X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fnet_packet.c;h=cbdc15cfebc98ea77156017b65db2c4beb3d472a;hb=19be9cf7150858311f7898fa3fb525d692d02f64;hp=3627f31d317bfcc122269b0a84a9eff6327900d5;hpb=33f241d97852d7a171f1aaf1bda7f66356ff889e;p=meshlink diff --git a/src/net_packet.c b/src/net_packet.c index 3627f31d..cbdc15cf 100644 --- a/src/net_packet.c +++ b/src/net_packet.c @@ -1,7 +1,7 @@ /* net_packet.c -- Handles in- and outgoing VPN packets Copyright (C) 1998-2005 Ivo Timmermans, - 2000-2011 Guus Sliepen + 2000-2012 Guus Sliepen 2010 Timothy Redaelli 2010 Brandon Black @@ -62,13 +62,21 @@ static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999 static void send_udppacket(node_t *, vpn_packet_t *); unsigned replaywin = 16; +bool localdiscovery = false; #define MAX_SEQNO 1073741824 -// mtuprobes == 1..30: initial discovery, send bursts with 1 second interval -// mtuprobes == 31: sleep pinginterval seconds -// mtuprobes == 32: send 1 burst, sleep pingtimeout second -// mtuprobes == 33: no response from other side, restart PMTU discovery process +/* mtuprobes == 1..30: initial discovery, send bursts with 1 second interval + mtuprobes == 31: sleep pinginterval seconds + mtuprobes == 32: send 1 burst, sleep pingtimeout second + mtuprobes == 33: no response from other side, restart PMTU discovery process + + Probes are sent in batches of three, with random sizes between the lower and + upper boundaries for the MTU thus far discovered. + + In case local discovery is enabled, a fourth packet is added to each batch, + which will be broadcast to the local network. +*/ static void send_mtu_probe_handler(int fd, short events, void *data) { node_t *n = data; @@ -79,7 +87,7 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { n->mtuprobes++; if(!n->status.reachable || !n->status.validkey) { - ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname); n->mtuprobes = 0; return; } @@ -91,14 +99,14 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { goto end; } - ifdebug(TRAFFIC) logger(LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname); n->mtuprobes = 1; n->minmtu = 0; n->maxmtu = MTU; } if(n->mtuprobes >= 10 && n->mtuprobes < 32 && !n->minmtu) { - ifdebug(TRAFFIC) logger(LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname); n->mtuprobes = 31; } @@ -108,7 +116,7 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { else n->maxmtu = n->minmtu; n->mtu = n->minmtu; - ifdebug(TRAFFIC) logger(LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes); + logger(DEBUG_TRAFFIC, LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes); n->mtuprobes = 31; } @@ -119,7 +127,7 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { timeout = pingtimeout; } - for(i = 0; i < 3; i++) { + for(i = 0; i < 3 + localdiscovery; i++) { if(n->maxmtu <= n->minmtu) len = n->maxmtu; else @@ -131,9 +139,12 @@ static void send_mtu_probe_handler(int fd, short events, void *data) { memset(packet.data, 0, 14); randomize(packet.data + 14, len - 14); packet.len = len; - packet.priority = 0; + if(i >= 3 && n->mtuprobes <= 10) + packet.priority = -1; + else + packet.priority = 0; - ifdebug(TRAFFIC) logger(LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname); send_udppacket(n, &packet); } @@ -149,7 +160,7 @@ void send_mtu_probe(node_t *n) { } static void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) { - ifdebug(TRAFFIC) logger(LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname); if(!packet->data[0]) { packet->data[0] = 1; @@ -231,7 +242,7 @@ static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t /* VPN packet I/O */ static void receive_packet(node_t *n, vpn_packet_t *packet) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Received packet of %d bytes from %s (%s)", + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Received packet of %d bytes from %s (%s)", packet->len, n->name, n->hostname); n->in_packets++; @@ -255,7 +266,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { size_t outlen; if(!cipher_active(&n->incipher)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", n->name, n->hostname); return; } @@ -263,7 +274,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { /* Check packet length */ if(inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)", + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got too short packet from %s (%s)", n->name, n->hostname); return; } @@ -273,7 +284,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { if(digest_active(&n->indigest)) { inpkt->len -= n->indigest.maclength; if(!digest_verify(&n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname); return; } } @@ -284,7 +295,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { outlen = MAXSIZE; if(!cipher_decrypt(&n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname); return; } @@ -301,16 +312,16 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { if(inpkt->seqno != n->received_seqno + 1) { if(inpkt->seqno >= n->received_seqno + replaywin * 8) { if(n->farfuture++ < replaywin >> 2) { - logger(LOG_WARNING, "Packet from %s (%s) is %d seqs in the future, dropped (%u)", + logger(DEBUG_ALWAYS, LOG_WARNING, "Packet from %s (%s) is %d seqs in the future, dropped (%u)", n->name, n->hostname, inpkt->seqno - n->received_seqno - 1, n->farfuture); return; } - logger(LOG_WARNING, "Lost %d packets from %s (%s)", + logger(DEBUG_ALWAYS, LOG_WARNING, "Lost %d packets from %s (%s)", inpkt->seqno - n->received_seqno - 1, n->name, n->hostname); memset(n->late, 0, replaywin); } else if (inpkt->seqno <= n->received_seqno) { if((n->received_seqno >= replaywin * 8 && inpkt->seqno <= n->received_seqno - replaywin * 8) || !(n->late[(inpkt->seqno / 8) % replaywin] & (1 << inpkt->seqno % 8))) { - logger(LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d", + logger(DEBUG_ALWAYS, LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d", n->name, n->hostname, inpkt->seqno, n->received_seqno); return; } @@ -338,7 +349,7 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { outpkt = pkt[nextpkt++]; if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression)) < 0) { - ifdebug(TRAFFIC) logger(LOG_ERR, "Error while uncompressing packet from %s (%s)", + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while uncompressing packet from %s (%s)", n->name, n->hostname); return; } @@ -381,10 +392,9 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { static int priority = 0; int origpriority = origpkt->priority; #endif - int sock; if(!n->status.reachable) { - ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname); return; } @@ -393,7 +403,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { if(!n->status.validkey) { time_t now = time(NULL); - ifdebug(TRAFFIC) logger(LOG_INFO, + logger(DEBUG_TRAFFIC, LOG_INFO, "No valid key known yet for %s (%s), forwarding via TCP", n->name, n->hostname); @@ -408,7 +418,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { } if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) { - ifdebug(TRAFFIC) logger(LOG_INFO, + logger(DEBUG_TRAFFIC, LOG_INFO, "Packet for %s (%s) larger than minimum MTU, forwarding via %s", n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP"); @@ -426,7 +436,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { outpkt = pkt[nextpkt++]; if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression)) < 0) { - ifdebug(TRAFFIC) logger(LOG_ERR, "Error while compressing packet to %s (%s)", + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)", n->name, n->hostname); return; } @@ -446,7 +456,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { outlen = MAXSIZE; if(!cipher_encrypt(&n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { - ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); goto end; } @@ -463,33 +473,58 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* Determine which socket we have to use */ - for(sock = 0; sock < listen_sockets; sock++) - if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family) - break; - - if(sock >= listen_sockets) - sock = 0; /* If none is available, just use the first and hope for the best. */ + if(n->address.sa.sa_family != listen_socket[n->sock].sa.sa.sa_family) { + for(int sock = 0; sock < listen_sockets; sock++) { + if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family) { + n->sock = sock; + break; + } + } + } /* Send the packet */ + struct sockaddr *sa; + socklen_t sl; + int sock; + + /* Overloaded use of priority field: -1 means local broadcast */ + + if(origpriority == -1 && n->prevedge) { + struct sockaddr_in in; + in.sin_family = AF_INET; + in.sin_addr.s_addr = -1; + in.sin_port = n->prevedge->address.in.sin_port; + sa = (struct sockaddr *)∈ + sl = sizeof in; + sock = 0; + } else { + if(origpriority == -1) + origpriority = 0; + + sa = &(n->address.sa); + sl = SALEN(n->address.sa); + sock = n->sock; + } + #if defined(SOL_IP) && defined(IP_TOS) if(priorityinheritance && origpriority != priority - && listen_socket[sock].sa.sa.sa_family == AF_INET) { + && listen_socket[n->sock].sa.sa.sa_family == AF_INET) { priority = origpriority; - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting outgoing packet priority to %d", priority); - if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof priority)) /* SO_PRIORITY doesn't seem to work */ - logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno)); + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Setting outgoing packet priority to %d", priority); + if(setsockopt(listen_socket[n->sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority))) /* SO_PRIORITY doesn't seem to work */ + logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno)); } #endif - if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa)) < 0 && !sockwouldblock(sockerrno)) { + if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) { if(sockmsgsize(sockerrno)) { if(n->maxmtu >= origlen) n->maxmtu = origlen - 1; if(n->mtu >= origlen) n->mtu = origlen - 1; } else - logger(LOG_ERR, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno)); + logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno)); } end: @@ -507,15 +542,15 @@ void send_packet(node_t *n, vpn_packet_t *packet) { memcpy(packet->data, mymac.x, ETH_ALEN); n->out_packets++; n->out_bytes += packet->len; - write_packet(packet); + devops.write(packet); return; } - ifdebug(TRAFFIC) logger(LOG_ERR, "Sending packet of %d bytes to %s (%s)", + logger(DEBUG_TRAFFIC, LOG_ERR, "Sending packet of %d bytes to %s (%s)", packet->len, n->name, n->hostname); if(!n->status.reachable) { - ifdebug(TRAFFIC) logger(LOG_INFO, "Node %s (%s) is not reachable", + logger(DEBUG_TRAFFIC, LOG_INFO, "Node %s (%s) is not reachable", n->name, n->hostname); return; } @@ -526,7 +561,7 @@ void send_packet(node_t *n, vpn_packet_t *packet) { via = (packet->priority == -1 || n->via == myself) ? n->nexthop : n->via; if(via != n) - ifdebug(TRAFFIC) logger(LOG_INFO, "Sending packet to %s via %s (%s)", + logger(DEBUG_TRAFFIC, LOG_INFO, "Sending packet to %s via %s (%s)", n->name, via->name, n->via->hostname); if(packet->priority == -1 || ((myself->options | via->options) & OPTION_TCPONLY)) { @@ -541,24 +576,50 @@ void send_packet(node_t *n, vpn_packet_t *packet) { void broadcast_packet(const node_t *from, vpn_packet_t *packet) { splay_node_t *node; connection_t *c; + node_t *n; - ifdebug(TRAFFIC) logger(LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)", + // Always give ourself a copy of the packet. + if(from != myself) + send_packet(myself, packet); + + // In TunnelServer mode, do not forward broadcast packets. + // The MST might not be valid and create loops. + if(tunnelserver || broadcast_mode == BMODE_NONE) + return; + + logger(DEBUG_TRAFFIC, LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)", packet->len, from->name, from->hostname); - if(from != myself) { - send_packet(myself, packet); + switch(broadcast_mode) { + // In MST mode, broadcast packets travel via the Minimum Spanning Tree. + // This guarantees all nodes receive the broadcast packet, and + // usually distributes the sending of broadcast packets over all nodes. + case BMODE_MST: + for(node = connection_tree->head; node; node = node->next) { + c = node->data; - // In TunnelServer mode, do not forward broadcast packets. - // The MST might not be valid and create loops. - if(tunnelserver) - return; - } + if(c->status.active && c->status.mst && c != from->nexthop->connection) + send_packet(c->node, packet); + } + break; - for(node = connection_tree->head; node; node = node->next) { - c = node->data; + // In direct mode, we send copies to each node we know of. + // However, this only reaches nodes that can be reached in a single hop. + // We don't have enough information to forward broadcast packets in this case. + case BMODE_DIRECT: + if(from != myself) + break; - if(c->status.active && c->status.mst && c != from->nexthop->connection) - send_packet(c->node, packet); + for(node = node_udp_tree->head; node; node = node->next) { + n = node->data; + + if(n->status.reachable && ((n->via == myself && n->nexthop == n) || n->via == n)) + send_packet(n, packet); + } + break; + + default: + break; } } @@ -570,11 +631,6 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) { static time_t last_hard_try = 0; time_t now = time(NULL); - if(last_hard_try == now) - return NULL; - else - last_hard_try = now; - for(node = edge_weight_tree->head; node; node = node->next) { e = node->data; @@ -597,6 +653,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) { if(hard) last_hard_try = now; + last_hard_try = now; return n; } @@ -612,7 +669,7 @@ void handle_incoming_vpn_data(int sock, short events, void *data) { if(len <= 0 || len > MAXSIZE) { if(!sockwouldblock(sockerrno)) - logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno)); + logger(DEBUG_ALWAYS, LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno)); return; } @@ -626,9 +683,9 @@ void handle_incoming_vpn_data(int sock, short events, void *data) { n = try_harder(&from, &pkt); if(n) update_node_udp(n, &from); - else ifdebug(PROTOCOL) { + else if(debug_level >= DEBUG_PROTOCOL) { hostname = sockaddr2hostname(&from); - logger(LOG_WARNING, "Received UDP packet from unknown source %s", hostname); + logger(DEBUG_PROTOCOL, LOG_WARNING, "Received UDP packet from unknown source %s", hostname); free(hostname); return; } @@ -636,6 +693,8 @@ void handle_incoming_vpn_data(int sock, short events, void *data) { return; } + n->sock = (intptr_t)data; + receive_udppacket(n, &pkt); } @@ -644,7 +703,7 @@ void handle_device_data(int sock, short events, void *data) { packet.priority = 0; - if(read_packet(&packet)) { + if(devops.read(&packet)) { myself->in_packets++; myself->in_bytes += packet.len; route(myself, &packet);