We don't use the port that wireguard-go passes to us (via magicsock.connBind.Open).
We ignore it entirely and use the port we selected.
When we tell wireguard-go that we're changing the listen_port,
it calls connBind.Close and then connBind.Open.
And in the meantime, it stops calling the receive functions,
which means that we stop receiving and processing UDP and DERP packets.
And that is Very Bad.
That was never a problem prior to b3ceca1dd7,
because we passed the SkipBindUpdate flag to our wireguard-go fork,
which told wireguard-go not to re-bind on listen_port changes.
That commit eliminated the SkipBindUpdate flag.
We could write a bunch of code to work around the gap.
We could add background readers that process UDP and DERP packets when wireguard-go isn't.
But it's simpler to never create the conditions in which wireguard-go rebinds.
The other scenario in which wireguard-go re-binds is device.Down.
Conveniently, we never call device.Down. We go from device.Up to device.Close,
and the latter only when we're shutting down a magicsock.Conn completely.
Rubber-ducked-by: Avery Pennarun <apenwarr@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The shim implements both network and DNS configurators,
and feeds both into a single callback that receives
both configs.
Signed-off-by: David Anderson <danderson@tailscale.com>
Upstream wireguard-go has changed its receive model.
NewDevice now accepts a conn.Bind interface.
The conn.Bind is stateless; magicsock.Conns are stateful.
To work around this, we add a connBind type that supports
cheap teardown and bring-up, backed by a Conn.
The new conn.Bind allows us to specify a set of receive functions,
rather than having to shoehorn everything into ReceiveIPv4 and ReceiveIPv6.
This lets us plumbing DERP messages directly into wireguard-go,
instead of having to mux them via ReceiveIPv4.
One consequence of the new conn.Bind layer is that
closing the wireguard-go device is now indistinguishable
from the routine bring-up and tear-down normally experienced
by a conn.Bind. We thus have to explicitly close the magicsock.Conn
when the close the wireguard-go device.
One downside of this change is that we are reliant on wireguard-go
to call receiveDERP to process DERP messages. This is fine for now,
but is perhaps something we should fix in the future.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The code is not obviously better or worse, but this makes the little warning
triangle in my editor go away, and the distraction removal is worth it.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Google Cloud Run does not implement NETLINK_ROUTE RTMGRP.
If initialization of the netlink socket or group membership
fails, fall back to a polling implementation.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
The resolver still only supports a single upstream config, and
ipn/wgengine still have to split up the DNS config, but this moves
closer to unifying the DNS configs.
As a handy side-effect of the refactor, IPv6 MagicDNS records exist
now.
Signed-off-by: David Anderson <danderson@tailscale.com>
The call to appendEndpoint updates cpeer.Endpoints.
Then it is overwritten in the next line.
The only errors from appendEndpoint occur when
the host/port pair is malformed, but that cannot happen.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
It can end up executing an a new goroutine,
at which point instead of immediately stopping test execution, it hangs.
Since this is unexpected anyway, panic instead.
As a bonus, it makes call sites nicer and removes a kludge comment.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
So we have a documented & tested way to check whether we're in
netstack mode. To be used by future commits.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For discovery when an explicit hostname/IP is known. We'll still
also send it via control for finding peers by a list.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
"Fake" doesn't mean a lot any more, given that many components
of the engine can be faked out, including in valid production
configurations like userspace-networking.
Signed-off-by: David Anderson <danderson@tailscale.com>
This makes setup more explicit in prod codepaths, without
requiring a bunch of arguments or helpers for tests and
userspace mode.
Signed-off-by: David Anderson <danderson@tailscale.com>
This works around the close syscall being slow.
We can revert this if we find a fix or if Apple makes close fast again.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The tstun packagen contains both constructors for generic tun
Devices, and a wrapper that provides additional functionality.
Signed-off-by: David Anderson <danderson@tailscale.com>
Now callers (wgengine/monitor) don't need to mutate the state to remove
boring interfaces before calling State.Equal. Instead, the methods
to remove boring interfaces from the State are removed, as is
the reflect-using Equal method itself, and in their place is
a new EqualFiltered method that takes a func predicate to match
interfaces to compare.
And then the FilterInteresting predicate is added for use
with EqualFiltered to do the job that that wgengine/monitor
previously wanted.
Now wgengine/monitor can keep the full interface state around,
including the "boring" interfaces, which we'll need for peerapi on
macOS/iOS to bind to the interface index of the utunN device.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
e.g.
$ tailscale ping 1.1.1.1
exit node found but not enabled
$ tailscale ping 10.2.200.2
node "tsbfvlan2" found, but not using its 10.2.200.0/24 route
$ sudo tailscale up --accept-routes
$ tailscale ping 10.2.200.2
pong from tsbfvlan2 (100.124.196.94) via 10.2.200.34:41641 in 1ms
$ tailscale ping mon.ts.tailscale.com
pong from monitoring (100.88.178.64) via DERP(sfo) in 83ms
pong from monitoring (100.88.178.64) via DERP(sfo) in 21ms
pong from monitoring (100.88.178.64) via [2604:a880:4:d1::37:d001]:41641 in 22ms
This necessarily moves code up from magicsock to wgengine, so we can
look at the actual wireguard config.
Fixes#1564
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Add proto to flowtrack.Tuple.
Add types/ipproto leaf package to break a cycle.
Server-side ACL work remains.
Updates #1516
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This reverts the revert commit 84aba349d9.
And changes us to use inet.af/netstack.
Updates #1518
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Should help iOS battery life on NEProvider.wake/skip events
with useless route updates that shouldn't cause re-STUNs.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
gVisor fixed their google/gvisor#1446 so we can include gVisor mode
on 32-bit machines.
A few minor upstream API changes, as normal.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
No server support yet, but we want Tailscale 1.6 clients to be able to respond
to them when the server can do it.
Updates #1310
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
There was a logical race where Conn.Rebind could acquire the
RebindingUDPConn mutex, close the connection, fail to rebind, release
the mutex, and then because the mutex was no longer held, ReceiveIPv4
wouldn't retry reads that failed with net.ErrClosed, letting that
error back to wireguard-go, which would then stop running that receive
IP goroutine.
Instead, keep the RebindingUDPConn mutex held for the entirety of the
replacement in all cases.
Updates tailscale/corp#1289
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
interfaces.State.String tries to print a concise summary of the
network state, removing any interfaces that don't have any or any
interesting IP addresses. On macOS and iOS, for instance, there are a
ton of misc things.
But the link monitor based its are-there-changes decision on
interfaces.State.Equal, which just used reflect.DeepEqual, including
comparing all the boring interfaces. On macOS, when turning wifi on or off, there
are a ton of misc boring interface changes, resulting in hitting an earlier
check I'd added on suspicion this was happening:
[unexpected] network state changed, but stringification didn't
This fixes that by instead adding a new
interfaces.State.RemoveUninterestingInterfacesAndAddresses method that
does, uh, that. Then use that in the monitor. So then when Equal is
used later, it's DeepEqualing the already-cleaned version with only
interesting interfaces.
This makes cmd/tailscaled debug --monitor much less noisy.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Also change the type to netaddr.IP while here, because it made sorting
easier.
Updates tailscale/corp#1397
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The Engine.LinkChange method was recently removed in
e3df29d488 while misremembering how
Android's link state mechanism worked.
Rather than do some last minute rearchitecting of link state on
Android before Tailscale 1.6, restore the old Engine.LinkChange hook
for now so the Android client doesn't need any changes. But change how
it's implemented to instead inject an event into the link monitor.
Fixes#1427
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
FreeBSD tun devices don't work with the way we implement IPv6
https://github.com/tailscale/tailscale/issues/1307
At least for now, remove any IPv6 addresses from the netmap.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
This is necessary because either protocol can be disabled globally by a
Windows registry policy, at which point trying to touch that address
family results in "Element not found" errors. This change skips programming
address families that Windows tell us are unavailable.
Fixes#1396.
Signed-off-by: David Anderson <danderson@tailscale.com>
Not great, but lets people working on new ports get going more quickly
without having to do everything up front.
As the link monitor is getting used more, I felt bad having a useless
implementation.
Updates #815
Updates #1427
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
