www.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 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, *s2;
 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                 #ifdef _DIRENT_HAVE_D_TYPE
 232                 //if(ent->d_type != DT_REG)
 233                 //      continue;
 234                 #endif
 235
 236                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 237                 init_configuration(&config_tree);
 238                 result = read_config_file(config_tree, fname);
 239                 free(fname);
 240                 if(!result)
 241                         continue;
 242
 243                 if(!n) {
 244                         n = new_node();
 245                         n->name = xstrdup(ent->d_name);
 246                         node_add(n);
 247                 }
 248
 249                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
 250                         if(!get_config_subnet(cfg, &s))
 251                                 continue;
 252
 253                         if((s2 = lookup_subnet(n, s))) {
 254                                 s2->expires = -1;
 255                         } else {
 256                                 subnet_add(n, s);
 257                         }
 258                 }
 259
 260                 exit_configuration(&config_tree);
 261         }
 262
 263         closedir(dir);
 264 }
 265
 266 /*
 267   Configure node_t myself and set up the local sockets (listen only)
 268 */
 269 bool setup_myself(void) {
 270         config_t *cfg;
 271         subnet_t *subnet;
 272         char *name, *hostname, *mode, *afname, *cipher, *digest;
 273         char *address = NULL;
 274         char *envp[5];
 275         struct addrinfo *ai, *aip, hint = {0};
 276         bool choice;
 277         int i, err;
 278
 279         myself = new_node();
 280         myself->connection = new_connection();
 281         init_configuration(&myself->connection->config_tree);
 282
 283         myself->hostname = xstrdup("MYSELF");
 284         myself->connection->hostname = xstrdup("MYSELF");
 285
 286         myself->connection->options = 0;
 287         myself->connection->protocol_version = PROT_CURRENT;
 288
 289         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 290                 logger(LOG_ERR, "Name for tinc daemon required!");
 291                 return false;
 292         }
 293
 294         if(!check_id(name)) {
 295                 logger(LOG_ERR, "Invalid name for myself!");
 296                 free(name);
 297                 return false;
 298         }
 299
 300         myself->name = name;
 301         myself->connection->name = xstrdup(name);
 302
 303         if(!read_connection_config(myself->connection)) {
 304                 logger(LOG_ERR, "Cannot open host configuration file for myself!");
 305                 return false;
 306         }
 307
 308         if(!read_rsa_private_key())
 309                 return false;
 310
 311         if(!get_config_string(lookup_config(config_tree, "Port"), &myport)
 312                         && !get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 313                 myport = xstrdup("655");
 314
 315         if(!atoi(myport)) {
 316                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 317                 sockaddr_t sa;
 318                 if(!ai || !ai->ai_addr)
 319                         return false;
 320                 free(myport);
 321                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 322                 sockaddr2str(&sa, NULL, &myport);
 323         }
 324
 325         /* Read in all the subnets specified in the host configuration file */
 326
 327         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 328
 329         while(cfg) {
 330                 if(!get_config_subnet(cfg, &subnet))
 331                         return false;
 332
 333                 subnet_add(myself, subnet);
 334
 335                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 336         }
 337
 338         /* Check some options */
 339
 340         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 341                 myself->options |= OPTION_INDIRECT;
 342
 343         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 344                 myself->options |= OPTION_TCPONLY;
 345
 346         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 347                 myself->options |= OPTION_INDIRECT;
 348
 349         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 350                 myself->options |= OPTION_TCPONLY;
 351
 352         if(myself->options & OPTION_TCPONLY)
 353                 myself->options |= OPTION_INDIRECT;
 354
 355         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 356         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 357         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 358         strictsubnets |= tunnelserver;
 359
 360         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 361                 if(!strcasecmp(mode, "router"))
 362                         routing_mode = RMODE_ROUTER;
 363                 else if(!strcasecmp(mode, "switch"))
 364                         routing_mode = RMODE_SWITCH;
 365                 else if(!strcasecmp(mode, "hub"))
 366                         routing_mode = RMODE_HUB;
 367                 else {
 368                         logger(LOG_ERR, "Invalid routing mode!");
 369                         return false;
 370                 }
 371                 free(mode);
 372         }
 373
 374         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 375                 if(!strcasecmp(mode, "off"))
 376                         forwarding_mode = FMODE_OFF;
 377                 else if(!strcasecmp(mode, "internal"))
 378                         forwarding_mode = FMODE_INTERNAL;
 379                 else if(!strcasecmp(mode, "kernel"))
 380                         forwarding_mode = FMODE_KERNEL;
 381                 else {
 382                         logger(LOG_ERR, "Invalid forwarding mode!");
 383                         return false;
 384                 }
 385                 free(mode);
 386         }
 387
 388         choice = true;
 389         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 390         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 391         if(choice)
 392                 myself->options |= OPTION_PMTU_DISCOVERY;
 393
 394         choice = true;
 395         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 396         get_config_bool(lookup_config(myself->connection->config_tree, "ClampMSS"), &choice);
 397         if(choice)
 398                 myself->options |= OPTION_CLAMP_MSS;
 399
 400         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 401
 402 #if !defined(SOL_IP) || !defined(IP_TOS)
 403         if(priorityinheritance)
 404                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 405 #endif
 406
 407         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 408                 macexpire = 600;
 409
 410         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 411                 if(maxtimeout <= 0) {
 412                         logger(LOG_ERR, "Bogus maximum timeout!");
 413                         return false;
 414                 }
 415         } else
 416                 maxtimeout = 900;
 417
 418         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 419                 if(!strcasecmp(afname, "IPv4"))
 420                         addressfamily = AF_INET;
 421                 else if(!strcasecmp(afname, "IPv6"))
 422                         addressfamily = AF_INET6;
 423                 else if(!strcasecmp(afname, "any"))
 424                         addressfamily = AF_UNSPEC;
 425                 else {
 426                         logger(LOG_ERR, "Invalid address family!");
 427                         return false;
 428                 }
 429                 free(afname);
 430         }
 431
 432         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 433
 434         /* Generate packet encryption key */
 435
 436         if(get_config_string
 437            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 438                 if(!strcasecmp(cipher, "none")) {
 439                         myself->incipher = NULL;
 440                 } else {
 441                         myself->incipher = EVP_get_cipherbyname(cipher);
 442
 443                         if(!myself->incipher) {
 444                                 logger(LOG_ERR, "Unrecognized cipher type!");
 445                                 return false;
 446                         }
 447                 }
 448         } else
 449                 myself->incipher = EVP_bf_cbc();
 450
 451         if(myself->incipher)
 452                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 453         else
 454                 myself->inkeylength = 1;
 455
 456         myself->connection->outcipher = EVP_bf_ofb();
 457
 458         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 459                 keylifetime = 3600;
 460
 461         keyexpires = now + keylifetime;
 462
 463         /* Check if we want to use message authentication codes... */
 464
 465         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 466                 if(!strcasecmp(digest, "none")) {
 467                         myself->indigest = NULL;
 468                 } else {
 469                         myself->indigest = EVP_get_digestbyname(digest);
 470
 471                         if(!myself->indigest) {
 472                                 logger(LOG_ERR, "Unrecognized digest type!");
 473                                 return false;
 474                         }
 475                 }
 476         } else
 477                 myself->indigest = EVP_sha1();
 478
 479         myself->connection->outdigest = EVP_sha1();
 480
 481         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
 482                 if(myself->indigest) {
 483                         if(myself->inmaclength > myself->indigest->md_size) {
 484                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 485                                 return false;
 486                         } else if(myself->inmaclength < 0) {
 487                                 logger(LOG_ERR, "Bogus MAC length!");
 488                                 return false;
 489                         }
 490                 }
 491         } else
 492                 myself->inmaclength = 4;
 493
 494         myself->connection->outmaclength = 0;
 495
 496         /* Compression */
 497
 498         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 499                 if(myself->incompression < 0 || myself->incompression > 11) {
 500                         logger(LOG_ERR, "Bogus compression level!");
 501                         return false;
 502                 }
 503         } else
 504                 myself->incompression = 0;
 505
 506         myself->connection->outcompression = 0;
 507
 508         /* Done */
 509
 510         myself->nexthop = myself;
 511         myself->via = myself;
 512         myself->status.reachable = true;
 513         node_add(myself);
 514
 515         graph();
 516
 517         if(strictsubnets)
 518                 load_all_subnets();
 519
 520         /* Open device */
 521
 522         if(!setup_device())
 523                 return false;
 524
 525         /* Run tinc-up script to further initialize the tap interface */
 526         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 527         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 528         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 529         xasprintf(&envp[3], "NAME=%s", myself->name);
 530         envp[4] = NULL;
 531
 532         execute_script("tinc-up", envp);
 533
 534         for(i = 0; i < 5; i++)
 535                 free(envp[i]);
 536
 537         /* Run subnet-up scripts for our own subnets */
 538
 539         subnet_update(myself, NULL, true);
 540
 541         /* Open sockets */
 542
 543         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 544
 545         hint.ai_family = addressfamily;
 546         hint.ai_socktype = SOCK_STREAM;
 547         hint.ai_protocol = IPPROTO_TCP;
 548         hint.ai_flags = AI_PASSIVE;
 549
 550         err = getaddrinfo(address, myport, &hint, &ai);
 551
 552         if(err || !ai) {
 553                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 554                            gai_strerror(err));
 555                 return false;
 556         }
 557
 558         listen_sockets = 0;
 559
 560         for(aip = ai; aip; aip = aip->ai_next) {
 561                 listen_socket[listen_sockets].tcp =
 562                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 563
 564                 if(listen_socket[listen_sockets].tcp < 0)
 565                         continue;
 566
 567                 listen_socket[listen_sockets].udp =
 568                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 569
 570                 if(listen_socket[listen_sockets].udp < 0)
 571                         continue;
 572
 573                 ifdebug(CONNECTIONS) {
 574                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 575                         logger(LOG_NOTICE, "Listening on %s", hostname);
 576                         free(hostname);
 577                 }
 578
 579                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 580                 listen_sockets++;
 581         }
 582
 583         freeaddrinfo(ai);
 584
 585         if(listen_sockets)
 586                 logger(LOG_NOTICE, "Ready");
 587         else {
 588                 logger(LOG_ERR, "Unable to create any listening socket!");
 589                 return false;
 590         }
 591
 592         return true;
 593 }
 594
 595 /*
 596   initialize network
 597 */
 598 bool setup_network(void) {
 599         now = time(NULL);
 600
 601         init_events();
 602         init_connections();
 603         init_subnets();
 604         init_nodes();
 605         init_edges();
 606         init_requests();
 607
 608         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 609                 if(pinginterval < 1) {
 610                         pinginterval = 86400;
 611                 }
 612         } else
 613                 pinginterval = 60;
 614
 615         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 616                 pingtimeout = 5;
 617         if(pingtimeout < 1 || pingtimeout > pinginterval)
 618                 pingtimeout = pinginterval;
 619
 620         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 621                 maxoutbufsize = 10 * MTU;
 622
 623         if(!setup_myself())
 624                 return false;
 625
 626         return true;
 627 }
 628
 629 /*
 630   close all open network connections
 631 */
 632 void close_network_connections(void) {
 633         avl_node_t *node, *next;
 634         connection_t *c;
 635         char *envp[5];
 636         int i;
 637
 638         for(node = connection_tree->head; node; node = next) {
 639                 next = node->next;
 640                 c = node->data;
 641                 c->outgoing = NULL;
 642                 terminate_connection(c, false);
 643         }
 644
 645         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
 646                 outgoing_t *outgoing = node->data;
 647
 648                 if(outgoing->event)
 649                         event_del(outgoing->event);
 650         }
 651
 652         list_delete_list(outgoing_list);
 653
 654         if(myself && myself->connection) {
 655                 subnet_update(myself, NULL, false);
 656                 terminate_connection(myself->connection, false);
 657                 free_connection(myself->connection);
 658         }
 659
 660         for(i = 0; i < listen_sockets; i++) {
 661                 close(listen_socket[i].tcp);
 662                 close(listen_socket[i].udp);
 663         }
 664
 665         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 666         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 667         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 668         xasprintf(&envp[3], "NAME=%s", myself->name);
 669         envp[4] = NULL;
 670
 671         exit_requests();
 672         exit_edges();
 673         exit_subnets();
 674         exit_nodes();
 675         exit_connections();
 676         exit_events();
 677
 678         execute_script("tinc-down", envp);
 679
 680         if(myport) free(myport);
 681
 682         for(i = 0; i < 4; i++)
 683                 free(envp[i]);
 684
 685         close_device();
 686
 687         return;
 688 }