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

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2005 Ivo Timmermans,
   4                   2000-2009 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 along
  17     with this program; if not, write to the Free Software Foundation, Inc.,
  18     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21 #include "system.h"
  22
  23 #include "conf.h"
  24 #include "connection.h"
  25 #include "device.h"
  26 #include "edge.h"
  27 #include "logger.h"
  28 #include "node.h"
  29 #include "pidfile.h"
  30 #include "process.h"
  31 #include "subnet.h"
  32 #include "utils.h"
  33 #include "xalloc.h"
  34
  35 /* If zero, don't detach from the terminal. */
  36 bool do_detach = true;
  37 bool sighup = false;
  38 bool sigalrm = false;
  39
  40 extern char *identname;
  41 extern char *pidfilename;
  42 extern char **g_argv;
  43 extern bool use_logfile;
  44 extern volatile bool running;
  45
  46 sigset_t emptysigset;
  47
  48 static int saved_debug_level = -1;
  49
  50 static void memory_full(int size) {
  51         logger(LOG_ERR, "Memory exhausted (couldn't allocate %d bytes), exitting.", size);
  52         exit(1);
  53 }
  54
  55 /* Some functions the less gifted operating systems might lack... */
  56
  57 #ifdef HAVE_MINGW
  58 extern char *identname;
  59 extern char *program_name;
  60 extern char **g_argv;
  61
  62 static SC_HANDLE manager = NULL;
  63 static SC_HANDLE service = NULL;
  64 static SERVICE_STATUS status = {0};
  65 static SERVICE_STATUS_HANDLE statushandle = 0;
  66
  67 bool install_service(void) {
  68         char command[4096] = "\"";
  69         char **argp;
  70         bool space;
  71         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  72
  73         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  74         if(!manager) {
  75                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
  76                 return false;
  77         }
  78
  79         if(!strchr(program_name, '\\')) {
  80                 GetCurrentDirectory(sizeof command - 1, command + 1);
  81                 strncat(command, "\\", sizeof command - strlen(command));
  82         }
  83
  84         strncat(command, program_name, sizeof command - strlen(command));
  85
  86         strncat(command, "\"", sizeof command - strlen(command));
  87
  88         for(argp = g_argv + 1; *argp; argp++) {
  89                 space = strchr(*argp, ' ');
  90                 strncat(command, " ", sizeof command - strlen(command));
  91
  92                 if(space)
  93                         strncat(command, "\"", sizeof command - strlen(command));
  94
  95                 strncat(command, *argp, sizeof command - strlen(command));
  96
  97                 if(space)
  98                         strncat(command, "\"", sizeof command - strlen(command));
  99         }
 100
 101         service = CreateService(manager, identname, identname,
 102                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 103                         command, NULL, NULL, NULL, NULL, NULL);
 104
 105         if(!service) {
 106                 logger(LOG_ERR, "Could not create %s service: %s", identname, winerror(GetLastError()));
 107                 return false;
 108         }
 109
 110         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 111
 112         logger(LOG_INFO, "%s service installed", identname);
 113
 114         if(!StartService(service, 0, NULL))
 115                 logger(LOG_WARNING, "Could not start %s service: %s", identname, winerror(GetLastError()));
 116         else
 117                 logger(LOG_INFO, "%s service started", identname);
 118
 119         return true;
 120 }
 121
 122 bool remove_service(void) {
 123         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 124         if(!manager) {
 125                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
 126                 return false;
 127         }
 128
 129         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 130
 131         if(!service) {
 132                 logger(LOG_ERR, "Could not open %s service: %s", identname, winerror(GetLastError()));
 133                 return false;
 134         }
 135
 136         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 137                 logger(LOG_ERR, "Could not stop %s service: %s", identname, winerror(GetLastError()));
 138         else
 139                 logger(LOG_INFO, "%s service stopped", identname);
 140
 141         if(!DeleteService(service)) {
 142                 logger(LOG_ERR, "Could not remove %s service: %s", identname, winerror(GetLastError()));
 143                 return false;
 144         }
 145
 146         logger(LOG_INFO, "%s service removed", identname);
 147
 148         return true;
 149 }
 150
 151 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 152         switch(request) {
 153                 case SERVICE_CONTROL_INTERROGATE:
 154                         SetServiceStatus(statushandle, &status);
 155                         return NO_ERROR;
 156                 case SERVICE_CONTROL_STOP:
 157                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_STOP");
 158                         break;
 159                 case SERVICE_CONTROL_SHUTDOWN:
 160                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_SHUTDOWN");
 161                         break;
 162                 default:
 163                         logger(LOG_WARNING, "Got unexpected request %d", request);
 164                         return ERROR_CALL_NOT_IMPLEMENTED;
 165         }
 166
 167         if(running) {
 168                 running = false;
 169                 status.dwWaitHint = 30000;
 170                 status.dwCurrentState = SERVICE_STOP_PENDING;
 171                 SetServiceStatus(statushandle, &status);
 172                 return NO_ERROR;
 173         } else {
 174                 status.dwWaitHint = 0;
 175                 status.dwCurrentState = SERVICE_STOPPED;
 176                 SetServiceStatus(statushandle, &status);
 177                 exit(1);
 178         }
 179
 180 }
 181
 182 VOID WINAPI run_service(DWORD argc, LPTSTR* argv) {
 183         int err = 1;
 184         extern int main2(int argc, char **argv);
 185
 186
 187         status.dwServiceType = SERVICE_WIN32;
 188         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 189         status.dwWin32ExitCode = 0;
 190         status.dwServiceSpecificExitCode = 0;
 191         status.dwCheckPoint = 0;
 192
 193         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 194
 195         if (!statushandle) {
 196                 logger(LOG_ERR, "System call `%s' failed: %s", "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 197                 err = 1;
 198         } else {
 199                 status.dwWaitHint = 30000;
 200                 status.dwCurrentState = SERVICE_START_PENDING;
 201                 SetServiceStatus(statushandle, &status);
 202
 203                 status.dwWaitHint = 0;
 204                 status.dwCurrentState = SERVICE_RUNNING;
 205                 SetServiceStatus(statushandle, &status);
 206
 207                 err = main2(argc, argv);
 208
 209                 status.dwWaitHint = 0;
 210                 status.dwCurrentState = SERVICE_STOPPED;
 211                 //status.dwWin32ExitCode = err;
 212                 SetServiceStatus(statushandle, &status);
 213         }
 214
 215         return;
 216 }
 217
 218 bool init_service(void) {
 219         SERVICE_TABLE_ENTRY services[] = {
 220                 {identname, run_service},
 221                 {NULL, NULL}
 222         };
 223
 224         if(!StartServiceCtrlDispatcher(services)) {
 225                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 226                         return false;
 227                 }
 228                 else
 229                         logger(LOG_ERR, "System call `%s' failed: %s", "StartServiceCtrlDispatcher", winerror(GetLastError()));
 230         }
 231
 232         return true;
 233 }
 234 #endif
 235
 236 #ifndef HAVE_MINGW
 237 /*
 238   check for an existing tinc for this net, and write pid to pidfile
 239 */
 240 static bool write_pidfile(void) {
 241         pid_t pid;
 242
 243         pid = check_pid(pidfilename);
 244
 245         if(pid) {
 246                 if(netname)
 247                         fprintf(stderr, "A tincd is already running for net `%s' with pid %ld.\n",
 248                                         netname, (long)pid);
 249                 else
 250                         fprintf(stderr, "A tincd is already running with pid %ld.\n", (long)pid);
 251                 return false;
 252         }
 253
 254         /* if it's locked, write-protected, or whatever */
 255         if(!write_pid(pidfilename)) {
 256                 fprintf(stderr, "Could write pid file %s: %s\n", pidfilename, strerror(errno));
 257                 return false;
 258         }
 259
 260         return true;
 261 }
 262 #endif
 263
 264 /*
 265   kill older tincd for this net
 266 */
 267 bool kill_other(int signal) {
 268 #ifndef HAVE_MINGW
 269         pid_t pid;
 270
 271         pid = read_pid(pidfilename);
 272
 273         if(!pid) {
 274                 if(netname)
 275                         fprintf(stderr, "No other tincd is running for net `%s'.\n",
 276                                         netname);
 277                 else
 278                         fprintf(stderr, "No other tincd is running.\n");
 279                 return false;
 280         }
 281
 282         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 283
 284         /* ESRCH is returned when no process with that pid is found */
 285         if(kill(pid, signal) && errno == ESRCH) {
 286                 if(netname)
 287                         fprintf(stderr, "The tincd for net `%s' is no longer running. ",
 288                                         netname);
 289                 else
 290                         fprintf(stderr, "The tincd is no longer running. ");
 291
 292                 fprintf(stderr, "Removing stale lock file.\n");
 293                 remove_pid(pidfilename);
 294         }
 295
 296         return true;
 297 #else
 298         return remove_service();
 299 #endif
 300 }
 301
 302 /*
 303   Detach from current terminal, write pidfile, kill parent
 304 */
 305 bool detach(void) {
 306         setup_signals();
 307
 308         /* First check if we can open a fresh new pidfile */
 309
 310 #ifndef HAVE_MINGW
 311         if(!write_pidfile())
 312                 return false;
 313
 314         /* If we succeeded in doing that, detach */
 315
 316         closelogger();
 317 #endif
 318
 319         if(do_detach) {
 320 #ifndef HAVE_MINGW
 321                 if(daemon(0, 0)) {
 322                         fprintf(stderr, "Couldn't detach from terminal: %s",
 323                                         strerror(errno));
 324                         return false;
 325                 }
 326
 327                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 328
 329                 if(!write_pid(pidfilename)) {
 330                         fprintf(stderr, "Could not write pid file %s: %s\n", pidfilename, strerror(errno));
 331                         return false;
 332                 }
 333 #else
 334                 if(!statushandle)
 335                         exit(install_service());
 336 #endif
 337         }
 338
 339         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 340
 341         logger(LOG_NOTICE, "tincd %s (%s %s) starting, debug level %d",
 342                            VERSION, __DATE__, __TIME__, debug_level);
 343
 344         xalloc_fail_func = memory_full;
 345
 346         return true;
 347 }
 348
 349 bool execute_script(const char *name, char **envp) {
 350 #ifdef HAVE_SYSTEM
 351         int status, len;
 352         char *scriptname, *p;
 353         int i;
 354
 355 #ifndef HAVE_MINGW
 356         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 357 #else
 358         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 359 #endif
 360         if(len < 0)
 361                 return false;
 362
 363         scriptname[len - 1] = '\0';
 364
 365 #ifndef HAVE_TUNEMU
 366         /* First check if there is a script */
 367
 368         if(access(scriptname + 1, F_OK)) {
 369                 free(scriptname);
 370                 return true;
 371         }
 372 #endif
 373
 374         ifdebug(STATUS) logger(LOG_INFO, "Executing script %s", name);
 375
 376 #ifdef HAVE_PUTENV
 377         /* Set environment */
 378
 379         for(i = 0; envp[i]; i++)
 380                 putenv(envp[i]);
 381 #endif
 382
 383         scriptname[len - 1] = '\"';
 384         status = system(scriptname);
 385
 386         free(scriptname);
 387
 388         /* Unset environment */
 389
 390         for(i = 0; envp[i]; i++) {
 391                 char *e = strchr(envp[i], '=');
 392                 if(e) {
 393                         p = alloca(e - envp[i] + 1);
 394                         strncpy(p, envp[i], e - envp[i]);
 395                         p[e - envp[i]] = '\0';
 396                         putenv(p);
 397                 }
 398         }
 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         logger(LOG_NOTICE, "Got %s signal", "TERM");
 433         if(running)
 434                 running = false;
 435         else
 436                 exit(1);
 437 }
 438
 439 static RETSIGTYPE sigquit_handler(int a) {
 440         logger(LOG_NOTICE, "Got %s signal", "QUIT");
 441         if(running)
 442                 running = false;
 443         else
 444                 exit(1);
 445 }
 446
 447 static RETSIGTYPE fatal_signal_square(int a) {
 448         logger(LOG_ERR, "Got another fatal signal %d (%s): not restarting.", a,
 449                    strsignal(a));
 450         exit(1);
 451 }
 452
 453 static RETSIGTYPE fatal_signal_handler(int a) {
 454         struct sigaction act;
 455         logger(LOG_ERR, "Got fatal signal %d (%s)", a, strsignal(a));
 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         logger(LOG_NOTICE, "Got %s signal", "HUP");
 477         sighup = true;
 478 }
 479
 480 static RETSIGTYPE sigint_handler(int a) {
 481         logger(LOG_NOTICE, "Got %s signal", "INT");
 482
 483         if(saved_debug_level != -1) {
 484                 logger(LOG_NOTICE, "Reverting to old debug level (%d)",
 485                         saved_debug_level);
 486                 debug_level = saved_debug_level;
 487                 saved_debug_level = -1;
 488         } else {
 489                 logger(LOG_NOTICE,
 490                         "Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d.",
 491                         debug_level);
 492                 saved_debug_level = debug_level;
 493                 debug_level = 5;
 494         }
 495 }
 496
 497 static RETSIGTYPE sigalrm_handler(int a) {
 498         logger(LOG_NOTICE, "Got %s signal", "ALRM");
 499         sigalrm = true;
 500 }
 501
 502 static RETSIGTYPE sigusr1_handler(int a) {
 503         dump_connections();
 504 }
 505
 506 static RETSIGTYPE sigusr2_handler(int a) {
 507         dump_device_stats();
 508         dump_nodes();
 509         dump_edges();
 510         dump_subnets();
 511 }
 512
 513 static RETSIGTYPE sigwinch_handler(int a) {
 514         do_purge = true;
 515 }
 516
 517 static RETSIGTYPE unexpected_signal_handler(int a) {
 518         logger(LOG_WARNING, "Got unexpected signal %d (%s)", a, strsignal(a));
 519 }
 520
 521 static RETSIGTYPE ignore_signal_handler(int a) {
 522         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignored signal %d (%s)", a, strsignal(a));
 523 }
 524
 525 static struct {
 526         int signal;
 527         void (*handler)(int);
 528 } sighandlers[] = {
 529         {SIGHUP, sighup_handler},
 530         {SIGTERM, sigterm_handler},
 531         {SIGQUIT, sigquit_handler},
 532         {SIGSEGV, fatal_signal_handler},
 533         {SIGBUS, fatal_signal_handler},
 534         {SIGILL, fatal_signal_handler},
 535         {SIGPIPE, ignore_signal_handler},
 536         {SIGINT, sigint_handler},
 537         {SIGUSR1, sigusr1_handler},
 538         {SIGUSR2, sigusr2_handler},
 539         {SIGCHLD, ignore_signal_handler},
 540         {SIGALRM, sigalrm_handler},
 541         {SIGWINCH, sigwinch_handler},
 542         {0, NULL}
 543 };
 544 #endif
 545
 546 void setup_signals(void) {
 547 #ifndef HAVE_MINGW
 548         int i;
 549         struct sigaction act;
 550
 551         sigemptyset(&emptysigset);
 552         act.sa_handler = NULL;
 553         act.sa_mask = emptysigset;
 554         act.sa_flags = 0;
 555
 556         /* Set a default signal handler for every signal, errors will be
 557            ignored. */
 558         for(i = 1; i < NSIG; i++) {
 559                 if(!do_detach)
 560                         act.sa_handler = SIG_DFL;
 561                 else
 562                         act.sa_handler = unexpected_signal_handler;
 563                 sigaction(i, &act, NULL);
 564         }
 565
 566         /* If we didn't detach, allow coredumps */
 567         if(!do_detach)
 568                 sighandlers[3].handler = SIG_DFL;
 569
 570         /* Then, for each known signal that we want to catch, assign a
 571            handler to the signal, with error checking this time. */
 572         for(i = 0; sighandlers[i].signal; i++) {
 573                 act.sa_handler = sighandlers[i].handler;
 574                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 575                         fprintf(stderr, "Installing signal handler for signal %d (%s) failed: %s\n",
 576                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 577                                         strerror(errno));
 578         }
 579 #endif
 580 }