PacGen is an Ethernet IP TCP/UDP packet generating tool for Linux. Experimental ARP generation is included. Experimental ARP generation is included. This tool enables custom packets with configurable Ethernet, IP, TCP, and UDP layers as well as custom payloads. As an added feature there are configurations for packet count and a programmable time interval between packet sends. Plaintext config files control all the functions and represent all layers used to build packets. Included in the archive is the source code and a recompiled binary along with example configs.

Since I didn't write a smart interface routine, pacgen will only work with eth0. If you need to use a different interface the source code is pretty obvious on where this would be changed.