tinc-vpn.org Git - tinc/blob - src/tincd.c

   1 /*
   2     tincd.c -- the main file for tincd
   3     Copyright (C) 1998-2005 Ivo Timmermans
   4                   2000-2015 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 "event.h"
  53 #include "logger.h"
  54 #include "names.h"
  55 #include "net.h"
  56 #include "netutl.h"
  57 #include "process.h"
  58 #include "protocol.h"
  59 #include "utils.h"
  60 #include "xalloc.h"
  61 #include "version.h"
  62
  63 /* If nonzero, display usage information and exit. */
  64 static bool show_help = false;
  65
  66 /* If nonzero, print the version on standard output and exit.  */
  67 static bool show_version = false;
  68
  69 /* If nonzero, use null ciphers and skip all key exchanges. */
  70 bool bypass_security = false;
  71
  72 #ifdef HAVE_MLOCKALL
  73 /* If nonzero, disable swapping for this process. */
  74 static bool do_mlock = false;
  75 #endif
  76
  77 #ifndef HAVE_MINGW
  78 /* If nonzero, chroot to netdir after startup. */
  79 static bool do_chroot = false;
  80
  81 /* If !NULL, do setuid to given user after startup */
  82 static const char *switchuser = NULL;
  83 #endif
  84
  85 /* If nonzero, write log entries to a separate file. */
  86 bool use_logfile = false;
  87
  88 /* If nonzero, use syslog instead of stderr in no-detach mode. */
  89 bool use_syslog = false;
  90
  91 char **g_argv;                  /* a copy of the cmdline arguments */
  92
  93 static int status = 1;
  94
  95 static struct option const long_options[] = {
  96         {"config", required_argument, NULL, 'c'},
  97         {"net", required_argument, NULL, 'n'},
  98         {"help", no_argument, NULL, 1},
  99         {"version", no_argument, NULL, 2},
 100         {"no-detach", no_argument, NULL, 'D'},
 101         {"debug", optional_argument, NULL, 'd'},
 102         {"bypass-security", no_argument, NULL, 3},
 103         {"mlock", no_argument, NULL, 'L'},
 104         {"chroot", no_argument, NULL, 'R'},
 105         {"user", required_argument, NULL, 'U'},
 106         {"logfile", optional_argument, NULL, 4},
 107         {"syslog", no_argument, NULL, 's'},
 108         {"pidfile", required_argument, NULL, 5},
 109         {"option", required_argument, NULL, 'o'},
 110         {NULL, 0, NULL, 0}
 111 };
 112
 113 #ifdef HAVE_MINGW
 114 static struct WSAData wsa_state;
 115 int main2(int argc, char **argv);
 116 #endif
 117
 118 static void usage(bool status) {
 119         if(status)
 120                 fprintf(stderr, "Try `%s --help\' for more information.\n",
 121                                 program_name);
 122         else {
 123                 printf("Usage: %s [option]...\n\n", program_name);
 124                 printf( "  -c, --config=DIR              Read configuration options from DIR.\n"
 125                                 "  -D, --no-detach               Don't fork and detach.\n"
 126                                 "  -d, --debug[=LEVEL]           Increase debug level or set it to LEVEL.\n"
 127                                 "  -n, --net=NETNAME             Connect to net NETNAME.\n"
 128 #ifdef HAVE_MLOCKALL
 129                                 "  -L, --mlock                   Lock tinc into main memory.\n"
 130 #endif
 131                                 "      --logfile[=FILENAME]      Write log entries to a logfile.\n"
 132                                 "  -s  --syslog                  Use syslog instead of stderr with --no-detach.\n"
 133                                 "      --pidfile=FILENAME        Write PID and control socket cookie to FILENAME.\n"
 134                                 "      --bypass-security         Disables meta protocol security, for debugging.\n"
 135                                 "  -o, --option[HOST.]KEY=VALUE  Set global/host configuration value.\n"
 136 #ifndef HAVE_MINGW
 137                                 "  -R, --chroot                  chroot to NET dir at startup.\n"
 138                                 "  -U, --user=USER               setuid to given USER at startup.\n"
 139 #endif
 140                                 "      --help                    Display this help and exit.\n"
 141                                 "      --version                 Output version information and exit.\n\n");
 142                 printf("Report bugs to tinc@tinc-vpn.org.\n");
 143         }
 144 }
 145
 146 static bool parse_options(int argc, char **argv) {
 147         config_t *cfg;
 148         int r;
 149         int option_index = 0;
 150         int lineno = 0;
 151
 152         cmdline_conf = list_alloc((list_action_t)free_config);
 153
 154         while((r = getopt_long(argc, argv, "c:DLd::n:so:RU:", long_options, &option_index)) != EOF) {
 155                 switch (r) {
 156                         case 0:   /* long option */
 157                                 break;
 158
 159                         case 'c': /* config file */
 160                                 confbase = xstrdup(optarg);
 161                                 break;
 162
 163                         case 'D': /* no detach */
 164                                 do_detach = false;
 165                                 break;
 166
 167                         case 'L': /* no detach */
 168 #ifndef HAVE_MLOCKALL
 169                                 logger(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 170                                 return false;
 171 #else
 172                                 do_mlock = true;
 173                                 break;
 174 #endif
 175
 176                         case 'd': /* increase debug level */
 177                                 if(!optarg && optind < argc && *argv[optind] != '-')
 178                                         optarg = argv[optind++];
 179                                 if(optarg)
 180                                         debug_level = atoi(optarg);
 181                                 else
 182                                         debug_level++;
 183                                 break;
 184
 185                         case 'n': /* net name given */
 186                                 netname = xstrdup(optarg);
 187                                 break;
 188
 189                         case 's': /* syslog */
 190                                 use_logfile = false;
 191                                 use_syslog = true;
 192                                 break;
 193
 194                         case 'o': /* option */
 195                                 cfg = parse_config_line(optarg, NULL, ++lineno);
 196                                 if (!cfg)
 197                                         return false;
 198                                 list_insert_tail(cmdline_conf, cfg);
 199                                 break;
 200
 201 #ifdef HAVE_MINGW
 202                         case 'R':
 203                         case 'U':
 204                                 logger(DEBUG_ALWAYS, LOG_ERR, "The %s option is not supported on this platform.", argv[optind - 1]);
 205                                 return false;
 206 #else
 207                         case 'R': /* chroot to NETNAME dir */
 208                                 do_chroot = true;
 209                                 break;
 210
 211                         case 'U': /* setuid to USER */
 212                                 switchuser = optarg;
 213                                 break;
 214 #endif
 215
 216                         case 1:   /* show help */
 217                                 show_help = true;
 218                                 break;
 219
 220                         case 2:   /* show version */
 221                                 show_version = true;
 222                                 break;
 223
 224                         case 3:   /* bypass security */
 225                                 bypass_security = true;
 226                                 break;
 227
 228                         case 4:   /* write log entries to a file */
 229                                 use_syslog = false;
 230                                 use_logfile = true;
 231                                 if(!optarg && optind < argc && *argv[optind] != '-')
 232                                         optarg = argv[optind++];
 233                                 if(optarg)
 234                                         logfilename = xstrdup(optarg);
 235                                 break;
 236
 237                         case 5:   /* open control socket here */
 238                                 pidfilename = xstrdup(optarg);
 239                                 break;
 240
 241                         case '?': /* wrong options */
 242                                 usage(true);
 243                                 return false;
 244
 245                         default:
 246                                 break;
 247                 }
 248         }
 249
 250         if(optind < argc) {
 251                 fprintf(stderr, "%s: unrecognized argument '%s'\n", argv[0], argv[optind]);
 252                 usage(true);
 253                 return false;
 254         }
 255
 256         if(!netname && (netname = getenv("NETNAME")))
 257                 netname = xstrdup(netname);
 258
 259         /* netname "." is special: a "top-level name" */
 260
 261         if(netname && (!*netname || !strcmp(netname, "."))) {
 262                 free(netname);
 263                 netname = NULL;
 264         }
 265
 266         if(netname && (strpbrk(netname, "\\/") || *netname == '.')) {
 267                 fprintf(stderr, "Invalid character in netname!\n");
 268                 return false;
 269         }
 270
 271         return true;
 272 }
 273
 274 static bool drop_privs(void) {
 275 #ifndef HAVE_MINGW
 276         uid_t uid = 0;
 277         if (switchuser) {
 278                 struct passwd *pw = getpwnam(switchuser);
 279                 if (!pw) {
 280                         logger(DEBUG_ALWAYS, LOG_ERR, "unknown user `%s'", switchuser);
 281                         return false;
 282                 }
 283                 uid = pw->pw_uid;
 284                 if (initgroups(switchuser, pw->pw_gid) != 0 ||
 285                     setgid(pw->pw_gid) != 0) {
 286                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 287                                "initgroups", strerror(errno));
 288                         return false;
 289                 }
 290 #ifndef __ANDROID__
 291 // Not supported in android NDK
 292                 endgrent();
 293                 endpwent();
 294 #endif
 295         }
 296         if (do_chroot) {
 297                 tzset();        /* for proper timestamps in logs */
 298                 if (chroot(confbase) != 0 || chdir("/") != 0) {
 299                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 300                                "chroot", strerror(errno));
 301                         return false;
 302                 }
 303                 free(confbase);
 304                 confbase = xstrdup("");
 305         }
 306         if (switchuser)
 307                 if (setuid(uid) != 0) {
 308                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s",
 309                                "setuid", strerror(errno));
 310                         return false;
 311                 }
 312 #endif
 313         return true;
 314 }
 315
 316 #ifdef HAVE_MINGW
 317 # define setpriority(level) !SetPriorityClass(GetCurrentProcess(), (level))
 318
 319 static void stop_handler(void *data, int flags) {
 320         event_exit();
 321 }
 322
 323 static BOOL WINAPI console_ctrl_handler(DWORD type) {
 324         logger(DEBUG_ALWAYS, LOG_NOTICE, "Got console shutdown request");
 325         if (WSASetEvent(stop_io.event) == FALSE)
 326                 abort();
 327         return TRUE;
 328 }
 329 #else
 330 # define NORMAL_PRIORITY_CLASS 0
 331 # define BELOW_NORMAL_PRIORITY_CLASS 10
 332 # define HIGH_PRIORITY_CLASS -10
 333 # define setpriority(level) (setpriority(PRIO_PROCESS, 0, (level)))
 334 #endif
 335
 336 int main(int argc, char **argv) {
 337         program_name = argv[0];
 338
 339         if(!parse_options(argc, argv))
 340                 return 1;
 341
 342         make_names(true);
 343
 344         if(show_version) {
 345                 printf("%s version %s (built %s %s, protocol %d.%d)\n", PACKAGE,
 346                            BUILD_VERSION, BUILD_DATE, BUILD_TIME, PROT_MAJOR, PROT_MINOR);
 347                 printf("Copyright (C) 1998-2015 Ivo Timmermans, Guus Sliepen and others.\n"
 348                                 "See the AUTHORS file for a complete list.\n\n"
 349                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 350                                 "and you are welcome to redistribute it under certain conditions;\n"
 351                                 "see the file COPYING for details.\n");
 352
 353                 return 0;
 354         }
 355
 356         if(show_help) {
 357                 usage(false);
 358                 return 0;
 359         }
 360
 361 #ifdef HAVE_MINGW
 362         if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
 363                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 364                 return 1;
 365         }
 366 #else
 367         // Check if we got an umbilical fd from the process that started us
 368         char *umbstr = getenv("TINC_UMBILICAL");
 369         if(umbstr) {
 370                 umbilical = atoi(umbstr);
 371                 if(fcntl(umbilical, F_GETFL) < 0)
 372                         umbilical = 0;
 373 #ifdef FD_CLOEXEC
 374                 if(umbilical)
 375                         fcntl(umbilical, F_SETFD, FD_CLOEXEC);
 376 #endif
 377         }
 378 #endif
 379
 380         openlogger("tinc", use_logfile?LOGMODE_FILE:LOGMODE_STDERR);
 381
 382         g_argv = argv;
 383
 384         if(getenv("LISTEN_PID") && atoi(getenv("LISTEN_PID")) == getpid())
 385                 do_detach = false;
 386 #ifdef HAVE_UNSETENV
 387         unsetenv("LISTEN_PID");
 388 #endif
 389
 390         init_configuration(&config_tree);
 391
 392         /* Slllluuuuuuurrrrp! */
 393
 394         gettimeofday(&now, NULL);
 395         srand(now.tv_sec + now.tv_usec);
 396         crypto_init();
 397
 398         if(!read_server_config())
 399                 return 1;
 400
 401 #ifdef HAVE_LZO
 402         if(lzo_init() != LZO_E_OK) {
 403                 logger(DEBUG_ALWAYS, LOG_ERR, "Error initializing LZO compressor!");
 404                 return 1;
 405         }
 406 #endif
 407
 408 #ifdef HAVE_MINGW
 409         io_add_event(&stop_io, stop_handler, NULL, WSACreateEvent());
 410         if (stop_io.event == FALSE)
 411                 abort();
 412
 413         int result;
 414         if(!do_detach || !init_service()) {
 415                 SetConsoleCtrlHandler(console_ctrl_handler, TRUE);
 416                 result = main2(argc, argv);
 417         } else
 418                 result = 1;
 419
 420         if (WSACloseEvent(stop_io.event) == FALSE)
 421                 abort();
 422         io_del(&stop_io);
 423         return result;
 424 }
 425
 426 int main2(int argc, char **argv) {
 427 #endif
 428         char *priority = NULL;
 429
 430         if(!detach())
 431                 return 1;
 432
 433 #ifdef HAVE_MLOCKALL
 434         /* Lock all pages into memory if requested.
 435          * This has to be done after daemon()/fork() so it works for child.
 436          * No need to do that in parent as it's very short-lived. */
 437         if(do_mlock && mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
 438                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "mlockall",
 439                    strerror(errno));
 440                 return 1;
 441         }
 442 #endif
 443
 444         /* Setup sockets and open device. */
 445
 446         if(!setup_network())
 447                 goto end;
 448
 449         /* Change process priority */
 450
 451         if(get_config_string(lookup_config(config_tree, "ProcessPriority"), &priority)) {
 452                 if(!strcasecmp(priority, "Normal")) {
 453                         if (setpriority(NORMAL_PRIORITY_CLASS) != 0) {
 454                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 455                                 goto end;
 456                         }
 457                 } else if(!strcasecmp(priority, "Low")) {
 458                         if (setpriority(BELOW_NORMAL_PRIORITY_CLASS) != 0) {
 459                                        logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 460                                 goto end;
 461                         }
 462                 } else if(!strcasecmp(priority, "High")) {
 463                         if (setpriority(HIGH_PRIORITY_CLASS) != 0) {
 464                                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setpriority", strerror(errno));
 465                                 goto end;
 466                         }
 467                 } else {
 468                         logger(DEBUG_ALWAYS, LOG_ERR, "Invalid priority `%s`!", priority);
 469                         goto end;
 470                 }
 471         }
 472
 473         /* drop privileges */
 474         if (!drop_privs())
 475                 goto end;
 476
 477         /* Start main loop. It only exits when tinc is killed. */
 478
 479         logger(DEBUG_ALWAYS, LOG_NOTICE, "Ready");
 480
 481         if(umbilical) { // snip!
 482                 write(umbilical, "", 1);
 483                 close(umbilical);
 484                 umbilical = 0;
 485         }
 486
 487         try_outgoing_connections();
 488
 489         status = main_loop();
 490
 491         /* Shutdown properly. */
 492
 493 end:
 494         close_network_connections();
 495
 496         logger(DEBUG_ALWAYS, LOG_NOTICE, "Terminating");
 497
 498         free(priority);
 499
 500         crypto_exit();
 501
 502         exit_configuration(&config_tree);
 503         free(cmdline_conf);
 504         free_names();
 505
 506         return status;
 507 }