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                   2000-2013 Guus Sliepen <guus@tinc-vpn.org>
   5                   2008      Max Rijevski <maksuf@gmail.com>
   6                   2009      Michael Tokarev <mjt@tls.msk.ru>
   7                   2010      Julien Muchembled <jm@jmuchemb.eu>
   8                   2010      Timothy Redaelli <timothy@redaelli.eu>
   9
  10     This program is free software; you can redistribute it and/or modify
  11     it under the terms of the GNU General Public License as published by
  12     the Free Software Foundation; either version 2 of the License, or
  13     (at your option) any later version.
  14
  15     This program is distributed in the hope that it will be useful,
  16     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18     GNU General Public License for more details.
  19
  20     You should have received a copy of the GNU General Public License along
  21     with this program; if not, write to the Free Software Foundation, Inc.,
  22     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  23 */
  24
  25 #include "system.h"
  26
  27 /* Darwin (MacOS/X) needs the following definition... */
  28 #ifndef _P1003_1B_VISIBLE
  29 #define _P1003_1B_VISIBLE
  30 #endif
  31
  32 #ifdef HAVE_SYS_MMAN_H
  33 #include <sys/mman.h>
  34 #endif
  35
  36 #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 "control.h"
  50 #include "crypto.h"
  51 #include "device.h"
  52 #include "logger.h"
  53 #include "names.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 /* If nonzero, display usage information and exit. */
  62 static bool show_help = false;
  63
  64 /* If nonzero, print the version on standard output and exit.  */
  65 static bool show_version = false;
  66
  67 /* If nonzero, use null ciphers and skip all key exchanges. */
  68 bool bypass_security = false;
  69
  70 #ifdef HAVE_MLOCKALL
  71 /* If nonzero, disable swapping for this process. */
  72 static bool do_mlock = false;
  73 #endif
  74
  75 #ifndef HAVE_MINGW
  76 /* If nonzero, chroot to netdir after startup. */
  77 static bool do_chroot = false;
  78
  79 /* If !NULL, do setuid to given user after startup */
  80 static const char *switchuser = NULL;
  81 #endif
  82
  83 /* If nonzero, write log entries to a separate file. */
  84 bool use_logfile = false;
  85
  86 char **g_argv;                  /* a copy of the cmdline arguments */
  87
  88 static int status = 1;
  89
  90 static struct option const long_options[] = {
  91         {"config", required_argument, NULL, 'c'},
  92         {"net", required_argument, NULL, 'n'},
  93         {"help", no_argument, NULL, 1},
  94         {"version", no_argument, NULL, 2},
  95         {"no-detach", no_argument, NULL, 'D'},
  96         {"debug", optional_argument, NULL, 'd'},
  97         {"bypass-security", no_argument, NULL, 3},
  98         {"mlock", no_argument, NULL, 'L'},
  99         {"chroot", no_argument, NULL, 'R'},
 100         {"user", required_argument, NULL, 'U'},
 101         {"logfile", optional_argument, NULL, 4},
 102         {"pidfile", required_argument, NULL, 5},
 103         {"option", required_argument, NULL, 'o'},
 104         {NULL, 0, NULL, 0}
 105 };
 106
 107 #ifdef HAVE_MINGW
 108 static struct WSAData wsa_state;
 109 CRITICAL_SECTION mutex;
 110 int main2(int argc, char **argv);
 111 #endif
 112
 113 static void usage(bool status) {
 114         if(status)
 115                 fprintf(stderr, "Try `%s --help\' for more information.\n",
 116                                 program_name);
 117         else {
 118                 printf("Usage: %s [option]...\n\n", program_name);
 119                 printf( "  -c, --config=DIR              Read configuration options from DIR.\n"
 120                                 "  -D, --no-detach               Don't fork and detach.\n"
 121                                 "  -d, --debug[=LEVEL]           Increase debug level or set it to LEVEL.\n"
 122                                 "  -n, --net=NETNAME             Connect to net NETNAME.\n"
 123 #ifdef HAVE_MLOCKALL
 124                                 "  -L, --mlock                   Lock tinc into main memory.\n"
 125 #endif
 126                                 "      --logfile[=FILENAME]      Write log entries to a logfile.\n"
 127                                 "      --pidfile=FILENAME        Write PID and control socket cookie to FILENAME.\n"
 128                                 "      --bypass-security         Disables meta protocol security, for debugging.\n"
 129                                 "  -o, --option[HOST.]KEY=VALUE  Set global/host configuration value.\n"
 130 #ifndef HAVE_MINGW
 131                                 "  -R, --chroot                  chroot to NET dir at startup.\n"
 132                                 "  -U, --user=USER               setuid to given USER at startup.\n"
 133 #endif
 134                                 "      --help                    Display this help and exit.\n"
 135                                 "      --version                 Output version information and exit.\n\n");
 136                 printf("Report bugs to tinc@tinc-vpn.org.\n");
 137         }
 138 }
 139
 140 static bool parse_options(int argc, char **argv) {
 141         config_t *cfg;
 142         int r;
 143         int option_index = 0;
 144         int lineno = 0;
 145
 146         cmdline_conf = list_alloc((list_action_t)free_config);
 147
 148         while((r = getopt_long(argc, argv, "c:DLd::n:o: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(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 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 '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)
 218                                         logfilename = xstrdup(optarg);
 219                                 break;
 220
 221                         case 5:   /* open control socket here */
 222                                 pidfilename = xstrdup(optarg);
 223                                 break;
 224
 225                         case '?': /* wrong options */
 226                                 usage(true);
 227                                 return false;
 228
 229                         default:
 230                                 break;
 231                 }
 232         }
 233
 234         if(!netname && (netname = getenv("NETNAME")))
 235                 netname = xstrdup(netname);
 236
 237         /* netname "." is special: a "top-level name" */
 238
 239         if(netname && (!*netname || !strcmp(netname, "."))) {
 240                 free(netname);
 241                 netname = NULL;
 242         }
 243
 244         if(netname && (strpbrk(netname, "\\/") || *netname == '.')) {
 245                 fprintf(stderr, "Invalid character in netname!\n");
 246                 return false;
 247         }
 248
 249         return true;
 250 }
 251
 252 static bool drop_privs(void) {
 253 #ifndef HAVE_MINGW
 254         uid_t uid = 0;
 255         if (switchuser) {
 256                 struct passwd *pw = getpwnam(switchuser);
 257                 if (!pw) {
 258                         logger(DEBUG_ALWAYS, LOG_ERR, "unknown user `%s'", switchuser);
 259                         return false;
 260                 }
 261                 uid = pw->pw_uid;
 262                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 263                     setgid(pw->pw_gid) != 0) {
 264                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 265                                "initgroups", strerror(errno));
 266                         return false;
 267                 }
 268 #ifndef __ANDROID__
 269 // Not supported in android NDK
 270                 endgrent();
 271                 endpwent();
 272 #endif
 273         }
 274         if (do_chroot) {
 275                 tzset();        /* for proper timestamps in logs */
 276                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 277                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 278                                "chroot", strerror(errno));
 279                         return false;
 280                 }
 281                 free(confbase);
 282                 confbase = xstrdup("");
 283         }
 284         if (switchuser)
 285                 if (setuid(uid) != 0) {
 286                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 287                                "setuid", strerror(errno));
 288                         return false;
 289                 }
 290 #endif
 291         return true;
 292 }
 293
 294 #ifdef HAVE_MINGW
 295 # define setpriority(level) !SetPriorityClass(GetCurrentProcess(), (level))
 296 #else
 297 # define NORMAL_PRIORITY_CLASS 0
 298 # define BELOW_NORMAL_PRIORITY_CLASS 10
 299 # define HIGH_PRIORITY_CLASS -10
 300 # define setpriority(level) (setpriority(PRIO_PROCESS, 0, (level)))
 301 #endif
 302
 303 int main(int argc, char **argv) {
 304         program_name = argv[0];
 305
 306         if(!parse_options(argc, argv))
 307                 return 1;
 308
 309         make_names();
 310
 311         if(show_version) {
 312                 printf("%s version %s (built %s %s, protocol %d.%d)\n", PACKAGE,
 313                            VERSION, __DATE__, __TIME__, PROT_MAJOR, PROT_MINOR);
 314                 printf("Copyright (C) 1998-2012 Ivo Timmermans, Guus Sliepen and others.\n"
 315                                 "See the AUTHORS file for a complete list.\n\n"
 316                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 317                                 "and you are welcome to redistribute it under certain conditions;\n"
 318                                 "see the file COPYING for details.\n");
 319
 320                 return 0;
 321         }
 322
 323         if(show_help) {
 324                 usage(false);
 325                 return 0;
 326         }
 327
 328 #ifdef HAVE_MINGW
 329         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 330                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 331                 return 1;
 332         }
 333 #endif
 334
 335         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 336
 337         g_argv = argv;
 338
 339         if(getenv("LISTEN_PID") && atoi(getenv("LISTEN_PID")) == getpid())
 340                 do_detach = false;
 341 #ifdef HAVE_UNSETENV
 342         unsetenv("LISTEN_PID");
 343 #endif
 344
 345         init_configuration(&config_tree);
 346
 347         /* Slllluuuuuuurrrrp! */
 348
 349         gettimeofday(&now, NULL);
 350         srand(now.tv_sec + now.tv_usec);
 351         crypto_init();
 352
 353         if(!read_server_config())
 354                 return 1;
 355
 356 #ifdef HAVE_LZO
 357         if(lzo_init() != LZO_E_OK) {
 358                 logger(DEBUG_ALWAYS, LOG_ERR, "Error initializing LZO compressor!");
 359                 return 1;
 360         }
 361 #endif
 362
 363 #ifdef HAVE_MINGW
 364         if(!do_detach || !init_service())
 365                 return main2(argc, argv);
 366         else
 367                 return 1;
 368 }
 369
 370 int main2(int argc, char **argv) {
 371         InitializeCriticalSection(&mutex);
 372         EnterCriticalSection(&mutex);
 373 #endif
 374         char *priority = NULL;
 375
 376         if(!detach())
 377                 return 1;
 378
 379 #ifdef HAVE_MLOCKALL
 380         /* Lock all pages into memory if requested.
 381          * This has to be done after daemon()/fork() so it works for child.
 382          * No need to do that in parent as it's very short-lived. */
 383         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 384                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "mlockall",
 385                    strerror(errno));
 386                 return 1;
 387         }
 388 #endif
 389
 390         /* Setup sockets and open device. */
 391
 392         if(!setup_network())
 393                 goto end_nonet;
 394
 395         if(!init_control())
 396                 goto end_nonet;
 397
 398         /* Initiate all outgoing connections. */
 399
 400         try_outgoing_connections();
 401
 402         /* Change process priority */
 403
 404         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 405                 if(!strcasecmp(priority, "Normal")) {
 406                         if (setpriority(NORMAL_PRIORITY_CLASS) != 0) {
 407                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 408                                 goto end;
 409                         }
 410                 } else if(!strcasecmp(priority, "Low")) {
 411                         if (setpriority(BELOW_NORMAL_PRIORITY_CLASS) != 0) {
 412                                        logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 413                                 goto end;
 414                         }
 415                 } else if(!strcasecmp(priority, "High")) {
 416                         if (setpriority(HIGH_PRIORITY_CLASS) != 0) {
 417                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 418                                 goto end;
 419                         }
 420                 } else {
 421                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid priority `%s`!", priority);
 422                         goto end;
 423                 }
 424         }
 425
 426         /* drop privileges */
 427         if (!drop_privs())
 428                 goto end;
 429
 430         /* Start main loop. It only exits when tinc is killed. */
 431
 432         status = main_loop();
 433
 434         /* Shutdown properly. */
 435
 436         if(debug_level >= DEBUG_CONNECTIONS)
 437                 devops.dump_stats();
 438
 439         close_network_connections();
 440
 441 end:
 442         exit_control();
 443
 444 end_nonet:
 445         logger(DEBUG_ALWAYS, LOG_NOTICE, "Terminating");
 446
 447         free(priority);
 448
 449         crypto_exit();
 450
 451         exit_configuration(&config_tree);
 452         free(cmdline_conf);
 453         free_names();
 454
 455         return status;
 456 }