A Go library implementation of the PROXY protocol, versions 1 and 2, which provides, as per specification:
(...) a convenient way to safely transport connection information such as a client's address across multiple layers of NAT or TCP proxies. It is designed to require little changes to existing components and to limit the performance impact caused by the processing of the transported information.
This library is to be used in one of or both proxy clients and proxy servers that need to support said protocol. Both protocol versions, 1 (text-based) and 2 (binary-based) are supported.
$ go get -u github.com/pires/go-proxyproto
package main
import (
"log"
"net"
proxyproto "github.com/pires/go-proxyproto"
)
func main() {
// Create a listener
addr := "localhost:9876"
list, err := net.Listen("tcp", addr)
if err != nil {
log.Fatalf("couldn't listen to %q: %q\n", addr, err.Error())
}
// Wrap listener in a proxyproto listener
proxyListener := &proxyproto.Listener{Listener: list}
defer proxyListener.Close()
// Wait for a connection and accept it
conn, err := proxyListener.Accept()
defer conn.Close()
// Print connection details
if conn.LocalAddr() == nil {
log.Fatal("couldn't retrieve local address")
}
log.Printf("local address: %q", conn.LocalAddr().String())
if conn.RemoteAddr() == nil {
log.Fatal("couldn't retrieve remote address")
}
log.Printf("remote address: %q", conn.RemoteAddr().String())
}