Only enable forwarding for an IP family if any forwarding is required
for that family.
Fixes#6221.
Signed-off-by: David Anderson <danderson@tailscale.com>
The //go:build syntax was introduced in Go 1.17:
https://go.dev/doc/go1.17#build-lines
gofmt has kept the +build and go:build lines in sync since
then, but enough time has passed. Time to remove them.
Done with:
perl -i -npe 's,^// \+build.*\n,,' $(git grep -l -F '+build')
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This implements the same functionality as the former run.sh, but in Go
and with a little better awareness of tailscaled's lifecycle.
Also adds TS_AUTH_ONCE, which fixes the unfortunate behavior run.sh had
where it would unconditionally try to reauth every time if you gave it
an authkey, rather than try to use it only if auth is actually needed.
This makes it a bit nicer to deploy these containers in automation, since
you don't have to run the container once, then go and edit its definition
to remove authkeys.
Signed-off-by: David Anderson <danderson@tailscale.com>