src/tincd.c

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