Running hex.Encode(b, b) is a bad idea.
The first byte of input will overwrite the first two bytes of output.
Subsequent bytes have no impact on the output.
Not related to today's IPv6 bug, but...wh::ps.
This caused us to spuriously ignore some wireguard config updates.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Calculate whether the packet is injected directly,
rather than via an else branch.
Unify the exit paths. It is easier here than duplicating them.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Every TUN Read went through several multi-case selects.
We know from past experience with wireguard-go that these are slow
and cause scheduler churn.
The selects served two purposes: they separated errors from data and
gracefully handled shutdown. The first is fairly easy to replace by sending
errors and data over a single channel. The second, less so.
We considered a few approaches: Intricate webs of channels,
global condition variables. They all get ugly fast.
Instead, let's embrace the ugly and handle shutdown ungracefully.
It's horrible, but the horror is simple and localized.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The implementation of the preview function has changed since the
API was documented, update the document to match.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
We can't access b.netMap without holding b.mu.
We already grabbed it earlier in the function with the lock held.
Introduced in Nov 2020 in 7ea809897d.
Discovered during stress testing.
Apparently it's a pretty rare?
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This puts nix build logs on the filesystem so that we can debug them
later. This also disables nixos unstable until
https://github.com/NixOS/nixpkgs/issues/128783 is fixed.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
For instance, ephemeral nodes with only IPv6 addresses can now
SOCKS5-dial out to names like "foo" and resolve foo's IPv6 address
rather than foo's IPv4 address and get a "no route"
(*tcpip.ErrNoRoute) error from netstack's dialer.
Per https://github.com/tailscale/tailscale/issues/2268#issuecomment-870027626
which is only part of the isuse.
Updates #2268
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We also have to make a one-off change to /etc/wsl.conf to stop every
invocation of wsl.exe clobbering the /etc/resolv.conf. This appears to
be a safe change to make permanently, as even though the resolv.conf is
constantly clobbered, it is always the same stable internal IP that is
set as a nameserver. (I believe the resolv.conf clobbering predates the
MS stub resolver.)
Tested on WSL2, should work for WSL1 too.
Fixes#775
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This is preliminary work for using the directManager as
part of a wslManager on windows, where in addition to configuring
windows we'll use wsl.exe to edit the linux file system and modify the
system resolv.conf.
The pinholeFS is a little funky, but it's designed to work through
simple unix tools via wsl.exe without invoking bash. I would not have
thought it would stand on its own like this, but it turns out it's
useful for writing a test for the directManager.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
After allowing for custom DERP maps, it's convenient to be able to see their latency in
netcheck. This adds a query to the local tailscaled for the current DERPMap.
Updates #1264
Signed-off-by: julianknodt <julianknodt@gmail.com>
Turns out we never reliably log the control plane URL a client connects
to. Do it here, and include the server public key, which might
inadvertently tell us something interesting some day.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This is an experiment to see how often this test would fail if we run it
on every commit. This depends on #2145 to fix a flaky part of the test.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Okay, so, at a high level testing NixOS is a lot different than
other distros due to NixOS' determinism. Normally NixOS wants packages to
be defined in either an overlay, a custom packageOverrides or even
yolo-inline as a part of the system configuration. This is going to have
us take a different approach compared to other distributions. The overall
plan here is as following:
1. make the binaries as normal
2. template in their paths as raw strings to the nixos system module
3. run `nixos-generators -f qcow -o $CACHE_DIR/tailscale/nixos/version -c generated-config.nix`
4. pass that to the steps that make the virtual machine
It doesn't really make sense for us to use a premade virtual machine image
for this as that will make it harder to deterministically create the image.
Nix commands generate a lot of output, so their output is hidden behind the
`-verbose-nix-output` flag.
This unfortunately makes this test suite have a hard dependency on
Nix/NixOS, however the test suite has only ever been run on NixOS (and I
am not sure if it runs on other distros at all), so this probably isn't too
big of an issue.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
This has been bothering me for a while, but everytime I run format from the root directory
it also formats this file. I didn't want to add it to my other PRs but it's annoying to have to
revert it every time.
Signed-off-by: julianknodt <julianknodt@gmail.com>
Move derpmap.Prod to a static JSON file (go:generate'd) instead,
to make its role explicit. And add a TODO about making dnsfallback
use an update-over-time DERP map file instead of a baked-in one.
Updates #1264
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Previously this test would reach out to the public DERP servers in order
to help machines connect with eachother. This is not ideal given our
plans to run these tests completely disconnected from the internet. This
patch introduces an in-process DERP server running on its own randomly
assigned HTTP port.
Updates #1988
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Occasionally the test framework would fail with a timeout due to a
virtual machine not phoning home in time. This seems to be happen
whenever qemu can't bind the VNC or SSH ports for a virtual machine.
This was fixed by taking the following actions:
1. Don't listen on VNC unless the `-use-vnc` flag is passed, this
removes the need to listen on VNC at all in most cases. The option to
use VNC is still left in for debugging virtual machines, but removing
this makes it easier to deal with (VNC uses this odd system of
"displays" that are mapped to ports above 5900, and qemu doesn't
offer a decent way to use a normal port number, so we just disable
VNC by default as a compromise).
2. Use a (hopefully) inactive port for SSH. In an ideal world I'd just
have the VM's SSH port be exposed via a Unix socket, however the QEMU
documentation doesn't really say if you can do this or not. While I
do more research, this stopgap will have to make do.
3. Strictly tie more VM resource lifetimes to the tests themselves.
Previously the disk image layers for virtual machines were only
cleaned up at the end of the test and existed in the parent
test-scoped temporary folder. This can make your tmpfs run out of
space, which is not ideal. This should minimize the use of temporary
storage as much as I know how to.
4. Strictly tie the qemu process lifetime to the lifetime of the test
using testing.T#Cleanup. Previously it used a defer statement to
clean up the qemu process, however if the tests timed out this defer
was not run. This left around an orphaned qemu process that had to be
killed manually. This change ensures that all qemu processes exit
when their relevant tests finish.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Fix regression from 19c3e6cc9e
which made the locking coarser.
Found while debugging #2245, which ended up looking like a tswin/Windows
issue where Crawshaw had blocked cmd.exe's output.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This uses a debug envvar to optionally disable filter logging rate
limits by setting the environment variable
TS_DEBUG_FILTER_RATE_LIMIT_LOGS to "all", and if it matches,
the code will effectively disable the limits on the log rate by
setting the limit to 1 millisecond. This should make sure that all
filter logs will be captured.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
This change (subject to some limitations) looks for the EDNS OPT record
in queries and responses, clamping the size field to fit within our DNS
receive buffer. If the size field is smaller than the DNS receive buffer
then it is left unchanged.
I think we will eventually need to transition to fully processing the
DNS queries to handle all situations, but this should cover the most
common case.
Mostly fixes#2066
Signed-off-by: Adrian Dewhurst <adrian@tailscale.com>
This adds a flag to the DERP server which specifies to verify clients through a local
tailscaled. It is opt-in, so should not affect existing clients, and is mainly intended for
users who want to run their own DERP servers. It assumes there is a local tailscaled running and
will attempt to hit it for peer status information.
Updates #1264
Signed-off-by: julianknodt <julianknodt@gmail.com>
Unused so far, but eventually we'll want this for SOCKS5 UDP binds (we
currently only do TCP with SOCKS5), and also for #2102 for forwarding
MagicDNS upstream to Tailscale IPs over netstack.
Updates #2102
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Windows 8.1 incorrectly handles search paths on an interface with no
associated resolver, so we have to provide a full primary DNS config
rather than use Windows 8.1's nascent-but-present NRPT functionality.
Fixes#2237.
Signed-off-by: David Anderson <danderson@tailscale.com>
This adds a flag to derp maps which specifies that default Tailscale DERP servers should not be
used. If true and there are entries in this map, it indicates that the entries in this map
should take precedent and not hit any of tailscale's DERP servers.
This change is backwards compatible, as the default behavior should be false.
Updates #1264
Signed-off-by: julianknodt <julianknodt@gmail.com>
In order to clone DERPMaps, it was necessary to extend the cloner so that it supports
nested pointers inside of maps which are also cloneable. This also adds cloning for DERPRegions
and DERPNodes because they are on DERPMap's maps.
Signed-off-by: julianknodt <julianknodt@gmail.com>
Josh Bleecher Snyder
Denton Gentry
Brad Fitzpatrick
Christine Dodrill
David Crawshaw
Maisem Ali
julianknodt
Adrian Dewhurst
David Anderson