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 1.1.2.76 2003/10/06 16:13:08 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 #ifdef HAVE_MINGW
  62 extern char *identname;
  63 extern char *program_name;
  64 extern char **g_argv;
  65
  66 static SC_HANDLE manager = NULL;
  67 static SC_HANDLE service = NULL;
  68 static SERVICE_STATUS status = {0};
  69 static SERVICE_STATUS_HANDLE statushandle = 0;
  70
  71 bool install_service(void) {
  72         char command[4096] = "\"";
  73         char **argp;
  74         bool space;
  75         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  76
  77         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  78         if(!manager) {
  79                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  80                 return false;
  81         }
  82
  83         if(!strchr(program_name, '\\')) {
  84                 GetCurrentDirectory(sizeof(command) - 1, command + 1);
  85                 strncat(command, "\\", sizeof(command));
  86         }
  87
  88         strncat(command, program_name, sizeof(command));
  89
  90         strncat(command, "\"", sizeof(command));
  91
  92         for(argp = g_argv + 1; *argp; argp++) {
  93                 space = strchr(*argp, ' ');
  94                 strncat(command, " ", sizeof(command));
  95
  96                 if(space)
  97                         strncat(command, "\"", sizeof(command));
  98
  99                 strncat(command, *argp, sizeof(command));
 100
 101                 if(space)
 102                         strncat(command, "\"", sizeof(command));
 103         }
 104
 105         service = CreateService(manager, identname, identname,
 106                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 107                         command, "NDIS", NULL, NULL, NULL, NULL);
 108
 109         if(!service) {
 110                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 111                 return false;
 112         }
 113
 114         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 115
 116         logger(LOG_INFO, _("%s service installed"), identname);
 117
 118         if(!StartService(service, 0, NULL))
 119                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 120         else
 121                 logger(LOG_INFO, _("%s service started"), identname);
 122
 123         return true;
 124 }
 125
 126 bool remove_service(void) {
 127         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 128         if(!manager) {
 129                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 130                 return false;
 131         }
 132
 133         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 134
 135         if(!service) {
 136                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 137                 return false;
 138         }
 139
 140         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 141                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 142         else
 143                 logger(LOG_INFO, _("%s service stopped"), identname);
 144
 145         if(!DeleteService(service)) {
 146                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 147                 return false;
 148         }
 149
 150         logger(LOG_INFO, _("%s service removed"), identname);
 151
 152         return true;
 153 }
 154
 155 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 156         switch(request) {
 157                 case SERVICE_CONTROL_STOP:
 158                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 159                         break;
 160                 case SERVICE_CONTROL_SHUTDOWN:
 161                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 162                         break;
 163                 default:
 164                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 165                         return ERROR_CALL_NOT_IMPLEMENTED;
 166         }
 167
 168         if(running) {
 169                 running = false;
 170                 status.dwWaitHint = 30000;
 171                 status.dwCurrentState = SERVICE_STOP_PENDING;
 172                 SetServiceStatus(statushandle, &status);
 173                 return NO_ERROR;
 174         } else {
 175                 status.dwWaitHint = 0;
 176                 status.dwCurrentState = SERVICE_STOPPED;
 177                 SetServiceStatus(statushandle, &status);
 178                 exit(1);
 179         }
 180
 181 }
 182
 183 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
 184 {
 185         int err = 1;
 186         extern int main2(int argc, char **argv);
 187
 188
 189         status.dwServiceType = SERVICE_WIN32;
 190         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 191         status.dwWin32ExitCode = 0;
 192         status.dwServiceSpecificExitCode = 0;
 193         status.dwCheckPoint = 0;
 194
 195         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 196
 197         if (!statushandle) {
 198                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 199                 err = 1;
 200         } else {
 201                 status.dwWaitHint = 30000;
 202                 status.dwCurrentState = SERVICE_START_PENDING;
 203                 SetServiceStatus(statushandle, &status);
 204
 205                 status.dwWaitHint = 0;
 206                 status.dwCurrentState = SERVICE_RUNNING;
 207                 SetServiceStatus(statushandle, &status);
 208
 209                 err = main2(argc, argv);
 210
 211                 status.dwWaitHint = 0;
 212                 status.dwCurrentState = SERVICE_STOPPED;
 213                 //status.dwWin32ExitCode = err;
 214                 SetServiceStatus(statushandle, &status);
 215         }
 216
 217         return;
 218 }
 219
 220 bool init_service(void) {
 221         SERVICE_TABLE_ENTRY services[] = {
 222                 {identname, run_service},
 223                 {NULL, NULL}
 224         };
 225
 226         if(!StartServiceCtrlDispatcher(services)) {
 227                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 228                         return false;
 229                 }
 230                 else
 231                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 232         }
 233
 234         return true;
 235 }
 236 #endif
 237
 238 #ifndef HAVE_MINGW
 239 /*
 240   check for an existing tinc for this net, and write pid to pidfile
 241 */
 242 static bool write_pidfile(void)
 243 {
 244         pid_t pid;
 245
 246         cp();
 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                 return false;
 262
 263         return true;
 264 }
 265 #endif
 266
 267 /*
 268   kill older tincd for this net
 269 */
 270 bool kill_other(int signal)
 271 {
 272 #ifndef HAVE_MINGW
 273         pid_t pid;
 274
 275         cp();
 276
 277         pid = read_pid(pidfilename);
 278
 279         if(!pid) {
 280                 if(netname)
 281                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 282                                         netname);
 283                 else
 284                         fprintf(stderr, _("No other tincd is running.\n"));
 285                 return false;
 286         }
 287
 288         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 289
 290         /* ESRCH is returned when no process with that pid is found */
 291         if(kill(pid, signal) && errno == ESRCH) {
 292                 if(netname)
 293                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 294                                         netname);
 295                 else
 296                         fprintf(stderr, _("The tincd is no longer running. "));
 297
 298                 fprintf(stderr, _("Removing stale lock file.\n"));
 299                 remove_pid(pidfilename);
 300         }
 301
 302         return true;
 303 #else
 304         return remove_service();
 305 #endif
 306 }
 307
 308 /*
 309   Detach from current terminal, write pidfile, kill parent
 310 */
 311 bool detach(void)
 312 {
 313         cp();
 314
 315         setup_signals();
 316
 317         /* First check if we can open a fresh new pidfile */
 318
 319 #ifndef HAVE_MINGW
 320         if(!write_pidfile())
 321                 return false;
 322
 323         /* If we succeeded in doing that, detach */
 324
 325         closelogger();
 326 #endif
 327
 328         if(do_detach) {
 329 #ifndef HAVE_MINGW
 330                 if(daemon(0, 0)) {
 331                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 332                                         strerror(errno));
 333                         return false;
 334                 }
 335
 336                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 337
 338                 if(!write_pid(pidfilename))
 339                         return false;
 340 #else
 341                 if(!statushandle)
 342                         exit(install_service());
 343 #endif
 344         }
 345
 346         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 347
 348         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 349                            VERSION, __DATE__, __TIME__, debug_level);
 350
 351         xalloc_fail_func = memory_full;
 352
 353         return true;
 354 }
 355
 356 bool execute_script(const char *name, char **envp)
 357 {
 358 #ifdef HAVE_SYSTEM
 359         int status, len;
 360         struct stat s;
 361         char *scriptname;
 362
 363         cp();
 364
 365 #ifndef HAVE_MINGW
 366         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 367 #else
 368         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 369 #endif
 370         if(len < 0)
 371                 return false;
 372
 373         scriptname[len - 1] = '\0';
 374
 375         /* First check if there is a script */
 376
 377         if(stat(scriptname + 1, &s))
 378                 return true;
 379
 380         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 381
 382 #ifdef HAVE_PUTENV
 383         /* Set environment */
 384
 385         while(*envp)
 386                 putenv(*envp++);
 387 #endif
 388
 389         scriptname[len - 1] = '\"';
 390         status = system(scriptname);
 391
 392         free(scriptname);
 393
 394         /* Unset environment? */
 395
 396 #ifdef WEXITSTATUS
 397         if(status != -1) {
 398                 if(WIFEXITED(status)) { /* Child exited by itself */
 399                         if(WEXITSTATUS(status)) {
 400                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 401                                            name, WEXITSTATUS(status));
 402                                 return false;
 403                         }
 404                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 405                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 406                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 407                         return false;
 408                 } else {                        /* Something strange happened */
 409                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 410                         return false;
 411                 }
 412         } else {
 413                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 414                 return false;
 415         }
 416 #endif
 417 #endif
 418         return true;
 419 }
 420
 421
 422 /*
 423   Signal handlers.
 424 */
 425
 426 #ifndef HAVE_MINGW
 427 static RETSIGTYPE sigterm_handler(int a)
 428 {
 429         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 430         running = false;
 431 }
 432
 433 static RETSIGTYPE sigquit_handler(int a)
 434 {
 435         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 436         running = false;
 437 }
 438
 439 static RETSIGTYPE fatal_signal_square(int a)
 440 {
 441         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 442                    strsignal(a));
 443         cp_trace();
 444         exit(1);
 445 }
 446
 447 static RETSIGTYPE fatal_signal_handler(int a)
 448 {
 449         struct sigaction act;
 450         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 451         cp_trace();
 452
 453         if(do_detach) {
 454                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 455
 456                 act.sa_handler = fatal_signal_square;
 457                 act.sa_mask = emptysigset;
 458                 act.sa_flags = 0;
 459                 sigaction(SIGSEGV, &act, NULL);
 460
 461                 close_network_connections();
 462                 sleep(5);
 463                 remove_pid(pidfilename);
 464                 execvp(g_argv[0], g_argv);
 465         } else {
 466                 logger(LOG_NOTICE, _("Not restarting."));
 467                 exit(1);
 468         }
 469 }
 470
 471 static RETSIGTYPE sighup_handler(int a)
 472 {
 473         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 474         sighup = true;
 475 }
 476
 477 static RETSIGTYPE sigint_handler(int a)
 478 {
 479         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 480
 481         if(saved_debug_level != -1) {
 482                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 483                         saved_debug_level);
 484                 debug_level = saved_debug_level;
 485                 saved_debug_level = -1;
 486         } else {
 487                 logger(LOG_NOTICE,
 488                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 489                         debug_level);
 490                 saved_debug_level = debug_level;
 491                 debug_level = 5;
 492         }
 493 }
 494
 495 static RETSIGTYPE sigalrm_handler(int a)
 496 {
 497         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 498         sigalrm = true;
 499 }
 500
 501 static RETSIGTYPE sigusr1_handler(int a)
 502 {
 503         dump_connections();
 504 }
 505
 506 static RETSIGTYPE sigusr2_handler(int a)
 507 {
 508         dump_device_stats();
 509         dump_nodes();
 510         dump_edges();
 511         dump_subnets();
 512 }
 513
 514 static RETSIGTYPE sigwinch_handler(int a)
 515 {
 516         do_purge = true;
 517 }
 518
 519 static RETSIGTYPE unexpected_signal_handler(int a)
 520 {
 521         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 522         cp_trace();
 523 }
 524
 525 static RETSIGTYPE ignore_signal_handler(int a)
 526 {
 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 {
 553 #ifndef HAVE_MINGW
 554         int i;
 555         struct sigaction act;
 556
 557         sigemptyset(&emptysigset);
 558         act.sa_handler = NULL;
 559         act.sa_mask = emptysigset;
 560         act.sa_flags = 0;
 561
 562         /* Set a default signal handler for every signal, errors will be
 563            ignored. */
 564         for(i = 0; i < NSIG; i++) {
 565                 if(!do_detach)
 566                         act.sa_handler = SIG_DFL;
 567                 else
 568                         act.sa_handler = unexpected_signal_handler;
 569                 sigaction(i, &act, NULL);
 570         }
 571
 572         /* If we didn't detach, allow coredumps */
 573         if(!do_detach)
 574                 sighandlers[3].handler = SIG_DFL;
 575
 576         /* Then, for each known signal that we want to catch, assign a
 577            handler to the signal, with error checking this time. */
 578         for(i = 0; sighandlers[i].signal; i++) {
 579                 act.sa_handler = sighandlers[i].handler;
 580                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 581                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 582                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 583                                         strerror(errno));
 584         }
 585 #endif
 586 }