.com/google/gvisor/pull/7787

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
David Anderson c1cb3efbba net/netcheck: test for OS IPv6 support as well as connectivity.
This lets us distinguish "no IPv6 because the device's ISP doesn't
offer IPv6" from "IPv6 is unavailable/disabled in the OS".

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
Brad Fitzpatrick 0d52674a84 net/tstun: diagnose /dev/net/tun fd leak, give better failure message
Updates #5029

Change-Id: Ibee5e0c9076fe764eb5d856d5ef8b09f4d0e2921
Signed-off-by: Brad Fitzpatrick <bradfitz@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
Mihai Parparita ec649e707f ipn/ipnlocal: prefer to use one CGNAT route on the Mac
Together with 06aa141632 this minimizes
the number of NEPacketTunnelNetworkSettings updates that we have to do,
and thus avoids Chrome interrupting outstanding requests due to
(perceived) network changes.

Updates #3102

Signed-off-by: Mihai Parparita <mihai@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
Denton Gentry d7f452c0a1 net/portmapper: send discovery packet for IGD specifically.
There appear to be devices out there which send only their
first descriptor in response to a discovery packet for
`ssdp:all`, for example the Sagemcom FAST3890V3 only sends
urn:schemas-wifialliance-org:device:WFADevice:1

Send both ssdp:all and a discovery frame for
InternetGatewayDevice specifically.

Updates https://github.com/tailscale/tailscale/issues/3557

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry 09eaba91ad net/portmap: add a test for Sagemcom FAST3890V3.
Updates https://github.com/tailscale/tailscale/issues/3557

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry b5553c6ad2 net/portmap: run go fmt
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry de4c635e54 net/portmapper: make pcpCodeNotAuthorized log more descriptive
If PCP is present but disabled, turning it on might help
get direct connections.

Signed-off-by: Denton Gentry <dgentry@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
Brad Fitzpatrick 13d0b8e6a4 control/controlclient, net/dnscache: use typed singleflight fork
Change-Id: I12be4c5a91ae3a812fe88d9b2d15526fdbb5a921
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Denton Gentry 1392a93445 socks5: add a simple test
Start up a backend service, put a SOCKS5 server in front
of it, and verify that we can get data from the backend via
SOCKS5.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry 7fffddce8e net/portmapper: enable for iOS
In the 1.27 unstable releases we set the min-version to iOS15,
which means we have 50 MBytes of RAM in the Network Extension.
https://tailscale.com/blog/go-linker/

Include the UPnP/NAT-PMP/PCP portmapper support now that there
is memory for it.

Fixes https://github.com/tailscale/tailscale/issues/2495
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Mihai Parparita edc90ebc61 net/wsconn: remove homegrown wrapper for turning a websocket.Conn into a net.Conn
The one from the nhooyr/websocket package seems to work equally well.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita 27a1ad6a70
wasm: exclude code that's not used on iOS for Wasm too
It has similar size constraints. Saves ~1.9MB from the Wasm build.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita a9f32656f5 control/controlhttp: allow client and server to communicate over WebSockets
We can't do Noise-over-HTTP in Wasm/JS (because we don't have bidirectional
communication), but we should be able to do it over WebSockets. Reuses
derp WebSocket support that allows us to turn a WebSocket connection
into a net.Conn.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@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
Brad Fitzpatrick 1336fb740b wgengine/netstack: make netstack MTU be 1280 also
Updates #3878

Change-Id: I1850085b32c8a40d85607b4ad433622c97d96a8d
Signed-off-by: Brad Fitzpatrick <bradfitz@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>
2 years ago
Mihai Parparita 86069874c9 net/tstun, wgengine: use correct type for counter metrics
We were marking them as gauges, but they are only ever incremented,
thus counter is more appropriate.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Maisem Ali fd99c54e10 tailcfg,all: change structs to []*dnstype.Resolver
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 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>
2 years ago
James Tucker f9e86e64b7 *: use WireGuard where logged, printed or named
Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
James Tucker ae483d3446 wgengine, net/packet, cmd/tailscale: add ICMP echo
Updates tailscale/corp#754

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Tom DNetto 2a0b5c21d2 net/dns/{., resolver}, wgengine: fix goroutine leak on shutdown
Signed-off-by: Tom DNetto <tom@tailscale.com>
2 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>
2 years ago
Tom DNetto 9e77660931 net/tstun,wgengine/{.,netstack}: handle UDP magicDNS traffic in netstack
This change wires netstack with a hook for traffic coming from the host
into the tun, allowing interception and handling of traffic to quad-100.

With this hook wired, magicDNS queries over UDP are now handled within
netstack. The existing logic in wgengine to handle magicDNS remains for now,
but its hook operates after the netstack hook so the netstack implementation
takes precedence. This is done in case we need to support platforms with
netstack longer than expected.

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
Tom DNetto dc71d3559f net/tstun,wgengine: split PreFilterOut into multiple hooks
A subsequent commit implements handling of magicDNS traffic via netstack.
Implementing this requires a hook for traffic originating from the host and
hitting the tun, so we make another hook to support this.

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 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>
2 years ago
Brad Fitzpatrick 6bed781259 all: gofmt all
Well, goimports actually (which adds the normal import grouping order we do)

Change-Id: I0ce1b1c03185f3741aad67c14a7ec91a838de389
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
James Tucker 96fec4b969 net/tshttpproxy: synology: pick proxy by scheme
This updates the fix from #4562 to pick the proxy based on the request
scheme.

Updates #4395, #2605, #4562
Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Maisem Ali eff6a404a6 net/tshttpproxy: use http as the scheme for proxies
Currently we try to use `https://` when we see `https_host`, however
that doesn't work and results in errors like `Received error: fetch
control key: Get "https://controlplane.tailscale.com/key?v=32":
proxyconnect tcp: tls: first record does not look like a TLS handshake`

This indiciates that we are trying to do a HTTPS request to a HTTP
server. Googling suggests that the standard is to use `http` regardless
of `https` or `http` proxy

Updates #4395, #2605

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Maisem Ali 5a1ef1bbb9 net/tsdial: add SystemDial as a wrapper on netns.Dial
The connections returned from SystemDial are automatically closed when
there is a major link change.

Also plumb through the dialer to the noise client so that connections
are auto-reset when moving from cellular to WiFi etc.

Updates #3363

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick c6c752cf64 net/tshttpproxy: fix typo
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 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>
2 years ago
Brad Fitzpatrick e97209c6bf net/dns: add tailscaled-on-macOS DNS OSConfigurator
This populates DNS suffixes ("ts.net", etc) in /etc/resolver/* files
to point to 100.100.100.100 so MagicDNS works.

It also sets search domains.

Updates #4276

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Tom DNetto 78fededaa5 net/dns/resolver: support magic resolution of via-<siteid>.<ip4> domains
Updates #3616

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
James Tucker 700bd37730 tshttpproxy: support synology proxy configuration
Fixes #4395
Fixes #2605

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Tom DNetto df26c63793 net/dns/resolver, net/tsaddr: fix reverse lookups in 4to6 IP range
Fixes #4439

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
Brad Fitzpatrick d413850bd7 cmd/tailscale: add "debug via" subcommand to do CIDR math for via ranges
$ tailscale debug via 0xb 10.2.0.0/16
fd7a:115c:a1e0:b1a:0🅱️a02:0/112
$ tailscale debug via fd7a:115c:a1e0:b1a:0🅱️a02:0/112
site 11 (0xb), 10.2.0.0/16

Previously: 3ae701f0eb

This adds a little debug tool to do CIDR math to make converting between
those ranges easier for now.

Updates #3616

Change-Id: I98302e95d17765bfaced3ecbb71cbd43e84bff46
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Tom DNetto c8f4dfc8c0 derp/derphttp,net/netcheck: improve netcheck behavior under MITM proxies
In cases where tailscale is operating behind a MITM proxy, we need to consider
that a lot more of the internals of our HTTP requests are visible and may be
used as part of authorization checks. As such, we need to 'behave' as closely
as possible to ideal.

 - Some proxies do authorization or consistency checks based the on Host header
   or HTTP URI, instead of just the IP/hostname/SNI. As such, we need to
   construct a `*http.Request` with a valid URI everytime HTTP is going to be
   used on the wire, even if its over TLS.
   Aside from the singular instance in net/netcheck, I couldn't find anywhere
   else a http.Request was constructed incorrectly.

 - Some proxies may deny requests, typically by returning a 403 status code. We
   should not consider these requests as a valid latency check, so netcheck
   semantics have been updated to consider >299 status codes as a failed probe.

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 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>
2 years ago
Brad Fitzpatrick e3a4952527 net/dns/resolver: count errors when racing DNS queries, fail earlier
If all N queries failed, we waited until context timeout (in 5
seconds) to return.

This makes (*forwarder).forward fail fast when the network's
unavailable.

Change-Id: Ibbb3efea7ed34acd3f3b29b5fee00ba8c7492569
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick d9efbd97cb net/dns: remove an unused function
Change-Id: I7c920c76223ffac37954ef2a18754afc52177598
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick ecea6cb994 net/dns/resolver: make DoH dialer use existing dnscache happy eyeball dialer
Simplify the ability to reason about the DoH dialing code by reusing the
dnscache's dialer we already have.

Also, reduce the scope of the "ip" variable we don't want to close over.

This necessarily adds a new field to dnscache.Resolver:
SingleHostStaticResult, for when the caller already knows the IPs to be
returned.

Change-Id: I9f2aef7926f649137a5a3e63eebad6a3fffa48c0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick f4f76eb275 net/dnsfallback: update from 'go generate'
Change-Id: I93e0e6d9a4a471953c1ffef07f32605c5724aed8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
phirework 52d32c94d8
net/dns/publicdns: add missing call to sync.Once.Do (#4410)
Signed-off-by: Jenny Zhang <jz@tailscale.com>
2 years ago
phirework 83c734a6e0
net/dns, util/publicdns: extract public DNS mapping into own package (#4405)
This extracts DOH mapping of known public DNS providers in
forwarder.go into its own package, to be consumed by other repos

Signed-off-by: Jenny Zhang <jz@tailscale.com>
2 years ago
Brad Fitzpatrick a49d8d5200 Revert ".github/workflows: work around golang/go#51629"
This reverts commit 2a412ac9ee.

Updates #4194

Change-Id: I0098b66b71d20bea301ca79058c1cdd201237dd0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 3ae701f0eb net/tsaddr, wgengine/netstack: add IPv6 range that forwards to site-relative IPv4
This defines a new magic IPv6 prefix, fd7a:115c:a1e0:b1a::/64, a
subset of our existing /48, where the final 32 bits are an IPv4
address, and the middle 32 bits are a user-chosen "site ID". (which
must currently be 0000:00xx; the top 3 bytes must be zero for now)

e.g., I can say my home LAN's "site ID" is "0000:00bb" and then
advertise its 10.2.0.0/16 IPv4 range via IPv6, like:

    tailscale up --advertise-routes=fd7a:115c:a1e0:b1a::bb:10.2.0.0/112

(112 being /128 minuse the /96 v6 prefix length)

Then people in my tailnet can:

     $ curl '[fd7a:115c:a1e0:b1a::bb:10.2.0.230]'
     <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ....

Updates #3616, etc

RELNOTE=initial support for TS IPv6 addresses to route v4 "via" specific nodes

Change-Id: I9b49b6ad10410a24b5866b9fbc69d3cae1f600ef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 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>
2 years ago
Tom 6be7931eb4
net/dns/resolver: return symbolic PTR records for TS service IPs (#4361)
Fixes #1233

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

Co-authored-by: Tom DNetto <tom@tailscale.com>
2 years ago
Maisem Ali 309ddef852
net/netutil: add CheckIPForwardingLinux (#4301)
Combine the code between `LocalBackend.CheckIPForwarding` and
`controlclient.ipForwardingBroken`.

Fixes #4300

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick e4d8d5e78b net/packet, wgengine/netstack: remove workaround for old gvisor ECN bug
Fixes #2642

Change-Id: Ic02251d24a4109679645d1c8336e0f961d0cce13
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 753f1bfad4 cmd/tailscale: write fewer known_hosts, resolve ssh host to FQDN early
Updates #3802

Change-Id: Ic44fa2e6661a9c046e725c04fa6b8213d3d4d2b2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Maisem Ali b2f269d5b7 net/dnsfallback: do not attempt lookups of IPs.
Currently if the passed in host is an IP, Lookup still attempts to
resolve it with a dns server. This makes it just return the IP directly.

Updates tailscale/corp#4475

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Maisem Ali b45bb577a0 net/dnscache: do not call LookupIPFallback if the context was canceled.
When the context is canceled, dc.dialOne returns an error from line 345.
This causes the defer on line 312 to try to resolve the host again, which
triggers a dns lookup of "127.0.0.1" from derp.

Updates tailscale/corp#4475

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick b647977b33 net/netutil: move some net utils from control/controlhttp to netutil
In prep for reuse elsewhere.

Change-Id: I1b804edf76ac66b9108e6f434e77eab7a7472d69
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
James Tucker 445c04c938
wgengine: inject packetbuffers rather than bytes (#4220)
Plumb the outbound injection path to allow passing netstack
PacketBuffers down to the tun Read, where they are decref'd to enable
buffer re-use. This removes one packet alloc & copy, and reduces GC
pressure by pooling outbound injected packets.

Fixes #2741
Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Brad Fitzpatrick f2041c9088 all: use strings.Cut even more
Change-Id: I943ce72c6f339589235bddbe10d07799c4e37979
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Aaron Klotz 6e91f872af net/tshttpproxy: ensure we pass the correct flags to WinHttpOpen on Win7 and Win8.0
The best flag to use on Win7 and Win8.0 is deprecated in Win8.1, so we resolve
the flag depending on OS version info.

Fixes https://github.com/tailscale/tailscale/issues/4201

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
David Anderson 2a412ac9ee .github/workflows: work around golang/go#51629
Incidentally, simplify the go generate CI workflow, by
marking the dnsfallback update non-hermetic (so CI will
skip it) rather than manually filter it out of `go list`.

Updates #4194

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
Josh Bleecher Snyder 0868329936 all: use any instead of interface{}
My favorite part of generics.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Brad Fitzpatrick 61ee72940c all: use Go 1.18's strings.Cut
More remain.

Change-Id: I6ec562cc1f687600758deae1c9d7dbd0d04004cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Josh Bleecher Snyder 0ef74f37a5 net/dns/resolver: remove closure allocation explanation
As of Go 1.18, the register ABI list includes arm64, amd64,
ppc64, and ppc64le. This is a large enough percentage of the
architectures that it's not worth explaining.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Brad Fitzpatrick 61cdcf4082 net/interfaces: add FreeBSD default route lookup (portmapping, etc)
Updates #4101 (probably fixes)

Change-Id: I2b75ee3ced276fb7b211f17c382621cf1ef882fa
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Maisem Ali 2fb087891b net/socks5: always close client connections after serving
Customer reported an issue where the connections were not closing, and
would instead just stay open. This commit makes it so that we close out
the connection regardless of what error we see. I've verified locally
that it fixes the issue, we should add a test for this.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick b493ef5b71 net/tsaddr: add func ContainsExitRoutes
Change-Id: I772441a406083e2fe0f9374b2b23d89aac18928f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 55095df644 net/interfaces: get Linux default route from netlink as fallback
If it's in a non-standard table, as it is on Unifi UDM Pro, apparently.

Updates #4038 (probably fixes, but don't have hardware to verify)

Change-Id: I2cb9a098d8bb07d1a97a6045b686aca31763a937
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Dmytro Shynkevych d9a7205be5 net/tstun: set link speed to SPEED_UNKNOWN
Fixes #3933.

Signed-off-by: Dmytro Shynkevych <dm.shynk@gmail.com>
2 years ago
Brad Fitzpatrick 7d897229d9 net/dns: ignore permission errors on Synology DSM7 for now
Updates #4017

Change-Id: Ia7fd4df47588c010dea8e63d88f397cc8eb748e5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick bb94561c96 net/netutil: fix regression where peerapi would get closed after 1st req
I introduced a bug in 8fe503057d when unifying oneConnListener
implementations.

The NewOneConnListenerFrom API was easy to misuse (its Close method
closes the underlying Listener), and we did (via http.Serve, which
closes the listener after use, which meant we were close the peerapi's
listener, even though we only wanted its Addr)

Instead, combine those two constructors into one and pass in the Addr
explicitly, without delegating through to any Listener.

Change-Id: I061d7e5f842e0cada416e7b2dd62100d4f987125
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
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>
2 years ago
Brad Fitzpatrick 8d6cf14456 net/dnscache: don't do bootstrap DNS lookup after most failed dials
If we've already connected to a certain name's IP in the past, don't
assume the problem was DNS related. That just puts unnecessarily load
on our bootstrap DNS servers during regular restarts of Tailscale
infrastructure components.

Also, if we do do a bootstrap DNS lookup and it gives the same IP(s)
that we already tried, don't try them again.

Change-Id: I743e8991a7f957381b8e4c1508b8e9d0df1782fe
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 903988b392 net/dnscache: refactor from func-y closure-y state to types & methods
No behavior changes (intended, at least).

This is in prep for future changes to this package, which would get
too complicated in the current style.

Change-Id: Ic260f8e34ae2f64f34819d4a56e38bee8d8ac5ce
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 8267ea0f80 net/tstun: remove TODO that's done
This TODO was both added and fixed in 506c727e3.

As I recall, I wasn't originally going to do it because it seemed
annoying, so I wrote the TODO, but then I felt bad about it and just
did it, but forgot to remove the TODO.

Change-Id: I8f3514809ad69b447c62bfeb0a703678c1aec9a3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 8fe503057d net/netutil: unify two oneConnListeners into a new package
I was about to add a third copy, so unify them now instead.

Change-Id: I3b93896aa1249b1250a6b1df4829d57717f2311a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
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>
2 years ago
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>
2 years ago
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>
2 years ago
Brad Fitzpatrick 2a67beaacf net/interfaces: bound Linux /proc/net/route parsing
tailscaled was using 100% CPU on a machine with ~1M lines, 100MB+
of /proc/net/route data.

Two problems: in likelyHomeRouterIPLinux, we didn't stop reading the
file once we found the default route (which is on the first non-header
line when present). Which meant it was finding the answer and then
parsing 100MB over 1M lines unnecessarily. Second was that if the
default route isn't present, it'd read to the end of the file looking
for it. If it's not in the first 1,000 lines, it ain't coming, or at
least isn't worth having. (it's only used for discovering a potential
UPnP/PMP/PCP server, which is very unlikely to be present in the
environment of a machine with a ton of routes)

Change-Id: I2c4a291ab7f26aedc13885d79237b8f05c2fd8e4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
Brad Fitzpatrick 1af26222b6 go.mod: bump netstack, switch to upstream netstack
Now that Go 1.17 has module graph pruning
(https://go.dev/doc/go1.17#go-command), we should be able to use
upstream netstack without breaking our private repo's build
that then depends on the tailscale.com Go module.

This is that experiment.

Updates #1518 (the original bug to break out netstack to own module)
Updates #2642 (this updates netstack, but doesn't remove workaround)

Change-Id: I27a252c74a517053462e5250db09f379de8ac8ff
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
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>
2 years ago
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>
2 years ago
Brad Fitzpatrick c64af5e676 wgengine/netstack: clear TCP ECN bits before giving to gvisor
Updates #2642

Change-Id: Ic219442a2656dd9dc99ae1dd91e907fd3d924987
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 390490e7b1 net/packet: fix typo in comment
Change-Id: Ia666609fde18db44bf38d4e656f490fc372ac3b6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
David Anderson 463b3e8f62 net/dnscache: use tls.Conn.HandshakeContext.
Go 1.17 added a HandshakeContext func to take care of timeouts during
TLS handshaking, so switch from our homegrown goroutine implementation
to the standard way.

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
David Anderson a9da6b73a8 net/dnscache: don't cancel the TLS context before writing to the result channel.
Cancelling the context makes the timeout goroutine race with the write that
reports a successful TLS handshake, so you can end up with a successful TLS
handshake that mysteriously reports that it timed out after ~0s in flight.

The context is always canceled and cleaned up as the function exits, which
happens mere microseconds later, so just let function exit clean up and
thereby avoid races.

Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago
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>
2 years ago
Brad Fitzpatrick 51bc9a6d9d net/netns: remove a useless probe of the "ip" command
We stopped using it in 1.18.

Change-Id: If5adf1d99275286a89e2a05f0bce5193d9f6e5e3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
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>
2 years ago
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>
2 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>
2 years ago
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>
2 years ago
Brad Fitzpatrick 7d9b1de3aa netcheck,portmapper,magicsock: ignore some UDP write errors on Linux
Treat UDP send EPERM errors as a lost UDP packet, not something super
fatal. That's just the Linux firewall preventing it from going out.

And add a leaf package net/neterror for that (and future) policy that
all three packages can share, with tests.

Updates #3619

Change-Id: Ibdb838c43ee9efe70f4f25f7fc7fdf4607ba9c1d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 2c94e3c4ad wgengine/magicsock: don't unconditionally close DERP connections on rebind
Only if the source address isn't on the currently active interface or
a ping of the DERP server fails.

Updates #3619

Change-Id: I6bf06503cff4d781f518b437c8744ac29577acc8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 04c2c5bd80 net/interfaces: define DefaultRouteInterface and State.DefaultRouteInterface
It was pretty ill-defined before and mostly for logging. But I wanted
to start depending on it, so define what it is and make Windows match
the other operating systems, without losing the log output we had
before. (and add tests for that)

Change-Id: I0fbbba1cfc67a265d09dd6cb738b73f0f6005247
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
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>
2 years ago
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>
3 years ago
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>
3 years ago
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>
3 years ago
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>
3 years ago
Brad Fitzpatrick c7052154d5 net/dns/resolver: fix the subject in a func comment
Change-Id: I519268c20dbd2c2da92da565839d3c1c84612dcc
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
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>
3 years ago
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>
3 years ago
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>
3 years ago
Brad Fitzpatrick 39ffa16853 net/dnscache, net/tsdial: add DNS caching to tsdial UserDial
This is enough to handle the DNS queries as generated by Go's
net package (which our HTTP/SOCKS client uses), and the responses
generated by the ExitDNS DoH server.

This isn't yet suitable for putting on 100.100.100.100 where a number
of different DNS clients would hit it, as this doesn't yet do
EDNS0. It might work, but it's untested and likely incomplete.

Likewise, this doesn't handle anything about truncation, as the
exchanges are entirely in memory between Go or DoH. That would also
need to be handled later, if/when it's hooked up to 100.100.100.100.

Updates #3507

Change-Id: I1736b0ad31eea85ea853b310c52c5e6bf65c6e2a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 21741e111b net/packet: add ICMP6Header, like ICMP4Header
So we can generate IPv6 ping replies.

Change-Id: I79a9a38d8aa242e5dfca4cd15dfaffaea6cb1aee
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick affc4530a2 net/packet: don't make IP6Header.marshalPseudo assume UDP
It will be used for ICMPv6 next, so pass in the proto.

Also, use the ipproto constants rather than hardcoding the mysterious
number.

Change-Id: I57b68bdd2d39fff75f82affe955aff9245de246b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 485bcdc951 net/packet: fix doc copy/paste-o
Change-Id: I0aca490b3ccb0c124192afb362a10b19a15a3e2b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 9c5c9d0a50 ipn/ipnlocal, net/tsdial: make SOCKS/HTTP dials use ExitDNS
And simplify, unexport some tsdial/netstack stuff in the the process.

Fixes #3475

Change-Id: I186a5a5cbd8958e25c075b4676f7f6e70f3ff76e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick adc5997592 net/tsdial: give netstack a Dialer, start refactoring name resolution
This starts to refactor tsdial.Dialer's name resolution to have
different stages: in-memory MagicDNS vs system resolution. A future
change will plug in ExitDNS resolution.

This also plumbs a Dialer into netstack and unexports the dnsMap
internals.

And it removes some of the async AddNetworkMapCallback usage and
replaces it with synchronous updates of the Dialer's netmap
from LocalBackend, since the LocalBackend has the Dialer too.

Updates #3475

Change-Id: Idcb7b1169878c74f0522f5151031ccbc49fe4cb4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8775c646be net/tsdial: make dialing to peerapi work in netstack mode
With this, I'm able to send a Taildrop file (using "tailscale file cp")
from a Linux machine running --tun=userspace-networking.

Updates #2179

Change-Id: I4e7a4fb0fbda393e4fb483adb06b74054a02cfd0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick ad3d6e31f0 net/tsdial: move macOS/iOS peerapi sockopt logic from LocalBackend
Change-Id: I812cae027c40c70cdc701427b1a1850cd9bcd60c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c7fb26acdb net/tsdial: also plumb TUN name and monitor into tsdial.Dialer
In prep for moving stuff out of LocalBackend.

Change-Id: I9725aa9c3ebc7275f8c40e040b326483c0340127
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
Josh Bleecher Snyder 2075c39fd7 net/portmapper: deflake TestPCPIntegration
Logging in goroutines after the test completed
caused data races and panics. Prevent that.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick d5405c66b7 net/tsdial: start of new package to unify all outbound dialing complexity
For now this just deletes the net/socks5/tssocks implementation (and
the DNSMap stuff from wgengine/netstack) and moves it into net/tsdial.

Then initialize a Dialer early in tailscaled, currently only use for the
outbound and SOCKS5 proxies. It will be plumbed more later. Notably, it
needs to get down into the DNS forwarder for exit node DNS forwading
in netstack mode. But it will also absorb all the peerapi setsockopt
and netns Dial and tlsdial complexity too.

Updates #1713

Change-Id: Ibc6d56ae21a22655b2fa1002d8fc3f2b2ae8b6df
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
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>
3 years ago
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>
3 years ago
David Anderson 124363e0ca net/dns: detect and decode UTF-16 from wsl.exe earlier.
Fixes #3170

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Josh Bleecher Snyder e16cb523aa net/nettest: deflake TestPipeTimeout
The block-write and block-read tests are both flaky,
because each assumes it can get a normal read/write
completed within 10ms. This isn’t always true.

We can’t increase the timeouts, because that slows down the test.
However, we don’t need to issue a regular read/write for this test.
The immediately preceding tests already test this code,
using a far more generous timeout.

Remove the extraneous read/write.

This drops the failure rate from 1 per 20,000 to undetectable
on my machine.

While we’re here, fix a typo in a debug print statement.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder a8cc519c70 net/portmapper: improve handling of UPnP parse errors
Without the continue, we might overwrite our current meta
with a zero meta.

Log the error, so that we can check for anything unexpected.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder fddf43f3d1 net/portmapper: fill out PCP/PMP client metrics
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 9787ec6f4a net/portmapper: add UPnP client metrics
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago