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