src/tincd.c

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