s3:nmbd: also listen explicit on the subnet broadcast addresses

And send replies always via the unicast address of the subnet.

This behavior is off by default (as before)
and can be enabled with "nmbd:bind explicit broadcast = yes".

metze

1 files changed, 125 insertions, 64 deletions

diff --git a/source3/nmbd/nmbd_packets.c b/source3/nmbd/nmbd_packets.c
index 6136c6d171..013ebf6589 100644
--- a/source3/nmbd/nmbd_packets.c
+++ b/source3/nmbd/nmbd_packets.c
@@ -207,7 +207,8 @@ static struct packet_struct *create_and_init_netbios_packet(struct nmb_name *nmb
 
 	packet->ip = to_ip;
 	packet->port = NMB_PORT;
-	packet->fd = ClientNMB;
+	packet->recv_fd = -1;
+	packet->send_fd = ClientNMB;
 	packet->timestamp = time(NULL);
 	packet->packet_type = NMB_PACKET;
 	packet->locked = False;
@@ -258,7 +259,8 @@ static bool create_and_init_additional_record(struct packet_struct *packet,
 	   our standard refresh cycle for that name which copes nicely
 	   with disconnected networks.
 	*/
-	packet->fd = find_subnet_fd_for_address(*register_ip);
+	packet->recv_fd = -1;
+	packet->send_fd = find_subnet_fd_for_address(*register_ip);
 
 	return True;
 }
@@ -743,7 +745,7 @@ struct response_record *queue_query_name( struct subnet_record *subrec,
 			}
 
 			DEBUG(10,("queue_query_name: using source IP %s\n",inet_ntoa(*ifip)));
-				p->fd = find_subnet_fd_for_address( *ifip );
+				p->send_fd = find_subnet_fd_for_address( *ifip );
 				break;
 		}
 	}
@@ -979,9 +981,14 @@ for id %hu\n", packet_type, nmb_namestr(&orig_nmb->question.question_name),
 	}
 
 	packet.packet_type = NMB_PACKET;
+	packet.recv_fd = -1;
 	/* Ensure we send out on the same fd that the original
 		packet came in on to give the correct source IP address. */
-	packet.fd = orig_packet->fd;
+	if (orig_packet->send_fd != -1) {
+		packet.send_fd = orig_packet->send_fd;
+	} else {
+		packet.send_fd = orig_packet->recv_fd;
+	}
 	packet.timestamp = time(NULL);
 
 	debug_nmb_packet(&packet);
@@ -1679,50 +1686,74 @@ static bool create_listen_fdset(fd_set **ppset, int **psock_array, int *listen_n
 		return True;
 	}
 
+	/* The Client* sockets */
+	count++;
+
 	/* Check that we can add all the fd's we need. */
 	for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
 		count++;
 
-	if((count*2) + 2 > FD_SETSIZE) {
+	/* each interface gets 4 sockets */
+	count *= 4;
+
+	if(count > FD_SETSIZE) {
 		DEBUG(0,("create_listen_fdset: Too many file descriptors needed (%d). We can \
-only use %d.\n", (count*2) + 2, FD_SETSIZE));
+only use %d.\n", count, FD_SETSIZE));
 		SAFE_FREE(pset);
 		return True;
 	}
 
-	if((sock_array = SMB_MALLOC_ARRAY(int, (count*2) + 2)) == NULL) {
-		DEBUG(0,("create_listen_fdset: malloc fail for socket array.\n"));
+	if((sock_array = SMB_MALLOC_ARRAY(int, count)) == NULL) {
+		DEBUG(0,("create_listen_fdset: malloc fail for socket array. size %d\n", count));
 		SAFE_FREE(pset);
 		return True;
 	}
 
 	FD_ZERO(pset);
 
-	/* Add in the broadcast socket on 137. */
+	/* Add in the lp_socket_address() interface on 137. */
 	FD_SET(ClientNMB,pset);
 	sock_array[num++] = ClientNMB;
 	*maxfd = MAX( *maxfd, ClientNMB);
 
+	/* the lp_socket_address() interface has only one socket */
+	sock_array[num++] = -1;
+
 	/* Add in the 137 sockets on all the interfaces. */
 	for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec)) {
 		FD_SET(subrec->nmb_sock,pset);
 		sock_array[num++] = subrec->nmb_sock;
 		*maxfd = MAX( *maxfd, subrec->nmb_sock);
+
+		sock_array[num++] = subrec->nmb_bcast;
+		if (subrec->nmb_bcast != -1) {
+			FD_SET(subrec->nmb_bcast,pset);
+			*maxfd = MAX( *maxfd, subrec->nmb_bcast);
+		}
 	}
 
-	/* Add in the broadcast socket on 138. */
+	/* Add in the lp_socket_address() interface on 138. */
 	FD_SET(ClientDGRAM,pset);
 	sock_array[num++] = ClientDGRAM;
 	*maxfd = MAX( *maxfd, ClientDGRAM);
 
+	/* the lp_socket_address() interface has only one socket */
+	sock_array[num++] = -1;
+
 	/* Add in the 138 sockets on all the interfaces. */
 	for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec)) {
 		FD_SET(subrec->dgram_sock,pset);
 		sock_array[num++] = subrec->dgram_sock;
 		*maxfd = MAX( *maxfd, subrec->dgram_sock);
+
+		sock_array[num++] = subrec->dgram_bcast;
+		if (subrec->dgram_bcast != -1) {
+			FD_SET(subrec->dgram_bcast,pset);
+			*maxfd = MAX( *maxfd, subrec->dgram_bcast);
+		}
 	}
 
-	*listen_number = (count*2) + 2;
+	*listen_number = count;
 
 	SAFE_FREE(*ppset);
 	SAFE_FREE(*psock_array);
@@ -1811,61 +1842,90 @@ bool listen_for_packets(bool run_election)
 #endif
 
 	for(i = 0; i < listen_number; i++) {
+		enum packet_type packet_type;
+		struct packet_struct *packet;
+		const char *packet_name;
+		int client_fd;
+		int client_port;
+
+		if (sock_array[i] == -1) {
+			continue;
+		}
+
+		if (!FD_ISSET(sock_array[i],&r_fds)) {
+			continue;
+		}
+
 		if (i < (listen_number/2)) {
-			/* Processing a 137 socket. */
-			if (FD_ISSET(sock_array[i],&r_fds)) {
-				struct packet_struct *packet = read_packet(sock_array[i], NMB_PACKET);
-				if (packet) {
-					/*
-					 * If we got a packet on the broadcast socket and interfaces
-					 * only is set then check it came from one of our local nets. 
-					 */
-					if(lp_bind_interfaces_only() && (sock_array[i] == ClientNMB) && 
-								(!is_local_net_v4(packet->ip))) {
-						DEBUG(7,("discarding nmb packet sent to broadcast socket from %s:%d\n",
-							inet_ntoa(packet->ip),packet->port));	  
-						free_packet(packet);
-					} else if ((is_loopback_ip_v4(packet->ip) || 
-								ismyip_v4(packet->ip)) && packet->port == global_nmb_port &&
-								packet->packet.nmb.header.nm_flags.bcast) {
-						DEBUG(7,("discarding own bcast packet from %s:%d\n",
-							inet_ntoa(packet->ip),packet->port));	  
-						free_packet(packet);
-					} else {
-						/* Save the file descriptor this packet came in on. */
-						packet->fd = sock_array[i];
-						queue_packet(packet);
-					}
-				}
-			}
+			/* Port 137 */
+			packet_type = NMB_PACKET;
+			packet_name = "nmb";
+			client_fd = ClientNMB;
+			client_port = global_nmb_port;
 		} else {
-			/* Processing a 138 socket. */
-				if (FD_ISSET(sock_array[i],&r_fds)) {
-				struct packet_struct *packet = read_packet(sock_array[i], DGRAM_PACKET);
-				if (packet) {
-					/*
-					 * If we got a packet on the broadcast socket and interfaces
-					 * only is set then check it came from one of our local nets. 
-					 */
-					if(lp_bind_interfaces_only() && (sock_array[i] == ClientDGRAM) && 
-								(!is_local_net_v4(packet->ip))) {
-						DEBUG(7,("discarding dgram packet sent to broadcast socket from %s:%d\n",
-						inet_ntoa(packet->ip),packet->port));	  
-						free_packet(packet);
-					} else if ((is_loopback_ip_v4(packet->ip) || 
-							ismyip_v4(packet->ip)) && packet->port == DGRAM_PORT) {
-						DEBUG(7,("discarding own dgram packet from %s:%d\n",
-							inet_ntoa(packet->ip),packet->port));	  
-						free_packet(packet);
-					} else {
-						/* Save the file descriptor this packet came in on. */
-						packet->fd = sock_array[i];
-						queue_packet(packet);
-					}
-				}
+			/* Port 137 */
+			packet_type = DGRAM_PACKET;
+			packet_name = "dgram";
+			client_fd = ClientDGRAM;
+			client_port = DGRAM_PORT;
+		}
+
+		packet = read_packet(sock_array[i], packet_type);
+		if (!packet) {
+			continue;
+		}
+
+		/*
+		 * If we got a packet on the broadcast socket and interfaces
+		 * only is set then check it came from one of our local nets.
+		 */
+		if (lp_bind_interfaces_only() &&
+		    (sock_array[i] == client_fd) &&
+		    (!is_local_net_v4(packet->ip))) {
+			DEBUG(7,("discarding %s packet sent to broadcast socket from %s:%d\n",
+				packet_name, inet_ntoa(packet->ip), packet->port));
+			free_packet(packet);
+			continue;
+		}
+
+		if ((is_loopback_ip_v4(packet->ip) || ismyip_v4(packet->ip)) &&
+		    packet->port == client_port)
+		{
+			if (client_port == DGRAM_PORT) {
+				DEBUG(7,("discarding own dgram packet from %s:%d\n",
+					inet_ntoa(packet->ip),packet->port));
+				free_packet(packet);
+				continue;
 			}
-		} /* end processing 138 socket. */
-	} /* end for */
+
+			if (packet->packet.nmb.header.nm_flags.bcast) {
+				DEBUG(7,("discarding own nmb bcast packet from %s:%d\n",
+					inet_ntoa(packet->ip),packet->port));
+				free_packet(packet);
+				continue;
+			}
+		}
+
+		/*
+		 * 0,2,4,... are unicast sockets
+		 * 1,3,5,... are broadcast sockets
+		 *
+		 * on broadcast socket we only receive packets
+		 * and send replies via the unicast socket.
+		 *
+		 * 0,1 and 2,3 and ... belong together.
+		 */
+		if ((i % 2) != 0) {
+			/* this is a broadcast socket */
+			packet->send_fd = sock_array[i-1];
+		} else {
+			/* this is already a unicast socket */
+			packet->send_fd = sock_array[i];
+		}
+
+		queue_packet(packet);
+	}
+
 	return False;
 }
 
@@ -1946,7 +2006,8 @@ bool send_mailslot(bool unique, const char *mailslot,char *buf, size_t len,
 
 	p.ip = dest_ip;
 	p.port = dest_port;
-	p.fd = find_subnet_mailslot_fd_for_address( src_ip );
+	p.recv_fd = -1;
+	p.send_fd = find_subnet_mailslot_fd_for_address( src_ip );
 	p.timestamp = time(NULL);
 	p.packet_type = DGRAM_PACKET;