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

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2010 Guus Sliepen <guus@tinc-vpn.org>
   5                   2006      Scott Lamb <slamb@slamb.org>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License along
  18     with this program; if not, write to the Free Software Foundation, Inc.,
  19     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20 */
  21
  22 #include "system.h"
  23
  24 #include <openssl/pem.h>
  25 #include <openssl/rsa.h>
  26 #include <openssl/rand.h>
  27 #include <openssl/err.h>
  28 #include <openssl/evp.h>
  29
  30 #include "avl_tree.h"
  31 #include "conf.h"
  32 #include "connection.h"
  33 #include "device.h"
  34 #include "event.h"
  35 #include "graph.h"
  36 #include "logger.h"
  37 #include "net.h"
  38 #include "netutl.h"
  39 #include "process.h"
  40 #include "protocol.h"
  41 #include "route.h"
  42 #include "subnet.h"
  43 #include "utils.h"
  44 #include "xalloc.h"
  45
  46 char *myport;
  47
  48 bool read_rsa_public_key(connection_t *c) {
  49         FILE *fp;
  50         char *fname;
  51         char *key;
  52
  53         if(!c->rsa_key) {
  54                 c->rsa_key = RSA_new();
  55 //              RSA_blinding_on(c->rsa_key, NULL);
  56         }
  57
  58         /* First, check for simple PublicKey statement */
  59
  60         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  61                 BN_hex2bn(&c->rsa_key->n, key);
  62                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  63                 free(key);
  64                 return true;
  65         }
  66
  67         /* Else, check for PublicKeyFile statement and read it */
  68
  69         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  70                 fp = fopen(fname, "r");
  71
  72                 if(!fp) {
  73                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  74                                    fname, strerror(errno));
  75                         free(fname);
  76                         return false;
  77                 }
  78
  79                 free(fname);
  80                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  81                 fclose(fp);
  82
  83                 if(c->rsa_key)
  84                         return true;            /* Woohoo. */
  85
  86                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  87                 fp = fopen(fname, "r");
  88
  89                 if(!fp) {
  90                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  91                                    fname, strerror(errno));
  92                         free(fname);
  93                         return false;
  94                 }
  95
  96                 free(fname);
  97                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
  98                 fclose(fp);
  99
 100                 if(c->rsa_key) {
 101 //                              RSA_blinding_on(c->rsa_key, NULL);
 102                         return true;
 103                 }
 104
 105                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s",
 106                            fname, strerror(errno));
 107                 return false;
 108         }
 109
 110         /* Else, check if a harnessed public key is in the config file */
 111
 112         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 113         fp = fopen(fname, "r");
 114
 115         if(fp) {
 116                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 117                 fclose(fp);
 118         }
 119
 120         free(fname);
 121
 122         if(c->rsa_key)
 123                 return true;
 124
 125         /* Try again with PEM_read_RSA_PUBKEY. */
 126
 127         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 128         fp = fopen(fname, "r");
 129
 130         if(fp) {
 131                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 132 //              RSA_blinding_on(c->rsa_key, NULL);
 133                 fclose(fp);
 134         }
 135
 136         free(fname);
 137
 138         if(c->rsa_key)
 139                 return true;
 140
 141         logger(LOG_ERR, "No public key for %s specified!", c->name);
 142
 143         return false;
 144 }
 145
 146 bool read_rsa_private_key(void) {
 147         FILE *fp;
 148         char *fname, *key, *pubkey;
 149         struct stat s;
 150
 151         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 152                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
 153                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
 154                         return false;
 155                 }
 156                 myself->connection->rsa_key = RSA_new();
 157 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 158                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 159                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 160                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 161                 free(key);
 162                 free(pubkey);
 163                 return true;
 164         }
 165
 166         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 167                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 168
 169         fp = fopen(fname, "r");
 170
 171         if(!fp) {
 172                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 173                            fname, strerror(errno));
 174                 free(fname);
 175                 return false;
 176         }
 177
 178 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 179         if(fstat(fileno(fp), &s)) {
 180                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
 181                                 fname, strerror(errno));
 182                 free(fname);
 183                 return false;
 184         }
 185
 186         if(s.st_mode & ~0100700)
 187                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 188 #endif
 189
 190         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 191         fclose(fp);
 192
 193         if(!myself->connection->rsa_key) {
 194                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s",
 195                            fname, strerror(errno));
 196                 free(fname);
 197                 return false;
 198         }
 199
 200         free(fname);
 201         return true;
 202 }
 203
 204 /*
 205   Read Subnets from all host config files
 206 */
 207 static void load_all_subnets(void) {
 208         DIR *dir;
 209         struct dirent *ent;
 210         char *dname;
 211         char *fname;
 212         avl_tree_t *config_tree;
 213         config_t *cfg;
 214         subnet_t *s;
 215         node_t *n;
 216         bool result;
 217
 218         xasprintf(&dname, "%s/hosts", confbase);
 219         dir = opendir(dname);
 220         if(!dir) {
 221                 logger(LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 222                 free(dname);
 223                 return;
 224         }
 225
 226         while((ent = readdir(dir))) {
 227                 if(!check_id(ent->d_name))
 228                         continue;
 229
 230                 n = lookup_node(ent->d_name);
 231                 if(n)
 232                         continue;
 233
 234                 #ifdef _DIRENT_HAVE_D_TYPE
 235                 //if(ent->d_type != DT_REG)
 236                 //      continue;
 237                 #endif
 238
 239                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 240                 init_configuration(&config_tree);
 241                 result = read_config_file(config_tree, fname);
 242                 free(fname);
 243                 if(!result)
 244                         continue;
 245
 246                 n = new_node();
 247                 n->name = xstrdup(ent->d_name);
 248                 node_add(n);
 249
 250                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
 251                         if(!get_config_subnet(cfg, &s))
 252                                 continue;
 253
 254                         subnet_add(n, s);
 255                 }
 256
 257                 exit_configuration(&config_tree);
 258         }
 259
 260         closedir(dir);
 261 }
 262
 263 /*
 264   Configure node_t myself and set up the local sockets (listen only)
 265 */
 266 bool setup_myself(void) {
 267         config_t *cfg;
 268         subnet_t *subnet;
 269         char *name, *hostname, *mode, *afname, *cipher, *digest;
 270         char *address = NULL;
 271         char *envp[5];
 272         struct addrinfo *ai, *aip, hint = {0};
 273         bool choice;
 274         int i, err;
 275
 276         myself = new_node();
 277         myself->connection = new_connection();
 278         init_configuration(&myself->connection->config_tree);
 279
 280         myself->hostname = xstrdup("MYSELF");
 281         myself->connection->hostname = xstrdup("MYSELF");
 282
 283         myself->connection->options = 0;
 284         myself->connection->protocol_version = PROT_CURRENT;
 285
 286         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 287                 logger(LOG_ERR, "Name for tinc daemon required!");
 288                 return false;
 289         }
 290
 291         if(!check_id(name)) {
 292                 logger(LOG_ERR, "Invalid name for myself!");
 293                 free(name);
 294                 return false;
 295         }
 296
 297         myself->name = name;
 298         myself->connection->name = xstrdup(name);
 299
 300         if(!read_connection_config(myself->connection)) {
 301                 logger(LOG_ERR, "Cannot open host configuration file for myself!");
 302                 return false;
 303         }
 304
 305         if(!read_rsa_private_key())
 306                 return false;
 307
 308         if(!get_config_string(lookup_config(config_tree, "Port"), &myport)
 309                         && !get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 310                 myport = xstrdup("655");
 311
 312         if(!atoi(myport)) {
 313                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 314                 sockaddr_t sa;
 315                 if(!ai || !ai->ai_addr)
 316                         return false;
 317                 free(myport);
 318                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 319                 sockaddr2str(&sa, NULL, &myport);
 320         }
 321
 322         /* Read in all the subnets specified in the host configuration file */
 323
 324         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 325
 326         while(cfg) {
 327                 if(!get_config_subnet(cfg, &subnet))
 328                         return false;
 329
 330                 subnet_add(myself, subnet);
 331
 332                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 333         }
 334
 335         /* Check some options */
 336
 337         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 338                 myself->options |= OPTION_INDIRECT;
 339
 340         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 341                 myself->options |= OPTION_TCPONLY;
 342
 343         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 344                 myself->options |= OPTION_INDIRECT;
 345
 346         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 347                 myself->options |= OPTION_TCPONLY;
 348
 349         if(myself->options & OPTION_TCPONLY)
 350                 myself->options |= OPTION_INDIRECT;
 351
 352         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 353         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 354         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 355         strictsubnets |= tunnelserver;
 356
 357         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 358                 if(!strcasecmp(mode, "router"))
 359                         routing_mode = RMODE_ROUTER;
 360                 else if(!strcasecmp(mode, "switch"))
 361                         routing_mode = RMODE_SWITCH;
 362                 else if(!strcasecmp(mode, "hub"))
 363                         routing_mode = RMODE_HUB;
 364                 else {
 365                         logger(LOG_ERR, "Invalid routing mode!");
 366                         return false;
 367                 }
 368                 free(mode);
 369         }
 370
 371         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 372                 if(!strcasecmp(mode, "off"))
 373                         forwarding_mode = FMODE_OFF;
 374                 else if(!strcasecmp(mode, "internal"))
 375                         forwarding_mode = FMODE_INTERNAL;
 376                 else if(!strcasecmp(mode, "kernel"))
 377                         forwarding_mode = FMODE_KERNEL;
 378                 else {
 379                         logger(LOG_ERR, "Invalid forwarding mode!");
 380                         return false;
 381                 }
 382                 free(mode);
 383         }
 384
 385         choice = true;
 386         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 387         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 388         if(choice)
 389                 myself->options |= OPTION_PMTU_DISCOVERY;
 390
 391         choice = true;
 392         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 393         get_config_bool(lookup_config(myself->connection->config_tree, "ClampMSS"), &choice);
 394         if(choice)
 395                 myself->options |= OPTION_CLAMP_MSS;
 396
 397         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 398
 399 #if !defined(SOL_IP) || !defined(IP_TOS)
 400         if(priorityinheritance)
 401                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 402 #endif
 403
 404         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 405                 macexpire = 600;
 406
 407         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 408                 if(maxtimeout <= 0) {
 409                         logger(LOG_ERR, "Bogus maximum timeout!");
 410                         return false;
 411                 }
 412         } else
 413                 maxtimeout = 900;
 414
 415         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 416                 if(!strcasecmp(afname, "IPv4"))
 417                         addressfamily = AF_INET;
 418                 else if(!strcasecmp(afname, "IPv6"))
 419                         addressfamily = AF_INET6;
 420                 else if(!strcasecmp(afname, "any"))
 421                         addressfamily = AF_UNSPEC;
 422                 else {
 423                         logger(LOG_ERR, "Invalid address family!");
 424                         return false;
 425                 }
 426                 free(afname);
 427         }
 428
 429         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 430
 431         /* Generate packet encryption key */
 432
 433         if(get_config_string
 434            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 435                 if(!strcasecmp(cipher, "none")) {
 436                         myself->incipher = NULL;
 437                 } else {
 438                         myself->incipher = EVP_get_cipherbyname(cipher);
 439
 440                         if(!myself->incipher) {
 441                                 logger(LOG_ERR, "Unrecognized cipher type!");
 442                                 return false;
 443                         }
 444                 }
 445         } else
 446                 myself->incipher = EVP_bf_cbc();
 447
 448         if(myself->incipher)
 449                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 450         else
 451                 myself->inkeylength = 1;
 452
 453         myself->connection->outcipher = EVP_bf_ofb();
 454
 455         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 456                 keylifetime = 3600;
 457
 458         keyexpires = now + keylifetime;
 459
 460         /* Check if we want to use message authentication codes... */
 461
 462         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 463                 if(!strcasecmp(digest, "none")) {
 464                         myself->indigest = NULL;
 465                 } else {
 466                         myself->indigest = EVP_get_digestbyname(digest);
 467
 468                         if(!myself->indigest) {
 469                                 logger(LOG_ERR, "Unrecognized digest type!");
 470                                 return false;
 471                         }
 472                 }
 473         } else
 474                 myself->indigest = EVP_sha1();
 475
 476         myself->connection->outdigest = EVP_sha1();
 477
 478         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 479                 if(myself->indigest) {
 480                         if(myself->inmaclength > myself->indigest->md_size) {
 481                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 482                                 return false;
 483                         } else if(myself->inmaclength < 0) {
 484                                 logger(LOG_ERR, "Bogus MAC length!");
 485                                 return false;
 486                         }
 487                 }
 488         } else
 489                 myself->inmaclength = 4;
 490
 491         myself->connection->outmaclength = 0;
 492
 493         /* Compression */
 494
 495         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 496                 if(myself->incompression < 0 || myself->incompression > 11) {
 497                         logger(LOG_ERR, "Bogus compression level!");
 498                         return false;
 499                 }
 500         } else
 501                 myself->incompression = 0;
 502
 503         myself->connection->outcompression = 0;
 504
 505         /* Done */
 506
 507         myself->nexthop = myself;
 508         myself->via = myself;
 509         myself->status.reachable = true;
 510         node_add(myself);
 511
 512         graph();
 513
 514         if(strictsubnets)
 515                 load_all_subnets();
 516
 517         /* Open device */
 518
 519         if(!setup_device())
 520                 return false;
 521
 522         /* Run tinc-up script to further initialize the tap interface */
 523         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 524         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 525         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 526         xasprintf(&envp[3], "NAME=%s", myself->name);
 527         envp[4] = NULL;
 528
 529         execute_script("tinc-up", envp);
 530
 531         for(i = 0; i < 5; i++)
 532                 free(envp[i]);
 533
 534         /* Run subnet-up scripts for our own subnets */
 535
 536         subnet_update(myself, NULL, true);
 537
 538         /* Open sockets */
 539
 540         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 541
 542         hint.ai_family = addressfamily;
 543         hint.ai_socktype = SOCK_STREAM;
 544         hint.ai_protocol = IPPROTO_TCP;
 545         hint.ai_flags = AI_PASSIVE;
 546
 547         err = getaddrinfo(address, myport, &hint, &ai);
 548
 549         if(err || !ai) {
 550                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 551                            gai_strerror(err));
 552                 return false;
 553         }
 554
 555         listen_sockets = 0;
 556
 557         for(aip = ai; aip; aip = aip->ai_next) {
 558                 listen_socket[listen_sockets].tcp =
 559                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 560
 561                 if(listen_socket[listen_sockets].tcp < 0)
 562                         continue;
 563
 564                 listen_socket[listen_sockets].udp =
 565                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 566
 567                 if(listen_socket[listen_sockets].udp < 0)
 568                         continue;
 569
 570                 ifdebug(CONNECTIONS) {
 571                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 572                         logger(LOG_NOTICE, "Listening on %s", hostname);
 573                         free(hostname);
 574                 }
 575
 576                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 577                 listen_sockets++;
 578         }
 579
 580         freeaddrinfo(ai);
 581
 582         if(listen_sockets)
 583                 logger(LOG_NOTICE, "Ready");
 584         else {
 585                 logger(LOG_ERR, "Unable to create any listening socket!");
 586                 return false;
 587         }
 588
 589         return true;
 590 }
 591
 592 /*
 593   initialize network
 594 */
 595 bool setup_network(void) {
 596         now = time(NULL);
 597
 598         init_events();
 599         init_connections();
 600         init_subnets();
 601         init_nodes();
 602         init_edges();
 603         init_requests();
 604
 605         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 606                 if(pinginterval < 1) {
 607                         pinginterval = 86400;
 608                 }
 609         } else
 610                 pinginterval = 60;
 611
 612         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 613                 pingtimeout = 5;
 614         if(pingtimeout < 1 || pingtimeout > pinginterval)
 615                 pingtimeout = pinginterval;
 616
 617         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 618                 maxoutbufsize = 10 * MTU;
 619
 620         if(!setup_myself())
 621                 return false;
 622
 623         return true;
 624 }
 625
 626 /*
 627   close all open network connections
 628 */
 629 void close_network_connections(void) {
 630         avl_node_t *node, *next;
 631         connection_t *c;
 632         char *envp[5];
 633         int i;
 634
 635         for(node = connection_tree->head; node; node = next) {
 636                 next = node->next;
 637                 c = node->data;
 638                 c->outgoing = NULL;
 639                 terminate_connection(c, false);
 640         }
 641
 642         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
 643                 outgoing_t *outgoing = node->data;
 644
 645                 if(outgoing->event)
 646                         event_del(outgoing->event);
 647         }
 648
 649         list_delete_list(outgoing_list);
 650
 651         if(myself && myself->connection) {
 652                 subnet_update(myself, NULL, false);
 653                 terminate_connection(myself->connection, false);
 654                 free_connection(myself->connection);
 655         }
 656
 657         for(i = 0; i < listen_sockets; i++) {
 658                 close(listen_socket[i].tcp);
 659                 close(listen_socket[i].udp);
 660         }
 661
 662         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 663         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 664         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 665         xasprintf(&envp[3], "NAME=%s", myself->name);
 666         envp[4] = NULL;
 667
 668         exit_requests();
 669         exit_edges();
 670         exit_subnets();
 671         exit_nodes();
 672         exit_connections();
 673         exit_events();
 674
 675         execute_script("tinc-down", envp);
 676
 677         if(myport) free(myport);
 678
 679         for(i = 0; i < 4; i++)
 680                 free(envp[i]);
 681
 682         close_device();
 683
 684         return;
 685 }