git.meshlink.io Git - meshlink/blob - src/net_packet.c

   1 /*
   2     net_packet.c -- Handles in- and outgoing VPN packets
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2011 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                 if(!n->minmtu) {
  91                         n->mtuprobes = 31;
  92                         timeout = pinginterval;
  93                         goto end;
  94                 }
  95
  96                 ifdebug(TRAFFIC) logger(LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname);
  97                 n->mtuprobes = 1;
  98                 n->minmtu = 0;
  99                 n->maxmtu = MTU;
 100         }
 101
 102         if(n->mtuprobes >= 10 && n->mtuprobes < 32 && !n->minmtu) {
 103                 ifdebug(TRAFFIC) logger(LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname);
 104                 n->mtuprobes = 31;
 105         }
 106
 107         if(n->mtuprobes == 30 || (n->mtuprobes < 30 && n->minmtu >= n->maxmtu)) {
 108                 if(n->minmtu > n->maxmtu)
 109                         n->minmtu = n->maxmtu;
 110                 else
 111                         n->maxmtu = n->minmtu;
 112                 n->mtu = n->minmtu;
 113                 ifdebug(TRAFFIC) logger(LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
 114                 n->mtuprobes = 31;
 115         }
 116
 117         if(n->mtuprobes == 31) {
 118                 timeout = pinginterval;
 119                 goto end;
 120         } else if(n->mtuprobes == 32) {
 121                 timeout = pingtimeout;
 122         }
 123
 124         for(i = 0; i < 3; i++) {
 125                 if(n->maxmtu <= n->minmtu)
 126                         len = n->maxmtu;
 127                 else
 128                         len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
 129
 130                 if(len < 64)
 131                         len = 64;
 132
 133                 memset(packet.data, 0, 14);
 134                 randomize(packet.data + 14, len - 14);
 135                 packet.len = len;
 136                 packet.priority = 0;
 137
 138                 ifdebug(TRAFFIC) logger(LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname);
 139
 140                 send_udppacket(n, &packet);
 141         }
 142
 143 end:
 144         event_add(&n->mtuevent, &(struct timeval){timeout, 0});
 145 }
 146
 147 void send_mtu_probe(node_t *n) {
 148         if(!timeout_initialized(&n->mtuevent))
 149                 timeout_set(&n->mtuevent, send_mtu_probe_handler, n);
 150         send_mtu_probe_handler(0, 0, n);
 151 }
 152
 153 void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 154         ifdebug(TRAFFIC) logger(LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname);
 155
 156         if(!packet->data[0]) {
 157                 packet->data[0] = 1;
 158                 send_udppacket(n, packet);
 159         } else {
 160                 if(n->mtuprobes > 30) {
 161                         if(n->minmtu)
 162                                 n->mtuprobes = 30;
 163                         else
 164                                 n->mtuprobes = 1;
 165                 }
 166
 167                 if(len > n->maxmtu)
 168                         len = n->maxmtu;
 169                 if(n->minmtu < len)
 170                         n->minmtu = len;
 171         }
 172 }
 173
 174 static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 175         if(level == 0) {
 176                 memcpy(dest, source, len);
 177                 return len;
 178         } else if(level == 10) {
 179 #ifdef HAVE_LZO
 180                 lzo_uint lzolen = MAXSIZE;
 181                 lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
 182                 return lzolen;
 183 #else
 184                 return -1;
 185 #endif
 186         } else if(level < 10) {
 187 #ifdef HAVE_ZLIB
 188                 unsigned long destlen = MAXSIZE;
 189                 if(compress2(dest, &destlen, source, len, level) == Z_OK)
 190                         return destlen;
 191                 else
 192 #endif
 193                         return -1;
 194         } else {
 195 #ifdef HAVE_LZO
 196                 lzo_uint lzolen = MAXSIZE;
 197                 lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
 198                 return lzolen;
 199 #else
 200                 return -1;
 201 #endif
 202         }
 203
 204         return -1;
 205 }
 206
 207 static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 208         if(level == 0) {
 209                 memcpy(dest, source, len);
 210                 return len;
 211         } else if(level > 9) {
 212 #ifdef HAVE_LZO
 213                 lzo_uint lzolen = MAXSIZE;
 214                 if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
 215                         return lzolen;
 216                 else
 217 #endif
 218                         return -1;
 219         }
 220 #ifdef HAVE_ZLIB
 221         else {
 222                 unsigned long destlen = MAXSIZE;
 223                 if(uncompress(dest, &destlen, source, len) == Z_OK)
 224                         return destlen;
 225                 else
 226                         return -1;
 227         }
 228 #endif
 229
 230         return -1;
 231 }
 232
 233 /* VPN packet I/O */
 234
 235 static void receive_packet(node_t *n, vpn_packet_t *packet) {
 236         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Received packet of %d bytes from %s (%s)",
 237                            packet->len, n->name, n->hostname);
 238
 239         route(n, packet);
 240 }
 241
 242 static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
 243         if(!digest_active(&n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest))
 244                 return false;
 245
 246         return digest_verify(&n->indigest, &inpkt->seqno, inpkt->len - n->indigest.maclength, (const char *)&inpkt->seqno + inpkt->len - n->indigest.maclength);
 247 }
 248
 249 static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 250         vpn_packet_t pkt1, pkt2;
 251         vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 252         int nextpkt = 0;
 253         vpn_packet_t *outpkt = pkt[0];
 254         size_t outlen;
 255         int i;
 256
 257         if(!cipher_active(&n->incipher)) {
 258                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
 259                                         n->name, n->hostname);
 260                 return;
 261         }
 262
 263         /* Check packet length */
 264
 265         if(inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest)) {
 266                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)",
 267                                         n->name, n->hostname);
 268                 return;
 269         }
 270
 271         /* Check the message authentication code */
 272
 273         if(digest_active(&n->indigest)) {
 274                 inpkt->len -= n->indigest.maclength;
 275                 if(!digest_verify(&n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) {
 276                         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname);
 277                         return;
 278                 }
 279         }
 280         /* Decrypt the packet */
 281
 282         if(cipher_active(&n->incipher)) {
 283                 outpkt = pkt[nextpkt++];
 284                 outlen = MAXSIZE;
 285
 286                 if(!cipher_decrypt(&n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
 287                         ifdebug(TRAFFIC) logger(LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname);
 288                         return;
 289                 }
 290
 291                 outpkt->len = outlen;
 292                 inpkt = outpkt;
 293         }
 294
 295         /* Check the sequence number */
 296
 297         inpkt->len -= sizeof inpkt->seqno;
 298         inpkt->seqno = ntohl(inpkt->seqno);
 299
 300         if(replaywin) {
 301                 if(inpkt->seqno != n->received_seqno + 1) {
 302                         if(inpkt->seqno >= n->received_seqno + replaywin * 8) {
 303                                 if(n->farfuture++ < replaywin >> 2) {
 304                                         logger(LOG_WARNING, "Packet from %s (%s) is %d seqs in the future, dropped (%u)",
 305                                                 n->name, n->hostname, inpkt->seqno - n->received_seqno - 1, n->farfuture);
 306                                         return;
 307                                 }
 308                                 logger(LOG_WARNING, "Lost %d packets from %s (%s)",
 309                                                 inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
 310                                 memset(n->late, 0, replaywin);
 311                         } else if (inpkt->seqno <= n->received_seqno) {
 312                                 if((n->received_seqno >= replaywin * 8 && inpkt->seqno <= n->received_seqno - replaywin * 8) || !(n->late[(inpkt->seqno / 8) % replaywin] & (1 << inpkt->seqno % 8))) {
 313                                         logger(LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d",
 314                                                 n->name, n->hostname, inpkt->seqno, n->received_seqno);
 315                                         return;
 316                                 }
 317                         } else {
 318                                 for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
 319                                         n->late[(i / 8) % replaywin] |= 1 << i % 8;
 320                         }
 321                 }
 322
 323                 n->farfuture = 0;
 324                 n->late[(inpkt->seqno / 8) % replaywin] &= ~(1 << inpkt->seqno % 8);
 325         }
 326
 327         if(inpkt->seqno > n->received_seqno)
 328                 n->received_seqno = inpkt->seqno;
 329
 330         if(n->received_seqno > MAX_SEQNO)
 331                 regenerate_key();
 332
 333         /* Decompress the packet */
 334
 335         length_t origlen = inpkt->len;
 336
 337         if(n->incompression) {
 338                 outpkt = pkt[nextpkt++];
 339
 340                 if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression)) < 0) {
 341                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while uncompressing packet from %s (%s)",
 342                                                  n->name, n->hostname);
 343                         return;
 344                 }
 345
 346                 inpkt = outpkt;
 347
 348                 origlen -= MTU/64 + 20;
 349         }
 350
 351         inpkt->priority = 0;
 352
 353         if(!inpkt->data[12] && !inpkt->data[13])
 354                 mtu_probe_h(n, inpkt, origlen);
 355         else
 356                 receive_packet(n, inpkt);
 357 }
 358
 359 void receive_tcppacket(connection_t *c, char *buffer, int len) {
 360         vpn_packet_t outpkt;
 361
 362         outpkt.len = len;
 363         if(c->options & OPTION_TCPONLY)
 364                 outpkt.priority = 0;
 365         else
 366                 outpkt.priority = -1;
 367         memcpy(outpkt.data, buffer, len);
 368
 369         receive_packet(c->node, &outpkt);
 370 }
 371
 372 static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 373         vpn_packet_t pkt1, pkt2;
 374         vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 375         vpn_packet_t *inpkt = origpkt;
 376         int nextpkt = 0;
 377         vpn_packet_t *outpkt;
 378         int origlen;
 379         size_t outlen;
 380 #if defined(SOL_IP) && defined(IP_TOS)
 381         static int priority = 0;
 382 #endif
 383         int origpriority;
 384         int sock;
 385
 386         if(!n->status.reachable) {
 387                 ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname);
 388                 return;
 389         }
 390
 391         /* Make sure we have a valid key */
 392
 393         if(!n->status.validkey) {
 394                 time_t now = time(NULL);
 395
 396                 ifdebug(TRAFFIC) logger(LOG_INFO,
 397                                    "No valid key known yet for %s (%s), forwarding via TCP",
 398                                    n->name, n->hostname);
 399
 400                 if(n->last_req_key + 10 < now) {
 401                         send_req_key(n);
 402                         n->last_req_key = now;
 403                 }
 404
 405                 send_tcppacket(n->nexthop->connection, origpkt);
 406
 407                 return;
 408         }
 409
 410         if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
 411                 ifdebug(TRAFFIC) logger(LOG_INFO,
 412                                 "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
 413                                 n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
 414
 415                 if(n != n->nexthop)
 416                         send_packet(n->nexthop, origpkt);
 417                 else
 418                         send_tcppacket(n->nexthop->connection, origpkt);
 419
 420                 return;
 421         }
 422
 423         origlen = inpkt->len;
 424         origpriority = inpkt->priority;
 425
 426         /* Compress the packet */
 427
 428         if(n->outcompression) {
 429                 outpkt = pkt[nextpkt++];
 430
 431                 if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression)) < 0) {
 432                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while compressing packet to %s (%s)",
 433                                    n->name, n->hostname);
 434                         return;
 435                 }
 436
 437                 inpkt = outpkt;
 438         }
 439
 440         /* Add sequence number */
 441
 442         inpkt->seqno = htonl(++(n->sent_seqno));
 443         inpkt->len += sizeof inpkt->seqno;
 444
 445         /* Encrypt the packet */
 446
 447         if(cipher_active(&n->outcipher)) {
 448                 outpkt = pkt[nextpkt++];
 449                 outlen = MAXSIZE;
 450
 451                 if(!cipher_encrypt(&n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
 452                         ifdebug(TRAFFIC) logger(LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname);
 453                         goto end;
 454                 }
 455
 456                 outpkt->len = outlen;
 457                 inpkt = outpkt;
 458         }
 459
 460         /* Add the message authentication code */
 461
 462         if(digest_active(&n->outdigest)) {
 463                 digest_create(&n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len);
 464                 inpkt->len += digest_length(&n->outdigest);
 465         }
 466
 467         /* Determine which socket we have to use */
 468
 469         for(sock = 0; sock < listen_sockets; sock++)
 470                 if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family)
 471                         break;
 472
 473         if(sock >= listen_sockets)
 474                 sock = 0;                               /* If none is available, just use the first and hope for the best. */
 475
 476         /* Send the packet */
 477
 478 #if defined(SOL_IP) && defined(IP_TOS)
 479         if(priorityinheritance && origpriority != priority
 480            && listen_socket[sock].sa.sa.sa_family == AF_INET) {
 481                 priority = origpriority;
 482                 ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting outgoing packet priority to %d", priority);
 483                 if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof priority))     /* SO_PRIORITY doesn't seem to work */
 484                         logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
 485         }
 486 #endif
 487
 488         if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa)) < 0 && !sockwouldblock(sockerrno)) {
 489                 if(sockmsgsize(sockerrno)) {
 490                         if(n->maxmtu >= origlen)
 491                                 n->maxmtu = origlen - 1;
 492                         if(n->mtu >= origlen)
 493                                 n->mtu = origlen - 1;
 494                 } else
 495                         logger(LOG_ERR, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno));
 496         }
 497
 498 end:
 499         origpkt->len = origlen;
 500 }
 501
 502 /*
 503   send a packet to the given vpn ip.
 504 */
 505 void send_packet(const node_t *n, vpn_packet_t *packet) {
 506         node_t *via;
 507
 508         if(n == myself) {
 509                 if(overwrite_mac)
 510                          memcpy(packet->data, mymac.x, ETH_ALEN);
 511                 write_packet(packet);
 512                 return;
 513         }
 514
 515         ifdebug(TRAFFIC) logger(LOG_ERR, "Sending packet of %d bytes to %s (%s)",
 516                            packet->len, n->name, n->hostname);
 517
 518         if(!n->status.reachable) {
 519                 ifdebug(TRAFFIC) logger(LOG_INFO, "Node %s (%s) is not reachable",
 520                                    n->name, n->hostname);
 521                 return;
 522         }
 523
 524         via = (packet->priority == -1 || n->via == myself) ? n->nexthop : n->via;
 525
 526         if(via != n)
 527                 ifdebug(TRAFFIC) logger(LOG_INFO, "Sending packet to %s via %s (%s)",
 528                            n->name, via->name, n->via->hostname);
 529
 530         if(packet->priority == -1 || ((myself->options | via->options) & OPTION_TCPONLY)) {
 531                 if(!send_tcppacket(via->connection, packet))
 532                         terminate_connection(via->connection, true);
 533         } else
 534                 send_udppacket(via, packet);
 535 }
 536
 537 /* Broadcast a packet using the minimum spanning tree */
 538
 539 void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
 540         splay_node_t *node;
 541         connection_t *c;
 542
 543         ifdebug(TRAFFIC) logger(LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)",
 544                            packet->len, from->name, from->hostname);
 545
 546         if(from != myself) {
 547                 send_packet(myself, packet);
 548
 549                 // In TunnelServer mode, do not forward broadcast packets.
 550                 // The MST might not be valid and create loops.
 551                 if(tunnelserver)
 552                         return;
 553         }
 554
 555         for(node = connection_tree->head; node; node = node->next) {
 556                 c = node->data;
 557
 558                 if(c->status.active && c->status.mst && c != from->nexthop->connection)
 559                         send_packet(c->node, packet);
 560         }
 561 }
 562
 563 static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
 564         splay_node_t *node;
 565         edge_t *e;
 566         node_t *n = NULL;
 567         bool hard = false;
 568         static time_t last_hard_try = 0;
 569         time_t now = time(NULL);
 570
 571         if(last_hard_try == now)
 572                 return NULL;
 573         else
 574                 last_hard_try = now;
 575
 576         for(node = edge_weight_tree->head; node; node = node->next) {
 577                 e = node->data;
 578
 579                 if(e->to == myself)
 580                         continue;
 581
 582                 if(sockaddrcmp_noport(from, &e->address)) {
 583                         if(last_hard_try == now)
 584                                 continue;
 585                         hard = true;
 586                 }
 587
 588                 if(!try_mac(e->to, pkt))
 589                         continue;
 590
 591                 n = e->to;
 592                 break;
 593         }
 594
 595         if(hard)
 596                 last_hard_try = now;
 597
 598         return n;
 599 }
 600
 601 void handle_incoming_vpn_data(int sock, short events, void *data) {
 602         vpn_packet_t pkt;
 603         char *hostname;
 604         sockaddr_t from;
 605         socklen_t fromlen = sizeof from;
 606         node_t *n;
 607         int len;
 608
 609         len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 610
 611         if(len <= 0 || len > MAXSIZE) {
 612                 if(!sockwouldblock(sockerrno))
 613                         logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
 614                 return;
 615         }
 616
 617         pkt.len = len;
 618
 619         sockaddrunmap(&from);           /* Some braindead IPv6 implementations do stupid things. */
 620
 621         n = lookup_node_udp(&from);
 622
 623         if(!n) {
 624                 n = try_harder(&from, &pkt);
 625                 if(n)
 626                         update_node_udp(n, &from);
 627                 else ifdebug(PROTOCOL) {
 628                         hostname = sockaddr2hostname(&from);
 629                         logger(LOG_WARNING, "Received UDP packet from unknown source %s", hostname);
 630                         free(hostname);
 631                         return;
 632                 }
 633                 else
 634                         return;
 635         }
 636
 637         receive_udppacket(n, &pkt);
 638 }
 639
 640 void handle_device_data(int sock, short events, void *data) {
 641         vpn_packet_t packet;
 642
 643         if(read_packet(&packet))
 644                 route(myself, &packet);
 645 }