X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet_packet.c;h=ae5a8402a7af159ad3873b877854c2b286a0c485;hp=7c51ad6388989b79ba4c30ac67173e401eab158c;hb=56aad1bb486675ff9aba31418708cc179eea0381;hpb=5eca9520d93bced1275d45e5e2a933d69354cd6d diff --git a/src/net_packet.c b/src/net_packet.c index 7c51ad63..ae5a8402 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) 1998-2002 Ivo Timmermans , - 2000-2002 Guus Sliepen + Copyright (C) 1998-2003 Ivo Timmermans , + 2000-2003 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,113 +17,209 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: net_packet.c,v 1.1.2.24 2002/09/15 14:55:53 guus Exp $ + $Id: net_packet.c,v 1.1.2.49 2003/12/27 16:32:52 guus Exp $ */ -#include "config.h" - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -/* SunOS really wants sys/socket.h BEFORE net/if.h, - and FreeBSD wants these lines below the rest. */ -#include -#include -#include -#ifdef HAVE_NETINET_IN_SYSTM_H -#include -#endif -#ifdef HAVE_NETINET_IP_H -#include -#endif -#ifdef HAVE_NETINET_TCP_H -#include -#endif +#include "system.h" #include +#include #include #include #include #include +#include -#include -#include -#include -#include - +#include "avl_tree.h" #include "conf.h" #include "connection.h" -#include "meta.h" +#include "device.h" +#include "ethernet.h" +#include "event.h" +#include "graph.h" +#include "list.h" +#include "logger.h" #include "net.h" #include "netutl.h" -#include "process.h" #include "protocol.h" -#include "subnet.h" -#include "graph.h" #include "process.h" #include "route.h" -#include "device.h" -#include "event.h" +#include "utils.h" +#include "xalloc.h" -#include "system.h" +#ifdef WSAEMSGSIZE +#define EMSGSIZE WSAEMSGSIZE +#endif int keylifetime = 0; int keyexpires = 0; +bool strictsource = true; +EVP_CIPHER_CTX packet_ctx; +static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS]; + +static void send_udppacket(node_t *, vpn_packet_t *); #define MAX_SEQNO 1073741824 +void send_mtu_probe(node_t *n) +{ + vpn_packet_t packet; + int len, i; + + cp(); + + n->mtuprobes++; + n->mtuevent = NULL; + + if(n->mtuprobes >= 10 && !n->minmtu) { + ifdebug(TRAFFIC) logger(LOG_INFO, _("No response to MTU probes from %s (%s)"), n->name, n->hostname); + return; + } + + for(i = 0; i < 3; i++) { + if(n->mtuprobes >= 30 || n->minmtu >= n->maxmtu) { + 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); + return; + } + + len = n->minmtu + 1 + random() % (n->maxmtu - n->minmtu); + if(len < 64) + len = 64; + + memset(packet.data, 0, 14); + RAND_pseudo_bytes(packet.data + 14, len - 14); + packet.len = len; + + ifdebug(TRAFFIC) logger(LOG_INFO, _("Sending MTU probe length %d to %s (%s)"), len, n->name, n->hostname); + + send_udppacket(n, &packet); + } + + n->mtuevent = xmalloc(sizeof(*n->mtuevent)); + n->mtuevent->handler = (event_handler_t)send_mtu_probe; + n->mtuevent->data = n; + n->mtuevent->time = now + 1; + event_add(n->mtuevent); +} + +void mtu_probe_h(node_t *n, vpn_packet_t *packet) { + ifdebug(TRAFFIC) logger(LOG_INFO, _("Got MTU probe length %d from %s (%s)"), packet->len, n->name, n->hostname); + + if(!packet->data[0]) { + packet->data[0] = 1; + send_packet(n, packet); + } else { + if(n->minmtu < packet->len) + n->minmtu = packet->len; + } +} + +static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) +{ + if(level == 10) { + lzo_uint lzolen = MAXSIZE; + lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem); + return lzolen; + } else if(level < 10) { + unsigned long destlen = MAXSIZE; + if(compress2(dest, &destlen, source, len, level) == Z_OK) + return destlen; + else + return -1; + } else { + lzo_uint lzolen = MAXSIZE; + lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem); + return lzolen; + } + + return -1; +} + +static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) +{ + if(level > 9) { + lzo_uint lzolen = MAXSIZE; + if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK) + return lzolen; + else + return -1; + } else { + unsigned long destlen = MAXSIZE; + if(uncompress(dest, &destlen, source, len) == Z_OK) + return destlen; + else + return -1; + } + + return -1; +} + /* VPN packet I/O */ -void receive_udppacket(node_t *n, vpn_packet_t *inpkt) +static void receive_packet(node_t *n, vpn_packet_t *packet) { - vpn_packet_t pkt1, pkt2; - vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; - int nextpkt = 0; - vpn_packet_t *outpkt = pkt[0]; - int outlen, outpad; - long int complen = MTU + 12; - EVP_CIPHER_CTX ctx; + cp(); + + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"), + packet->len, n->name, n->hostname); + + route(n, packet); +} + +static bool authenticate_udppacket(node_t *n, vpn_packet_t *inpkt) { char hmac[EVP_MAX_MD_SIZE]; - cp(); + if(inpkt->len < sizeof(inpkt->seqno) + (myself->digest ? myself->maclength : 0)) + return false; /* Check the message authentication code */ if(myself->digest && myself->maclength) { - inpkt->len -= myself->maclength; HMAC(myself->digest, myself->key, myself->keylength, - (char *) &inpkt->seqno, inpkt->len, hmac, NULL); + (char *) &inpkt->seqno, inpkt->len - myself->maclength, hmac, NULL); + + if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len - myself->maclength, myself->maclength)) + return false; + } + + return true; +} + +static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) +{ + vpn_packet_t pkt1, pkt2; + vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; + int nextpkt = 0; + vpn_packet_t *outpkt = pkt[0]; + int outlen, outpad; + int i; - if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"), + cp(); + + if(!authenticate_udppacket(n, inpkt)) { + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"), n->name, n->hostname); - return; - } + return; } + inpkt->len -= myself->digest ? myself->maclength : 0; + /* Decrypt the packet */ if(myself->cipher) { outpkt = pkt[nextpkt++]; - EVP_DecryptInit(&ctx, myself->cipher, myself->key, - myself->key + myself->cipher->key_len); - EVP_DecryptUpdate(&ctx, (char *) &outpkt->seqno, &outlen, - (char *) &inpkt->seqno, inpkt->len); - EVP_DecryptFinal(&ctx, (char *) &outpkt->seqno + outlen, &outpad); - + if(!EVP_DecryptInit_ex(&packet_ctx, NULL, NULL, NULL, NULL) + || !EVP_DecryptUpdate(&packet_ctx, (char *) &outpkt->seqno, &outlen, + (char *) &inpkt->seqno, inpkt->len) + || !EVP_DecryptFinal_ex(&packet_ctx, (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)); + return; + } + outpkt->len = outlen + outpad; inpkt = outpkt; } @@ -133,16 +229,25 @@ void receive_udppacket(node_t *n, vpn_packet_t *inpkt) inpkt->len -= sizeof(inpkt->seqno); inpkt->seqno = ntohl(inpkt->seqno); - if(inpkt->seqno <= n->received_seqno) { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, - _("Got late or replayed packet from %s (%s), seqno %d"), - n->name, n->hostname, inpkt->seqno); - return; + if(inpkt->seqno != n->received_seqno + 1) { + if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) { + logger(LOG_WARNING, _("Lost %d packets from %s (%s)"), + inpkt->seqno - n->received_seqno - 1, n->name, n->hostname); + + memset(n->late, 0, sizeof(n->late)); + } else if (inpkt->seqno <= n->received_seqno) { + if(inpkt->seqno <= n->received_seqno - sizeof(n->late) * 8 || !(n->late[(inpkt->seqno / 8) % sizeof(n->late)] & (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); + } else + for(i = n->received_seqno + 1; i < inpkt->seqno; i++) + n->late[(inpkt->seqno / 8) % sizeof(n->late)] |= 1 << i % 8; + } } - + n->received_seqno = inpkt->seqno; - + n->late[(n->received_seqno / 8) % sizeof(n->late)] &= ~(1 << n->received_seqno % 8); + if(n->received_seqno > MAX_SEQNO) keyexpires = 0; @@ -151,17 +256,22 @@ void receive_udppacket(node_t *n, vpn_packet_t *inpkt) if(myself->compression) { outpkt = pkt[nextpkt++]; - if(uncompress(outpkt->data, &complen, inpkt->data, inpkt->len) != Z_OK) { - syslog(LOG_ERR, _("Error while uncompressing packet from %s (%s)"), - n->name, n->hostname); + if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, myself->compression)) < 0) { + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while uncompressing packet from %s (%s)"), + n->name, n->hostname); return; } - outpkt->len = complen; inpkt = outpkt; } - receive_packet(n, inpkt); + if(n->connection) + n->connection->last_ping_time = now; + + if(!inpkt->data[12] && !inpkt->data[13]) + mtu_probe_h(n, inpkt); + else + receive_packet(n, inpkt); } void receive_tcppacket(connection_t *c, char *buffer, int len) @@ -176,18 +286,7 @@ void receive_tcppacket(connection_t *c, char *buffer, int len) receive_packet(c->node, &outpkt); } -void receive_packet(node_t *n, vpn_packet_t *packet) -{ - cp(); - - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"), - packet->len, n->name, n->hostname); - - route_incoming(n, packet); -} - -void send_udppacket(node_t *n, vpn_packet_t *inpkt) +static void send_udppacket(node_t *n, vpn_packet_t *inpkt) { vpn_packet_t pkt1, pkt2; vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 }; @@ -195,8 +294,6 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) vpn_packet_t *outpkt; int origlen; int outlen, outpad; - long int complen = MTU + 12; - EVP_CIPHER_CTX ctx; vpn_packet_t *copy; static int priority = 0; int origpriority; @@ -207,15 +304,13 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) /* Make sure we have a valid key */ if(!n->status.validkey) { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_INFO, + ifdebug(TRAFFIC) logger(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"), n->name, n->hostname); /* Since packet is on the stack of handle_tap_input(), we have to make a copy of it first. */ - copy = xmalloc(sizeof(vpn_packet_t)); - memcpy(copy, inpkt, sizeof(vpn_packet_t)); + *(copy = xmalloc(sizeof(*copy))) = *inpkt; list_insert_tail(n->queue, copy); @@ -225,7 +320,7 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) if(!n->status.waitingforkey) send_req_key(n->nexthop->connection, myself, n); - n->status.waitingforkey = 1; + n->status.waitingforkey = true; return; } @@ -238,15 +333,12 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) if(n->compression) { outpkt = pkt[nextpkt++]; - if(compress2 - (outpkt->data, &complen, inpkt->data, inpkt->len, - n->compression) != Z_OK) { - syslog(LOG_ERR, _("Error while compressing packet to %s (%s)"), + if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->compression)) < 0) { + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while compressing packet to %s (%s)"), n->name, n->hostname); return; } - outpkt->len = complen; inpkt = outpkt; } @@ -260,10 +352,14 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) if(n->cipher) { outpkt = pkt[nextpkt++]; - EVP_EncryptInit(&ctx, n->cipher, n->key, n->key + n->cipher->key_len); - EVP_EncryptUpdate(&ctx, (char *) &outpkt->seqno, &outlen, - (char *) &inpkt->seqno, inpkt->len); - EVP_EncryptFinal(&ctx, (char *) &outpkt->seqno + outlen, &outpad); + if(!EVP_EncryptInit_ex(&n->packet_ctx, NULL, NULL, NULL, NULL) + || !EVP_EncryptUpdate(&n->packet_ctx, (char *) &outpkt->seqno, &outlen, + (char *) &inpkt->seqno, inpkt->len) + || !EVP_EncryptFinal_ex(&n->packet_ctx, (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)); + goto end; + } outpkt->len = outlen + outpad; inpkt = outpkt; @@ -292,80 +388,78 @@ void send_udppacket(node_t *n, vpn_packet_t *inpkt) if(priorityinheritance && origpriority != priority && listen_socket[sock].sa.sa.sa_family == AF_INET) { priority = origpriority; - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, _("Setting outgoing packet priority to %d"), - priority); - if(setsockopt(sock, SOL_IP, IP_TOS, &priority, sizeof(priority))) /* SO_PRIORITY doesn't seem to work */ - syslog(LOG_ERR, _("System call `%s' failed: %s"), "setsockopt", - strerror(errno)); + 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)); } #endif if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) { - syslog(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, - n->hostname, strerror(errno)); - return; + if(errno == EMSGSIZE) { + 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, strerror(errno)); } +end: inpkt->len = origlen; } /* send a packet to the given vpn ip. */ -void send_packet(node_t *n, vpn_packet_t *packet) +void send_packet(const node_t *n, vpn_packet_t *packet) { node_t *via; cp(); - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), - packet->len, n->name, n->hostname); - if(n == myself) { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_NOTICE, _("Packet is looping back to us!")); - + if(overwrite_mac) + memcpy(packet->data, mymac.x, ETH_ALEN); + write_packet(packet); return; } + ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), + packet->len, n->name, n->hostname); + if(!n->status.reachable) { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_INFO, _("Node %s (%s) is not reachable"), + ifdebug(TRAFFIC) logger(LOG_INFO, _("Node %s (%s) is not reachable"), n->name, n->hostname); - return; } via = (n->via == myself) ? n->nexthop : n->via; - if(via != n && debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_ERR, _("Sending packet to %s via %s (%s)"), + if(via != n) + ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet to %s via %s (%s)"), n->name, via->name, n->via->hostname); if((myself->options | via->options) & OPTION_TCPONLY) { - if(send_tcppacket(via->connection, packet)) - terminate_connection(via->connection, 1); + if(!send_tcppacket(via->connection, packet)) + terminate_connection(via->connection, true); } else send_udppacket(via, packet); } /* Broadcast a packet using the minimum spanning tree */ -void broadcast_packet(node_t *from, vpn_packet_t *packet) +void broadcast_packet(const node_t *from, vpn_packet_t *packet) { avl_node_t *node; connection_t *c; cp(); - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"), + ifdebug(TRAFFIC) logger(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"), packet->len, from->name, from->hostname); for(node = connection_tree->head; node; node = node->next) { - c = (connection_t *) node->data; + c = node->data; if(c->status.active && c->status.mst && c != from->nexthop->connection) send_packet(c->node, packet); @@ -378,12 +472,11 @@ void flush_queue(node_t *n) cp(); - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_INFO, _("Flushing queue for %s (%s)"), n->name, n->hostname); + ifdebug(TRAFFIC) logger(LOG_INFO, _("Flushing queue for %s (%s)"), n->name, n->hostname); for(node = n->queue->head; node; node = next) { next = node->next; - send_udppacket(n, (vpn_packet_t *) node->data); + send_udppacket(n, node->data); list_delete_node(n->queue, node); } } @@ -391,30 +484,18 @@ void flush_queue(node_t *n) void handle_incoming_vpn_data(int sock) { vpn_packet_t pkt; - int x, l = sizeof(x); char *hostname; sockaddr_t from; socklen_t fromlen = sizeof(from); node_t *n; + static time_t lasttime = 0; cp(); - if(getsockopt(sock, SOL_SOCKET, SO_ERROR, &x, &l) < 0) { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%s"), - __FILE__, __LINE__, sock, strerror(errno)); - cp_trace(); - exit(1); - } - - if(x) { - syslog(LOG_ERR, _("Incoming data socket error: %s"), strerror(x)); - return; - } - pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); - if(pkt.len <= 0) { - syslog(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno)); + if(pkt.len < 0) { + logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno)); return; } @@ -422,16 +503,28 @@ void handle_incoming_vpn_data(int sock) n = lookup_node_udp(&from); + if(!n && !strictsource && myself->digest && myself->maclength && lasttime != now) { + avl_node_t *node; + + lasttime = now; + + for(node = node_tree->head; node; node = node->next) { + n = node->data; + + if(authenticate_udppacket(n, &pkt)) { + update_node_address(n, &from); + logger(LOG_DEBUG, _("Updated address of node %s to %s"), n->name, n->hostname); + break; + } + } + } + if(!n) { hostname = sockaddr2hostname(&from); - syslog(LOG_WARNING, _("Received UDP packet from unknown source %s"), - hostname); + logger(LOG_WARNING, _("Received UDP packet from unknown source %s"), hostname); free(hostname); return; } - if(n->connection) - n->connection->last_ping_time = now; - receive_udppacket(n, &pkt); }