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

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2005 Ivo Timmermans,
   4                   2000-2006 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 - strlen(command));
  86         }
  87
  88         strncat(command, program_name, sizeof command - strlen(command));
  89
  90         strncat(command, "\"", sizeof command - strlen(command));
  91
  92         for(argp = g_argv + 1; *argp; argp++) {
  93                 space = strchr(*argp, ' ');
  94                 strncat(command, " ", sizeof command - strlen(command));
  95
  96                 if(space)
  97                         strncat(command, "\"", sizeof command - strlen(command));
  98
  99                 strncat(command, *argp, sizeof command - strlen(command));
 100
 101                 if(space)
 102                         strncat(command, "\"", sizeof command - strlen(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, NULL, 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_INTERROGATE:
 158                         SetServiceStatus(statushandle, &status);
 159                         return NO_ERROR;
 160                 case SERVICE_CONTROL_STOP:
 161                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 162                         break;
 163                 case SERVICE_CONTROL_SHUTDOWN:
 164                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 165                         break;
 166                 default:
 167                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 168                         return ERROR_CALL_NOT_IMPLEMENTED;
 169         }
 170
 171         if(running) {
 172                 running = false;
 173                 status.dwWaitHint = 30000;
 174                 status.dwCurrentState = SERVICE_STOP_PENDING;
 175                 SetServiceStatus(statushandle, &status);
 176                 return NO_ERROR;
 177         } else {
 178                 status.dwWaitHint = 0;
 179                 status.dwCurrentState = SERVICE_STOPPED;
 180                 SetServiceStatus(statushandle, &status);
 181                 exit(1);
 182         }
 183
 184 }
 185
 186 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
 187 {
 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 {
 247         pid_t pid;
 248
 249         cp();
 250
 251         pid = check_pid(pidfilename);
 252
 253         if(pid) {
 254                 if(netname)
 255                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 256                                         netname, (long)pid);
 257                 else
 258                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 259                 return false;
 260         }
 261
 262         /* if it's locked, write-protected, or whatever */
 263         if(!write_pid(pidfilename)) {
 264                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 265                 return false;
 266         }
 267
 268         return true;
 269 }
 270 #endif
 271
 272 /*
 273   kill older tincd for this net
 274 */
 275 bool kill_other(int signal)
 276 {
 277 #ifndef HAVE_MINGW
 278         pid_t pid;
 279
 280         cp();
 281
 282         pid = read_pid(pidfilename);
 283
 284         if(!pid) {
 285                 if(netname)
 286                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 287                                         netname);
 288                 else
 289                         fprintf(stderr, _("No other tincd is running.\n"));
 290                 return false;
 291         }
 292
 293         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 294
 295         /* ESRCH is returned when no process with that pid is found */
 296         if(kill(pid, signal) && errno == ESRCH) {
 297                 if(netname)
 298                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 299                                         netname);
 300                 else
 301                         fprintf(stderr, _("The tincd is no longer running. "));
 302
 303                 fprintf(stderr, _("Removing stale lock file.\n"));
 304                 remove_pid(pidfilename);
 305         }
 306
 307         return true;
 308 #else
 309         return remove_service();
 310 #endif
 311 }
 312
 313 /*
 314   Detach from current terminal, write pidfile, kill parent
 315 */
 316 bool detach(void)
 317 {
 318         cp();
 319
 320         setup_signals();
 321
 322         /* First check if we can open a fresh new pidfile */
 323
 324 #ifndef HAVE_MINGW
 325         if(!write_pidfile())
 326                 return false;
 327
 328         /* If we succeeded in doing that, detach */
 329
 330         closelogger();
 331 #endif
 332
 333         if(do_detach) {
 334 #ifndef HAVE_MINGW
 335                 if(daemon(0, 0)) {
 336                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 337                                         strerror(errno));
 338                         return false;
 339                 }
 340
 341                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 342
 343                 if(!write_pid(pidfilename)) {
 344                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 345                         return false;
 346                 }
 347 #else
 348                 if(!statushandle)
 349                         exit(install_service());
 350 #endif
 351         }
 352
 353         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 354
 355         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 356                            VERSION, __DATE__, __TIME__, debug_level);
 357
 358         xalloc_fail_func = memory_full;
 359
 360         return true;
 361 }
 362
 363 bool execute_script(const char *name, char **envp)
 364 {
 365 #ifdef HAVE_SYSTEM
 366         int status, len;
 367         struct stat s;
 368         char *scriptname, *p;
 369         int i;
 370
 371         cp();
 372
 373 #ifndef HAVE_MINGW
 374         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 375 #else
 376         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 377 #endif
 378         if(len < 0)
 379                 return false;
 380
 381         scriptname[len - 1] = '\0';
 382
 383         /* First check if there is a script */
 384
 385         if(stat(scriptname + 1, &s)) {
 386                 free(scriptname);
 387                 return true;
 388         }
 389
 390         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 391
 392 #ifdef HAVE_PUTENV
 393         /* Set environment */
 394
 395         for(i = 0; envp[i]; i++)
 396                 putenv(envp[i]);
 397 #endif
 398
 399         scriptname[len - 1] = '\"';
 400         status = system(scriptname);
 401
 402         free(scriptname);
 403
 404         /* Unset environment */
 405
 406         for(i = 0; envp[i]; i++) {
 407                 char *e = strchr(envp[i], '=');
 408                 if(e) {
 409                         p = alloca(e - envp[i] + 1);
 410                         strncpy(p, envp[i], e - envp[i]);
 411                         p[e - envp[i]] = '\0';
 412                         putenv(p);
 413                 }
 414         }
 415
 416 #ifdef WEXITSTATUS
 417         if(status != -1) {
 418                 if(WIFEXITED(status)) { /* Child exited by itself */
 419                         if(WEXITSTATUS(status)) {
 420                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 421                                            name, WEXITSTATUS(status));
 422                                 return false;
 423                         }
 424                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 425                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 426                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 427                         return false;
 428                 } else {                        /* Something strange happened */
 429                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 430                         return false;
 431                 }
 432         } else {
 433                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 434                 return false;
 435         }
 436 #endif
 437 #endif
 438         return true;
 439 }
 440
 441
 442 /*
 443   Signal handlers.
 444 */
 445
 446 #ifndef HAVE_MINGW
 447 static RETSIGTYPE sigterm_handler(int a)
 448 {
 449         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 450         if(running)
 451                 running = false;
 452         else
 453                 exit(1);
 454 }
 455
 456 static RETSIGTYPE sigquit_handler(int a)
 457 {
 458         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 459         if(running)
 460                 running = false;
 461         else
 462                 exit(1);
 463 }
 464
 465 static RETSIGTYPE fatal_signal_square(int a)
 466 {
 467         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 468                    strsignal(a));
 469         cp_trace();
 470         exit(1);
 471 }
 472
 473 static RETSIGTYPE fatal_signal_handler(int a)
 474 {
 475         struct sigaction act;
 476         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 477         cp_trace();
 478
 479         if(do_detach) {
 480                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 481
 482                 act.sa_handler = fatal_signal_square;
 483                 act.sa_mask = emptysigset;
 484                 act.sa_flags = 0;
 485                 sigaction(SIGSEGV, &act, NULL);
 486
 487                 close_network_connections();
 488                 sleep(5);
 489                 remove_pid(pidfilename);
 490                 execvp(g_argv[0], g_argv);
 491         } else {
 492                 logger(LOG_NOTICE, _("Not restarting."));
 493                 exit(1);
 494         }
 495 }
 496
 497 static RETSIGTYPE sighup_handler(int a)
 498 {
 499         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 500         sighup = true;
 501 }
 502
 503 static RETSIGTYPE sigint_handler(int a)
 504 {
 505         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 506
 507         if(saved_debug_level != -1) {
 508                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 509                         saved_debug_level);
 510                 debug_level = saved_debug_level;
 511                 saved_debug_level = -1;
 512         } else {
 513                 logger(LOG_NOTICE,
 514                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 515                         debug_level);
 516                 saved_debug_level = debug_level;
 517                 debug_level = 5;
 518         }
 519 }
 520
 521 static RETSIGTYPE sigalrm_handler(int a)
 522 {
 523         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 524         sigalrm = true;
 525 }
 526
 527 static RETSIGTYPE sigusr1_handler(int a)
 528 {
 529         dump_connections();
 530 }
 531
 532 static RETSIGTYPE sigusr2_handler(int a)
 533 {
 534         dump_device_stats();
 535         dump_nodes();
 536         dump_edges();
 537         dump_subnets();
 538 }
 539
 540 static RETSIGTYPE sigwinch_handler(int a)
 541 {
 542         do_purge = true;
 543 }
 544
 545 static RETSIGTYPE unexpected_signal_handler(int a)
 546 {
 547         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 548         cp_trace();
 549 }
 550
 551 static RETSIGTYPE ignore_signal_handler(int a)
 552 {
 553         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 554 }
 555
 556 static struct {
 557         int signal;
 558         void (*handler)(int);
 559 } sighandlers[] = {
 560         {SIGHUP, sighup_handler},
 561         {SIGTERM, sigterm_handler},
 562         {SIGQUIT, sigquit_handler},
 563         {SIGSEGV, fatal_signal_handler},
 564         {SIGBUS, fatal_signal_handler},
 565         {SIGILL, fatal_signal_handler},
 566         {SIGPIPE, ignore_signal_handler},
 567         {SIGINT, sigint_handler},
 568         {SIGUSR1, sigusr1_handler},
 569         {SIGUSR2, sigusr2_handler},
 570         {SIGCHLD, ignore_signal_handler},
 571         {SIGALRM, sigalrm_handler},
 572         {SIGWINCH, sigwinch_handler},
 573         {0, NULL}
 574 };
 575 #endif
 576
 577 void setup_signals(void)
 578 {
 579 #ifndef HAVE_MINGW
 580         int i;
 581         struct sigaction act;
 582
 583         sigemptyset(&emptysigset);
 584         act.sa_handler = NULL;
 585         act.sa_mask = emptysigset;
 586         act.sa_flags = 0;
 587
 588         /* Set a default signal handler for every signal, errors will be
 589            ignored. */
 590         for(i = 0; i < NSIG; i++) {
 591                 if(!do_detach)
 592                         act.sa_handler = SIG_DFL;
 593                 else
 594                         act.sa_handler = unexpected_signal_handler;
 595                 sigaction(i, &act, NULL);
 596         }
 597
 598         /* If we didn't detach, allow coredumps */
 599         if(!do_detach)
 600                 sighandlers[3].handler = SIG_DFL;
 601
 602         /* Then, for each known signal that we want to catch, assign a
 603            handler to the signal, with error checking this time. */
 604         for(i = 0; sighandlers[i].signal; i++) {
 605                 act.sa_handler = sighandlers[i].handler;
 606                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 607                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 608                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 609                                         strerror(errno));
 610         }
 611 #endif
 612 }