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 static bool read_rsa_private_key(void) {
  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(void) {
 147         if(timeout_initialized(&keyexpire_event)) {
 148                 ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys");
 149                 event_del(&keyexpire_event);
 150                 send_key_changed();
 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 static 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_major = PROT_MAJOR;
 243         myself->connection->protocol_minor = PROT_MINOR;
 244
 245         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 246                 logger(LOG_ERR, "Name for tinc daemon required!");
 247                 return false;
 248         }
 249
 250         if(!check_id(name)) {
 251                 logger(LOG_ERR, "Invalid name for myself!");
 252                 free(name);
 253                 return false;
 254         }
 255
 256         myself->name = name;
 257         myself->connection->name = xstrdup(name);
 258         xasprintf(&fname, "%s/hosts/%s", confbase, name);
 259         read_config_options(config_tree, name);
 260         read_config_file(config_tree, fname);
 261         free(fname);
 262
 263         if(!read_rsa_private_key())
 264                 return false;
 265
 266         if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
 267                 myport = xstrdup("655");
 268
 269         if(!atoi(myport)) {
 270                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 271                 sockaddr_t sa;
 272                 if(!ai || !ai->ai_addr)
 273                         return false;
 274                 free(myport);
 275                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 276                 sockaddr2str(&sa, NULL, &myport);
 277         }
 278
 279         /* Read in all the subnets specified in the host configuration file */
 280
 281         cfg = lookup_config(config_tree, "Subnet");
 282
 283         while(cfg) {
 284                 if(!get_config_subnet(cfg, &subnet))
 285                         return false;
 286
 287                 subnet_add(myself, subnet);
 288
 289                 cfg = lookup_config_next(config_tree, cfg);
 290         }
 291
 292         /* Check some options */
 293
 294         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 295                 myself->options |= OPTION_INDIRECT;
 296
 297         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 298                 myself->options |= OPTION_TCPONLY;
 299
 300         if(myself->options & OPTION_TCPONLY)
 301                 myself->options |= OPTION_INDIRECT;
 302
 303         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 304         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 305         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 306         strictsubnets |= tunnelserver;
 307
 308         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 309                 if(!strcasecmp(mode, "router"))
 310                         routing_mode = RMODE_ROUTER;
 311                 else if(!strcasecmp(mode, "switch"))
 312                         routing_mode = RMODE_SWITCH;
 313                 else if(!strcasecmp(mode, "hub"))
 314                         routing_mode = RMODE_HUB;
 315                 else {
 316                         logger(LOG_ERR, "Invalid routing mode!");
 317                         return false;
 318                 }
 319                 free(mode);
 320         }
 321
 322         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 323                 if(!strcasecmp(mode, "off"))
 324                         forwarding_mode = FMODE_OFF;
 325                 else if(!strcasecmp(mode, "internal"))
 326                         forwarding_mode = FMODE_INTERNAL;
 327                 else if(!strcasecmp(mode, "kernel"))
 328                         forwarding_mode = FMODE_KERNEL;
 329                 else {
 330                         logger(LOG_ERR, "Invalid forwarding mode!");
 331                         return false;
 332                 }
 333                 free(mode);
 334         }
 335
 336         choice = true;
 337         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 338         if(choice)
 339                 myself->options |= OPTION_PMTU_DISCOVERY;
 340
 341         choice = true;
 342         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 343         if(choice)
 344                 myself->options |= OPTION_CLAMP_MSS;
 345
 346         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 347
 348 #if !defined(SOL_IP) || !defined(IP_TOS)
 349         if(priorityinheritance)
 350                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 351 #endif
 352
 353         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 354                 macexpire = 600;
 355
 356         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 357                 if(maxtimeout <= 0) {
 358                         logger(LOG_ERR, "Bogus maximum timeout!");
 359                         return false;
 360                 }
 361         } else
 362                 maxtimeout = 900;
 363
 364         if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 365                 if(udp_rcvbuf <= 0) {
 366                         logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
 367                         return false;
 368                 }
 369         }
 370
 371         if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
 372                 if(udp_sndbuf <= 0) {
 373                         logger(LOG_ERR, "UDPSndBuf cannot be negative!");
 374                         return false;
 375                 }
 376         }
 377
 378         if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
 379                 if(replaywin_int < 0) {
 380                         logger(LOG_ERR, "ReplayWindow cannot be negative!");
 381                         return false;
 382                 }
 383                 replaywin = (unsigned)replaywin_int;
 384         }
 385
 386         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 387                 if(!strcasecmp(afname, "IPv4"))
 388                         addressfamily = AF_INET;
 389                 else if(!strcasecmp(afname, "IPv6"))
 390                         addressfamily = AF_INET6;
 391                 else if(!strcasecmp(afname, "any"))
 392                         addressfamily = AF_UNSPEC;
 393                 else {
 394                         logger(LOG_ERR, "Invalid address family!");
 395                         return false;
 396                 }
 397                 free(afname);
 398         }
 399
 400         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 401
 402         /* Generate packet encryption key */
 403
 404         if(!get_config_string(lookup_config(config_tree, "Cipher"), &cipher))
 405                 cipher = xstrdup("blowfish");
 406
 407         if(!cipher_open_by_name(&myself->incipher, cipher)) {
 408                 logger(LOG_ERR, "Unrecognized cipher type!");
 409                 return false;
 410         }
 411
 412         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 413                 keylifetime = 3600;
 414
 415         regenerate_key();
 416
 417         /* Check if we want to use message authentication codes... */
 418
 419         if(!get_config_string(lookup_config(config_tree, "Digest"), &digest))
 420                 digest = xstrdup("sha1");
 421
 422         int maclength = 4;
 423         get_config_int(lookup_config(config_tree, "MACLength"), &maclength);
 424
 425         if(maclength < 0) {
 426                 logger(LOG_ERR, "Bogus MAC length!");
 427                 return false;
 428         }
 429
 430         if(!digest_open_by_name(&myself->indigest, digest, maclength)) {
 431                 logger(LOG_ERR, "Unrecognized digest type!");
 432                 return false;
 433         }
 434
 435         /* Compression */
 436
 437         if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
 438                 if(myself->incompression < 0 || myself->incompression > 11) {
 439                         logger(LOG_ERR, "Bogus compression level!");
 440                         return false;
 441                 }
 442         } else
 443                 myself->incompression = 0;
 444
 445         myself->connection->outcompression = 0;
 446
 447         /* Done */
 448
 449         myself->nexthop = myself;
 450         myself->via = myself;
 451         myself->status.reachable = true;
 452         node_add(myself);
 453
 454         graph();
 455
 456         if(strictsubnets)
 457                 load_all_subnets();
 458
 459         /* Open device */
 460
 461         if(!setup_device())
 462                 return false;
 463
 464         if(device_fd >= 0) {
 465                 event_set(&device_ev, device_fd, EV_READ|EV_PERSIST, handle_device_data, NULL);
 466
 467                 if (event_add(&device_ev, NULL) < 0) {
 468                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 469                         close_device();
 470                         return false;
 471                 }
 472         }
 473
 474         /* Run tinc-up script to further initialize the tap interface */
 475         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 476         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 477         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 478         xasprintf(&envp[3], "NAME=%s", myself->name);
 479         envp[4] = NULL;
 480
 481         execute_script("tinc-up", envp);
 482
 483         for(i = 0; i < 4; i++)
 484                 free(envp[i]);
 485
 486         /* Run subnet-up scripts for our own subnets */
 487
 488         subnet_update(myself, NULL, true);
 489
 490         /* Open sockets */
 491
 492         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 493
 494         hint.ai_family = addressfamily;
 495         hint.ai_socktype = SOCK_STREAM;
 496         hint.ai_protocol = IPPROTO_TCP;
 497         hint.ai_flags = AI_PASSIVE;
 498
 499         err = getaddrinfo(address, myport, &hint, &ai);
 500
 501         if(err || !ai) {
 502                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 503                            gai_strerror(err));
 504                 return false;
 505         }
 506
 507         listen_sockets = 0;
 508
 509         for(aip = ai; aip; aip = aip->ai_next) {
 510                 listen_socket[listen_sockets].tcp =
 511                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 512
 513                 if(listen_socket[listen_sockets].tcp < 0)
 514                         continue;
 515
 516                 listen_socket[listen_sockets].udp =
 517                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 518
 519                 if(listen_socket[listen_sockets].udp < 0) {
 520                         close(listen_socket[listen_sockets].tcp);
 521                         continue;
 522                 }
 523
 524                 event_set(&listen_socket[listen_sockets].ev_tcp,
 525                                   listen_socket[listen_sockets].tcp,
 526                                   EV_READ|EV_PERSIST,
 527                                   handle_new_meta_connection, NULL);
 528                 if(event_add(&listen_socket[listen_sockets].ev_tcp, NULL) < 0) {
 529                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 530                         abort();
 531                 }
 532
 533                 event_set(&listen_socket[listen_sockets].ev_udp,
 534                                   listen_socket[listen_sockets].udp,
 535                                   EV_READ|EV_PERSIST,
 536                                   handle_incoming_vpn_data, NULL);
 537                 if(event_add(&listen_socket[listen_sockets].ev_udp, NULL) < 0) {
 538                         logger(LOG_ERR, "event_add failed: %s", strerror(errno));
 539                         abort();
 540                 }
 541
 542                 ifdebug(CONNECTIONS) {
 543                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 544                         logger(LOG_NOTICE, "Listening on %s", hostname);
 545                         free(hostname);
 546                 }
 547
 548                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 549                 listen_sockets++;
 550
 551                 if(listen_sockets >= MAXSOCKETS) {
 552                         logger(LOG_WARNING, "Maximum of %d listening sockets reached", MAXSOCKETS);
 553                         break;
 554                 }
 555         }
 556
 557         freeaddrinfo(ai);
 558
 559         if(listen_sockets)
 560                 logger(LOG_NOTICE, "Ready");
 561         else {
 562                 logger(LOG_ERR, "Unable to create any listening socket!");
 563                 return false;
 564         }
 565
 566         return true;
 567 }
 568
 569 /*
 570   initialize network
 571 */
 572 bool setup_network(void) {
 573         init_connections();
 574         init_subnets();
 575         init_nodes();
 576         init_edges();
 577         init_requests();
 578
 579         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 580                 if(pinginterval < 1) {
 581                         pinginterval = 86400;
 582                 }
 583         } else
 584                 pinginterval = 60;
 585
 586         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 587                 pingtimeout = 5;
 588         if(pingtimeout < 1 || pingtimeout > pinginterval)
 589                 pingtimeout = pinginterval;
 590
 591         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 592                 maxoutbufsize = 10 * MTU;
 593
 594         if(!setup_myself())
 595                 return false;
 596
 597         return true;
 598 }
 599
 600 /*
 601   close all open network connections
 602 */
 603 void close_network_connections(void) {
 604         splay_node_t *node, *next;
 605         connection_t *c;
 606         char *envp[5];
 607         int i;
 608
 609         for(node = connection_tree->head; node; node = next) {
 610                 next = node->next;
 611                 c = node->data;
 612                 c->outgoing = NULL;
 613                 terminate_connection(c, false);
 614         }
 615
 616         list_delete_list(outgoing_list);
 617
 618         if(myself && myself->connection) {
 619                 subnet_update(myself, NULL, false);
 620                 terminate_connection(myself->connection, false);
 621                 free_connection(myself->connection);
 622         }
 623
 624         for(i = 0; i < listen_sockets; i++) {
 625                 event_del(&listen_socket[i].ev_tcp);
 626                 event_del(&listen_socket[i].ev_udp);
 627                 close(listen_socket[i].tcp);
 628                 close(listen_socket[i].udp);
 629         }
 630
 631         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 632         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 633         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 634         xasprintf(&envp[3], "NAME=%s", myself->name);
 635         envp[4] = NULL;
 636
 637         exit_requests();
 638         exit_edges();
 639         exit_subnets();
 640         exit_nodes();
 641         exit_connections();
 642
 643         execute_script("tinc-down", envp);
 644
 645         if(myport) free(myport);
 646
 647         for(i = 0; i < 4; i++)
 648                 free(envp[i]);
 649
 650         close_device();
 651
 652         return;
 653 }