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': /* increase debug level */
 171                                 if(!optarg && optind < argc && *argv[optind] != '-')
 172                                         optarg = argv[optind++];
 173                                 if(optarg)
 174                                         debug_level = atoi(optarg);
 175                                 else
 176                                         debug_level++;
 177                                 break;
 178
 179                         case 'n': /* net name given */
 180                                 netname = xstrdup(optarg);
 181                                 break;
 182
 183                         case 'o': /* option */
 184                                 cfg = parse_config_line(optarg, NULL, ++lineno);
 185                                 if (!cfg)
 186                                         return false;
 187                                 list_insert_tail(cmdline_conf, cfg);
 188                                 break;
 189
 190 #ifdef HAVE_MINGW
 191                         case 'R':
 192                         case 'U':
 193                                 logger(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 194                                 return false;
 195 #else
 196                         case 'R': /* chroot to NETNAME dir */
 197                                 do_chroot = true;
 198                                 break;
 199
 200                         case 'U': /* setuid to USER */
 201                                 switchuser = optarg;
 202                                 break;
 203 #endif
 204
 205                         case 1:   /* show help */
 206                                 show_help = true;
 207                                 break;
 208
 209                         case 2:   /* show version */
 210                                 show_version = true;
 211                                 break;
 212
 213                         case 3:   /* bypass security */
 214                                 bypass_security = true;
 215                                 break;
 216
 217                         case 4:   /* write log entries to a file */
 218                                 use_logfile = true;
 219                                 if(!optarg && optind < argc && *argv[optind] != '-')
 220                                         optarg = argv[optind++];
 221                                 if(optarg)
 222                                         logfilename = xstrdup(optarg);
 223                                 break;
 224
 225                         case 5:   /* open control socket here */
 226                                 pidfilename = xstrdup(optarg);
 227                                 break;
 228
 229                         case '?': /* wrong options */
 230                                 usage(true);
 231                                 return false;
 232
 233                         default:
 234                                 break;
 235                 }
 236         }
 237
 238         if(optind < argc) {
 239                 fprintf(stderr, "%s: unrecognized argument '%s'\n", argv[0], argv[optind]);
 240                 usage(true);
 241                 return false;
 242         }
 243
 244         if(!netname && (netname = getenv("NETNAME")))
 245                 netname = xstrdup(netname);
 246
 247         /* netname "." is special: a "top-level name" */
 248
 249         if(netname && (!*netname || !strcmp(netname, "."))) {
 250                 free(netname);
 251                 netname = NULL;
 252         }
 253
 254         if(netname && (strpbrk(netname, "\\/") || *netname == '.')) {
 255                 fprintf(stderr, "Invalid character in netname!\n");
 256                 return false;
 257         }
 258
 259         return true;
 260 }
 261
 262 static bool drop_privs(void) {
 263 #ifndef HAVE_MINGW
 264         uid_t uid = 0;
 265         if (switchuser) {
 266                 struct passwd *pw = getpwnam(switchuser);
 267                 if (!pw) {
 268                         logger(DEBUG_ALWAYS, LOG_ERR, "unknown user `%s'", switchuser);
 269                         return false;
 270                 }
 271                 uid = pw->pw_uid;
 272                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 273                     setgid(pw->pw_gid) != 0) {
 274                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 275                                "initgroups", strerror(errno));
 276                         return false;
 277                 }
 278 #ifndef __ANDROID__
 279 // Not supported in android NDK
 280                 endgrent();
 281                 endpwent();
 282 #endif
 283         }
 284         if (do_chroot) {
 285                 tzset();        /* for proper timestamps in logs */
 286                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 287                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 288                                "chroot", strerror(errno));
 289                         return false;
 290                 }
 291                 free(confbase);
 292                 confbase = xstrdup("");
 293         }
 294         if (switchuser)
 295                 if (setuid(uid) != 0) {
 296                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 297                                "setuid", strerror(errno));
 298                         return false;
 299                 }
 300 #endif
 301         return true;
 302 }
 303
 304 #ifdef HAVE_MINGW
 305 # define setpriority(level) !SetPriorityClass(GetCurrentProcess(), (level))
 306 #else
 307 # define NORMAL_PRIORITY_CLASS 0
 308 # define BELOW_NORMAL_PRIORITY_CLASS 10
 309 # define HIGH_PRIORITY_CLASS -10
 310 # define setpriority(level) (setpriority(PRIO_PROCESS, 0, (level)))
 311 #endif
 312
 313 int main(int argc, char **argv) {
 314         program_name = argv[0];
 315
 316         if(!parse_options(argc, argv))
 317                 return 1;
 318
 319         make_names();
 320
 321         if(show_version) {
 322                 printf("%s version %s (built %s %s, protocol %d.%d)\n", PACKAGE,
 323                            VERSION, __DATE__, __TIME__, PROT_MAJOR, PROT_MINOR);
 324                 printf("Copyright (C) 1998-2013 Ivo Timmermans, Guus Sliepen and others.\n"
 325                                 "See the AUTHORS file for a complete list.\n\n"
 326                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 327                                 "and you are welcome to redistribute it under certain conditions;\n"
 328                                 "see the file COPYING for details.\n");
 329
 330                 return 0;
 331         }
 332
 333         if(show_help) {
 334                 usage(false);
 335                 return 0;
 336         }
 337
 338 #ifdef HAVE_MINGW
 339         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 340                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 341                 return 1;
 342         }
 343 #endif
 344
 345         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 346
 347         g_argv = argv;
 348
 349         if(getenv("LISTEN_PID") && atoi(getenv("LISTEN_PID")) == getpid())
 350                 do_detach = false;
 351 #ifdef HAVE_UNSETENV
 352         unsetenv("LISTEN_PID");
 353 #endif
 354
 355         init_configuration(&config_tree);
 356
 357         /* Slllluuuuuuurrrrp! */
 358
 359         gettimeofday(&now, NULL);
 360         srand(now.tv_sec + now.tv_usec);
 361         crypto_init();
 362
 363         if(!read_server_config())
 364                 return 1;
 365
 366 #ifdef HAVE_LZO
 367         if(lzo_init() != LZO_E_OK) {
 368                 logger(DEBUG_ALWAYS, LOG_ERR, "Error initializing LZO compressor!");
 369                 return 1;
 370         }
 371 #endif
 372
 373 #ifdef HAVE_MINGW
 374         if(!do_detach || !init_service())
 375                 return main2(argc, argv);
 376         else
 377                 return 1;
 378 }
 379
 380 int main2(int argc, char **argv) {
 381         InitializeCriticalSection(&mutex);
 382         EnterCriticalSection(&mutex);
 383 #endif
 384         char *priority = NULL;
 385
 386         if(!detach())
 387                 return 1;
 388
 389 #ifdef HAVE_MLOCKALL
 390         /* Lock all pages into memory if requested.
 391          * This has to be done after daemon()/fork() so it works for child.
 392          * No need to do that in parent as it's very short-lived. */
 393         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 394                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "mlockall",
 395                    strerror(errno));
 396                 return 1;
 397         }
 398 #endif
 399
 400         /* Setup sockets and open device. */
 401
 402         if(!setup_network())
 403                 goto end;
 404
 405         /* Change process priority */
 406
 407         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 408                 if(!strcasecmp(priority, "Normal")) {
 409                         if (setpriority(NORMAL_PRIORITY_CLASS) != 0) {
 410                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 411                                 goto end;
 412                         }
 413                 } else if(!strcasecmp(priority, "Low")) {
 414                         if (setpriority(BELOW_NORMAL_PRIORITY_CLASS) != 0) {
 415                                        logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 416                                 goto end;
 417                         }
 418                 } else if(!strcasecmp(priority, "High")) {
 419                         if (setpriority(HIGH_PRIORITY_CLASS) != 0) {
 420                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 421                                 goto end;
 422                         }
 423                 } else {
 424                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid priority `%s`!", priority);
 425                         goto end;
 426                 }
 427         }
 428
 429         /* drop privileges */
 430         if (!drop_privs())
 431                 goto end;
 432
 433         /* Start main loop. It only exits when tinc is killed. */
 434
 435         logger(DEBUG_ALWAYS, LOG_NOTICE, "Ready");
 436
 437         try_outgoing_connections();
 438
 439         status = main_loop();
 440
 441         /* Shutdown properly. */
 442
 443         if(debug_level >= DEBUG_CONNECTIONS)
 444                 devops.dump_stats();
 445
 446 end:
 447         close_network_connections();
 448
 449         logger(DEBUG_ALWAYS, LOG_NOTICE, "Terminating");
 450
 451         free(priority);
 452
 453         crypto_exit();
 454
 455         exit_configuration(&config_tree);
 456         free(cmdline_conf);
 457         free_names();
 458
 459         return status;
 460 }