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         cp_trace();
  53         exit(1);
  54 }
  55
  56 /* Some functions the less gifted operating systems might lack... */
  57
  58 #ifdef HAVE_MINGW
  59 extern char *identname;
  60 extern char *program_name;
  61 extern char **g_argv;
  62
  63 static SC_HANDLE manager = NULL;
  64 static SC_HANDLE service = NULL;
  65 static SERVICE_STATUS status = {0};
  66 static SERVICE_STATUS_HANDLE statushandle = 0;
  67
  68 bool install_service(void) {
  69         char command[4096] = "\"";
  70         char **argp;
  71         bool space;
  72         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  73
  74         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  75         if(!manager) {
  76                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  77                 return false;
  78         }
  79
  80         if(!strchr(program_name, '\\')) {
  81                 GetCurrentDirectory(sizeof command - 1, command + 1);
  82                 strncat(command, "\\", sizeof command - strlen(command));
  83         }
  84
  85         strncat(command, program_name, sizeof command - strlen(command));
  86
  87         strncat(command, "\"", sizeof command - strlen(command));
  88
  89         for(argp = g_argv + 1; *argp; argp++) {
  90                 space = strchr(*argp, ' ');
  91                 strncat(command, " ", sizeof command - strlen(command));
  92
  93                 if(space)
  94                         strncat(command, "\"", sizeof command - strlen(command));
  95
  96                 strncat(command, *argp, sizeof command - strlen(command));
  97
  98                 if(space)
  99                         strncat(command, "\"", sizeof command - strlen(command));
 100         }
 101
 102         service = CreateService(manager, identname, identname,
 103                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 104                         command, NULL, NULL, NULL, NULL, NULL);
 105
 106         if(!service) {
 107                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 108                 return false;
 109         }
 110
 111         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 112
 113         logger(LOG_INFO, _("%s service installed"), identname);
 114
 115         if(!StartService(service, 0, NULL))
 116                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 117         else
 118                 logger(LOG_INFO, _("%s service started"), identname);
 119
 120         return true;
 121 }
 122
 123 bool remove_service(void) {
 124         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 125         if(!manager) {
 126                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 127                 return false;
 128         }
 129
 130         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 131
 132         if(!service) {
 133                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 134                 return false;
 135         }
 136
 137         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 138                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 139         else
 140                 logger(LOG_INFO, _("%s service stopped"), identname);
 141
 142         if(!DeleteService(service)) {
 143                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 144                 return false;
 145         }
 146
 147         logger(LOG_INFO, _("%s service removed"), identname);
 148
 149         return true;
 150 }
 151
 152 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 153         switch(request) {
 154                 case SERVICE_CONTROL_INTERROGATE:
 155                         SetServiceStatus(statushandle, &status);
 156                         return NO_ERROR;
 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         int err = 1;
 185         extern int main2(int argc, char **argv);
 186
 187
 188         status.dwServiceType = SERVICE_WIN32;
 189         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 190         status.dwWin32ExitCode = 0;
 191         status.dwServiceSpecificExitCode = 0;
 192         status.dwCheckPoint = 0;
 193
 194         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 195
 196         if (!statushandle) {
 197                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 198                 err = 1;
 199         } else {
 200                 status.dwWaitHint = 30000;
 201                 status.dwCurrentState = SERVICE_START_PENDING;
 202                 SetServiceStatus(statushandle, &status);
 203
 204                 status.dwWaitHint = 0;
 205                 status.dwCurrentState = SERVICE_RUNNING;
 206                 SetServiceStatus(statushandle, &status);
 207
 208                 err = main2(argc, argv);
 209
 210                 status.dwWaitHint = 0;
 211                 status.dwCurrentState = SERVICE_STOPPED;
 212                 //status.dwWin32ExitCode = err;
 213                 SetServiceStatus(statushandle, &status);
 214         }
 215
 216         return;
 217 }
 218
 219 bool init_service(void) {
 220         SERVICE_TABLE_ENTRY services[] = {
 221                 {identname, run_service},
 222                 {NULL, NULL}
 223         };
 224
 225         if(!StartServiceCtrlDispatcher(services)) {
 226                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 227                         return false;
 228                 }
 229                 else
 230                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 231         }
 232
 233         return true;
 234 }
 235 #endif
 236
 237 #ifndef HAVE_MINGW
 238 /*
 239   check for an existing tinc for this net, and write pid to pidfile
 240 */
 241 static bool write_pidfile(void) {
 242         pid_t pid;
 243
 244         cp();
 245
 246         pid = check_pid(pidfilename);
 247
 248         if(pid) {
 249                 if(netname)
 250                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 251                                         netname, (long)pid);
 252                 else
 253                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 254                 return false;
 255         }
 256
 257         /* if it's locked, write-protected, or whatever */
 258         if(!write_pid(pidfilename)) {
 259                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 260                 return false;
 261         }
 262
 263         return true;
 264 }
 265 #endif
 266
 267 /*
 268   kill older tincd for this net
 269 */
 270 bool kill_other(int signal) {
 271 #ifndef HAVE_MINGW
 272         pid_t pid;
 273
 274         cp();
 275
 276         pid = read_pid(pidfilename);
 277
 278         if(!pid) {
 279                 if(netname)
 280                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 281                                         netname);
 282                 else
 283                         fprintf(stderr, _("No other tincd is running.\n"));
 284                 return false;
 285         }
 286
 287         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 288
 289         /* ESRCH is returned when no process with that pid is found */
 290         if(kill(pid, signal) && errno == ESRCH) {
 291                 if(netname)
 292                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 293                                         netname);
 294                 else
 295                         fprintf(stderr, _("The tincd is no longer running. "));
 296
 297                 fprintf(stderr, _("Removing stale lock file.\n"));
 298                 remove_pid(pidfilename);
 299         }
 300
 301         return true;
 302 #else
 303         return remove_service();
 304 #endif
 305 }
 306
 307 /*
 308   Detach from current terminal, write pidfile, kill parent
 309 */
 310 bool detach(void) {
 311         cp();
 312
 313         setup_signals();
 314
 315         /* First check if we can open a fresh new pidfile */
 316
 317 #ifndef HAVE_MINGW
 318         if(!write_pidfile())
 319                 return false;
 320
 321         /* If we succeeded in doing that, detach */
 322
 323         closelogger();
 324 #endif
 325
 326         if(do_detach) {
 327 #ifndef HAVE_MINGW
 328                 if(daemon(0, 0)) {
 329                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 330                                         strerror(errno));
 331                         return false;
 332                 }
 333
 334                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 335
 336                 if(!write_pid(pidfilename)) {
 337                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 338                         return false;
 339                 }
 340 #else
 341                 if(!statushandle)
 342                         exit(install_service());
 343 #endif
 344         }
 345
 346         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 347
 348         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 349                            VERSION, __DATE__, __TIME__, debug_level);
 350
 351         xalloc_fail_func = memory_full;
 352
 353         return true;
 354 }
 355
 356 bool execute_script(const char *name, char **envp) {
 357 #ifdef HAVE_SYSTEM
 358         int status, len;
 359         char *scriptname, *p;
 360         int i;
 361
 362         cp();
 363
 364 #ifndef HAVE_MINGW
 365         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 366 #else
 367         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 368 #endif
 369         if(len < 0)
 370                 return false;
 371
 372         scriptname[len - 1] = '\0';
 373
 374 #ifndef HAVE_TUNEMU
 375         /* First check if there is a script */
 376
 377         if(access(scriptname + 1, F_OK)) {
 378                 free(scriptname);
 379                 return true;
 380         }
 381 #endif
 382
 383         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 384
 385 #ifdef HAVE_PUTENV
 386         /* Set environment */
 387
 388         for(i = 0; envp[i]; i++)
 389                 putenv(envp[i]);
 390 #endif
 391
 392         scriptname[len - 1] = '\"';
 393         status = system(scriptname);
 394
 395         free(scriptname);
 396
 397         /* Unset environment */
 398
 399         for(i = 0; envp[i]; i++) {
 400                 char *e = strchr(envp[i], '=');
 401                 if(e) {
 402                         p = alloca(e - envp[i] + 1);
 403                         strncpy(p, envp[i], e - envp[i]);
 404                         p[e - envp[i]] = '\0';
 405                         putenv(p);
 406                 }
 407         }
 408
 409 #ifdef WEXITSTATUS
 410         if(status != -1) {
 411                 if(WIFEXITED(status)) { /* Child exited by itself */
 412                         if(WEXITSTATUS(status)) {
 413                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 414                                            name, WEXITSTATUS(status));
 415                                 return false;
 416                         }
 417                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 418                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 419                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 420                         return false;
 421                 } else {                        /* Something strange happened */
 422                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 423                         return false;
 424                 }
 425         } else {
 426                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 427                 return false;
 428         }
 429 #endif
 430 #endif
 431         return true;
 432 }
 433
 434
 435 /*
 436   Signal handlers.
 437 */
 438
 439 #ifndef HAVE_MINGW
 440 static RETSIGTYPE sigterm_handler(int a) {
 441         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
 442         if(running)
 443                 running = false;
 444         else
 445                 exit(1);
 446 }
 447
 448 static RETSIGTYPE sigquit_handler(int a) {
 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         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 458                    strsignal(a));
 459         cp_trace();
 460         exit(1);
 461 }
 462
 463 static RETSIGTYPE fatal_signal_handler(int a) {
 464         struct sigaction act;
 465         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 466         cp_trace();
 467
 468         if(do_detach) {
 469                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 470
 471                 act.sa_handler = fatal_signal_square;
 472                 act.sa_mask = emptysigset;
 473                 act.sa_flags = 0;
 474                 sigaction(SIGSEGV, &act, NULL);
 475
 476                 close_network_connections();
 477                 sleep(5);
 478                 remove_pid(pidfilename);
 479                 execvp(g_argv[0], g_argv);
 480         } else {
 481                 logger(LOG_NOTICE, _("Not restarting."));
 482                 exit(1);
 483         }
 484 }
 485
 486 static RETSIGTYPE sighup_handler(int a) {
 487         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
 488         sighup = true;
 489 }
 490
 491 static RETSIGTYPE sigint_handler(int a) {
 492         logger(LOG_NOTICE, _("Got %s signal"), "INT");
 493
 494         if(saved_debug_level != -1) {
 495                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
 496                         saved_debug_level);
 497                 debug_level = saved_debug_level;
 498                 saved_debug_level = -1;
 499         } else {
 500                 logger(LOG_NOTICE,
 501                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
 502                         debug_level);
 503                 saved_debug_level = debug_level;
 504                 debug_level = 5;
 505         }
 506 }
 507
 508 static RETSIGTYPE sigalrm_handler(int a) {
 509         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
 510         sigalrm = true;
 511 }
 512
 513 static RETSIGTYPE sigusr1_handler(int a) {
 514         dump_connections();
 515 }
 516
 517 static RETSIGTYPE sigusr2_handler(int a) {
 518         dump_device_stats();
 519         dump_nodes();
 520         dump_edges();
 521         dump_subnets();
 522 }
 523
 524 static RETSIGTYPE sigwinch_handler(int a) {
 525         do_purge = true;
 526 }
 527
 528 static RETSIGTYPE unexpected_signal_handler(int a) {
 529         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 530         cp_trace();
 531 }
 532
 533 static RETSIGTYPE ignore_signal_handler(int a) {
 534         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 535 }
 536
 537 static struct {
 538         int signal;
 539         void (*handler)(int);
 540 } sighandlers[] = {
 541         {SIGHUP, sighup_handler},
 542         {SIGTERM, sigterm_handler},
 543         {SIGQUIT, sigquit_handler},
 544         {SIGSEGV, fatal_signal_handler},
 545         {SIGBUS, fatal_signal_handler},
 546         {SIGILL, fatal_signal_handler},
 547         {SIGPIPE, ignore_signal_handler},
 548         {SIGINT, sigint_handler},
 549         {SIGUSR1, sigusr1_handler},
 550         {SIGUSR2, sigusr2_handler},
 551         {SIGCHLD, ignore_signal_handler},
 552         {SIGALRM, sigalrm_handler},
 553         {SIGWINCH, sigwinch_handler},
 554         {0, NULL}
 555 };
 556 #endif
 557
 558 void setup_signals(void) {
 559 #ifndef HAVE_MINGW
 560         int i;
 561         struct sigaction act;
 562
 563         sigemptyset(&emptysigset);
 564         act.sa_handler = NULL;
 565         act.sa_mask = emptysigset;
 566         act.sa_flags = 0;
 567
 568         /* Set a default signal handler for every signal, errors will be
 569            ignored. */
 570         for(i = 1; i < NSIG; i++) {
 571                 if(!do_detach)
 572                         act.sa_handler = SIG_DFL;
 573                 else
 574                         act.sa_handler = unexpected_signal_handler;
 575                 sigaction(i, &act, NULL);
 576         }
 577
 578         /* If we didn't detach, allow coredumps */
 579         if(!do_detach)
 580                 sighandlers[3].handler = SIG_DFL;
 581
 582         /* Then, for each known signal that we want to catch, assign a
 583            handler to the signal, with error checking this time. */
 584         for(i = 0; sighandlers[i].signal; i++) {
 585                 act.sa_handler = sighandlers[i].handler;
 586                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 587                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 588                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 589                                         strerror(errno));
 590         }
 591 #endif
 592 }