bcast-forward

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

Installation

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

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

Usage

You can run bcast-forward 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"
  -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 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.