FEA: Fix tx Mcast packets with duplicate local IPs.

When multiple interfaces have the same IP, we must pass
in the interface ifindex instead of just the IP address
when binding the socket before sending mcast packets.

Keep fallback code for systems that do not support
ip_mreqn.  They will work fine as long as there are no
duplicate IP addresses.

Signed-off-by: Ben Greear <greearb@candelatech.com>

xorp/fea/data_plane/io/io_ip_socket.cc

@@ -465,8 +465,6 @@ IoIpSocket::set_default_multicast_interface(const string& if_name,
     switch (family()) {
     case AF_INET:
     {
-	struct in_addr in_addr;
-
 	// Find the first address
 	IfTreeVif::IPv4Map::const_iterator ai = vifp->ipv4addrs().begin();
 	if (ai == vifp->ipv4addrs().end()) {
@@ -476,15 +474,34 @@ IoIpSocket::set_default_multicast_interface(const string& if_name,
 				 if_name.c_str(), vif_name.c_str());
 	    return (XORP_ERROR);
 	}
+
 	const IfTreeAddr4& fa = *(ai->second);
 
+#ifdef HAVE_STRUCT_IP_MREQN
+	struct ip_mreqn mreqn;
+	memset(&mreqn, 0, sizeof(mreqn));
+
+	fa.addr().copy_out(mreqn.imr_address);
+	mreqn.imr_ifindex = vifp->pif_index();
+	if (setsockopt(_proto_socket_out, IPPROTO_IP, IP_MULTICAST_IF,
+		       XORP_SOCKOPT_CAST(&mreqn), sizeof(mreqn)) < 0) {
+	    error_msg = c_format("setsockopt(IP_MULTICAST_IF, %s %i) failed: %s",
+				 cstring(fa.addr()), vifp->pif_index(),
+				 XSTRERROR);
+	    return XORP_ERROR;
+	}
+#else
+	struct in_addr in_addr;
+	memset(&in_addr, 0, sizeof(in_addr));
+
 	fa.addr().copy_out(in_addr);
 	if (setsockopt(_proto_socket_out, IPPROTO_IP, IP_MULTICAST_IF,
 		       XORP_SOCKOPT_CAST(&in_addr), sizeof(in_addr)) < 0) {
 	    error_msg = c_format("setsockopt(IP_MULTICAST_IF, %s) failed: %s",
 				 cstring(fa.addr()), XSTRERROR);
 	    return (XORP_ERROR);
 	}
+#endif
     }
     break;
 

xorp/fea/io_ip.hh

@@ -17,8 +17,6 @@
 // XORP Inc, 2953 Bunker Hill Lane, Suite 204, Santa Clara, CA 95054, USA;
 // http://xorp.net
 
-// $XORP: xorp/fea/io_ip.hh,v 1.5 2008/10/02 21:56:48 bms Exp $
-
 
 #ifndef __FEA_IO_IP_HH__
 #define __FEA_IO_IP_HH__

xorp/fea/xrl_fea_target.cc

@@ -3696,6 +3696,10 @@ XrlFeaTarget::raw_packet4_0_1_send(
     vector<uint8_t> ext_headers_type_vector;
     vector<vector<uint8_t> > ext_headers_payload_vector;
 
+    //XLOG_INFO("FEA::send_raw pkt on %s/%s. from: %s to: %s",
+    //      if_name.c_str(), vif_name.c_str(),
+    //      src_address.str().c_str(), dst_address.str().c_str());
+
     if (_io_ip_manager.send(if_name, vif_name, IPvX(src_address),
 			    IPvX(dst_address), ip_protocol, ip_ttl, ip_tos,
 			    ip_router_alert, ip_internet_control,

xorp/pim/xrl_pim_node.cc

@@ -2385,9 +2385,9 @@ XrlPimNode::send_protocol_message()
     entry = dynamic_cast<SendProtocolMessage*>(xrl_task_base);
     XLOG_ASSERT(entry != NULL);
 
-    //XLOG_ERROR("XrlPimNode::send_protocol_message interface/vif %s/%s. ",
-    //       entry->if_name().c_str(),
-    //       entry->vif_name().c_str());
+    //XLOG_INFO("XrlPimNode::send_protocol_message interface/vif %s/%s. from: %s to: %s",
+    //      entry->if_name().c_str(), entry->vif_name().c_str(),
+    //      entry->src_address().str().c_str(), entry->dst_address().str().c_str());
 
     //
     // Check whether we have already registered with the FEA

xorp/site_scons/config/allconfig.py

@@ -415,12 +415,26 @@ def DoAllConfig(env, conf, host_os):
         prereq_netinet_ip_h.append('netinet/in.h')
     if has_netinet_in_systm_h:
 	prereq_netinet_ip_h.append('netinet/in_systm.h')
+    prereq_mreqn_h = prereq_netinet_ip_h
     has_netinet_ip_h = conf.CheckHeader(prereq_netinet_ip_h + ['netinet/ip.h'])
+    if has_netinet_ip_h:
+         prereq_mreqn_h.append('netinet/ip.h');
 
     has_netinet_tcp_h = conf.CheckHeader(['sys/param.h', 'sys/socket.h', 'netinet/in.h', 'netinet/in_systm.h', 'netinet/ip.h', 'netinet/tcp.h'])
     has_netinet_igmp_h = conf.CheckHeader(['sys/types.h', 'netinet/in.h', 'netinet/igmp.h'])
     has_netinet_ether_h = conf.CheckHeader('netinet/ether.h')
 
+    # Check for ip_mreqn struct.
+    mreqn_header_includes = []
+    for s in prereq_mreqn_h:
+        mreqn_header_includes.append("#include <%s>\n" % s)
+    mreqn_header_includes = string.join(mreqn_header_includes, '')
+    has_struct_ip_mreqn = conf.CheckType('struct ip_mreqn', includes=mreqn_header_includes)
+    if not has_struct_ip_mreqn:
+        print "\nWARNING: No struct ip_mreqn found.  Each interface must"
+        print "  have a unique IP address or IP multicast (at least) will not"
+        print "  be transmitted on the correct interface."
+
     # Header file <netinet/if_ether.h> might need <sys/types.h>, 
     # <sys/socket.h>, <net/if.h>, and/or <netinet/in.h>
     prereq_netinet_if_ether_h = []