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

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2003 Ivo Timmermans <ivo@o2w.nl>,
   4                   2000-2003 Guus Sliepen <guus@sliepen.eu.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
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: process.c,v 1.1.2.73 2003/08/17 12:05:08 guus Exp $
  21 */
  22
  23 #include "system.h"
  24
  25 #include "conf.h"
  26 #include "connection.h"
  27 #include "device.h"
  28 #include "edge.h"
  29 #include "logger.h"
  30 #include "node.h"
  31 #include "pidfile.h"
  32 #include "process.h"
  33 #include "subnet.h"
  34 #include "utils.h"
  35 #include "xalloc.h"
  36
  37 /* If zero, don't detach from the terminal. */
  38 bool do_detach = true;
  39 bool sighup = false;
  40 bool sigalrm = false;
  41
  42 extern char *identname;
  43 extern char *pidfilename;
  44 extern char **g_argv;
  45 extern bool use_logfile;
  46 extern volatile bool running;
  47
  48 sigset_t emptysigset;
  49
  50 static int saved_debug_level = -1;
  51
  52 static void memory_full(int size)
  53 {
  54         logger(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size);
  55         cp_trace();
  56         exit(1);
  57 }
  58
  59 /* Some functions the less gifted operating systems might lack... */
  60
  61 #ifndef HAVE_FCLOSEALL
  62 static int fcloseall(void)
  63 {
  64         fflush(stdin);
  65         fflush(stdout);
  66         fflush(stderr);
  67         fclose(stdin);
  68         fclose(stdout);
  69         fclose(stderr);
  70         return 0;
  71 }
  72 #endif
  73
  74 #ifdef HAVE_MINGW
  75 extern char *identname;
  76 extern char *program_name;
  77 extern char **g_argv;
  78
  79 static SC_HANDLE manager = NULL;
  80 static SC_HANDLE service = NULL;
  81 static SERVICE_STATUS status = {0};
  82 static SERVICE_STATUS_HANDLE statushandle = 0;
  83
  84 bool install_service(void) {
  85         char command[4096] = "";
  86         char **argp;
  87         bool space;
  88         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  89
  90         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  91         if(!manager) {
  92                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  93                 return false;
  94         }
  95
  96         strncat(command, "\"", sizeof(command));
  97
  98         if(!strchr(program_name, '\\')) {
  99                 GetCurrentDirectory(sizeof(command), command);
 100                 strncat(command, "\\", sizeof(command));
 101         }
 102
 103         strncat(command, program_name, sizeof(command));
 104
 105         strncat(command, "\"", sizeof(command));
 106
 107         for(argp = g_argv + 1; *argp; argp++) {
 108                 space = strchr(*argp, ' ');
 109                 strncat(command, " ", sizeof(command));
 110
 111                 if(space)
 112                         strncat(command, "\"", sizeof(command));
 113
 114                 strncat(command, *argp, sizeof(command));
 115
 116                 if(space)
 117                         strncat(command, "\"", sizeof(command));
 118         }
 119
 120         service = CreateService(manager, identname, identname,
 121                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 122                         command, "NDIS", NULL, NULL, NULL, NULL);
 123
 124         if(!service) {
 125                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 126                 return false;
 127         }
 128
 129         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 130
 131         logger(LOG_INFO, _("%s service installed"), identname);
 132
 133         if(!StartService(service, 0, NULL))
 134                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 135         else
 136                 logger(LOG_INFO, _("%s service started"), identname);
 137
 138         return true;
 139 }
 140
 141 bool remove_service(void) {
 142         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 143         if(!manager) {
 144                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 145                 return false;
 146         }
 147
 148         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 149
 150         if(!service) {
 151                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 152                 return false;
 153         }
 154
 155         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 156                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 157         else
 158                 logger(LOG_INFO, _("%s service stopped"), identname);
 159
 160         if(!DeleteService(service)) {
 161                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 162                 return false;
 163         }
 164
 165         logger(LOG_INFO, _("%s service removed"), identname);
 166
 167         return true;
 168 }
 169
 170 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 171         switch(request) {
 172                 case SERVICE_CONTROL_STOP:
 173                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 174                         break;
 175                 case SERVICE_CONTROL_SHUTDOWN:
 176                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 177                         break;
 178                 default:
 179                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 180                         return ERROR_CALL_NOT_IMPLEMENTED;
 181         }
 182
 183         if(running) {
 184                 running = false;
 185                 status.dwWaitHint = 30000;
 186                 status.dwCurrentState = SERVICE_STOP_PENDING;
 187                 SetServiceStatus(statushandle, &status);
 188                 return NO_ERROR;
 189         } else {
 190                 status.dwWaitHint = 0;
 191                 status.dwCurrentState = SERVICE_STOPPED;
 192                 SetServiceStatus(statushandle, &status);
 193                 exit(1);
 194         }
 195
 196 }
 197
 198 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
 199 {
 200         int err = 1;
 201         extern int main2(int argc, char **argv);
 202
 203
 204         status.dwServiceType = SERVICE_WIN32;
 205         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 206         status.dwWin32ExitCode = 0;
 207         status.dwServiceSpecificExitCode = 0;
 208         status.dwCheckPoint = 0;
 209
 210         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 211
 212         if (!statushandle) {
 213                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 214                 err = 1;
 215         } else {
 216                 status.dwWaitHint = 30000;
 217                 status.dwCurrentState = SERVICE_START_PENDING;
 218                 SetServiceStatus(statushandle, &status);
 219
 220                 status.dwWaitHint = 0;
 221                 status.dwCurrentState = SERVICE_RUNNING;
 222                 SetServiceStatus(statushandle, &status);
 223
 224                 err = main2(argc, argv);
 225
 226                 status.dwWaitHint = 0;
 227                 status.dwCurrentState = SERVICE_STOPPED;
 228                 //status.dwWin32ExitCode = err;
 229                 SetServiceStatus(statushandle, &status);
 230         }
 231
 232         return;
 233 }
 234
 235 bool init_service(void) {
 236         SERVICE_TABLE_ENTRY services[] = {
 237                 {identname, run_service},
 238                 {NULL, NULL}
 239         };
 240
 241         if(!StartServiceCtrlDispatcher(services)) {
 242                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 243                         return false;
 244                 }
 245                 else
 246                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 247         }
 248
 249         return true;
 250 }
 251 #endif
 252
 253 #ifndef HAVE_MINGW
 254 /*
 255   check for an existing tinc for this net, and write pid to pidfile
 256 */
 257 static bool write_pidfile(void)
 258 {
 259         int pid;
 260
 261         cp();
 262
 263         pid = check_pid(pidfilename);
 264
 265         if(pid) {
 266                 if(netname)
 267                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %d.\n"),
 268                                         netname, pid);
 269                 else
 270                         fprintf(stderr, _("A tincd is already running with pid %d.\n"), pid);
 271                 return false;
 272         }
 273
 274         /* if it's locked, write-protected, or whatever */
 275         if(!write_pid(pidfilename))
 276                 return false;
 277
 278         return true;
 279 }
 280 #endif
 281
 282 /*
 283   kill older tincd for this net
 284 */
 285 bool kill_other(int signal)
 286 {
 287 #ifndef HAVE_MINGW
 288         int pid;
 289
 290         cp();
 291
 292         pid = read_pid(pidfilename);
 293
 294         if(!pid) {
 295                 if(netname)
 296                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 297                                         netname);
 298                 else
 299                         fprintf(stderr, _("No other tincd is running.\n"));
 300                 return false;
 301         }
 302
 303         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 304
 305         /* ESRCH is returned when no process with that pid is found */
 306         if(kill(pid, signal) && errno == ESRCH) {
 307                 if(netname)
 308                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 309                                         netname);
 310                 else
 311                         fprintf(stderr, _("The tincd is no longer running. "));
 312
 313                 fprintf(stderr, _("Removing stale lock file.\n"));
 314                 remove_pid(pidfilename);
 315         }
 316
 317         return true;
 318 #else
 319         return remove_service();
 320 #endif
 321 }
 322
 323 /*
 324   Detach from current terminal, write pidfile, kill parent
 325 */
 326 bool detach(void)
 327 {
 328         cp();
 329
 330         setup_signals();
 331
 332         /* First check if we can open a fresh new pidfile */
 333
 334 #ifndef HAVE_MINGW
 335         if(!write_pidfile())
 336                 return false;
 337
 338         /* If we succeeded in doing that, detach */
 339
 340         closelogger();
 341 #endif
 342
 343         if(do_detach) {
 344 #ifndef HAVE_MINGW
 345                 if(daemon(0, 0)) {
 346                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 347                                         strerror(errno));
 348                         return false;
 349                 }
 350
 351                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 352
 353                 if(!write_pid(pidfilename))
 354                         return false;
 355 #else
 356                 if(!statushandle)
 357                         exit(install_service());
 358 #endif
 359         }
 360
 361         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 362
 363         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 364                            VERSION, __DATE__, __TIME__, debug_level);
 365
 366         xalloc_fail_func = memory_full;
 367
 368         return true;
 369 }
 370
 371 bool execute_script(const char *name, char **envp)
 372 {
 373 #ifdef HAVE_SYSTEM
 374         int status, len;
 375         struct stat s;
 376         char *scriptname;
 377
 378         cp();
 379
 380 #ifndef HAVE_MINGW
 381         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 382 #else
 383         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 384 #endif
 385         if(len < 0)
 386                 return false;
 387
 388         scriptname[len - 1] = '\0';
 389
 390         /* First check if there is a script */
 391
 392         if(stat(scriptname + 1, &s))
 393                 return true;
 394
 395         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 396
 397 #ifdef HAVE_PUTENV
 398         /* Set environment */
 399
 400         while(*envp)
 401                 putenv(*envp++);
 402 #endif
 403
 404         scriptname[len - 1] = '\"';
 405         status = system(scriptname);
 406
 407         free(scriptname);
 408
 409         /* Unset environment? */
 410
 411 #ifdef WEXITSTATUS
 412         if(status != -1) {
 413                 if(WIFEXITED(status)) { /* Child exited by itself */
 414                         if(WEXITSTATUS(status)) {
 415                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 416                                            name, WEXITSTATUS(status));
 417                                 return false;
 418                         }
 419                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 420                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 421                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 422                         return false;
 423                 } else {                        /* Something strange happened */
 424                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 425                         return false;
 426                 }
 427         } else {
 428                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 429                 return false;
 430         }
 431 #endif
 432 #endif
 433         return true;
 434 }
 435
 436
 437 /*
 438   Signal handlers.
 439 */
 440
 441 #ifndef HAVE_MINGW
 442 static RETSIGTYPE sigterm_handler(int a)
 443 {
 444         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 445         running = false;
 446 }
 447
 448 static RETSIGTYPE sigquit_handler(int a)
 449 {
 450         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 451         running = false;
 452 }
 453
 454 static RETSIGTYPE fatal_signal_square(int a)
 455 {
 456         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 457                    strsignal(a));
 458         cp_trace();
 459         exit(1);
 460 }
 461
 462 static RETSIGTYPE fatal_signal_handler(int a)
 463 {
 464         struct sigaction act;
 465         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 466         cp_trace();
 467
 468         if(do_detach) {
 469                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 470
 471                 act.sa_handler = fatal_signal_square;
 472                 act.sa_mask = emptysigset;
 473                 act.sa_flags = 0;
 474                 sigaction(SIGSEGV, &act, NULL);
 475
 476                 close_network_connections();
 477                 sleep(5);
 478                 remove_pid(pidfilename);
 479                 execvp(g_argv[0], g_argv);
 480         } else {
 481                 logger(LOG_NOTICE, _("Not restarting."));
 482                 exit(1);
 483         }
 484 }
 485
 486 static RETSIGTYPE sighup_handler(int a)
 487 {
 488         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 489         sighup = true;
 490 }
 491
 492 static RETSIGTYPE sigint_handler(int a)
 493 {
 494         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 495
 496         if(saved_debug_level != -1) {
 497                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 498                         saved_debug_level);
 499                 debug_level = saved_debug_level;
 500                 saved_debug_level = -1;
 501         } else {
 502                 logger(LOG_NOTICE,
 503                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 504                         debug_level);
 505                 saved_debug_level = debug_level;
 506                 debug_level = 5;
 507         }
 508 }
 509
 510 static RETSIGTYPE sigalrm_handler(int a)
 511 {
 512         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 513         sigalrm = true;
 514 }
 515
 516 static RETSIGTYPE sigusr1_handler(int a)
 517 {
 518         dump_connections();
 519 }
 520
 521 static RETSIGTYPE sigusr2_handler(int a)
 522 {
 523         dump_device_stats();
 524         dump_nodes();
 525         dump_edges();
 526         dump_subnets();
 527 }
 528
 529 static RETSIGTYPE sigwinch_handler(int a)
 530 {
 531         do_purge = true;
 532 }
 533
 534 static RETSIGTYPE unexpected_signal_handler(int a)
 535 {
 536         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 537         cp_trace();
 538 }
 539
 540 static RETSIGTYPE ignore_signal_handler(int a)
 541 {
 542         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 543 }
 544
 545 static struct {
 546         int signal;
 547         void (*handler)(int);
 548 } sighandlers[] = {
 549         {SIGHUP, sighup_handler},
 550         {SIGTERM, sigterm_handler},
 551         {SIGQUIT, sigquit_handler},
 552         {SIGSEGV, fatal_signal_handler},
 553         {SIGBUS, fatal_signal_handler},
 554         {SIGILL, fatal_signal_handler},
 555         {SIGPIPE, ignore_signal_handler},
 556         {SIGINT, sigint_handler},
 557         {SIGUSR1, sigusr1_handler},
 558         {SIGUSR2, sigusr2_handler},
 559         {SIGCHLD, ignore_signal_handler},
 560         {SIGALRM, sigalrm_handler},
 561         {SIGWINCH, sigwinch_handler},
 562         {0, NULL}
 563 };
 564 #endif
 565
 566 void setup_signals(void)
 567 {
 568 #ifndef HAVE_MINGW
 569         int i;
 570         struct sigaction act;
 571
 572         sigemptyset(&emptysigset);
 573         act.sa_handler = NULL;
 574         act.sa_mask = emptysigset;
 575         act.sa_flags = 0;
 576
 577         /* Set a default signal handler for every signal, errors will be
 578            ignored. */
 579         for(i = 0; i < NSIG; i++) {
 580                 if(!do_detach)
 581                         act.sa_handler = SIG_DFL;
 582                 else
 583                         act.sa_handler = unexpected_signal_handler;
 584                 sigaction(i, &act, NULL);
 585         }
 586
 587         /* If we didn't detach, allow coredumps */
 588         if(!do_detach)
 589                 sighandlers[3].handler = SIG_DFL;
 590
 591         /* Then, for each known signal that we want to catch, assign a
 592            handler to the signal, with error checking this time. */
 593         for(i = 0; sighandlers[i].signal; i++) {
 594                 act.sa_handler = sighandlers[i].handler;
 595                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 596                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 597                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 598                                         strerror(errno));
 599         }
 600 #endif
 601 }