tinc-vpn.org Git - tinc/blob - src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
   4                   2000-2002 Guus Sliepen <guus@sliepen.warande.net>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: net_setup.c,v 1.1.2.16 2002/06/02 16:06:33 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <netdb.h>
  28 #include <netinet/in.h>
  29 #ifdef HAVE_LINUX
  30  #include <netinet/ip.h>
  31  #include <netinet/tcp.h>
  32 #endif
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <signal.h>
  37 #include <sys/time.h>
  38 #include <sys/types.h>
  39 #include <syslog.h>
  40 #include <unistd.h>
  41 #include <sys/ioctl.h>
  42 /* SunOS really wants sys/socket.h BEFORE net/if.h,
  43    and FreeBSD wants these lines below the rest. */
  44 #include <arpa/inet.h>
  45 #include <sys/socket.h>
  46 #include <net/if.h>
  47
  48 #include <openssl/pem.h>
  49 #include <openssl/rsa.h>
  50 #include <openssl/rand.h>
  51
  52 #include <utils.h>
  53 #include <xalloc.h>
  54 #include <avl_tree.h>
  55 #include <list.h>
  56
  57 #include "conf.h"
  58 #include "connection.h"
  59 #include "meta.h"
  60 #include "net.h"
  61 #include "netutl.h"
  62 #include "process.h"
  63 #include "protocol.h"
  64 #include "subnet.h"
  65 #include "graph.h"
  66 #include "process.h"
  67 #include "route.h"
  68 #include "device.h"
  69 #include "event.h"
  70
  71 #include "system.h"
  72
  73 char *myport;
  74
  75 int read_rsa_public_key(connection_t *c)
  76 {
  77   FILE *fp;
  78   char *fname;
  79   char *key;
  80 cp
  81   if(!c->rsa_key)
  82     c->rsa_key = RSA_new();
  83
  84   /* First, check for simple PublicKey statement */
  85
  86   if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key))
  87     {
  88       BN_hex2bn(&c->rsa_key->n, key);
  89       BN_hex2bn(&c->rsa_key->e, "FFFF");
  90       free(key);
  91       return 0;
  92     }
  93
  94   /* Else, check for PublicKeyFile statement and read it */
  95
  96   if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
  97     {
  98       if(is_safe_path(fname))
  99         {
 100           if((fp = fopen(fname, "r")) == NULL)
 101             {
 102               syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 103                      fname, strerror(errno));
 104               free(fname);
 105               return -1;
 106             }
 107           free(fname);
 108           c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 109           fclose(fp);
 110           if(c->rsa_key)
 111             return 0; /* Woohoo. */
 112
 113           /* If it fails, try PEM_read_RSA_PUBKEY. */
 114           if((fp = fopen(fname, "r")) == NULL)
 115             {
 116               syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 117                      fname, strerror(errno));
 118               free(fname);
 119               return -1;
 120             }
 121           free(fname);
 122           c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 123           fclose(fp);
 124           if(c->rsa_key)
 125             return 0;
 126
 127           syslog(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 128                  fname, strerror(errno));
 129           return -1;
 130         }
 131       else
 132         {
 133           free(fname);
 134           return -1;
 135         }
 136     }
 137
 138   /* Else, check if a harnessed public key is in the config file */
 139
 140   asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 141   if((fp = fopen(fname, "r")))
 142     {
 143       c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 144       fclose(fp);
 145     }
 146
 147   free(fname);
 148
 149   if(c->rsa_key)
 150     return 0;
 151
 152   /* Try again with PEM_read_RSA_PUBKEY. */
 153
 154   asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 155   if((fp = fopen(fname, "r")))
 156     {
 157       c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 158       fclose(fp);
 159     }
 160
 161   free(fname);
 162
 163   if(c->rsa_key)
 164     return 0;
 165
 166   syslog(LOG_ERR, _("No public key for %s specified!"), c->name);
 167   return -1;
 168 }
 169
 170 int read_rsa_private_key(void)
 171 {
 172   FILE *fp;
 173   char *fname, *key;
 174 cp
 175   if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key))
 176     {
 177       myself->connection->rsa_key = RSA_new();
 178       BN_hex2bn(&myself->connection->rsa_key->d, key);
 179       BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 180       free(key);
 181       return 0;
 182     }
 183
 184   if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 185     asprintf(&fname, "%s/rsa_key.priv", confbase);
 186
 187   if(is_safe_path(fname))
 188     {
 189       if((fp = fopen(fname, "r")) == NULL)
 190         {
 191           syslog(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 192                  fname, strerror(errno));
 193           free(fname);
 194           return -1;
 195         }
 196       free(fname);
 197       myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 198       fclose(fp);
 199       if(!myself->connection->rsa_key)
 200         {
 201           syslog(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 202                  fname, strerror(errno));
 203           return -1;
 204         }
 205       return 0;
 206     }
 207
 208   free(fname);
 209   return -1;
 210 }
 211
 212 /*
 213   Configure node_t myself and set up the local sockets (listen only)
 214 */
 215 int setup_myself(void)
 216 {
 217   config_t *cfg;
 218   subnet_t *subnet;
 219   char *name, *hostname, *mode, *afname, *cipher, *digest;
 220   char *address = NULL;
 221   struct addrinfo hint, *ai, *aip;
 222   int choice, err;
 223 cp
 224   myself = new_node();
 225   myself->connection = new_connection();
 226   init_configuration(&myself->connection->config_tree);
 227
 228   asprintf(&myself->hostname, _("MYSELF"));
 229   asprintf(&myself->connection->hostname, _("MYSELF"));
 230
 231   myself->connection->options = 0;
 232   myself->connection->protocol_version = PROT_CURRENT;
 233
 234   if(!get_config_string(lookup_config(config_tree, "Name"), &name)) /* Not acceptable */
 235     {
 236       syslog(LOG_ERR, _("Name for tinc daemon required!"));
 237       return -1;
 238     }
 239
 240   if(check_id(name))
 241     {
 242       syslog(LOG_ERR, _("Invalid name for myself!"));
 243       free(name);
 244       return -1;
 245     }
 246
 247   myself->name = name;
 248   myself->connection->name = xstrdup(name);
 249
 250 cp
 251   if(read_rsa_private_key())
 252     return -1;
 253
 254   if(read_connection_config(myself->connection))
 255     {
 256       syslog(LOG_ERR, _("Cannot open host configuration file for myself!"));
 257       return -1;
 258     }
 259
 260   if(read_rsa_public_key(myself->connection))
 261     return -1;
 262 cp
 263
 264   if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 265     asprintf(&myport, "655");
 266
 267 /* Read in all the subnets specified in the host configuration file */
 268
 269   cfg = lookup_config(myself->connection->config_tree, "Subnet");
 270
 271   while(cfg)
 272     {
 273       if(!get_config_subnet(cfg, &subnet))
 274         return -1;
 275
 276       subnet_add(myself, subnet);
 277
 278       cfg = lookup_config_next(myself->connection->config_tree, cfg);
 279     }
 280
 281 cp
 282   /* Check some options */
 283
 284   if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
 285     if(choice)
 286       myself->options |= OPTION_INDIRECT;
 287
 288   if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
 289     if(choice)
 290       myself->options |= OPTION_TCPONLY;
 291
 292   if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice))
 293     if(choice)
 294       myself->options |= OPTION_INDIRECT;
 295
 296   if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
 297     if(choice)
 298       myself->options |= OPTION_TCPONLY;
 299
 300   if(myself->options & OPTION_TCPONLY)
 301     myself->options |= OPTION_INDIRECT;
 302
 303   if(get_config_string(lookup_config(config_tree, "Mode"), &mode))
 304     {
 305       if(!strcasecmp(mode, "router"))
 306         routing_mode = RMODE_ROUTER;
 307       else if (!strcasecmp(mode, "switch"))
 308         routing_mode = RMODE_SWITCH;
 309       else if (!strcasecmp(mode, "hub"))
 310         routing_mode = RMODE_HUB;
 311       else
 312         {
 313           syslog(LOG_ERR, _("Invalid routing mode!"));
 314           return -1;
 315         }
 316       free(mode);
 317     }
 318   else
 319     routing_mode = RMODE_ROUTER;
 320
 321   get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 322 #if !defined(SOL_IP) || !defined(IP_TOS)
 323   if(priorityinheritance)
 324     syslog(LOG_WARNING, _("PriorityInheritance not supported on this platform"));
 325 #endif
 326
 327   if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 328     macexpire= 600;
 329
 330   if(get_config_int(lookup_config(myself->connection->config_tree, "MaxTimeout"), &maxtimeout))
 331     {
 332       if(maxtimeout <= 0)
 333         {
 334           syslog(LOG_ERR, _("Bogus maximum timeout!"));
 335           return -1;
 336         }
 337     }
 338   else
 339     maxtimeout = 900;
 340
 341   if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname))
 342     {
 343       if(!strcasecmp(afname, "IPv4"))
 344         addressfamily = AF_INET;
 345       else if (!strcasecmp(afname, "IPv6"))
 346         addressfamily = AF_INET6;
 347       else if (!strcasecmp(afname, "any"))
 348         addressfamily = AF_UNSPEC;
 349       else
 350         {
 351           syslog(LOG_ERR, _("Invalid address family!"));
 352           return -1;
 353         }
 354       free(afname);
 355     }
 356   else
 357     addressfamily = AF_INET;
 358
 359   get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 360 cp
 361   /* Generate packet encryption key */
 362
 363   if(get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher))
 364     {
 365       if(!strcasecmp(cipher, "none"))
 366         {
 367           myself->cipher = NULL;
 368         }
 369       else
 370         {
 371           if(!(myself->cipher = EVP_get_cipherbyname(cipher)))
 372             {
 373               syslog(LOG_ERR, _("Unrecognized cipher type!"));
 374               return -1;
 375             }
 376         }
 377     }
 378   else
 379     myself->cipher = EVP_bf_cbc();
 380
 381   if(myself->cipher)
 382     myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 383   else
 384     myself->keylength = 1;
 385
 386   myself->connection->outcipher = EVP_bf_ofb();
 387
 388   myself->key = (char *)xmalloc(myself->keylength);
 389   RAND_pseudo_bytes(myself->key, myself->keylength);
 390
 391   if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 392     keylifetime = 3600;
 393
 394   keyexpires = now + keylifetime;
 395
 396   /* Check if we want to use message authentication codes... */
 397
 398   if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest))
 399     {
 400       if(!strcasecmp(digest, "none"))
 401         {
 402           myself->digest = NULL;
 403         }
 404       else
 405         {
 406           if(!(myself->digest = EVP_get_digestbyname(digest)))
 407             {
 408               syslog(LOG_ERR, _("Unrecognized digest type!"));
 409               return -1;
 410             }
 411         }
 412     }
 413   else
 414     myself->digest = EVP_sha1();
 415
 416   myself->connection->outdigest = EVP_sha1();
 417
 418   if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->maclength))
 419     {
 420       if(myself->digest)
 421         {
 422           if(myself->maclength > myself->digest->md_size)
 423             {
 424               syslog(LOG_ERR, _("MAC length exceeds size of digest!"));
 425               return -1;
 426             }
 427           else if (myself->maclength < 0)
 428             {
 429               syslog(LOG_ERR, _("Bogus MAC length!"));
 430               return -1;
 431             }
 432         }
 433     }
 434   else
 435     myself->maclength = 4;
 436
 437   myself->connection->outmaclength = 0;
 438
 439   /* Compression */
 440
 441   if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->compression))
 442     {
 443       if(myself->compression < 0 || myself->compression > 9)
 444         {
 445           syslog(LOG_ERR, _("Bogus compression level!"));
 446           return -1;
 447         }
 448     }
 449   else
 450     myself->compression = 0;
 451
 452   myself->connection->outcompression = 0;
 453 cp
 454   /* Done */
 455
 456   myself->nexthop = myself;
 457   myself->via = myself;
 458   myself->status.active = 1;
 459   myself->status.reachable = 1;
 460   node_add(myself);
 461
 462   graph();
 463
 464 cp
 465   /* Open sockets */
 466
 467   memset(&hint, 0, sizeof(hint));
 468
 469   get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 470
 471   hint.ai_family = addressfamily;
 472   hint.ai_socktype = SOCK_STREAM;
 473   hint.ai_protocol = IPPROTO_TCP;
 474   hint.ai_flags = AI_PASSIVE;
 475
 476   if((err = getaddrinfo(address, myport, &hint, &ai)) || !ai)
 477     {
 478       syslog(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(err));
 479       return -1;
 480     }
 481
 482   for(aip = ai; aip; aip = aip->ai_next)
 483     {
 484       if((listen_socket[listen_sockets].tcp = setup_listen_socket((sockaddr_t *)aip->ai_addr)) < 0)
 485         continue;
 486
 487       if((listen_socket[listen_sockets].udp = setup_vpn_in_socket((sockaddr_t *)aip->ai_addr)) < 0)
 488         continue;
 489
 490       if(debug_lvl >= DEBUG_CONNECTIONS)
 491         {
 492           hostname = sockaddr2hostname((sockaddr_t *)aip->ai_addr);
 493           syslog(LOG_NOTICE, _("Listening on %s"), hostname);
 494           free(hostname);
 495         }
 496
 497       listen_socket[listen_sockets].sa.sa = *aip->ai_addr;
 498       listen_sockets++;
 499     }
 500
 501   freeaddrinfo(ai);
 502
 503   if(listen_sockets)
 504     syslog(LOG_NOTICE, _("Ready"));
 505   else
 506     {
 507       syslog(LOG_ERR, _("Unable to create any listening socket!"));
 508       return -1;
 509     }
 510 cp
 511   return 0;
 512 }
 513
 514 /*
 515   setup all initial network connections
 516 */
 517 int setup_network_connections(void)
 518 {
 519 cp
 520   now = time(NULL);
 521
 522   init_connections();
 523   init_subnets();
 524   init_nodes();
 525   init_edges();
 526   init_events();
 527   init_requests();
 528
 529   if(get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 530     {
 531       if(pingtimeout < 1)
 532         {
 533           pingtimeout = 86400;
 534         }
 535     }
 536   else
 537     pingtimeout = 60;
 538
 539   if(setup_device() < 0)
 540     return -1;
 541
 542   /* Run tinc-up script to further initialize the tap interface */
 543   execute_script("tinc-up");
 544
 545   if(setup_myself() < 0)
 546     return -1;
 547
 548   try_outgoing_connections();
 549 cp
 550   return 0;
 551 }
 552
 553 /*
 554   close all open network connections
 555 */
 556 void close_network_connections(void)
 557 {
 558   avl_node_t *node, *next;
 559   connection_t *c;
 560   int i;
 561 cp
 562   for(node = connection_tree->head; node; node = next)
 563     {
 564       next = node->next;
 565       c = (connection_t *)node->data;
 566       if(c->outgoing)
 567         free(c->outgoing->name), free(c->outgoing), c->outgoing = NULL;
 568       terminate_connection(c, 0);
 569     }
 570
 571   if(myself && myself->connection)
 572     terminate_connection(myself->connection, 0);
 573
 574   for(i = 0; i < listen_sockets; i++)
 575     {
 576       close(listen_socket[i].tcp);
 577       close(listen_socket[i].udp);
 578     }
 579
 580   exit_requests();
 581   exit_events();
 582   exit_edges();
 583   exit_subnets();
 584   exit_nodes();
 585   exit_connections();
 586
 587   execute_script("tinc-down");
 588
 589   close_device();
 590 cp
 591   return;
 592 }