Mpctp is a tool for manipulation of raw packets that allows a large number of options. Its primary purpose is to diagnose and test several scenarios that involving the use of the types of TCP/IP packets. It is able to send certain types of packets to any specific target and manipulations of various fields at runtime. These fields can be modified in its structure as the the Source/Destination IP address and Source/Destination MAC address.
You can download it from the following link: https://packetstormsecurity.com/files/download/98504/mptcp-1.7-en.tar.gz
Source: https://packetstormsecurity.com/files/98504/Mptcp-Packet-Manipulator-1.7.html