This feature is "registered" as an ipnlocal.Extension, and
conditionally linked depending on GOOS and ts_omit_relayserver build
tag.
The feature is not linked on iOS in attempt to limit the impact to
binary size and resulting effect of pushing up against NetworkExtension
limits. Eventually we will want to support the relay server on iOS,
specifically on the Apple TV. Apple TVs are well-fitted to act as
underlay relay servers as they are effectively always-on servers.
This skeleton begins to tie a PeerAPI endpoint to a net/udprelay.Server.
The PeerAPI endpoint is currently no-op as
extension.shouldRunRelayServer() always returns false. Follow-up commits
will implement extension.shouldRunRelayServer().
Updates tailscale/corp#27502
Signed-off-by: Jordan Whited <jordan@tailscale.com>
Jordan Whited