Handle SERVICE_CONTROL_INTERROGATE requests. Thanks to Carsten Ralle for noticing...
[tinc] / 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 sighup = false;
40 bool sigalrm = false;
41
42 extern char *identname;
43 extern char *pidfilename;
44 extern char **g_argv;
45 extern bool use_logfile;
46 extern volatile bool running;
47
48 sigset_t emptysigset;
49
50 static int saved_debug_level = -1;
51
52 static void memory_full(int size)
53 {
54         logger(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size);
55         cp_trace();
56         exit(1);
57 }
58
59 /* Some functions the less gifted operating systems might lack... */
60
61 #ifdef HAVE_MINGW
62 extern char *identname;
63 extern char *program_name;
64 extern char **g_argv;
65
66 static SC_HANDLE manager = NULL;
67 static SC_HANDLE service = NULL;
68 static SERVICE_STATUS status = {0};
69 static SERVICE_STATUS_HANDLE statushandle = 0;
70
71 bool install_service(void) {
72         char command[4096] = "\"";
73         char **argp;
74         bool space;
75         SERVICE_DESCRIPTION description = {"Virtual Private Network daemon"};
76
77         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
78         if(!manager) {
79                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
80                 return false;
81         }
82
83         if(!strchr(program_name, '\\')) {
84                 GetCurrentDirectory(sizeof command - 1, command + 1);
85                 strncat(command, "\\", sizeof command - strlen(command));
86         }
87
88         strncat(command, program_name, sizeof command - strlen(command));
89
90         strncat(command, "\"", sizeof command - strlen(command));
91
92         for(argp = g_argv + 1; *argp; argp++) {
93                 space = strchr(*argp, ' ');
94                 strncat(command, " ", sizeof command - strlen(command));
95                 
96                 if(space)
97                         strncat(command, "\"", sizeof command - strlen(command));
98                 
99                 strncat(command, *argp, sizeof command - strlen(command));
100
101                 if(space)
102                         strncat(command, "\"", sizeof command - strlen(command));
103         }
104
105         service = CreateService(manager, identname, identname,
106                         SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS, SERVICE_AUTO_START, SERVICE_ERROR_NORMAL,
107                         command, NULL, NULL, NULL, NULL, NULL);
108         
109         if(!service) {
110                 logger(LOG_ERR, _("Could not create %s service: %s"), identname, winerror(GetLastError()));
111                 return false;
112         }
113
114         ChangeServiceConfig2(service, SERVICE_CONFIG_DESCRIPTION, &description);
115
116         logger(LOG_INFO, _("%s service installed"), identname);
117
118         if(!StartService(service, 0, NULL))
119                 logger(LOG_WARNING, _("Could not start %s service: %s"), identname, winerror(GetLastError()));
120         else
121                 logger(LOG_INFO, _("%s service started"), identname);
122
123         return true;
124 }
125
126 bool remove_service(void) {
127         manager = OpenSCManager(NULL, NULL, SC_MANAGER_ALL_ACCESS);
128         if(!manager) {
129                 logger(LOG_ERR, _("Could not open service manager: %s"), winerror(GetLastError()));
130                 return false;
131         }
132
133         service = OpenService(manager, identname, SERVICE_ALL_ACCESS);
134
135         if(!service) {
136                 logger(LOG_ERR, _("Could not open %s service: %s"), identname, winerror(GetLastError()));
137                 return false;
138         }
139
140         if(!ControlService(service, SERVICE_CONTROL_STOP, &status))
141                 logger(LOG_ERR, _("Could not stop %s service: %s"), identname, winerror(GetLastError()));
142         else
143                 logger(LOG_INFO, _("%s service stopped"), identname);
144
145         if(!DeleteService(service)) {
146                 logger(LOG_ERR, _("Could not remove %s service: %s"), identname, winerror(GetLastError()));
147                 return false;
148         }
149
150         logger(LOG_INFO, _("%s service removed"), identname);
151
152         return true;
153 }
154
155 DWORD WINAPI controlhandler(DWORD request, DWORD type, LPVOID boe, LPVOID bah) {
156         switch(request) {
157                 case SERVICE_CONTROL_INTERROGATE:
158                         SetServiceStatus(statushandle, &status);
159                         return NO_ERROR;
160                 case SERVICE_CONTROL_STOP:
161                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_STOP");
162                         break;
163                 case SERVICE_CONTROL_SHUTDOWN:
164                         logger(LOG_NOTICE, _("Got %s request"), "SERVICE_CONTROL_SHUTDOWN");
165                         break;
166                 default:
167                         logger(LOG_WARNING, _("Got unexpected request %d"), request);
168                         return ERROR_CALL_NOT_IMPLEMENTED;
169         }
170
171         if(running) {
172                 running = false;
173                 status.dwWaitHint = 30000; 
174                 status.dwCurrentState = SERVICE_STOP_PENDING; 
175                 SetServiceStatus(statushandle, &status);
176                 return NO_ERROR;
177         } else {
178                 status.dwWaitHint = 0; 
179                 status.dwCurrentState = SERVICE_STOPPED; 
180                 SetServiceStatus(statushandle, &status);
181                 exit(1);
182         }
183
184 }
185
186 VOID WINAPI run_service(DWORD argc, LPTSTR* argv)
187 {
188         int err = 1;
189         extern int main2(int argc, char **argv);
190
191
192         status.dwServiceType = SERVICE_WIN32; 
193         status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
194         status.dwWin32ExitCode = 0; 
195         status.dwServiceSpecificExitCode = 0; 
196         status.dwCheckPoint = 0; 
197
198         statushandle = RegisterServiceCtrlHandlerEx(identname, controlhandler, NULL); 
199
200         if (!statushandle) {
201                 logger(LOG_ERR, _("System call `%s' failed: %s"), "RegisterServiceCtrlHandlerEx", winerror(GetLastError()));
202                 err = 1;
203         } else {
204                 status.dwWaitHint = 30000; 
205                 status.dwCurrentState = SERVICE_START_PENDING; 
206                 SetServiceStatus(statushandle, &status);
207
208                 status.dwWaitHint = 0; 
209                 status.dwCurrentState = SERVICE_RUNNING;
210                 SetServiceStatus(statushandle, &status);
211
212                 err = main2(argc, argv);
213
214                 status.dwWaitHint = 0;
215                 status.dwCurrentState = SERVICE_STOPPED; 
216                 //status.dwWin32ExitCode = err; 
217                 SetServiceStatus(statushandle, &status);
218         }
219
220         return;
221 }
222
223 bool init_service(void) {
224         SERVICE_TABLE_ENTRY services[] = {
225                 {identname, run_service},
226                 {NULL, NULL}
227         };
228
229         if(!StartServiceCtrlDispatcher(services)) {
230                 if(GetLastError() == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
231                         return false;
232                 }
233                 else
234                         logger(LOG_ERR, _("System call `%s' failed: %s"), "StartServiceCtrlDispatcher", winerror(GetLastError()));
235         }
236
237         return true;
238 }
239 #endif
240
241 #ifndef HAVE_MINGW
242 /*
243   check for an existing tinc for this net, and write pid to pidfile
244 */
245 static bool write_pidfile(void)
246 {
247         pid_t pid;
248
249         cp();
250
251         pid = check_pid(pidfilename);
252
253         if(pid) {
254                 if(netname)
255                         fprintf(stderr, _("A tincd is already running for net `%s' with pid %ld.\n"),
256                                         netname, (long)pid);
257                 else
258                         fprintf(stderr, _("A tincd is already running with pid %ld.\n"), (long)pid);
259                 return false;
260         }
261
262         /* if it's locked, write-protected, or whatever */
263         if(!write_pid(pidfilename)) {
264                 fprintf(stderr, _("Could write pid file %s: %s\n"), pidfilename, strerror(errno));
265                 return false;
266         }
267
268         return true;
269 }
270 #endif
271
272 /*
273   kill older tincd for this net
274 */
275 bool kill_other(int signal)
276 {
277 #ifndef HAVE_MINGW
278         pid_t pid;
279
280         cp();
281
282         pid = read_pid(pidfilename);
283
284         if(!pid) {
285                 if(netname)
286                         fprintf(stderr, _("No other tincd is running for net `%s'.\n"),
287                                         netname);
288                 else
289                         fprintf(stderr, _("No other tincd is running.\n"));
290                 return false;
291         }
292
293         errno = 0;                                      /* No error, sometimes errno is only changed on error */
294
295         /* ESRCH is returned when no process with that pid is found */
296         if(kill(pid, signal) && errno == ESRCH) {
297                 if(netname)
298                         fprintf(stderr, _("The tincd for net `%s' is no longer running. "),
299                                         netname);
300                 else
301                         fprintf(stderr, _("The tincd is no longer running. "));
302
303                 fprintf(stderr, _("Removing stale lock file.\n"));
304                 remove_pid(pidfilename);
305         }
306
307         return true;
308 #else
309         return remove_service();
310 #endif
311 }
312
313 /*
314   Detach from current terminal, write pidfile, kill parent
315 */
316 bool detach(void)
317 {
318         cp();
319
320         setup_signals();
321
322         /* First check if we can open a fresh new pidfile */
323
324 #ifndef HAVE_MINGW
325         if(!write_pidfile())
326                 return false;
327
328         /* If we succeeded in doing that, detach */
329
330         closelogger();
331 #endif
332
333         if(do_detach) {
334 #ifndef HAVE_MINGW
335                 if(daemon(0, 0)) {
336                         fprintf(stderr, _("Couldn't detach from terminal: %s"),
337                                         strerror(errno));
338                         return false;
339                 }
340
341                 /* Now UPDATE the pid in the pidfile, because we changed it... */
342
343                 if(!write_pid(pidfilename)) {
344                         fprintf(stderr, _("Could not write pid file %s: %s\n"), pidfilename, strerror(errno));
345                         return false;
346                 }
347 #else
348                 if(!statushandle)
349                         exit(install_service());
350 #endif
351         }
352
353         openlogger(identname, use_logfile?LOGMODE_FILE:(do_detach?LOGMODE_SYSLOG:LOGMODE_STDERR));
354
355         logger(LOG_NOTICE, _("tincd %s (%s %s) starting, debug level %d"),
356                            VERSION, __DATE__, __TIME__, debug_level);
357
358         xalloc_fail_func = memory_full;
359
360         return true;
361 }
362
363 bool execute_script(const char *name, char **envp)
364 {
365 #ifdef HAVE_SYSTEM
366         int status, len;
367         struct stat s;
368         char *scriptname, *p;
369         int i;
370
371         cp();
372
373 #ifndef HAVE_MINGW
374         len = asprintf(&scriptname, "\"%s/%s\"", confbase, name);
375 #else
376         len = asprintf(&scriptname, "\"%s/%s.bat\"", confbase, name);
377 #endif
378         if(len < 0)
379                 return false;
380
381         scriptname[len - 1] = '\0';
382
383         /* First check if there is a script */
384
385         if(stat(scriptname + 1, &s)) {
386                 free(scriptname);
387                 return true;
388         }
389
390         ifdebug(STATUS) logger(LOG_INFO, _("Executing script %s"), name);
391
392 #ifdef HAVE_PUTENV
393         /* Set environment */
394         
395         for(i = 0; envp[i]; i++)
396                 putenv(envp[i]);
397 #endif
398
399         scriptname[len - 1] = '\"';
400         status = system(scriptname);
401
402         free(scriptname);
403
404         /* Unset environment */
405
406         for(i = 0; envp[i]; i++) {
407                 char *e = strchr(envp[i], '=');
408                 if(e) {
409                         p = alloca(e - envp[i] + 1);
410                         strncpy(p, envp[i], e - envp[i]);
411                         p[e - envp[i]] = '\0';
412                         putenv(p);
413                 }
414         }
415
416 #ifdef WEXITSTATUS
417         if(status != -1) {
418                 if(WIFEXITED(status)) { /* Child exited by itself */
419                         if(WEXITSTATUS(status)) {
420                                 logger(LOG_ERR, _("Script %s exited with non-zero status %d"),
421                                            name, WEXITSTATUS(status));
422                                 return false;
423                         }
424                 } else if(WIFSIGNALED(status)) {        /* Child was killed by a signal */
425                         logger(LOG_ERR, _("Script %s was killed by signal %d (%s)"),
426                                    name, WTERMSIG(status), strsignal(WTERMSIG(status)));
427                         return false;
428                 } else {                        /* Something strange happened */
429                         logger(LOG_ERR, _("Script %s terminated abnormally"), name);
430                         return false;
431                 }
432         } else {
433                 logger(LOG_ERR, _("System call `%s' failed: %s"), "system", strerror(errno));
434                 return false;
435         }
436 #endif
437 #endif
438         return true;
439 }
440
441
442 /*
443   Signal handlers.
444 */
445
446 #ifndef HAVE_MINGW
447 static RETSIGTYPE sigterm_handler(int a)
448 {
449         logger(LOG_NOTICE, _("Got %s signal"), "TERM");
450         if(running)
451                 running = false;
452         else
453                 exit(1);
454 }
455
456 static RETSIGTYPE sigquit_handler(int a)
457 {
458         logger(LOG_NOTICE, _("Got %s signal"), "QUIT");
459         if(running)
460                 running = false;
461         else
462                 exit(1);
463 }
464
465 static RETSIGTYPE fatal_signal_square(int a)
466 {
467         logger(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a,
468                    strsignal(a));
469         cp_trace();
470         exit(1);
471 }
472
473 static RETSIGTYPE fatal_signal_handler(int a)
474 {
475         struct sigaction act;
476         logger(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
477         cp_trace();
478
479         if(do_detach) {
480                 logger(LOG_NOTICE, _("Trying to re-execute in 5 seconds..."));
481
482                 act.sa_handler = fatal_signal_square;
483                 act.sa_mask = emptysigset;
484                 act.sa_flags = 0;
485                 sigaction(SIGSEGV, &act, NULL);
486
487                 close_network_connections();
488                 sleep(5);
489                 remove_pid(pidfilename);
490                 execvp(g_argv[0], g_argv);
491         } else {
492                 logger(LOG_NOTICE, _("Not restarting."));
493                 exit(1);
494         }
495 }
496
497 static RETSIGTYPE sighup_handler(int a)
498 {
499         logger(LOG_NOTICE, _("Got %s signal"), "HUP");
500         sighup = true;
501 }
502
503 static RETSIGTYPE sigint_handler(int a)
504 {
505         logger(LOG_NOTICE, _("Got %s signal"), "INT");
506
507         if(saved_debug_level != -1) {
508                 logger(LOG_NOTICE, _("Reverting to old debug level (%d)"),
509                         saved_debug_level);
510                 debug_level = saved_debug_level;
511                 saved_debug_level = -1;
512         } else {
513                 logger(LOG_NOTICE,
514                         _("Temporarily setting debug level to 5.  Kill me with SIGINT again to go back to level %d."),
515                         debug_level);
516                 saved_debug_level = debug_level;
517                 debug_level = 5;
518         }
519 }
520
521 static RETSIGTYPE sigalrm_handler(int a)
522 {
523         logger(LOG_NOTICE, _("Got %s signal"), "ALRM");
524         sigalrm = true;
525 }
526
527 static RETSIGTYPE sigusr1_handler(int a)
528 {
529         dump_connections();
530 }
531
532 static RETSIGTYPE sigusr2_handler(int a)
533 {
534         dump_device_stats();
535         dump_nodes();
536         dump_edges();
537         dump_subnets();
538 }
539
540 static RETSIGTYPE sigwinch_handler(int a)
541 {
542         do_purge = true;
543 }
544
545 static RETSIGTYPE unexpected_signal_handler(int a)
546 {
547         logger(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
548         cp_trace();
549 }
550
551 static RETSIGTYPE ignore_signal_handler(int a)
552 {
553         ifdebug(SCARY_THINGS) logger(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
554 }
555
556 static struct {
557         int signal;
558         void (*handler)(int);
559 } sighandlers[] = {
560         {SIGHUP, sighup_handler},
561         {SIGTERM, sigterm_handler},
562         {SIGQUIT, sigquit_handler},
563         {SIGSEGV, fatal_signal_handler},
564         {SIGBUS, fatal_signal_handler},
565         {SIGILL, fatal_signal_handler},
566         {SIGPIPE, ignore_signal_handler},
567         {SIGINT, sigint_handler},
568         {SIGUSR1, sigusr1_handler},
569         {SIGUSR2, sigusr2_handler},
570         {SIGCHLD, ignore_signal_handler},
571         {SIGALRM, sigalrm_handler},
572         {SIGWINCH, sigwinch_handler},
573         {0, NULL}
574 };
575 #endif
576
577 void setup_signals(void)
578 {
579 #ifndef HAVE_MINGW
580         int i;
581         struct sigaction act;
582
583         sigemptyset(&emptysigset);
584         act.sa_handler = NULL;
585         act.sa_mask = emptysigset;
586         act.sa_flags = 0;
587
588         /* Set a default signal handler for every signal, errors will be
589            ignored. */
590         for(i = 0; i < NSIG; i++) {
591                 if(!do_detach)
592                         act.sa_handler = SIG_DFL;
593                 else
594                         act.sa_handler = unexpected_signal_handler;
595                 sigaction(i, &act, NULL);
596         }
597
598         /* If we didn't detach, allow coredumps */
599         if(!do_detach)
600                 sighandlers[3].handler = SIG_DFL;
601
602         /* Then, for each known signal that we want to catch, assign a
603            handler to the signal, with error checking this time. */
604         for(i = 0; sighandlers[i].signal; i++) {
605                 act.sa_handler = sighandlers[i].handler;
606                 if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
607                         fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
608                                         sighandlers[i].signal, strsignal(sighandlers[i].signal),
609                                         strerror(errno));
610         }
611 #endif
612 }