tcp handshake failed.client send rst (after syn-ack). can any one advice?

Posted by user1495181 on Server Fault See other posts from Server Fault or by user1495181
Published on 2012-07-03T15:16:06Z Indexed on 2012/07/03 15:17 UTC
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Filed under:

networking

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tcp

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linux-networking

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network-monitoring

architecture: 2 linux computer connected . on the second (192.168.1.1) one run apache server .

I have a small program that take tcp packets from nfqueue change the dst ip to 192.168.1.1 in case that the dst ip is 192.168.1.2 (i know that i can do it with iptables , but my program will do more things in the future), fix check sum and return to the queue.

if i call to telnet 192.168.1.1 , means that my program dosnt need to do any manipulation, handshake is OK. If i call to telnet 192.168.1.2 , my program change the dest. server get the syn and return syn-ack, but right after getting the syn-ack the client send rst.

Can anyone advice?

wireshark of the telnet tcpdump of the telenet above

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