X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet_packet.c;h=ed49b0b2add2020cc0e62ec414e009ee72b04e70;hp=aa5bea3415750f07bd3ded17b7563bc92d28a353;hb=0077cfaae112b63d6af6aa1e5d079cebdde84b74;hpb=b4c913aaa926d80a72aeb97459f84f992b65d1ed diff --git a/src/net_packet.c b/src/net_packet.c index aa5bea34..ed49b0b2 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) 1998-2003 Ivo Timmermans , - 2000-2003 Guus Sliepen + Copyright (C) 1998-2004 Ivo Timmermans , + 2000-2004 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 @@ -17,12 +17,13 @@ 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 1.1.2.37 2003/08/08 19:42:35 guus Exp $ + $Id$ */ #include "system.h" #include +#include #include #include #include @@ -34,6 +35,7 @@ #include "conf.h" #include "connection.h" #include "device.h" +#include "ethernet.h" #include "event.h" #include "graph.h" #include "list.h" @@ -46,14 +48,73 @@ #include "utils.h" #include "xalloc.h" +#ifdef WSAEMSGSIZE +#define EMSGSIZE WSAEMSGSIZE +#endif + int keylifetime = 0; int keyexpires = 0; 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) { @@ -103,7 +164,7 @@ static void receive_packet(node_t *n, vpn_packet_t *packet) ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"), packet->len, n->name, n->hostname); - route_incoming(n, packet); + route(n, packet); } static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) @@ -118,6 +179,14 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) cp(); + /* Check packet length */ + + if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) { + ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"), + n->name, n->hostname); + return; + } + /* Check the message authentication code */ if(myself->digest && myself->maclength) { @@ -137,12 +206,14 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) if(myself->cipher) { outpkt = pkt[nextpkt++]; -// EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, myself->key, -// myself->key + myself->cipher->key_len); - 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); + 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; @@ -160,17 +231,21 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) 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))) { + if((n->received_seqno >= sizeof(n->late) * 8 && 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; + return; + } + } else { + for(i = n->received_seqno + 1; i < inpkt->seqno; i++) + n->late[(i / 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); + n->late[(inpkt->seqno / 8) % sizeof(n->late)] &= ~(1 << inpkt->seqno % 8); + + if(inpkt->seqno > n->received_seqno) + n->received_seqno = inpkt->seqno; if(n->received_seqno > MAX_SEQNO) keyexpires = 0; @@ -181,15 +256,21 @@ 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, myself->compression)) < 0) { - logger(LOG_ERR, _("Error while uncompressing packet from %s (%s)"), - n->name, n->hostname); + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while uncompressing packet from %s (%s)"), + n->name, n->hostname); return; } 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) @@ -228,8 +309,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt) /* 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); @@ -253,7 +333,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt) outpkt = pkt[nextpkt++]; if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->compression)) < 0) { - logger(LOG_ERR, _("Error while compressing packet to %s (%s)"), + ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while compressing packet to %s (%s)"), n->name, n->hostname); return; } @@ -271,11 +351,14 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt) if(n->cipher) { outpkt = pkt[nextpkt++]; -// EVP_EncryptInit_ex(&packet_ctx, n->cipher, NULL, n->key, n->key + n->cipher->key_len); - 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); + 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; @@ -311,10 +394,16 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt) #endif if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) { - logger(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; } @@ -327,14 +416,16 @@ void send_packet(const node_t *n, vpn_packet_t *packet) cp(); - ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), - packet->len, n->name, n->hostname); - if(n == myself) { - ifdebug(TRAFFIC) logger(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) { ifdebug(TRAFFIC) logger(LOG_INFO, _("Node %s (%s) is not reachable"), n->name, n->hostname); @@ -366,8 +457,14 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet) ifdebug(TRAFFIC) logger(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"), packet->len, from->name, from->hostname); + if(from != myself) { + if(overwrite_mac) + memcpy(packet->data, mymac.x, ETH_ALEN); + write_packet(packet); + } + 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); @@ -384,7 +481,7 @@ void flush_queue(node_t *n) 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); } } @@ -392,7 +489,6 @@ 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); @@ -400,21 +496,9 @@ void handle_incoming_vpn_data(int sock) cp(); - if(getsockopt(sock, SOL_SOCKET, SO_ERROR, &x, &l) < 0) { - logger(LOG_ERR, _("This is a bug: %s:%d: %d:%s"), - __FILE__, __LINE__, sock, strerror(errno)); - cp_trace(); - exit(1); - } - - if(x) { - logger(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) { + if(pkt.len < 0) { logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno)); return; } @@ -431,8 +515,5 @@ void handle_incoming_vpn_data(int sock) return; } - if(n->connection) - n->connection->last_ping_time = now; - receive_udppacket(n, &pkt); }