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 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         FILE *fp;
  49         char *fname;
  50         char *key;
  51
  52         if(!c->rsa_key) {
  53                 c->rsa_key = RSA_new();
  54 //              RSA_blinding_on(c->rsa_key, NULL);
  55         }
  56
  57         /* First, check for simple PublicKey statement */
  58
  59         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  60                 BN_hex2bn(&c->rsa_key->n, key);
  61                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  62                 free(key);
  63                 return true;
  64         }
  65
  66         /* Else, check for PublicKeyFile statement and read it */
  67
  68         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  69                 fp = fopen(fname, "r");
  70
  71                 if(!fp) {
  72                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  73                                    fname, strerror(errno));
  74                         free(fname);
  75                         return false;
  76                 }
  77
  78                 free(fname);
  79                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  80                 fclose(fp);
  81
  82                 if(c->rsa_key)
  83                         return true;            /* Woohoo. */
  84
  85                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  86                 fp = fopen(fname, "r");
  87
  88                 if(!fp) {
  89                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  90                                    fname, strerror(errno));
  91                         free(fname);
  92                         return false;
  93                 }
  94
  95                 free(fname);
  96                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
  97                 fclose(fp);
  98
  99                 if(c->rsa_key) {
 100 //                              RSA_blinding_on(c->rsa_key, NULL);
 101                         return true;
 102                 }
 103
 104                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s",
 105                            fname, strerror(errno));
 106                 return false;
 107         }
 108
 109         /* Else, check if a harnessed public key is in the config file */
 110
 111         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 112         fp = fopen(fname, "r");
 113
 114         if(fp) {
 115                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 116                 fclose(fp);
 117         }
 118
 119         free(fname);
 120
 121         if(c->rsa_key)
 122                 return true;
 123
 124         /* Try again with PEM_read_RSA_PUBKEY. */
 125
 126         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 127         fp = fopen(fname, "r");
 128
 129         if(fp) {
 130                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 131 //              RSA_blinding_on(c->rsa_key, NULL);
 132                 fclose(fp);
 133         }
 134
 135         free(fname);
 136
 137         if(c->rsa_key)
 138                 return true;
 139
 140         logger(LOG_ERR, "No public key for %s specified!", c->name);
 141
 142         return false;
 143 }
 144
 145 bool read_rsa_private_key(void) {
 146         FILE *fp;
 147         char *fname, *key, *pubkey;
 148         struct stat s;
 149
 150         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 151                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
 152                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
 153                         return false;
 154                 }
 155                 myself->connection->rsa_key = RSA_new();
 156 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 157                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 158                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 159                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 160                 free(key);
 161                 free(pubkey);
 162                 return true;
 163         }
 164
 165         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 166                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 167
 168         fp = fopen(fname, "r");
 169
 170         if(!fp) {
 171                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 172                            fname, strerror(errno));
 173                 free(fname);
 174                 return false;
 175         }
 176
 177 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 178         if(fstat(fileno(fp), &s)) {
 179                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
 180                                 fname, strerror(errno));
 181                 free(fname);
 182                 return false;
 183         }
 184
 185         if(s.st_mode & ~0100700)
 186                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 187 #endif
 188
 189         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 190         fclose(fp);
 191
 192         if(!myself->connection->rsa_key) {
 193                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s",
 194                            fname, strerror(errno));
 195                 free(fname);
 196                 return false;
 197         }
 198
 199         free(fname);
 200         return true;
 201 }
 202
 203 /*
 204   Configure node_t myself and set up the local sockets (listen only)
 205 */
 206 bool setup_myself(void) {
 207         config_t *cfg;
 208         subnet_t *subnet;
 209         char *name, *hostname, *mode, *afname, *cipher, *digest;
 210         char *address = NULL;
 211         char *envp[5];
 212         struct addrinfo *ai, *aip, hint = {0};
 213         bool choice;
 214         int i, err;
 215
 216         myself = new_node();
 217         myself->connection = new_connection();
 218         init_configuration(&myself->connection->config_tree);
 219
 220         xasprintf(&myself->hostname, "MYSELF");
 221         xasprintf(&myself->connection->hostname, "MYSELF");
 222
 223         myself->connection->options = 0;
 224         myself->connection->protocol_version = PROT_CURRENT;
 225
 226         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 227                 logger(LOG_ERR, "Name for tinc daemon required!");
 228                 return false;
 229         }
 230
 231         if(!check_id(name)) {
 232                 logger(LOG_ERR, "Invalid name for myself!");
 233                 free(name);
 234                 return false;
 235         }
 236
 237         myself->name = name;
 238         myself->connection->name = xstrdup(name);
 239
 240         if(!read_connection_config(myself->connection)) {
 241                 logger(LOG_ERR, "Cannot open host configuration file for myself!");
 242                 return false;
 243         }
 244
 245         if(!read_rsa_private_key())
 246                 return false;
 247
 248         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 249                 xasprintf(&myport, "655");
 250
 251         /* Read in all the subnets specified in the host configuration file */
 252
 253         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 254
 255         while(cfg) {
 256                 if(!get_config_subnet(cfg, &subnet))
 257                         return false;
 258
 259                 subnet_add(myself, subnet);
 260
 261                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 262         }
 263
 264         /* Check some options */
 265
 266         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 267                 myself->options |= OPTION_INDIRECT;
 268
 269         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 270                 myself->options |= OPTION_TCPONLY;
 271
 272         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 273                 myself->options |= OPTION_INDIRECT;
 274
 275         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 276                 myself->options |= OPTION_TCPONLY;
 277
 278         if(myself->options & OPTION_TCPONLY)
 279                 myself->options |= OPTION_INDIRECT;
 280
 281         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 282
 283         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 284                 if(!strcasecmp(mode, "router"))
 285                         routing_mode = RMODE_ROUTER;
 286                 else if(!strcasecmp(mode, "switch"))
 287                         routing_mode = RMODE_SWITCH;
 288                 else if(!strcasecmp(mode, "hub"))
 289                         routing_mode = RMODE_HUB;
 290                 else {
 291                         logger(LOG_ERR, "Invalid routing mode!");
 292                         return false;
 293                 }
 294                 free(mode);
 295         } else
 296                 routing_mode = RMODE_ROUTER;
 297
 298         // Enable PMTUDiscovery by default if we are in router mode.
 299
 300         choice = routing_mode == RMODE_ROUTER;
 301         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 302         if(choice)
 303                 myself->options |= OPTION_PMTU_DISCOVERY;
 304
 305         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 306
 307 #if !defined(SOL_IP) || !defined(IP_TOS)
 308         if(priorityinheritance)
 309                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 310 #endif
 311
 312         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 313                 macexpire = 600;
 314
 315         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 316                 if(maxtimeout <= 0) {
 317                         logger(LOG_ERR, "Bogus maximum timeout!");
 318                         return false;
 319                 }
 320         } else
 321                 maxtimeout = 900;
 322
 323         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 324                 if(!strcasecmp(afname, "IPv4"))
 325                         addressfamily = AF_INET;
 326                 else if(!strcasecmp(afname, "IPv6"))
 327                         addressfamily = AF_INET6;
 328                 else if(!strcasecmp(afname, "any"))
 329                         addressfamily = AF_UNSPEC;
 330                 else {
 331                         logger(LOG_ERR, "Invalid address family!");
 332                         return false;
 333                 }
 334                 free(afname);
 335         }
 336
 337         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 338
 339         /* Generate packet encryption key */
 340
 341         if(get_config_string
 342            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 343                 if(!strcasecmp(cipher, "none")) {
 344                         myself->incipher = NULL;
 345                 } else {
 346                         myself->incipher = EVP_get_cipherbyname(cipher);
 347
 348                         if(!myself->incipher) {
 349                                 logger(LOG_ERR, "Unrecognized cipher type!");
 350                                 return false;
 351                         }
 352                 }
 353         } else
 354                 myself->incipher = EVP_aes_256_cbc();
 355
 356         if(myself->incipher)
 357                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 358         else
 359                 myself->inkeylength = 1;
 360
 361         myself->connection->outcipher = EVP_aes_256_ofb();
 362
 363         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 364                 keylifetime = 3600;
 365
 366         keyexpires = now + keylifetime;
 367
 368         /* Check if we want to use message authentication codes... */
 369
 370         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 371                 if(!strcasecmp(digest, "none")) {
 372                         myself->indigest = NULL;
 373                 } else {
 374                         myself->indigest = EVP_get_digestbyname(digest);
 375
 376                         if(!myself->indigest) {
 377                                 logger(LOG_ERR, "Unrecognized digest type!");
 378                                 return false;
 379                         }
 380                 }
 381         } else
 382                 myself->indigest = EVP_sha256();
 383
 384         myself->connection->outdigest = EVP_sha256();
 385
 386         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 387                 if(myself->indigest) {
 388                         if(myself->inmaclength > myself->indigest->md_size) {
 389                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 390                                 return false;
 391                         } else if(myself->inmaclength < 0) {
 392                                 logger(LOG_ERR, "Bogus MAC length!");
 393                                 return false;
 394                         }
 395                 }
 396         } else
 397                 myself->inmaclength = 4;
 398
 399         myself->connection->outmaclength = 0;
 400
 401         /* Compression */
 402
 403         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 404                 if(myself->incompression < 0 || myself->incompression > 11) {
 405                         logger(LOG_ERR, "Bogus compression level!");
 406                         return false;
 407                 }
 408         } else
 409                 myself->incompression = 0;
 410
 411         myself->connection->outcompression = 0;
 412
 413         /* Done */
 414
 415         myself->nexthop = myself;
 416         myself->via = myself;
 417         myself->status.reachable = true;
 418         node_add(myself);
 419
 420         graph();
 421
 422         /* Open device */
 423
 424         if(!setup_device())
 425                 return false;
 426
 427         /* Run tinc-up script to further initialize the tap interface */
 428         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 429         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 430         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 431         xasprintf(&envp[3], "NAME=%s", myself->name);
 432         envp[4] = NULL;
 433
 434         execute_script("tinc-up", envp);
 435
 436         for(i = 0; i < 5; i++)
 437                 free(envp[i]);
 438
 439         /* Run subnet-up scripts for our own subnets */
 440
 441         subnet_update(myself, NULL, true);
 442
 443         /* Open sockets */
 444
 445         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 446
 447         hint.ai_family = addressfamily;
 448         hint.ai_socktype = SOCK_STREAM;
 449         hint.ai_protocol = IPPROTO_TCP;
 450         hint.ai_flags = AI_PASSIVE;
 451
 452         err = getaddrinfo(address, myport, &hint, &ai);
 453
 454         if(err || !ai) {
 455                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 456                            gai_strerror(err));
 457                 return false;
 458         }
 459
 460         listen_sockets = 0;
 461
 462         for(aip = ai; aip; aip = aip->ai_next) {
 463                 listen_socket[listen_sockets].tcp =
 464                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 465
 466                 if(listen_socket[listen_sockets].tcp < 0)
 467                         continue;
 468
 469                 listen_socket[listen_sockets].udp =
 470                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 471
 472                 if(listen_socket[listen_sockets].udp < 0)
 473                         continue;
 474
 475                 ifdebug(CONNECTIONS) {
 476                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 477                         logger(LOG_NOTICE, "Listening on %s", hostname);
 478                         free(hostname);
 479                 }
 480
 481                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 482                 listen_sockets++;
 483         }
 484
 485         freeaddrinfo(ai);
 486
 487         if(listen_sockets)
 488                 logger(LOG_NOTICE, "Ready");
 489         else {
 490                 logger(LOG_ERR, "Unable to create any listening socket!");
 491                 return false;
 492         }
 493
 494         return true;
 495 }
 496
 497 /*
 498   initialize network
 499 */
 500 bool setup_network(void) {
 501         now = time(NULL);
 502
 503         init_events();
 504         init_connections();
 505         init_subnets();
 506         init_nodes();
 507         init_edges();
 508         init_requests();
 509
 510         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 511                 if(pinginterval < 1) {
 512                         pinginterval = 86400;
 513                 }
 514         } else
 515                 pinginterval = 60;
 516
 517         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 518                 pingtimeout = 5;
 519         if(pingtimeout < 1 || pingtimeout > pinginterval)
 520                 pingtimeout = pinginterval;
 521
 522         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 523                 maxoutbufsize = 10 * MTU;
 524
 525         if(!setup_myself())
 526                 return false;
 527
 528         return true;
 529 }
 530
 531 /*
 532   close all open network connections
 533 */
 534 void close_network_connections(void) {
 535         avl_node_t *node, *next;
 536         connection_t *c;
 537         char *envp[5];
 538         int i;
 539
 540         for(node = connection_tree->head; node; node = next) {
 541                 next = node->next;
 542                 c = node->data;
 543                 c->outgoing = false;
 544                 terminate_connection(c, false);
 545         }
 546
 547         list_delete_list(outgoing_list);
 548
 549         if(myself && myself->connection) {
 550                 subnet_update(myself, NULL, false);
 551                 terminate_connection(myself->connection, false);
 552                 free_connection(myself->connection);
 553         }
 554
 555         for(i = 0; i < listen_sockets; i++) {
 556                 close(listen_socket[i].tcp);
 557                 close(listen_socket[i].udp);
 558         }
 559
 560         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 561         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 562         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 563         xasprintf(&envp[3], "NAME=%s", myself->name);
 564         envp[4] = NULL;
 565
 566         exit_requests();
 567         exit_edges();
 568         exit_subnets();
 569         exit_nodes();
 570         exit_connections();
 571         exit_events();
 572
 573         execute_script("tinc-down", envp);
 574
 575         if(myport) free(myport);
 576
 577         for(i = 0; i < 4; i++)
 578                 free(envp[i]);
 579
 580         close_device();
 581
 582         return;
 583 }