git.meshlink.io Git - meshlink/blob - src/tincd.c

   1 /*
   2     tincd.c -- the main file for tincd
   3     Copyright (C) 1998-2005 Ivo Timmermans
   4                   2000-2014 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 #ifdef HAVE_LZO
  37 #include LZO1X_H
  38 #endif
  39
  40 #ifndef HAVE_MINGW
  41 #include <pwd.h>
  42 #include <grp.h>
  43 #include <time.h>
  44 #endif
  45
  46 #include <getopt.h>
  47
  48 #include "conf.h"
  49 #include "crypto.h"
  50 #include "logger.h"
  51 #include "names.h"
  52 #include "net.h"
  53 #include "netutl.h"
  54 #include "process.h"
  55 #include "protocol.h"
  56 #include "utils.h"
  57 #include "xalloc.h"
  58
  59 /* If nonzero, display usage information and exit. */
  60 static bool show_help = false;
  61
  62 /* If nonzero, print the version on standard output and exit.  */
  63 static bool show_version = false;
  64
  65 /* If nonzero, use null ciphers and skip all key exchanges. */
  66 bool bypass_security = false;
  67
  68 #ifdef HAVE_MLOCKALL
  69 /* If nonzero, disable swapping for this process. */
  70 static bool do_mlock = false;
  71 #endif
  72
  73 #ifndef HAVE_MINGW
  74 /* If nonzero, chroot to netdir after startup. */
  75 static bool do_chroot = false;
  76
  77 /* If !NULL, do setuid to given user after startup */
  78 static const char *switchuser = NULL;
  79 #endif
  80
  81 /* If nonzero, write log entries to a separate file. */
  82 bool use_logfile = false;
  83
  84 char **g_argv;                  /* a copy of the cmdline arguments */
  85
  86 static int status = 1;
  87
  88 static struct option const long_options[] = {
  89         {"config", required_argument, NULL, 'c'},
  90         {"net", required_argument, NULL, 'n'},
  91         {"help", no_argument, NULL, 1},
  92         {"version", no_argument, NULL, 2},
  93         {"no-detach", no_argument, NULL, 'D'},
  94         {"debug", optional_argument, NULL, 'd'},
  95         {"bypass-security", no_argument, NULL, 3},
  96         {"mlock", no_argument, NULL, 'L'},
  97         {"chroot", no_argument, NULL, 'R'},
  98         {"user", required_argument, NULL, 'U'},
  99         {"logfile", optional_argument, NULL, 4},
 100         {"pidfile", required_argument, NULL, 5},
 101         {"option", required_argument, NULL, 'o'},
 102         {NULL, 0, NULL, 0}
 103 };
 104
 105 #ifdef HAVE_MINGW
 106 static struct WSAData wsa_state;
 107 CRITICAL_SECTION mutex;
 108 int main2(int argc, char **argv);
 109 #endif
 110
 111 static void usage(bool status) {
 112         if(status)
 113                 fprintf(stderr, "Try `%s --help\' for more information.\n",
 114                                 program_name);
 115         else {
 116                 printf("Usage: %s [option]...\n\n", program_name);
 117                 printf( "  -c, --config=DIR              Read configuration options from DIR.\n"
 118                                 "  -D, --no-detach               Don't fork and detach.\n"
 119                                 "  -d, --debug[=LEVEL]           Increase debug level or set it to LEVEL.\n"
 120                                 "  -n, --net=NETNAME             Connect to net NETNAME.\n"
 121 #ifdef HAVE_MLOCKALL
 122                                 "  -L, --mlock                   Lock tinc into main memory.\n"
 123 #endif
 124                                 "      --logfile[=FILENAME]      Write log entries to a logfile.\n"
 125                                 "      --pidfile=FILENAME        Write PID and control socket cookie to FILENAME.\n"
 126                                 "      --bypass-security         Disables meta protocol security, for debugging.\n"
 127                                 "  -o, --option[HOST.]KEY=VALUE  Set global/host configuration value.\n"
 128 #ifndef HAVE_MINGW
 129                                 "  -R, --chroot                  chroot to NET dir at startup.\n"
 130                                 "  -U, --user=USER               setuid to given USER at startup.\n"
 131 #endif
 132                                 "      --help                    Display this help and exit.\n"
 133                                 "      --version                 Output version information and exit.\n\n");
 134                 printf("Report bugs to tinc@tinc-vpn.org.\n");
 135         }
 136 }
 137
 138 static bool parse_options(int argc, char **argv) {
 139         config_t *cfg;
 140         int r;
 141         int option_index = 0;
 142         int lineno = 0;
 143
 144         cmdline_conf = list_alloc((list_action_t)free_config);
 145
 146         while((r = getopt_long(argc, argv, "c:DLd::n:o:RU:", long_options, &option_index)) != EOF) {
 147                 switch (r) {
 148                         case 0:   /* long option */
 149                                 break;
 150
 151                         case 'c': /* config file */
 152                                 confbase = xstrdup(optarg);
 153                                 break;
 154
 155                         case 'D': /* no detach */
 156                                 do_detach = false;
 157                                 break;
 158
 159                         case 'L': /* no detach */
 160 #ifndef HAVE_MLOCKALL
 161                                 logger(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 162                                 return false;
 163 #else
 164                                 do_mlock = true;
 165                                 break;
 166 #endif
 167
 168                         case 'd': /* increase debug level */
 169                                 if(!optarg && optind < argc && *argv[optind] != '-')
 170                                         optarg = argv[optind++];
 171                                 if(optarg)
 172                                         debug_level = atoi(optarg);
 173                                 else
 174                                         debug_level++;
 175                                 break;
 176
 177                         case 'n': /* net name given */
 178                                 netname = xstrdup(optarg);
 179                                 break;
 180
 181                         case 'o': /* option */
 182                                 cfg = parse_config_line(optarg, NULL, ++lineno);
 183                                 if (!cfg)
 184                                         return false;
 185                                 list_insert_tail(cmdline_conf, cfg);
 186                                 break;
 187
 188 #ifdef HAVE_MINGW
 189                         case 'R':
 190                         case 'U':
 191                                 logger(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 192                                 return false;
 193 #else
 194                         case 'R': /* chroot to NETNAME dir */
 195                                 do_chroot = true;
 196                                 break;
 197
 198                         case 'U': /* setuid to USER */
 199                                 switchuser = optarg;
 200                                 break;
 201 #endif
 202
 203                         case 1:   /* show help */
 204                                 show_help = true;
 205                                 break;
 206
 207                         case 2:   /* show version */
 208                                 show_version = true;
 209                                 break;
 210
 211                         case 3:   /* bypass security */
 212                                 bypass_security = true;
 213                                 break;
 214
 215                         case 4:   /* write log entries to a file */
 216                                 use_logfile = true;
 217                                 if(!optarg && optind < argc && *argv[optind] != '-')
 218                                         optarg = argv[optind++];
 219                                 if(optarg)
 220                                         logfilename = xstrdup(optarg);
 221                                 break;
 222
 223                         case 5:   /* open control socket here */
 224                                 pidfilename = xstrdup(optarg);
 225                                 break;
 226
 227                         case '?': /* wrong options */
 228                                 usage(true);
 229                                 return false;
 230
 231                         default:
 232                                 break;
 233                 }
 234         }
 235
 236         if(optind < argc) {
 237                 fprintf(stderr, "%s: unrecognized argument '%s'\n", argv[0], argv[optind]);
 238                 usage(true);
 239                 return false;
 240         }
 241
 242         if(!netname && (netname = getenv("NETNAME")))
 243                 netname = xstrdup(netname);
 244
 245         /* netname "." is special: a "top-level name" */
 246
 247         if(netname && (!*netname || !strcmp(netname, "."))) {
 248                 free(netname);
 249                 netname = NULL;
 250         }
 251
 252         if(netname && (strpbrk(netname, "\\/") || *netname == '.')) {
 253                 fprintf(stderr, "Invalid character in netname!\n");
 254                 return false;
 255         }
 256
 257         return true;
 258 }
 259
 260 static bool drop_privs(void) {
 261 #ifndef HAVE_MINGW
 262         uid_t uid = 0;
 263         if (switchuser) {
 264                 struct passwd *pw = getpwnam(switchuser);
 265                 if (!pw) {
 266                         logger(DEBUG_ALWAYS, LOG_ERR, "unknown user `%s'", switchuser);
 267                         return false;
 268                 }
 269                 uid = pw->pw_uid;
 270                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 271                     setgid(pw->pw_gid) != 0) {
 272                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 273                                "initgroups", strerror(errno));
 274                         return false;
 275                 }
 276 #ifndef __ANDROID__
 277 // Not supported in android NDK
 278                 endgrent();
 279                 endpwent();
 280 #endif
 281         }
 282         if (do_chroot) {
 283                 tzset();        /* for proper timestamps in logs */
 284                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 285                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 286                                "chroot", strerror(errno));
 287                         return false;
 288                 }
 289                 free(confbase);
 290                 confbase = xstrdup("");
 291         }
 292         if (switchuser)
 293                 if (setuid(uid) != 0) {
 294                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 295                                "setuid", strerror(errno));
 296                         return false;
 297                 }
 298 #endif
 299         return true;
 300 }
 301
 302 #ifdef HAVE_MINGW
 303 # define setpriority(level) !SetPriorityClass(GetCurrentProcess(), (level))
 304 #else
 305 # define NORMAL_PRIORITY_CLASS 0
 306 # define BELOW_NORMAL_PRIORITY_CLASS 10
 307 # define HIGH_PRIORITY_CLASS -10
 308 # define setpriority(level) (setpriority(PRIO_PROCESS, 0, (level)))
 309 #endif
 310
 311 int main(int argc, char **argv) {
 312         program_name = argv[0];
 313
 314         if(!parse_options(argc, argv))
 315                 return 1;
 316
 317         make_names();
 318
 319         if(show_version) {
 320                 printf("%s version %s (built %s %s, protocol %d.%d)\n", PACKAGE,
 321                            VERSION, __DATE__, __TIME__, PROT_MAJOR, PROT_MINOR);
 322                 printf("Copyright (C) 1998-2014 Ivo Timmermans, Guus Sliepen and others.\n"
 323                                 "See the AUTHORS file for a complete list.\n\n"
 324                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 325                                 "and you are welcome to redistribute it under certain conditions;\n"
 326                                 "see the file COPYING for details.\n");
 327
 328                 return 0;
 329         }
 330
 331         if(show_help) {
 332                 usage(false);
 333                 return 0;
 334         }
 335
 336 #ifdef HAVE_MINGW
 337         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 338                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 339                 return 1;
 340         }
 341 #endif
 342
 343         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 344
 345         g_argv = argv;
 346
 347         if(getenv("LISTEN_PID") && atoi(getenv("LISTEN_PID")) == getpid())
 348                 do_detach = false;
 349 #ifdef HAVE_UNSETENV
 350         unsetenv("LISTEN_PID");
 351 #endif
 352
 353         init_configuration(&config_tree);
 354
 355         /* Slllluuuuuuurrrrp! */
 356
 357         gettimeofday(&now, NULL);
 358         srand(now.tv_sec + now.tv_usec);
 359         crypto_init();
 360
 361         if(!read_server_config())
 362                 return 1;
 363
 364 #ifdef HAVE_LZO
 365         if(lzo_init() != LZO_E_OK) {
 366                 logger(DEBUG_ALWAYS, LOG_ERR, "Error initializing LZO compressor!");
 367                 return 1;
 368         }
 369 #endif
 370
 371 #ifdef HAVE_MINGW
 372         if(!do_detach || !init_service())
 373                 return main2(argc, argv);
 374         else
 375                 return 1;
 376 }
 377
 378 int main2(int argc, char **argv) {
 379         InitializeCriticalSection(&mutex);
 380         EnterCriticalSection(&mutex);
 381 #endif
 382         char *priority = NULL;
 383
 384         if(!detach())
 385                 return 1;
 386
 387 #ifdef HAVE_MLOCKALL
 388         /* Lock all pages into memory if requested.
 389          * This has to be done after daemon()/fork() so it works for child.
 390          * No need to do that in parent as it's very short-lived. */
 391         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 392                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "mlockall",
 393                    strerror(errno));
 394                 return 1;
 395         }
 396 #endif
 397
 398         /* Setup sockets. */
 399
 400         if(!setup_network())
 401                 goto end;
 402
 403         /* Change process priority */
 404
 405         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 406                 if(!strcasecmp(priority, "Normal")) {
 407                         if (setpriority(NORMAL_PRIORITY_CLASS) != 0) {
 408                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 409                                 goto end;
 410                         }
 411                 } else if(!strcasecmp(priority, "Low")) {
 412                         if (setpriority(BELOW_NORMAL_PRIORITY_CLASS) != 0) {
 413                                        logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 414                                 goto end;
 415                         }
 416                 } else if(!strcasecmp(priority, "High")) {
 417                         if (setpriority(HIGH_PRIORITY_CLASS) != 0) {
 418                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 419                                 goto end;
 420                         }
 421                 } else {
 422                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid priority `%s`!", priority);
 423                         goto end;
 424                 }
 425         }
 426
 427         /* drop privileges */
 428         if (!drop_privs())
 429                 goto end;
 430
 431         /* Start main loop. It only exits when tinc is killed. */
 432
 433         logger(DEBUG_ALWAYS, LOG_NOTICE, "Ready");
 434
 435         try_outgoing_connections();
 436
 437         status = main_loop();
 438
 439         /* Shutdown properly. */
 440
 441 end:
 442         close_network_connections();
 443
 444         logger(DEBUG_ALWAYS, LOG_NOTICE, "Terminating");
 445
 446         free(priority);
 447
 448         crypto_exit();
 449
 450         exit_configuration(&config_tree);
 451         free(cmdline_conf);
 452         free_names();
 453
 454         return status;
 455 }