Hi everyone. I've been pulling my hair out lately, using netfilter/ipq to try to add options to the TCP headers of outgoing packets. However, even just adding 4 bytes of no-op options results in subsequent incoming packets (via ipq_get_packet) looking mangled. (After adding the options, all appropriate fields were updated--checksums, length fields, etc. Also, I was extremely carefully to follow the specifications for adding the TCP options, proper padding, etc., etc. I'm pretty sure my problems do not have to do with the formatting of the packet.) So my hopefully simple question is, can packet sizes be changed and then reinjected using ipq_set_verdict? I found one reference that seemed to suggest that modified packets had to stay the same size. I've tested modifying packets without changing their overall byte sizes, and that does in fact seem to work (Eg, I changed the TTL field.). If the answer to the above question is 'yes', then I'll provide more details in the follow-up, in hopes of getting to the bottom of my troubles. Thanks in advance, -bj BJ Premore
