This library provides the proxyproto package which can be used for servers listening behind HAProxy of Amazon ELB load balancers. Those load balancers support the use of a proxy protocol (https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt), which provides a simple mechansim for the server to get the address of the client instead of the load balancer.

This library provides both a net.Listener and net.Conn implementation that can be used to handle situation in which you may be using the proxy protocol. Proxy protocol version 1 and 2 supported. Also this library supported mode as TLS server,

The only caveat is that we check for the header prefix to determine if the protocol is being used. If that string may occur as part of your input, then it is ambiguous if the protocol is being used and you may have problems.

proxy protocol version 2

Initial support for proxy protocol version 2, need more work but it's working.

Documentation

Full documentation can be found here.

Examples

Using the library in TCP mode:


// Create a listener
list, err := net.Listen("tcp", "...")

// Wrap listener in a proxyproto listener (TCP mode)
proxyList := &proxyproto.Listener{Listener: list}
conn, err := proxyList.Accept()

...

Using the library in TLS mode:


// Create a TLS server config
cer, err := tls.X509KeyPair([]byte(serverCert), []byte(serverKey))
if err != nil {
	log.Fatal(err)
}
config := &tls.Config{Certificates: []tls.Certificate{cer}}

// Create a listener
list, err := net.Listen("tcp", "...")

// Wrap listener in a proxyproto listener (TLS mode)
proxyList := &proxyproto.Listener{Listener: list, TLSConfig: config}
conn, err := proxyList.Accept()

...