Packet Forwarding Fun!

[paulq]

I'm looking to write a program that will make a computer act as a firewall\router\gateway. I am using the WinPcap library to capture the packets promiscuously then I want to forward them to their proper destination. Will I need to forward them manually using WinPcap send packet function or is there a setting in Windows or WinPcap that allows the automatic forwarding of packets to the proper destination?

[paulq]

I may have answered my own question with this documentation (http://windowssdk.msdn.microsoft.com/en-us/library/ms690854.aspx).

The EnableRouter function turns on IP forwarding on the local computer. EnableRouter also increments a reference count that tracks the number of enable-IP-forwarding requests.
I will eventually try this out and keep everyone updated on how this works.

[paulq]

UPDATE: I have tried this on an WinXP Home machine and it works well. EnableRouter is the function to use to turn automatic IP Forwarding on in MS Windows.