Merge IGMPv3 and Source-Specific Multicast (SSM) to the FreeBSD

IPv4 stack.

Diffs are minimized against p4.
PCS has been used for some protocol verification, more widespread
testing of recorded sources in Group-and-Source queries is needed.
sizeof(struct igmpstat) has changed.

__FreeBSD_version is bumped to 800070.

1 files changed, 3 insertions, 11 deletions

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index dcf282528ea3..a75ee72a3df8 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -592,7 +592,6 @@ passin:
 		return;
 	}
 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
-		struct in_multi *inm;
 		if (V_ip_mrouter) {
 			/*
 			 * If we are acting as a multicast router, all
@@ -619,17 +618,10 @@ passin:
 			V_ipstat.ips_forward++;
 		}
 		/*
-		 * See if we belong to the destination multicast group on the
-		 * arrival interface.
+		 * Assume the packet is for us, to avoid prematurely taking
+		 * a lock on the in_multi hash. Protocols must perform
+		 * their own filtering and update statistics accordingly.
 		 */
-		IN_MULTI_LOCK();
-		IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
-		IN_MULTI_UNLOCK();
-		if (inm == NULL) {
-			V_ipstat.ips_notmember++;
-			m_freem(m);
-			return;
-		}
 		goto ours;
 	}
 	if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)