context.cancelCtx.Done involves a mutex and isn't as cheap as I
previously assumed. Convert the donec method into a struct field and
store the channel value once. Our one magicsock.Conn gets one pointer
larger, but it cuts ~1% of the CPU time of the ReceiveFrom benchmark
and removes a bubble from the --svg output :)
This test serves two purposes:
+ check that Write() returns an error if the tstun has been
closed.
+ ensure that the close-related code in tstun is exercised in
a test case. We were getting spurious code coverage adds/drops
based on timing of when the test case finished.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
22507adf54 stopped relying on
our fork of wireguard-go's UpdateDst callback.
As a result, we can unwind that code,
and the extra return value of ReceiveIPv{4,6}.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
TwoDevicePing is explicitly testing the behavior of the legacy codepath, everything
else is happy to assume that code no longer exists.
Signed-off-by: David Anderson <danderson@tailscale.com>
Previously, this benchmark relied on behavior of the legacy
receive codepath, which I changed in 22507adf. With this
change, the benchmark instead relies on the new active discovery
path.
Signed-off-by: David Anderson <danderson@tailscale.com>
This prevents us from continuing to do unnecessary work
(including logging) after the connection has closed.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This adds a new IP Protocol type, TSMP on protocol number 99 for
sending inter-tailscale messages over WireGuard, currently just for
why a peer rejects TCP SYNs (ACL rejection, shields up, and in the
future: nothing listening, something listening on that port but wrong
interface, etc)
Updates #1094
Updates tailscale/corp#1185
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Commit 68ddf1 removed code that reads
`SOFTWARE\Tailscale IPN\SearchList` registry value. But the commit
left code that writes that value.
So now this package writes and never reads the value.
Remove the code to stop pointless work.
Updates #853
Signed-off-by: Alex Brainman <alex.brainman@gmail.com>
This eliminates a dependency on wgcfg.Endpoint,
as part of the effort to eliminate our wireguard-go fork.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This makes connectivity between ancient and new tailscale nodes slightly
worse in some cases, but only in cases where the ancient version would
likely have failed to get connectivity anyway.
Signed-off-by: David Anderson <danderson@tailscale.com>
This is what every other DNS resolver I could find does, so tsdns
should do it to. This also helps avoid weird error messages about
non-existent records being unimplemented, and thus fixes#848.
Signed-off-by: Smitty <me@smitop.com>
In sendDiscoMessage there is a check of whether the connection is
closed, which is not being reliably exercised by other tests.
This shows up in code coverage reports, the lines of code in
sendDiscoMessage are alternately added and subtracted from
code coverage.
Add a test to specifically exercise and verify this code path.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
In derpWriteChanOfAddr when we call derphttp.NewRegionClient(),
there is a check of whether the connection is already errored and
if so it returns before grabbing the lock. The lock might already
be held and would be a deadlock.
This corner case is not being reliably exercised by other tests.
This shows up in code coverage reports, the lines of code in
derpWriteChanOfAddr are alternately added and subtracted from
code coverage.
Add a test to specifically exercise this code path, and verify that
it doesn't deadlock.
This is the best tradeoff I could come up with:
+ the moment code calls Err() to check if there is an error, we
grab the lock to make sure it would deadlock if it tries to grab
the lock itself.
+ if a new call to Err() is added in this code path, only the
first one will be covered and the rest will not be tested.
+ this test doesn't verify whether code is checking for Err() in
the right place, which ideally I guess it would.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
netaddr.IP no longer allocates, so don't need a cache or all its associated
code/complexity.
This totally removes groupcache/lru from the deps.
Also go mod tidy.
* wengine/netstack: bump gvisor to latest version
Signed-off-by: Naman Sood <naman@tailscale.com>
* update dependencies
Signed-off-by: Naman Sood <naman@tailscale.com>
* Don't change hardcoded IP
Signed-off-by: Naman Sood <naman@tailscale.com>
Not usefully functional yet (mostly a proof of concept), but getting
it submitted for some work @namansood is going to do atop this.
Updates #707
Updates #634
Updates #48
Updates #835
* show DNS name over hostname, removing domain's common MagicDNS suffix.
only show hostname if there's no DNS name.
but still show shared devices' MagicDNS FQDN.
* remove nerdy low-level details by default: endpoints, DERP relay,
public key. They're available in JSON mode still for those who need
them.
* only show endpoint or DERP relay when it's active with the goal of
making debugging easier. (so it's easier for users to understand
what's happening) The asterisks are gone.
* remove Tx/Rx numbers by default for idle peers; only show them when
there's traffic.
* include peers' owner login names
* add CLI option to not show peers (matching --self=true, --peers= also
defaults to true)
* sort by DNS/host name, not public key
* reorder columns
The log lines that wireguard-go prints as it starts
and stops its worker routines are mostly noise.
They also happen after other work is completed,
which causes failures in some of the log testing packages.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This appears to have been the intent of the previous code,
but in practice, it only returned A records.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
To be honest I'm not fond of Golden Bytes tests like this, but
not so much as to want to rewrite the whole test. The DNS byte
format is essentially immutable at this point, the encoded bytes
aren't going to change. The rest of the test assumptions about
hostnames might, but we can fix that when it comes.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
eccc167 introduced closeHandle which opened the handle,
but never closed it.
Windows handles should be closed.
Updates #921
Signed-off-by: Alex Brainman <alex.brainman@gmail.com>
Previously the client had heuristics to calculate which DNS search domains
to set, based on the peers' names. Unfortunately that prevented us from
doing some things we wanted to do server-side related to node sharing.
So, bump MapRequest.Version to 9 to signal that the client only uses the
explicitly configured DNS search domains and doesn't augment it with its own
list.
Updates tailscale/corp#1026
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This is a replacement for the key-related parts
of the wireguard-go wgcfg package.
This is almost a straight copy/paste from the wgcfg package.
I have slightly changed some of the exported functions and types
to avoid stutter, added and tweaked some comments,
and removed some now-unused code.
To avoid having wireguard-go depend on this new package,
wgcfg will keep its key types.
We translate into and out of those types at the last minute.
These few remaining uses will be eliminated alongside
the rest of the wgcfg package.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The windows key timeout is longer than the wgengine watchdog timeout,
which means we never reach the timeout, instead the process exits.
Reduce the timeout so if we do hit it, at least the process continues.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
On Win10, there's a hardcoded GUID and this works.
On Win7, this GUID changes and we need to ask the tun for its
LUID and convert that from the GUID.
This commit uses the computed GUID that is placed in InterfaceName.
Diagnosed by Jason Donnenfeld. (Thanks!)
Lazy wg configuration now triggers if a peer has only endpoint
addresses (/32 for IPv4, /128 for IPv6). Subnet routers still
trigger eager configuration to avoid the need for a CIDR match
in the hot packet path.
Signed-off-by: David Anderson <danderson@tailscale.com>
The previous code used a lot of whole-function variables and shared
behavior that only triggered based on prior action from a single codepath.
Instead of that, move the small amounts of "shared" code into each switch
case.
Signed-off-by: David Anderson <danderson@tailscale.com>
Before, tailscaled would log every 10 seconds when the periodic noteRecvActivity
call happens. This is noisy, but worse it's misleading, because the message
suggests that the disco code is starting a lazy config run for a missing peer,
whereas in fact it's just an internal piece of keepalive logic.
With this change, we still log when going from 0->1 tunnel for the peer, but
not every 10s thereafter.
Signed-off-by: David Anderson <danderson@tailscale.com>
While the code was correct, I broke it during a refactoring and
tests didn't detect it. This fixes that glitch.
Signed-off-by: David Anderson <danderson@tailscale.com>
Doesn't materially affect benchmarks, but shrinks match6 by 30 instructions
and halves memory loads.
Part of #19.
Signed-off-by: David Anderson <danderson@tailscale.com>
Part of #19.
name old time/op new time/op delta
Filter/icmp4-8 32.2ns ± 3% 32.5ns ± 2% ~ (p=0.524 n=10+8)
Filter/icmp6-8 49.7ns ± 6% 43.1ns ± 4% -13.12% (p=0.000 n=9+10)
Signed-off-by: David Anderson <danderson@tailscale.com>
The packet filter still rejects all IPv6, but decodes enough from v6
packets to do something smarter in a followup.
name time/op
Decode/tcp4-8 28.8ns ± 2%
Decode/tcp6-8 20.6ns ± 1%
Decode/udp4-8 28.2ns ± 1%
Decode/udp6-8 20.0ns ± 6%
Decode/icmp4-8 21.7ns ± 2%
Decode/icmp6-8 14.1ns ± 2%
Decode/unknown-8 9.43ns ± 2%
Signed-off-by: David Anderson <danderson@tailscale.com>
In tests, we force binding to localhost to avoid OS firewall warning
dialogs.
But for IPv6, we were trying (and failing) to bind to 127.0.0.1.
You'd think we'd just say "localhost", but that's apparently ill
defined. See
https://tools.ietf.org/html/draft-ietf-dnsop-let-localhost-be-localhost
and golang/go#22826. (It's bitten me in the past, but I can't
remember specific bugs.)
So use "::1" explicitly for "udp6", which makes the test quieter.
The goal is to move some of the shenanigans we have elsewhere into the filter
package, so that all the weird things to do with poking at the filter is in
a single place, behind clean APIs.
Signed-off-by: David Anderson <danderson@tailscale.com>
We still use the packet.* alloc-free types in the data path, but
the compilation from netaddr to packet happens within the filter
package.
Signed-off-by: David Anderson <danderson@tailscale.com>
os.IsNotExist doesn't unwrap errors. errors.Is does.
The ioutil.ReadFile ones happened to be fine but I changed them so
we're consistent with the rule: if the error comes from os, you can
use os.IsNotExist, but from any other package, use errors.Is.
(errors.Is always would also work, but not worth updating all the code)
The motivation here was that we were logging about failure to migrate
legacy relay node prefs file on startup, even though the code tried
to avoid that.
See golang/go#41122
Amazingly, there doesn't seem to be a documented way of updating network
configuration programmatically in a way that Windows takes notice of.
The naturopathic remedy for this is to invoke ipconfig /registerdns, which
does a variety of harmless things and also invokes the private API that
tells windows to notice new adapter settings. This makes our DNS config
changes stick within a few seconds of us setting them.
If we're invoking a shell command anyway, why futz with the registry at
all? Because netsh has no command for changing the DNS suffix list, and
its commands for setting resolvers requires parsing its output and
keeping track of which server is in what index. Amazingly, twiddling
the registry directly is the less painful option.
Fixes#853.
Signed-off-by: David Anderson <danderson@tailscale.com>
Updating the Windows firewall is usually reasonably fast, but
sometimes blocks for 20 seconds, 4 minutes, etc. Not sure why.
Until we understand that's happening, configure it in the background
without blocking the normal control flow.
Updates #785
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The RusagePrefixLog is rarely useful, hasn't been useful in a long
time, is rarely the measurement we need, and is pretty spammy (and
syscall-heavy). Disable it by default. We can enable it when we're
debugging memory.
At startup the client doesn't yet have the DERP map so can't do STUN
queries against DERP servers, so it only knows it local interface
addresses, not its STUN-mapped addresses.
We were reporting the interface-local addresses to control, getting
the DERP map, and then immediately reporting the full set of
updates. That was an extra HTTP request to control, but worse: it was
an extra broadcast from control out to all the peers in the network.
Now, skip the initial update if there are no stun results and we don't
have a DERP map.
More work remains optimizing start-up requests/map updates, but this
is a start.
Updates tailscale/corp#557
There was a bug with the lazy wireguard config code where, if the
minimum set of peers to tell wireguard didn't change, we skipped
calling userspaceEngine.updateActivityMapsLocked which updated
the various data structures that matched incoming traffic to later
reconfigure the minimum config.
That meant if an idle peer restarted and changed discovery keys, we
skipped updating our maps of disco keys/IPs that would caused us to
lazily inflate the config for that peer later if/when it did send
traffic.
Use golang.zx2c4.com/wireguard/windows/tunnel/winipcfg
instead of github.com/tailscale/winipcfg-go package.
Updates #760
Signed-off-by: Alex Brainman <alex.brainman@gmail.com>
Due to a copy/paste-o, we were monitoring address changes twice, and
not monitoring route changes at all.
Verified with 'tailscale debug --monitor' that this actually works now (while
running 'route add 10.3.0.0 mask 255.255.0.0 10.0.0.1' and 'route delete (same)'
back and forth in cmd.exe)
In practice route changes are accompanied by address changes and this
doesn't fix any known issues. I just noticed this while reading this
code again. But at least the code does what it was trying to do now.
This function is only called in fake mode, which won't do anything more
with the packet after we respond to it anyway, so dropping it in the
prefilter is not necessary. And it's kinda semantically wrong: we did
not reject it, so telling the upper layer that it was rejected produces
an ugly error message.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
At some point faketun got implemented as a loopback (put a packet in
from wireguard, the same packet goes back to wireguard) which is not
useful. It's supposed to be an interface that just sinks all packets,
and then wgengine adds *only* and ICMP Echo responder as a layer on
top.
This caused extremely odd bugs on darwin, where the special case that
reinjects packets from local->local was filling the loopback channel
and creating an infinite loop (which became jammed since the reader and
writer were in the same goroutine).
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
If no interfaces are up, calm down and stop spamming so much. It was
noticed as especially bad on Windows, but probably was bad
everywhere. I just have the best network conditions testing on a
Windows VM.
Updates #604
Gracefully skips touching the v6 NAT table on systems that don't have
it, and doesn't configure IPv6 at all if IPv6 is globally disabled.
Signed-off-by: David Anderson <danderson@tailscale.com>
When the network link changes, existing UDP sockets fail immediately
and permanently on macOS.
The forwarder set up a single UDP conn and never changed it.
As a result, any time there was a network link change,
all forwarded DNS queries failed.
To fix this, create a new connection when send requests
fail because of network unreachability.
This change is darwin-only, although extended it to other platforms
should be straightforward.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
While we're here, parseQuery into a plain function.
This is helpful for fuzzing. (Which I did a bit of. Didn't find anything.)
And clean up a few minor things.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Part of unforking our winipcfg-go and using upstream (#760), move our
additions into our repo. (We might upstream them later if upstream has
interest)
Originally these were:
@apenwarr: "Add ifc.SyncAddresses() and SyncRoutes()."
609dcf2df5
@bradfitz: "winipcfg: make Interface.AddRoutes do as much as possible, return combined error"
e9f93d53f3
@bradfitz: "prevent unnecessary Interface.SyncAddresses work; normalize IPNets in deltaNets"
decb9ee8e1
Might fix it. I've spent too much time failing to reproduce the issue. This doesn't
seem to make it worse, though (it still runs for me), so I'll include this and
see if it helps others while I still work on a reliable way to reproduce it.
Updates tailscale/corp#474
Otherwise when PAC server is down, we log, and each log entry is a new
HTTP request (from logtail) and a new GetProxyForURL call, which again
logs, non-stop. This is also nicer to the WinHTTP service.
Then also hook up link change notifications to the cache to reset it
if there's a chance the network might work sooner.
This change is to restore /etc/resolv.conf after tailscale down is called. This is done by setting the dns.Manager before errors occur. Error collection is also added.
Fixes#723
