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 int main2(int argc, char **argv);
 122 #endif
 123
 124 static void usage(bool status) {
 125         if(status)
 126                 fprintf(stderr, "Try `%s --help\' for more information.\n",
 127                                 program_name);
 128         else {
 129                 printf("Usage: %s [option]...\n\n", program_name);
 130                 printf("  -c, --config=DIR           Read configuration options from DIR.\n"
 131                                 "  -D, --no-detach            Don't fork and detach.\n"
 132                                 "  -d, --debug[=LEVEL]        Increase debug level or set it to LEVEL.\n"
 133                                 "  -k, --kill[=SIGNAL]        Attempt to kill a running tincd and exit.\n"
 134                                 "  -n, --net=NETNAME          Connect to net NETNAME.\n"
 135                                 "  -K, --generate-keys[=BITS] Generate public/private RSA keypair.\n"
 136                                 "  -L, --mlock                Lock tinc into main memory.\n"
 137                                 "      --logfile[=FILENAME]   Write log entries to a logfile.\n"
 138                                 "      --pidfile=FILENAME     Write PID to FILENAME.\n"
 139                                 "  -R, --chroot               chroot to NET dir at startup.\n"
 140                                 "  -U, --user=USER            setuid to given USER at startup.\n"
 141                                 "      --help                 Display this help and exit.\n"
 142                                 "      --version              Output version information and exit.\n\n");
 143                 printf("Report bugs to tinc@tinc-vpn.org.\n");
 144         }
 145 }
 146
 147 static bool parse_options(int argc, char **argv) {
 148         int r;
 149         int option_index = 0;
 150
 151         while((r = getopt_long(argc, argv, "c:DLd::k::n:K::RU:", long_options, &option_index)) != EOF) {
 152                 switch (r) {
 153                         case 0:                         /* long option */
 154                                 break;
 155
 156                         case 'c':                               /* config file */
 157                                 confbase = xstrdup(optarg);
 158                                 break;
 159
 160                         case 'D':                               /* no detach */
 161                                 do_detach = false;
 162                                 break;
 163
 164                         case 'L':                               /* no detach */
 165 #ifndef HAVE_MLOCKALL
 166                                 logger(LOG_ERR, "%s not supported on this platform", "mlockall()");
 167                                 return false;
 168 #else
 169                                 do_mlock = true;
 170                                 break;
 171 #endif
 172
 173                         case 'd':                               /* inc debug level */
 174                                 if(optarg)
 175                                         debug_level = atoi(optarg);
 176                                 else
 177                                         debug_level++;
 178                                 break;
 179
 180                         case 'k':                               /* kill old tincds */
 181 #ifndef HAVE_MINGW
 182                                 if(optarg) {
 183                                         if(!strcasecmp(optarg, "HUP"))
 184                                                 kill_tincd = SIGHUP;
 185                                         else if(!strcasecmp(optarg, "TERM"))
 186                                                 kill_tincd = SIGTERM;
 187                                         else if(!strcasecmp(optarg, "KILL"))
 188                                                 kill_tincd = SIGKILL;
 189                                         else if(!strcasecmp(optarg, "USR1"))
 190                                                 kill_tincd = SIGUSR1;
 191                                         else if(!strcasecmp(optarg, "USR2"))
 192                                                 kill_tincd = SIGUSR2;
 193                                         else if(!strcasecmp(optarg, "WINCH"))
 194                                                 kill_tincd = SIGWINCH;
 195                                         else if(!strcasecmp(optarg, "INT"))
 196                                                 kill_tincd = SIGINT;
 197                                         else if(!strcasecmp(optarg, "ALRM"))
 198                                                 kill_tincd = SIGALRM;
 199                                         else {
 200                                                 kill_tincd = atoi(optarg);
 201
 202                                                 if(!kill_tincd) {
 203                                                         fprintf(stderr, "Invalid argument `%s'; SIGNAL must be a number or one of HUP, TERM, KILL, USR1, USR2, WINCH, INT or ALRM.\n",
 204                                                                         optarg);
 205                                                         usage(true);
 206                                                         return false;
 207                                                 }
 208                                         }
 209                                 } else
 210                                         kill_tincd = SIGTERM;
 211 #else
 212                                         kill_tincd = 1;
 213 #endif
 214                                 break;
 215
 216                         case 'n':                               /* net name given */
 217                                 netname = xstrdup(optarg);
 218                                 break;
 219
 220                         case 'K':                               /* generate public/private keypair */
 221                                 if(optarg) {
 222                                         generate_keys = atoi(optarg);
 223
 224                                         if(generate_keys < 512) {
 225                                                 fprintf(stderr, "Invalid argument `%s'; BITS must be a number equal to or greater than 512.\n",
 226                                                                 optarg);
 227                                                 usage(true);
 228                                                 return false;
 229                                         }
 230
 231                                         generate_keys &= ~7;    /* Round it to bytes */
 232                                 } else
 233                                         generate_keys = 2048;
 234                                 break;
 235
 236                         case 'R':                               /* chroot to NETNAME dir */
 237                                 do_chroot = true;
 238                                 break;
 239
 240                         case 'U':                               /* setuid to USER */
 241                                 switchuser = optarg;
 242                                 break;
 243
 244                         case 1:                                 /* show help */
 245                                 show_help = true;
 246                                 break;
 247
 248                         case 2:                                 /* show version */
 249                                 show_version = true;
 250                                 break;
 251
 252                         case 3:                                 /* bypass security */
 253                                 bypass_security = true;
 254                                 break;
 255
 256                         case 4:                                 /* write log entries to a file */
 257                                 use_logfile = true;
 258                                 if(optarg)
 259                                         logfilename = xstrdup(optarg);
 260                                 break;
 261
 262                         case 5:                                 /* write PID to a file */
 263                                 pidfilename = xstrdup(optarg);
 264                                 break;
 265
 266                         case '?':
 267                                 usage(true);
 268                                 return false;
 269
 270                         default:
 271                                 break;
 272                 }
 273         }
 274
 275         return true;
 276 }
 277
 278 /* This function prettyprints the key generation process */
 279
 280 static void indicator(int a, int b, void *p) {
 281         switch (a) {
 282                 case 0:
 283                         fprintf(stderr, ".");
 284                         break;
 285
 286                 case 1:
 287                         fprintf(stderr, "+");
 288                         break;
 289
 290                 case 2:
 291                         fprintf(stderr, "-");
 292                         break;
 293
 294                 case 3:
 295                         switch (b) {
 296                                 case 0:
 297                                         fprintf(stderr, " p\n");
 298                                         break;
 299
 300                                 case 1:
 301                                         fprintf(stderr, " q\n");
 302                                         break;
 303
 304                                 default:
 305                                         fprintf(stderr, "?");
 306                         }
 307                         break;
 308
 309                 default:
 310                         fprintf(stderr, "?");
 311         }
 312 }
 313
 314 /*
 315   Generate a public/private RSA keypair, and ask for a file to store
 316   them in.
 317 */
 318 static bool keygen(int bits) {
 319         RSA *rsa_key;
 320         FILE *f;
 321         char *name = NULL;
 322         char *filename;
 323
 324         get_config_string(lookup_config(config_tree, "Name"), &name);
 325
 326         if(name && !check_id(name)) {
 327                 fprintf(stderr, "Invalid name for myself!\n");
 328                 return false;
 329         }
 330
 331         fprintf(stderr, "Generating %d bits keys:\n", bits);
 332         rsa_key = RSA_generate_key(bits, 0x10001, indicator, NULL);
 333
 334         if(!rsa_key) {
 335                 fprintf(stderr, "Error during key generation!\n");
 336                 return false;
 337         } else
 338                 fprintf(stderr, "Done.\n");
 339
 340         xasprintf(&filename, "%s/rsa_key.priv", confbase);
 341         f = ask_and_open(filename, "private RSA key");
 342
 343         if(!f)
 344                 return false;
 345
 346         if(disable_old_keys(f))
 347                 fprintf(stderr, "Warning: old key(s) found and disabled.\n");
 348
 349 #ifdef HAVE_FCHMOD
 350         /* Make it unreadable for others. */
 351         fchmod(fileno(f), 0600);
 352 #endif
 353
 354         PEM_write_RSAPrivateKey(f, rsa_key, NULL, NULL, 0, NULL, NULL);
 355         fclose(f);
 356         free(filename);
 357
 358         if(name)
 359                 xasprintf(&filename, "%s/hosts/%s", confbase, name);
 360         else
 361                 xasprintf(&filename, "%s/rsa_key.pub", confbase);
 362
 363         f = ask_and_open(filename, "public RSA key");
 364
 365         if(!f)
 366                 return false;
 367
 368         if(disable_old_keys(f))
 369                 fprintf(stderr, "Warning: old key(s) found and disabled.\n");
 370
 371         PEM_write_RSAPublicKey(f, rsa_key);
 372         fclose(f);
 373         free(filename);
 374         if(name)
 375                 free(name);
 376
 377         return true;
 378 }
 379
 380 /*
 381   Set all files and paths according to netname
 382 */
 383 static void make_names(void) {
 384 #ifdef HAVE_MINGW
 385         HKEY key;
 386         char installdir[1024] = "";
 387         long len = sizeof(installdir);
 388 #endif
 389
 390         if(netname)
 391                 xasprintf(&identname, "tinc.%s", netname);
 392         else
 393                 identname = xstrdup("tinc");
 394
 395 #ifdef HAVE_MINGW
 396         if(!RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\tinc", 0, KEY_READ, &key)) {
 397                 if(!RegQueryValueEx(key, NULL, 0, 0, installdir, &len)) {
 398                         if(!logfilename)
 399                                 xasprintf(&logfilename, "%s/log/%s.log", identname);
 400                         if(!confbase) {
 401                                 if(netname)
 402                                         xasprintf(&confbase, "%s/%s", installdir, netname);
 403                                 else
 404                                         xasprintf(&confbase, "%s", installdir);
 405                         }
 406                 }
 407                 RegCloseKey(key);
 408                 if(*installdir)
 409                         return;
 410         }
 411 #endif
 412
 413         if(!pidfilename)
 414                 xasprintf(&pidfilename, LOCALSTATEDIR "/run/%s.pid", identname);
 415
 416         if(!logfilename)
 417                 xasprintf(&logfilename, LOCALSTATEDIR "/log/%s.log", identname);
 418
 419         if(netname) {
 420                 if(!confbase)
 421                         xasprintf(&confbase, CONFDIR "/tinc/%s", netname);
 422                 else
 423                         logger(LOG_INFO, "Both netname and configuration directory given, using the latter...");
 424         } else {
 425                 if(!confbase)
 426                         xasprintf(&confbase, CONFDIR "/tinc");
 427         }
 428 }
 429
 430 static void free_names() {
 431         if (identname) free(identname);
 432         if (netname) free(netname);
 433         if (pidfilename) free(pidfilename);
 434         if (logfilename) free(logfilename);
 435         if (confbase) free(confbase);
 436 }
 437
 438 static bool drop_privs() {
 439 #ifdef HAVE_MINGW
 440         if (switchuser) {
 441                 logger(LOG_ERR, "%s not supported on this platform", "-U");
 442                 return false;
 443         }
 444         if (do_chroot) {
 445                 logger(LOG_ERR, "%s not supported on this platform", "-R");
 446                 return false;
 447         }
 448 #else
 449         uid_t uid = 0;
 450         if (switchuser) {
 451                 struct passwd *pw = getpwnam(switchuser);
 452                 if (!pw) {
 453                         logger(LOG_ERR, "unknown user `%s'", switchuser);
 454                         return false;
 455                 }
 456                 uid = pw->pw_uid;
 457                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 458                     setgid(pw->pw_gid) != 0) {
 459                         logger(LOG_ERR, "System call `%s' failed: %s",
 460                                "initgroups", strerror(errno));
 461                         return false;
 462                 }
 463                 endgrent();
 464                 endpwent();
 465         }
 466         if (do_chroot) {
 467                 tzset();        /* for proper timestamps in logs */
 468                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 469                         logger(LOG_ERR, "System call `%s' failed: %s",
 470                                "chroot", strerror(errno));
 471                         return false;
 472                 }
 473                 free(confbase);
 474                 confbase = xstrdup("");
 475         }
 476         if (switchuser)
 477                 if (setuid(uid) != 0) {
 478                         logger(LOG_ERR, "System call `%s' failed: %s",
 479                                "setuid", strerror(errno));
 480                         return false;
 481                 }
 482 #endif
 483         return true;
 484 }
 485
 486 #ifdef HAVE_MINGW
 487 # define setpriority(level) SetPriorityClass(GetCurrentProcess(), level)
 488 #else
 489 # define NORMAL_PRIORITY_CLASS 0
 490 # define BELOW_NORMAL_PRIORITY_CLASS 10
 491 # define HIGH_PRIORITY_CLASS -10
 492 # define setpriority(level) nice(level)
 493 #endif
 494
 495 int main(int argc, char **argv) {
 496         program_name = argv[0];
 497
 498         if(!parse_options(argc, argv))
 499                 return 1;
 500
 501         make_names();
 502
 503         if(show_version) {
 504                 printf("%s version %s (built %s %s, protocol %d)\n", PACKAGE,
 505                            VERSION, __DATE__, __TIME__, PROT_CURRENT);
 506                 printf("Copyright (C) 1998-2010 Ivo Timmermans, Guus Sliepen and others.\n"
 507                                 "See the AUTHORS file for a complete list.\n\n"
 508                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 509                                 "and you are welcome to redistribute it under certain conditions;\n"
 510                                 "see the file COPYING for details.\n");
 511
 512                 return 0;
 513         }
 514
 515         if(show_help) {
 516                 usage(false);
 517                 return 0;
 518         }
 519
 520         if(kill_tincd)
 521                 return !kill_other(kill_tincd);
 522
 523         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 524
 525         g_argv = argv;
 526
 527         init_configuration(&config_tree);
 528
 529         /* Slllluuuuuuurrrrp! */
 530
 531         RAND_load_file("/dev/urandom", 1024);
 532
 533         ENGINE_load_builtin_engines();
 534         ENGINE_register_all_complete();
 535
 536         OpenSSL_add_all_algorithms();
 537
 538         if(generate_keys) {
 539                 read_server_config();
 540                 return !keygen(generate_keys);
 541         }
 542
 543         if(!read_server_config())
 544                 return 1;
 545
 546 #ifdef HAVE_LZO
 547         if(lzo_init() != LZO_E_OK) {
 548                 logger(LOG_ERR, "Error initializing LZO compressor!");
 549                 return 1;
 550         }
 551 #endif
 552
 553 #ifdef HAVE_MINGW
 554         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 555                 logger(LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 556                 return 1;
 557         }
 558
 559         if(!do_detach || !init_service())
 560                 return main2(argc, argv);
 561         else
 562                 return 1;
 563 }
 564
 565 int main2(int argc, char **argv) {
 566         InitializeCriticalSection(&mutex);
 567         EnterCriticalSection(&mutex);
 568 #endif
 569
 570         if(!detach())
 571                 return 1;
 572
 573 #ifdef HAVE_MLOCKALL
 574         /* Lock all pages into memory if requested.
 575          * This has to be done after daemon()/fork() so it works for child.
 576          * No need to do that in parent as it's very short-lived. */
 577         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 578                 logger(LOG_ERR, "System call `%s' failed: %s", "mlockall",
 579                    strerror(errno));
 580                 return 1;
 581         }
 582 #endif
 583
 584         /* Setup sockets and open device. */
 585
 586         if(!setup_network())
 587                 goto end;
 588
 589         /* Initiate all outgoing connections. */
 590
 591         try_outgoing_connections();
 592
 593         /* Change process priority */
 594
 595         char *priority = 0;
 596
 597         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 598                 if(!strcasecmp(priority, "Normal"))
 599                         setpriority(NORMAL_PRIORITY_CLASS);
 600                 else if(!strcasecmp(priority, "Low"))
 601                         setpriority(BELOW_NORMAL_PRIORITY_CLASS);
 602                 else if(!strcasecmp(priority, "High"))
 603                         setpriority(HIGH_PRIORITY_CLASS);
 604                 else {
 605                         logger(LOG_ERR, "Invalid priority `%s`!", priority);
 606                         goto end;
 607                 }
 608         }
 609
 610         /* drop privileges */
 611         if (!drop_privs())
 612                 goto end;
 613
 614         /* Start main loop. It only exits when tinc is killed. */
 615
 616         status = main_loop();
 617
 618         /* Shutdown properly. */
 619
 620         ifdebug(CONNECTIONS)
 621                 dump_device_stats();
 622
 623         close_network_connections();
 624
 625 end:
 626         logger(LOG_NOTICE, "Terminating");
 627
 628 #ifndef HAVE_MINGW
 629         remove_pid(pidfilename);
 630 #endif
 631
 632         EVP_cleanup();
 633         ENGINE_cleanup();
 634         CRYPTO_cleanup_all_ex_data();
 635         ERR_remove_state(0);
 636         ERR_free_strings();
 637
 638         exit_configuration(&config_tree);
 639         free_names();
 640
 641         return status;
 642 }