It seems that all the setups that support split DNS understand
this distinction, and it's an important one when translating
high-level configuration.
Part of #953.
Signed-off-by: David Anderson <danderson@tailscale.com>
Correctly reports that Win7 cannot do split DNS, and has a helper to
discover the "base" resolvers for the system.
Part of #953
Signed-off-by: David Anderson <danderson@tailscale.com>
OS implementations are going to support split DNS soon.
Until they're all in place, hardcode Primary=true to get
the old behavior.
Signed-off-by: David Anderson <danderson@tailscale.com>
This is usually the same as the requested interface, but on some
unixes can vary based on device number allocation, and on Windows
it's the GUID instead of the pretty name, since everything relating
to configuration wants the GUID.
Signed-off-by: David Anderson <danderson@tailscale.com>
wgengine/router.CallbackRouter needs to support both the Router
and OSConfigurator interfaces, so the setters can't both be called
Set.
Signed-off-by: David Anderson <danderson@tailscale.com>
It existed to work around the frequent opening and closing
of the conn.Bind done by wireguard-go.
The preceding commit removed that behavior,
so we can simply close the connections
when we are done with them.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
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>