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 common Linux start-up path (fallback file defined but not
existing) was missing the log print of initializing Prefs. The code
was too twisty. Simplify a bit.
Updates #1573
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
They need some rework to do the right thing, in the meantime the direct
and resolvconf managers will work out.
The resolved implementation was never selected due to control-side settings.
The networkmanager implementation mostly doesn't get selected due to
unforeseen interactions with `resolvconf` on many platforms.
Both implementations also need rework to support the various routing modes
they're capable of.
Signed-off-by: David Anderson <danderson@tailscale.com>
It's only use to skip some optional initialization during cleanup,
but that work is very minor anyway, and about to change drastically.
Signed-off-by: David Anderson <danderson@tailscale.com>
It's currently unused, and no longer makes sense with the upcoming
DNS infrastructure. Keep it in tailcfg for now, since we need protocol
compat for a bit longer.
Signed-off-by: David Anderson <danderson@tailscale.com>
Old macOS clients required we populate this field to a non-null
value so we were unable to remove this field before.
Instead, keep the field but change its type to a custom empty struct
that can marshal/unmarshal JSON. And lock it in with a test.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The bool was already called useNetstack at the caller.
isUserspace (to mean netstack) is confusing next to wgengine.NewUserspaceEngine, as that's
a different type of 'userspace'.
Signed-off-by: Brad Fitzpatrick <bradfitz@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>
They're only used internally and in tests, and have surprising
semantics in that they only resolve MagicDNS names, not upstream
resolver queries.
Signed-off-by: David Anderson <danderson@tailscale.com>
This adds a new ipn.MaskedPrefs embedding a ipn.Prefs, along with a
bunch of "has bits", kept in sync with tests & reflect.
Then it adds a Prefs.ApplyEdits(MaskedPrefs) method.
Then the ipn.Backend interface loses its weirdo SetWantRunning(bool)
method (that I added in 483141094c for "tailscale down")
and replaces it with EditPrefs (alongside the existing SetPrefs for now).
Then updates 'tailscale down' to use EditPrefs instead of SetWantRunning.
In the future, we can use this to do more interesting things with the
CLI, reconfiguring only certain properties without the reset-the-world
"tailscale up".
Updates #1436
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We were going to remove this in Tailscale 1.3 but forgot.
This means Tailscale 1.8 users won't be able to downgrade to Tailscale
1.0, but that's fine.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Adding a subcommand which prints and logs a log marker. This should help
diagnose any issues that users face.
Fixes#1466
Signed-off-by: Maisem Ali <maisem@tailscale.com>
