I use iptables to put UDP packets into QUEUE. Then I take them,modify payload and want to put them back in QUEUE. Do I need to recalculate UDP checksum? If yes, could any of you give me a link of C code with UDP checksum?
Also should I use NF_QUEUE as a verdict?
status = ipq_set_verdict(h, m->packet_id,NF_QUEUE,m->data_len,BUFSIZE);