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 "control.h"
  26 #include "device.h"
  27 #include "edge.h"
  28 #include "logger.h"
  29 #include "node.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 sigalrm = false;
  38
  39 extern char *identname;
  40 extern char **g_argv;
  41 extern bool use_logfile;
  42
  43 #ifndef HAVE_MINGW
  44 sigset_t emptysigset;
  45 #endif
  46
  47 static void memory_full(int size) {
  48         logger(LOG_ERR, "Memory exhausted (couldn't allocate %d bytes), exitting.", size);
  49         exit(1);
  50 }
  51
  52 /* Some functions the less gifted operating systems might lack... */
  53
  54 #ifdef HAVE_MINGW
  55 extern char *identname;
  56 extern char *program_name;
  57 extern char **g_argv;
  58
  59 static SC_HANDLE manager = NULL;
  60 static SC_HANDLE service = NULL;
  61 static SERVICE_STATUS status = {0};
  62 static SERVICE_STATUS_HANDLE statushandle = 0;
  63
  64 bool install_service(void) {
  65         char command[4096] = "\"";
  66         char **argp;
  67         bool space;
  68         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
  69
  70         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
  71         if(!manager) {
  72                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
  73                 return false;
  74         }
  75
  76         if(!strchr(program_name, '\\')) {
  77                 GetCurrentDirectory(sizeof command - 1, command + 1);
  78                 strncat(command, "\\", sizeof command - strlen(command));
  79         }
  80
  81         strncat(command, program_name, sizeof command - strlen(command));
  82
  83         strncat(command, "\"", sizeof command - strlen(command));
  84
  85         for(argp = g_argv + 1; *argp; argp++) {
  86                 space = strchr(*argp, ' ');
  87                 strncat(command, " ", sizeof command - strlen(command));
  88
  89                 if(space)
  90                         strncat(command, "\"", sizeof command - strlen(command));
  91
  92                 strncat(command, *argp, sizeof command - strlen(command));
  93
  94                 if(space)
  95                         strncat(command, "\"", sizeof command - strlen(command));
  96         }
  97
  98         service = CreateService(manager, identname, identname,
  99                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
 100                         command, NULL, NULL, NULL, NULL, NULL);
 101
 102         if(!service) {
 103                 DWORD lasterror = GetLastError();
 104                 logger(LOG_ERR, "Could not create %s service: %s", identname, winerror(lasterror));
 105                 if(lasterror != ERROR_SERVICE_EXISTS)
 106                         return false;
 107         }
 108
 109         if(service) {
 110                 ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 111                 logger(LOG_INFO, "%s service installed", identname);
 112         } else {
 113                 service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 114         }
 115
 116         if(!StartService(service, 0, NULL))
 117                 logger(LOG_WARNING, "Could not start %s service: %s", identname, winerror(GetLastError()));
 118         else
 119                 logger(LOG_INFO, "%s service started", identname);
 120
 121         return true;
 122 }
 123
 124 bool remove_service(void) {
 125         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 126         if(!manager) {
 127                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
 128                 return false;
 129         }
 130
 131         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 132
 133         if(!service) {
 134                 logger(LOG_ERR, "Could not open %s service: %s", identname, winerror(GetLastError()));
 135                 return false;
 136         }
 137
 138         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 139                 logger(LOG_ERR, "Could not stop %s service: %s", identname, winerror(GetLastError()));
 140         else
 141                 logger(LOG_INFO, "%s service stopped", identname);
 142
 143         if(!DeleteService(service)) {
 144                 logger(LOG_ERR, "Could not remove %s service: %s", identname, winerror(GetLastError()));
 145                 return false;
 146         }
 147
 148         logger(LOG_INFO, "%s service removed", identname);
 149
 150         return true;
 151 }
 152
 153 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 154         switch(request) {
 155                 case SERVICE_CONTROL_INTERROGATE:
 156                         SetServiceStatus(statushandle, &status);
 157                         return NO_ERROR;
 158                 case SERVICE_CONTROL_STOP:
 159                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_STOP");
 160                         break;
 161                 case SERVICE_CONTROL_SHUTDOWN:
 162                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_SHUTDOWN");
 163                         break;
 164                 default:
 165                         logger(LOG_WARNING, "Got unexpected request %d", request);
 166                         return ERROR_CALL_NOT_IMPLEMENTED;
 167         }
 168
 169         abort();
 170         status.dwWaitHint = 30000;
 171         status.dwCurrentState = SERVICE_STOP_PENDING;
 172         SetServiceStatus(statushandle, &status);
 173         return NO_ERROR;
 174 }
 175
 176 VOID WINAPI run_service(DWORD argc, LPTSTR* argv) {
 177         int err = 1;
 178         extern int main2(int argc, char **argv);
 179
 180
 181         status.dwServiceType = SERVICE_WIN32;
 182         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 183         status.dwWin32ExitCode = 0;
 184         status.dwServiceSpecificExitCode = 0;
 185         status.dwCheckPoint = 0;
 186
 187         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 188
 189         if (!statushandle) {
 190                 logger(LOG_ERR, "System call `%s' failed: %s", "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 191                 err = 1;
 192         } else {
 193                 status.dwWaitHint = 30000;
 194                 status.dwCurrentState = SERVICE_START_PENDING;
 195                 SetServiceStatus(statushandle, &status);
 196
 197                 status.dwWaitHint = 0;
 198                 status.dwCurrentState = SERVICE_RUNNING;
 199                 SetServiceStatus(statushandle, &status);
 200
 201                 err = main2(argc, argv);
 202
 203                 status.dwWaitHint = 0;
 204                 status.dwCurrentState = SERVICE_STOPPED;
 205                 //status.dwWin32ExitCode = err;
 206                 SetServiceStatus(statushandle, &status);
 207         }
 208
 209         return;
 210 }
 211
 212 bool init_service(void) {
 213         SERVICE_TABLE_ENTRY services[] = {
 214                 {identname, run_service},
 215                 {NULL, NULL}
 216         };
 217
 218         if(!StartServiceCtrlDispatcher(services)) {
 219                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 220                         return false;
 221                 }
 222                 else
 223                         logger(LOG_ERR, "System call `%s' failed: %s", "StartServiceCtrlDispatcher", winerror(GetLastError()));
 224         }
 225
 226         return true;
 227 }
 228 #endif
 229
 230 /*
 231   Detach from current terminal
 232 */
 233 bool detach(void) {
 234         setup_signals();
 235
 236 #ifndef HAVE_MINGW
 237         closelogger();
 238 #endif
 239
 240         if(do_detach) {
 241 #ifndef HAVE_MINGW
 242                 if(daemon(0, 0)) {
 243                         fprintf(stderr, "Couldn't detach from terminal: %s",
 244                                         strerror(errno));
 245                         return false;
 246                 }
 247 #else
 248                 if(!statushandle)
 249                         exit(install_service());
 250 #endif
 251         }
 252
 253         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 254
 255         logger(LOG_NOTICE, "tincd %s (%s %s) starting, debug level %d",
 256                            VERSION, __DATE__, __TIME__, debug_level);
 257
 258         xalloc_fail_func = memory_full;
 259
 260         return true;
 261 }
 262
 263 bool execute_script(const char *name, char **envp) {
 264 #ifdef HAVE_SYSTEM
 265         int status, len;
 266         char *scriptname;
 267         int i;
 268
 269 #ifndef HAVE_MINGW
 270         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 271 #else
 272         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 273 #endif
 274         if(len < 0)
 275                 return false;
 276
 277         scriptname[len - 1] = '\0';
 278
 279 #ifndef HAVE_TUNEMU
 280         /* First check if there is a script */
 281
 282         if(access(scriptname + 1, F_OK)) {
 283                 free(scriptname);
 284                 return true;
 285         }
 286 #endif
 287
 288         ifdebug(STATUS) logger(LOG_INFO, "Executing script %s", name);
 289
 290 #ifdef HAVE_PUTENV
 291         /* Set environment */
 292
 293         for(i = 0; envp[i]; i++)
 294                 putenv(envp[i]);
 295 #endif
 296
 297         scriptname[len - 1] = '\"';
 298         status = system(scriptname);
 299
 300         free(scriptname);
 301
 302         /* Unset environment */
 303
 304         for(i = 0; envp[i]; i++) {
 305                 char *e = strchr(envp[i], '=');
 306                 if(e) {
 307                         char p[e - envp[i] + 1];
 308                         strncpy(p, envp[i], e - envp[i]);
 309                         p[e - envp[i]] = '\0';
 310                         putenv(p);
 311                 }
 312         }
 313
 314 #ifdef WEXITSTATUS
 315         if(status != -1) {
 316                 if(WIFEXITED(status)) { /* Child exited by itself */
 317                         if(WEXITSTATUS(status)) {
 318                                 logger(LOG_ERR, "Script %s exited with non-zero status %d",
 319                                            name, WEXITSTATUS(status));
 320                                 return false;
 321                         }
 322                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 323                         logger(LOG_ERR, "Script %s was killed by signal %d (%s)",
 324                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 325                         return false;
 326                 } else {                        /* Something strange happened */
 327                         logger(LOG_ERR, "Script %s terminated abnormally", name);
 328                         return false;
 329                 }
 330         } else {
 331                 logger(LOG_ERR, "System call `%s' failed: %s", "system", strerror(errno));
 332                 return false;
 333         }
 334 #endif
 335 #endif
 336         return true;
 337 }
 338
 339
 340 /*
 341   Signal handlers.
 342 */
 343
 344 #ifndef HAVE_MINGW
 345 static RETSIGTYPE sigterm_handler(int a) {
 346         logger(LOG_NOTICE, "Got %s signal", "TERM");
 347         if(running)
 348                 running = false;
 349         else
 350                 exit(1);
 351 }
 352
 353 static RETSIGTYPE fatal_signal_square(int a) {
 354         logger(LOG_ERR, "Got another fatal signal %d (%s): not restarting.", a,
 355                    strsignal(a));
 356         exit(1);
 357 }
 358
 359 static RETSIGTYPE fatal_signal_handler(int a) {
 360         struct sigaction act;
 361         logger(LOG_ERR, "Got fatal signal %d (%s)", a, strsignal(a));
 362
 363         if(do_detach) {
 364                 logger(LOG_NOTICE, "Trying to re-execute in 5 seconds...");
 365
 366                 act.sa_handler = fatal_signal_square;
 367                 act.sa_mask = emptysigset;
 368                 act.sa_flags = 0;
 369                 sigaction(SIGSEGV, &act, NULL);
 370
 371                 close_network_connections();
 372                 sleep(5);
 373                 exit_control();
 374                 execvp(g_argv[0], g_argv);
 375         } else {
 376                 logger(LOG_NOTICE, "Not restarting.");
 377                 exit(1);
 378         }
 379 }
 380
 381 static RETSIGTYPE unexpected_signal_handler(int a) {
 382         logger(LOG_WARNING, "Got unexpected signal %d (%s)", a, strsignal(a));
 383 }
 384
 385 static RETSIGTYPE ignore_signal_handler(int a) {
 386         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignored signal %d (%s)", a, strsignal(a));
 387 }
 388
 389 static struct {
 390         int signal;
 391         void (*handler)(int);
 392 } sighandlers[] = {
 393         {SIGTERM, sigterm_handler},
 394         {SIGQUIT, sigterm_handler},
 395         {SIGINT, sigterm_handler},
 396         {SIGSEGV, fatal_signal_handler},
 397         {SIGBUS, fatal_signal_handler},
 398         {SIGILL, fatal_signal_handler},
 399         {SIGPIPE, ignore_signal_handler},
 400         {SIGCHLD, ignore_signal_handler},
 401         {SIGALRM, ignore_signal_handler},
 402         {0, NULL}
 403 };
 404 #endif
 405
 406 void setup_signals(void) {
 407 #ifndef HAVE_MINGW
 408         int i;
 409         struct sigaction act;
 410
 411         sigemptyset(&emptysigset);
 412         act.sa_handler = NULL;
 413         act.sa_mask = emptysigset;
 414         act.sa_flags = 0;
 415
 416         /* Set a default signal handler for every signal, errors will be
 417            ignored. */
 418         for(i = 1; i < NSIG; i++) {
 419                 if(!do_detach)
 420                         act.sa_handler = SIG_DFL;
 421                 else
 422                         act.sa_handler = unexpected_signal_handler;
 423                 sigaction(i, &act, NULL);
 424         }
 425
 426         /* If we didn't detach, allow coredumps */
 427         if(!do_detach)
 428                 sighandlers[0].handler = SIG_DFL;
 429
 430         /* Then, for each known signal that we want to catch, assign a
 431            handler to the signal, with error checking this time. */
 432         for(i = 0; sighandlers[i].signal; i++) {
 433                 act.sa_handler = sighandlers[i].handler;
 434                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 435                         fprintf(stderr, "Installing signal handler for signal %d (%s) failed: %s\n",
 436                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 437                                         strerror(errno));
 438         }
 439 #endif
 440 }