X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet_packet.c;h=ae5a8402a7af159ad3873b877854c2b286a0c485;hp=c0bd24767ad5fefae59adedeafa15fa0d6aeb5f2;hb=56aad1bb486675ff9aba31418708cc179eea0381;hpb=5db596c6844169f1eb5f804b72abe99d067aaa5a diff --git a/src/net_packet.c b/src/net_packet.c index c0bd2476..ae5a8402 100644 --- a/src/net_packet.c +++ b/src/net_packet.c @@ -17,39 +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 1.1.2.33 2003/07/12 17:41:46 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 -/* 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 @@ -57,36 +31,91 @@ #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 "logger.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) { @@ -136,7 +165,26 @@ 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 bool authenticate_udppacket(node_t *n, vpn_packet_t *inpkt) { + char hmac[EVP_MAX_MD_SIZE]; + + if(inpkt->len < sizeof(inpkt->seqno) + (myself->digest ? myself->maclength : 0)) + return false; + + /* Check the message authentication code */ + + if(myself->digest && myself->maclength) { + HMAC(myself->digest, myself->key, myself->keylength, + (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) @@ -146,36 +194,31 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) int nextpkt = 0; vpn_packet_t *outpkt = pkt[0]; int outlen, outpad; - char hmac[EVP_MAX_MD_SIZE]; int i; cp(); - /* 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); - - if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) { - ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"), + 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_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; @@ -214,15 +257,21 @@ 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) @@ -261,8 +310,7 @@ 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); @@ -272,7 +320,7 @@ static 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; } @@ -286,7 +334,7 @@ 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; } @@ -304,11 +352,14 @@ 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; @@ -339,37 +390,43 @@ static void send_udppacket(node_t *n, vpn_packet_t *inpkt) 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(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) { - 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; } /* 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(); - 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); @@ -383,15 +440,15 @@ void send_packet(node_t *n, vpn_packet_t *packet) 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; @@ -402,7 +459,7 @@ void broadcast_packet(node_t *from, vpn_packet_t *packet) 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); @@ -419,7 +476,7 @@ 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); } } @@ -427,29 +484,17 @@ 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) { - 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; } @@ -458,16 +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); - logger(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); }