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

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2006 Guus Sliepen <guus@tinc-vpn.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     $Id$
  21 */
  22
  23 #include "system.h"
  24
  25 #include <openssl/pem.h>
  26 #include <openssl/rsa.h>
  27 #include <openssl/rand.h>
  28 #include <openssl/err.h>
  29 #include <openssl/evp.h>
  30
  31 #include "avl_tree.h"
  32 #include "conf.h"
  33 #include "connection.h"
  34 #include "device.h"
  35 #include "tevent.h"
  36 #include "graph.h"
  37 #include "logger.h"
  38 #include "net.h"
  39 #include "netutl.h"
  40 #include "process.h"
  41 #include "protocol.h"
  42 #include "route.h"
  43 #include "subnet.h"
  44 #include "utils.h"
  45 #include "xalloc.h"
  46
  47 char *myport;
  48 static struct event device_ev;
  49
  50 bool read_rsa_public_key(connection_t *c)
  51 {
  52         FILE *fp;
  53         char *fname;
  54         char *key;
  55
  56         cp();
  57
  58         if(!c->rsa_key) {
  59                 c->rsa_key = RSA_new();
  60 //              RSA_blinding_on(c->rsa_key, NULL);
  61         }
  62
  63         /* First, check for simple PublicKey statement */
  64
  65         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  66                 BN_hex2bn(&c->rsa_key->n, key);
  67                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  68                 free(key);
  69                 return true;
  70         }
  71
  72         /* Else, check for PublicKeyFile statement and read it */
  73
  74         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  75                 fp = fopen(fname, "r");
  76
  77                 if(!fp) {
  78                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  79                                    fname, strerror(errno));
  80                         free(fname);
  81                         return false;
  82                 }
  83
  84                 free(fname);
  85                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  86                 fclose(fp);
  87
  88                 if(c->rsa_key)
  89                         return true;            /* Woohoo. */
  90
  91                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  92                 fp = fopen(fname, "r");
  93
  94                 if(!fp) {
  95                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  96                                    fname, strerror(errno));
  97                         free(fname);
  98                         return false;
  99                 }
 100
 101                 free(fname);
 102                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 103                 fclose(fp);
 104
 105                 if(c->rsa_key) {
 106 //                              RSA_blinding_on(c->rsa_key, NULL);
 107                         return true;
 108                 }
 109
 110                 logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 111                            fname, strerror(errno));
 112                 return false;
 113         }
 114
 115         /* Else, check if a harnessed public key is in the config file */
 116
 117         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 118         fp = fopen(fname, "r");
 119
 120         if(fp) {
 121                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 122                 fclose(fp);
 123         }
 124
 125         free(fname);
 126
 127         if(c->rsa_key)
 128                 return true;
 129
 130         /* Try again with PEM_read_RSA_PUBKEY. */
 131
 132         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 133         fp = fopen(fname, "r");
 134
 135         if(fp) {
 136                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 137 //              RSA_blinding_on(c->rsa_key, NULL);
 138                 fclose(fp);
 139         }
 140
 141         free(fname);
 142
 143         if(c->rsa_key)
 144                 return true;
 145
 146         logger(LOG_ERR, _("No public key for %s specified!"), c->name);
 147
 148         return false;
 149 }
 150
 151 bool read_rsa_private_key(void)
 152 {
 153         FILE *fp;
 154         char *fname, *key, *pubkey;
 155         struct stat s;
 156
 157         cp();
 158
 159         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 160                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
 161                         logger(LOG_ERR, _("PrivateKey used but no PublicKey found!"));
 162                         return false;
 163                 }
 164                 myself->connection->rsa_key = RSA_new();
 165 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 166                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 167                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 168                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 169                 free(key);
 170                 free(pubkey);
 171                 return true;
 172         }
 173
 174         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 175                 asprintf(&fname, "%s/rsa_key.priv", confbase);
 176
 177         fp = fopen(fname, "r");
 178
 179         if(!fp) {
 180                 logger(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 181                            fname, strerror(errno));
 182                 free(fname);
 183                 return false;
 184         }
 185
 186 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 187         if(fstat(fileno(fp), &s)) {
 188                 logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"),
 189                                 fname, strerror(errno));
 190                 free(fname);
 191                 return false;
 192         }
 193
 194         if(s.st_mode & ~0100700)
 195                 logger(LOG_WARNING, _("Warning: insecure file permissions for RSA private key file `%s'!"), fname);
 196 #endif
 197
 198         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 199         fclose(fp);
 200
 201         if(!myself->connection->rsa_key) {
 202                 logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 203                            fname, strerror(errno));
 204                 free(fname);
 205                 return false;
 206         }
 207
 208         free(fname);
 209         return true;
 210 }
 211
 212 /*
 213   Configure node_t myself and set up the local sockets (listen only)
 214 */
 215 bool 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         char *envp[5];
 222         struct addrinfo *ai, *aip, hint = {0};
 223         bool choice;
 224         int i, err;
 225
 226         cp();
 227
 228         myself = new_node();
 229         myself->connection = new_connection();
 230         init_configuration(&myself->connection->config_tree);
 231
 232         asprintf(&myself->hostname, _("MYSELF"));
 233         asprintf(&myself->connection->hostname, _("MYSELF"));
 234
 235         myself->connection->options = 0;
 236         myself->connection->protocol_version = PROT_CURRENT;
 237
 238         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 239                 logger(LOG_ERR, _("Name for tinc daemon required!"));
 240                 return false;
 241         }
 242
 243         if(!check_id(name)) {
 244                 logger(LOG_ERR, _("Invalid name for myself!"));
 245                 free(name);
 246                 return false;
 247         }
 248
 249         myself->name = name;
 250         myself->connection->name = xstrdup(name);
 251
 252         if(!read_connection_config(myself->connection)) {
 253                 logger(LOG_ERR, _("Cannot open host configuration file for myself!"));
 254                 return false;
 255         }
 256
 257         if(!read_rsa_private_key())
 258                 return false;
 259
 260         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 261                 asprintf(&myport, "655");
 262
 263         /* Read in all the subnets specified in the host configuration file */
 264
 265         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 266
 267         while(cfg) {
 268                 if(!get_config_subnet(cfg, &subnet))
 269                         return false;
 270
 271                 subnet_add(myself, subnet);
 272
 273                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 274         }
 275
 276         /* Check some options */
 277
 278         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 279                 myself->options |= OPTION_INDIRECT;
 280
 281         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 282                 myself->options |= OPTION_TCPONLY;
 283
 284         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 285                 myself->options |= OPTION_INDIRECT;
 286
 287         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 288                 myself->options |= OPTION_TCPONLY;
 289
 290         if(get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice) && choice)
 291                 myself->options |= OPTION_PMTU_DISCOVERY;
 292
 293         if(myself->options & OPTION_TCPONLY)
 294                 myself->options |= OPTION_INDIRECT;
 295
 296         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 297
 298         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 299                 if(!strcasecmp(mode, "router"))
 300                         routing_mode = RMODE_ROUTER;
 301                 else if(!strcasecmp(mode, "switch"))
 302                         routing_mode = RMODE_SWITCH;
 303                 else if(!strcasecmp(mode, "hub"))
 304                         routing_mode = RMODE_HUB;
 305                 else {
 306                         logger(LOG_ERR, _("Invalid routing mode!"));
 307                         return false;
 308                 }
 309                 free(mode);
 310         } else
 311                 routing_mode = RMODE_ROUTER;
 312
 313         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 314
 315 #if !defined(SOL_IP) || !defined(IP_TOS)
 316         if(priorityinheritance)
 317                 logger(LOG_WARNING, _("PriorityInheritance not supported on this platform"));
 318 #endif
 319
 320         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 321                 macexpire = 600;
 322
 323         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 324                 if(maxtimeout <= 0) {
 325                         logger(LOG_ERR, _("Bogus maximum timeout!"));
 326                         return false;
 327                 }
 328         } else
 329                 maxtimeout = 900;
 330
 331         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 332                 if(!strcasecmp(afname, "IPv4"))
 333                         addressfamily = AF_INET;
 334                 else if(!strcasecmp(afname, "IPv6"))
 335                         addressfamily = AF_INET6;
 336                 else if(!strcasecmp(afname, "any"))
 337                         addressfamily = AF_UNSPEC;
 338                 else {
 339                         logger(LOG_ERR, _("Invalid address family!"));
 340                         return false;
 341                 }
 342                 free(afname);
 343         }
 344
 345         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 346
 347         /* Generate packet encryption key */
 348
 349         if(get_config_string
 350            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 351                 if(!strcasecmp(cipher, "none")) {
 352                         myself->cipher = NULL;
 353                 } else {
 354                         myself->cipher = EVP_get_cipherbyname(cipher);
 355
 356                         if(!myself->cipher) {
 357                                 logger(LOG_ERR, _("Unrecognized cipher type!"));
 358                                 return false;
 359                         }
 360                 }
 361         } else
 362                 myself->cipher = EVP_bf_cbc();
 363
 364         if(myself->cipher)
 365                 myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 366         else
 367                 myself->keylength = 1;
 368
 369         myself->connection->outcipher = EVP_bf_ofb();
 370
 371         myself->key = xmalloc(myself->keylength);
 372         RAND_pseudo_bytes((unsigned char *)myself->key, myself->keylength);
 373
 374         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 375                 keylifetime = 3600;
 376
 377         keyexpires = now + keylifetime;
 378
 379         if(myself->cipher) {
 380                 EVP_CIPHER_CTX_init(&packet_ctx);
 381                 if(!EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, (unsigned char *)myself->key, (unsigned char *)myself->key + myself->cipher->key_len)) {
 382                         logger(LOG_ERR, _("Error during initialisation of cipher for %s (%s): %s"),
 383                                         myself->name, myself->hostname, ERR_error_string(ERR_get_error(), NULL));
 384                         return false;
 385                 }
 386
 387         }
 388
 389         /* Check if we want to use message authentication codes... */
 390
 391         if(get_config_string
 392            (lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 393                 if(!strcasecmp(digest, "none")) {
 394                         myself->digest = NULL;
 395                 } else {
 396                         myself->digest = EVP_get_digestbyname(digest);
 397
 398                         if(!myself->digest) {
 399                                 logger(LOG_ERR, _("Unrecognized digest type!"));
 400                                 return false;
 401                         }
 402                 }
 403         } else
 404                 myself->digest = EVP_sha1();
 405
 406         myself->connection->outdigest = EVP_sha1();
 407
 408         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"),
 409                 &myself->maclength)) {
 410                 if(myself->digest) {
 411                         if(myself->maclength > myself->digest->md_size) {
 412                                 logger(LOG_ERR, _("MAC length exceeds size of digest!"));
 413                                 return false;
 414                         } else if(myself->maclength < 0) {
 415                                 logger(LOG_ERR, _("Bogus MAC length!"));
 416                                 return false;
 417                         }
 418                 }
 419         } else
 420                 myself->maclength = 4;
 421
 422         myself->connection->outmaclength = 0;
 423
 424         /* Compression */
 425
 426         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"),
 427                 &myself->compression)) {
 428                 if(myself->compression < 0 || myself->compression > 11) {
 429                         logger(LOG_ERR, _("Bogus compression level!"));
 430                         return false;
 431                 }
 432         } else
 433                 myself->compression = 0;
 434
 435         myself->connection->outcompression = 0;
 436
 437         /* Done */
 438
 439         myself->nexthop = myself;
 440         myself->via = myself;
 441         myself->status.reachable = true;
 442         node_add(myself);
 443
 444         graph();
 445
 446         /* Open device */
 447
 448         if(!setup_device())
 449                 return false;
 450
 451         event_set(&device_ev, device_fd, EV_READ|EV_PERSIST,
 452                           handle_device_data, NULL);
 453         if (event_add(&device_ev, NULL) < 0) {
 454                 logger(LOG_ERR, _("event_add failed: %s"), strerror(errno));
 455                 close_device();
 456                 return false;
 457         }
 458
 459         /* Run tinc-up script to further initialize the tap interface */
 460         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 461         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 462         asprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 463         asprintf(&envp[3], "NAME=%s", myself->name);
 464         envp[4] = NULL;
 465
 466         execute_script("tinc-up", envp);
 467
 468         for(i = 0; i < 5; i++)
 469                 free(envp[i]);
 470
 471         /* Run subnet-up scripts for our own subnets */
 472
 473         subnet_update(myself, NULL, true);
 474
 475         /* Open sockets */
 476
 477         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 478
 479         hint.ai_family = addressfamily;
 480         hint.ai_socktype = SOCK_STREAM;
 481         hint.ai_protocol = IPPROTO_TCP;
 482         hint.ai_flags = AI_PASSIVE;
 483
 484         err = getaddrinfo(address, myport, &hint, &ai);
 485
 486         if(err || !ai) {
 487                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
 488                            gai_strerror(err));
 489                 return false;
 490         }
 491
 492         listen_sockets = 0;
 493
 494         for(aip = ai; aip; aip = aip->ai_next) {
 495                 listen_socket[listen_sockets].tcp =
 496                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 497
 498                 if(listen_socket[listen_sockets].tcp < 0)
 499                         continue;
 500
 501                 listen_socket[listen_sockets].udp =
 502                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 503
 504                 if(listen_socket[listen_sockets].udp < 0) {
 505                         close(listen_socket[listen_sockets].tcp);
 506                         continue;
 507                 }
 508
 509                 event_set(&listen_socket[listen_sockets].ev_tcp,
 510                                   listen_socket[listen_sockets].tcp,
 511                                   EV_READ|EV_PERSIST,
 512                                   handle_new_meta_connection, NULL);
 513                 if(event_add(&listen_socket[listen_sockets].ev_tcp, NULL) < 0) {
 514                         logger(LOG_WARNING, _("event_add failed: %s"), strerror(errno));
 515                         close(listen_socket[listen_sockets].tcp);
 516                         close(listen_socket[listen_sockets].udp);
 517                         continue;
 518                 }
 519
 520                 event_set(&listen_socket[listen_sockets].ev_udp,
 521                                   listen_socket[listen_sockets].udp,
 522                                   EV_READ|EV_PERSIST,
 523                                   handle_incoming_vpn_data, NULL);
 524                 if(event_add(&listen_socket[listen_sockets].ev_udp, NULL) < 0) {
 525                         logger(LOG_WARNING, _("event_add failed: %s"), strerror(errno));
 526                         close(listen_socket[listen_sockets].tcp);
 527                         close(listen_socket[listen_sockets].udp);
 528                         event_del(&listen_socket[listen_sockets].ev_tcp);
 529                         continue;
 530                 }
 531
 532                 ifdebug(CONNECTIONS) {
 533                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 534                         logger(LOG_NOTICE, _("Listening on %s"), hostname);
 535                         free(hostname);
 536                 }
 537
 538                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 539                 listen_sockets++;
 540
 541                 if(listen_sockets >= MAXSOCKETS) {
 542                         logger(LOG_WARNING, _("Maximum of %d listening sockets reached"), MAXSOCKETS);
 543                         break;
 544                 }
 545         }
 546
 547         freeaddrinfo(ai);
 548
 549         if(listen_sockets)
 550                 logger(LOG_NOTICE, _("Ready"));
 551         else {
 552                 logger(LOG_ERR, _("Unable to create any listening socket!"));
 553                 return false;
 554         }
 555
 556         return true;
 557 }
 558
 559 /*
 560   setup all initial network connections
 561 */
 562 bool setup_network_connections(void)
 563 {
 564         cp();
 565
 566         now = time(NULL);
 567
 568         init_tevents();
 569         init_connections();
 570         init_subnets();
 571         init_nodes();
 572         init_edges();
 573         init_requests();
 574
 575         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 576                 if(pinginterval < 1) {
 577                         pinginterval = 86400;
 578                 }
 579         } else
 580                 pinginterval = 60;
 581
 582         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 583                 pingtimeout = 5;
 584         if(pingtimeout < 1 || pingtimeout > pinginterval)
 585                 pingtimeout = pinginterval;
 586
 587         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 588                 maxoutbufsize = 4 * MTU;
 589
 590         if(!setup_myself())
 591                 return false;
 592
 593         try_outgoing_connections();
 594
 595         return true;
 596 }
 597
 598 /*
 599   close all open network connections
 600 */
 601 void close_network_connections(void)
 602 {
 603         avl_node_t *node, *next;
 604         connection_t *c;
 605         char *envp[5];
 606         int i;
 607
 608         cp();
 609
 610         for(node = connection_tree->head; node; node = next) {
 611                 next = node->next;
 612                 c = node->data;
 613
 614                 if(c->outgoing) {
 615                         if(c->outgoing->ai)
 616                                 freeaddrinfo(c->outgoing->ai);
 617                         free(c->outgoing->name);
 618                         free(c->outgoing);
 619                         c->outgoing = NULL;
 620                 }
 621
 622                 terminate_connection(c, false);
 623         }
 624
 625         if(myself && myself->connection) {
 626                 subnet_update(myself, NULL, false);
 627                 terminate_connection(myself->connection, false);
 628         }
 629
 630         for(i = 0; i < listen_sockets; i++) {
 631                 event_del(&listen_socket[i].ev_tcp);
 632                 event_del(&listen_socket[i].ev_udp);
 633                 close(listen_socket[i].tcp);
 634                 close(listen_socket[i].udp);
 635         }
 636
 637         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 638         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 639         asprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 640         asprintf(&envp[3], "NAME=%s", myself->name);
 641         envp[4] = NULL;
 642
 643         exit_requests();
 644         exit_edges();
 645         exit_subnets();
 646         exit_nodes();
 647         exit_connections();
 648         exit_tevents();
 649
 650         execute_script("tinc-down", envp);
 651
 652         for(i = 0; i < 4; i++)
 653                 free(envp[i]);
 654
 655         close_device();
 656
 657         return;
 658 }