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
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, 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 {
  52         logger(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size);
  53         cp_trace();
  54         exit(1);
  55 }
  56
  57 /* Some functions the less gifted operating systems might lack... */
  58
  59 #ifdef HAVE_MINGW
  60 extern char *identname;
  61 extern char *program_name;
  62 extern char **g_argv;
  63
  64 static SC_HANDLE manager = NULL;
  65 static SC_HANDLE service = NULL;
  66 static SERVICE_STATUS status = {0};
  67 static SERVICE_STATUS_HANDLE statushandle = 0;
  68
  69 bool install_service(void) {
  70         char command[4096] = "\"";
  71         char **argp;
  72         bool space;
  73         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  74
  75         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  76         if(!manager) {
  77                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  78                 return false;
  79         }
  80
  81         if(!strchr(program_name, '\\')) {
  82                 GetCurrentDirectory(sizeof command - 1, command + 1);
  83                 strncat(command, "\\", sizeof command - strlen(command));
  84         }
  85
  86         strncat(command, program_name, sizeof command - strlen(command));
  87
  88         strncat(command, "\"", sizeof command - strlen(command));
  89
  90         for(argp = g_argv + 1; *argp; argp++) {
  91                 space = strchr(*argp, ' ');
  92                 strncat(command, " ", sizeof command - strlen(command));
  93
  94                 if(space)
  95                         strncat(command, "\"", sizeof command - strlen(command));
  96
  97                 strncat(command, *argp, sizeof command - strlen(command));
  98
  99                 if(space)
 100                         strncat(command, "\"", sizeof command - strlen(command));
 101         }
 102
 103         service = CreateService(manager, identname, identname,
 104                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 105                         command, NULL, NULL, NULL, NULL, NULL);
 106
 107         if(!service) {
 108                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 109                 return false;
 110         }
 111
 112         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 113
 114         logger(LOG_INFO, _("%s service installed"), identname);
 115
 116         if(!StartService(service, 0, NULL))
 117                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 118         else
 119                 logger(LOG_INFO, _("%s service started"), identname);
 120
 121         return true;
 122 }
 123
 124 bool remove_service(void) {
 125         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 126         if(!manager) {
 127                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 128                 return false;
 129         }
 130
 131         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 132
 133         if(!service) {
 134                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 135                 return false;
 136         }
 137
 138         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 139                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 140         else
 141                 logger(LOG_INFO, _("%s service stopped"), identname);
 142
 143         if(!DeleteService(service)) {
 144                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 145                 return false;
 146         }
 147
 148         logger(LOG_INFO, _("%s service removed"), identname);
 149
 150         return true;
 151 }
 152
 153 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 154         switch(request) {
 155                 case SERVICE_CONTROL_INTERROGATE:
 156                         SetServiceStatus(statushandle, &status);
 157                         return NO_ERROR;
 158                 case SERVICE_CONTROL_STOP:
 159                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 160                         break;
 161                 case SERVICE_CONTROL_SHUTDOWN:
 162                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 163                         break;
 164                 default:
 165                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 166                         return ERROR_CALL_NOT_IMPLEMENTED;
 167         }
 168
 169         if(running) {
 170                 running = false;
 171                 status.dwWaitHint = 30000;
 172                 status.dwCurrentState = SERVICE_STOP_PENDING;
 173                 SetServiceStatus(statushandle, &status);
 174                 return NO_ERROR;
 175         } else {
 176                 status.dwWaitHint = 0;
 177                 status.dwCurrentState = SERVICE_STOPPED;
 178                 SetServiceStatus(statushandle, &status);
 179                 exit(1);
 180         }
 181
 182 }
 183
 184 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
 185 {
 186         int err = 1;
 187         extern int main2(int argc, char **argv);
 188
 189
 190         status.dwServiceType = SERVICE_WIN32;
 191         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 192         status.dwWin32ExitCode = 0;
 193         status.dwServiceSpecificExitCode = 0;
 194         status.dwCheckPoint = 0;
 195
 196         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 197
 198         if (!statushandle) {
 199                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 200                 err = 1;
 201         } else {
 202                 status.dwWaitHint = 30000;
 203                 status.dwCurrentState = SERVICE_START_PENDING;
 204                 SetServiceStatus(statushandle, &status);
 205
 206                 status.dwWaitHint = 0;
 207                 status.dwCurrentState = SERVICE_RUNNING;
 208                 SetServiceStatus(statushandle, &status);
 209
 210                 err = main2(argc, argv);
 211
 212                 status.dwWaitHint = 0;
 213                 status.dwCurrentState = SERVICE_STOPPED;
 214                 //status.dwWin32ExitCode = err;
 215                 SetServiceStatus(statushandle, &status);
 216         }
 217
 218         return;
 219 }
 220
 221 bool init_service(void) {
 222         SERVICE_TABLE_ENTRY services[] = {
 223                 {identname, run_service},
 224                 {NULL, NULL}
 225         };
 226
 227         if(!StartServiceCtrlDispatcher(services)) {
 228                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 229                         return false;
 230                 }
 231                 else
 232                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 233         }
 234
 235         return true;
 236 }
 237 #endif
 238
 239 #ifndef HAVE_MINGW
 240 /*
 241   check for an existing tinc for this net, and write pid to pidfile
 242 */
 243 static bool write_pidfile(void)
 244 {
 245         pid_t pid;
 246
 247         cp();
 248
 249         pid = check_pid(pidfilename);
 250
 251         if(pid) {
 252                 if(netname)
 253                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 254                                         netname, (long)pid);
 255                 else
 256                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 257                 return false;
 258         }
 259
 260         /* if it's locked, write-protected, or whatever */
 261         if(!write_pid(pidfilename)) {
 262                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 263                 return false;
 264         }
 265
 266         return true;
 267 }
 268 #endif
 269
 270 /*
 271   kill older tincd for this net
 272 */
 273 bool kill_other(int signal)
 274 {
 275 #ifndef HAVE_MINGW
 276         pid_t pid;
 277
 278         cp();
 279
 280         pid = read_pid(pidfilename);
 281
 282         if(!pid) {
 283                 if(netname)
 284                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 285                                         netname);
 286                 else
 287                         fprintf(stderr, _("No other tincd is running.\n"));
 288                 return false;
 289         }
 290
 291         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 292
 293         /* ESRCH is returned when no process with that pid is found */
 294         if(kill(pid, signal) && errno == ESRCH) {
 295                 if(netname)
 296                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 297                                         netname);
 298                 else
 299                         fprintf(stderr, _("The tincd is no longer running. "));
 300
 301                 fprintf(stderr, _("Removing stale lock file.\n"));
 302                 remove_pid(pidfilename);
 303         }
 304
 305         return true;
 306 #else
 307         return remove_service();
 308 #endif
 309 }
 310
 311 /*
 312   Detach from current terminal, write pidfile, kill parent
 313 */
 314 bool detach(void)
 315 {
 316         cp();
 317
 318         setup_signals();
 319
 320         /* First check if we can open a fresh new pidfile */
 321
 322 #ifndef HAVE_MINGW
 323         if(!write_pidfile())
 324                 return false;
 325
 326         /* If we succeeded in doing that, detach */
 327
 328         closelogger();
 329 #endif
 330
 331         if(do_detach) {
 332 #ifndef HAVE_MINGW
 333                 if(daemon(0, 0)) {
 334                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 335                                         strerror(errno));
 336                         return false;
 337                 }
 338
 339                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 340
 341                 if(!write_pid(pidfilename)) {
 342                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 343                         return false;
 344                 }
 345 #else
 346                 if(!statushandle)
 347                         exit(install_service());
 348 #endif
 349         }
 350
 351         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 352
 353         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 354                            VERSION, __DATE__, __TIME__, debug_level);
 355
 356         xalloc_fail_func = memory_full;
 357
 358         return true;
 359 }
 360
 361 bool execute_script(const char *name, char **envp)
 362 {
 363 #ifdef HAVE_SYSTEM
 364         int status, len;
 365         char *scriptname, *p;
 366         int i;
 367
 368         cp();
 369
 370 #ifndef HAVE_MINGW
 371         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 372 #else
 373         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 374 #endif
 375         if(len < 0)
 376                 return false;
 377
 378         scriptname[len - 1] = '\0';
 379
 380 #ifndef HAVE_TUNEMU
 381         /* First check if there is a script */
 382
 383         if(access(scriptname + 1, F_OK)) {
 384                 free(scriptname);
 385                 return true;
 386         }
 387 #endif
 388
 389         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 390
 391 #ifdef HAVE_PUTENV
 392         /* Set environment */
 393
 394         for(i = 0; envp[i]; i++)
 395                 putenv(envp[i]);
 396 #endif
 397
 398         scriptname[len - 1] = '\"';
 399         status = system(scriptname);
 400
 401         free(scriptname);
 402
 403         /* Unset environment */
 404
 405         for(i = 0; envp[i]; i++) {
 406                 char *e = strchr(envp[i], '=');
 407                 if(e) {
 408                         p = alloca(e - envp[i] + 1);
 409                         strncpy(p, envp[i], e - envp[i]);
 410                         p[e - envp[i]] = '\0';
 411                         putenv(p);
 412                 }
 413         }
 414
 415 #ifdef WEXITSTATUS
 416         if(status != -1) {
 417                 if(WIFEXITED(status)) { /* Child exited by itself */
 418                         if(WEXITSTATUS(status)) {
 419                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 420                                            name, WEXITSTATUS(status));
 421                                 return false;
 422                         }
 423                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 424                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 425                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 426                         return false;
 427                 } else {                        /* Something strange happened */
 428                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 429                         return false;
 430                 }
 431         } else {
 432                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 433                 return false;
 434         }
 435 #endif
 436 #endif
 437         return true;
 438 }
 439
 440
 441 /*
 442   Signal handlers.
 443 */
 444
 445 #ifndef HAVE_MINGW
 446 static RETSIGTYPE sigterm_handler(int a)
 447 {
 448         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 449         if(running)
 450                 running = false;
 451         else
 452                 exit(1);
 453 }
 454
 455 static RETSIGTYPE sigquit_handler(int a)
 456 {
 457         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 458         if(running)
 459                 running = false;
 460         else
 461                 exit(1);
 462 }
 463
 464 static RETSIGTYPE fatal_signal_square(int a)
 465 {
 466         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 467                    strsignal(a));
 468         cp_trace();
 469         exit(1);
 470 }
 471
 472 static RETSIGTYPE fatal_signal_handler(int a)
 473 {
 474         struct sigaction act;
 475         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 476         cp_trace();
 477
 478         if(do_detach) {
 479                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 480
 481                 act.sa_handler = fatal_signal_square;
 482                 act.sa_mask = emptysigset;
 483                 act.sa_flags = 0;
 484                 sigaction(SIGSEGV, &act, NULL);
 485
 486                 close_network_connections();
 487                 sleep(5);
 488                 remove_pid(pidfilename);
 489                 execvp(g_argv[0], g_argv);
 490         } else {
 491                 logger(LOG_NOTICE, _("Not restarting."));
 492                 exit(1);
 493         }
 494 }
 495
 496 static RETSIGTYPE sighup_handler(int a)
 497 {
 498         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 499         sighup = true;
 500 }
 501
 502 static RETSIGTYPE sigint_handler(int a)
 503 {
 504         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 505
 506         if(saved_debug_level != -1) {
 507                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 508                         saved_debug_level);
 509                 debug_level = saved_debug_level;
 510                 saved_debug_level = -1;
 511         } else {
 512                 logger(LOG_NOTICE,
 513                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 514                         debug_level);
 515                 saved_debug_level = debug_level;
 516                 debug_level = 5;
 517         }
 518 }
 519
 520 static RETSIGTYPE sigalrm_handler(int a)
 521 {
 522         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 523         sigalrm = true;
 524 }
 525
 526 static RETSIGTYPE sigusr1_handler(int a)
 527 {
 528         dump_connections();
 529 }
 530
 531 static RETSIGTYPE sigusr2_handler(int a)
 532 {
 533         dump_device_stats();
 534         dump_nodes();
 535         dump_edges();
 536         dump_subnets();
 537 }
 538
 539 static RETSIGTYPE sigwinch_handler(int a)
 540 {
 541         do_purge = true;
 542 }
 543
 544 static RETSIGTYPE unexpected_signal_handler(int a)
 545 {
 546         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 547         cp_trace();
 548 }
 549
 550 static RETSIGTYPE ignore_signal_handler(int a)
 551 {
 552         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 553 }
 554
 555 static struct {
 556         int signal;
 557         void (*handler)(int);
 558 } sighandlers[] = {
 559         {SIGHUP, sighup_handler},
 560         {SIGTERM, sigterm_handler},
 561         {SIGQUIT, sigquit_handler},
 562         {SIGSEGV, fatal_signal_handler},
 563         {SIGBUS, fatal_signal_handler},
 564         {SIGILL, fatal_signal_handler},
 565         {SIGPIPE, ignore_signal_handler},
 566         {SIGINT, sigint_handler},
 567         {SIGUSR1, sigusr1_handler},
 568         {SIGUSR2, sigusr2_handler},
 569         {SIGCHLD, ignore_signal_handler},
 570         {SIGALRM, sigalrm_handler},
 571         {SIGWINCH, sigwinch_handler},
 572         {0, NULL}
 573 };
 574 #endif
 575
 576 void setup_signals(void)
 577 {
 578 #ifndef HAVE_MINGW
 579         int i;
 580         struct sigaction act;
 581
 582         sigemptyset(&emptysigset);
 583         act.sa_handler = NULL;
 584         act.sa_mask = emptysigset;
 585         act.sa_flags = 0;
 586
 587         /* Set a default signal handler for every signal, errors will be
 588            ignored. */
 589         for(i = 1; i < NSIG; i++) {
 590                 if(!do_detach)
 591                         act.sa_handler = SIG_DFL;
 592                 else
 593                         act.sa_handler = unexpected_signal_handler;
 594                 sigaction(i, &act, NULL);
 595         }
 596
 597         /* If we didn't detach, allow coredumps */
 598         if(!do_detach)
 599                 sighandlers[3].handler = SIG_DFL;
 600
 601         /* Then, for each known signal that we want to catch, assign a
 602            handler to the signal, with error checking this time. */
 603         for(i = 0; sighandlers[i].signal; i++) {
 604                 act.sa_handler = sighandlers[i].handler;
 605                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 606                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 607                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 608                                         strerror(errno));
 609         }
 610 #endif
 611 }