How to deal with SYN+ACK after receiving SYN

[Peng Wang]

Hi, all,

I encounter some problems when I want to modify TCP 3-way handshake. Suppose that a client send SYN to a server, and server will response SYN+ACK to the server. What can I do If I want to modify TCP header of SYN+ACK? Can you give me some hints or source code about it? Thank you very much!

Best,

Peng  

[Tommaso Pecorella]

Hi,

the SYN-ACK is sent at line 1827 of tcp-socket-base.cc

 SendEmptyPacket (TcpHeader::SYN | TcpHeader::ACK);

The header can not be modified easily, as it's a "normal" TCP header in an empty packet.

T.