audriusbutkevicius / go-nat-pmp

A Go language client for the NAT-PMP internet protocol for port mapping and discovering the external IP address of a firewall.

go-nat-pmp

A Go language client for the NAT-PMP internet protocol for port mapping and discovering the external IP address of a firewall.

NAT-PMP is supported by Apple brand routers and open source routers like Tomato and DD-WRT.

See http://tools.ietf.org/html/draft-cheshire-nat-pmp-03

Get the package

go get -u github.com/jackpal/go-nat-pmp

Usage

import natpmp "github.com/jackpal/go-nat-pmp"

client := natpmp.NewClient(gatewayIP)
response, err := client.GetExternalAddress()
if err != nil {
    return
}
print("External IP address:", response.ExternalIPAddress)

Notes

There doesn't seem to be an easy way to programmatically determine the address of the default gateway. (Linux and OSX have a "routes" kernel API that can be examined to get this information, but there is no Go package for getting this information.)

Clients

This library is used in the Taipei Torrent BitTorrent client http://github.com/jackpal/Taipei-Torrent

Complete documentation

http://godoc.org/github.com/jackpal/go-nat-pmp

License

This project is licensed under the Apache License 2.0.