X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet_packet.c;h=43c8ce20204db886b4b7ab2ece7afdd68c9f4b4c;hp=360f318e1ffacf7c5dd06a234b2a856e9f047e94;hb=c0af4c37d2046ffb3e07dd62f266a4fb99ea5614;hpb=6455654d26d204cea4bbc102e5bd6550b7fff7a7 diff --git a/src/net_packet.c b/src/net_packet.c index 360f318e..43c8ce20 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 @@ -61,13 +61,21 @@ 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. +*/ void send_mtu_probe(node_t *n) { vpn_packet_t packet; @@ -118,7 +126,7 @@ void send_mtu_probe(node_t *n) { timeout = pingtimeout; } - for(i = 0; i < 3; i++) { + for(i = 0; i < 3 + localdiscovery; i++) { if(n->maxmtu <= n->minmtu) len = n->maxmtu; else @@ -130,7 +138,10 @@ void send_mtu_probe(node_t *n) { memset(packet.data, 0, 14); RAND_pseudo_bytes(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); @@ -486,6 +497,29 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* 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[n->sock].sa.sa.sa_family == AF_INET) { @@ -496,14 +530,14 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { } #endif - if(sendto(listen_socket[n->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)); + ifdebug(TRAFFIC) logger(LOG_WARNING, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno)); } end: @@ -550,24 +584,50 @@ void send_packet(const node_t *n, vpn_packet_t *packet) { void broadcast_packet(const node_t *from, vpn_packet_t *packet) { avl_node_t *node; connection_t *c; + node_t *n; + + // 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; ifdebug(TRAFFIC) logger(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; + + // 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; - for(node = connection_tree->head; node; node = node->next) { - c = node->data; + 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(c->node, packet); + } + break; - if(c->status.active && c->status.mst && c != from->nexthop->connection) - send_packet(c->node, packet); + default: + break; } } @@ -600,6 +660,7 @@ 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; } @@ -610,7 +671,7 @@ void handle_incoming_vpn_data(int sock) { socklen_t fromlen = sizeof(from); node_t *n; - pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); + pkt.len = recvfrom(listen_socket[sock].udp, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); if(pkt.len < 0) { if(!sockwouldblock(sockerrno))