(WIP) PROXY protocol support

[chendo]

This PR is a hack that implements PROXY protocol (http://www.haproxy.org/download/1.5/doc/proxy-protocol.txt) which allows upstream TCP servers to be notified the original IP and port of the client.

Tested with nginx 1.7.9.

Sorry about whitespace changes and probable code quality as I'm not familiar with C and this is my first bit of work on an nginx module.

The function in question: https://github.com/yaoweibin/nginx_tcp_proxy_module/pull/110/files#diff-439a7558cb55631857d62112acec7449R237

Example configuration:

tcp {
  upstream backend {
    server 127.0.0.1:4221;

    accept_proxy on;
  }

  server {
    listen 4222;
    proxy_pass backend;
  }
}

Issues:

• The destination IP and port is wrong. I can't seem to find a proper reference to the socket the connection was accepted on. We don't use the destination IP/port anyway so it's not critical for us.

[yaoweibin]

Remove the useless spaces is good for me. Thank you.

I'm reviewing this pull request.

[yaoweibin]

Try the s->connection->local_sockaddr, it should store the destination address.

[chendo]

I gave it a go, doesn't seem to return the correct values either. IP is 0.0.0.0 and the port is not the port defined in the configuration. Not that important anyway IMO

[aderumier]

Hi, any news about this PR ?