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>
We used to allow that, but now it just crashes.
Separately I need to figure out why it got into this path at all,
which is #1416.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Don't use os.NewFile or (*os.File).Close on the AF_ROUTE socket. It
apparently does weird things to the fd and at least doesn't seem to
close it. Just use the unix package.
The test doesn't actually fail reliably before the fix, though. It
was an attempt. But this fixes the integration tests.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Previously tailscaled on macOS was running "/sbin/route monitor" as a
child process, but child processes aren't allowed in the Network
Extension / App Store sandbox. Instead, just do what "/sbin/route monitor"
itself does: unix.Socket(unix.AF_ROUTE, unix.SOCK_RAW, 0) and read that.
We also parse it now, but don't do anything with the parsed results yet.
We will over time, as we have with Linux netlink messages over time.
Currently any message is considered a signal to poll and see what changed.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
