1. Add TCP port forwarding.
For example: ./sniproxy -forwards=tcp/22/github.com
will forward SSH to github.
% ssh -i ~/.ssh/id_ecdsa.pem -T git@github.com
Hi GitHubUser! You've successfully authenticated, but GitHub does not
provide shell access.
% ssh -i ~/.ssh/id_ecdsa.pem -T git@100.65.x.y
Hi GitHubUser! You've successfully authenticated, but GitHub does not
provide shell access.
2. Additionally export clientmetrics as prometheus metrics for local
scraping over the tailnet: http://sniproxy-hostname:8080/debug/varz
Updates https://github.com/tailscale/tailscale/issues/1748
Signed-off-by: Denton Gentry <dgentry@tailscale.com>