X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet_packet.c;h=4bbb2d6f16e560bd5911addf946b8ca379d713fc;hb=b811e980e3a2a301c019459b91df2252468fd572;hp=cd8d98ac0b94cb602a738752f771cfa1d6102af2;hpb=236b0ba4ebba01e22e382e79897100338a039bbb;p=tinc diff --git a/src/net_packet.c b/src/net_packet.c index cd8d98ac..4bbb2d6f 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, - 2000-2012 Guus Sliepen + 2000-2013 Guus Sliepen 2010 Timothy Redaelli 2010 Brandon Black @@ -22,12 +22,6 @@ #include "system.h" -#include -#include -#include -#include -#include - #ifdef HAVE_ZLIB #include #endif @@ -36,12 +30,13 @@ #include LZO1X_H #endif -#include "avl_tree.h" +#include "cipher.h" #include "conf.h" #include "connection.h" +#include "crypto.h" +#include "digest.h" #include "device.h" #include "ethernet.h" -#include "event.h" #include "graph.h" #include "logger.h" #include "net.h" @@ -53,7 +48,6 @@ #include "xalloc.h" int keylifetime = 0; -int keyexpires = 0; #ifdef HAVE_LZO static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS]; #endif @@ -62,6 +56,7 @@ static void send_udppacket(node_t *, vpn_packet_t *); unsigned replaywin = 16; bool localdiscovery = false; +sockaddr_t localdiscovery_address; #define MAX_SEQNO 1073741824 @@ -70,23 +65,25 @@ bool localdiscovery = false; 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. + Probes are sent in batches of at least three, with random sizes between the + lower and upper boundaries for the MTU thus far discovered. + + After the initial discovery, a fourth packet is added to each batch with a + size larger than the currently known PMTU, to test if the PMTU has increased. - In case local discovery is enabled, a fourth packet is added to each batch, + In case local discovery is enabled, another 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; - int len, i; +static void send_mtu_probe_handler(void *data) { + node_t *n = data; int timeout = 1; - + n->mtuprobes++; - n->mtuevent = NULL; 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; } @@ -98,14 +95,15 @@ void send_mtu_probe(node_t *n) { 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->status.udp_confirmed = false; 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; } @@ -115,7 +113,7 @@ void send_mtu_probe(node_t *n) { 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; } @@ -126,54 +124,123 @@ void send_mtu_probe(node_t *n) { timeout = pingtimeout; } - for(i = 0; i < 3 + localdiscovery; i++) { - if(n->maxmtu <= n->minmtu) + for(int i = 0; i < 4 + localdiscovery; i++) { + int len; + + if(i == 0) { + if(n->mtuprobes < 30 || n->maxmtu + 8 >= MTU) + continue; + len = n->maxmtu + 8; + } else if(n->maxmtu <= n->minmtu) { len = n->maxmtu; - else + } else { len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu); + } if(len < 64) len = 64; - + + vpn_packet_t packet; memset(packet.data, 0, 14); - RAND_pseudo_bytes(packet.data + 14, len - 14); + randomize(packet.data + 14, len - 14); packet.len = len; - if(i >= 3 && n->mtuprobes <= 10) + if(i >= 4 && 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); } + n->probe_counter = 0; + gettimeofday(&n->probe_time, NULL); + + /* Calculate the packet loss of incoming traffic by comparing the rate of + packets received to the rate with which the sequence number has increased. + */ + + if(n->received > n->prev_received) + n->packetloss = 1.0 - (n->received - n->prev_received) / (float)(n->received_seqno - n->prev_received_seqno); + else + n->packetloss = n->received_seqno <= n->prev_received_seqno; + + n->prev_received_seqno = n->received_seqno; + n->prev_received = n->received; + end: - n->mtuevent = new_event(); - n->mtuevent->handler = (event_handler_t)send_mtu_probe; - n->mtuevent->data = n; - n->mtuevent->time = now + timeout; - event_add(n->mtuevent); + timeout_set(&n->mtutimeout, &(struct timeval){timeout, rand() % 100000}); } -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); +void send_mtu_probe(node_t *n) { + timeout_add(&n->mtutimeout, send_mtu_probe_handler, n, &(struct timeval){1, 0}); + send_mtu_probe_handler(n); +} + +static void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) { + logger(DEBUG_TRAFFIC, LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname); if(!packet->data[0]) { + /* It's a probe request, send back a reply */ + packet->data[0] = 1; + + /* Temporarily set udp_confirmed, so that the reply is sent + back exactly the way it came in. */ + + bool udp_confirmed = n->status.udp_confirmed; + n->status.udp_confirmed = true; send_udppacket(n, packet); + n->status.udp_confirmed = udp_confirmed; } else { + /* It's a valid reply: now we know bidirectional communication + is possible using the address and socket that the reply + packet used. */ + + n->status.udp_confirmed = true; + + /* If we haven't established the PMTU yet, restart the discovery process. */ + if(n->mtuprobes > 30) { + if (len == n->maxmtu + 8) { + logger(DEBUG_TRAFFIC, LOG_INFO, "Increase in PMTU to %s (%s) detected, restarting PMTU discovery", n->name, n->hostname); + n->maxmtu = MTU; + n->mtuprobes = 10; + return; + } + if(n->minmtu) n->mtuprobes = 30; else n->mtuprobes = 1; } + /* If applicable, raise the minimum supported MTU */ + if(len > n->maxmtu) len = n->maxmtu; if(n->minmtu < len) n->minmtu = len; + + /* Calculate RTT and bandwidth. + The RTT is the time between the MTU probe burst was sent and the first + reply is received. The bandwidth is measured using the time between the + arrival of the first and third probe reply. + */ + + struct timeval now, diff; + gettimeofday(&now, NULL); + timersub(&now, &n->probe_time, &diff); + n->probe_counter++; + + if(n->probe_counter == 1) { + n->rtt = diff.tv_sec + diff.tv_usec * 1e-6; + n->probe_time = now; + } else if(n->probe_counter == 3) { + n->bandwidth = 2.0 * len / (diff.tv_sec + diff.tv_usec * 1e-6); + logger(DEBUG_TRAFFIC, LOG_DEBUG, "%s (%s) RTT %.2f ms, burst bandwidth %.3f Mbit/s, rx packet loss %.2f %%", n->name, n->hostname, n->rtt * 1e3, n->bandwidth * 8e-6, n->packetloss * 1e2); + } } } @@ -206,7 +273,7 @@ static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t l return -1; #endif } - + return -1; } @@ -239,21 +306,23 @@ 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++; + n->in_bytes += packet->len; + route(n, packet); } -static bool try_mac(const node_t *n, const vpn_packet_t *inpkt) { - unsigned char hmac[EVP_MAX_MD_SIZE]; +static bool try_mac(node_t *n, const vpn_packet_t *inpkt) { + if(n->status.sptps) + return sptps_verify_datagram(&n->sptps, (char *)&inpkt->seqno, inpkt->len); - if(!n->indigest || !n->inmaclength || !n->inkey || inpkt->len < sizeof inpkt->seqno + n->inmaclength) + if(!digest_active(n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(n->indigest)) return false; - HMAC(n->indigest, n->inkey, n->inkeylength, (unsigned char *) &inpkt->seqno, inpkt->len - n->inmaclength, (unsigned char *)hmac, NULL); - - return !memcmp(hmac, (char *) &inpkt->seqno + inpkt->len - n->inmaclength, n->inmaclength); + return digest_verify(n->indigest, &inpkt->seqno, inpkt->len - digest_length(n->indigest), (const char *)&inpkt->seqno + inpkt->len - digest_length(n->indigest)); } static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { @@ -261,80 +330,83 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; int nextpkt = 0; vpn_packet_t *outpkt = pkt[0]; - int outlen, outpad; - unsigned char hmac[EVP_MAX_MD_SIZE]; - int i; + size_t outlen; - if(!n->inkey) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", - n->name, n->hostname); + if(n->status.sptps) { + if(!n->sptps.state) { + if(!n->status.waitingforkey) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but we haven't exchanged keys yet", n->name, n->hostname); + send_req_key(n); + } else { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", n->name, n->hostname); + } + return; + } + sptps_receive_data(&n->sptps, (char *)&inpkt->seqno, inpkt->len); + return; + } + + if(!cipher_active(n->incipher)) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", n->name, n->hostname); return; } /* Check packet length */ - if(inpkt->len < sizeof(inpkt->seqno) + n->inmaclength) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)", + if(inpkt->len < sizeof inpkt->seqno + digest_length(n->indigest)) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got too short packet from %s (%s)", n->name, n->hostname); return; } /* Check the message authentication code */ - if(n->indigest && n->inmaclength) { - inpkt->len -= n->inmaclength; - HMAC(n->indigest, n->inkey, n->inkeylength, - (unsigned char *) &inpkt->seqno, inpkt->len, (unsigned char *)hmac, NULL); - - if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, n->inmaclength)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)", - n->name, n->hostname); + if(digest_active(n->indigest)) { + inpkt->len -= digest_length(n->indigest); + if(!digest_verify(n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname); return; } } - /* Decrypt the packet */ - if(n->incipher) { + if(cipher_active(n->incipher)) { outpkt = pkt[nextpkt++]; + outlen = MAXSIZE; - if(!EVP_DecryptInit_ex(&n->inctx, NULL, NULL, NULL, NULL) - || !EVP_DecryptUpdate(&n->inctx, (unsigned char *) &outpkt->seqno, &outlen, - (unsigned char *) &inpkt->seqno, inpkt->len) - || !EVP_DecryptFinal_ex(&n->inctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s): %s", - n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL)); + if(!cipher_decrypt(n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname); return; } - - outpkt->len = outlen + outpad; + + outpkt->len = outlen; inpkt = outpkt; } /* Check the sequence number */ - inpkt->len -= sizeof(inpkt->seqno); + inpkt->len -= sizeof inpkt->seqno; inpkt->seqno = ntohl(inpkt->seqno); if(replaywin) { 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)", - inpkt->seqno - n->received_seqno - 1, n->name, n->hostname); + 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", - n->name, n->hostname, inpkt->seqno, n->received_seqno); + 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; } } else { - for(i = n->received_seqno + 1; i < inpkt->seqno; i++) + for(int i = n->received_seqno + 1; i < inpkt->seqno; i++) n->late[(i / 8) % replaywin] |= 1 << i % 8; } } @@ -345,9 +417,11 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { if(inpkt->seqno > n->received_seqno) n->received_seqno = inpkt->seqno; - + + n->received++; + if(n->received_seqno > MAX_SEQNO) - keyexpires = 0; + regenerate_key(); /* Decompress the packet */ @@ -357,8 +431,8 @@ 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)", - n->name, n->hostname); + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while uncompressing packet from %s (%s)", + n->name, n->hostname); return; } @@ -378,6 +452,9 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) { void receive_tcppacket(connection_t *c, const char *buffer, int len) { vpn_packet_t outpkt; + if(len > sizeof outpkt.data) + return; + outpkt.len = len; if(c->options & OPTION_TCPONLY) outpkt.priority = 0; @@ -388,34 +465,172 @@ void receive_tcppacket(connection_t *c, const char *buffer, int len) { receive_packet(c->node, &outpkt); } +static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) { + if(!n->status.validkey) { + logger(DEBUG_TRAFFIC, LOG_INFO, "No valid key known yet for %s (%s)", n->name, n->hostname); + if(!n->status.waitingforkey) + send_req_key(n); + else if(n->last_req_key + 10 < now.tv_sec) { + logger(DEBUG_ALWAYS, LOG_DEBUG, "No key from %s after 10 seconds, restarting SPTPS", n->name); + sptps_stop(&n->sptps); + n->status.waitingforkey = false; + send_req_key(n); + } + return; + } + + uint8_t type = 0; + int offset = 0; + + if(!(origpkt->data[12] | origpkt->data[13])) { + sptps_send_record(&n->sptps, PKT_PROBE, (char *)origpkt->data, origpkt->len); + return; + } + + if(routing_mode == RMODE_ROUTER) + offset = 14; + else + type = PKT_MAC; + + if(origpkt->len < offset) + return; + + vpn_packet_t outpkt; + + if(n->outcompression) { + int len = compress_packet(outpkt.data + offset, origpkt->data + offset, origpkt->len - offset, n->outcompression); + if(len < 0) { + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)", n->name, n->hostname); + } else if(len < origpkt->len - offset) { + outpkt.len = len + offset; + origpkt = &outpkt; + type |= PKT_COMPRESSED; + } + } + + sptps_send_record(&n->sptps, type, (char *)origpkt->data + offset, origpkt->len - offset); + return; +} + +static void choose_udp_address(const node_t *n, const sockaddr_t **sa, int *sock) { + /* Latest guess */ + *sa = &n->address; + *sock = n->sock; + + /* If the UDP address is confirmed, use it. */ + if(n->status.udp_confirmed) + return; + + /* Send every third packet to n->address; that could be set + to the node's reflexive UDP address discovered during key + exchange. */ + + static int x = 0; + if(++x >= 3) { + x = 0; + return; + } + + /* Otherwise, address are found in edges to this node. + So we pick a random edge and a random socket. */ + + int i = 0; + int j = rand() % n->edge_tree->count; + edge_t *candidate = NULL; + + for splay_each(edge_t, e, n->edge_tree) { + if(i++ == j) { + candidate = e->reverse; + break; + } + } + + if(candidate) { + *sa = &candidate->address; + *sock = rand() % listen_sockets; + } + + /* Make sure we have a suitable socket for the chosen address */ + if(listen_socket[*sock].sa.sa.sa_family != (*sa)->sa.sa_family) { + for(int i = 0; i < listen_sockets; i++) { + if(listen_socket[i].sa.sa.sa_family == (*sa)->sa.sa_family) { + *sock = i; + break; + } + } + } +} + +static void choose_broadcast_address(const node_t *n, const sockaddr_t **sa, int *sock) { + static sockaddr_t broadcast_ipv4 = { + .in = { + .sin_family = AF_INET, + .sin_addr.s_addr = -1, + } + }; + + static sockaddr_t broadcast_ipv6 = { + .in6 = { + .sin6_family = AF_INET6, + .sin6_addr.s6_addr[0x0] = 0xff, + .sin6_addr.s6_addr[0x1] = 0x02, + .sin6_addr.s6_addr[0xf] = 0x01, + } + }; + + *sock = rand() % listen_sockets; + + if(listen_socket[*sock].sa.sa.sa_family == AF_INET6) { + if(localdiscovery_address.sa.sa_family == AF_INET6) { + localdiscovery_address.in6.sin6_port = n->prevedge->address.in.sin_port; + *sa = &localdiscovery_address; + } else { + broadcast_ipv6.in6.sin6_port = n->prevedge->address.in.sin_port; + broadcast_ipv6.in6.sin6_scope_id = listen_socket[*sock].sa.in6.sin6_scope_id; + *sa = &broadcast_ipv6; + } + } else { + if(localdiscovery_address.sa.sa_family == AF_INET) { + localdiscovery_address.in.sin_port = n->prevedge->address.in.sin_port; + *sa = &localdiscovery_address; + } else { + broadcast_ipv4.in.sin_port = n->prevedge->address.in.sin_port; + *sa = &broadcast_ipv4; + } + } +} + static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { vpn_packet_t pkt1, pkt2; vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; vpn_packet_t *inpkt = origpkt; int nextpkt = 0; vpn_packet_t *outpkt; - int origlen; - int outlen, outpad; + int origlen = origpkt->len; + size_t outlen; #if defined(SOL_IP) && defined(IP_TOS) static int priority = 0; #endif - int origpriority; + int origpriority = origpkt->priority; 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; } + if(n->status.sptps) + return send_sptps_packet(n, origpkt); + /* Make sure we have a valid key */ if(!n->status.validkey) { - 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); - if(n->last_req_key + 10 <= now) { + if(n->last_req_key + 10 <= now.tv_sec) { send_req_key(n); - n->last_req_key = now; + n->last_req_key = now.tv_sec; } send_tcppacket(n->nexthop->connection, origpkt); @@ -424,7 +639,7 @@ 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"); @@ -436,16 +651,13 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { return; } - origlen = inpkt->len; - origpriority = inpkt->priority; - /* Compress the packet */ if(n->outcompression) { 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; } @@ -456,120 +668,221 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* Add sequence number */ inpkt->seqno = htonl(++(n->sent_seqno)); - inpkt->len += sizeof(inpkt->seqno); + inpkt->len += sizeof inpkt->seqno; /* Encrypt the packet */ - if(n->outcipher) { + if(cipher_active(n->outcipher)) { outpkt = pkt[nextpkt++]; + outlen = MAXSIZE; - if(!EVP_EncryptInit_ex(&n->outctx, NULL, NULL, NULL, NULL) - || !EVP_EncryptUpdate(&n->outctx, (unsigned char *) &outpkt->seqno, &outlen, - (unsigned char *) &inpkt->seqno, inpkt->len) - || !EVP_EncryptFinal_ex(&n->outctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) { - ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s): %s", - n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL)); + if(!cipher_encrypt(n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); goto end; } - outpkt->len = outlen + outpad; + outpkt->len = outlen; inpkt = outpkt; } /* Add the message authentication code */ - if(n->outdigest && n->outmaclength) { - HMAC(n->outdigest, n->outkey, n->outkeylength, (unsigned char *) &inpkt->seqno, - inpkt->len, (unsigned char *) &inpkt->seqno + inpkt->len, NULL); - inpkt->len += n->outmaclength; - } - - /* Determine which socket we have to use */ - - 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; - } + if(digest_active(n->outdigest)) { + if(!digest_create(n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len)) { + logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); + goto end; } + + inpkt->len += digest_length(n->outdigest); } /* Send the packet */ - struct sockaddr *sa; - socklen_t sl; + const sockaddr_t *sa; 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(origpriority == -1 && n->prevedge) + choose_broadcast_address(n, &sa, &sock); + else + choose_udp_address(n, &sa, &sock); #if defined(SOL_IP) && defined(IP_TOS) if(priorityinheritance && origpriority != priority && 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[n->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.fd, 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, sa, sl) < 0 && !sockwouldblock(sockerrno)) { + if(sendto(listen_socket[sock].udp.fd, (char *) &inpkt->seqno, inpkt->len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) { if(sockmsgsize(sockerrno)) { if(n->maxmtu >= origlen) n->maxmtu = origlen - 1; if(n->mtu >= origlen) n->mtu = origlen - 1; } else - ifdebug(TRAFFIC) logger(LOG_WARNING, "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: origpkt->len = origlen; } +bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) { + node_t *to = handle; + + /* Send it via TCP if it is a handshake packet, TCPOnly is in use, or this packet is larger than the MTU. */ + + if(type >= SPTPS_HANDSHAKE || ((myself->options | to->options) & OPTION_TCPONLY) || (type != PKT_PROBE && len > to->minmtu)) { + char buf[len * 4 / 3 + 5]; + b64encode(data, buf, len); + /* If no valid key is known yet, send the packets using ANS_KEY requests, + to ensure we get to learn the reflexive UDP address. */ + if(!to->status.validkey) + return send_request(to->nexthop->connection, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, myself->name, to->name, buf, myself->incompression); + else + return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_SPTPS, buf); + } + + /* Otherwise, send the packet via UDP */ + + const sockaddr_t *sa; + int sock; + + choose_udp_address(to, &sa, &sock); + + if(sendto(listen_socket[sock].udp.fd, data, len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) { + if(sockmsgsize(sockerrno)) { + if(to->maxmtu >= len) + to->maxmtu = len - 1; + if(to->mtu >= len) + to->mtu = len - 1; + } else { + logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending UDP SPTPS packet to %s (%s): %s", to->name, to->hostname, sockstrerror(sockerrno)); + return false; + } + } + + return true; +} + +bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t len) { + node_t *from = handle; + + if(type == SPTPS_HANDSHAKE) { + if(!from->status.validkey) { + from->status.validkey = true; + from->status.waitingforkey = false; + logger(DEBUG_META, LOG_INFO, "SPTPS key exchange with %s (%s) succesful", from->name, from->hostname); + } + return true; + } + + if(len > MTU) { + logger(DEBUG_ALWAYS, LOG_ERR, "Packet from %s (%s) larger than maximum supported size (%d > %d)", from->name, from->hostname, len, MTU); + return false; + } + + vpn_packet_t inpkt; + + if(type == PKT_PROBE) { + inpkt.len = len; + memcpy(inpkt.data, data, len); + mtu_probe_h(from, &inpkt, len); + return true; + } + + if(type & ~(PKT_COMPRESSED | PKT_MAC)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Unexpected SPTPS record type %d len %d from %s (%s)", type, len, from->name, from->hostname); + return false; + } + + /* Check if we have the headers we need */ + if(routing_mode != RMODE_ROUTER && !(type & PKT_MAC)) { + logger(DEBUG_TRAFFIC, LOG_ERR, "Received packet from %s (%s) without MAC header (maybe Mode is not set correctly)", from->name, from->hostname); + return false; + } else if(routing_mode == RMODE_ROUTER && (type & PKT_MAC)) { + logger(DEBUG_TRAFFIC, LOG_WARNING, "Received packet from %s (%s) with MAC header (maybe Mode is not set correctly)", from->name, from->hostname); + } + + int offset = (type & PKT_MAC) ? 0 : 14; + if(type & PKT_COMPRESSED) { + length_t ulen = uncompress_packet(inpkt.data + offset, (const uint8_t *)data, len, from->incompression); + if(ulen < 0) { + return false; + } else { + inpkt.len = ulen + offset; + } + if(inpkt.len > MAXSIZE) + abort(); + } else { + memcpy(inpkt.data + offset, data, len); + inpkt.len = len + offset; + } + + /* Generate the Ethernet packet type if necessary */ + if(offset) { + switch(inpkt.data[14] >> 4) { + case 4: + inpkt.data[12] = 0x08; + inpkt.data[13] = 0x00; + break; + case 6: + inpkt.data[12] = 0x86; + inpkt.data[13] = 0xDD; + break; + default: + logger(DEBUG_TRAFFIC, LOG_ERR, + "Unknown IP version %d while reading packet from %s (%s)", + inpkt.data[14] >> 4, from->name, from->hostname); + return false; + } + } + + receive_packet(from, &inpkt); + return true; +} + /* send a packet to the given vpn ip. */ -void send_packet(const node_t *n, vpn_packet_t *packet) { +void send_packet(node_t *n, vpn_packet_t *packet) { node_t *via; if(n == myself) { if(overwrite_mac) memcpy(packet->data, mymac.x, ETH_ALEN); + n->out_packets++; + n->out_bytes += packet->len; 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; } + n->out_packets++; + n->out_bytes += packet->len; + + if(n->status.sptps) { + send_sptps_packet(n, packet); + return; + } + 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)) { @@ -582,20 +895,16 @@ void send_packet(const node_t *n, vpn_packet_t *packet) { /* Broadcast a packet using the minimum spanning tree */ 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. + // 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)", + logger(DEBUG_TRAFFIC, LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)", packet->len, from->name, from->hostname); switch(broadcast_mode) { @@ -603,27 +912,21 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet) { // 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; - + for list_each(connection_t, c, connection_list) 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. + // 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 = node_udp_tree->head; node; node = node->next) { - n = node->data; - + for splay_each(node_t, n, node_tree) if(n->status.reachable && ((n->via == myself && n->nexthop == n) || n->via == n)) send_packet(n, packet); - } break; default: @@ -632,20 +935,16 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet) { } static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) { - avl_node_t *node; - edge_t *e; node_t *n = NULL; bool hard = false; static time_t last_hard_try = 0; - for(node = edge_weight_tree->head; node; node = node->next) { - e = node->data; - - if(e->to == myself) + for splay_each(edge_t, e, edge_weight_tree) { + if(!e->to->status.reachable || e->to == myself) continue; if(sockaddrcmp_noport(from, &e->address)) { - if(last_hard_try == now) + if(last_hard_try == now.tv_sec) continue; hard = true; } @@ -658,28 +957,32 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) { } if(hard) - last_hard_try = now; + last_hard_try = now.tv_sec; - last_hard_try = now; + last_hard_try = now.tv_sec; return n; } -void handle_incoming_vpn_data(int sock) { +void handle_incoming_vpn_data(void *data, int flags) { + listen_socket_t *ls = data; vpn_packet_t pkt; char *hostname; - sockaddr_t from; - socklen_t fromlen = sizeof(from); + sockaddr_t from = {{0}}; + socklen_t fromlen = sizeof from; node_t *n; + int len; - pkt.len = recvfrom(listen_socket[sock].udp, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); + len = recvfrom(ls->udp.fd, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); - if(pkt.len < 0) { + 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; } - sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */ + pkt.len = len; + + sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */ n = lookup_node_udp(&from); @@ -687,9 +990,9 @@ void handle_incoming_vpn_data(int sock) { 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; } @@ -697,7 +1000,19 @@ void handle_incoming_vpn_data(int sock) { return; } - n->sock = sock; + n->sock = ls - listen_socket; receive_udppacket(n, &pkt); } + +void handle_device_data(void *data, int flags) { + vpn_packet_t packet; + + packet.priority = 0; + + if(devops.read(&packet)) { + myself->in_packets++; + myself->in_bytes += packet.len; + route(myself, &packet); + } +}