tinc-vpn.org Git - tinc/blob - src/tincd.c

   1 /*
   2     tincd.c -- the main file for tincd
   3     Copyright (C) 1998-2005 Ivo Timmermans
   4                   2000-2013 Guus Sliepen <guus@tinc-vpn.org>
   5                   2008      Max Rijevski <maksuf@gmail.com>
   6                   2009      Michael Tokarev <mjt@tls.msk.ru>
   7                   2010      Julien Muchembled <jm@jmuchemb.eu>
   8                   2010      Timothy Redaelli <timothy@redaelli.eu>
   9
  10     This program is free software; you can redistribute it and/or modify
  11     it under the terms of the GNU General Public License as published by
  12     the Free Software Foundation; either version 2 of the License, or
  13     (at your option) any later version.
  14
  15     This program is distributed in the hope that it will be useful,
  16     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18     GNU General Public License for more details.
  19
  20     You should have received a copy of the GNU General Public License along
  21     with this program; if not, write to the Free Software Foundation, Inc.,
  22     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  23 */
  24
  25 #include "system.h"
  26
  27 /* Darwin (MacOS/X) needs the following definition... */
  28 #ifndef _P1003_1B_VISIBLE
  29 #define _P1003_1B_VISIBLE
  30 #endif
  31
  32 #ifdef HAVE_SYS_MMAN_H
  33 #include <sys/mman.h>
  34 #endif
  35
  36 #include <openssl/rand.h>
  37 #include <openssl/rsa.h>
  38 #include <openssl/pem.h>
  39 #include <openssl/evp.h>
  40 #include <openssl/engine.h>
  41
  42 #ifdef HAVE_LZO
  43 #include LZO1X_H
  44 #endif
  45
  46 #ifndef HAVE_MINGW
  47 #include <pwd.h>
  48 #include <grp.h>
  49 #include <time.h>
  50 #endif
  51
  52 #include <getopt.h>
  53 #include "pidfile.h"
  54
  55 #include "conf.h"
  56 #include "device.h"
  57 #include "logger.h"
  58 #include "net.h"
  59 #include "netutl.h"
  60 #include "process.h"
  61 #include "protocol.h"
  62 #include "utils.h"
  63 #include "xalloc.h"
  64
  65 /* The name this program was run with. */
  66 char *program_name = NULL;
  67
  68 /* If nonzero, display usage information and exit. */
  69 bool show_help = false;
  70
  71 /* If nonzero, print the version on standard output and exit.  */
  72 bool show_version = false;
  73
  74 /* If nonzero, it will attempt to kill a running tincd and exit. */
  75 int kill_tincd = 0;
  76
  77 /* If nonzero, generate public/private keypair for this host/net. */
  78 int generate_keys = 0;
  79
  80 /* If nonzero, use null ciphers and skip all key exchanges. */
  81 bool bypass_security = false;
  82
  83 /* If nonzero, disable swapping for this process. */
  84 bool do_mlock = false;
  85
  86 /* If nonzero, chroot to netdir after startup. */
  87 static bool do_chroot = false;
  88
  89 /* If !NULL, do setuid to given user after startup */
  90 static const char *switchuser = NULL;
  91
  92 /* If nonzero, write log entries to a separate file. */
  93 bool use_logfile = false;
  94
  95 char *identname = NULL;                         /* program name for syslog */
  96 char *pidfilename = NULL;                       /* pid file location */
  97 char *logfilename = NULL;                       /* log file location */
  98 char **g_argv;                                  /* a copy of the cmdline arguments */
  99
 100 static int status;
 101
 102 static struct option const long_options[] = {
 103         {"config", required_argument, NULL, 'c'},
 104         {"kill", optional_argument, NULL, 'k'},
 105         {"net", required_argument, NULL, 'n'},
 106         {"help", no_argument, NULL, 1},
 107         {"version", no_argument, NULL, 2},
 108         {"no-detach", no_argument, NULL, 'D'},
 109         {"generate-keys", optional_argument, NULL, 'K'},
 110         {"debug", optional_argument, NULL, 'd'},
 111         {"bypass-security", no_argument, NULL, 3},
 112         {"mlock", no_argument, NULL, 'L'},
 113         {"chroot", no_argument, NULL, 'R'},
 114         {"user", required_argument, NULL, 'U'},
 115         {"logfile", optional_argument, NULL, 4},
 116         {"pidfile", required_argument, NULL, 5},
 117         {"option", required_argument, NULL, 'o'},
 118         {NULL, 0, NULL, 0}
 119 };
 120
 121 #ifdef HAVE_MINGW
 122 static struct WSAData wsa_state;
 123 CRITICAL_SECTION mutex;
 124 int main2(int argc, char **argv);
 125 #endif
 126
 127 static void usage(bool status) {
 128         if(status)
 129                 fprintf(stderr, "Try `%s --help\' for more information.\n",
 130                                 program_name);
 131         else {
 132                 printf("Usage: %s [option]...\n\n", program_name);
 133                 printf("  -c, --config=DIR               Read configuration options from DIR.\n"
 134                                 "  -D, --no-detach                Don't fork and detach.\n"
 135                                 "  -d, --debug[=LEVEL]            Increase debug level or set it to LEVEL.\n"
 136                                 "  -k, --kill[=SIGNAL]            Attempt to kill a running tincd and exit.\n"
 137                                 "  -n, --net=NETNAME              Connect to net NETNAME.\n"
 138                                 "  -K, --generate-keys[=BITS]     Generate public/private RSA keypair.\n"
 139                                 "  -L, --mlock                    Lock tinc into main memory.\n"
 140                                 "      --logfile[=FILENAME]       Write log entries to a logfile.\n"
 141                                 "      --pidfile=FILENAME         Write PID to FILENAME.\n"
 142                                 "  -o, --option=[HOST.]KEY=VALUE  Set global/host configuration value.\n"
 143                                 "  -R, --chroot                   chroot to NET dir at startup.\n"
 144                                 "  -U, --user=USER                setuid to given USER at startup.\n"
 145                                 "      --help                     Display this help and exit.\n"
 146                                 "      --version                  Output version information and exit.\n\n");
 147                 printf("Report bugs to tinc@tinc-vpn.org.\n");
 148         }
 149 }
 150
 151 static bool parse_options(int argc, char **argv) {
 152         config_t *cfg;
 153         int r;
 154         int option_index = 0;
 155         int lineno = 0;
 156
 157         cmdline_conf = list_alloc((list_action_t)free_config);
 158
 159         while((r = getopt_long(argc, argv, "c:DLd::k::n:o:K::RU:", long_options, &option_index)) != EOF) {
 160                 switch (r) {
 161                         case 0:                         /* long option */
 162                                 break;
 163
 164                         case 'c':                               /* config file */
 165                                 confbase = xstrdup(optarg);
 166                                 break;
 167
 168                         case 'D':                               /* no detach */
 169                                 do_detach = false;
 170                                 break;
 171
 172                         case 'L':                               /* no detach */
 173 #ifndef HAVE_MLOCKALL
 174                                 logger(LOG_ERR, "%s not supported on this platform", "mlockall()");
 175                                 return false;
 176 #else
 177                                 do_mlock = true;
 178                                 break;
 179 #endif
 180
 181                         case 'd':                               /* increase debug level */
 182                                 if(!optarg && optind < argc && *argv[optind] != '-')
 183                                         optarg = argv[optind++];
 184                                 if(optarg)
 185                                         debug_level = atoi(optarg);
 186                                 else
 187                                         debug_level++;
 188                                 break;
 189
 190                         case 'k':                               /* kill old tincds */
 191 #ifndef HAVE_MINGW
 192                                 if(!optarg && optind < argc && *argv[optind] != '-')
 193                                         optarg = argv[optind++];
 194                                 if(optarg) {
 195                                         if(!strcasecmp(optarg, "HUP"))
 196                                                 kill_tincd = SIGHUP;
 197                                         else if(!strcasecmp(optarg, "TERM"))
 198                                                 kill_tincd = SIGTERM;
 199                                         else if(!strcasecmp(optarg, "KILL"))
 200                                                 kill_tincd = SIGKILL;
 201                                         else if(!strcasecmp(optarg, "USR1"))
 202                                                 kill_tincd = SIGUSR1;
 203                                         else if(!strcasecmp(optarg, "USR2"))
 204                                                 kill_tincd = SIGUSR2;
 205                                         else if(!strcasecmp(optarg, "WINCH"))
 206                                                 kill_tincd = SIGWINCH;
 207                                         else if(!strcasecmp(optarg, "INT"))
 208                                                 kill_tincd = SIGINT;
 209                                         else if(!strcasecmp(optarg, "ALRM"))
 210                                                 kill_tincd = SIGALRM;
 211                                         else if(!strcasecmp(optarg, "ABRT"))
 212                                                 kill_tincd = SIGABRT;
 213                                         else {
 214                                                 kill_tincd = atoi(optarg);
 215
 216                                                 if(!kill_tincd) {
 217                                                         fprintf(stderr, "Invalid argument `%s'; SIGNAL must be a number or one of HUP, TERM, KILL, USR1, USR2, WINCH, INT or ALRM.\n",
 218                                                                         optarg);
 219                                                         usage(true);
 220                                                         return false;
 221                                                 }
 222                                         }
 223                                 } else
 224                                         kill_tincd = SIGTERM;
 225 #else
 226                                         kill_tincd = 1;
 227 #endif
 228                                 break;
 229
 230                         case 'n':                               /* net name given */
 231                                 /* netname "." is special: a "top-level name" */
 232                                 netname = strcmp(optarg, ".") != 0 ? xstrdup(optarg) : NULL;
 233                                 break;
 234
 235                         case 'o':                               /* option */
 236                                 cfg = parse_config_line(optarg, NULL, ++lineno);
 237                                 if (!cfg)
 238                                         return false;
 239                                 list_insert_tail(cmdline_conf, cfg);
 240                                 break;
 241
 242                         case 'K':                               /* generate public/private keypair */
 243                                 if(!optarg && optind < argc && *argv[optind] != '-')
 244                                         optarg = argv[optind++];
 245                                 if(optarg) {
 246                                         generate_keys = atoi(optarg);
 247
 248                                         if(generate_keys < 512) {
 249                                                 fprintf(stderr, "Invalid argument `%s'; BITS must be a number equal to or greater than 512.\n",
 250                                                                 optarg);
 251                                                 usage(true);
 252                                                 return false;
 253                                         }
 254
 255                                         generate_keys &= ~7;    /* Round it to bytes */
 256                                 } else
 257                                         generate_keys = 2048;
 258                                 break;
 259
 260                         case 'R':                               /* chroot to NETNAME dir */
 261                                 do_chroot = true;
 262                                 break;
 263
 264                         case 'U':                               /* setuid to USER */
 265                                 switchuser = optarg;
 266                                 break;
 267
 268                         case 1:                                 /* show help */
 269                                 show_help = true;
 270                                 break;
 271
 272                         case 2:                                 /* show version */
 273                                 show_version = true;
 274                                 break;
 275
 276                         case 3:                                 /* bypass security */
 277                                 bypass_security = true;
 278                                 break;
 279
 280                         case 4:                                 /* write log entries to a file */
 281                                 use_logfile = true;
 282                                 if(!optarg && optind < argc && *argv[optind] != '-')
 283                                         optarg = argv[optind++];
 284                                 if(optarg)
 285                                         logfilename = xstrdup(optarg);
 286                                 break;
 287
 288                         case 5:                                 /* write PID to a file */
 289                                 pidfilename = xstrdup(optarg);
 290                                 break;
 291
 292                         case '?':
 293                                 usage(true);
 294                                 return false;
 295
 296                         default:
 297                                 break;
 298                 }
 299         }
 300
 301         if(optind < argc) {
 302                 fprintf(stderr, "%s: unrecognized argument '%s'\n", argv[0], argv[optind]);
 303                 usage(true);
 304                 return false;
 305         }
 306
 307         return true;
 308 }
 309
 310 /* This function prettyprints the key generation process */
 311
 312 static void indicator(int a, int b, void *p) {
 313         switch (a) {
 314                 case 0:
 315                         fprintf(stderr, ".");
 316                         break;
 317
 318                 case 1:
 319                         fprintf(stderr, "+");
 320                         break;
 321
 322                 case 2:
 323                         fprintf(stderr, "-");
 324                         break;
 325
 326                 case 3:
 327                         switch (b) {
 328                                 case 0:
 329                                         fprintf(stderr, " p\n");
 330                                         break;
 331
 332                                 case 1:
 333                                         fprintf(stderr, " q\n");
 334                                         break;
 335
 336                                 default:
 337                                         fprintf(stderr, "?");
 338                         }
 339                         break;
 340
 341                 default:
 342                         fprintf(stderr, "?");
 343         }
 344 }
 345
 346 /*
 347   Generate a public/private RSA keypair, and ask for a file to store
 348   them in.
 349 */
 350 static bool keygen(int bits) {
 351         RSA *rsa_key;
 352         FILE *f;
 353         char *name = get_name();
 354         char *pubname, *privname;
 355
 356         fprintf(stderr, "Generating %d bits keys:\n", bits);
 357         rsa_key = RSA_generate_key(bits, 0x10001, indicator, NULL);
 358
 359         if(!rsa_key) {
 360                 fprintf(stderr, "Error during key generation!\n");
 361                 return false;
 362         } else
 363                 fprintf(stderr, "Done.\n");
 364
 365         xasprintf(&privname, "%s/rsa_key.priv", confbase);
 366         f = ask_and_open(privname, "private RSA key");
 367         free(privname);
 368
 369         if(!f)
 370                 return false;
 371
 372 #ifdef HAVE_FCHMOD
 373         /* Make it unreadable for others. */
 374         fchmod(fileno(f), 0600);
 375 #endif
 376
 377         fputc('\n', f);
 378         PEM_write_RSAPrivateKey(f, rsa_key, NULL, NULL, 0, NULL, NULL);
 379         fclose(f);
 380
 381         if(name)
 382                 xasprintf(&pubname, "%s/hosts/%s", confbase, name);
 383         else
 384                 xasprintf(&pubname, "%s/rsa_key.pub", confbase);
 385
 386         f = ask_and_open(pubname, "public RSA key");
 387         free(pubname);
 388
 389         if(!f)
 390                 return false;
 391
 392         fputc('\n', f);
 393         PEM_write_RSAPublicKey(f, rsa_key);
 394         fclose(f);
 395         free(name);
 396
 397         return true;
 398 }
 399
 400 /*
 401   Set all files and paths according to netname
 402 */
 403 static void make_names(void) {
 404 #ifdef HAVE_MINGW
 405         HKEY key;
 406         char installdir[1024] = "";
 407         DWORD len = sizeof(installdir);
 408 #endif
 409
 410         if(netname)
 411                 xasprintf(&identname, "tinc.%s", netname);
 412         else
 413                 identname = xstrdup("tinc");
 414
 415 #ifdef HAVE_MINGW
 416         if(!RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\tinc", 0, KEY_READ, &key)) {
 417                 if(!RegQueryValueEx(key, NULL, 0, 0, (LPBYTE)installdir, &len)) {
 418                         if(!logfilename)
 419                                 xasprintf(&logfilename, "%s/log/%s.log", identname);
 420                         if(!confbase) {
 421                                 if(netname)
 422                                         xasprintf(&confbase, "%s/%s", installdir, netname);
 423                                 else
 424                                         xasprintf(&confbase, "%s", installdir);
 425                         }
 426                 }
 427                 RegCloseKey(key);
 428                 if(*installdir)
 429                         return;
 430         }
 431 #endif
 432
 433         if(!pidfilename)
 434                 xasprintf(&pidfilename, LOCALSTATEDIR "/run/%s.pid", identname);
 435
 436         if(!logfilename)
 437                 xasprintf(&logfilename, LOCALSTATEDIR "/log/%s.log", identname);
 438
 439         if(netname) {
 440                 if(!confbase)
 441                         xasprintf(&confbase, CONFDIR "/tinc/%s", netname);
 442                 else
 443                         logger(LOG_INFO, "Both netname and configuration directory given, using the latter...");
 444         } else {
 445                 if(!confbase)
 446                         xasprintf(&confbase, CONFDIR "/tinc");
 447         }
 448 }
 449
 450 static void free_names() {
 451         if (identname) free(identname);
 452         if (netname) free(netname);
 453         if (pidfilename) free(pidfilename);
 454         if (logfilename) free(logfilename);
 455         if (confbase) free(confbase);
 456 }
 457
 458 static bool drop_privs() {
 459 #ifdef HAVE_MINGW
 460         if (switchuser) {
 461                 logger(LOG_ERR, "%s not supported on this platform", "-U");
 462                 return false;
 463         }
 464         if (do_chroot) {
 465                 logger(LOG_ERR, "%s not supported on this platform", "-R");
 466                 return false;
 467         }
 468 #else
 469         uid_t uid = 0;
 470         if (switchuser) {
 471                 struct passwd *pw = getpwnam(switchuser);
 472                 if (!pw) {
 473                         logger(LOG_ERR, "unknown user `%s'", switchuser);
 474                         return false;
 475                 }
 476                 uid = pw->pw_uid;
 477                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 478                     setgid(pw->pw_gid) != 0) {
 479                         logger(LOG_ERR, "System call `%s' failed: %s",
 480                                "initgroups", strerror(errno));
 481                         return false;
 482                 }
 483 #ifndef __ANDROID__
 484 // Not supported in android NDK
 485                 endgrent();
 486                 endpwent();
 487 #endif
 488         }
 489         if (do_chroot) {
 490                 tzset();        /* for proper timestamps in logs */
 491                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 492                         logger(LOG_ERR, "System call `%s' failed: %s",
 493                                "chroot", strerror(errno));
 494                         return false;
 495                 }
 496                 free(confbase);
 497                 confbase = xstrdup("");
 498         }
 499         if (switchuser)
 500                 if (setuid(uid) != 0) {
 501                         logger(LOG_ERR, "System call `%s' failed: %s",
 502                                "setuid", strerror(errno));
 503                         return false;
 504                 }
 505 #endif
 506         return true;
 507 }
 508
 509 #ifdef HAVE_MINGW
 510 # define setpriority(level) !SetPriorityClass(GetCurrentProcess(), (level))
 511 #else
 512 # define NORMAL_PRIORITY_CLASS 0
 513 # define BELOW_NORMAL_PRIORITY_CLASS 10
 514 # define HIGH_PRIORITY_CLASS -10
 515 # define setpriority(level) (setpriority(PRIO_PROCESS, 0, (level)))
 516 #endif
 517
 518 int main(int argc, char **argv) {
 519         program_name = argv[0];
 520
 521         if(!parse_options(argc, argv))
 522                 return 1;
 523
 524         make_names();
 525
 526         if(show_version) {
 527                 printf("%s version %s (built %s %s, protocol %d)\n", PACKAGE,
 528                            VERSION, __DATE__, __TIME__, PROT_CURRENT);
 529                 printf("Copyright (C) 1998-2013 Ivo Timmermans, Guus Sliepen and others.\n"
 530                                 "See the AUTHORS file for a complete list.\n\n"
 531                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 532                                 "and you are welcome to redistribute it under certain conditions;\n"
 533                                 "see the file COPYING for details.\n");
 534
 535                 return 0;
 536         }
 537
 538         if(show_help) {
 539                 usage(false);
 540                 return 0;
 541         }
 542
 543         if(kill_tincd)
 544                 return !kill_other(kill_tincd);
 545
 546         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 547
 548         g_argv = argv;
 549
 550         if(getenv("LISTEN_PID") && atoi(getenv("LISTEN_PID")) == getpid())
 551                 do_detach = false;
 552 #ifdef HAVE_UNSETENV
 553         unsetenv("LISTEN_PID");
 554 #endif
 555
 556         init_configuration(&config_tree);
 557
 558         /* Slllluuuuuuurrrrp! */
 559
 560         RAND_load_file("/dev/urandom", 1024);
 561
 562         ENGINE_load_builtin_engines();
 563         ENGINE_register_all_complete();
 564
 565         OpenSSL_add_all_algorithms();
 566
 567         if(generate_keys) {
 568                 read_server_config();
 569                 return !keygen(generate_keys);
 570         }
 571
 572         if(!read_server_config())
 573                 return 1;
 574
 575 #ifdef HAVE_LZO
 576         if(lzo_init() != LZO_E_OK) {
 577                 logger(LOG_ERR, "Error initializing LZO compressor!");
 578                 return 1;
 579         }
 580 #endif
 581
 582 #ifdef HAVE_MINGW
 583         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 584                 logger(LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 585                 return 1;
 586         }
 587
 588         if(!do_detach || !init_service())
 589                 return main2(argc, argv);
 590         else
 591                 return 1;
 592 }
 593
 594 int main2(int argc, char **argv) {
 595         InitializeCriticalSection(&mutex);
 596         EnterCriticalSection(&mutex);
 597 #endif
 598         char *priority = NULL;
 599
 600         if(!detach())
 601                 return 1;
 602
 603 #ifdef HAVE_MLOCKALL
 604         /* Lock all pages into memory if requested.
 605          * This has to be done after daemon()/fork() so it works for child.
 606          * No need to do that in parent as it's very short-lived. */
 607         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 608                 logger(LOG_ERR, "System call `%s' failed: %s", "mlockall",
 609                    strerror(errno));
 610                 return 1;
 611         }
 612 #endif
 613
 614         /* Setup sockets and open device. */
 615
 616         if(!setup_network())
 617                 goto end;
 618
 619         /* Initiate all outgoing connections. */
 620
 621         try_outgoing_connections();
 622
 623         /* Change process priority */
 624
 625         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 626                 if(!strcasecmp(priority, "Normal")) {
 627                         if (setpriority(NORMAL_PRIORITY_CLASS) != 0) {
 628                                 logger(LOG_ERR, "System call `%s' failed: %s",
 629                                        "setpriority", strerror(errno));
 630                                 goto end;
 631                         }
 632                 } else if(!strcasecmp(priority, "Low")) {
 633                         if (setpriority(BELOW_NORMAL_PRIORITY_CLASS) != 0) {
 634                                        logger(LOG_ERR, "System call `%s' failed: %s",
 635                                        "setpriority", strerror(errno));
 636                                 goto end;
 637                         }
 638                 } else if(!strcasecmp(priority, "High")) {
 639                         if (setpriority(HIGH_PRIORITY_CLASS) != 0) {
 640                                 logger(LOG_ERR, "System call `%s' failed: %s",
 641                                        "setpriority", strerror(errno));
 642                                 goto end;
 643                         }
 644                 } else {
 645                         logger(LOG_ERR, "Invalid priority `%s`!", priority);
 646                         goto end;
 647                 }
 648         }
 649
 650         /* drop privileges */
 651         if (!drop_privs())
 652                 goto end;
 653
 654         /* Start main loop. It only exits when tinc is killed. */
 655
 656         status = main_loop();
 657
 658         /* Shutdown properly. */
 659
 660         ifdebug(CONNECTIONS)
 661                 devops.dump_stats();
 662
 663         close_network_connections();
 664
 665 end:
 666         logger(LOG_NOTICE, "Terminating");
 667
 668 #ifndef HAVE_MINGW
 669         remove_pid(pidfilename);
 670 #endif
 671
 672         free(priority);
 673
 674         EVP_cleanup();
 675         ENGINE_cleanup();
 676         CRYPTO_cleanup_all_ex_data();
 677         ERR_remove_state(0);
 678         ERR_free_strings();
 679
 680         exit_configuration(&config_tree);
 681         list_free(cmdline_conf);
 682         free_names();
 683
 684         return status;
 685 }