Application-level IP masquerading?

Question

On Windows XP, we would like an application to be able to send UDP packets "from" arbitrary IP4 addresses onto a [private] network that's connected to one of the computer's network cards. The receiving computer should believe that the packets originated from different devices.

Obviously socket.sendto() will just create packets that inherit the network card's IP address. But what additional hardware (or network-card configuration) is needed to make this work?

Answer 1

RAW sockets or RAW Ethernet sockets are likely the best solution. You can get a NDIS driver for RAW Ethernet sockets and then exercise in C or .Net as required.

• http://msdn.microsoft.com/en-us/library/ms740548(v=vs.85).aspx

• http://msdn.microsoft.com/en-us/library/ms740463(v=vs.85).aspx

RAW Ethernet means you will need to construct the Ethernet, IP, and UDP headers for each packet.

• http://www.rawether.net/

• http://www.codeproject.com/KB/IP/sendrawpacket.aspx

• http://msdn.microsoft.com/en-us/library/ff563732(v=vs.85).aspx