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