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