Dear folks With U32 filter, I can filter packets with it's packet header. In linux, I wonder if Layer-7 filtering is possible. I want to filter packets that include specific pattern in it's payload(not header, data part). ex) Packets that include "aaa.exe" text pattern in it's data part. If it is possible, mail traffic that include specific text pattern can be filtered. I thought that above function is very useful. In Linux, is it possible?
