src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2009 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 along
  17     with this program; if not, write to the Free Software Foundation, Inc.,
  18     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21 #include "system.h"
  22
  23 #include <openssl/pem.h>
  24 #include <openssl/rsa.h>
  25 #include <openssl/rand.h>
  26 #include <openssl/err.h>
  27 #include <openssl/evp.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 bool 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 true;
  67         }
  68
  69         /* Else, check for PublicKeyFile statement and read it */
  70
  71         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  72                 fp = fopen(fname, "r");
  73
  74                 if(!fp) {
  75                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  76                                    fname, strerror(errno));
  77                         free(fname);
  78                         return false;
  79                 }
  80
  81                 free(fname);
  82                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  83                 fclose(fp);
  84
  85                 if(c->rsa_key)
  86                         return true;            /* Woohoo. */
  87
  88                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  89                 fp = fopen(fname, "r");
  90
  91                 if(!fp) {
  92                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
  93                                    fname, strerror(errno));
  94                         free(fname);
  95                         return false;
  96                 }
  97
  98                 free(fname);
  99                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 100                 fclose(fp);
 101
 102                 if(c->rsa_key) {
 103 //                              RSA_blinding_on(c->rsa_key, NULL);
 104                         return true;
 105                 }
 106
 107                 logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 108                            fname, strerror(errno));
 109                 return false;
 110         }
 111
 112         /* Else, check if a harnessed public key is in the config file */
 113
 114         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 115         fp = fopen(fname, "r");
 116
 117         if(fp) {
 118                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 119                 fclose(fp);
 120         }
 121
 122         free(fname);
 123
 124         if(c->rsa_key)
 125                 return true;
 126
 127         /* Try again with PEM_read_RSA_PUBKEY. */
 128
 129         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 130         fp = fopen(fname, "r");
 131
 132         if(fp) {
 133                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 134 //              RSA_blinding_on(c->rsa_key, NULL);
 135                 fclose(fp);
 136         }
 137
 138         free(fname);
 139
 140         if(c->rsa_key)
 141                 return true;
 142
 143         logger(LOG_ERR, _("No public key for %s specified!"), c->name);
 144
 145         return false;
 146 }
 147
 148 bool read_rsa_private_key(void)
 149 {
 150         FILE *fp;
 151         char *fname, *key, *pubkey;
 152         struct stat s;
 153
 154         cp();
 155
 156         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 157                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
 158                         logger(LOG_ERR, _("PrivateKey used but no PublicKey found!"));
 159                         return false;
 160                 }
 161                 myself->connection->rsa_key = RSA_new();
 162 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 163                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 164                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 165                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 166                 free(key);
 167                 free(pubkey);
 168                 return true;
 169         }
 170
 171         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 172                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 173
 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 false;
 181         }
 182
 183 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 184         if(fstat(fileno(fp), &s)) {
 185                 logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"),
 186                                 fname, strerror(errno));
 187                 free(fname);
 188                 return false;
 189         }
 190
 191         if(s.st_mode & ~0100700)
 192                 logger(LOG_WARNING, _("Warning: insecure file permissions for RSA private key file `%s'!"), fname);
 193 #endif
 194
 195         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 196         fclose(fp);
 197
 198         if(!myself->connection->rsa_key) {
 199                 logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 200                            fname, strerror(errno));
 201                 free(fname);
 202                 return false;
 203         }
 204
 205         free(fname);
 206         return true;
 207 }
 208
 209 /*
 210   Configure node_t myself and set up the local sockets (listen only)
 211 */
 212 bool setup_myself(void)
 213 {
 214         config_t *cfg;
 215         subnet_t *subnet;
 216         char *name, *hostname, *mode, *afname, *cipher, *digest;
 217         char *address = NULL;
 218         char *envp[5];
 219         struct addrinfo *ai, *aip, hint = {0};
 220         bool choice;
 221         int i, err;
 222
 223         cp();
 224
 225         myself = new_node();
 226         myself->connection = new_connection();
 227         init_configuration(&myself->connection->config_tree);
 228
 229         xasprintf(&myself->hostname, _("MYSELF"));
 230         xasprintf(&myself->connection->hostname, _("MYSELF"));
 231
 232         myself->connection->options = 0;
 233         myself->connection->protocol_version = PROT_CURRENT;
 234
 235         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 236                 logger(LOG_ERR, _("Name for tinc daemon required!"));
 237                 return false;
 238         }
 239
 240         if(!check_id(name)) {
 241                 logger(LOG_ERR, _("Invalid name for myself!"));
 242                 free(name);
 243                 return false;
 244         }
 245
 246         myself->name = name;
 247         myself->connection->name = xstrdup(name);
 248
 249         if(!read_connection_config(myself->connection)) {
 250                 logger(LOG_ERR, _("Cannot open host configuration file for myself!"));
 251                 return false;
 252         }
 253
 254         if(!read_rsa_private_key())
 255                 return false;
 256
 257         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 258                 xasprintf(&myport, "655");
 259
 260         /* Read in all the subnets specified in the host configuration file */
 261
 262         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 263
 264         while(cfg) {
 265                 if(!get_config_subnet(cfg, &subnet))
 266                         return false;
 267
 268                 subnet_add(myself, subnet);
 269
 270                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 271         }
 272
 273         /* Check some options */
 274
 275         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 276                 myself->options |= OPTION_INDIRECT;
 277
 278         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 279                 myself->options |= OPTION_TCPONLY;
 280
 281         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 282                 myself->options |= OPTION_INDIRECT;
 283
 284         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 285                 myself->options |= OPTION_TCPONLY;
 286
 287         if(myself->options & OPTION_TCPONLY)
 288                 myself->options |= OPTION_INDIRECT;
 289
 290         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 291
 292         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 293                 if(!strcasecmp(mode, "router"))
 294                         routing_mode = RMODE_ROUTER;
 295                 else if(!strcasecmp(mode, "switch"))
 296                         routing_mode = RMODE_SWITCH;
 297                 else if(!strcasecmp(mode, "hub"))
 298                         routing_mode = RMODE_HUB;
 299                 else {
 300                         logger(LOG_ERR, _("Invalid routing mode!"));
 301                         return false;
 302                 }
 303                 free(mode);
 304         } else
 305                 routing_mode = RMODE_ROUTER;
 306
 307         // Enable PMTUDiscovery by default if we are in router mode.
 308
 309         choice = routing_mode == RMODE_ROUTER;
 310         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 311         if(choice)
 312                 myself->options |= OPTION_PMTU_DISCOVERY;
 313
 314         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 315
 316 #if !defined(SOL_IP) || !defined(IP_TOS)
 317         if(priorityinheritance)
 318                 logger(LOG_WARNING, _("%s not supported on this platform"), "PriorityInheritance");
 319 #endif
 320
 321         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 322                 macexpire = 600;
 323
 324         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 325                 if(maxtimeout <= 0) {
 326                         logger(LOG_ERR, _("Bogus maximum timeout!"));
 327                         return false;
 328                 }
 329         } else
 330                 maxtimeout = 900;
 331
 332         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 333                 if(!strcasecmp(afname, "IPv4"))
 334                         addressfamily = AF_INET;
 335                 else if(!strcasecmp(afname, "IPv6"))
 336                         addressfamily = AF_INET6;
 337                 else if(!strcasecmp(afname, "any"))
 338                         addressfamily = AF_UNSPEC;
 339                 else {
 340                         logger(LOG_ERR, _("Invalid address family!"));
 341                         return false;
 342                 }
 343                 free(afname);
 344         }
 345
 346         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 347
 348         /* Generate packet encryption key */
 349
 350         if(get_config_string
 351            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 352                 if(!strcasecmp(cipher, "none")) {
 353                         myself->incipher = NULL;
 354                 } else {
 355                         myself->incipher = EVP_get_cipherbyname(cipher);
 356
 357                         if(!myself->incipher) {
 358                                 logger(LOG_ERR, _("Unrecognized cipher type!"));
 359                                 return false;
 360                         }
 361                 }
 362         } else
 363                 myself->incipher = EVP_aes_256_cbc();
 364
 365         if(myself->incipher)
 366                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 367         else
 368                 myself->inkeylength = 1;
 369
 370         myself->connection->outcipher = EVP_aes_256_ofb();
 371
 372         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 373                 keylifetime = 3600;
 374
 375         keyexpires = now + keylifetime;
 376
 377         /* Check if we want to use message authentication codes... */
 378
 379         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 380                 if(!strcasecmp(digest, "none")) {
 381                         myself->indigest = NULL;
 382                 } else {
 383                         myself->indigest = EVP_get_digestbyname(digest);
 384
 385                         if(!myself->indigest) {
 386                                 logger(LOG_ERR, _("Unrecognized digest type!"));
 387                                 return false;
 388                         }
 389                 }
 390         } else
 391                 myself->indigest = EVP_sha256();
 392
 393         myself->connection->outdigest = EVP_sha256();
 394
 395         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 396                 if(myself->indigest) {
 397                         if(myself->inmaclength > myself->indigest->md_size) {
 398                                 logger(LOG_ERR, _("MAC length exceeds size of digest!"));
 399                                 return false;
 400                         } else if(myself->inmaclength < 0) {
 401                                 logger(LOG_ERR, _("Bogus MAC length!"));
 402                                 return false;
 403                         }
 404                 }
 405         } else
 406                 myself->inmaclength = 4;
 407
 408         myself->connection->outmaclength = 0;
 409
 410         /* Compression */
 411
 412         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 413                 if(myself->incompression < 0 || myself->incompression > 11) {
 414                         logger(LOG_ERR, _("Bogus compression level!"));
 415                         return false;
 416                 }
 417         } else
 418                 myself->incompression = 0;
 419
 420         myself->connection->outcompression = 0;
 421
 422         /* Done */
 423
 424         myself->nexthop = myself;
 425         myself->via = myself;
 426         myself->status.reachable = true;
 427         node_add(myself);
 428
 429         graph();
 430
 431         /* Open device */
 432
 433         if(!setup_device())
 434                 return false;
 435
 436         /* Run tinc-up script to further initialize the tap interface */
 437         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 438         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 439         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 440         xasprintf(&envp[3], "NAME=%s", myself->name);
 441         envp[4] = NULL;
 442
 443         execute_script("tinc-up", envp);
 444
 445         for(i = 0; i < 5; i++)
 446                 free(envp[i]);
 447
 448         /* Run subnet-up scripts for our own subnets */
 449
 450         subnet_update(myself, NULL, true);
 451
 452         /* Open sockets */
 453
 454         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 455
 456         hint.ai_family = addressfamily;
 457         hint.ai_socktype = SOCK_STREAM;
 458         hint.ai_protocol = IPPROTO_TCP;
 459         hint.ai_flags = AI_PASSIVE;
 460
 461         err = getaddrinfo(address, myport, &hint, &ai);
 462
 463         if(err || !ai) {
 464                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
 465                            gai_strerror(err));
 466                 return false;
 467         }
 468
 469         listen_sockets = 0;
 470
 471         for(aip = ai; aip; aip = aip->ai_next) {
 472                 listen_socket[listen_sockets].tcp =
 473                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 474
 475                 if(listen_socket[listen_sockets].tcp < 0)
 476                         continue;
 477
 478                 listen_socket[listen_sockets].udp =
 479                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 480
 481                 if(listen_socket[listen_sockets].udp < 0)
 482                         continue;
 483
 484                 ifdebug(CONNECTIONS) {
 485                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 486                         logger(LOG_NOTICE, _("Listening on %s"), hostname);
 487                         free(hostname);
 488                 }
 489
 490                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 491                 listen_sockets++;
 492         }
 493
 494         freeaddrinfo(ai);
 495
 496         if(listen_sockets)
 497                 logger(LOG_NOTICE, _("Ready"));
 498         else {
 499                 logger(LOG_ERR, _("Unable to create any listening socket!"));
 500                 return false;
 501         }
 502
 503         return true;
 504 }
 505
 506 /*
 507   initialize network
 508 */
 509 bool setup_network(void)
 510 {
 511         cp();
 512
 513         now = time(NULL);
 514
 515         init_events();
 516         init_connections();
 517         init_subnets();
 518         init_nodes();
 519         init_edges();
 520         init_requests();
 521
 522         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 523                 if(pinginterval < 1) {
 524                         pinginterval = 86400;
 525                 }
 526         } else
 527                 pinginterval = 60;
 528
 529         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 530                 pingtimeout = 5;
 531         if(pingtimeout < 1 || pingtimeout > pinginterval)
 532                 pingtimeout = pinginterval;
 533
 534         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 535                 maxoutbufsize = 10 * MTU;
 536
 537         if(!setup_myself())
 538                 return false;
 539
 540         return true;
 541 }
 542
 543 /*
 544   close all open network connections
 545 */
 546 void close_network_connections(void)
 547 {
 548         avl_node_t *node, *next;
 549         connection_t *c;
 550         char *envp[5];
 551         int i;
 552
 553         cp();
 554
 555         for(node = connection_tree->head; node; node = next) {
 556                 next = node->next;
 557                 c = node->data;
 558                 c->outgoing = false;
 559                 terminate_connection(c, false);
 560         }
 561
 562         list_delete_list(outgoing_list);
 563
 564         if(myself && myself->connection) {
 565                 subnet_update(myself, NULL, false);
 566                 terminate_connection(myself->connection, false);
 567                 free_connection(myself->connection);
 568         }
 569
 570         for(i = 0; i < listen_sockets; i++) {
 571                 close(listen_socket[i].tcp);
 572                 close(listen_socket[i].udp);
 573         }
 574
 575         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 576         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 577         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 578         xasprintf(&envp[3], "NAME=%s", myself->name);
 579         envp[4] = NULL;
 580
 581         exit_requests();
 582         exit_edges();
 583         exit_subnets();
 584         exit_nodes();
 585         exit_connections();
 586         exit_events();
 587
 588         execute_script("tinc-down", envp);
 589
 590         if(myport) free(myport);
 591
 592         for(i = 0; i < 4; i++)
 593                 free(envp[i]);
 594
 595         close_device();
 596
 597         return;
 598 }