bcast-forward-pcap

bcast-forward-pcap is a command line tool that forwards UDP broadcast packets with destination IP 255.255.255.255 received on a network interface to a specified list of unicast addresses possibly on other network interfaces. For example, it can be used for playing old LAN games, that use broadcasts to discover game servers, over a VPN tunnel. bcast-forward-pcap uses pcap for receiving and sending packets. For an IP/UDP raw socket version, see bcast-forward.

Installation

You can download and install bcast-forward-pcap with its dependencies to your GOPATH or GOBIN with the go tool:

$ go install github.com/hwipl/bcast-forward-pcap/cmd/bcast-forward-pcap

Note: you also need to have (lib)pcap installed on your system to use bcast-forward-pcap.

Usage

You can run bcast-forward-pcap with the following command line arguments:

  -d IPs
        forward broadcast packets to this comma-separated list of IPs, e.g.,
        "192.168.1.1,192.168.1.2"
  -i interface
        read packets from this network interface
  -keep-source-ip
        keep source address
  -p port
        only forward packets with this destination port (default 6112)
  -s IP
        rewrite source address to this IP

By default, bcast-forward-pcap rewrites the source IP address in forwarded packets to an IP address that is determined by the forwarding host's routing to each destination unicast address, usually an address of the outgoing network interface. Alternatively, you can specify a single IP address with -s that will be used as source IP address for all destination addresses. If you want to keep the original sender's IP address, you can disable source IP address rewriting completely with -keep-source-ip.