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 extern volatile bool running;
  46
  47 sigset_t emptysigset;
  48
  49 static int saved_debug_level = -1;
  50
  51 static void memory_full(int size)
  52 {
  53         logger(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size);
  54         cp_trace();
  55         exit(1);
  56 }
  57
  58 /* Some functions the less gifted operating systems might lack... */
  59
  60 #ifdef HAVE_MINGW
  61 extern char *identname;
  62 extern char *program_name;
  63 extern char **g_argv;
  64
  65 static SC_HANDLE manager = NULL;
  66 static SC_HANDLE service = NULL;
  67 static SERVICE_STATUS status = {0};
  68 static SERVICE_STATUS_HANDLE statushandle = 0;
  69
  70 bool install_service(void) {
  71         char command[4096] = "\"";
  72         char **argp;
  73         bool space;
  74         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  75
  76         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  77         if(!manager) {
  78                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  79                 return false;
  80         }
  81
  82         if(!strchr(program_name, '\\')) {
  83                 GetCurrentDirectory(sizeof command - 1, command + 1);
  84                 strncat(command, "\\", sizeof command - strlen(command));
  85         }
  86
  87         strncat(command, program_name, sizeof command - strlen(command));
  88
  89         strncat(command, "\"", sizeof command - strlen(command));
  90
  91         for(argp = g_argv + 1; *argp; argp++) {
  92                 space = strchr(*argp, ' ');
  93                 strncat(command, " ", sizeof command - strlen(command));
  94
  95                 if(space)
  96                         strncat(command, "\"", sizeof command - strlen(command));
  97
  98                 strncat(command, *argp, sizeof command - strlen(command));
  99
 100                 if(space)
 101                         strncat(command, "\"", sizeof command - strlen(command));
 102         }
 103
 104         service = CreateService(manager, identname, identname,
 105                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 106                         command, NULL, NULL, NULL, NULL, NULL);
 107
 108         if(!service) {
 109                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 110                 return false;
 111         }
 112
 113         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 114
 115         logger(LOG_INFO, _("%s service installed"), identname);
 116
 117         if(!StartService(service, 0, NULL))
 118                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 119         else
 120                 logger(LOG_INFO, _("%s service started"), identname);
 121
 122         return true;
 123 }
 124
 125 bool remove_service(void) {
 126         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 127         if(!manager) {
 128                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 129                 return false;
 130         }
 131
 132         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 133
 134         if(!service) {
 135                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 136                 return false;
 137         }
 138
 139         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 140                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 141         else
 142                 logger(LOG_INFO, _("%s service stopped"), identname);
 143
 144         if(!DeleteService(service)) {
 145                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 146                 return false;
 147         }
 148
 149         logger(LOG_INFO, _("%s service removed"), identname);
 150
 151         return true;
 152 }
 153
 154 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 155         switch(request) {
 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 {
 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 {
 243         pid_t pid;
 244
 245         cp();
 246
 247         pid = check_pid(pidfilename);
 248
 249         if(pid) {
 250                 if(netname)
 251                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 252                                         netname, (long)pid);
 253                 else
 254                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 255                 return false;
 256         }
 257
 258         /* if it's locked, write-protected, or whatever */
 259         if(!write_pid(pidfilename)) {
 260                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 261                 return false;
 262         }
 263
 264         return true;
 265 }
 266 #endif
 267
 268 /*
 269   kill older tincd for this net
 270 */
 271 bool kill_other(int signal)
 272 {
 273 #ifndef HAVE_MINGW
 274         pid_t pid;
 275
 276         cp();
 277
 278         pid = read_pid(pidfilename);
 279
 280         if(!pid) {
 281                 if(netname)
 282                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 283                                         netname);
 284                 else
 285                         fprintf(stderr, _("No other tincd is running.\n"));
 286                 return false;
 287         }
 288
 289         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 290
 291         /* ESRCH is returned when no process with that pid is found */
 292         if(kill(pid, signal) && errno == ESRCH) {
 293                 if(netname)
 294                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 295                                         netname);
 296                 else
 297                         fprintf(stderr, _("The tincd is no longer running. "));
 298
 299                 fprintf(stderr, _("Removing stale lock file.\n"));
 300                 remove_pid(pidfilename);
 301         }
 302
 303         return true;
 304 #else
 305         return remove_service();
 306 #endif
 307 }
 308
 309 /*
 310   Detach from current terminal, write pidfile, kill parent
 311 */
 312 bool detach(void)
 313 {
 314         cp();
 315
 316         setup_signals();
 317
 318         /* First check if we can open a fresh new pidfile */
 319
 320 #ifndef HAVE_MINGW
 321         if(!write_pidfile())
 322                 return false;
 323
 324         /* If we succeeded in doing that, detach */
 325
 326         closelogger();
 327 #endif
 328
 329         if(do_detach) {
 330 #ifndef HAVE_MINGW
 331                 if(daemon(0, 0)) {
 332                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 333                                         strerror(errno));
 334                         return false;
 335                 }
 336
 337                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 338
 339                 if(!write_pid(pidfilename)) {
 340                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 341                         return false;
 342                 }
 343 #else
 344                 if(!statushandle)
 345                         exit(install_service());
 346 #endif
 347         }
 348
 349         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 350
 351         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 352                            VERSION, __DATE__, __TIME__, debug_level);
 353
 354         xalloc_fail_func = memory_full;
 355
 356         return true;
 357 }
 358
 359 bool execute_script(const char *name, char **envp)
 360 {
 361 #ifdef HAVE_SYSTEM
 362         int status, len;
 363         struct stat s;
 364         char *scriptname, *p;
 365         int i;
 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                 free(scriptname);
 383                 return true;
 384         }
 385
 386         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 387
 388 #ifdef HAVE_PUTENV
 389         /* Set environment */
 390
 391         for(i = 0; envp[i]; i++)
 392                 putenv(envp[i]);
 393 #endif
 394
 395         scriptname[len - 1] = '\"';
 396         status = system(scriptname);
 397
 398         free(scriptname);
 399
 400         /* Unset environment */
 401
 402         for(i = 0; envp[i]; i++) {
 403                 char *e = strchr(envp[i], '=');
 404                 if(e) {
 405                         p = alloca(e - envp[i] + 1);
 406                         strncpy(p, envp[i], e - envp[i]);
 407                         p[e - envp[i]] = '\0';
 408                         putenv(p);
 409                 }
 410         }
 411
 412 #ifdef WEXITSTATUS
 413         if(status != -1) {
 414                 if(WIFEXITED(status)) { /* Child exited by itself */
 415                         if(WEXITSTATUS(status)) {
 416                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 417                                            name, WEXITSTATUS(status));
 418                                 return false;
 419                         }
 420                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 421                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 422                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 423                         return false;
 424                 } else {                        /* Something strange happened */
 425                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 426                         return false;
 427                 }
 428         } else {
 429                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 430                 return false;
 431         }
 432 #endif
 433 #endif
 434         return true;
 435 }
 436
 437
 438 /*
 439   Signal handlers.
 440 */
 441
 442 #ifndef HAVE_MINGW
 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 unexpected_signal_handler(int a)
 476 {
 477         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 478         cp_trace();
 479 }
 480
 481 static RETSIGTYPE ignore_signal_handler(int a)
 482 {
 483         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 484 }
 485
 486 static struct {
 487         int signal;
 488         void (*handler)(int);
 489 } sighandlers[] = {
 490         {SIGSEGV, fatal_signal_handler},
 491         {SIGBUS, fatal_signal_handler},
 492         {SIGILL, fatal_signal_handler},
 493         {SIGPIPE, ignore_signal_handler},
 494         {SIGCHLD, ignore_signal_handler},
 495         {0, NULL}
 496 };
 497 #endif
 498
 499 void setup_signals(void)
 500 {
 501 #ifndef HAVE_MINGW
 502         int i;
 503         struct sigaction act;
 504
 505         sigemptyset(&emptysigset);
 506         act.sa_handler = NULL;
 507         act.sa_mask = emptysigset;
 508         act.sa_flags = 0;
 509
 510         /* Set a default signal handler for every signal, errors will be
 511            ignored. */
 512         for(i = 0; i < NSIG; i++) {
 513                 if(!do_detach)
 514                         act.sa_handler = SIG_DFL;
 515                 else
 516                         act.sa_handler = unexpected_signal_handler;
 517                 sigaction(i, &act, NULL);
 518         }
 519
 520         /* If we didn't detach, allow coredumps */
 521         if(!do_detach)
 522                 sighandlers[0].handler = SIG_DFL;
 523
 524         /* Then, for each known signal that we want to catch, assign a
 525            handler to the signal, with error checking this time. */
 526         for(i = 0; sighandlers[i].signal; i++) {
 527                 act.sa_handler = sighandlers[i].handler;
 528                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 529                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 530                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 531                                         strerror(errno));
 532         }
 533 #endif
 534 }