Hi all, Where is the ID field of the IPv4 header created when the DF flag is set? I am looking at ip_build_and_send_pkt. The code seems to have changed in 4.4-rc1:
if (ip_dont_fragment(sk, &rt->dst)) { iph->frag_off = htons(IP_DF); iph->id = 0; } else { iph->frag_off = 0; __ip_select_ident(net, iph, 1); } old code (executed irrespective of DF or not): ip_select_ident(sock_net(sk), skb, sk); The code in Stevens is basically iph->id = htons(ip_ident++) and now it seems to be calculated based on a hash + lookup table. So where is the id of 0 overwritten when DF is set? Didn't find any info in the docs. P.S. - is this the right mailing list for these kind of questions? Thanks!