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                   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   Configure node_t myself and set up the local sockets (listen only)
 206 */
 207 bool setup_myself(void) {
 208         config_t *cfg;
 209         subnet_t *subnet;
 210         char *name, *hostname, *mode, *afname, *cipher, *digest;
 211         char *address = NULL;
 212         char *envp[5];
 213         struct addrinfo *ai, *aip, hint = {0};
 214         bool choice;
 215         int i, err;
 216
 217         myself = new_node();
 218         myself->connection = new_connection();
 219         init_configuration(&myself->connection->config_tree);
 220
 221         myself->hostname = xstrdup("MYSELF");
 222         myself->connection->hostname = xstrdup("MYSELF");
 223
 224         myself->connection->options = 0;
 225         myself->connection->protocol_version = PROT_CURRENT;
 226
 227         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 228                 logger(LOG_ERR, "Name for tinc daemon required!");
 229                 return false;
 230         }
 231
 232         if(!check_id(name)) {
 233                 logger(LOG_ERR, "Invalid name for myself!");
 234                 free(name);
 235                 return false;
 236         }
 237
 238         myself->name = name;
 239         myself->connection->name = xstrdup(name);
 240
 241         if(!read_connection_config(myself->connection)) {
 242                 logger(LOG_ERR, "Cannot open host configuration file for myself!");
 243                 return false;
 244         }
 245
 246         if(!read_rsa_private_key())
 247                 return false;
 248
 249         if(!get_config_string(lookup_config(config_tree, "Port"), &myport)
 250                         && !get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 251                 myport = xstrdup("655");
 252
 253         /* Read in all the subnets specified in the host configuration file */
 254
 255         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 256
 257         while(cfg) {
 258                 if(!get_config_subnet(cfg, &subnet))
 259                         return false;
 260
 261                 subnet_add(myself, subnet);
 262
 263                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 264         }
 265
 266         /* Check some options */
 267
 268         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 269                 myself->options |= OPTION_INDIRECT;
 270
 271         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 272                 myself->options |= OPTION_TCPONLY;
 273
 274         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 275                 myself->options |= OPTION_INDIRECT;
 276
 277         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 278                 myself->options |= OPTION_TCPONLY;
 279
 280         if(myself->options & OPTION_TCPONLY)
 281                 myself->options |= OPTION_INDIRECT;
 282
 283         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 284
 285         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 286                 if(!strcasecmp(mode, "router"))
 287                         routing_mode = RMODE_ROUTER;
 288                 else if(!strcasecmp(mode, "switch"))
 289                         routing_mode = RMODE_SWITCH;
 290                 else if(!strcasecmp(mode, "hub"))
 291                         routing_mode = RMODE_HUB;
 292                 else {
 293                         logger(LOG_ERR, "Invalid routing mode!");
 294                         return false;
 295                 }
 296                 free(mode);
 297         } else
 298                 routing_mode = RMODE_ROUTER;
 299
 300         choice = true;
 301         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 302         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 303         if(choice)
 304                 myself->options |= OPTION_PMTU_DISCOVERY;
 305
 306         choice = true;
 307         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 308         get_config_bool(lookup_config(myself->connection->config_tree, "ClampMSS"), &choice);
 309         if(choice)
 310                 myself->options |= OPTION_CLAMP_MSS;
 311
 312         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 313
 314 #if !defined(SOL_IP) || !defined(IP_TOS)
 315         if(priorityinheritance)
 316                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 317 #endif
 318
 319         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 320                 macexpire = 600;
 321
 322         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 323                 if(maxtimeout <= 0) {
 324                         logger(LOG_ERR, "Bogus maximum timeout!");
 325                         return false;
 326                 }
 327         } else
 328                 maxtimeout = 900;
 329
 330         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 331                 if(!strcasecmp(afname, "IPv4"))
 332                         addressfamily = AF_INET;
 333                 else if(!strcasecmp(afname, "IPv6"))
 334                         addressfamily = AF_INET6;
 335                 else if(!strcasecmp(afname, "any"))
 336                         addressfamily = AF_UNSPEC;
 337                 else {
 338                         logger(LOG_ERR, "Invalid address family!");
 339                         return false;
 340                 }
 341                 free(afname);
 342         }
 343
 344         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 345
 346         /* Generate packet encryption key */
 347
 348         if(get_config_string
 349            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 350                 if(!strcasecmp(cipher, "none")) {
 351                         myself->incipher = NULL;
 352                 } else {
 353                         myself->incipher = EVP_get_cipherbyname(cipher);
 354
 355                         if(!myself->incipher) {
 356                                 logger(LOG_ERR, "Unrecognized cipher type!");
 357                                 return false;
 358                         }
 359                 }
 360         } else
 361                 myself->incipher = EVP_bf_cbc();
 362
 363         if(myself->incipher)
 364                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 365         else
 366                 myself->inkeylength = 1;
 367
 368         myself->connection->outcipher = EVP_bf_ofb();
 369
 370         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 371                 keylifetime = 3600;
 372
 373         keyexpires = now + keylifetime;
 374
 375         /* Check if we want to use message authentication codes... */
 376
 377         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 378                 if(!strcasecmp(digest, "none")) {
 379                         myself->indigest = NULL;
 380                 } else {
 381                         myself->indigest = EVP_get_digestbyname(digest);
 382
 383                         if(!myself->indigest) {
 384                                 logger(LOG_ERR, "Unrecognized digest type!");
 385                                 return false;
 386                         }
 387                 }
 388         } else
 389                 myself->indigest = EVP_sha1();
 390
 391         myself->connection->outdigest = EVP_sha1();
 392
 393         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 394                 if(myself->indigest) {
 395                         if(myself->inmaclength > myself->indigest->md_size) {
 396                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 397                                 return false;
 398                         } else if(myself->inmaclength < 0) {
 399                                 logger(LOG_ERR, "Bogus MAC length!");
 400                                 return false;
 401                         }
 402                 }
 403         } else
 404                 myself->inmaclength = 4;
 405
 406         myself->connection->outmaclength = 0;
 407
 408         /* Compression */
 409
 410         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 411                 if(myself->incompression < 0 || myself->incompression > 11) {
 412                         logger(LOG_ERR, "Bogus compression level!");
 413                         return false;
 414                 }
 415         } else
 416                 myself->incompression = 0;
 417
 418         myself->connection->outcompression = 0;
 419
 420         /* Done */
 421
 422         myself->nexthop = myself;
 423         myself->via = myself;
 424         myself->status.reachable = true;
 425         node_add(myself);
 426
 427         graph();
 428
 429         /* Open device */
 430
 431         if(!setup_device())
 432                 return false;
 433
 434         /* Run tinc-up script to further initialize the tap interface */
 435         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 436         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 437         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 438         xasprintf(&envp[3], "NAME=%s", myself->name);
 439         envp[4] = NULL;
 440
 441         execute_script("tinc-up", envp);
 442
 443         for(i = 0; i < 5; i++)
 444                 free(envp[i]);
 445
 446         /* Run subnet-up scripts for our own subnets */
 447
 448         subnet_update(myself, NULL, true);
 449
 450         /* Open sockets */
 451
 452         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 453
 454         hint.ai_family = addressfamily;
 455         hint.ai_socktype = SOCK_STREAM;
 456         hint.ai_protocol = IPPROTO_TCP;
 457         hint.ai_flags = AI_PASSIVE;
 458
 459         err = getaddrinfo(address, myport, &hint, &ai);
 460
 461         if(err || !ai) {
 462                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 463                            gai_strerror(err));
 464                 return false;
 465         }
 466
 467         listen_sockets = 0;
 468
 469         for(aip = ai; aip; aip = aip->ai_next) {
 470                 listen_socket[listen_sockets].tcp =
 471                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 472
 473                 if(listen_socket[listen_sockets].tcp < 0)
 474                         continue;
 475
 476                 listen_socket[listen_sockets].udp =
 477                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 478
 479                 if(listen_socket[listen_sockets].udp < 0)
 480                         continue;
 481
 482                 ifdebug(CONNECTIONS) {
 483                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 484                         logger(LOG_NOTICE, "Listening on %s", hostname);
 485                         free(hostname);
 486                 }
 487
 488                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 489                 listen_sockets++;
 490         }
 491
 492         freeaddrinfo(ai);
 493
 494         if(listen_sockets)
 495                 logger(LOG_NOTICE, "Ready");
 496         else {
 497                 logger(LOG_ERR, "Unable to create any listening socket!");
 498                 return false;
 499         }
 500
 501         return true;
 502 }
 503
 504 /*
 505   initialize network
 506 */
 507 bool setup_network(void) {
 508         now = time(NULL);
 509
 510         init_events();
 511         init_connections();
 512         init_subnets();
 513         init_nodes();
 514         init_edges();
 515         init_requests();
 516
 517         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 518                 if(pinginterval < 1) {
 519                         pinginterval = 86400;
 520                 }
 521         } else
 522                 pinginterval = 60;
 523
 524         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 525                 pingtimeout = 5;
 526         if(pingtimeout < 1 || pingtimeout > pinginterval)
 527                 pingtimeout = pinginterval;
 528
 529         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 530                 maxoutbufsize = 10 * MTU;
 531
 532         if(!setup_myself())
 533                 return false;
 534
 535         return true;
 536 }
 537
 538 /*
 539   close all open network connections
 540 */
 541 void close_network_connections(void) {
 542         avl_node_t *node, *next;
 543         connection_t *c;
 544         char *envp[5];
 545         int i;
 546
 547         for(node = connection_tree->head; node; node = next) {
 548                 next = node->next;
 549                 c = node->data;
 550                 c->outgoing = NULL;
 551                 terminate_connection(c, false);
 552         }
 553
 554         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
 555                 outgoing_t *outgoing = node->data;
 556
 557                 if(outgoing->event)
 558                         event_del(outgoing->event);
 559         }
 560
 561         list_delete_list(outgoing_list);
 562
 563         if(myself && myself->connection) {
 564                 subnet_update(myself, NULL, false);
 565                 terminate_connection(myself->connection, false);
 566                 free_connection(myself->connection);
 567         }
 568
 569         for(i = 0; i < listen_sockets; i++) {
 570                 close(listen_socket[i].tcp);
 571                 close(listen_socket[i].udp);
 572         }
 573
 574         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 575         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 576         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 577         xasprintf(&envp[3], "NAME=%s", myself->name);
 578         envp[4] = NULL;
 579
 580         exit_requests();
 581         exit_edges();
 582         exit_subnets();
 583         exit_nodes();
 584         exit_connections();
 585         exit_events();
 586
 587         execute_script("tinc-down", envp);
 588
 589         if(myport) free(myport);
 590
 591         for(i = 0; i < 4; i++)
 592                 free(envp[i]);
 593
 594         close_device();
 595
 596         return;
 597 }