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 1.1.2.77 2003/11/27 23:24:59 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                 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 pidfile %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
 367         cp();
 368
 369 #ifndef HAVE_MINGW
 370         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 371 #else
 372         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 373 #endif
 374         if(len < 0)
 375                 return false;
 376
 377         scriptname[len - 1] = '\0';
 378
 379         /* First check if there is a script */
 380
 381         if(stat(scriptname + 1, &s))
 382                 return true;
 383
 384         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 385
 386 #ifdef HAVE_PUTENV
 387         /* Set environment */
 388
 389         while(*envp)
 390                 putenv(*envp++);
 391 #endif
 392
 393         scriptname[len - 1] = '\"';
 394         status = system(scriptname);
 395
 396         free(scriptname);
 397
 398         /* Unset environment? */
 399
 400 #ifdef WEXITSTATUS
 401         if(status != -1) {
 402                 if(WIFEXITED(status)) { /* Child exited by itself */
 403                         if(WEXITSTATUS(status)) {
 404                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 405                                            name, WEXITSTATUS(status));
 406                                 return false;
 407                         }
 408                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 409                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 410                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 411                         return false;
 412                 } else {                        /* Something strange happened */
 413                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 414                         return false;
 415                 }
 416         } else {
 417                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 418                 return false;
 419         }
 420 #endif
 421 #endif
 422         return true;
 423 }
 424
 425
 426 /*
 427   Signal handlers.
 428 */
 429
 430 #ifndef HAVE_MINGW
 431 static RETSIGTYPE sigterm_handler(int a)
 432 {
 433         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 434         running = false;
 435 }
 436
 437 static RETSIGTYPE sigquit_handler(int a)
 438 {
 439         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
 440         running = false;
 441 }
 442
 443 static RETSIGTYPE fatal_signal_square(int a)
 444 {
 445         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 446                    strsignal(a));
 447         cp_trace();
 448         exit(1);
 449 }
 450
 451 static RETSIGTYPE fatal_signal_handler(int a)
 452 {
 453         struct sigaction act;
 454         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 455         cp_trace();
 456
 457         if(do_detach) {
 458                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 459
 460                 act.sa_handler = fatal_signal_square;
 461                 act.sa_mask = emptysigset;
 462                 act.sa_flags = 0;
 463                 sigaction(SIGSEGV, &act, NULL);
 464
 465                 close_network_connections();
 466                 sleep(5);
 467                 remove_pid(pidfilename);
 468                 execvp(g_argv[0], g_argv);
 469         } else {
 470                 logger(LOG_NOTICE, _("Not restarting."));
 471                 exit(1);
 472         }
 473 }
 474
 475 static RETSIGTYPE sighup_handler(int a)
 476 {
 477         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 478         sighup = true;
 479 }
 480
 481 static RETSIGTYPE sigint_handler(int a)
 482 {
 483         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 484
 485         if(saved_debug_level != -1) {
 486                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 487                         saved_debug_level);
 488                 debug_level = saved_debug_level;
 489                 saved_debug_level = -1;
 490         } else {
 491                 logger(LOG_NOTICE,
 492                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 493                         debug_level);
 494                 saved_debug_level = debug_level;
 495                 debug_level = 5;
 496         }
 497 }
 498
 499 static RETSIGTYPE sigalrm_handler(int a)
 500 {
 501         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 502         sigalrm = true;
 503 }
 504
 505 static RETSIGTYPE sigusr1_handler(int a)
 506 {
 507         dump_connections();
 508 }
 509
 510 static RETSIGTYPE sigusr2_handler(int a)
 511 {
 512         dump_device_stats();
 513         dump_nodes();
 514         dump_edges();
 515         dump_subnets();
 516 }
 517
 518 static RETSIGTYPE sigwinch_handler(int a)
 519 {
 520         do_purge = true;
 521 }
 522
 523 static RETSIGTYPE unexpected_signal_handler(int a)
 524 {
 525         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 526         cp_trace();
 527 }
 528
 529 static RETSIGTYPE ignore_signal_handler(int a)
 530 {
 531         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 532 }
 533
 534 static struct {
 535         int signal;
 536         void (*handler)(int);
 537 } sighandlers[] = {
 538         {SIGHUP, sighup_handler},
 539         {SIGTERM, sigterm_handler},
 540         {SIGQUIT, sigquit_handler},
 541         {SIGSEGV, fatal_signal_handler},
 542         {SIGBUS, fatal_signal_handler},
 543         {SIGILL, fatal_signal_handler},
 544         {SIGPIPE, ignore_signal_handler},
 545         {SIGINT, sigint_handler},
 546         {SIGUSR1, sigusr1_handler},
 547         {SIGUSR2, sigusr2_handler},
 548         {SIGCHLD, ignore_signal_handler},
 549         {SIGALRM, sigalrm_handler},
 550         {SIGWINCH, sigwinch_handler},
 551         {0, NULL}
 552 };
 553 #endif
 554
 555 void setup_signals(void)
 556 {
 557 #ifndef HAVE_MINGW
 558         int i;
 559         struct sigaction act;
 560
 561         sigemptyset(&emptysigset);
 562         act.sa_handler = NULL;
 563         act.sa_mask = emptysigset;
 564         act.sa_flags = 0;
 565
 566         /* Set a default signal handler for every signal, errors will be
 567            ignored. */
 568         for(i = 0; i < NSIG; i++) {
 569                 if(!do_detach)
 570                         act.sa_handler = SIG_DFL;
 571                 else
 572                         act.sa_handler = unexpected_signal_handler;
 573                 sigaction(i, &act, NULL);
 574         }
 575
 576         /* If we didn't detach, allow coredumps */
 577         if(!do_detach)
 578                 sighandlers[3].handler = SIG_DFL;
 579
 580         /* Then, for each known signal that we want to catch, assign a
 581            handler to the signal, with error checking this time. */
 582         for(i = 0; sighandlers[i].signal; i++) {
 583                 act.sa_handler = sighandlers[i].handler;
 584                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 585                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 586                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 587                                         strerror(errno));
 588         }
 589 #endif
 590 }