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 sigalrm = false;
  40
  41 extern char *identname;
  42 extern char *pidfilename;
  43 extern char **g_argv;
  44 extern bool use_logfile;
  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_STOP:
 156                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 157                         break;
 158                 case SERVICE_CONTROL_SHUTDOWN:
 159                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 160                         break;
 161                 default:
 162                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 163                         return ERROR_CALL_NOT_IMPLEMENTED;
 164         }
 165
 166         event_loopexit(NULL);
 167         status.dwWaitHint = 30000;
 168         status.dwCurrentState = SERVICE_STOP_PENDING;
 169         SetServiceStatus(statushandle, &status);
 170         return NO_ERROR;
 171 }
 172
 173 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
 174 {
 175         int err = 1;
 176         extern int main2(int argc, char **argv);
 177
 178
 179         status.dwServiceType = SERVICE_WIN32;
 180         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 181         status.dwWin32ExitCode = 0;
 182         status.dwServiceSpecificExitCode = 0;
 183         status.dwCheckPoint = 0;
 184
 185         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 186
 187         if (!statushandle) {
 188                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 189                 err = 1;
 190         } else {
 191                 status.dwWaitHint = 30000;
 192                 status.dwCurrentState = SERVICE_START_PENDING;
 193                 SetServiceStatus(statushandle, &status);
 194
 195                 status.dwWaitHint = 0;
 196                 status.dwCurrentState = SERVICE_RUNNING;
 197                 SetServiceStatus(statushandle, &status);
 198
 199                 err = main2(argc, argv);
 200
 201                 status.dwWaitHint = 0;
 202                 status.dwCurrentState = SERVICE_STOPPED;
 203                 //status.dwWin32ExitCode = err;
 204                 SetServiceStatus(statushandle, &status);
 205         }
 206
 207         return;
 208 }
 209
 210 bool init_service(void) {
 211         SERVICE_TABLE_ENTRY services[] = {
 212                 {identname, run_service},
 213                 {NULL, NULL}
 214         };
 215
 216         if(!StartServiceCtrlDispatcher(services)) {
 217                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 218                         return false;
 219                 }
 220                 else
 221                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 222         }
 223
 224         return true;
 225 }
 226 #endif
 227
 228 #ifndef HAVE_MINGW
 229 /*
 230   check for an existing tinc for this net, and write pid to pidfile
 231 */
 232 static bool write_pidfile(void)
 233 {
 234         pid_t pid;
 235
 236         cp();
 237
 238         pid = check_pid(pidfilename);
 239
 240         if(pid) {
 241                 if(netname)
 242                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 243                                         netname, (long)pid);
 244                 else
 245                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 246                 return false;
 247         }
 248
 249         /* if it's locked, write-protected, or whatever */
 250         if(!write_pid(pidfilename)) {
 251                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 252                 return false;
 253         }
 254
 255         return true;
 256 }
 257 #endif
 258
 259 /*
 260   kill older tincd for this net
 261 */
 262 bool kill_other(int signal)
 263 {
 264 #ifndef HAVE_MINGW
 265         pid_t pid;
 266
 267         cp();
 268
 269         pid = read_pid(pidfilename);
 270
 271         if(!pid) {
 272                 if(netname)
 273                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 274                                         netname);
 275                 else
 276                         fprintf(stderr, _("No other tincd is running.\n"));
 277                 return false;
 278         }
 279
 280         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 281
 282         /* ESRCH is returned when no process with that pid is found */
 283         if(kill(pid, signal) && errno == ESRCH) {
 284                 if(netname)
 285                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 286                                         netname);
 287                 else
 288                         fprintf(stderr, _("The tincd is no longer running. "));
 289
 290                 fprintf(stderr, _("Removing stale lock file.\n"));
 291                 remove_pid(pidfilename);
 292         }
 293
 294         return true;
 295 #else
 296         return remove_service();
 297 #endif
 298 }
 299
 300 /*
 301   Detach from current terminal, write pidfile, kill parent
 302 */
 303 bool detach(void)
 304 {
 305         cp();
 306
 307         setup_signals();
 308
 309         /* First check if we can open a fresh new pidfile */
 310
 311 #ifndef HAVE_MINGW
 312         if(!write_pidfile())
 313                 return false;
 314
 315         /* If we succeeded in doing that, detach */
 316
 317         closelogger();
 318 #endif
 319
 320         if(do_detach) {
 321 #ifndef HAVE_MINGW
 322                 if(daemon(0, 0)) {
 323                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 324                                         strerror(errno));
 325                         return false;
 326                 }
 327
 328                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 329
 330                 if(!write_pid(pidfilename)) {
 331                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 332                         return false;
 333                 }
 334 #else
 335                 if(!statushandle)
 336                         exit(install_service());
 337 #endif
 338         }
 339
 340         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 341
 342         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 343                            VERSION, __DATE__, __TIME__, debug_level);
 344
 345         xalloc_fail_func = memory_full;
 346
 347         return true;
 348 }
 349
 350 bool execute_script(const char *name, char **envp)
 351 {
 352 #ifdef HAVE_SYSTEM
 353         int status, len;
 354         struct stat s;
 355         char *scriptname, *p;
 356         int i;
 357
 358         cp();
 359
 360 #ifndef HAVE_MINGW
 361         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 362 #else
 363         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 364 #endif
 365         if(len < 0)
 366                 return false;
 367
 368         scriptname[len - 1] = '\0';
 369
 370         /* First check if there is a script */
 371
 372         if(stat(scriptname + 1, &s)) {
 373                 free(scriptname);
 374                 return true;
 375         }
 376
 377         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 378
 379 #ifdef HAVE_PUTENV
 380         /* Set environment */
 381
 382         for(i = 0; envp[i]; i++)
 383                 putenv(envp[i]);
 384 #endif
 385
 386         scriptname[len - 1] = '\"';
 387         status = system(scriptname);
 388
 389         free(scriptname);
 390
 391         /* Unset environment */
 392
 393         for(i = 0; envp[i]; i++) {
 394                 char *e = strchr(envp[i], '=');
 395                 if(e) {
 396                         p = alloca(e - envp[i] + 1);
 397                         strncpy(p, envp[i], e - envp[i]);
 398                         p[e - envp[i]] = '\0';
 399                         putenv(p);
 400                 }
 401         }
 402
 403 #ifdef WEXITSTATUS
 404         if(status != -1) {
 405                 if(WIFEXITED(status)) { /* Child exited by itself */
 406                         if(WEXITSTATUS(status)) {
 407                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 408                                            name, WEXITSTATUS(status));
 409                                 return false;
 410                         }
 411                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 412                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 413                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 414                         return false;
 415                 } else {                        /* Something strange happened */
 416                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 417                         return false;
 418                 }
 419         } else {
 420                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 421                 return false;
 422         }
 423 #endif
 424 #endif
 425         return true;
 426 }
 427
 428
 429 /*
 430   Signal handlers.
 431 */
 432
 433 #ifndef HAVE_MINGW
 434 static RETSIGTYPE fatal_signal_square(int a)
 435 {
 436         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 437                    strsignal(a));
 438         cp_trace();
 439         exit(1);
 440 }
 441
 442 static RETSIGTYPE fatal_signal_handler(int a)
 443 {
 444         struct sigaction act;
 445         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 446         cp_trace();
 447
 448         if(do_detach) {
 449                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 450
 451                 act.sa_handler = fatal_signal_square;
 452                 act.sa_mask = emptysigset;
 453                 act.sa_flags = 0;
 454                 sigaction(SIGSEGV, &act, NULL);
 455
 456                 close_network_connections();
 457                 sleep(5);
 458                 remove_pid(pidfilename);
 459                 execvp(g_argv[0], g_argv);
 460         } else {
 461                 logger(LOG_NOTICE, _("Not restarting."));
 462                 exit(1);
 463         }
 464 }
 465
 466 static RETSIGTYPE unexpected_signal_handler(int a)
 467 {
 468         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 469         cp_trace();
 470 }
 471
 472 static RETSIGTYPE ignore_signal_handler(int a)
 473 {
 474         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 475 }
 476
 477 static struct {
 478         int signal;
 479         void (*handler)(int);
 480 } sighandlers[] = {
 481         {SIGSEGV, fatal_signal_handler},
 482         {SIGBUS, fatal_signal_handler},
 483         {SIGILL, fatal_signal_handler},
 484         {SIGPIPE, ignore_signal_handler},
 485         {SIGCHLD, ignore_signal_handler},
 486         {0, NULL}
 487 };
 488 #endif
 489
 490 void setup_signals(void)
 491 {
 492 #ifndef HAVE_MINGW
 493         int i;
 494         struct sigaction act;
 495
 496         sigemptyset(&emptysigset);
 497         act.sa_handler = NULL;
 498         act.sa_mask = emptysigset;
 499         act.sa_flags = 0;
 500
 501         /* Set a default signal handler for every signal, errors will be
 502            ignored. */
 503         for(i = 0; i < NSIG; i++) {
 504                 if(!do_detach)
 505                         act.sa_handler = SIG_DFL;
 506                 else
 507                         act.sa_handler = unexpected_signal_handler;
 508                 sigaction(i, &act, NULL);
 509         }
 510
 511         /* If we didn't detach, allow coredumps */
 512         if(!do_detach)
 513                 sighandlers[0].handler = SIG_DFL;
 514
 515         /* Then, for each known signal that we want to catch, assign a
 516            handler to the signal, with error checking this time. */
 517         for(i = 0; sighandlers[i].signal; i++) {
 518                 act.sa_handler = sighandlers[i].handler;
 519                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 520                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 521                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 522                                         strerror(errno));
 523         }
 524 #endif
 525 }