git.tinc-vpn.org Git - tinc/blob - src/net_packet.c

   1 /*
   2     net_packet.c -- Handles in- and outgoing VPN packets
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2010 Guus Sliepen <guus@tinc-vpn.org>
   5                   2010      Timothy Redaelli <timothy@redaelli.eu>
   6                   2010      Brandon Black <blblack@gmail.com>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License along
  19     with this program; if not, write to the Free Software Foundation, Inc.,
  20     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21 */
  22
  23 #include "system.h"
  24
  25 #include <openssl/rand.h>
  26 #include <openssl/err.h>
  27 #include <openssl/evp.h>
  28 #include <openssl/pem.h>
  29 #include <openssl/hmac.h>
  30
  31 #ifdef HAVE_ZLIB
  32 #include <zlib.h>
  33 #endif
  34
  35 #ifdef HAVE_LZO
  36 #include LZO1X_H
  37 #endif
  38
  39 #include "splay_tree.h"
  40 #include "cipher.h"
  41 #include "conf.h"
  42 #include "connection.h"
  43 #include "crypto.h"
  44 #include "digest.h"
  45 #include "device.h"
  46 #include "ethernet.h"
  47 #include "graph.h"
  48 #include "list.h"
  49 #include "logger.h"
  50 #include "net.h"
  51 #include "netutl.h"
  52 #include "protocol.h"
  53 #include "process.h"
  54 #include "route.h"
  55 #include "utils.h"
  56 #include "xalloc.h"
  57
  58 int keylifetime = 0;
  59 int keyexpires = 0;
  60 #ifdef HAVE_LZO
  61 static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
  62 #endif
  63
  64 static void send_udppacket(node_t *, vpn_packet_t *);
  65
  66 unsigned replaywin = 16;
  67
  68 #define MAX_SEQNO 1073741824
  69
  70 // mtuprobes == 1..30: initial discovery, send bursts with 1 second interval
  71 // mtuprobes ==    31: sleep pinginterval seconds
  72 // mtuprobes ==    32: send 1 burst, sleep pingtimeout second
  73 // mtuprobes ==    33: no response from other side, restart PMTU discovery process
  74
  75 static void send_mtu_probe_handler(int fd, short events, void *data) {
  76         node_t *n = data;
  77         vpn_packet_t packet;
  78         int len, i;
  79         int timeout = 1;
  80
  81         n->mtuprobes++;
  82
  83         if(!n->status.reachable || !n->status.validkey) {
  84                 ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname);
  85                 n->mtuprobes = 0;
  86                 return;
  87         }
  88
  89         if(n->mtuprobes > 32) {
  90                 ifdebug(TRAFFIC) logger(LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname);
  91                 n->mtuprobes = 1;
  92                 n->minmtu = 0;
  93                 n->maxmtu = MTU;
  94         }
  95
  96         if(n->mtuprobes >= 10 && !n->minmtu) {
  97                 ifdebug(TRAFFIC) logger(LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname);
  98                 n->mtuprobes = 0;
  99                 return;
 100         }
 101
 102         if(n->mtuprobes == 30 || (n->mtuprobes < 30 && n->minmtu >= n->maxmtu)) {
 103                 if(n->minmtu > n->maxmtu)
 104                         n->minmtu = n->maxmtu;
 105                 else
 106                         n->maxmtu = n->minmtu;
 107                 n->mtu = n->minmtu;
 108                 ifdebug(TRAFFIC) logger(LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
 109                 n->mtuprobes = 31;
 110         }
 111
 112         if(n->mtuprobes == 31) {
 113                 timeout = pinginterval;
 114                 goto end;
 115         } else if(n->mtuprobes == 32) {
 116                 timeout = pingtimeout;
 117         }
 118
 119         for(i = 0; i < 3; i++) {
 120                 if(n->maxmtu <= n->minmtu)
 121                         len = n->maxmtu;
 122                 else
 123                         len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
 124
 125                 if(len < 64)
 126                         len = 64;
 127
 128                 memset(packet.data, 0, 14);
 129                 randomize(packet.data + 14, len - 14);
 130                 packet.len = len;
 131                 packet.priority = 0;
 132
 133                 ifdebug(TRAFFIC) logger(LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname);
 134
 135                 send_udppacket(n, &packet);
 136         }
 137
 138 end:
 139         event_add(&n->mtuevent, &(struct timeval){timeout, 0});
 140 }
 141
 142 void send_mtu_probe(node_t *n) {
 143         if(!timeout_initialized(&n->mtuevent))
 144                 timeout_set(&n->mtuevent, send_mtu_probe_handler, n);
 145         send_mtu_probe_handler(0, 0, n);
 146 }
 147
 148 void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 149         ifdebug(TRAFFIC) logger(LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname);
 150
 151         if(!packet->data[0]) {
 152                 packet->data[0] = 1;
 153                 send_udppacket(n, packet);
 154         } else {
 155                 if(len > n->maxmtu)
 156                         len = n->maxmtu;
 157                 if(n->minmtu < len)
 158                         n->minmtu = len;
 159                 if(n->mtuprobes > 30)
 160                         n->mtuprobes = 30;
 161         }
 162 }
 163
 164 static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 165         if(level == 0) {
 166                 memcpy(dest, source, len);
 167                 return len;
 168         } else if(level == 10) {
 169 #ifdef HAVE_LZO
 170                 lzo_uint lzolen = MAXSIZE;
 171                 lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
 172                 return lzolen;
 173 #else
 174                 return -1;
 175 #endif
 176         } else if(level < 10) {
 177 #ifdef HAVE_ZLIB
 178                 unsigned long destlen = MAXSIZE;
 179                 if(compress2(dest, &destlen, source, len, level) == Z_OK)
 180                         return destlen;
 181                 else
 182 #endif
 183                         return -1;
 184         } else {
 185 #ifdef HAVE_LZO
 186                 lzo_uint lzolen = MAXSIZE;
 187                 lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
 188                 return lzolen;
 189 #else
 190                 return -1;
 191 #endif
 192         }
 193
 194         return -1;
 195 }
 196
 197 static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 198         if(level == 0) {
 199                 memcpy(dest, source, len);
 200                 return len;
 201         } else if(level > 9) {
 202 #ifdef HAVE_LZO
 203                 lzo_uint lzolen = MAXSIZE;
 204                 if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
 205                         return lzolen;
 206                 else
 207 #endif
 208                         return -1;
 209         }
 210 #ifdef HAVE_ZLIB
 211         else {
 212                 unsigned long destlen = MAXSIZE;
 213                 if(uncompress(dest, &destlen, source, len) == Z_OK)
 214                         return destlen;
 215                 else
 216                         return -1;
 217         }
 218 #endif
 219
 220         return -1;
 221 }
 222
 223 /* VPN packet I/O */
 224
 225 static void receive_packet(node_t *n, vpn_packet_t *packet) {
 226         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Received packet of %d bytes from %s (%s)",
 227                            packet->len, n->name, n->hostname);
 228
 229         route(n, packet);
 230 }
 231
 232 static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
 233         if(!digest_active(&n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest))
 234                 return false;
 235
 236         return digest_verify(&n->indigest, &inpkt->seqno, inpkt->len - n->indigest.maclength, (const char *)&inpkt->seqno + inpkt->len - n->indigest.maclength);
 237 }
 238
 239 static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 240         vpn_packet_t pkt1, pkt2;
 241         vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 242         int nextpkt = 0;
 243         vpn_packet_t *outpkt = pkt[0];
 244         size_t outlen;
 245         int i;
 246
 247         if(!cipher_active(&n->incipher)) {
 248                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
 249                                         n->name, n->hostname);
 250                 return;
 251         }
 252
 253         /* Check packet length */
 254
 255         if(inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest)) {
 256                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)",
 257                                         n->name, n->hostname);
 258                 return;
 259         }
 260
 261         /* Check the message authentication code */
 262
 263         if(digest_active(&n->indigest)) {
 264                 inpkt->len -= n->indigest.maclength;
 265                 if(!digest_verify(&n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) {
 266                         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname);
 267                         return;
 268                 }
 269         }
 270         /* Decrypt the packet */
 271
 272         if(cipher_active(&n->incipher)) {
 273                 outpkt = pkt[nextpkt++];
 274                 outlen = MAXSIZE;
 275
 276                 if(!cipher_decrypt(&n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
 277                         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname);
 278                         return;
 279                 }
 280
 281                 outpkt->len = outlen;
 282                 inpkt = outpkt;
 283         }
 284
 285         /* Check the sequence number */
 286
 287         inpkt->len -= sizeof inpkt->seqno;
 288         inpkt->seqno = ntohl(inpkt->seqno);
 289
 290         if(replaywin) {
 291                 if(inpkt->seqno != n->received_seqno + 1) {
 292                         if(inpkt->seqno >= n->received_seqno + replaywin * 8) {
 293                                 if(n->farfuture++ < replaywin >> 2) {
 294                                         logger(LOG_WARNING, "Packet from %s (%s) is %d seqs in the future, dropped (%u)",
 295                                                 n->name, n->hostname, inpkt->seqno - n->received_seqno - 1, n->farfuture);
 296                                         return;
 297                                 }
 298                                 logger(LOG_WARNING, "Lost %d packets from %s (%s)",
 299                                                 inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
 300                                 memset(n->late, 0, replaywin);
 301                         } else if (inpkt->seqno <= n->received_seqno) {
 302                                 if((n->received_seqno >= replaywin * 8 && inpkt->seqno <= n->received_seqno - replaywin * 8) || !(n->late[(inpkt->seqno / 8) % replaywin] & (1 << inpkt->seqno % 8))) {
 303                                         logger(LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d",
 304                                                 n->name, n->hostname, inpkt->seqno, n->received_seqno);
 305                                         return;
 306                                 }
 307                         } else {
 308                                 for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
 309                                         n->late[(i / 8) % replaywin] |= 1 << i % 8;
 310                         }
 311                 }
 312
 313                 n->farfuture = 0;
 314                 n->late[(inpkt->seqno / 8) % replaywin] &= ~(1 << inpkt->seqno % 8);
 315         }
 316
 317         if(inpkt->seqno > n->received_seqno)
 318                 n->received_seqno = inpkt->seqno;
 319
 320         if(n->received_seqno > MAX_SEQNO)
 321                 regenerate_key();
 322
 323         /* Decompress the packet */
 324
 325         length_t origlen = inpkt->len;
 326
 327         if(n->incompression) {
 328                 outpkt = pkt[nextpkt++];
 329
 330                 if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression)) < 0) {
 331                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while uncompressing packet from %s (%s)",
 332                                                  n->name, n->hostname);
 333                         return;
 334                 }
 335
 336                 inpkt = outpkt;
 337
 338                 origlen -= MTU/64 + 20;
 339         }
 340
 341         inpkt->priority = 0;
 342
 343         if(!inpkt->data[12] && !inpkt->data[13])
 344                 mtu_probe_h(n, inpkt, origlen);
 345         else
 346                 receive_packet(n, inpkt);
 347 }
 348
 349 void receive_tcppacket(connection_t *c, char *buffer, int len) {
 350         vpn_packet_t outpkt;
 351
 352         outpkt.len = len;
 353         if(c->options & OPTION_TCPONLY)
 354                 outpkt.priority = 0;
 355         else
 356                 outpkt.priority = -1;
 357         memcpy(outpkt.data, buffer, len);
 358
 359         receive_packet(c->node, &outpkt);
 360 }
 361
 362 static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 363         vpn_packet_t pkt1, pkt2;
 364         vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 365         vpn_packet_t *inpkt = origpkt;
 366         int nextpkt = 0;
 367         vpn_packet_t *outpkt;
 368         int origlen;
 369         size_t outlen;
 370 #if defined(SOL_IP) && defined(IP_TOS)
 371         static int priority = 0;
 372 #endif
 373         int origpriority;
 374         int sock;
 375
 376         if(!n->status.reachable) {
 377                 ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname);
 378                 return;
 379         }
 380
 381         /* Make sure we have a valid key */
 382
 383         if(!n->status.validkey) {
 384                 time_t now = time(NULL);
 385
 386                 ifdebug(TRAFFIC) logger(LOG_INFO,
 387                                    "No valid key known yet for %s (%s), forwarding via TCP",
 388                                    n->name, n->hostname);
 389
 390                 if(n->last_req_key + 10 < now) {
 391                         send_req_key(n);
 392                         n->last_req_key = now;
 393                 }
 394
 395                 send_tcppacket(n->nexthop->connection, origpkt);
 396
 397                 return;
 398         }
 399
 400         if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
 401                 ifdebug(TRAFFIC) logger(LOG_INFO,
 402                                 "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
 403                                 n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
 404
 405                 if(n != n->nexthop)
 406                         send_packet(n->nexthop, origpkt);
 407                 else
 408                         send_tcppacket(n->nexthop->connection, origpkt);
 409
 410                 return;
 411         }
 412
 413         origlen = inpkt->len;
 414         origpriority = inpkt->priority;
 415
 416         /* Compress the packet */
 417
 418         if(n->outcompression) {
 419                 outpkt = pkt[nextpkt++];
 420
 421                 if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression)) < 0) {
 422                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while compressing packet to %s (%s)",
 423                                    n->name, n->hostname);
 424                         return;
 425                 }
 426
 427                 inpkt = outpkt;
 428         }
 429
 430         /* Add sequence number */
 431
 432         inpkt->seqno = htonl(++(n->sent_seqno));
 433         inpkt->len += sizeof inpkt->seqno;
 434
 435         /* Encrypt the packet */
 436
 437         if(cipher_active(&n->outcipher)) {
 438                 outpkt = pkt[nextpkt++];
 439                 outlen = MAXSIZE;
 440
 441                 if(!cipher_encrypt(&n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
 442                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname);
 443                         goto end;
 444                 }
 445
 446                 outpkt->len = outlen;
 447                 inpkt = outpkt;
 448         }
 449
 450         /* Add the message authentication code */
 451
 452         if(digest_active(&n->outdigest)) {
 453                 digest_create(&n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len);
 454                 inpkt->len += digest_length(&n->outdigest);
 455         }
 456
 457         /* Determine which socket we have to use */
 458
 459         for(sock = 0; sock < listen_sockets; sock++)
 460                 if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family)
 461                         break;
 462
 463         if(sock >= listen_sockets)
 464                 sock = 0;                               /* If none is available, just use the first and hope for the best. */
 465
 466         /* Send the packet */
 467
 468 #if defined(SOL_IP) && defined(IP_TOS)
 469         if(priorityinheritance && origpriority != priority
 470            && listen_socket[sock].sa.sa.sa_family == AF_INET) {
 471                 priority = origpriority;
 472                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting outgoing packet priority to %d", priority);
 473                 if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof priority))     /* SO_PRIORITY doesn't seem to work */
 474                         logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
 475         }
 476 #endif
 477
 478         if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa)) < 0 && !sockwouldblock(sockerrno)) {
 479                 if(sockmsgsize(sockerrno)) {
 480                         if(n->maxmtu >= origlen)
 481                                 n->maxmtu = origlen - 1;
 482                         if(n->mtu >= origlen)
 483                                 n->mtu = origlen - 1;
 484                 } else
 485                         logger(LOG_ERR, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno));
 486         }
 487
 488 end:
 489         origpkt->len = origlen;
 490 }
 491
 492 /*
 493   send a packet to the given vpn ip.
 494 */
 495 void send_packet(const node_t *n, vpn_packet_t *packet) {
 496         node_t *via;
 497
 498         if(n == myself) {
 499                 if(overwrite_mac)
 500                          memcpy(packet->data, mymac.x, ETH_ALEN);
 501                 write_packet(packet);
 502                 return;
 503         }
 504
 505         ifdebug(TRAFFIC) logger(LOG_ERR, "Sending packet of %d bytes to %s (%s)",
 506                            packet->len, n->name, n->hostname);
 507
 508         if(!n->status.reachable) {
 509                 ifdebug(TRAFFIC) logger(LOG_INFO, "Node %s (%s) is not reachable",
 510                                    n->name, n->hostname);
 511                 return;
 512         }
 513
 514         via = (packet->priority == -1 || n->via == myself) ? n->nexthop : n->via;
 515
 516         if(via != n)
 517                 ifdebug(TRAFFIC) logger(LOG_INFO, "Sending packet to %s via %s (%s)",
 518                            n->name, via->name, n->via->hostname);
 519
 520         if(packet->priority == -1 || ((myself->options | via->options) & OPTION_TCPONLY)) {
 521                 if(!send_tcppacket(via->connection, packet))
 522                         terminate_connection(via->connection, true);
 523         } else
 524                 send_udppacket(via, packet);
 525 }
 526
 527 /* Broadcast a packet using the minimum spanning tree */
 528
 529 void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
 530         splay_node_t *node;
 531         connection_t *c;
 532
 533         ifdebug(TRAFFIC) logger(LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)",
 534                            packet->len, from->name, from->hostname);
 535
 536         if(from != myself) {
 537                 send_packet(myself, packet);
 538
 539                 // In TunnelServer mode, do not forward broadcast packets.
 540                 // The MST might not be valid and create loops.
 541                 if(tunnelserver)
 542                         return;
 543         }
 544
 545         for(node = connection_tree->head; node; node = node->next) {
 546                 c = node->data;
 547
 548                 if(c->status.active && c->status.mst && c != from->nexthop->connection)
 549                         send_packet(c->node, packet);
 550         }
 551 }
 552
 553 static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
 554         splay_node_t *node;
 555         node_t *n, *found = NULL;
 556         static time_t last_hard_try = 0;
 557         time_t now = time(NULL);
 558
 559         if(last_hard_try == now)
 560                 return NULL;
 561         else
 562                 last_hard_try = now;
 563
 564         for(node = node_tree->head; node; node = node->next) {
 565                 n = node->data;
 566
 567                 if(n == myself || !n->status.reachable || !digest_active(&n->indigest))
 568                         continue;
 569
 570                 if(try_mac(n, pkt)) {
 571                         found = n;
 572                         break;
 573                 }
 574         }
 575
 576         return found;
 577 }
 578
 579 void handle_incoming_vpn_data(int sock, short events, void *data) {
 580         vpn_packet_t pkt;
 581         char *hostname;
 582         sockaddr_t from;
 583         socklen_t fromlen = sizeof from;
 584         node_t *n;
 585         int len;
 586
 587         len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 588
 589         if(len <= 0 || len > MAXSIZE) {
 590                 if(!sockwouldblock(sockerrno))
 591                         logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
 592                 return;
 593         }
 594
 595         pkt.len = len;
 596
 597         sockaddrunmap(&from);           /* Some braindead IPv6 implementations do stupid things. */
 598
 599         n = lookup_node_udp(&from);
 600
 601         if(!n) {
 602                 n = try_harder(&from, &pkt);
 603                 if(n)
 604                         update_node_udp(n, &from);
 605                 else ifdebug(PROTOCOL) {
 606                         hostname = sockaddr2hostname(&from);
 607                         logger(LOG_WARNING, "Received UDP packet from unknown source %s", hostname);
 608                         free(hostname);
 609                         return;
 610                 }
 611                 else
 612                         return;
 613         }
 614
 615         receive_udppacket(n, &pkt);
 616 }
 617
 618 void handle_device_data(int sock, short events, void *data) {
 619         vpn_packet_t packet;
 620
 621         if(read_packet(&packet))
 622                 route(myself, &packet);
 623 }