Author: lidl Date: Thu Sep 29 19:45:24 2016 New Revision: 306458 URL: https://svnweb.freebsd.org/changeset/base/306458
Log: Properly preserve ip_tos bits for IPv4 packets Restructure code slightly to save ip_tos bits earlier. Fix the bug where the ip_tos field is zeroed out before assigning to the iptos variable. Restore the ip_tos and ip_ver fields only if they have been zeroed during the pseudo-header checksum calculation. Reviewed by: cem, gnn, hiren MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D8053 Modified: head/sys/netinet/tcp_input.c Modified: head/sys/netinet/tcp_input.c ============================================================================== --- head/sys/netinet/tcp_input.c Thu Sep 29 18:24:29 2016 (r306457) +++ head/sys/netinet/tcp_input.c Thu Sep 29 19:45:24 2016 (r306458) @@ -603,7 +603,7 @@ tcp_input(struct mbuf **mp, int *offp, i #ifdef TCP_SIGNATURE uint8_t sig_checked = 0; #endif - uint8_t iptos = 0; + uint8_t iptos; struct m_tag *fwd_tag = NULL; #ifdef INET6 struct ip6_hdr *ip6 = NULL; @@ -675,6 +675,7 @@ tcp_input(struct mbuf **mp, int *offp, i /* XXX stat */ goto drop; } + iptos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; } #endif #if defined(INET) && defined(INET6) @@ -701,6 +702,7 @@ tcp_input(struct mbuf **mp, int *offp, i th = (struct tcphdr *)((caddr_t)ip + off0); tlen = ntohs(ip->ip_len) - off0; + iptos = ip->ip_tos; if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) th->th_sum = m->m_pkthdr.csum_data; @@ -721,29 +723,20 @@ tcp_input(struct mbuf **mp, int *offp, i ipov->ih_len = htons(tlen); th->th_sum = in_cksum(m, len); /* Reset length for SDT probes. */ - ip->ip_len = htons(tlen + off0); + ip->ip_len = htons(len); + /* Reset TOS bits */ + ip->ip_tos = iptos; + /* Re-initialization for later version check */ + ip->ip_v = IPVERSION; } if (th->th_sum) { TCPSTAT_INC(tcps_rcvbadsum); goto drop; } - /* Re-initialization for later version check */ - ip->ip_v = IPVERSION; } #endif /* INET */ -#ifdef INET6 - if (isipv6) - iptos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; -#endif -#if defined(INET) && defined(INET6) - else -#endif -#ifdef INET - iptos = ip->ip_tos; -#endif - /* * Check that TCP offset makes sense, * pull out TCP options and adjust length. XXX _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
