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 "splay_tree.h"
  25 #include "cipher.h"
  26 #include "conf.h"
  27 #include "connection.h"
  28 #include "control.h"
  29 #include "device.h"
  30 #include "digest.h"
  31 #include "graph.h"
  32 #include "logger.h"
  33 #include "net.h"
  34 #include "netutl.h"
  35 #include "process.h"
  36 #include "protocol.h"
  37 #include "route.h"
  38 #include "rsa.h"
  39 #include "subnet.h"
  40 #include "utils.h"
  41 #include "xalloc.h"
  42
  43 char *myport;
  44 static struct event device_ev;
  45
  46 bool read_rsa_public_key(connection_t *c) {
  47         FILE *fp;
  48         char *fname;
  49         char *n;
  50         bool result;
  51
  52         /* First, check for simple PublicKey statement */
  53
  54         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &n)) {
  55                 result = rsa_set_hex_public_key(&c->rsa, n, "FFFF");
  56                 free(n);
  57                 return result;
  58         }
  59
  60         /* Else, check for PublicKeyFile statement and read it */
  61
  62         if(!get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
  63                 xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
  64
  65         fp = fopen(fname, "r");
  66
  67         if(!fp) {
  68                 logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  69                            fname, strerror(errno));
  70                 free(fname);
  71                 return false;
  72         }
  73
  74         result = rsa_read_pem_public_key(&c->rsa, fp);
  75         fclose(fp);
  76
  77         if(!result)
  78                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s", fname, strerror(errno));
  79         free(fname);
  80         return result;
  81 }
  82
  83 bool read_rsa_private_key() {
  84         FILE *fp;
  85         char *fname;
  86         char *n, *d;
  87         bool result;
  88
  89         /* First, check for simple PrivateKey statement */
  90
  91         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &d)) {
  92                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &n)) {
  93                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
  94                         free(d);
  95                         return false;
  96                 }
  97                 result = rsa_set_hex_private_key(&myself->connection->rsa, n, "FFFF", d);
  98                 free(n);
  99                 free(d);
 100                 return true;
 101         }
 102
 103         /* Else, check for PrivateKeyFile statement and read it */
 104
 105         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 106                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 107
 108         fp = fopen(fname, "r");
 109
 110         if(!fp) {
 111                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 112                            fname, strerror(errno));
 113                 free(fname);
 114                 return false;
 115         }
 116
 117 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 118         struct stat s;
 119
 120         if(fstat(fileno(fp), &s)) {
 121                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'", fname, strerror(errno));
 122                 free(fname);
 123                 return false;
 124         }
 125
 126         if(s.st_mode & ~0100700)
 127                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 128 #endif
 129
 130         result = rsa_read_pem_private_key(&myself->connection->rsa, fp);
 131         fclose(fp);
 132
 133         if(!result)
 134                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s", fname, strerror(errno));
 135         free(fname);
 136         return result;
 137 }
 138
 139 static struct event keyexpire_event;
 140
 141 static void keyexpire_handler(int fd, short events, void *data) {
 142         regenerate_key();
 143 }
 144
 145 void regenerate_key() {
 146         if(timeout_initialized(&keyexpire_event)) {
 147                 ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys");
 148                 event_del(&keyexpire_event);
 149                 send_key_changed(broadcast, myself);
 150         } else {
 151                 timeout_set(&keyexpire_event, keyexpire_handler, NULL);
 152         }
 153
 154         event_add(&keyexpire_event, &(struct timeval){keylifetime, 0});
 155 }
 156
 157 /*
 158   Configure node_t myself and set up the local sockets (listen only)
 159 */
 160 bool setup_myself(void) {
 161         config_t *cfg;
 162         subnet_t *subnet;
 163         char *name, *hostname, *mode, *afname, *cipher, *digest;
 164         char *address = NULL;
 165         char *envp[5];
 166         struct addrinfo *ai, *aip, hint = {0};
 167         bool choice;
 168         int i, err;
 169
 170         myself = new_node();
 171         myself->connection = new_connection();
 172         init_configuration(&myself->connection->config_tree);
 173
 174         xasprintf(&myself->hostname, "MYSELF");
 175         xasprintf(&myself->connection->hostname, "MYSELF");
 176
 177         myself->connection->options = 0;
 178         myself->connection->protocol_version = PROT_CURRENT;
 179
 180         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 181                 logger(LOG_ERR, "Name for tinc daemon required!");
 182                 return false;
 183         }
 184
 185         if(!check_id(name)) {
 186                 logger(LOG_ERR, "Invalid name for myself!");
 187                 free(name);
 188                 return false;
 189         }
 190
 191         myself->name = name;
 192         myself->connection->name = xstrdup(name);
 193
 194         if(!read_connection_config(myself->connection)) {
 195                 logger(LOG_ERR, "Cannot open host configuration file for myself!");
 196                 return false;
 197         }
 198
 199         if(!read_rsa_private_key())
 200                 return false;
 201
 202         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
 203                 xasprintf(&myport, "655");
 204
 205         /* Read in all the subnets specified in the host configuration file */
 206
 207         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 208
 209         while(cfg) {
 210                 if(!get_config_subnet(cfg, &subnet))
 211                         return false;
 212
 213                 subnet_add(myself, subnet);
 214
 215                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 216         }
 217
 218         /* Check some options */
 219
 220         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 221                 myself->options |= OPTION_INDIRECT;
 222
 223         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 224                 myself->options |= OPTION_TCPONLY;
 225
 226         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
 227                 myself->options |= OPTION_INDIRECT;
 228
 229         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
 230                 myself->options |= OPTION_TCPONLY;
 231
 232         if(myself->options & OPTION_TCPONLY)
 233                 myself->options |= OPTION_INDIRECT;
 234
 235         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 236
 237         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 238                 if(!strcasecmp(mode, "router"))
 239                         routing_mode = RMODE_ROUTER;
 240                 else if(!strcasecmp(mode, "switch"))
 241                         routing_mode = RMODE_SWITCH;
 242                 else if(!strcasecmp(mode, "hub"))
 243                         routing_mode = RMODE_HUB;
 244                 else {
 245                         logger(LOG_ERR, "Invalid routing mode!");
 246                         return false;
 247                 }
 248                 free(mode);
 249         } else
 250                 routing_mode = RMODE_ROUTER;
 251
 252         // Enable PMTUDiscovery by default if we are in router mode.
 253
 254         choice = routing_mode == RMODE_ROUTER;
 255         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
 256         if(choice)
 257                 myself->options |= OPTION_PMTU_DISCOVERY;
 258
 259         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 260
 261 #if !defined(SOL_IP) || !defined(IP_TOS)
 262         if(priorityinheritance)
 263                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 264 #endif
 265
 266         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 267                 macexpire = 600;
 268
 269         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 270                 if(maxtimeout <= 0) {
 271                         logger(LOG_ERR, "Bogus maximum timeout!");
 272                         return false;
 273                 }
 274         } else
 275                 maxtimeout = 900;
 276
 277         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 278                 if(!strcasecmp(afname, "IPv4"))
 279                         addressfamily = AF_INET;
 280                 else if(!strcasecmp(afname, "IPv6"))
 281                         addressfamily = AF_INET6;
 282                 else if(!strcasecmp(afname, "any"))
 283                         addressfamily = AF_UNSPEC;
 284                 else {
 285                         logger(LOG_ERR, "Invalid address family!");
 286                         return false;
 287                 }
 288                 free(afname);
 289         }
 290
 291         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 292
 293         /* Generate packet encryption key */
 294
 295         if(!get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher))
 296                 cipher = xstrdup("aes256");
 297
 298         if(!cipher_open_by_name(&myself->incipher, cipher)) {
 299                 logger(LOG_ERR, "Unrecognized cipher type!");
 300                 return false;
 301         }
 302
 303         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 304                 keylifetime = 3600;
 305
 306         regenerate_key();
 307
 308         /* Check if we want to use message authentication codes... */
 309
 310         if(!get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest))
 311                 digest = xstrdup("sha256");
 312
 313         int maclength = 4;
 314         get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &maclength);
 315
 316         if(maclength < 0) {
 317                 logger(LOG_ERR, "Bogus MAC length!");
 318                 return false;
 319         }
 320
 321         if(!digest_open_by_name(&myself->indigest, digest, maclength)) {
 322                 logger(LOG_ERR, "Unrecognized digest type!");
 323                 return false;
 324         }
 325
 326         /* Compression */
 327
 328         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
 329                 if(myself->incompression < 0 || myself->incompression > 11) {
 330                         logger(LOG_ERR, "Bogus compression level!");
 331                         return false;
 332                 }
 333         } else
 334                 myself->incompression = 0;
 335
 336         myself->connection->outcompression = 0;
 337
 338         /* Done */
 339
 340         myself->nexthop = myself;
 341         myself->via = myself;
 342         myself->status.reachable = true;
 343         node_add(myself);
 344
 345         graph();
 346
 347         /* Open device */
 348
 349         if(!setup_device())
 350                 return false;
 351
 352         event_set(&device_ev, device_fd, EV_READ|EV_PERSIST, handle_device_data, NULL);
 353
 354         if (event_add(&device_ev, NULL) < 0) {
 355                 logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 356                 close_device();
 357                 return false;
 358         }
 359
 360         /* Run tinc-up script to further initialize the tap interface */
 361         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 362         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 363         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 364         xasprintf(&envp[3], "NAME=%s", myself->name);
 365         envp[4] = NULL;
 366
 367         execute_script("tinc-up", envp);
 368
 369         for(i = 0; i < 5; i++)
 370                 free(envp[i]);
 371
 372         /* Run subnet-up scripts for our own subnets */
 373
 374         subnet_update(myself, NULL, true);
 375
 376         /* Open sockets */
 377
 378         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 379
 380         hint.ai_family = addressfamily;
 381         hint.ai_socktype = SOCK_STREAM;
 382         hint.ai_protocol = IPPROTO_TCP;
 383         hint.ai_flags = AI_PASSIVE;
 384
 385         err = getaddrinfo(address, myport, &hint, &ai);
 386
 387         if(err || !ai) {
 388                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 389                            gai_strerror(err));
 390                 return false;
 391         }
 392
 393         listen_sockets = 0;
 394
 395         for(aip = ai; aip; aip = aip->ai_next) {
 396                 listen_socket[listen_sockets].tcp =
 397                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 398
 399                 if(listen_socket[listen_sockets].tcp < 0)
 400                         continue;
 401
 402                 listen_socket[listen_sockets].udp =
 403                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 404
 405                 if(listen_socket[listen_sockets].udp < 0) {
 406                         close(listen_socket[listen_sockets].tcp);
 407                         continue;
 408                 }
 409
 410                 event_set(&listen_socket[listen_sockets].ev_tcp,
 411                                   listen_socket[listen_sockets].tcp,
 412                                   EV_READ|EV_PERSIST,
 413                                   handle_new_meta_connection, NULL);
 414                 if(event_add(&listen_socket[listen_sockets].ev_tcp, NULL) < 0) {
 415                         logger(LOG_EMERG, "event_add failed: %s", strerror(errno));
 416                         abort();
 417                 }
 418
 419                 event_set(&listen_socket[listen_sockets].ev_udp,
 420                                   listen_socket[listen_sockets].udp,
 421                                   EV_READ|EV_PERSIST,
 422                                   handle_incoming_vpn_data, NULL);
 423                 if(event_add(&listen_socket[listen_sockets].ev_udp, NULL) < 0) {
 424                         logger(LOG_EMERG, "event_add failed: %s", strerror(errno));
 425                         abort();
 426                 }
 427
 428                 ifdebug(CONNECTIONS) {
 429                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 430                         logger(LOG_NOTICE, "Listening on %s", hostname);
 431                         free(hostname);
 432                 }
 433
 434                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 435                 listen_sockets++;
 436
 437                 if(listen_sockets >= MAXSOCKETS) {
 438                         logger(LOG_WARNING, "Maximum of %d listening sockets reached", MAXSOCKETS);
 439                         break;
 440                 }
 441         }
 442
 443         freeaddrinfo(ai);
 444
 445         if(listen_sockets)
 446                 logger(LOG_NOTICE, "Ready");
 447         else {
 448                 logger(LOG_ERR, "Unable to create any listening socket!");
 449                 return false;
 450         }
 451
 452         return true;
 453 }
 454
 455 /*
 456   initialize network
 457 */
 458 bool setup_network(void) {
 459         init_connections();
 460         init_subnets();
 461         init_nodes();
 462         init_edges();
 463         init_requests();
 464
 465         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 466                 if(pinginterval < 1) {
 467                         pinginterval = 86400;
 468                 }
 469         } else
 470                 pinginterval = 60;
 471
 472         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 473                 pingtimeout = 5;
 474         if(pingtimeout < 1 || pingtimeout > pinginterval)
 475                 pingtimeout = pinginterval;
 476
 477         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 478                 maxoutbufsize = 10 * MTU;
 479
 480         if(!setup_myself())
 481                 return false;
 482
 483         return true;
 484 }
 485
 486 /*
 487   close all open network connections
 488 */
 489 void close_network_connections(void) {
 490         splay_node_t *node, *next;
 491         connection_t *c;
 492         char *envp[5];
 493         int i;
 494
 495         for(node = connection_tree->head; node; node = next) {
 496                 next = node->next;
 497                 c = node->data;
 498                 c->outgoing = false;
 499                 terminate_connection(c, false);
 500         }
 501
 502         list_delete_list(outgoing_list);
 503
 504         if(myself && myself->connection) {
 505                 subnet_update(myself, NULL, false);
 506                 terminate_connection(myself->connection, false);
 507                 free_connection(myself->connection);
 508         }
 509
 510         for(i = 0; i < listen_sockets; i++) {
 511                 event_del(&listen_socket[i].ev_tcp);
 512                 event_del(&listen_socket[i].ev_udp);
 513                 close(listen_socket[i].tcp);
 514                 close(listen_socket[i].udp);
 515         }
 516
 517         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 518         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 519         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 520         xasprintf(&envp[3], "NAME=%s", myself->name);
 521         envp[4] = NULL;
 522
 523         exit_requests();
 524         exit_edges();
 525         exit_subnets();
 526         exit_nodes();
 527         exit_connections();
 528
 529         execute_script("tinc-down", envp);
 530
 531         if(myport) free(myport);
 532
 533         for(i = 0; i < 4; i++)
 534                 free(envp[i]);
 535
 536         close_device();
 537
 538         return;
 539 }