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

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2009 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
  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 "event.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
  49 bool read_rsa_public_key(connection_t *c)
  50 {
  51         FILE *fp;
  52         char *fname;
  53         char *key;
  54
  55         cp();
  56
  57         if(!c->rsa_key) {
  58                 c->rsa_key = RSA_new();
  59 //              RSA_blinding_on(c->rsa_key, NULL);
  60         }
  61
  62         /* First, check for simple PublicKey statement */
  63
  64         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  65                 BN_hex2bn(&c->rsa_key->n, key);
  66                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  67                 free(key);
  68                 return true;
  69         }
  70
  71         /* Else, check for PublicKeyFile statement and read it */
  72
  73         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &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 false;
  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 true;            /* 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 false;
  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 true;
 107                 }
 108
 109                 logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 110                            fname, strerror(errno));
 111                 return false;
 112         }
 113
 114         /* Else, check if a harnessed public key is in the config file */
 115
 116         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 117         fp = fopen(fname, "r");
 118
 119         if(fp) {
 120                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 121                 fclose(fp);
 122         }
 123
 124         free(fname);
 125
 126         if(c->rsa_key)
 127                 return true;
 128
 129         /* Try again with PEM_read_RSA_PUBKEY. */
 130
 131         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 132         fp = fopen(fname, "r");
 133
 134         if(fp) {
 135                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 136 //              RSA_blinding_on(c->rsa_key, NULL);
 137                 fclose(fp);
 138         }
 139
 140         free(fname);
 141
 142         if(c->rsa_key)
 143                 return true;
 144
 145         logger(LOG_ERR, _("No public key for %s specified!"), c->name);
 146
 147         return false;
 148 }
 149
 150 bool read_rsa_private_key(void)
 151 {
 152         FILE *fp;
 153         char *fname, *key, *pubkey;
 154         struct stat s;
 155
 156         cp();
 157
 158         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 159                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
 160                         logger(LOG_ERR, _("PrivateKey used but no PublicKey found!"));
 161                         return false;
 162                 }
 163                 myself->connection->rsa_key = RSA_new();
 164 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 165                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 166                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 167                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 168                 free(key);
 169                 free(pubkey);
 170                 return true;
 171         }
 172
 173         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 174                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 175
 176         fp = fopen(fname, "r");
 177
 178         if(!fp) {
 179                 logger(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 180                            fname, strerror(errno));
 181                 free(fname);
 182                 return false;
 183         }
 184
 185 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 186         if(fstat(fileno(fp), &s)) {
 187                 logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"),
 188                                 fname, strerror(errno));
 189                 free(fname);
 190                 return false;
 191         }
 192
 193         if(s.st_mode & ~0100700)
 194                 logger(LOG_WARNING, _("Warning: insecure file permissions for RSA private key file `%s'!"), fname);
 195 #endif
 196
 197         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 198         fclose(fp);
 199
 200         if(!myself->connection->rsa_key) {
 201                 logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 202                            fname, strerror(errno));
 203                 free(fname);
 204                 return false;
 205         }
 206
 207         free(fname);
 208         return true;
 209 }
 210
 211 /*
 212   Configure node_t myself and set up the local sockets (listen only)
 213 */
 214 bool setup_myself(void)
 215 {
 216         config_t *cfg;
 217         subnet_t *subnet;
 218         char *name, *hostname, *mode, *afname, *cipher, *digest;
 219         char *address = NULL;
 220         char *envp[5];
 221         struct addrinfo *ai, *aip, hint = {0};
 222         bool choice;
 223         int i, err;
 224
 225         cp();
 226
 227         myself = new_node();
 228         myself->connection = new_connection();
 229         init_configuration(&myself->connection->config_tree);
 230
 231         xasprintf(&myself->hostname, _("MYSELF"));
 232         xasprintf(&myself->connection->hostname, _("MYSELF"));
 233
 234         myself->connection->options = 0;
 235         myself->connection->protocol_version = PROT_CURRENT;
 236
 237         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 238                 logger(LOG_ERR, _("Name for tinc daemon required!"));
 239                 return false;
 240         }
 241
 242         if(!check_id(name)) {
 243                 logger(LOG_ERR, _("Invalid name for myself!"));
 244                 free(name);
 245                 return false;
 246         }
 247
 248         myself->name = name;
 249         myself->connection->name = xstrdup(name);
 250
 251         if(!read_connection_config(myself->connection)) {
 252                 logger(LOG_ERR, _("Cannot open host configuration file for myself!"));
 253                 return false;
 254         }
 255
 256         if(!read_rsa_private_key())
 257                 return false;
 258
 259         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 260                 xasprintf(&myport, "655");
 261
 262         /* Read in all the subnets specified in the host configuration file */
 263
 264         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 265
 266         while(cfg) {
 267                 if(!get_config_subnet(cfg, &subnet))
 268                         return false;
 269
 270                 subnet_add(myself, subnet);
 271
 272                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 273         }
 274
 275         /* Check some options */
 276
 277         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 278                 myself->options |= OPTION_INDIRECT;
 279
 280         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 281                 myself->options |= OPTION_TCPONLY;
 282
 283         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 284                 myself->options |= OPTION_INDIRECT;
 285
 286         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 287                 myself->options |= OPTION_TCPONLY;
 288
 289         if(myself->options & OPTION_TCPONLY)
 290                 myself->options |= OPTION_INDIRECT;
 291
 292         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 293
 294         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 295                 if(!strcasecmp(mode, "router"))
 296                         routing_mode = RMODE_ROUTER;
 297                 else if(!strcasecmp(mode, "switch"))
 298                         routing_mode = RMODE_SWITCH;
 299                 else if(!strcasecmp(mode, "hub"))
 300                         routing_mode = RMODE_HUB;
 301                 else {
 302                         logger(LOG_ERR, _("Invalid routing mode!"));
 303                         return false;
 304                 }
 305                 free(mode);
 306         } else
 307                 routing_mode = RMODE_ROUTER;
 308
 309         // Enable PMTUDiscovery by default if we are in router mode.
 310
 311         choice = routing_mode == RMODE_ROUTER;
 312         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 313         if(choice)
 314                 myself->options |= OPTION_PMTU_DISCOVERY;
 315
 316         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 317
 318 #if !defined(SOL_IP) || !defined(IP_TOS)
 319         if(priorityinheritance)
 320                 logger(LOG_WARNING, _("%s not supported on this platform"), "PriorityInheritance");
 321 #endif
 322
 323         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 324                 macexpire = 600;
 325
 326         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 327                 if(maxtimeout <= 0) {
 328                         logger(LOG_ERR, _("Bogus maximum timeout!"));
 329                         return false;
 330                 }
 331         } else
 332                 maxtimeout = 900;
 333
 334         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 335                 if(!strcasecmp(afname, "IPv4"))
 336                         addressfamily = AF_INET;
 337                 else if(!strcasecmp(afname, "IPv6"))
 338                         addressfamily = AF_INET6;
 339                 else if(!strcasecmp(afname, "any"))
 340                         addressfamily = AF_UNSPEC;
 341                 else {
 342                         logger(LOG_ERR, _("Invalid address family!"));
 343                         return false;
 344                 }
 345                 free(afname);
 346         }
 347
 348         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 349
 350         /* Generate packet encryption key */
 351
 352         if(get_config_string
 353            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 354                 if(!strcasecmp(cipher, "none")) {
 355                         myself->incipher = NULL;
 356                 } else {
 357                         myself->incipher = EVP_get_cipherbyname(cipher);
 358
 359                         if(!myself->incipher) {
 360                                 logger(LOG_ERR, _("Unrecognized cipher type!"));
 361                                 return false;
 362                         }
 363                 }
 364         } else
 365                 myself->incipher = EVP_aes_256_cbc();
 366
 367         if(myself->incipher)
 368                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 369         else
 370                 myself->inkeylength = 1;
 371
 372         myself->connection->outcipher = EVP_aes_256_ofb();
 373
 374         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 375                 keylifetime = 3600;
 376
 377         keyexpires = now + keylifetime;
 378
 379         /* Check if we want to use message authentication codes... */
 380
 381         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 382                 if(!strcasecmp(digest, "none")) {
 383                         myself->indigest = NULL;
 384                 } else {
 385                         myself->indigest = EVP_get_digestbyname(digest);
 386
 387                         if(!myself->indigest) {
 388                                 logger(LOG_ERR, _("Unrecognized digest type!"));
 389                                 return false;
 390                         }
 391                 }
 392         } else
 393                 myself->indigest = EVP_sha256();
 394
 395         myself->connection->outdigest = EVP_sha256();
 396
 397         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 398                 if(myself->indigest) {
 399                         if(myself->inmaclength > myself->indigest->md_size) {
 400                                 logger(LOG_ERR, _("MAC length exceeds size of digest!"));
 401                                 return false;
 402                         } else if(myself->inmaclength < 0) {
 403                                 logger(LOG_ERR, _("Bogus MAC length!"));
 404                                 return false;
 405                         }
 406                 }
 407         } else
 408                 myself->inmaclength = 4;
 409
 410         myself->connection->outmaclength = 0;
 411
 412         /* Compression */
 413
 414         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 415                 if(myself->incompression < 0 || myself->incompression > 11) {
 416                         logger(LOG_ERR, _("Bogus compression level!"));
 417                         return false;
 418                 }
 419         } else
 420                 myself->incompression = 0;
 421
 422         myself->connection->outcompression = 0;
 423
 424         /* Done */
 425
 426         myself->nexthop = myself;
 427         myself->via = myself;
 428         myself->status.reachable = true;
 429         node_add(myself);
 430
 431         graph();
 432
 433         /* Open device */
 434
 435         if(!setup_device())
 436                 return false;
 437
 438         /* Run tinc-up script to further initialize the tap interface */
 439         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 440         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 441         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 442         xasprintf(&envp[3], "NAME=%s", myself->name);
 443         envp[4] = NULL;
 444
 445         execute_script("tinc-up", envp);
 446
 447         for(i = 0; i < 5; i++)
 448                 free(envp[i]);
 449
 450         /* Run subnet-up scripts for our own subnets */
 451
 452         subnet_update(myself, NULL, true);
 453
 454         /* Open sockets */
 455
 456         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 457
 458         hint.ai_family = addressfamily;
 459         hint.ai_socktype = SOCK_STREAM;
 460         hint.ai_protocol = IPPROTO_TCP;
 461         hint.ai_flags = AI_PASSIVE;
 462
 463         err = getaddrinfo(address, myport, &hint, &ai);
 464
 465         if(err || !ai) {
 466                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
 467                            gai_strerror(err));
 468                 return false;
 469         }
 470
 471         listen_sockets = 0;
 472
 473         for(aip = ai; aip; aip = aip->ai_next) {
 474                 listen_socket[listen_sockets].tcp =
 475                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 476
 477                 if(listen_socket[listen_sockets].tcp < 0)
 478                         continue;
 479
 480                 listen_socket[listen_sockets].udp =
 481                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 482
 483                 if(listen_socket[listen_sockets].udp < 0)
 484                         continue;
 485
 486                 ifdebug(CONNECTIONS) {
 487                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 488                         logger(LOG_NOTICE, _("Listening on %s"), hostname);
 489                         free(hostname);
 490                 }
 491
 492                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 493                 listen_sockets++;
 494         }
 495
 496         freeaddrinfo(ai);
 497
 498         if(listen_sockets)
 499                 logger(LOG_NOTICE, _("Ready"));
 500         else {
 501                 logger(LOG_ERR, _("Unable to create any listening socket!"));
 502                 return false;
 503         }
 504
 505         return true;
 506 }
 507
 508 /*
 509   initialize network
 510 */
 511 bool setup_network(void)
 512 {
 513         cp();
 514
 515         now = time(NULL);
 516
 517         init_events();
 518         init_connections();
 519         init_subnets();
 520         init_nodes();
 521         init_edges();
 522         init_requests();
 523
 524         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 525                 if(pinginterval < 1) {
 526                         pinginterval = 86400;
 527                 }
 528         } else
 529                 pinginterval = 60;
 530
 531         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 532                 pingtimeout = 5;
 533         if(pingtimeout < 1 || pingtimeout > pinginterval)
 534                 pingtimeout = pinginterval;
 535
 536         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 537                 maxoutbufsize = 10 * MTU;
 538
 539         if(!setup_myself())
 540                 return false;
 541
 542         return true;
 543 }
 544
 545 /*
 546   close all open network connections
 547 */
 548 void close_network_connections(void)
 549 {
 550         avl_node_t *node, *next;
 551         connection_t *c;
 552         char *envp[5];
 553         int i;
 554
 555         cp();
 556
 557         for(node = connection_tree->head; node; node = next) {
 558                 next = node->next;
 559                 c = node->data;
 560                 c->outgoing = false;
 561                 terminate_connection(c, false);
 562         }
 563
 564         list_delete_list(outgoing_list);
 565
 566         if(myself && myself->connection) {
 567                 subnet_update(myself, NULL, false);
 568                 terminate_connection(myself->connection, false);
 569                 free_connection(myself->connection);
 570         }
 571
 572         for(i = 0; i < listen_sockets; i++) {
 573                 close(listen_socket[i].tcp);
 574                 close(listen_socket[i].udp);
 575         }
 576
 577         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 578         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 579         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 580         xasprintf(&envp[3], "NAME=%s", myself->name);
 581         envp[4] = NULL;
 582
 583         exit_requests();
 584         exit_edges();
 585         exit_subnets();
 586         exit_nodes();
 587         exit_connections();
 588         exit_events();
 589
 590         execute_script("tinc-down", envp);
 591
 592         if(myport) free(myport);
 593
 594         for(i = 0; i < 4; i++)
 595                 free(envp[i]);
 596
 597         close_device();
 598
 599         return;
 600 }