svn commit: r291364 - head/sys/netinet

[Michael Tuexen]

Author: tuexen
Date: Thu Nov 26 09:25:20 2015
New Revision: 291364
URL: https://svnweb.freebsd.org/changeset/base/291364

Log:
  When receiving an SCTP/UDP packet and the interface performed
  the UDP checksum computation and signals that it was OK,
  clear this bit when passing the packet to SCTP. Since the
  bits indicating a valid UDP checksum and a valid SCTP
  checksum are the same, the SCTP stack would assume
  that also an SCTP checksum check has been performed.
  
  MFC after: 1 week

Modified:
  head/sys/netinet/sctputil.c

Modified: head/sys/netinet/sctputil.c
==============================================================================
--- head/sys/netinet/sctputil.c	Thu Nov 26 08:58:13 2015	(r291363)
+++ head/sys/netinet/sctputil.c	Thu Nov 26 09:25:20 2015	(r291364)
@@ -6957,6 +6957,18 @@ sctp_recv_udp_tunneled_packet(struct mbu
 	for (last = m; last->m_next; last = last->m_next);
 	last->m_next = sp;
 	m->m_pkthdr.len += sp->m_pkthdr.len;
+	/*
+	 * The CSUM_DATA_VALID flags indicates that the HW checked the UDP
+	 * checksum and it was valid. Since CSUM_DATA_VALID ==
+	 * CSUM_SCTP_VALID this would imply that the HW also verified the
+	 * SCTP checksum. Therefore, clear the bit.
+	 */
+	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
+	    "sctp_recv_udp_tunneled_packet(): Packet of length %d received on %s with csum_flags 0x%b.\n",
+	    m->m_pkthdr.len,
+	    if_name(m->m_pkthdr.rcvif),
+	    (int)m->m_pkthdr.csum_flags, CSUM_BITS);
+	m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
 	iph = mtod(m, struct ip *);
 	switch (iph->ip_v) {
 #ifdef INET