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                   2010      Brandon Black <blblack@gmail.com>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License along
  19     with this program; if not, write to the Free Software Foundation, Inc.,
  20     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21 */
  22
  23 #include "system.h"
  24
  25 #include "splay_tree.h"
  26 #include "cipher.h"
  27 #include "conf.h"
  28 #include "connection.h"
  29 #include "control.h"
  30 #include "device.h"
  31 #include "digest.h"
  32 #include "graph.h"
  33 #include "logger.h"
  34 #include "net.h"
  35 #include "netutl.h"
  36 #include "process.h"
  37 #include "protocol.h"
  38 #include "route.h"
  39 #include "rsa.h"
  40 #include "subnet.h"
  41 #include "utils.h"
  42 #include "xalloc.h"
  43
  44 char *myport;
  45 static struct event device_ev;
  46
  47 bool read_rsa_public_key(connection_t *c) {
  48         FILE *fp;
  49         char *fname;
  50         char *n;
  51         bool result;
  52
  53         /* First, check for simple PublicKey statement */
  54
  55         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &n)) {
  56                 result = rsa_set_hex_public_key(&c->rsa, n, "FFFF");
  57                 free(n);
  58                 return result;
  59         }
  60
  61         /* Else, check for PublicKeyFile statement and read it */
  62
  63         if(!get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
  64                 xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
  65
  66         fp = fopen(fname, "r");
  67
  68         if(!fp) {
  69                 logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  70                            fname, strerror(errno));
  71                 free(fname);
  72                 return false;
  73         }
  74
  75         result = rsa_read_pem_public_key(&c->rsa, fp);
  76         fclose(fp);
  77
  78         if(!result)
  79                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s", fname, strerror(errno));
  80         free(fname);
  81         return result;
  82 }
  83
  84 bool read_rsa_private_key() {
  85         FILE *fp;
  86         char *fname;
  87         char *n, *d;
  88         bool result;
  89
  90         /* First, check for simple PrivateKey statement */
  91
  92         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &d)) {
  93                 if(!get_config_string(lookup_config(config_tree, "PublicKey"), &n)) {
  94                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
  95                         free(d);
  96                         return false;
  97                 }
  98                 result = rsa_set_hex_private_key(&myself->connection->rsa, n, "FFFF", d);
  99                 free(n);
 100                 free(d);
 101                 return true;
 102         }
 103
 104         /* Else, check for PrivateKeyFile statement and read it */
 105
 106         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 107                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 108
 109         fp = fopen(fname, "r");
 110
 111         if(!fp) {
 112                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 113                            fname, strerror(errno));
 114                 free(fname);
 115                 return false;
 116         }
 117
 118 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 119         struct stat s;
 120
 121         if(fstat(fileno(fp), &s)) {
 122                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'", fname, strerror(errno));
 123                 free(fname);
 124                 return false;
 125         }
 126
 127         if(s.st_mode & ~0100700)
 128                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 129 #endif
 130
 131         result = rsa_read_pem_private_key(&myself->connection->rsa, fp);
 132         fclose(fp);
 133
 134         if(!result)
 135                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s", fname, strerror(errno));
 136         free(fname);
 137         return result;
 138 }
 139
 140 static struct event keyexpire_event;
 141
 142 static void keyexpire_handler(int fd, short events, void *data) {
 143         regenerate_key();
 144 }
 145
 146 void regenerate_key() {
 147         if(timeout_initialized(&keyexpire_event)) {
 148                 ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys");
 149                 event_del(&keyexpire_event);
 150                 send_key_changed(broadcast, myself);
 151         } else {
 152                 timeout_set(&keyexpire_event, keyexpire_handler, NULL);
 153         }
 154
 155         event_add(&keyexpire_event, &(struct timeval){keylifetime, 0});
 156 }
 157
 158 /*
 159   Read Subnets from all host config files
 160 */
 161 void load_all_subnets(void) {
 162         DIR *dir;
 163         struct dirent *ent;
 164         char *dname;
 165         char *fname;
 166         splay_tree_t *config_tree;
 167         config_t *cfg;
 168         subnet_t *s, *s2;
 169         node_t *n;
 170         bool result;
 171
 172         xasprintf(&dname, "%s/hosts", confbase);
 173         dir = opendir(dname);
 174         if(!dir) {
 175                 logger(LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 176                 free(dname);
 177                 return;
 178         }
 179
 180         while((ent = readdir(dir))) {
 181                 if(!check_id(ent->d_name))
 182                         continue;
 183
 184                 n = lookup_node(ent->d_name);
 185                 #ifdef _DIRENT_HAVE_D_TYPE
 186                 //if(ent->d_type != DT_REG)
 187                 //      continue;
 188                 #endif
 189
 190                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 191                 init_configuration(&config_tree);
 192                 result = read_config_file(config_tree, fname);
 193                 free(fname);
 194                 if(!result)
 195                         continue;
 196
 197                 if(!n) {
 198                         n = new_node();
 199                         n->name = xstrdup(ent->d_name);
 200                         node_add(n);
 201                 }
 202
 203                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
 204                         if(!get_config_subnet(cfg, &s))
 205                                 continue;
 206
 207                         if((s2 = lookup_subnet(n, s))) {
 208                                 s2->expires = -1;
 209                         } else {
 210                                 subnet_add(n, s);
 211                         }
 212                 }
 213
 214                 exit_configuration(&config_tree);
 215         }
 216
 217         closedir(dir);
 218 }
 219
 220 /*
 221   Configure node_t myself and set up the local sockets (listen only)
 222 */
 223 bool setup_myself(void) {
 224         config_t *cfg;
 225         subnet_t *subnet;
 226         char *name, *hostname, *mode, *afname, *cipher, *digest;
 227         char *fname = NULL;
 228         char *address = NULL;
 229         char *envp[5];
 230         struct addrinfo *ai, *aip, hint = {0};
 231         bool choice;
 232         int i, err;
 233         int replaywin_int;
 234
 235         myself = new_node();
 236         myself->connection = new_connection();
 237
 238         myself->hostname = xstrdup("MYSELF");
 239         myself->connection->hostname = xstrdup("MYSELF");
 240
 241         myself->connection->options = 0;
 242         myself->connection->protocol_version = PROT_CURRENT;
 243
 244         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 245                 logger(LOG_ERR, "Name for tinc daemon required!");
 246                 return false;
 247         }
 248
 249         if(!check_id(name)) {
 250                 logger(LOG_ERR, "Invalid name for myself!");
 251                 free(name);
 252                 return false;
 253         }
 254
 255         myself->name = name;
 256         myself->connection->name = xstrdup(name);
 257         xasprintf(&fname, "%s/hosts/%s", confbase, name);
 258         read_config_options(config_tree, name);
 259         read_config_file(config_tree, fname);
 260         free(fname);
 261
 262         if(!read_rsa_private_key())
 263                 return false;
 264
 265         if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
 266                 myport = xstrdup("655");
 267
 268         if(!atoi(myport)) {
 269                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 270                 sockaddr_t sa;
 271                 if(!ai || !ai->ai_addr)
 272                         return false;
 273                 free(myport);
 274                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 275                 sockaddr2str(&sa, NULL, &myport);
 276         }
 277
 278         /* Read in all the subnets specified in the host configuration file */
 279
 280         cfg = lookup_config(config_tree, "Subnet");
 281
 282         while(cfg) {
 283                 if(!get_config_subnet(cfg, &subnet))
 284                         return false;
 285
 286                 subnet_add(myself, subnet);
 287
 288                 cfg = lookup_config_next(config_tree, cfg);
 289         }
 290
 291         /* Check some options */
 292
 293         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 294                 myself->options |= OPTION_INDIRECT;
 295
 296         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 297                 myself->options |= OPTION_TCPONLY;
 298
 299         if(myself->options & OPTION_TCPONLY)
 300                 myself->options |= OPTION_INDIRECT;
 301
 302         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 303         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 304         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 305         strictsubnets |= tunnelserver;
 306
 307         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 308                 if(!strcasecmp(mode, "router"))
 309                         routing_mode = RMODE_ROUTER;
 310                 else if(!strcasecmp(mode, "switch"))
 311                         routing_mode = RMODE_SWITCH;
 312                 else if(!strcasecmp(mode, "hub"))
 313                         routing_mode = RMODE_HUB;
 314                 else {
 315                         logger(LOG_ERR, "Invalid routing mode!");
 316                         return false;
 317                 }
 318                 free(mode);
 319         }
 320
 321         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 322                 if(!strcasecmp(mode, "off"))
 323                         forwarding_mode = FMODE_OFF;
 324                 else if(!strcasecmp(mode, "internal"))
 325                         forwarding_mode = FMODE_INTERNAL;
 326                 else if(!strcasecmp(mode, "kernel"))
 327                         forwarding_mode = FMODE_KERNEL;
 328                 else {
 329                         logger(LOG_ERR, "Invalid forwarding mode!");
 330                         return false;
 331                 }
 332                 free(mode);
 333         }
 334
 335         choice = true;
 336         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 337         if(choice)
 338                 myself->options |= OPTION_PMTU_DISCOVERY;
 339
 340         choice = true;
 341         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 342         if(choice)
 343                 myself->options |= OPTION_CLAMP_MSS;
 344
 345         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 346
 347 #if !defined(SOL_IP) || !defined(IP_TOS)
 348         if(priorityinheritance)
 349                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 350 #endif
 351
 352         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 353                 macexpire = 600;
 354
 355         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 356                 if(maxtimeout <= 0) {
 357                         logger(LOG_ERR, "Bogus maximum timeout!");
 358                         return false;
 359                 }
 360         } else
 361                 maxtimeout = 900;
 362
 363         if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 364                 if(udp_rcvbuf <= 0) {
 365                         logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
 366                         return false;
 367                 }
 368         }
 369
 370         if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
 371                 if(udp_sndbuf <= 0) {
 372                         logger(LOG_ERR, "UDPSndBuf cannot be negative!");
 373                         return false;
 374                 }
 375         }
 376
 377         if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
 378                 if(replaywin_int < 0) {
 379                         logger(LOG_ERR, "ReplayWindow cannot be negative!");
 380                         return false;
 381                 }
 382                 replaywin = (unsigned)replaywin_int;
 383         }
 384
 385         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 386                 if(!strcasecmp(afname, "IPv4"))
 387                         addressfamily = AF_INET;
 388                 else if(!strcasecmp(afname, "IPv6"))
 389                         addressfamily = AF_INET6;
 390                 else if(!strcasecmp(afname, "any"))
 391                         addressfamily = AF_UNSPEC;
 392                 else {
 393                         logger(LOG_ERR, "Invalid address family!");
 394                         return false;
 395                 }
 396                 free(afname);
 397         }
 398
 399         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 400
 401         /* Generate packet encryption key */
 402
 403         if(!get_config_string(lookup_config(config_tree, "Cipher"), &cipher))
 404                 cipher = xstrdup("blowfish");
 405
 406         if(!cipher_open_by_name(&myself->incipher, cipher)) {
 407                 logger(LOG_ERR, "Unrecognized cipher type!");
 408                 return false;
 409         }
 410
 411         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 412                 keylifetime = 3600;
 413
 414         regenerate_key();
 415
 416         /* Check if we want to use message authentication codes... */
 417
 418         if(!get_config_string(lookup_config(config_tree, "Digest"), &digest))
 419                 digest = xstrdup("sha1");
 420
 421         int maclength = 4;
 422         get_config_int(lookup_config(config_tree, "MACLength"), &maclength);
 423
 424         if(maclength < 0) {
 425                 logger(LOG_ERR, "Bogus MAC length!");
 426                 return false;
 427         }
 428
 429         if(!digest_open_by_name(&myself->indigest, digest, maclength)) {
 430                 logger(LOG_ERR, "Unrecognized digest type!");
 431                 return false;
 432         }
 433
 434         /* Compression */
 435
 436         if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
 437                 if(myself->incompression < 0 || myself->incompression > 11) {
 438                         logger(LOG_ERR, "Bogus compression level!");
 439                         return false;
 440                 }
 441         } else
 442                 myself->incompression = 0;
 443
 444         myself->connection->outcompression = 0;
 445
 446         /* Done */
 447
 448         myself->nexthop = myself;
 449         myself->via = myself;
 450         myself->status.reachable = true;
 451         node_add(myself);
 452
 453         graph();
 454
 455         if(strictsubnets)
 456                 load_all_subnets();
 457
 458         /* Open device */
 459
 460         if(!setup_device())
 461                 return false;
 462
 463         if(device_fd >= 0) {
 464                 event_set(&device_ev, device_fd, EV_READ|EV_PERSIST, handle_device_data, NULL);
 465
 466                 if (event_add(&device_ev, NULL) < 0) {
 467                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 468                         close_device();
 469                         return false;
 470                 }
 471         }
 472
 473         /* Run tinc-up script to further initialize the tap interface */
 474         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 475         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 476         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 477         xasprintf(&envp[3], "NAME=%s", myself->name);
 478         envp[4] = NULL;
 479
 480         execute_script("tinc-up", envp);
 481
 482         for(i = 0; i < 4; i++)
 483                 free(envp[i]);
 484
 485         /* Run subnet-up scripts for our own subnets */
 486
 487         subnet_update(myself, NULL, true);
 488
 489         /* Open sockets */
 490
 491         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 492
 493         hint.ai_family = addressfamily;
 494         hint.ai_socktype = SOCK_STREAM;
 495         hint.ai_protocol = IPPROTO_TCP;
 496         hint.ai_flags = AI_PASSIVE;
 497
 498         err = getaddrinfo(address, myport, &hint, &ai);
 499
 500         if(err || !ai) {
 501                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 502                            gai_strerror(err));
 503                 return false;
 504         }
 505
 506         listen_sockets = 0;
 507
 508         for(aip = ai; aip; aip = aip->ai_next) {
 509                 listen_socket[listen_sockets].tcp =
 510                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 511
 512                 if(listen_socket[listen_sockets].tcp < 0)
 513                         continue;
 514
 515                 listen_socket[listen_sockets].udp =
 516                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 517
 518                 if(listen_socket[listen_sockets].udp < 0) {
 519                         close(listen_socket[listen_sockets].tcp);
 520                         continue;
 521                 }
 522
 523                 event_set(&listen_socket[listen_sockets].ev_tcp,
 524                                   listen_socket[listen_sockets].tcp,
 525                                   EV_READ|EV_PERSIST,
 526                                   handle_new_meta_connection, NULL);
 527                 if(event_add(&listen_socket[listen_sockets].ev_tcp, NULL) < 0) {
 528                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 529                         abort();
 530                 }
 531
 532                 event_set(&listen_socket[listen_sockets].ev_udp,
 533                                   listen_socket[listen_sockets].udp,
 534                                   EV_READ|EV_PERSIST,
 535                                   handle_incoming_vpn_data, NULL);
 536                 if(event_add(&listen_socket[listen_sockets].ev_udp, NULL) < 0) {
 537                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 538                         abort();
 539                 }
 540
 541                 ifdebug(CONNECTIONS) {
 542                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 543                         logger(LOG_NOTICE, "Listening on %s", hostname);
 544                         free(hostname);
 545                 }
 546
 547                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 548                 listen_sockets++;
 549
 550                 if(listen_sockets >= MAXSOCKETS) {
 551                         logger(LOG_WARNING, "Maximum of %d listening sockets reached", MAXSOCKETS);
 552                         break;
 553                 }
 554         }
 555
 556         freeaddrinfo(ai);
 557
 558         if(listen_sockets)
 559                 logger(LOG_NOTICE, "Ready");
 560         else {
 561                 logger(LOG_ERR, "Unable to create any listening socket!");
 562                 return false;
 563         }
 564
 565         return true;
 566 }
 567
 568 /*
 569   initialize network
 570 */
 571 bool setup_network(void) {
 572         init_connections();
 573         init_subnets();
 574         init_nodes();
 575         init_edges();
 576         init_requests();
 577
 578         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 579                 if(pinginterval < 1) {
 580                         pinginterval = 86400;
 581                 }
 582         } else
 583                 pinginterval = 60;
 584
 585         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 586                 pingtimeout = 5;
 587         if(pingtimeout < 1 || pingtimeout > pinginterval)
 588                 pingtimeout = pinginterval;
 589
 590         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 591                 maxoutbufsize = 10 * MTU;
 592
 593         if(!setup_myself())
 594                 return false;
 595
 596         return true;
 597 }
 598
 599 /*
 600   close all open network connections
 601 */
 602 void close_network_connections(void) {
 603         splay_node_t *node, *next;
 604         connection_t *c;
 605         char *envp[5];
 606         int i;
 607
 608         for(node = connection_tree->head; node; node = next) {
 609                 next = node->next;
 610                 c = node->data;
 611                 c->outgoing = false;
 612                 terminate_connection(c, false);
 613         }
 614
 615         list_delete_list(outgoing_list);
 616
 617         if(myself && myself->connection) {
 618                 subnet_update(myself, NULL, false);
 619                 terminate_connection(myself->connection, false);
 620                 free_connection(myself->connection);
 621         }
 622
 623         for(i = 0; i < listen_sockets; i++) {
 624                 event_del(&listen_socket[i].ev_tcp);
 625                 event_del(&listen_socket[i].ev_udp);
 626                 close(listen_socket[i].tcp);
 627                 close(listen_socket[i].udp);
 628         }
 629
 630         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 631         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 632         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 633         xasprintf(&envp[3], "NAME=%s", myself->name);
 634         envp[4] = NULL;
 635
 636         exit_requests();
 637         exit_edges();
 638         exit_subnets();
 639         exit_nodes();
 640         exit_connections();
 641
 642         execute_script("tinc-down", envp);
 643
 644         if(myport) free(myport);
 645
 646         for(i = 0; i < 4; i++)
 647                 free(envp[i]);
 648
 649         close_device();
 650
 651         return;
 652 }