tinc-vpn.org Git - tinc/blob - src/process.c

   1 /*
   2     process.c -- process management functions
   3     Copyright (C) 1999-2005 Ivo Timmermans,
   4                   2000-2009 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                 logger(LOG_ERR, "Could not create %s service: %s", identname, winerror(GetLastError()));
 102                 return false;
 103         }
 104
 105         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
 106
 107         logger(LOG_INFO, "%s service installed", identname);
 108
 109         if(!StartService(service, 0, NULL))
 110                 logger(LOG_WARNING, "Could not start %s service: %s", identname, winerror(GetLastError()));
 111         else
 112                 logger(LOG_INFO, "%s service started", identname);
 113
 114         return true;
 115 }
 116
 117 bool remove_service(void) {
 118         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
 119         if(!manager) {
 120                 logger(LOG_ERR, "Could not open service manager: %s", winerror(GetLastError()));
 121                 return false;
 122         }
 123
 124         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
 125
 126         if(!service) {
 127                 logger(LOG_ERR, "Could not open %s service: %s", identname, winerror(GetLastError()));
 128                 return false;
 129         }
 130
 131         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
 132                 logger(LOG_ERR, "Could not stop %s service: %s", identname, winerror(GetLastError()));
 133         else
 134                 logger(LOG_INFO, "%s service stopped", identname);
 135
 136         if(!DeleteService(service)) {
 137                 logger(LOG_ERR, "Could not remove %s service: %s", identname, winerror(GetLastError()));
 138                 return false;
 139         }
 140
 141         logger(LOG_INFO, "%s service removed", identname);
 142
 143         return true;
 144 }
 145
 146 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
 147         switch(request) {
 148                 case SERVICE_CONTROL_INTERROGATE:
 149                         SetServiceStatus(statushandle, &status);
 150                         return NO_ERROR;
 151                 case SERVICE_CONTROL_STOP:
 152                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_STOP");
 153                         break;
 154                 case SERVICE_CONTROL_SHUTDOWN:
 155                         logger(LOG_NOTICE, "Got %s request", "SERVICE_CONTROL_SHUTDOWN");
 156                         break;
 157                 default:
 158                         logger(LOG_WARNING, "Got unexpected request %d", request);
 159                         return ERROR_CALL_NOT_IMPLEMENTED;
 160         }
 161
 162         event_loopexit(NULL);
 163         status.dwWaitHint = 30000;
 164         status.dwCurrentState = SERVICE_STOP_PENDING;
 165         SetServiceStatus(statushandle, &status);
 166         return NO_ERROR;
 167 }
 168
 169 VOID WINAPI run_service(DWORD argc, LPTSTR* argv) {
 170         int err = 1;
 171         extern int main2(int argc, char **argv);
 172
 173
 174         status.dwServiceType = SERVICE_WIN32;
 175         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 176         status.dwWin32ExitCode = 0;
 177         status.dwServiceSpecificExitCode = 0;
 178         status.dwCheckPoint = 0;
 179
 180         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL);
 181
 182         if (!statushandle) {
 183                 logger(LOG_ERR, "System call `%s' failed: %s", "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
 184                 err = 1;
 185         } else {
 186                 status.dwWaitHint = 30000;
 187                 status.dwCurrentState = SERVICE_START_PENDING;
 188                 SetServiceStatus(statushandle, &status);
 189
 190                 status.dwWaitHint = 0;
 191                 status.dwCurrentState = SERVICE_RUNNING;
 192                 SetServiceStatus(statushandle, &status);
 193
 194                 err = main2(argc, argv);
 195
 196                 status.dwWaitHint = 0;
 197                 status.dwCurrentState = SERVICE_STOPPED;
 198                 //status.dwWin32ExitCode = err;
 199                 SetServiceStatus(statushandle, &status);
 200         }
 201
 202         return;
 203 }
 204
 205 bool init_service(void) {
 206         SERVICE_TABLE_ENTRY services[] = {
 207                 {identname, run_service},
 208                 {NULL, NULL}
 209         };
 210
 211         if(!StartServiceCtrlDispatcher(services)) {
 212                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
 213                         return false;
 214                 }
 215                 else
 216                         logger(LOG_ERR, "System call `%s' failed: %s", "StartServiceCtrlDispatcher", winerror(GetLastError()));
 217         }
 218
 219         return true;
 220 }
 221 #endif
 222
 223 /*
 224   Detach from current terminal
 225 */
 226 bool detach(void) {
 227         setup_signals();
 228
 229 #ifndef HAVE_MINGW
 230         closelogger();
 231 #endif
 232
 233         if(do_detach) {
 234 #ifndef HAVE_MINGW
 235                 if(daemon(0, 0)) {
 236                         fprintf(stderr, "Couldn't detach from terminal: %s",
 237                                         strerror(errno));
 238                         return false;
 239                 }
 240 #else
 241                 if(!statushandle)
 242                         exit(install_service());
 243 #endif
 244         }
 245
 246         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
 247
 248         logger(LOG_NOTICE, "tincd %s (%s %s) starting, debug level %d",
 249                            VERSION, __DATE__, __TIME__, debug_level);
 250
 251         xalloc_fail_func = memory_full;
 252
 253         return true;
 254 }
 255
 256 bool execute_script(const char *name, char **envp) {
 257 #ifdef HAVE_SYSTEM
 258         int status, len;
 259         char *scriptname, *p;
 260         int i;
 261
 262 #ifndef HAVE_MINGW
 263         len = xasprintf(&scriptname, "\"%s/%s\"", confbase, name);
 264 #else
 265         len = xasprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
 266 #endif
 267         if(len < 0)
 268                 return false;
 269
 270         scriptname[len - 1] = '\0';
 271
 272 #ifndef HAVE_TUNEMU
 273         /* First check if there is a script */
 274
 275         if(access(scriptname + 1, F_OK)) {
 276                 free(scriptname);
 277                 return true;
 278         }
 279 #endif
 280
 281         ifdebug(STATUS) logger(LOG_INFO, "Executing script %s", name);
 282
 283 #ifdef HAVE_PUTENV
 284         /* Set environment */
 285
 286         for(i = 0; envp[i]; i++)
 287                 putenv(envp[i]);
 288 #endif
 289
 290         scriptname[len - 1] = '\"';
 291         status = system(scriptname);
 292
 293         free(scriptname);
 294
 295         /* Unset environment */
 296
 297         for(i = 0; envp[i]; i++) {
 298                 char *e = strchr(envp[i], '=');
 299                 if(e) {
 300                         p = alloca(e - envp[i] + 1);
 301                         strncpy(p, envp[i], e - envp[i]);
 302                         p[e - envp[i]] = '\0';
 303                         putenv(p);
 304                 }
 305         }
 306
 307 #ifdef WEXITSTATUS
 308         if(status != -1) {
 309                 if(WIFEXITED(status)) { /* Child exited by itself */
 310                         if(WEXITSTATUS(status)) {
 311                                 logger(LOG_ERR, "Script %s exited with non-zero status %d",
 312                                            name, WEXITSTATUS(status));
 313                                 return false;
 314                         }
 315                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
 316                         logger(LOG_ERR, "Script %s was killed by signal %d (%s)",
 317                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
 318                         return false;
 319                 } else {                        /* Something strange happened */
 320                         logger(LOG_ERR, "Script %s terminated abnormally", name);
 321                         return false;
 322                 }
 323         } else {
 324                 logger(LOG_ERR, "System call `%s' failed: %s", "system", strerror(errno));
 325                 return false;
 326         }
 327 #endif
 328 #endif
 329         return true;
 330 }
 331
 332
 333 /*
 334   Signal handlers.
 335 */
 336
 337 #ifndef HAVE_MINGW
 338 static RETSIGTYPE fatal_signal_square(int a) {
 339         logger(LOG_ERR, "Got another fatal signal %d (%s): not restarting.", a,
 340                    strsignal(a));
 341         exit(1);
 342 }
 343
 344 static RETSIGTYPE fatal_signal_handler(int a) {
 345         struct sigaction act;
 346         logger(LOG_ERR, "Got fatal signal %d (%s)", a, strsignal(a));
 347
 348         if(do_detach) {
 349                 logger(LOG_NOTICE, "Trying to re-execute in 5 seconds...");
 350
 351                 act.sa_handler = fatal_signal_square;
 352                 act.sa_mask = emptysigset;
 353                 act.sa_flags = 0;
 354                 sigaction(SIGSEGV, &act, NULL);
 355
 356                 close_network_connections();
 357                 sleep(5);
 358                 exit_control();
 359                 execvp(g_argv[0], g_argv);
 360         } else {
 361                 logger(LOG_NOTICE, "Not restarting.");
 362                 exit(1);
 363         }
 364 }
 365
 366 static RETSIGTYPE unexpected_signal_handler(int a) {
 367         logger(LOG_WARNING, "Got unexpected signal %d (%s)", a, strsignal(a));
 368 }
 369
 370 static RETSIGTYPE ignore_signal_handler(int a) {
 371         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Ignored signal %d (%s)", a, strsignal(a));
 372 }
 373
 374 static struct {
 375         int signal;
 376         void (*handler)(int);
 377 } sighandlers[] = {
 378         {SIGSEGV, fatal_signal_handler},
 379         {SIGBUS, fatal_signal_handler},
 380         {SIGILL, fatal_signal_handler},
 381         {SIGPIPE, ignore_signal_handler},
 382         {SIGCHLD, ignore_signal_handler},
 383         {0, NULL}
 384 };
 385 #endif
 386
 387 void setup_signals(void) {
 388 #ifndef HAVE_MINGW
 389         int i;
 390         struct sigaction act;
 391
 392         sigemptyset(&emptysigset);
 393         act.sa_handler = NULL;
 394         act.sa_mask = emptysigset;
 395         act.sa_flags = 0;
 396
 397         /* Set a default signal handler for every signal, errors will be
 398            ignored. */
 399         for(i = 1; i < NSIG; i++) {
 400                 if(!do_detach)
 401                         act.sa_handler = SIG_DFL;
 402                 else
 403                         act.sa_handler = unexpected_signal_handler;
 404                 sigaction(i, &act, NULL);
 405         }
 406
 407         /* If we didn't detach, allow coredumps */
 408         if(!do_detach)
 409                 sighandlers[0].handler = SIG_DFL;
 410
 411         /* Then, for each known signal that we want to catch, assign a
 412            handler to the signal, with error checking this time. */
 413         for(i = 0; sighandlers[i].signal; i++) {
 414                 act.sa_handler = sighandlers[i].handler;
 415                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
 416                         fprintf(stderr, "Installing signal handler for signal %d (%s) failed: %s\n",
 417                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
 418                                         strerror(errno));
 419         }
 420 #endif
 421 }