www.tinc-vpn.org Git - tinc/blob - src/process.c

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2005 Ivo Timmermans,
   4                   2000-2009 Guus Sliepen <guus@tinc-vpn.org>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License along
  17     with this program; if not, write to the Free Software Foundation, Inc.,
  18     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21 #include "system.h"
  22
  23 #include "conf.h"
  24 #include "connection.h"
  25 #include "device.h"
  26 #include "edge.h"
  27 #include "logger.h"
  28 #include "node.h"
  29 #include "pidfile.h"
  30 #include "process.h"
  31 #include "subnet.h"
  32 #include "utils.h"
  33 #include "xalloc.h"
  34
  35 /* If zero, don't detach from the terminal. */
  36 bool do_detach = true;
  37 bool sighup = false;
  38 bool sigalrm = false;
  39
  40 extern char *identname;
  41 extern char *pidfilename;
  42 extern char **g_argv;
  43 extern bool use_logfile;
  44 extern volatile bool running;
  45
  46 sigset_t emptysigset;
  47
  48 static int saved_debug_level = -1;
  49
  50 static void memory_full(int size) {
  51         logger(LOG_ERR, "Memory exhausted (couldn't allocate %d bytes), exitting.", size);
  52         exit(1);
  53 }
  54
  55 /* Some functions the less gifted operating systems might lack... */
  56
  57 #ifdef HAVE_MINGW
  58 extern char *identname;
  59 extern char *program_name;
  60 extern char **g_argv;
  61
  62 static SC_HANDLE manager = NULL;
  63 static SC_HANDLE service = NULL;
  64 static SERVICE_STATUS status = {0};
  65 static SERVICE_STATUS_HANDLE statushandle = 0;
  66
  67 bool install_service(void) {
  68         char command[4096] = "\"";
  69         char **argp;
  70         bool space;
  71         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  72
  73         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  74         if(!manager) {
  75                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
  76                 return false;
  77         }
  78
  79         if(!strchr(program_name, '\\')) {
  80                 GetCurrentDirectory(sizeof command - 1, command + 1);
  81                 strncat(command, "\\", sizeof command - strlen(command));
  82         }
  83
  84         strncat(command, program_name, sizeof command - strlen(command));
  85
  86         strncat(command, "\"", sizeof command - strlen(command));
  87
  88         for(argp = g_argv + 1; *argp; argp++) {
  89                 space = strchr(*argp, ' ');
  90                 strncat(command, " ", sizeof command - strlen(command));
  91
  92                 if(space)
  93                         strncat(command, "\"", sizeof command - strlen(command));
  94
  95                 strncat(command, *argp, sizeof command - strlen(command));
  96
  97                 if(space)
  98                         strncat(command, "\"", sizeof command - strlen(command));
  99         }
 100
 101         service = CreateService(manager, identname, identname,
 102                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 103                         command, NULL, NULL, NULL, NULL, NULL);
 104
 105         if(!service) {
 106                 DWORD lasterror = GetLastError();
 107                 logger(LOG_ERR, "Could not create %s service: %s", identname, winerror(lasterror));
 108                 if(lasterror != ERROR_SERVICE_EXISTS)
 109                         return false;
 110         }
 111
 112         if(service) {
 113                 ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 114                 logger(LOG_INFO, "%s service installed", identname);
 115         } else {
 116                 service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 117         }
 118
 119         if(!StartService(service, 0, NULL))
 120                 logger(LOG_WARNING, "Could not start %s service: %s", identname, winerror(GetLastError()));
 121         else
 122                 logger(LOG_INFO, "%s service started", identname);
 123
 124         return true;
 125 }
 126
 127 bool remove_service(void) {
 128         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 129         if(!manager) {
 130                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
 131                 return false;
 132         }
 133
 134         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 135
 136         if(!service) {
 137                 logger(LOG_ERR, "Could not open %s service: %s", identname, winerror(GetLastError()));
 138                 return false;
 139         }
 140
 141         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 142                 logger(LOG_ERR, "Could not stop %s service: %s", identname, winerror(GetLastError()));
 143         else
 144                 logger(LOG_INFO, "%s service stopped", identname);
 145
 146         if(!DeleteService(service)) {
 147                 logger(LOG_ERR, "Could not remove %s service: %s", identname, winerror(GetLastError()));
 148                 return false;
 149         }
 150
 151         logger(LOG_INFO, "%s service removed", identname);
 152
 153         return true;
 154 }
 155
 156 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 157         switch(request) {
 158                 case SERVICE_CONTROL_INTERROGATE:
 159                         SetServiceStatus(statushandle, &status);
 160                         return NO_ERROR;
 161                 case SERVICE_CONTROL_STOP:
 162                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_STOP");
 163                         break;
 164                 case SERVICE_CONTROL_SHUTDOWN:
 165                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_SHUTDOWN");
 166                         break;
 167                 default:
 168                         logger(LOG_WARNING, "Got unexpected request %d", request);
 169                         return ERROR_CALL_NOT_IMPLEMENTED;
 170         }
 171
 172         if(running) {
 173                 running = false;
 174                 status.dwWaitHint = 30000;
 175                 status.dwCurrentState = SERVICE_STOP_PENDING;
 176                 SetServiceStatus(statushandle, &status);
 177                 return NO_ERROR;
 178         } else {
 179                 status.dwWaitHint = 0;
 180                 status.dwCurrentState = SERVICE_STOPPED;
 181                 SetServiceStatus(statushandle, &status);
 182                 exit(1);
 183         }
 184
 185 }
 186
 187 VOID WINAPI run_service(DWORD argc, LPTSTR* argv) {
 188         int err = 1;
 189         extern int main2(int argc, char **argv);
 190
 191
 192         status.dwServiceType = SERVICE_WIN32;
 193         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 194         status.dwWin32ExitCode = 0;
 195         status.dwServiceSpecificExitCode = 0;
 196         status.dwCheckPoint = 0;
 197
 198         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 199
 200         if (!statushandle) {
 201                 logger(LOG_ERR, "System call `%s' failed: %s", "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 202                 err = 1;
 203         } else {
 204                 status.dwWaitHint = 30000;
 205                 status.dwCurrentState = SERVICE_START_PENDING;
 206                 SetServiceStatus(statushandle, &status);
 207
 208                 status.dwWaitHint = 0;
 209                 status.dwCurrentState = SERVICE_RUNNING;
 210                 SetServiceStatus(statushandle, &status);
 211
 212                 err = main2(argc, argv);
 213
 214                 status.dwWaitHint = 0;
 215                 status.dwCurrentState = SERVICE_STOPPED;
 216                 //status.dwWin32ExitCode = err;
 217                 SetServiceStatus(statushandle, &status);
 218         }
 219
 220         return;
 221 }
 222
 223 bool init_service(void) {
 224         SERVICE_TABLE_ENTRY services[] = {
 225                 {identname, run_service},
 226                 {NULL, NULL}
 227         };
 228
 229         if(!StartServiceCtrlDispatcher(services)) {
 230                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 231                         return false;
 232                 }
 233                 else
 234                         logger(LOG_ERR, "System call `%s' failed: %s", "StartServiceCtrlDispatcher", winerror(GetLastError()));
 235         }
 236
 237         return true;
 238 }
 239 #endif
 240
 241 #ifndef HAVE_MINGW
 242 /*
 243   check for an existing tinc for this net, and write pid to pidfile
 244 */
 245 static bool write_pidfile(void) {
 246         pid_t pid;
 247
 248         pid = check_pid(pidfilename);
 249
 250         if(pid) {
 251                 if(netname)
 252                         fprintf(stderr, "A tincd is already running for net `%s' with pid %ld.\n",
 253                                         netname, (long)pid);
 254                 else
 255                         fprintf(stderr, "A tincd is already running with pid %ld.\n", (long)pid);
 256                 return false;
 257         }
 258
 259         /* if it's locked, write-protected, or whatever */
 260         if(!write_pid(pidfilename)) {
 261                 fprintf(stderr, "Could write pid file %s: %s\n", pidfilename, strerror(errno));
 262                 return false;
 263         }
 264
 265         return true;
 266 }
 267 #endif
 268
 269 /*
 270   kill older tincd for this net
 271 */
 272 bool kill_other(int signal) {
 273 #ifndef HAVE_MINGW
 274         pid_t pid;
 275
 276         pid = read_pid(pidfilename);
 277
 278         if(!pid) {
 279                 if(netname)
 280                         fprintf(stderr, "No other tincd is running for net `%s'.\n",
 281                                         netname);
 282                 else
 283                         fprintf(stderr, "No other tincd is running.\n");
 284                 return false;
 285         }
 286
 287         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 288
 289         /* ESRCH is returned when no process with that pid is found */
 290         if(kill(pid, signal) && errno == ESRCH) {
 291                 if(netname)
 292                         fprintf(stderr, "The tincd for net `%s' is no longer running. ",
 293                                         netname);
 294                 else
 295                         fprintf(stderr, "The tincd is no longer running. ");
 296
 297                 fprintf(stderr, "Removing stale lock file.\n");
 298                 remove_pid(pidfilename);
 299         }
 300
 301         return true;
 302 #else
 303         return remove_service();
 304 #endif
 305 }
 306
 307 /*
 308   Detach from current terminal, write pidfile, kill parent
 309 */
 310 bool detach(void) {
 311         setup_signals();
 312
 313         /* First check if we can open a fresh new pidfile */
 314
 315 #ifndef HAVE_MINGW
 316         if(!write_pidfile())
 317                 return false;
 318
 319         /* If we succeeded in doing that, detach */
 320
 321         closelogger();
 322 #endif
 323
 324         if(do_detach) {
 325 #ifndef HAVE_MINGW
 326                 if(daemon(0, 0)) {
 327                         fprintf(stderr, "Couldn't detach from terminal: %s",
 328                                         strerror(errno));
 329                         return false;
 330                 }
 331
 332                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 333
 334                 if(!write_pid(pidfilename)) {
 335                         fprintf(stderr, "Could not write pid file %s: %s\n", pidfilename, strerror(errno));
 336                         return false;
 337                 }
 338 #else
 339                 if(!statushandle)
 340                         exit(install_service());
 341 #endif
 342         }
 343
 344         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 345
 346         logger(LOG_NOTICE, "tincd %s (%s %s) starting, debug level %d",
 347                            VERSION, __DATE__, __TIME__, debug_level);
 348
 349         xalloc_fail_func = memory_full;
 350
 351         return true;
 352 }
 353
 354 bool execute_script(const char *name, char **envp) {
 355 #ifdef HAVE_SYSTEM
 356         int status, len;
 357         char *scriptname, *p;
 358         int i;
 359
 360 #ifndef HAVE_MINGW
 361         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 362 #else
 363         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 364 #endif
 365         if(len < 0)
 366                 return false;
 367
 368         scriptname[len - 1] = '\0';
 369
 370 #ifndef HAVE_TUNEMU
 371         /* First check if there is a script */
 372
 373         if(access(scriptname + 1, F_OK)) {
 374                 free(scriptname);
 375                 return true;
 376         }
 377 #endif
 378
 379         ifdebug(STATUS) logger(LOG_INFO, "Executing script %s", name);
 380
 381 #ifdef HAVE_PUTENV
 382         /* Set environment */
 383
 384         for(i = 0; envp[i]; i++)
 385                 putenv(envp[i]);
 386 #endif
 387
 388         scriptname[len - 1] = '\"';
 389         status = system(scriptname);
 390
 391         free(scriptname);
 392
 393         /* Unset environment */
 394
 395         for(i = 0; envp[i]; i++) {
 396                 char *e = strchr(envp[i], '=');
 397                 if(e) {
 398                         p = alloca(e - envp[i] + 1);
 399                         strncpy(p, envp[i], e - envp[i]);
 400                         p[e - envp[i]] = '\0';
 401                         putenv(p);
 402                 }
 403         }
 404
 405 #ifdef WEXITSTATUS
 406         if(status != -1) {
 407                 if(WIFEXITED(status)) { /* Child exited by itself */
 408                         if(WEXITSTATUS(status)) {
 409                                 logger(LOG_ERR, "Script %s exited with non-zero status %d",
 410                                            name, WEXITSTATUS(status));
 411                                 return false;
 412                         }
 413                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 414                         logger(LOG_ERR, "Script %s was killed by signal %d (%s)",
 415                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 416                         return false;
 417                 } else {                        /* Something strange happened */
 418                         logger(LOG_ERR, "Script %s terminated abnormally", name);
 419                         return false;
 420                 }
 421         } else {
 422                 logger(LOG_ERR, "System call `%s' failed: %s", "system", strerror(errno));
 423                 return false;
 424         }
 425 #endif
 426 #endif
 427         return true;
 428 }
 429
 430
 431 /*
 432   Signal handlers.
 433 */
 434
 435 #ifndef HAVE_MINGW
 436 static RETSIGTYPE sigterm_handler(int a) {
 437         logger(LOG_NOTICE, "Got %s signal", "TERM");
 438         if(running)
 439                 running = false;
 440         else
 441                 exit(1);
 442 }
 443
 444 static RETSIGTYPE sigquit_handler(int a) {
 445         logger(LOG_NOTICE, "Got %s signal", "QUIT");
 446         if(running)
 447                 running = false;
 448         else
 449                 exit(1);
 450 }
 451
 452 static RETSIGTYPE fatal_signal_square(int a) {
 453         logger(LOG_ERR, "Got another fatal signal %d (%s): not restarting.", a,
 454                    strsignal(a));
 455         exit(1);
 456 }
 457
 458 static RETSIGTYPE fatal_signal_handler(int a) {
 459         struct sigaction act;
 460         logger(LOG_ERR, "Got fatal signal %d (%s)", a, strsignal(a));
 461
 462         if(do_detach) {
 463                 logger(LOG_NOTICE, "Trying to re-execute in 5 seconds...");
 464
 465                 act.sa_handler = fatal_signal_square;
 466                 act.sa_mask = emptysigset;
 467                 act.sa_flags = 0;
 468                 sigaction(SIGSEGV, &act, NULL);
 469
 470                 close_network_connections();
 471                 sleep(5);
 472                 remove_pid(pidfilename);
 473                 execvp(g_argv[0], g_argv);
 474         } else {
 475                 logger(LOG_NOTICE, "Not restarting.");
 476                 exit(1);
 477         }
 478 }
 479
 480 static RETSIGTYPE sighup_handler(int a) {
 481         logger(LOG_NOTICE, "Got %s signal", "HUP");
 482         sighup = true;
 483 }
 484
 485 static RETSIGTYPE sigint_handler(int a) {
 486         logger(LOG_NOTICE, "Got %s signal", "INT");
 487
 488         if(saved_debug_level != -1) {
 489                 logger(LOG_NOTICE, "Reverting to old debug level (%d)",
 490                         saved_debug_level);
 491                 debug_level = saved_debug_level;
 492                 saved_debug_level = -1;
 493         } else {
 494                 logger(LOG_NOTICE,
 495                         "Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d.",
 496                         debug_level);
 497                 saved_debug_level = debug_level;
 498                 debug_level = 5;
 499         }
 500 }
 501
 502 static RETSIGTYPE sigalrm_handler(int a) {
 503         logger(LOG_NOTICE, "Got %s signal", "ALRM");
 504         sigalrm = true;
 505 }
 506
 507 static RETSIGTYPE sigusr1_handler(int a) {
 508         dump_connections();
 509 }
 510
 511 static RETSIGTYPE sigusr2_handler(int a) {
 512         dump_device_stats();
 513         dump_nodes();
 514         dump_edges();
 515         dump_subnets();
 516 }
 517
 518 static RETSIGTYPE sigwinch_handler(int a) {
 519         do_purge = true;
 520 }
 521
 522 static RETSIGTYPE unexpected_signal_handler(int a) {
 523         logger(LOG_WARNING, "Got unexpected signal %d (%s)", a, strsignal(a));
 524 }
 525
 526 static RETSIGTYPE ignore_signal_handler(int a) {
 527         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignored signal %d (%s)", a, strsignal(a));
 528 }
 529
 530 static struct {
 531         int signal;
 532         void (*handler)(int);
 533 } sighandlers[] = {
 534         {SIGHUP, sighup_handler},
 535         {SIGTERM, sigterm_handler},
 536         {SIGQUIT, sigquit_handler},
 537         {SIGSEGV, fatal_signal_handler},
 538         {SIGBUS, fatal_signal_handler},
 539         {SIGILL, fatal_signal_handler},
 540         {SIGPIPE, ignore_signal_handler},
 541         {SIGINT, sigint_handler},
 542         {SIGUSR1, sigusr1_handler},
 543         {SIGUSR2, sigusr2_handler},
 544         {SIGCHLD, ignore_signal_handler},
 545         {SIGALRM, sigalrm_handler},
 546         {SIGWINCH, sigwinch_handler},
 547         {0, NULL}
 548 };
 549 #endif
 550
 551 void setup_signals(void) {
 552 #ifndef HAVE_MINGW
 553         int i;
 554         struct sigaction act;
 555
 556         sigemptyset(&emptysigset);
 557         act.sa_handler = NULL;
 558         act.sa_mask = emptysigset;
 559         act.sa_flags = 0;
 560
 561         /* Set a default signal handler for every signal, errors will be
 562            ignored. */
 563         for(i = 1; i < NSIG; i++) {
 564                 if(!do_detach)
 565                         act.sa_handler = SIG_DFL;
 566                 else
 567                         act.sa_handler = unexpected_signal_handler;
 568                 sigaction(i, &act, NULL);
 569         }
 570
 571         /* If we didn't detach, allow coredumps */
 572         if(!do_detach)
 573                 sighandlers[3].handler = SIG_DFL;
 574
 575         /* Then, for each known signal that we want to catch, assign a
 576            handler to the signal, with error checking this time. */
 577         for(i = 0; sighandlers[i].signal; i++) {
 578                 act.sa_handler = sighandlers[i].handler;
 579                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 580                         fprintf(stderr, "Installing signal handler for signal %d (%s) failed: %s\n",
 581                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 582                                         strerror(errno));
 583         }
 584 #endif
 585 }