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

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2004 Ivo Timmermans <ivo@tinc-vpn.org>,
   4                   2000-2004 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     $Id$
  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                 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 {
 274 #ifndef HAVE_MINGW
 275         pid_t pid;
 276
 277         cp();
 278
 279         pid = read_pid(pidfilename);
 280
 281         if(!pid) {
 282                 if(netname)
 283                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 284                                         netname);
 285                 else
 286                         fprintf(stderr, _("No other tincd is running.\n"));
 287                 return false;
 288         }
 289
 290         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 291
 292         /* ESRCH is returned when no process with that pid is found */
 293         if(kill(pid, signal) && errno == ESRCH) {
 294                 if(netname)
 295                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 296                                         netname);
 297                 else
 298                         fprintf(stderr, _("The tincd is no longer running. "));
 299
 300                 fprintf(stderr, _("Removing stale lock file.\n"));
 301                 remove_pid(pidfilename);
 302         }
 303
 304         return true;
 305 #else
 306         return remove_service();
 307 #endif
 308 }
 309
 310 /*
 311   Detach from current terminal, write pidfile, kill parent
 312 */
 313 bool detach(void)
 314 {
 315         cp();
 316
 317         setup_signals();
 318
 319         /* First check if we can open a fresh new pidfile */
 320
 321 #ifndef HAVE_MINGW
 322         if(!write_pidfile())
 323                 return false;
 324
 325         /* If we succeeded in doing that, detach */
 326
 327         closelogger();
 328 #endif
 329
 330         if(do_detach) {
 331 #ifndef HAVE_MINGW
 332                 if(daemon(0, 0)) {
 333                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 334                                         strerror(errno));
 335                         return false;
 336                 }
 337
 338                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 339
 340                 if(!write_pid(pidfilename)) {
 341                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 342                         return false;
 343                 }
 344 #else
 345                 if(!statushandle)
 346                         exit(install_service());
 347 #endif
 348         }
 349
 350         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 351
 352         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 353                            VERSION, __DATE__, __TIME__, debug_level);
 354
 355         xalloc_fail_func = memory_full;
 356
 357         return true;
 358 }
 359
 360 bool execute_script(const char *name, char **envp)
 361 {
 362 #ifdef HAVE_SYSTEM
 363         int status, len;
 364         struct stat s;
 365         char *scriptname;
 366         int i;
 367
 368         cp();
 369
 370 #ifndef HAVE_MINGW
 371         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 372 #else
 373         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 374 #endif
 375         if(len < 0)
 376                 return false;
 377
 378         scriptname[len - 1] = '\0';
 379
 380         /* First check if there is a script */
 381
 382         if(stat(scriptname + 1, &s))
 383                 return true;
 384
 385         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 386
 387 #ifdef HAVE_PUTENV
 388         /* Set environment */
 389
 390         for(i = 0; envp[i]; i++)
 391                 putenv(envp[i]);
 392 #endif
 393
 394         scriptname[len - 1] = '\"';
 395         status = system(scriptname);
 396
 397         free(scriptname);
 398
 399         /* Unset environment */
 400
 401         for(i = 0; envp[i]; i++) {
 402                 char *e = strchr(envp[i], '=');
 403                 if(e)
 404                         putenv(strndupa(envp[i], e - envp[i]));
 405         }
 406
 407 #ifdef WEXITSTATUS
 408         if(status != -1) {
 409                 if(WIFEXITED(status)) { /* Child exited by itself */
 410                         if(WEXITSTATUS(status)) {
 411                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 412                                            name, WEXITSTATUS(status));
 413                                 return false;
 414                         }
 415                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 416                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 417                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 418                         return false;
 419                 } else {                        /* Something strange happened */
 420                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 421                         return false;
 422                 }
 423         } else {
 424                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 425                 return false;
 426         }
 427 #endif
 428 #endif
 429         return true;
 430 }
 431
 432
 433 /*
 434   Signal handlers.
 435 */
 436
 437 #ifndef HAVE_MINGW
 438 static RETSIGTYPE sigterm_handler(int a)
 439 {
 440         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 441         if(running)
 442                 running = false;
 443         else
 444                 exit(1);
 445 }
 446
 447 static RETSIGTYPE sigquit_handler(int a)
 448 {
 449         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 450         if(running)
 451                 running = false;
 452         else
 453                 exit(1);
 454 }
 455
 456 static RETSIGTYPE fatal_signal_square(int a)
 457 {
 458         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 459                    strsignal(a));
 460         cp_trace();
 461         exit(1);
 462 }
 463
 464 static RETSIGTYPE fatal_signal_handler(int a)
 465 {
 466         struct sigaction act;
 467         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 468         cp_trace();
 469
 470         if(do_detach) {
 471                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 472
 473                 act.sa_handler = fatal_signal_square;
 474                 act.sa_mask = emptysigset;
 475                 act.sa_flags = 0;
 476                 sigaction(SIGSEGV, &act, NULL);
 477
 478                 close_network_connections();
 479                 sleep(5);
 480                 remove_pid(pidfilename);
 481                 execvp(g_argv[0], g_argv);
 482         } else {
 483                 logger(LOG_NOTICE, _("Not restarting."));
 484                 exit(1);
 485         }
 486 }
 487
 488 static RETSIGTYPE sighup_handler(int a)
 489 {
 490         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 491         sighup = true;
 492 }
 493
 494 static RETSIGTYPE sigint_handler(int a)
 495 {
 496         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 497
 498         if(saved_debug_level != -1) {
 499                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 500                         saved_debug_level);
 501                 debug_level = saved_debug_level;
 502                 saved_debug_level = -1;
 503         } else {
 504                 logger(LOG_NOTICE,
 505                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 506                         debug_level);
 507                 saved_debug_level = debug_level;
 508                 debug_level = 5;
 509         }
 510 }
 511
 512 static RETSIGTYPE sigalrm_handler(int a)
 513 {
 514         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 515         sigalrm = true;
 516 }
 517
 518 static RETSIGTYPE sigusr1_handler(int a)
 519 {
 520         dump_connections();
 521 }
 522
 523 static RETSIGTYPE sigusr2_handler(int a)
 524 {
 525         dump_device_stats();
 526         dump_nodes();
 527         dump_edges();
 528         dump_subnets();
 529 }
 530
 531 static RETSIGTYPE sigwinch_handler(int a)
 532 {
 533         do_purge = true;
 534 }
 535
 536 static RETSIGTYPE unexpected_signal_handler(int a)
 537 {
 538         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 539         cp_trace();
 540 }
 541
 542 static RETSIGTYPE ignore_signal_handler(int a)
 543 {
 544         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 545 }
 546
 547 static struct {
 548         int signal;
 549         void (*handler)(int);
 550 } sighandlers[] = {
 551         {SIGHUP, sighup_handler},
 552         {SIGTERM, sigterm_handler},
 553         {SIGQUIT, sigquit_handler},
 554         {SIGSEGV, fatal_signal_handler},
 555         {SIGBUS, fatal_signal_handler},
 556         {SIGILL, fatal_signal_handler},
 557         {SIGPIPE, ignore_signal_handler},
 558         {SIGINT, sigint_handler},
 559         {SIGUSR1, sigusr1_handler},
 560         {SIGUSR2, sigusr2_handler},
 561         {SIGCHLD, ignore_signal_handler},
 562         {SIGALRM, sigalrm_handler},
 563         {SIGWINCH, sigwinch_handler},
 564         {0, NULL}
 565 };
 566 #endif
 567
 568 void setup_signals(void)
 569 {
 570 #ifndef HAVE_MINGW
 571         int i;
 572         struct sigaction act;
 573
 574         sigemptyset(&emptysigset);
 575         act.sa_handler = NULL;
 576         act.sa_mask = emptysigset;
 577         act.sa_flags = 0;
 578
 579         /* Set a default signal handler for every signal, errors will be
 580            ignored. */
 581         for(i = 0; i < NSIG; i++) {
 582                 if(!do_detach)
 583                         act.sa_handler = SIG_DFL;
 584                 else
 585                         act.sa_handler = unexpected_signal_handler;
 586                 sigaction(i, &act, NULL);
 587         }
 588
 589         /* If we didn't detach, allow coredumps */
 590         if(!do_detach)
 591                 sighandlers[3].handler = SIG_DFL;
 592
 593         /* Then, for each known signal that we want to catch, assign a
 594            handler to the signal, with error checking this time. */
 595         for(i = 0; sighandlers[i].signal; i++) {
 596                 act.sa_handler = sighandlers[i].handler;
 597                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 598                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 599                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 600                                         strerror(errno));
 601         }
 602 #endif
 603 }