Destination IP Faking?

Question

I have a closed-source Windows 7 application that wants to make an HTTP connection to an internet-resident IP address. I want it to instead make it connect to a LAN IP address.

If the application went after a DNS entry, I would just let my internal DNS server dictate where the resource is, or change the HOSTS file. But it's not using DNS, just IP.

I tried using the Windows route commands but nothing seems to work.

Can anyone recommend an OS-level workaround to proxy/fake/route one IP address with another?

Thanks.

Answer 1

Depending on how concerned you are about reachability you could simply bring up a second IP address on your Windows box and on the server, where the servers IP address is the IP address you are trying to fake, and the Windows box IP address is in the same subnet. The easiest way to do this would be to use the same class C, ig if the address you are trying to fake is 1.2.3.4 make your servers IP 1.2.3.4 and your windows box 1.2.3.2 with a netmask of 255.255.255.0. THIS WILL HAVE THE BAD SIDE EFFECT OF MAKING EVERYTHING ELSE IN THE RANGE 1.2.3.x unreachable. You can mitigate this with a smaller netmask - but before I can advise that I'd need to know the last digit of the target IP address.

Also, can you advise what router you are using ? ( I know one can catch and mangle IP addresses under Linux to do what you want, and there is an outside chance you could do something similar with your router if we know what it is)