What kind of tools exist that can change the IP source address of an IP packet?

Question

I'm looking for a tool for Linux or Windows that modifies an IP header, to be precise the IP source address. I know it's impossible to get the answer to such a packet since you do not own the IP and back routing will fail but is this possible and how?

Answer 1

If you need to issue a packet with a different source address than your interface, rather than modify one on th fly, then hping is the tool commonly used. As answered previously, modification is best done by iptables.

Answer 2

How about something like this?

distinct Networking Tools

Modify and Send Packet. Software developers testing their application are able to capture a packet, quickly modify it to test the various needs of their application and resend it on the network.

The Packet Generator allows users to create a packet for test purposes and send it on the network to test it. The types of packets that can be created are ARP, Ethernet, ICMP, IP, TCP or UDP based. This feature is designed for software engineers to test out their own proprietary protocols by simulating particular situations and for system administrators to check for security holes in their network.

Here's some more information about IP Spoofing.

Answer 3

You'll need to create what is essentially a proxy server that will intercept the packets and modify them on the fly if you want this to be real-time. And that proxy server will have to be in a position to successfully intercept everything between your target and the internet or the rest of the network, depending on what sort of network you've got.

Answer 4

Depending on your needs, iptables in linux could be of help.

Say you have web server on port 8080, but you would like that anyone can access it on standard port 80. It is possible to configure iptables to redirect packet from port 8080 to 80 ( iptables will receive packet on port 80 , modify packets port to 8080 and forward it).

In similar sense, iptables can be configured to changed IP source or IP destination.

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