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 void memory_full(int size) {
  49         logger(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size);
  50         cp_trace();
  51         exit(1);
  52 }
  53
  54 /* Some functions the less gifted operating systems might lack... */
  55
  56 #ifdef HAVE_MINGW
  57 extern char *identname;
  58 extern char *program_name;
  59 extern char **g_argv;
  60
  61 static SC_HANDLE manager = NULL;
  62 static SC_HANDLE service = NULL;
  63 static SERVICE_STATUS status = {0};
  64 static SERVICE_STATUS_HANDLE statushandle = 0;
  65
  66 bool install_service(void) {
  67         char command[4096] = "\"";
  68         char **argp;
  69         bool space;
  70         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  71
  72         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  73         if(!manager) {
  74                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
  75                 return false;
  76         }
  77
  78         if(!strchr(program_name, '\\')) {
  79                 GetCurrentDirectory(sizeof command - 1, command + 1);
  80                 strncat(command, "\\", sizeof command - strlen(command));
  81         }
  82
  83         strncat(command, program_name, sizeof command - strlen(command));
  84
  85         strncat(command, "\"", sizeof command - strlen(command));
  86
  87         for(argp = g_argv + 1; *argp; argp++) {
  88                 space = strchr(*argp, ' ');
  89                 strncat(command, " ", sizeof command - strlen(command));
  90
  91                 if(space)
  92                         strncat(command, "\"", sizeof command - strlen(command));
  93
  94                 strncat(command, *argp, sizeof command - strlen(command));
  95
  96                 if(space)
  97                         strncat(command, "\"", sizeof command - strlen(command));
  98         }
  99
 100         service = CreateService(manager, identname, identname,
 101                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 102                         command, NULL, NULL, NULL, NULL, NULL);
 103
 104         if(!service) {
 105                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
 106                 return false;
 107         }
 108
 109         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 110
 111         logger(LOG_INFO, _("%s service installed"), identname);
 112
 113         if(!StartService(service, 0, NULL))
 114                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
 115         else
 116                 logger(LOG_INFO, _("%s service started"), identname);
 117
 118         return true;
 119 }
 120
 121 bool remove_service(void) {
 122         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 123         if(!manager) {
 124                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
 125                 return false;
 126         }
 127
 128         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 129
 130         if(!service) {
 131                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
 132                 return false;
 133         }
 134
 135         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 136                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
 137         else
 138                 logger(LOG_INFO, _("%s service stopped"), identname);
 139
 140         if(!DeleteService(service)) {
 141                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
 142                 return false;
 143         }
 144
 145         logger(LOG_INFO, _("%s service removed"), identname);
 146
 147         return true;
 148 }
 149
 150 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 151         switch(request) {
 152                 case SERVICE_CONTROL_STOP:
 153                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
 154                         break;
 155                 case SERVICE_CONTROL_SHUTDOWN:
 156                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
 157                         break;
 158                 default:
 159                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
 160                         return ERROR_CALL_NOT_IMPLEMENTED;
 161         }
 162
 163         event_loopexit(NULL);
 164         status.dwWaitHint = 30000;
 165         status.dwCurrentState = SERVICE_STOP_PENDING;
 166         SetServiceStatus(statushandle, &status);
 167         return NO_ERROR;
 168 }
 169
 170 VOID WINAPI run_service(DWORD argc, LPTSTR* argv) {
 171         int err = 1;
 172         extern int main2(int argc, char **argv);
 173
 174
 175         status.dwServiceType = SERVICE_WIN32;
 176         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 177         status.dwWin32ExitCode = 0;
 178         status.dwServiceSpecificExitCode = 0;
 179         status.dwCheckPoint = 0;
 180
 181         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 182
 183         if (!statushandle) {
 184                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 185                 err = 1;
 186         } else {
 187                 status.dwWaitHint = 30000;
 188                 status.dwCurrentState = SERVICE_START_PENDING;
 189                 SetServiceStatus(statushandle, &status);
 190
 191                 status.dwWaitHint = 0;
 192                 status.dwCurrentState = SERVICE_RUNNING;
 193                 SetServiceStatus(statushandle, &status);
 194
 195                 err = main2(argc, argv);
 196
 197                 status.dwWaitHint = 0;
 198                 status.dwCurrentState = SERVICE_STOPPED;
 199                 //status.dwWin32ExitCode = err;
 200                 SetServiceStatus(statushandle, &status);
 201         }
 202
 203         return;
 204 }
 205
 206 bool init_service(void) {
 207         SERVICE_TABLE_ENTRY services[] = {
 208                 {identname, run_service},
 209                 {NULL, NULL}
 210         };
 211
 212         if(!StartServiceCtrlDispatcher(services)) {
 213                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 214                         return false;
 215                 }
 216                 else
 217                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
 218         }
 219
 220         return true;
 221 }
 222 #endif
 223
 224 #ifndef HAVE_MINGW
 225 /*
 226   check for an existing tinc for this net, and write pid to pidfile
 227 */
 228 static bool write_pidfile(void) {
 229         pid_t pid;
 230
 231         cp();
 232
 233         pid = check_pid(pidfilename);
 234
 235         if(pid) {
 236                 if(netname)
 237                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
 238                                         netname, (long)pid);
 239                 else
 240                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
 241                 return false;
 242         }
 243
 244         /* if it's locked, write-protected, or whatever */
 245         if(!write_pid(pidfilename)) {
 246                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
 247                 return false;
 248         }
 249
 250         return true;
 251 }
 252 #endif
 253
 254 /*
 255   kill older tincd for this net
 256 */
 257 bool kill_other(int signal) {
 258 #ifndef HAVE_MINGW
 259         pid_t pid;
 260
 261         cp();
 262
 263         pid = read_pid(pidfilename);
 264
 265         if(!pid) {
 266                 if(netname)
 267                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
 268                                         netname);
 269                 else
 270                         fprintf(stderr, _("No other tincd is running.\n"));
 271                 return false;
 272         }
 273
 274         errno = 0;                                      /* No error, sometimes errno is only changed on error */
 275
 276         /* ESRCH is returned when no process with that pid is found */
 277         if(kill(pid, signal) && errno == ESRCH) {
 278                 if(netname)
 279                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
 280                                         netname);
 281                 else
 282                         fprintf(stderr, _("The tincd is no longer running. "));
 283
 284                 fprintf(stderr, _("Removing stale lock file.\n"));
 285                 remove_pid(pidfilename);
 286         }
 287
 288         return true;
 289 #else
 290         return remove_service();
 291 #endif
 292 }
 293
 294 /*
 295   Detach from current terminal, write pidfile, kill parent
 296 */
 297 bool detach(void) {
 298         cp();
 299
 300         setup_signals();
 301
 302         /* First check if we can open a fresh new pidfile */
 303
 304 #ifndef HAVE_MINGW
 305         if(!write_pidfile())
 306                 return false;
 307
 308         /* If we succeeded in doing that, detach */
 309
 310         closelogger();
 311 #endif
 312
 313         if(do_detach) {
 314 #ifndef HAVE_MINGW
 315                 if(daemon(0, 0)) {
 316                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
 317                                         strerror(errno));
 318                         return false;
 319                 }
 320
 321                 /* Now UPDATE the pid in the pidfile, because we changed it... */
 322
 323                 if(!write_pid(pidfilename)) {
 324                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
 325                         return false;
 326                 }
 327 #else
 328                 if(!statushandle)
 329                         exit(install_service());
 330 #endif
 331         }
 332
 333         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 334
 335         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
 336                            VERSION, __DATE__, __TIME__, debug_level);
 337
 338         xalloc_fail_func = memory_full;
 339
 340         return true;
 341 }
 342
 343 bool execute_script(const char *name, char **envp) {
 344 #ifdef HAVE_SYSTEM
 345         int status, len;
 346         struct stat s;
 347         char *scriptname, *p;
 348         int i;
 349
 350         cp();
 351
 352 #ifndef HAVE_MINGW
 353         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
 354 #else
 355         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 356 #endif
 357         if(len < 0)
 358                 return false;
 359
 360         scriptname[len - 1] = '\0';
 361
 362         /* First check if there is a script */
 363
 364         if(stat(scriptname + 1, &s)) {
 365                 free(scriptname);
 366                 return true;
 367         }
 368
 369         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
 370
 371 #ifdef HAVE_PUTENV
 372         /* Set environment */
 373
 374         for(i = 0; envp[i]; i++)
 375                 putenv(envp[i]);
 376 #endif
 377
 378         scriptname[len - 1] = '\"';
 379         status = system(scriptname);
 380
 381         free(scriptname);
 382
 383         /* Unset environment */
 384
 385         for(i = 0; envp[i]; i++) {
 386                 char *e = strchr(envp[i], '=');
 387                 if(e) {
 388                         p = alloca(e - envp[i] + 1);
 389                         strncpy(p, envp[i], e - envp[i]);
 390                         p[e - envp[i]] = '\0';
 391                         putenv(p);
 392                 }
 393         }
 394
 395 #ifdef WEXITSTATUS
 396         if(status != -1) {
 397                 if(WIFEXITED(status)) { /* Child exited by itself */
 398                         if(WEXITSTATUS(status)) {
 399                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
 400                                            name, WEXITSTATUS(status));
 401                                 return false;
 402                         }
 403                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 404                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
 405                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 406                         return false;
 407                 } else {                        /* Something strange happened */
 408                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
 409                         return false;
 410                 }
 411         } else {
 412                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
 413                 return false;
 414         }
 415 #endif
 416 #endif
 417         return true;
 418 }
 419
 420
 421 /*
 422   Signal handlers.
 423 */
 424
 425 #ifndef HAVE_MINGW
 426 static RETSIGTYPE fatal_signal_square(int a) {
 427         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
 428                    strsignal(a));
 429         cp_trace();
 430         exit(1);
 431 }
 432
 433 static RETSIGTYPE fatal_signal_handler(int a) {
 434         struct sigaction act;
 435         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
 436         cp_trace();
 437
 438         if(do_detach) {
 439                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
 440
 441                 act.sa_handler = fatal_signal_square;
 442                 act.sa_mask = emptysigset;
 443                 act.sa_flags = 0;
 444                 sigaction(SIGSEGV, &act, NULL);
 445
 446                 close_network_connections();
 447                 sleep(5);
 448                 remove_pid(pidfilename);
 449                 execvp(g_argv[0], g_argv);
 450         } else {
 451                 logger(LOG_NOTICE, _("Not restarting."));
 452                 exit(1);
 453         }
 454 }
 455
 456 static RETSIGTYPE unexpected_signal_handler(int a) {
 457         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
 458         cp_trace();
 459 }
 460
 461 static RETSIGTYPE ignore_signal_handler(int a) {
 462         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
 463 }
 464
 465 static struct {
 466         int signal;
 467         void (*handler)(int);
 468 } sighandlers[] = {
 469         {SIGSEGV, fatal_signal_handler},
 470         {SIGBUS, fatal_signal_handler},
 471         {SIGILL, fatal_signal_handler},
 472         {SIGPIPE, ignore_signal_handler},
 473         {SIGCHLD, ignore_signal_handler},
 474         {0, NULL}
 475 };
 476 #endif
 477
 478 void setup_signals(void) {
 479 #ifndef HAVE_MINGW
 480         int i;
 481         struct sigaction act;
 482
 483         sigemptyset(&emptysigset);
 484         act.sa_handler = NULL;
 485         act.sa_mask = emptysigset;
 486         act.sa_flags = 0;
 487
 488         /* Set a default signal handler for every signal, errors will be
 489            ignored. */
 490         for(i = 0; i < NSIG; i++) {
 491                 if(!do_detach)
 492                         act.sa_handler = SIG_DFL;
 493                 else
 494                         act.sa_handler = unexpected_signal_handler;
 495                 sigaction(i, &act, NULL);
 496         }
 497
 498         /* If we didn't detach, allow coredumps */
 499         if(!do_detach)
 500                 sighandlers[0].handler = SIG_DFL;
 501
 502         /* Then, for each known signal that we want to catch, assign a
 503            handler to the signal, with error checking this time. */
 504         for(i = 0; sighandlers[i].signal; i++) {
 505                 act.sa_handler = sighandlers[i].handler;
 506                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 507                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
 508                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 509                                         strerror(errno));
 510         }
 511 #endif
 512 }