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