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                   2000-2021 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 "cipher.h"
  26 #include "conf_net.h"
  27 #include "conf.h"
  28 #include "connection.h"
  29 #include "compression.h"
  30 #include "control.h"
  31 #include "crypto.h"
  32 #include "device.h"
  33 #include "digest.h"
  34 #include "ecdsa.h"
  35 #include "graph.h"
  36 #include "logger.h"
  37 #include "names.h"
  38 #include "net.h"
  39 #include "netutl.h"
  40 #include "process.h"
  41 #include "protocol.h"
  42 #include "route.h"
  43 #include "script.h"
  44 #include "subnet.h"
  45 #include "utils.h"
  46 #include "xalloc.h"
  47 #include "keys.h"
  48 #include "sandbox.h"
  49
  50 #ifdef HAVE_MINIUPNPC
  51 #include "upnp.h"
  52 #endif
  53
  54 ports_t myport;
  55 static io_t device_io;
  56 devops_t devops;
  57 bool device_standby = false;
  58
  59 char *proxyhost = NULL;
  60 char *proxyport = NULL;
  61 char *proxyuser = NULL;
  62 char *proxypass = NULL;
  63
  64 proxytype_t proxytype;
  65 bool autoconnect;
  66 bool disablebuggypeers;
  67
  68 char *scriptinterpreter;
  69 char *scriptextension;
  70
  71 bool node_read_ecdsa_public_key(node_t *n) {
  72         if(ecdsa_active(n->ecdsa)) {
  73                 return true;
  74         }
  75
  76         FILE *fp;
  77         char *pubname = NULL;
  78         char *p;
  79
  80         splay_tree_t config;
  81         init_configuration(&config);
  82
  83         if(!read_host_config(&config, n->name, true)) {
  84                 goto exit;
  85         }
  86
  87         /* First, check for simple Ed25519PublicKey statement */
  88
  89         if(get_config_string(lookup_config(&config, "Ed25519PublicKey"), &p)) {
  90                 n->ecdsa = ecdsa_set_base64_public_key(p);
  91                 free(p);
  92                 goto exit;
  93         }
  94
  95         /* Else, check for Ed25519PublicKeyFile statement and read it */
  96
  97         if(!get_config_string(lookup_config(&config, "Ed25519PublicKeyFile"), &pubname)) {
  98                 xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, n->name);
  99         }
 100
 101         fp = fopen(pubname, "r");
 102
 103         if(!fp) {
 104                 goto exit;
 105         }
 106
 107         n->ecdsa = ecdsa_read_pem_public_key(fp);
 108         fclose(fp);
 109
 110 exit:
 111         splay_empty_tree(&config);
 112         free(pubname);
 113         return n->ecdsa;
 114 }
 115
 116 static bool read_invitation_key(void) {
 117         FILE *fp;
 118         char fname[PATH_MAX];
 119
 120         if(invitation_key) {
 121                 ecdsa_free(invitation_key);
 122                 invitation_key = NULL;
 123         }
 124
 125         snprintf(fname, sizeof(fname), "%s" SLASH "invitations" SLASH "ed25519_key.priv", confbase);
 126
 127         fp = fopen(fname, "r");
 128
 129         if(fp) {
 130                 invitation_key = ecdsa_read_pem_private_key(fp);
 131                 fclose(fp);
 132
 133                 if(!invitation_key) {
 134                         logger(DEBUG_ALWAYS, LOG_ERR, "Reading Ed25519 private key file `%s' failed", fname);
 135                 }
 136         }
 137
 138         return invitation_key;
 139 }
 140
 141 #ifndef DISABLE_LEGACY
 142 static timeout_t keyexpire_timeout;
 143
 144 static void keyexpire_handler(void *data) {
 145         regenerate_key();
 146         timeout_set(data, &(struct timeval) {
 147                 keylifetime, jitter()
 148         });
 149 }
 150 #endif
 151
 152 void regenerate_key(void) {
 153         logger(DEBUG_STATUS, LOG_INFO, "Expiring symmetric keys");
 154         send_key_changed();
 155
 156         for splay_each(node_t, n, &node_tree) {
 157                 n->status.validkey_in = false;
 158         }
 159 }
 160
 161 void load_all_nodes(void) {
 162         DIR *dir;
 163         struct dirent *ent;
 164         char dname[PATH_MAX];
 165
 166         snprintf(dname, sizeof(dname), "%s" SLASH "hosts", confbase);
 167         dir = opendir(dname);
 168
 169         if(!dir) {
 170                 logger(DEBUG_ALWAYS, LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 171                 return;
 172         }
 173
 174         while((ent = readdir(dir))) {
 175                 if(!check_id(ent->d_name)) {
 176                         continue;
 177                 }
 178
 179                 node_t *n = lookup_node(ent->d_name);
 180
 181                 splay_tree_t config;
 182                 init_configuration(&config);
 183                 read_config_options(&config, ent->d_name);
 184                 read_host_config(&config, ent->d_name, true);
 185
 186                 if(!n) {
 187                         n = new_node();
 188                         n->name = xstrdup(ent->d_name);
 189                         node_add(n);
 190                 }
 191
 192                 if(strictsubnets) {
 193                         for(config_t *cfg = lookup_config(&config, "Subnet"); cfg; cfg = lookup_config_next(&config, cfg)) {
 194                                 subnet_t *s, *s2;
 195
 196                                 if(!get_config_subnet(cfg, &s)) {
 197                                         continue;
 198                                 }
 199
 200                                 if((s2 = lookup_subnet(n, s))) {
 201                                         s2->expires = -1;
 202                                         free(s);
 203                                 } else {
 204                                         subnet_add(n, s);
 205                                 }
 206                         }
 207                 }
 208
 209                 if(lookup_config(&config, "Address")) {
 210                         n->status.has_address = true;
 211                 }
 212
 213                 splay_empty_tree(&config);
 214         }
 215
 216         closedir(dir);
 217 }
 218
 219 char *get_name(void) {
 220         char *name = NULL;
 221         char *returned_name;
 222
 223         get_config_string(lookup_config(&config_tree, "Name"), &name);
 224
 225         if(!name) {
 226                 return NULL;
 227         }
 228
 229         returned_name = replace_name(name);
 230         free(name);
 231         return returned_name;
 232 }
 233
 234 static void read_interpreter(void) {
 235         char *interpreter = NULL;
 236         get_config_string(lookup_config(&config_tree, "ScriptsInterpreter"), &interpreter);
 237
 238         if(!interpreter || (sandbox_can(START_PROCESSES, AFTER_SANDBOX) && sandbox_can(USE_NEW_PATHS, AFTER_SANDBOX))) {
 239                 free(scriptinterpreter);
 240                 scriptinterpreter = interpreter;
 241                 return;
 242         }
 243
 244         if(!string_eq(interpreter, scriptinterpreter)) {
 245                 logger(DEBUG_ALWAYS, LOG_NOTICE, "Not changing ScriptsInterpreter because of sandbox.");
 246         }
 247
 248         free(interpreter);
 249 }
 250
 251 bool setup_myself_reloadable(void) {
 252         read_interpreter();
 253
 254         free(scriptextension);
 255
 256         if(!get_config_string(lookup_config(&config_tree, "ScriptsExtension"), &scriptextension)) {
 257                 scriptextension = xstrdup("");
 258         }
 259
 260         char *proxy = NULL;
 261
 262         get_config_string(lookup_config(&config_tree, "Proxy"), &proxy);
 263
 264         if(proxy) {
 265                 char *space;
 266
 267                 if((space = strchr(proxy, ' '))) {
 268                         *space++ = 0;
 269                 }
 270
 271                 if(!strcasecmp(proxy, "none")) {
 272                         proxytype = PROXY_NONE;
 273                 } else if(!strcasecmp(proxy, "socks4")) {
 274                         proxytype = PROXY_SOCKS4;
 275                 } else if(!strcasecmp(proxy, "socks4a")) {
 276                         proxytype = PROXY_SOCKS4A;
 277                 } else if(!strcasecmp(proxy, "socks5")) {
 278                         proxytype = PROXY_SOCKS5;
 279                 } else if(!strcasecmp(proxy, "http")) {
 280                         proxytype = PROXY_HTTP;
 281                 } else if(!strcasecmp(proxy, "exec")) {
 282                         if(sandbox_can(START_PROCESSES, AFTER_SANDBOX)) {
 283                                 proxytype = PROXY_EXEC;
 284                         } else {
 285                                 logger(DEBUG_ALWAYS, LOG_ERR, "Cannot use exec proxies with current sandbox level.");
 286                                 return false;
 287                         }
 288                 } else {
 289                         logger(DEBUG_ALWAYS, LOG_ERR, "Unknown proxy type %s!", proxy);
 290                         free_string(proxy);
 291                         return false;
 292                 }
 293
 294                 free(proxyhost);
 295                 proxyhost = NULL;
 296
 297                 free(proxyport);
 298                 proxyport = NULL;
 299
 300                 free_string(proxyuser);
 301                 proxyuser = NULL;
 302
 303                 free_string(proxypass);
 304                 proxypass = NULL;
 305
 306                 switch(proxytype) {
 307                 case PROXY_NONE:
 308                 default:
 309                         break;
 310
 311                 case PROXY_EXEC:
 312                         if(!space || !*space) {
 313                                 logger(DEBUG_ALWAYS, LOG_ERR, "Argument expected for proxy type exec!");
 314                                 free_string(proxy);
 315                                 return false;
 316                         }
 317
 318                         if(!sandbox_can(USE_NEW_PATHS, AFTER_SANDBOX)) {
 319                                 logger(DEBUG_ALWAYS, LOG_NOTICE, "Changed exec proxy may fail to work because of sandbox.");
 320                         }
 321
 322                         proxyhost = xstrdup(space);
 323                         break;
 324
 325                 case PROXY_SOCKS4:
 326                 case PROXY_SOCKS4A:
 327                 case PROXY_SOCKS5:
 328                 case PROXY_HTTP:
 329                         proxyhost = space;
 330
 331                         if(space && (space = strchr(space, ' '))) {
 332                                 *space++ = 0, proxyport = space;
 333                         }
 334
 335                         if(!proxyhost || !*proxyhost || !proxyport || !*proxyport) {
 336                                 logger(DEBUG_ALWAYS, LOG_ERR, "Host and port argument expected for proxy!");
 337                                 proxyport = NULL;
 338                                 proxyhost = NULL;
 339                                 free_string(proxy);
 340                                 return false;
 341                         }
 342
 343                         if(space && (space = strchr(space, ' '))) {
 344                                 *space++ = 0, proxyuser = space;
 345                         }
 346
 347                         if(space && (space = strchr(space, ' '))) {
 348                                 *space++ = 0, proxypass = space;
 349                         }
 350
 351                         proxyhost = xstrdup(proxyhost);
 352                         proxyport = xstrdup(proxyport);
 353
 354                         if(proxyuser && *proxyuser) {
 355                                 proxyuser = xstrdup(proxyuser);
 356                         }
 357
 358                         if(proxypass && *proxypass) {
 359                                 proxypass = xstrdup(proxypass);
 360                         }
 361
 362                         break;
 363                 }
 364
 365                 free_string(proxy);
 366         }
 367
 368         bool choice;
 369
 370         if(get_config_bool(lookup_config(&config_tree, "IndirectData"), &choice) && choice) {
 371                 myself->options |= OPTION_INDIRECT;
 372         }
 373
 374         if(get_config_bool(lookup_config(&config_tree, "TCPOnly"), &choice) && choice) {
 375                 myself->options |= OPTION_TCPONLY;
 376         }
 377
 378         if(myself->options & OPTION_TCPONLY) {
 379                 myself->options |= OPTION_INDIRECT;
 380         }
 381
 382         get_config_bool(lookup_config(&config_tree, "UDPDiscovery"), &udp_discovery);
 383         get_config_int(lookup_config(&config_tree, "UDPDiscoveryKeepaliveInterval"), &udp_discovery_keepalive_interval);
 384         get_config_int(lookup_config(&config_tree, "UDPDiscoveryInterval"), &udp_discovery_interval);
 385         get_config_int(lookup_config(&config_tree, "UDPDiscoveryTimeout"), &udp_discovery_timeout);
 386
 387         get_config_int(lookup_config(&config_tree, "MTUInfoInterval"), &mtu_info_interval);
 388         get_config_int(lookup_config(&config_tree, "UDPInfoInterval"), &udp_info_interval);
 389
 390         get_config_bool(lookup_config(&config_tree, "DirectOnly"), &directonly);
 391         get_config_bool(lookup_config(&config_tree, "LocalDiscovery"), &localdiscovery);
 392
 393         char *rmode = NULL;
 394
 395         if(get_config_string(lookup_config(&config_tree, "Mode"), &rmode)) {
 396                 if(!strcasecmp(rmode, "router")) {
 397                         routing_mode = RMODE_ROUTER;
 398                 } else if(!strcasecmp(rmode, "switch")) {
 399                         routing_mode = RMODE_SWITCH;
 400                 } else if(!strcasecmp(rmode, "hub")) {
 401                         routing_mode = RMODE_HUB;
 402                 } else {
 403                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid routing mode!");
 404                         free(rmode);
 405                         return false;
 406                 }
 407
 408                 free(rmode);
 409         }
 410
 411         char *fmode = NULL;
 412
 413         if(get_config_string(lookup_config(&config_tree, "Forwarding"), &fmode)) {
 414                 if(!strcasecmp(fmode, "off")) {
 415                         forwarding_mode = FMODE_OFF;
 416                 } else if(!strcasecmp(fmode, "internal")) {
 417                         forwarding_mode = FMODE_INTERNAL;
 418                 } else if(!strcasecmp(fmode, "kernel")) {
 419                         forwarding_mode = FMODE_KERNEL;
 420                 } else {
 421                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid forwarding mode!");
 422                         free(fmode);
 423                         return false;
 424                 }
 425
 426                 free(fmode);
 427         }
 428
 429         choice = !(myself->options & OPTION_TCPONLY);
 430         get_config_bool(lookup_config(&config_tree, "PMTUDiscovery"), &choice);
 431
 432         if(choice) {
 433                 myself->options |= OPTION_PMTU_DISCOVERY;
 434         }
 435
 436         choice = true;
 437         get_config_bool(lookup_config(&config_tree, "ClampMSS"), &choice);
 438
 439         if(choice) {
 440                 myself->options |= OPTION_CLAMP_MSS;
 441         }
 442
 443         get_config_bool(lookup_config(&config_tree, "PriorityInheritance"), &priorityinheritance);
 444         get_config_bool(lookup_config(&config_tree, "DecrementTTL"), &decrement_ttl);
 445
 446         char *bmode = NULL;
 447
 448         if(get_config_string(lookup_config(&config_tree, "Broadcast"), &bmode)) {
 449                 if(!strcasecmp(bmode, "no")) {
 450                         broadcast_mode = BMODE_NONE;
 451                 } else if(!strcasecmp(bmode, "yes") || !strcasecmp(bmode, "mst")) {
 452                         broadcast_mode = BMODE_MST;
 453                 } else if(!strcasecmp(bmode, "direct")) {
 454                         broadcast_mode = BMODE_DIRECT;
 455                 } else {
 456                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid broadcast mode!");
 457                         free(bmode);
 458                         return false;
 459                 }
 460
 461                 free(bmode);
 462         }
 463
 464         /* Delete all broadcast subnets before re-adding them */
 465
 466         for splay_each(subnet_t, s, &subnet_tree) {
 467                 if(!s->owner) {
 468                         splay_delete_node(&subnet_tree, node);
 469                 }
 470         }
 471
 472         const char *const DEFAULT_BROADCAST_SUBNETS[] = { "ff:ff:ff:ff:ff:ff", "255.255.255.255", "224.0.0.0/4", "ff00::/8" };
 473
 474         for(size_t i = 0; i < sizeof(DEFAULT_BROADCAST_SUBNETS) / sizeof(*DEFAULT_BROADCAST_SUBNETS); i++) {
 475                 subnet_t *s = new_subnet();
 476
 477                 if(!str2net(s, DEFAULT_BROADCAST_SUBNETS[i])) {
 478                         abort();
 479                 }
 480
 481                 subnet_add(NULL, s);
 482         }
 483
 484         for(config_t *cfg = lookup_config(&config_tree, "BroadcastSubnet"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 485                 subnet_t *s;
 486
 487                 if(!get_config_subnet(cfg, &s)) {
 488                         continue;
 489                 }
 490
 491                 subnet_add(NULL, s);
 492         }
 493
 494 #if !defined(IP_TOS)
 495
 496         if(priorityinheritance) {
 497                 logger(DEBUG_ALWAYS, LOG_WARNING, "%s not supported on this platform for IPv4 connections", "PriorityInheritance");
 498         }
 499
 500 #endif
 501
 502 #if !defined(IPV6_TCLASS)
 503
 504         if(priorityinheritance) {
 505                 logger(DEBUG_ALWAYS, LOG_WARNING, "%s not supported on this platform for IPv6 connections", "PriorityInheritance");
 506         }
 507
 508 #endif
 509
 510         if(!get_config_int(lookup_config(&config_tree, "MACExpire"), &macexpire)) {
 511                 macexpire = 600;
 512         }
 513
 514         if(get_config_int(lookup_config(&config_tree, "MaxTimeout"), &maxtimeout)) {
 515                 if(maxtimeout <= 0) {
 516                         logger(DEBUG_ALWAYS, LOG_ERR, "Bogus maximum timeout!");
 517                         return false;
 518                 }
 519         } else {
 520                 maxtimeout = 900;
 521         }
 522
 523         char *afname = NULL;
 524
 525         if(get_config_string(lookup_config(&config_tree, "AddressFamily"), &afname)) {
 526                 if(!strcasecmp(afname, "IPv4")) {
 527                         addressfamily = AF_INET;
 528                 } else if(!strcasecmp(afname, "IPv6")) {
 529                         addressfamily = AF_INET6;
 530                 } else if(!strcasecmp(afname, "any")) {
 531                         addressfamily = AF_UNSPEC;
 532                 } else {
 533                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid address family!");
 534                         free(afname);
 535                         return false;
 536                 }
 537
 538                 free(afname);
 539         }
 540
 541         get_config_bool(lookup_config(&config_tree, "Hostnames"), &hostnames);
 542
 543         if(!get_config_int(lookup_config(&config_tree, "KeyExpire"), &keylifetime)) {
 544                 keylifetime = 3600;
 545         }
 546
 547         if(!get_config_bool(lookup_config(&config_tree, "AutoConnect"), &autoconnect)) {
 548                 autoconnect = true;
 549         }
 550
 551         get_config_bool(lookup_config(&config_tree, "DisableBuggyPeers"), &disablebuggypeers);
 552
 553         if(!get_config_int(lookup_config(&config_tree, "InvitationExpire"), &invitation_lifetime)) {
 554                 invitation_lifetime = 604800;        // 1 week
 555         }
 556
 557         read_invitation_key();
 558
 559         return true;
 560 }
 561
 562 // Get the port that `from_fd` is listening on, and assign it to
 563 // `sa` if `sa` has a dynamically allocated (zero) port.
 564 static bool assign_static_port(sockaddr_t *sa, int from_fd) {
 565         // We cannot get a port from a bad FD. Bail out.
 566         if(from_fd <= 0) {
 567                 return false;
 568         }
 569
 570         int port = get_bound_port(from_fd);
 571
 572         if(!port) {
 573                 return false;
 574         }
 575
 576         // If the port is non-zero, don't reassign it as it's already static.
 577         switch(sa->sa.sa_family) {
 578         case AF_INET:
 579                 if(!sa->in.sin_port) {
 580                         sa->in.sin_port = htons(port);
 581                 }
 582
 583                 return true;
 584
 585         case AF_INET6:
 586                 if(!sa->in6.sin6_port) {
 587                         sa->in6.sin6_port = htons(port);
 588                 }
 589
 590                 return true;
 591
 592         default:
 593                 logger(DEBUG_ALWAYS, LOG_ERR, "Unknown address family 0x%x", sa->sa.sa_family);
 594                 return false;
 595         }
 596 }
 597
 598 typedef int (*bind_fn_t)(const sockaddr_t *);
 599
 600 static int bind_reusing_port(const sockaddr_t *sa, int from_fd, bind_fn_t setup) {
 601         sockaddr_t reuse_sa;
 602         memcpy(&reuse_sa, sa, SALEN(sa->sa));
 603
 604         int fd = -1;
 605
 606         // Check if the address we've been passed here is using port 0.
 607         // If it is, try to get an actual port from an already bound socket, and reuse it here.
 608         if(assign_static_port(&reuse_sa, from_fd)) {
 609                 fd = setup(&reuse_sa);
 610         }
 611
 612         // If we're binding to a hardcoded non-zero port, or no socket is listening yet,
 613         // or binding failed, try the original address.
 614         if(fd < 0) {
 615                 fd = setup(sa);
 616         }
 617
 618         return fd;
 619 }
 620
 621 /*
 622   Add listening sockets.
 623 */
 624 static bool add_listen_address(char *address, bool bindto) {
 625         char *port = myport.tcp;
 626
 627         if(address) {
 628                 char *space = strchr(address, ' ');
 629
 630                 if(space) {
 631                         *space++ = 0;
 632                         port = space;
 633                 }
 634
 635                 if(!strcmp(address, "*")) {
 636                         *address = 0;
 637                 }
 638         }
 639
 640         struct addrinfo *ai, hint = {0};
 641
 642         hint.ai_family = addressfamily;
 643
 644         hint.ai_socktype = SOCK_STREAM;
 645
 646         hint.ai_protocol = IPPROTO_TCP;
 647
 648         hint.ai_flags = AI_PASSIVE;
 649
 650 #if HAVE_DECL_RES_INIT
 651         res_init();
 652
 653 #endif
 654         int err = getaddrinfo(address && *address ? address : NULL, port, &hint, &ai);
 655
 656         free(address);
 657
 658         if(err || !ai) {
 659                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "getaddrinfo", err == EAI_SYSTEM ? strerror(err) : gai_strerror(err));
 660                 return false;
 661         }
 662
 663         for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
 664                 // Ignore duplicate addresses
 665                 bool found = false;
 666
 667                 for(int i = 0; i < listen_sockets; i++)
 668                         if(!memcmp(&listen_socket[i].sa, aip->ai_addr, aip->ai_addrlen)) {
 669                                 found = true;
 670                                 break;
 671                         }
 672
 673                 if(found) {
 674                         continue;
 675                 }
 676
 677                 if(listen_sockets >= MAXSOCKETS) {
 678                         logger(DEBUG_ALWAYS, LOG_ERR, "Too many listening sockets");
 679                         freeaddrinfo(ai);
 680                         return false;
 681                 }
 682
 683                 const sockaddr_t *sa = (sockaddr_t *) aip->ai_addr;
 684                 int from_fd = listen_socket[0].tcp.fd;
 685
 686                 // If we're binding to a dynamically allocated (zero) port, try to get the actual
 687                 // port of the first TCP socket, and use it for this one. If that succeeds, our
 688                 // tincd instance will use the same port for all addresses it listens on.
 689                 int tcp_fd = bind_reusing_port(sa, from_fd, setup_listen_socket);
 690
 691                 if(tcp_fd < 0) {
 692                         continue;
 693                 }
 694
 695                 // If we just successfully bound the first socket, use it for the UDP procedure below.
 696                 // Otherwise, keep using the socket we've obtained from listen_socket[0].
 697                 if(!from_fd) {
 698                         from_fd = tcp_fd;
 699                 }
 700
 701                 int udp_fd = bind_reusing_port(sa, from_fd, setup_vpn_in_socket);
 702
 703                 if(udp_fd < 0) {
 704                         closesocket(tcp_fd);
 705                         continue;
 706                 }
 707
 708                 listen_socket_t *sock = &listen_socket[listen_sockets];
 709                 io_add(&sock->tcp, handle_new_meta_connection, sock, tcp_fd, IO_READ);
 710                 io_add(&sock->udp, handle_incoming_vpn_data, sock, udp_fd, IO_READ);
 711
 712                 if(debug_level >= DEBUG_CONNECTIONS) {
 713                         int tcp_port = get_bound_port(tcp_fd);
 714                         char *hostname = NULL;
 715                         sockaddr2str(sa, &hostname, NULL);
 716                         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Listening on %s port %d", hostname, tcp_port);
 717                         free(hostname);
 718                 }
 719
 720                 sock->bindto = bindto;
 721                 memcpy(&sock->sa, aip->ai_addr, aip->ai_addrlen);
 722                 listen_sockets++;
 723         }
 724
 725         freeaddrinfo(ai);
 726         return true;
 727 }
 728
 729 void device_enable(void) {
 730         if(devops.enable) {
 731                 devops.enable();
 732         }
 733
 734         /* Run tinc-up script to further initialize the tap interface */
 735
 736         environment_t env;
 737         environment_init(&env);
 738         execute_script("tinc-up", &env);
 739         environment_exit(&env);
 740 }
 741
 742 void device_disable(void) {
 743         environment_t env;
 744         environment_init(&env);
 745         execute_script("tinc-down", &env);
 746         environment_exit(&env);
 747
 748         if(devops.disable) {
 749                 devops.disable();
 750         }
 751 }
 752
 753 /*
 754   Configure node_t myself and set up the local sockets (listen only)
 755 */
 756 static bool setup_myself(void) {
 757         char *name, *type;
 758         char *address = NULL;
 759         bool port_specified = false;
 760
 761         if(!(name = get_name())) {
 762                 logger(DEBUG_ALWAYS, LOG_ERR, "Name for tinc daemon required!");
 763                 return false;
 764         }
 765
 766         myname = xstrdup(name);
 767         myself = new_node();
 768         myself->connection = new_connection();
 769         myself->name = name;
 770         myself->connection->name = xstrdup(name);
 771         read_host_config(&config_tree, name, true);
 772
 773         if(!get_config_string(lookup_config(&config_tree, "Port"), &myport.tcp)) {
 774                 myport.tcp = xstrdup("655");
 775         } else {
 776                 port_specified = true;
 777         }
 778
 779         myport.udp = xstrdup(myport.tcp);
 780
 781         myself->connection->options = 0;
 782         myself->connection->protocol_major = PROT_MAJOR;
 783         myself->connection->protocol_minor = PROT_MINOR;
 784
 785         myself->options |= PROT_MINOR << 24;
 786
 787 #ifdef DISABLE_LEGACY
 788         myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
 789         experimental = myself->connection->ecdsa != NULL;
 790
 791         if(!experimental) {
 792                 logger(DEBUG_ALWAYS, LOG_ERR, "No private key available, cannot start tinc!");
 793                 return false;
 794         }
 795
 796 #else
 797
 798         if(!get_config_bool(lookup_config(&config_tree, "ExperimentalProtocol"), &experimental)) {
 799                 myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
 800                 experimental = myself->connection->ecdsa != NULL;
 801
 802                 if(!experimental) {
 803                         logger(DEBUG_ALWAYS, LOG_WARNING, "Support for SPTPS disabled.");
 804                 }
 805         } else {
 806                 if(experimental) {
 807                         myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
 808
 809                         if(!myself->connection->ecdsa) {
 810                                 return false;
 811                         }
 812                 }
 813         }
 814
 815         rsa_t *rsa = read_rsa_private_key(&config_tree, NULL);
 816
 817         if(rsa) {
 818                 myself->connection->legacy = new_legacy_ctx(rsa);
 819         } else {
 820                 if(experimental) {
 821                         logger(DEBUG_ALWAYS, LOG_WARNING, "Support for legacy protocol disabled.");
 822                 } else {
 823                         logger(DEBUG_ALWAYS, LOG_ERR, "No private keys available, cannot start tinc!");
 824                         return false;
 825                 }
 826         }
 827
 828 #endif
 829
 830         /* Ensure myport is numeric */
 831         if(!is_decimal(myport.tcp)) {
 832                 uint16_t port = service_to_port(myport.tcp);
 833
 834                 if(!port) {
 835                         return false;
 836                 }
 837
 838                 free(myport.tcp);
 839                 myport.tcp = int_to_str(port);
 840
 841                 free(myport.udp);
 842                 myport.udp = xstrdup(myport.tcp);
 843         }
 844
 845         /* Read in all the subnets specified in the host configuration file */
 846
 847         for(config_t *cfg = lookup_config(&config_tree, "Subnet"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 848                 subnet_t *subnet;
 849
 850                 if(!get_config_subnet(cfg, &subnet)) {
 851                         return false;
 852                 }
 853
 854                 subnet_add(myself, subnet);
 855         }
 856
 857         /* Check some options */
 858
 859         if(!setup_myself_reloadable()) {
 860                 return false;
 861         }
 862
 863         get_config_bool(lookup_config(&config_tree, "StrictSubnets"), &strictsubnets);
 864         get_config_bool(lookup_config(&config_tree, "TunnelServer"), &tunnelserver);
 865         strictsubnets |= tunnelserver;
 866
 867         if(get_config_int(lookup_config(&config_tree, "MaxConnectionBurst"), &max_connection_burst)) {
 868                 if(max_connection_burst <= 0) {
 869                         logger(DEBUG_ALWAYS, LOG_ERR, "MaxConnectionBurst cannot be negative!");
 870                         return false;
 871                 }
 872         }
 873
 874         if(get_config_int(lookup_config(&config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 875                 if(udp_rcvbuf < 0) {
 876                         logger(DEBUG_ALWAYS, LOG_ERR, "UDPRcvBuf cannot be negative!");
 877                         return false;
 878                 }
 879
 880                 udp_rcvbuf_warnings = true;
 881         }
 882
 883         if(get_config_int(lookup_config(&config_tree, "UDPSndBuf"), &udp_sndbuf)) {
 884                 if(udp_sndbuf < 0) {
 885                         logger(DEBUG_ALWAYS, LOG_ERR, "UDPSndBuf cannot be negative!");
 886                         return false;
 887                 }
 888
 889                 udp_sndbuf_warnings = true;
 890         }
 891
 892         get_config_int(lookup_config(&config_tree, "FWMark"), &fwmark);
 893 #ifndef SO_MARK
 894
 895         if(fwmark) {
 896                 logger(DEBUG_ALWAYS, LOG_ERR, "FWMark not supported on this platform!");
 897                 return false;
 898         }
 899
 900 #endif
 901
 902         int replaywin_int;
 903
 904         if(get_config_int(lookup_config(&config_tree, "ReplayWindow"), &replaywin_int)) {
 905                 if(replaywin_int < 0) {
 906                         logger(DEBUG_ALWAYS, LOG_ERR, "ReplayWindow cannot be negative!");
 907                         return false;
 908                 }
 909
 910                 replaywin = (unsigned)replaywin_int;
 911                 sptps_replaywin = replaywin;
 912         }
 913
 914 #ifndef DISABLE_LEGACY
 915         /* Generate packet encryption key */
 916
 917         char *cipher;
 918
 919         if(!get_config_string(lookup_config(&config_tree, "Cipher"), &cipher)) {
 920                 cipher = xstrdup("aes-256-cbc");
 921         }
 922
 923         if(!strcasecmp(cipher, "none")) {
 924                 myself->incipher = NULL;
 925         } else {
 926                 myself->incipher = cipher_alloc();
 927
 928                 if(!cipher_open_by_name(myself->incipher, cipher)) {
 929                         logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized cipher type!");
 930                         cipher_free(myself->incipher);
 931                         myself->incipher = NULL;
 932                         free(cipher);
 933                         return false;
 934                 }
 935         }
 936
 937         free(cipher);
 938
 939         timeout_add(&keyexpire_timeout, keyexpire_handler, &keyexpire_timeout, &(struct timeval) {
 940                 keylifetime, jitter()
 941         });
 942
 943         /* Check if we want to use message authentication codes... */
 944
 945         int maclength = 4;
 946         get_config_int(lookup_config(&config_tree, "MACLength"), &maclength);
 947
 948         if(maclength < 0) {
 949                 logger(DEBUG_ALWAYS, LOG_ERR, "Bogus MAC length!");
 950                 return false;
 951         }
 952
 953         char *digest;
 954
 955         if(!get_config_string(lookup_config(&config_tree, "Digest"), &digest)) {
 956                 digest = xstrdup("sha256");
 957         }
 958
 959         if(!strcasecmp(digest, "none")) {
 960                 myself->indigest = NULL;
 961         } else {
 962                 myself->indigest = digest_alloc();
 963
 964                 if(!digest_open_by_name(myself->indigest, digest, maclength)) {
 965                         logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized digest type!");
 966                         digest_free(myself->indigest);
 967                         myself->indigest = NULL;
 968                         free(digest);
 969                         return false;
 970                 }
 971         }
 972
 973         free(digest);
 974 #endif
 975
 976         /* Compression */
 977         int incompression = 0;
 978
 979         if(get_config_int(lookup_config(&config_tree, "Compression"), &incompression)) {
 980                 myself->incompression = incompression;
 981
 982                 switch(myself->incompression) {
 983                 case COMPRESS_LZ4:
 984 #ifdef HAVE_LZ4
 985                         break;
 986 #else
 987                         logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
 988                         logger(DEBUG_ALWAYS, LOG_ERR, "LZ4 compression is unavailable on this node.");
 989                         return false;
 990 #endif
 991
 992                 case COMPRESS_LZO_HI:
 993                 case COMPRESS_LZO_LO:
 994 #ifdef HAVE_LZO
 995                         break;
 996 #else
 997                         logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
 998                         logger(DEBUG_ALWAYS, LOG_ERR, "LZO compression is unavailable on this node.");
 999                         return false;
1000 #endif
1001
1002                 case COMPRESS_ZLIB_9:
1003                 case COMPRESS_ZLIB_8:
1004                 case COMPRESS_ZLIB_7:
1005                 case COMPRESS_ZLIB_6:
1006                 case COMPRESS_ZLIB_5:
1007                 case COMPRESS_ZLIB_4:
1008                 case COMPRESS_ZLIB_3:
1009                 case COMPRESS_ZLIB_2:
1010                 case COMPRESS_ZLIB_1:
1011 #ifdef HAVE_ZLIB
1012                         break;
1013 #else
1014                         logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
1015                         logger(DEBUG_ALWAYS, LOG_ERR, "ZLIB compression is unavailable on this node.");
1016                         return false;
1017 #endif
1018
1019                 case COMPRESS_NONE:
1020                         break;
1021
1022                 default:
1023                         logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
1024                         logger(DEBUG_ALWAYS, LOG_ERR, "Compression level %i is unrecognized by this node.", myself->incompression);
1025                         return false;
1026                 }
1027         } else {
1028                 myself->incompression = COMPRESS_NONE;
1029         }
1030
1031         /* Done */
1032
1033         myself->nexthop = myself;
1034         myself->via = myself;
1035         myself->status.reachable = true;
1036         myself->last_state_change = now.tv_sec;
1037         myself->status.sptps = experimental;
1038         node_add(myself);
1039
1040         graph();
1041
1042         load_all_nodes();
1043
1044         /* Open device */
1045
1046         devops = os_devops;
1047
1048         if(get_config_string(lookup_config(&config_tree, "DeviceType"), &type)) {
1049                 if(!strcasecmp(type, DEVICE_DUMMY)) {
1050                         devops = dummy_devops;
1051                 } else if(!strcasecmp(type, "raw_socket")) {
1052                         devops = raw_socket_devops;
1053                 } else if(!strcasecmp(type, "multicast")) {
1054                         devops = multicast_devops;
1055                 }
1056
1057 #ifdef HAVE_SYS_UN_H
1058                 else if(!strcasecmp(type, "fd")) {
1059                         devops = fd_devops;
1060                 }
1061
1062 #endif
1063 #ifdef ENABLE_UML
1064                 else if(!strcasecmp(type, "uml")) {
1065                         devops = uml_devops;
1066                 }
1067
1068 #endif
1069 #ifdef ENABLE_VDE
1070                 else if(!strcasecmp(type, "vde")) {
1071                         devops = vde_devops;
1072                 }
1073
1074 #endif
1075                 free(type);
1076         }
1077
1078         get_config_bool(lookup_config(&config_tree, "DeviceStandby"), &device_standby);
1079
1080         if(!devops.setup()) {
1081                 return false;
1082         }
1083
1084         if(device_fd >= 0) {
1085                 io_add(&device_io, handle_device_data, NULL, device_fd, IO_READ);
1086         }
1087
1088         /* Open sockets */
1089
1090         if(!do_detach && getenv("LISTEN_FDS")) {
1091                 sockaddr_t sa;
1092                 socklen_t salen;
1093
1094                 listen_sockets = atoi(getenv("LISTEN_FDS"));
1095 #ifdef HAVE_UNSETENV
1096                 unsetenv("LISTEN_FDS");
1097 #endif
1098
1099                 if(listen_sockets > MAXSOCKETS) {
1100                         logger(DEBUG_ALWAYS, LOG_ERR, "Too many listening sockets");
1101                         return false;
1102                 }
1103
1104                 for(int i = 0; i < listen_sockets; i++) {
1105                         const int tcp_fd = i + 3;
1106                         salen = sizeof(sa);
1107
1108                         if(getsockname(tcp_fd, &sa.sa, &salen) < 0) {
1109                                 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get address of listen fd %d: %s", tcp_fd, sockstrerror(sockerrno));
1110                                 return false;
1111                         }
1112
1113 #ifdef FD_CLOEXEC
1114                         fcntl(tcp_fd, F_SETFD, FD_CLOEXEC);
1115 #endif
1116
1117                         int udp_fd = setup_vpn_in_socket(&sa);
1118
1119                         if(udp_fd < 0) {
1120                                 return false;
1121                         }
1122
1123                         io_add(&listen_socket[i].tcp, (io_cb_t)handle_new_meta_connection, &listen_socket[i], tcp_fd, IO_READ);
1124                         io_add(&listen_socket[i].udp, (io_cb_t)handle_incoming_vpn_data, &listen_socket[i], udp_fd, IO_READ);
1125
1126                         if(debug_level >= DEBUG_CONNECTIONS) {
1127                                 char *hostname = sockaddr2hostname(&sa);
1128                                 logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Listening on %s", hostname);
1129                                 free(hostname);
1130                         }
1131
1132                         memcpy(&listen_socket[i].sa, &sa, salen);
1133                 }
1134         } else {
1135                 listen_sockets = 0;
1136                 int cfgs = 0;
1137
1138                 for(config_t *cfg = lookup_config(&config_tree, "BindToAddress"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
1139                         cfgs++;
1140                         get_config_string(cfg, &address);
1141
1142                         if(!add_listen_address(address, true)) {
1143                                 return false;
1144                         }
1145                 }
1146
1147                 for(config_t *cfg = lookup_config(&config_tree, "ListenAddress"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
1148                         cfgs++;
1149                         get_config_string(cfg, &address);
1150
1151                         if(!add_listen_address(address, false)) {
1152                                 return false;
1153                         }
1154                 }
1155
1156                 if(!cfgs)
1157                         if(!add_listen_address(address, NULL)) {
1158                                 return false;
1159                         }
1160         }
1161
1162         if(!listen_sockets) {
1163                 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to create any listening socket!");
1164                 return false;
1165         }
1166
1167         /* If no Port option was specified, set myport to the port used by the first listening socket. */
1168
1169         if(!port_specified || atoi(myport.tcp) == 0) {
1170                 listen_socket_t *sock = &listen_socket[0];
1171
1172                 uint16_t tcp = get_bound_port(sock->tcp.fd);
1173                 free(myport.tcp);
1174                 myport.tcp = int_to_str(tcp);
1175
1176                 uint16_t udp = get_bound_port(sock->udp.fd);
1177                 free(myport.udp);
1178                 myport.udp = int_to_str(udp);
1179         }
1180
1181         xasprintf(&myself->hostname, "MYSELF port %s", myport.tcp);
1182         myself->connection->hostname = xstrdup(myself->hostname);
1183
1184         char *upnp = NULL;
1185         get_config_string(lookup_config(&config_tree, "UPnP"), &upnp);
1186         bool upnp_tcp = false;
1187         bool upnp_udp = false;
1188
1189         if(upnp) {
1190                 if(!strcasecmp(upnp, "yes")) {
1191                         upnp_tcp = upnp_udp = true;
1192                 } else if(!strcasecmp(upnp, "udponly")) {
1193                         upnp_udp = true;
1194                 }
1195
1196                 free(upnp);
1197         }
1198
1199         if(upnp_tcp || upnp_udp) {
1200 #ifdef HAVE_MINIUPNPC
1201                 upnp_init(upnp_tcp, upnp_udp);
1202 #else
1203                 logger(DEBUG_ALWAYS, LOG_WARNING, "UPnP was requested, but tinc isn't built with miniupnpc support!");
1204 #endif
1205         }
1206
1207         /* Done. */
1208
1209         last_config_check = now.tv_sec;
1210
1211         return true;
1212 }
1213
1214 /*
1215   initialize network
1216 */
1217 bool setup_network(void) {
1218         init_connections();
1219         init_subnets();
1220
1221         if(get_config_int(lookup_config(&config_tree, "PingInterval"), &pinginterval)) {
1222                 if(pinginterval < 1) {
1223                         pinginterval = 86400;
1224                 }
1225         } else {
1226                 pinginterval = 60;
1227         }
1228
1229         if(!get_config_int(lookup_config(&config_tree, "PingTimeout"), &pingtimeout)) {
1230                 pingtimeout = 5;
1231         }
1232
1233         if(pingtimeout < 1 || pingtimeout > pinginterval) {
1234                 pingtimeout = pinginterval;
1235         }
1236
1237         if(!get_config_int(lookup_config(&config_tree, "MaxOutputBufferSize"), &maxoutbufsize)) {
1238                 maxoutbufsize = 10 * MTU;
1239         }
1240
1241         if(!setup_myself()) {
1242                 return false;
1243         }
1244
1245         if(!init_control()) {
1246                 return false;
1247         }
1248
1249         if(!device_standby) {
1250                 device_enable();
1251         }
1252
1253         /* Run subnet-up scripts for our own subnets */
1254
1255         subnet_update(myself, NULL, true);
1256
1257         return true;
1258 }
1259
1260 /*
1261   close all open network connections
1262 */
1263 void close_network_connections(void) {
1264         for(list_node_t *node = connection_list.head, *next; node; node = next) {
1265                 next = node->next;
1266                 connection_t *c = node->data;
1267
1268                 /* Keep control connections open until the end, so they know when we really terminated */
1269                 if(c->status.control) {
1270                         c->socket = -1;
1271                 }
1272
1273                 c->outgoing = NULL;
1274                 terminate_connection(c, false);
1275         }
1276
1277         list_empty_list(&outgoing_list);
1278
1279         if(myself && myself->connection) {
1280                 subnet_update(myself, NULL, false);
1281                 free_connection(myself->connection);
1282         }
1283
1284         for(int i = 0; i < listen_sockets; i++) {
1285                 io_del(&listen_socket[i].tcp);
1286                 io_del(&listen_socket[i].udp);
1287                 closesocket(listen_socket[i].tcp.fd);
1288                 closesocket(listen_socket[i].udp.fd);
1289         }
1290
1291         exit_requests();
1292         exit_edges();
1293         exit_subnets();
1294         exit_nodes();
1295         exit_connections();
1296
1297         if(!device_standby) {
1298                 device_disable();
1299         }
1300
1301         free(myport.tcp);
1302         free(myport.udp);
1303
1304         if(device_fd >= 0) {
1305                 io_del(&device_io);
1306         }
1307
1308         if(devops.close) {
1309                 devops.close();
1310         }
1311
1312         exit_control();
1313
1314         free(scriptextension);
1315         free(scriptinterpreter);
1316
1317         return;
1318 }