HexInject is a hexadecimal and raw packet injector and sniffer. It can be easily combined with other tools to provide a powerful command line framework for raw network access. It will automatically set the correct checksum (IP, TCP, UDP, ICMP).
You can download it from the following link: https://packetstormsecurity.com/files/download/93733/hexinject-1.1.tar.gz
Source: https://packetstormsecurity.com/files/93733/HexInject-1.1.html