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