Commit Graph

240 Commits (059b1d10bb75c868b3c7122b08350c4c904ff12b)

Author SHA1 Message Date
Dmytro Shynkevych 059b1d10bb
wgengine/packet: refactor and expose UDP header marshaling (#408)
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
5 years ago
David Anderson 5a32f8e181 wgengine/router: also accept exit code 254 from `ip rule del`.
iproute2 3.16.0-2 from Debian Jessie (oldoldstable) doesn't return
exit code 2 when deleting a non-existent IP rule.

Fixes #434

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 08a38f21c9 wgengine/router: don't filter subnet routing in netfilter.
We have a filter in tailscaled itself now, which is more robust
against weird network topologies (such as the one Docker creates).

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Dmytro Shynkevych 73c40c77b0
filter: prevent escape of QDecode to the heap (#417)
Performance impact:

name              old time/op  new time/op  delta
Filter/tcp_in-4   70.7ns ± 1%  30.9ns ± 1%  -56.30%  (p=0.008 n=5+5)
Filter/tcp_out-4  58.6ns ± 0%  19.4ns ± 0%  -66.87%  (p=0.000 n=5+4)
Filter/udp_in-4   96.8ns ± 2%  55.5ns ± 0%  -42.64%  (p=0.016 n=5+4)
Filter/udp_out-4   120ns ± 1%    79ns ± 1%  -33.87%  (p=0.008 n=5+5)

Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
5 years ago
Brad Fitzpatrick 722673f307 Update go4.org/mem, adjust to revised API. 5 years ago
Brad Fitzpatrick 9e5d79e2f1 wgengine/magicsock: drop a bytes.Buffer sync.Pool, use logger.ArgWriter instead 5 years ago
Brad Fitzpatrick becce82246 net/netns, misc tests: remove TestOnlySkipPrivilegedOps, argv checks
The netns UID check is sufficient for now. We can do something else
later if/when needed.
5 years ago
Avery Pennarun e7ae6a2e06 net/netns, wgengine/router: support Linux machines that don't have 'ip rule'.
We'll use SO_BINDTODEVICE instead of fancy policy routing. This has
some limitations: for example, we will route all traffic through the
interface that has the main "default" (0.0.0.0/0) route, so machines
that have multiple physical interfaces might have to go through DERP to
get to some peers. But machines with multiple physical interfaces are
very likely to have policy routing (ip rule) support anyway.

So far, the only OS I know of that needs this feature is ChromeOS
(crostini). Fixes #245.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun e46238a2af wgengine: separately dedupe wireguard configs and router configs.
Otherwise iOS/macOS will reconfigure their routing every time anything
minor changes in the netmap (in particular, endpoints and DERP homes),
which is way too often.

Some users reported "network reconfigured" errors from Chrome when this
happens.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun f0b6ba78e8 wgengine: don't pass nil router.Config objects.
These are hard for swift to decode in the iOS app.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
David Anderson 5114df415e net/netns: set the bypass socket mark on linux.
This allows tailscaled's own traffic to bypass Tailscale-managed routes,
so that things like tailscale-provided default routes don't break
tailscaled itself.

Progress on #144.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick db2a216561 wgengine/magicsock: don't log on UDP send errors if address family known missing
Fixes #376
5 years ago
David Crawshaw cf5d25e15b wgengine: ensure pingers are gone before returning from Close
We canceled the pingers in Close, but didn't wait around for their
goroutines to be cleaned up. This caused the ipn/e2e_test to catch
pingers in its resource leak check.

This commit introduces an object, but also simplifies the semantics
around the pinger's cancel functions. They no longer need to be called
while holding the mutex.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick 9e3ad4f79f net/netns: add package for start of network namespace support
And plumb in netcheck STUN packets.

TODO: derphttp, logs, control.

Updates #144

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick a428656280 wgengine/magicsock: don't report v4 localhost addresses on IPv6-only systems
Updates #376
5 years ago
David Anderson fff062b461 wgengine/router: make runner.go linux-only for now.
Otherwise, staticcheck complains that these functions are unused
and unexported on macOS.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Avery Pennarun f69003fd46 router_linux: work around terrible bugs in old iptables-compat versions.
Specifically, this sequence:
	iptables -N ts-forward
	iptables -A ts-forward -m mark --mark 0x10000 -j ACCEPT
	iptables -A FORWARD -j ts-forward
doesn't work on Debian-9-using-nftables, but this sequence:
	iptables -N ts-forward
	iptables -A FORWARD -j ts-forward
	iptables -A ts-forward -m mark --mark 0x10000 -j ACCEPT
does work.

I'm sure the reason why is totally fascinating, but it's an old version
of iptables and the bug doesn't seem to exist on modern nftables, so
let's refactor our code to add rules in the always-safe order and
pretend this never happened.

Fixes #401.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 9ff51909a3 router_linux: fix behaviour when switching --netfilter-mode.
On startup, and when switching into =off and =nodivert, we were
deleting netfilter rules even if we weren't the ones that added them.

In order to avoid interfering with rules added by the sysadmin, we have
to be sure to delete rules only in the case that we added them in the
first place.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun a496cdc943 router_linux: remove need for iptables.ListChains().
Instead of retrieving the list of chains, or the list of rules in a
chain, just try deleting the ones we don't want and then adding the
ones we do want. An error in flushing/deleting still means the rule
doesn't exist anymore, so there was no need to check for it first.

This avoids the need to parse iptables output, which avoids the need to
ever call iptables -S, which fixes #403, among other things. It's also
much more future proof in case the iptables command line changes.

Unfortunately the iptables go module doesn't properly pass the iptables
command exit code back up when doing .Delete(), so we can't correctly
check the exit code there. (exit code 1 really means the rule didn't
exist, rather than some other weird problem).

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 8a6bd21baf router_linux: extract process runner routines into runner.go.
These will probably be useful across platforms. They're not really
Linux-specific at all.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 34c30eaea0 router_linux: use only baseline 'ip rule' features that exist in old kernels.
This removes the use of suppress_ifgroup and fwmark "x/y" notation,
which are, among other things, not available in busybox and centos6.

We also use the return codes from the 'ip' program instead of trying to
parse its output.

I also had to remove the previous hack that routed all of 100.64.0.0/10
by default, because that would add the /10 route into the 'main' route
table instead of the new table 88, which is no good. It was a terrible
hack anyway; if we wanted to capture that route, we should have
captured it explicitly as a subnet route, not as part of the addr. Note
however that this change affects all platforms, so hopefully there
won't be any surprises elsewhere.

Fixes #405
Updates #320, #144

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 30e5c19214 magicsock: work around race condition initializing .Regions[].
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Dmytro Shynkevych 737124ef70 tstun: tolerate zero reads
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
5 years ago
Brad Fitzpatrick b0c10fa610 stun, netcheck: move under net 5 years ago
Brad Fitzpatrick 43ded2b581 wgengine/packet: add some tests, more docs, minor Go style, performance changes 5 years ago
Brad Fitzpatrick e6b84f2159 all: make client use server-provided DERP map, add DERP region support
Instead of hard-coding the DERP map (except for cmd/tailscale netcheck
for now), get it from the control server at runtime.

And make the DERP map support multiple nodes per region with clients
picking the first one that's available. (The server will balance the
order presented to clients for load balancing)

This deletes the stunner package, merging it into the netcheck package
instead, to minimize all the config hooks that would've been
required.

Also fix some test flakes & races.

Fixes #387 (Don't hard-code the DERP map)
Updates #388 (Add DERP region support)
Fixes #399 (wgengine: flaky tests)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Anderson e8b3a5e7a1 wgengine/filter: implement a destination IP pre-filter.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 7fb33123d3 wgengine/router: warn about another variation of busybox's `ip`.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Dmytro Shynkevych 635f7b99f1 wgengine: pass tun.NativeDevice to router
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
5 years ago
David Anderson 9c914dc7dd wgengine/router: stop using -m comment.
The comment module is compiled out on several embedded systems (and
also gentoo, because netfilter can't go brrrr with comments holding it
back). Attempting to use comments results in a confusing error, and a
non-functional firewall.

Additionally, make the legacy rule cleanup non-fatal, because we *do*
have to probe for the existence of these -m comment rules, and doing
so will error out on these systems.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 3e27b3c33c wgengine/router: more comments.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 0fe262f093 ipn: plumb NetfilterMode all the way out to the CLI.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson c67c8913c3 wgengine/router: add a test for linux router state transitions.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 292606a975 wgengine/router: support multiple levels of netfilter involvement.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick e6d0c92b1d wgengine/magicsock: clean up earlier fix a bit
Move WaitReady from fc88e34f42 into the
test code, and keep the derp-reading goroutine named for debugging.
5 years ago
Avery Pennarun d53e8fc0da router_darwin_support: we can build this on every platform.
Our new build scripts try to build ipn-go-bridge on more than just
linux and darwin, so let's enable this file so it can be successful on
every platform.
5 years ago
Avery Pennarun fc88e34f42 wgengine/magicsock/tests: wait for home DERP connection before sending packets.
This fixes an elusive test flake. Fixes #161.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 4f128745d8 magicsock/test: oops, fix a data race in nested-test logf hack.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 42a0e0c601 wgengine/magicsock/tests: call tstest.ResourceCheck for each test.
This didn't catch anything yet, but it's good practice for detecting
goroutine leaks that we might not find otherwise.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Avery Pennarun 08acb502e5 Add tstest.PanicOnLog(), and fix various problems detected by this.
If a test calls log.Printf, 'go test' horrifyingly rearranges the
output to no longer be in chronological order, which makes debugging
virtually impossible. Let's stop that from happening by making
log.Printf panic if called from any module, no matter how deep, during
tests.

This required us to change the default error handler in at least one
http.Server, as well as plumbing a bunch of logf functions around,
especially in magicsock and wgengine, but also in logtail and backoff.

To add insult to injury, 'go test' also rearranges the output when a
parent test has multiple sub-tests (all the sub-test's t.Logf is always
printed after all the parent tests t.Logf), so we need to screw around
with a special Logf that can point at the "current" t (current_t.Logf)
in some places. Probably our entire way of using subtests is wrong,
since 'go test' would probably like to run them all in parallel if you
called t.Parallel(), but it definitely can't because the're all
manipulating the shared state created by the parent test. They should
probably all be separate toplevel tests instead, with common
setup/teardown logic. But that's a job for another time.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Dmytro Shynkevych 33b2f30cea
wgengine: wrap tun.Device to support filtering and packet injection (#358)
Right now, filtering and packet injection in wgengine depend
on a patch to wireguard-go that probably isn't suitable for upstreaming.

This need not be the case: wireguard-go/tun.Device is an interface.
For example, faketun.go implements it to mock a TUN device for testing.

This patch implements the same interface to provide filtering
and packet injection at the tunnel device level,
at which point the wireguard-go patch should no longer be necessary.

This patch has the following performance impact on i7-7500U @ 2.70GHz,
tested in the following namespace configuration:
┌────────────────┐    ┌─────────────────────────────────┐     ┌────────────────┐
│      $ns1      │    │               $ns0              │     │      $ns2      │
│    client0     │    │      tailcontrol, logcatcher    │     │     client1    │
│  ┌─────┐       │    │  ┌──────┐         ┌──────┐      │     │  ┌─────┐       │
│  │vethc│───────┼────┼──│vethrc│         │vethrs│──────┼─────┼──│veths│       │
│  ├─────┴─────┐ │    │  ├──────┴────┐    ├──────┴────┐ │     │  ├─────┴─────┐ │
│  │10.0.0.2/24│ │    │  │10.0.0.1/24│    │10.0.1.1/24│ │     │  │10.0.1.2/24│ │
│  └───────────┘ │    │  └───────────┘    └───────────┘ │     │  └───────────┘ │
└────────────────┘    └─────────────────────────────────┘     └────────────────┘
Before:
---------------------------------------------------
| TCP send               | UDP send               |
|------------------------|------------------------|
| 557.0 (±8.5) Mbits/sec | 3.03 (±0.02) Gbits/sec |
---------------------------------------------------
After:
---------------------------------------------------
| TCP send               | UDP send               |
|------------------------|------------------------|
| 544.8 (±1.6) Mbits/sec | 3.13 (±0.02) Gbits/sec |
---------------------------------------------------
The impact on receive performance is similar.

Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
5 years ago
David Anderson 9ccbcda612 wgengine/router: rename config.Settings to config.Config, make pointer.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 72cae5504c wgengine: generate and plumb router.Settings in from ipn.
This saves a layer of translation, and saves us having to
pass in extra bits and pieces of the netmap and prefs to
wgengine. Now it gets one Wireguard config, and one OS
network stack config.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson cd01bcc395 wgengine/router: allow loopback traffic from our own IP(s).
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson bfdc8175b1 wgengine/router: add a setting to disable SNAT for subnet routes.
Part of #320.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick 8a3e77fc43 ipn, wgengine/filter: remove exported type aliases 5 years ago
David Anderson 21ac65d3da wgengine/router: explicitly detect and complain about busybox's `ip`.
Defensive programming against #368 in environments other than Docker,
e.g. if you try using Tailscale in Alpine Linux directly, sans
container.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 381b94d4d1 wgengine/router: include command output if `ip rule list` fails.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson e83d02ffd1 wgengine: don't double-close tundev on setup error.
Part of #368.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson efc1feedc9 wgengine/router: include more information when iptables ops fail.
The iptables package we use doesn't include command output, so we're
left with guessing what went wrong most of the time. This will at
least narrow things down to which operation failed.

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