src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2003 Ivo Timmermans <ivo@o2w.nl>,
   4                   2000-2003 Guus Sliepen <guus@sliepen.eu.org>
   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 1.1.2.35 2003/07/17 15:06:26 guus Exp $
  21 */
  22
  23 #include "system.h"
  24
  25 #include <openssl/pem.h>
  26 #include <openssl/rsa.h>
  27 #include <openssl/rand.h>
  28
  29 #include "avl_tree.h"
  30 #include "conf.h"
  31 #include "connection.h"
  32 #include "device.h"
  33 #include "event.h"
  34 #include "graph.h"
  35 #include "logger.h"
  36 #include "net.h"
  37 #include "netutl.h"
  38 #include "process.h"
  39 #include "protocol.h"
  40 #include "route.h"
  41 #include "subnet.h"
  42 #include "utils.h"
  43 #include "xalloc.h"
  44
  45 char *myport;
  46
  47 int read_rsa_public_key(connection_t *c)
  48 {
  49         FILE *fp;
  50         char *fname;
  51         char *key;
  52
  53         cp();
  54
  55         if(!c->rsa_key) {
  56                 c->rsa_key = RSA_new();
  57 //              RSA_blinding_on(c->rsa_key, NULL);
  58         }
  59
  60         /* First, check for simple PublicKey statement */
  61
  62         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  63                 BN_hex2bn(&c->rsa_key->n, key);
  64                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  65                 free(key);
  66                 return 0;
  67         }
  68
  69         /* Else, check for PublicKeyFile statement and read it */
  70
  71         if(get_config_string
  72            (lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  73                 if(is_safe_path(fname)) {
  74                         fp = fopen(fname, "r");
  75
  76                         if(!fp) {
  77                                 logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  78                                            fname, strerror(errno));
  79                                 free(fname);
  80                                 return -1;
  81                         }
  82
  83                         free(fname);
  84                         c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  85                         fclose(fp);
  86
  87                         if(c->rsa_key)
  88                                 return 0;               /* Woohoo. */
  89
  90                         /* If it fails, try PEM_read_RSA_PUBKEY. */
  91                         fp = fopen(fname, "r");
  92
  93                         if(!fp) {
  94                                 logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  95                                            fname, strerror(errno));
  96                                 free(fname);
  97                                 return -1;
  98                         }
  99
 100                         free(fname);
 101                         c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 102                         fclose(fp);
 103
 104                         if(c->rsa_key) {
 105 //                              RSA_blinding_on(c->rsa_key, NULL);
 106                                 return 0;
 107                         }
 108
 109                         logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 110                                    fname, strerror(errno));
 111                         return -1;
 112                 } else {
 113                         free(fname);
 114                         return -1;
 115                 }
 116         }
 117
 118         /* Else, check if a harnessed public key is in the config file */
 119
 120         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 121         fp = fopen(fname, "r");
 122
 123         if(fp) {
 124                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 125                 fclose(fp);
 126         }
 127
 128         free(fname);
 129
 130         if(c->rsa_key)
 131                 return 0;
 132
 133         /* Try again with PEM_read_RSA_PUBKEY. */
 134
 135         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 136         fp = fopen(fname, "r");
 137
 138         if(fp) {
 139                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 140 //              RSA_blinding_on(c->rsa_key, NULL);
 141                 fclose(fp);
 142         }
 143
 144         free(fname);
 145
 146         if(c->rsa_key)
 147                 return 0;
 148
 149         logger(LOG_ERR, _("No public key for %s specified!"), c->name);
 150
 151         return -1;
 152 }
 153
 154 int read_rsa_private_key(void)
 155 {
 156         FILE *fp;
 157         char *fname, *key;
 158
 159         cp();
 160
 161         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 162                 myself->connection->rsa_key = RSA_new();
 163 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 164                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 165                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 166                 free(key);
 167                 return 0;
 168         }
 169
 170         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 171                 asprintf(&fname, "%s/rsa_key.priv", confbase);
 172
 173         if(is_safe_path(fname)) {
 174                 fp = fopen(fname, "r");
 175
 176                 if(!fp) {
 177                         logger(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 178                                    fname, strerror(errno));
 179                         free(fname);
 180                         return -1;
 181                 }
 182
 183                 free(fname);
 184                 myself->connection->rsa_key =
 185                         PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 186                 fclose(fp);
 187
 188                 if(!myself->connection->rsa_key) {
 189                         logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 190                                    fname, strerror(errno));
 191                         return -1;
 192                 }
 193
 194                 return 0;
 195         }
 196
 197         free(fname);
 198         return -1;
 199 }
 200
 201 /*
 202   Configure node_t myself and set up the local sockets (listen only)
 203 */
 204 int setup_myself(void)
 205 {
 206         config_t *cfg;
 207         subnet_t *subnet;
 208         char *name, *hostname, *mode, *afname, *cipher, *digest;
 209         char *address = NULL;
 210         struct addrinfo hint, *ai, *aip;
 211         int choice, err;
 212
 213         cp();
 214
 215         myself = new_node();
 216         myself->connection = new_connection();
 217         init_configuration(&myself->connection->config_tree);
 218
 219         asprintf(&myself->hostname, _("MYSELF"));
 220         asprintf(&myself->connection->hostname, _("MYSELF"));
 221
 222         myself->connection->options = 0;
 223         myself->connection->protocol_version = PROT_CURRENT;
 224
 225         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 226                 logger(LOG_ERR, _("Name for tinc daemon required!"));
 227                 return -1;
 228         }
 229
 230         if(check_id(name)) {
 231                 logger(LOG_ERR, _("Invalid name for myself!"));
 232                 free(name);
 233                 return -1;
 234         }
 235
 236         myself->name = name;
 237         myself->connection->name = xstrdup(name);
 238
 239         if(read_rsa_private_key())
 240                 return -1;
 241
 242         if(read_connection_config(myself->connection)) {
 243                 logger(LOG_ERR, _("Cannot open host configuration file for myself!"));
 244                 return -1;
 245         }
 246
 247         if(read_rsa_public_key(myself->connection))
 248                 return -1;
 249
 250         if(!get_config_string
 251            (lookup_config(myself->connection->config_tree, "Port"), &myport))
 252                 asprintf(&myport, "655");
 253
 254         /* Read in all the subnets specified in the host configuration file */
 255
 256         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 257
 258         while(cfg) {
 259                 if(!get_config_subnet(cfg, &subnet))
 260                         return -1;
 261
 262                 subnet_add(myself, subnet);
 263
 264                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 265         }
 266
 267         /* Check some options */
 268
 269         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
 270                 if(choice)
 271                         myself->options |= OPTION_INDIRECT;
 272
 273         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
 274                 if(choice)
 275                         myself->options |= OPTION_TCPONLY;
 276
 277         if(get_config_bool
 278            (lookup_config(myself->connection->config_tree, "IndirectData"),
 279                 &choice))
 280                 if(choice)
 281                         myself->options |= OPTION_INDIRECT;
 282
 283         if(get_config_bool
 284            (lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
 285                 if(choice)
 286                         myself->options |= OPTION_TCPONLY;
 287
 288         if(myself->options & OPTION_TCPONLY)
 289                 myself->options |= OPTION_INDIRECT;
 290
 291         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 292                 if(!strcasecmp(mode, "router"))
 293                         routing_mode = RMODE_ROUTER;
 294                 else if(!strcasecmp(mode, "switch"))
 295                         routing_mode = RMODE_SWITCH;
 296                 else if(!strcasecmp(mode, "hub"))
 297                         routing_mode = RMODE_HUB;
 298                 else {
 299                         logger(LOG_ERR, _("Invalid routing mode!"));
 300                         return -1;
 301                 }
 302                 free(mode);
 303         } else
 304                 routing_mode = RMODE_ROUTER;
 305
 306         get_config_bool(lookup_config(config_tree, "PriorityInheritance"),
 307                                         &priorityinheritance);
 308 #if !defined(SOL_IP) || !defined(IP_TOS)
 309         if(priorityinheritance)
 310                 logger(LOG_WARNING, _("PriorityInheritance not supported on this platform"));
 311 #endif
 312
 313         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 314                 macexpire = 600;
 315
 316         if(get_config_int
 317            (lookup_config(myself->connection->config_tree, "MaxTimeout"),
 318                 &maxtimeout)) {
 319                 if(maxtimeout <= 0) {
 320                         logger(LOG_ERR, _("Bogus maximum timeout!"));
 321                         return -1;
 322                 }
 323         } else
 324                 maxtimeout = 900;
 325
 326         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 327                 if(!strcasecmp(afname, "IPv4"))
 328                         addressfamily = AF_INET;
 329                 else if(!strcasecmp(afname, "IPv6"))
 330                         addressfamily = AF_INET6;
 331                 else if(!strcasecmp(afname, "any"))
 332                         addressfamily = AF_UNSPEC;
 333                 else {
 334                         logger(LOG_ERR, _("Invalid address family!"));
 335                         return -1;
 336                 }
 337                 free(afname);
 338         }
 339
 340         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 341
 342         /* Generate packet encryption key */
 343
 344         if(get_config_string
 345            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 346                 if(!strcasecmp(cipher, "none")) {
 347                         myself->cipher = NULL;
 348                 } else {
 349                         myself->cipher = EVP_get_cipherbyname(cipher);
 350
 351                         if(!myself->cipher) {
 352                                 logger(LOG_ERR, _("Unrecognized cipher type!"));
 353                                 return -1;
 354                         }
 355                 }
 356         } else
 357                 myself->cipher = EVP_bf_cbc();
 358
 359         if(myself->cipher)
 360                 myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 361         else
 362                 myself->keylength = 1;
 363
 364         myself->connection->outcipher = EVP_bf_ofb();
 365
 366         myself->key = (char *) xmalloc(myself->keylength);
 367         RAND_pseudo_bytes(myself->key, myself->keylength);
 368
 369         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 370                 keylifetime = 3600;
 371
 372         keyexpires = now + keylifetime;
 373
 374         EVP_CIPHER_CTX_init(&packet_ctx);
 375         EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, myself->key, myself->key + myself->cipher->key_len);
 376
 377         /* Check if we want to use message authentication codes... */
 378
 379         if(get_config_string
 380            (lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 381                 if(!strcasecmp(digest, "none")) {
 382                         myself->digest = NULL;
 383                 } else {
 384                         myself->digest = EVP_get_digestbyname(digest);
 385
 386                         if(!myself->digest) {
 387                                 logger(LOG_ERR, _("Unrecognized digest type!"));
 388                                 return -1;
 389                         }
 390                 }
 391         } else
 392                 myself->digest = EVP_sha1();
 393
 394         myself->connection->outdigest = EVP_sha1();
 395
 396         if(get_config_int
 397            (lookup_config(myself->connection->config_tree, "MACLength"),
 398                 &myself->maclength)) {
 399                 if(myself->digest) {
 400                         if(myself->maclength > myself->digest->md_size) {
 401                                 logger(LOG_ERR, _("MAC length exceeds size of digest!"));
 402                                 return -1;
 403                         } else if(myself->maclength < 0) {
 404                                 logger(LOG_ERR, _("Bogus MAC length!"));
 405                                 return -1;
 406                         }
 407                 }
 408         } else
 409                 myself->maclength = 4;
 410
 411         myself->connection->outmaclength = 0;
 412
 413         /* Compression */
 414
 415         if(get_config_int
 416            (lookup_config(myself->connection->config_tree, "Compression"),
 417                 &myself->compression)) {
 418                 if(myself->compression < 0 || myself->compression > 11) {
 419                         logger(LOG_ERR, _("Bogus compression level!"));
 420                         return -1;
 421                 }
 422         } else
 423                 myself->compression = 0;
 424
 425         myself->connection->outcompression = 0;
 426
 427         /* Done */
 428
 429         myself->nexthop = myself;
 430         myself->via = myself;
 431         myself->status.active = 1;
 432         myself->status.reachable = 1;
 433         node_add(myself);
 434
 435         graph();
 436
 437         /* Open sockets */
 438
 439         memset(&hint, 0, sizeof(hint));
 440
 441         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 442
 443         hint.ai_family = addressfamily;
 444         hint.ai_socktype = SOCK_STREAM;
 445         hint.ai_protocol = IPPROTO_TCP;
 446         hint.ai_flags = AI_PASSIVE;
 447
 448         err = getaddrinfo(address, myport, &hint, &ai);
 449
 450         if(err || !ai) {
 451                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
 452                            gai_strerror(err));
 453                 return -1;
 454         }
 455
 456         listen_sockets = 0;
 457
 458         for(aip = ai; aip; aip = aip->ai_next) {
 459                 listen_socket[listen_sockets].tcp =
 460                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 461
 462                 if(listen_socket[listen_sockets].tcp < 0)
 463                         continue;
 464
 465                 listen_socket[listen_sockets].udp =
 466                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 467
 468                 if(listen_socket[listen_sockets].udp < 0)
 469                         continue;
 470
 471                 ifdebug(CONNECTIONS) {
 472                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 473                         logger(LOG_NOTICE, _("Listening on %s"), hostname);
 474                         free(hostname);
 475                 }
 476
 477                 listen_socket[listen_sockets].sa.sa = *aip->ai_addr;
 478                 listen_sockets++;
 479         }
 480
 481         freeaddrinfo(ai);
 482
 483         if(listen_sockets)
 484                 logger(LOG_NOTICE, _("Ready"));
 485         else {
 486                 logger(LOG_ERR, _("Unable to create any listening socket!"));
 487                 return -1;
 488         }
 489
 490         return 0;
 491 }
 492
 493 /*
 494   setup all initial network connections
 495 */
 496 int setup_network_connections(void)
 497 {
 498         char *envp[5];
 499         int i;
 500
 501         cp();
 502
 503         now = time(NULL);
 504
 505         init_connections();
 506         init_subnets();
 507         init_nodes();
 508         init_edges();
 509         init_events();
 510         init_requests();
 511
 512         if(get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout)) {
 513                 if(pingtimeout < 1) {
 514                         pingtimeout = 86400;
 515                 }
 516         } else
 517                 pingtimeout = 60;
 518
 519         if(setup_device() < 0)
 520                 return -1;
 521
 522         if(setup_myself() < 0)
 523                 return -1;
 524
 525         /* Run tinc-up script to further initialize the tap interface */
 526         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 527         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 528         asprintf(&envp[2], "INTERFACE=%s", interface ? : "");
 529         asprintf(&envp[3], "NAME=%s", myself->name);
 530         envp[4] = NULL;
 531
 532         execute_script("tinc-up", envp);
 533
 534         for(i = 0; i < 5; i++)
 535                 free(envp[i]);
 536
 537         try_outgoing_connections();
 538
 539         return 0;
 540 }
 541
 542 /*
 543   close all open network connections
 544 */
 545 void close_network_connections(void)
 546 {
 547         avl_node_t *node, *next;
 548         connection_t *c;
 549         char *envp[5];
 550         int i;
 551
 552         cp();
 553
 554         for(node = connection_tree->head; node; node = next) {
 555                 next = node->next;
 556                 c = (connection_t *) node->data;
 557
 558                 if(c->outgoing)
 559                         free(c->outgoing->name), free(c->outgoing), c->outgoing = NULL;
 560                 terminate_connection(c, 0);
 561         }
 562
 563         if(myself && myself->connection)
 564                 terminate_connection(myself->connection, 0);
 565
 566         for(i = 0; i < listen_sockets; i++) {
 567                 close(listen_socket[i].tcp);
 568                 close(listen_socket[i].udp);
 569         }
 570
 571         exit_requests();
 572         exit_events();
 573         exit_edges();
 574         exit_subnets();
 575         exit_nodes();
 576         exit_connections();
 577
 578         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 579         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 580         asprintf(&envp[2], "INTERFACE=%s", interface ? : "");
 581         asprintf(&envp[3], "NAME=%s", myself->name);
 582         envp[4] = NULL;
 583
 584         execute_script("tinc-down", envp);
 585
 586         for(i = 0; i < 4; i++)
 587                 free(envp[i]);
 588
 589         close_device();
 590
 591         return;
 592 }