xref: /freebsd/usr.sbin/nscd/nscd.c (revision 814aaaa7da4dab462d90e12e7b48b75f2093ccfd)
1 /*-
2  * Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in thereg
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/event.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/time.h>
36 #include <sys/un.h>
37 
38 #include <assert.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <fcntl.h>
42 #include <libutil.h>
43 #include <pthread.h>
44 #include <signal.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "agents/passwd.h"
51 #include "agents/group.h"
52 #include "agents/services.h"
53 #include "cachelib.h"
54 #include "config.h"
55 #include "debug.h"
56 #include "log.h"
57 #include "nscdcli.h"
58 #include "parser.h"
59 #include "query.h"
60 #include "singletons.h"
61 
62 #ifndef CONFIG_PATH
63 #define CONFIG_PATH "/etc/nscd.conf"
64 #endif
65 #define DEFAULT_CONFIG_PATH	"nscd.conf"
66 
67 #define MAX_SOCKET_IO_SIZE	4096
68 
69 struct processing_thread_args {
70 	cache	the_cache;
71 	struct configuration	*the_configuration;
72 	struct runtime_env		*the_runtime_env;
73 };
74 
75 static void accept_connection(struct kevent *, struct runtime_env *,
76 	struct configuration *);
77 static void destroy_cache_(cache);
78 static void destroy_runtime_env(struct runtime_env *);
79 static cache init_cache_(struct configuration *);
80 static struct runtime_env *init_runtime_env(struct configuration *);
81 static void processing_loop(cache, struct runtime_env *,
82 	struct configuration *);
83 static void process_socket_event(struct kevent *, struct runtime_env *,
84 	struct configuration *);
85 static void process_timer_event(struct kevent *, struct runtime_env *,
86 	struct configuration *);
87 static void *processing_thread(void *);
88 static void usage(void);
89 
90 void get_time_func(struct timeval *);
91 
92 static void
93 usage(void)
94 {
95 	fprintf(stderr,
96 	    "usage: nscd [-dnst] [-i cachename] [-I cachename]\n");
97 	exit(1);
98 }
99 
100 static cache
101 init_cache_(struct configuration *config)
102 {
103 	struct cache_params params;
104 	cache retval;
105 
106 	struct configuration_entry *config_entry;
107 	size_t	size, i;
108 	int res;
109 
110 	TRACE_IN(init_cache_);
111 
112 	memset(&params, 0, sizeof(struct cache_params));
113 	params.get_time_func = get_time_func;
114 	retval = init_cache(&params);
115 
116 	size = configuration_get_entries_size(config);
117 	for (i = 0; i < size; ++i) {
118 		config_entry = configuration_get_entry(config, i);
119 	    	/*
120 	    	 * We should register common entries now - multipart entries
121 	    	 * would be registered automatically during the queries.
122 	    	 */
123 		res = register_cache_entry(retval, (struct cache_entry_params *)
124 			&config_entry->positive_cache_params);
125 		config_entry->positive_cache_entry = find_cache_entry(retval,
126 			config_entry->positive_cache_params.cep.entry_name);
127 		assert(config_entry->positive_cache_entry !=
128 			INVALID_CACHE_ENTRY);
129 
130 		res = register_cache_entry(retval, (struct cache_entry_params *)
131 			&config_entry->negative_cache_params);
132 		config_entry->negative_cache_entry = find_cache_entry(retval,
133 			config_entry->negative_cache_params.cep.entry_name);
134 		assert(config_entry->negative_cache_entry !=
135 			INVALID_CACHE_ENTRY);
136 	}
137 
138 	LOG_MSG_2("cache", "cache was successfully initialized");
139 	TRACE_OUT(init_cache_);
140 	return (retval);
141 }
142 
143 static void
144 destroy_cache_(cache the_cache)
145 {
146 	TRACE_IN(destroy_cache_);
147 	destroy_cache(the_cache);
148 	TRACE_OUT(destroy_cache_);
149 }
150 
151 /*
152  * Socket and kqueues are prepared here. We have one global queue for both
153  * socket and timers events.
154  */
155 static struct runtime_env *
156 init_runtime_env(struct configuration *config)
157 {
158 	int serv_addr_len;
159 	struct sockaddr_un serv_addr;
160 
161 	struct kevent eventlist;
162 	struct timespec timeout;
163 
164 	struct runtime_env *retval;
165 
166 	TRACE_IN(init_runtime_env);
167 	retval = calloc(1, sizeof(*retval));
168 	assert(retval != NULL);
169 
170 	retval->sockfd = socket(PF_LOCAL, SOCK_STREAM|SOCK_NONBLOCK, 0);
171 
172 	if (config->force_unlink == 1)
173 		unlink(config->socket_path);
174 
175 	memset(&serv_addr, 0, sizeof(struct sockaddr_un));
176 	serv_addr.sun_family = PF_LOCAL;
177 	strlcpy(serv_addr.sun_path, config->socket_path,
178 		sizeof(serv_addr.sun_path));
179 	serv_addr_len = sizeof(serv_addr.sun_family) +
180 		strlen(serv_addr.sun_path) + 1;
181 
182 	if (bind(retval->sockfd, (struct sockaddr *)&serv_addr,
183 		serv_addr_len) == -1) {
184 		close(retval->sockfd);
185 		free(retval);
186 
187 		LOG_ERR_2("runtime environment", "can't bind socket to path: "
188 			"%s", config->socket_path);
189 		TRACE_OUT(init_runtime_env);
190 		return (NULL);
191 	}
192 	LOG_MSG_2("runtime environment", "using socket %s",
193 		config->socket_path);
194 
195 	/*
196 	 * Here we're marking socket as non-blocking and setting its backlog
197 	 * to the maximum value
198 	 */
199 	chmod(config->socket_path, config->socket_mode);
200 	listen(retval->sockfd, -1);
201 
202 	retval->queue = kqueue();
203 	assert(retval->queue != -1);
204 
205 	EV_SET(&eventlist, retval->sockfd, EVFILT_READ, EV_ADD | EV_ONESHOT,
206 		0, 0, 0);
207 	memset(&timeout, 0, sizeof(struct timespec));
208 	kevent(retval->queue, &eventlist, 1, NULL, 0, &timeout);
209 
210 	LOG_MSG_2("runtime environment", "successfully initialized");
211 	TRACE_OUT(init_runtime_env);
212 	return (retval);
213 }
214 
215 static void
216 destroy_runtime_env(struct runtime_env *env)
217 {
218 	TRACE_IN(destroy_runtime_env);
219 	close(env->queue);
220 	close(env->sockfd);
221 	free(env);
222 	TRACE_OUT(destroy_runtime_env);
223 }
224 
225 static void
226 accept_connection(struct kevent *event_data, struct runtime_env *env,
227 	struct configuration *config)
228 {
229 	struct kevent	eventlist[2];
230 	struct timespec	timeout;
231 	struct query_state	*qstate;
232 
233 	int	fd;
234 	int	res;
235 
236 	uid_t	euid;
237 	gid_t	egid;
238 
239 	TRACE_IN(accept_connection);
240 	fd = accept(event_data->ident, NULL, NULL);
241 	if (fd == -1) {
242 		LOG_ERR_2("accept_connection", "error %d during accept()",
243 		    errno);
244 		TRACE_OUT(accept_connection);
245 		return;
246 	}
247 
248 	if (getpeereid(fd, &euid, &egid) != 0) {
249 		LOG_ERR_2("accept_connection", "error %d during getpeereid()",
250 			errno);
251 		TRACE_OUT(accept_connection);
252 		return;
253 	}
254 
255 	qstate = init_query_state(fd, sizeof(int), euid, egid);
256 	if (qstate == NULL) {
257 		LOG_ERR_2("accept_connection", "can't init query_state");
258 		TRACE_OUT(accept_connection);
259 		return;
260 	}
261 
262 	memset(&timeout, 0, sizeof(struct timespec));
263 	EV_SET(&eventlist[0], fd, EVFILT_TIMER, EV_ADD | EV_ONESHOT,
264 		0, qstate->timeout.tv_sec * 1000, qstate);
265 	EV_SET(&eventlist[1], fd, EVFILT_READ, EV_ADD | EV_ONESHOT,
266 		NOTE_LOWAT, qstate->kevent_watermark, qstate);
267 	res = kevent(env->queue, eventlist, 2, NULL, 0, &timeout);
268 	if (res < 0)
269 		LOG_ERR_2("accept_connection", "kevent error");
270 
271 	TRACE_OUT(accept_connection);
272 }
273 
274 static void
275 process_socket_event(struct kevent *event_data, struct runtime_env *env,
276 	struct configuration *config)
277 {
278 	struct kevent	eventlist[2];
279 	struct timeval	query_timeout;
280 	struct timespec	kevent_timeout;
281 	int	nevents;
282 	int	eof_res, res;
283 	ssize_t	io_res;
284 	struct query_state *qstate;
285 
286 	TRACE_IN(process_socket_event);
287 	eof_res = event_data->flags & EV_EOF ? 1 : 0;
288 	res = 0;
289 
290 	memset(&kevent_timeout, 0, sizeof(struct timespec));
291 	EV_SET(&eventlist[0], event_data->ident, EVFILT_TIMER, EV_DELETE,
292 		0, 0, NULL);
293 	nevents = kevent(env->queue, eventlist, 1, NULL, 0, &kevent_timeout);
294 	if (nevents == -1) {
295 		if (errno == ENOENT) {
296 			/* the timer is already handling this event */
297 			TRACE_OUT(process_socket_event);
298 			return;
299 		} else {
300 			/* some other error happened */
301 			LOG_ERR_2("process_socket_event", "kevent error, errno"
302 				" is %d", errno);
303 			TRACE_OUT(process_socket_event);
304 			return;
305 		}
306 	}
307 	qstate = (struct query_state *)event_data->udata;
308 
309 	/*
310 	 * If the buffer that is to be send/received is too large,
311 	 * we send it implicitly, by using query_io_buffer_read and
312 	 * query_io_buffer_write functions in the query_state. These functions
313 	 * use the temporary buffer, which is later send/received in parts.
314 	 * The code below implements buffer splitting/mergind for send/receive
315 	 * operations. It also does the actual socket IO operations.
316 	 */
317 	if (((qstate->use_alternate_io == 0) &&
318 		(qstate->kevent_watermark <= (size_t)event_data->data)) ||
319 		((qstate->use_alternate_io != 0) &&
320 		(qstate->io_buffer_watermark <= (size_t)event_data->data))) {
321 		if (qstate->use_alternate_io != 0) {
322 			switch (qstate->io_buffer_filter) {
323 			case EVFILT_READ:
324 				io_res = query_socket_read(qstate,
325 					qstate->io_buffer_p,
326 					qstate->io_buffer_watermark);
327 				if (io_res < 0) {
328 					qstate->use_alternate_io = 0;
329 					qstate->process_func = NULL;
330 				} else {
331 					qstate->io_buffer_p += io_res;
332 					if (qstate->io_buffer_p ==
333 					    	qstate->io_buffer +
334 						qstate->io_buffer_size) {
335 						qstate->io_buffer_p =
336 						    qstate->io_buffer;
337 						qstate->use_alternate_io = 0;
338 					}
339 				}
340 			break;
341 			default:
342 			break;
343 			}
344 		}
345 
346 		if (qstate->use_alternate_io == 0) {
347 			do {
348 				res = qstate->process_func(qstate);
349 			} while ((qstate->kevent_watermark == 0) &&
350 					(qstate->process_func != NULL) &&
351 					(res == 0));
352 
353 			if (res != 0)
354 				qstate->process_func = NULL;
355 		}
356 
357 		if ((qstate->use_alternate_io != 0) &&
358 			(qstate->io_buffer_filter == EVFILT_WRITE)) {
359 			io_res = query_socket_write(qstate, qstate->io_buffer_p,
360 				qstate->io_buffer_watermark);
361 			if (io_res < 0) {
362 				qstate->use_alternate_io = 0;
363 				qstate->process_func = NULL;
364 			} else
365 				qstate->io_buffer_p += io_res;
366 		}
367 	} else {
368 		/* assuming that socket was closed */
369 		qstate->process_func = NULL;
370 		qstate->use_alternate_io = 0;
371 	}
372 
373 	if (((qstate->process_func == NULL) &&
374 	    	(qstate->use_alternate_io == 0)) ||
375 		(eof_res != 0) || (res != 0)) {
376 		destroy_query_state(qstate);
377 		close(event_data->ident);
378 		TRACE_OUT(process_socket_event);
379 		return;
380 	}
381 
382 	/* updating the query_state lifetime variable */
383 	get_time_func(&query_timeout);
384 	query_timeout.tv_usec = 0;
385 	query_timeout.tv_sec -= qstate->creation_time.tv_sec;
386 	if (query_timeout.tv_sec > qstate->timeout.tv_sec)
387 		query_timeout.tv_sec = 0;
388 	else
389 		query_timeout.tv_sec = qstate->timeout.tv_sec -
390 			query_timeout.tv_sec;
391 
392 	if ((qstate->use_alternate_io != 0) && (qstate->io_buffer_p ==
393 		qstate->io_buffer + qstate->io_buffer_size))
394 		qstate->use_alternate_io = 0;
395 
396 	if (qstate->use_alternate_io == 0) {
397 		/*
398 		 * If we must send/receive the large block of data,
399 		 * we should prepare the query_state's io_XXX fields.
400 		 * We should also substitute its write_func and read_func
401 		 * with the query_io_buffer_write and query_io_buffer_read,
402 		 * which will allow us to implicitly send/receive this large
403 		 * buffer later (in the subsequent calls to the
404 		 * process_socket_event).
405 		 */
406 		if (qstate->kevent_watermark > MAX_SOCKET_IO_SIZE) {
407 			if (qstate->io_buffer != NULL)
408 				free(qstate->io_buffer);
409 
410 			qstate->io_buffer = calloc(1,
411 				qstate->kevent_watermark);
412 			assert(qstate->io_buffer != NULL);
413 
414 			qstate->io_buffer_p = qstate->io_buffer;
415 			qstate->io_buffer_size = qstate->kevent_watermark;
416 			qstate->io_buffer_filter = qstate->kevent_filter;
417 
418 			qstate->write_func = query_io_buffer_write;
419 			qstate->read_func = query_io_buffer_read;
420 
421 			if (qstate->kevent_filter == EVFILT_READ)
422 				qstate->use_alternate_io = 1;
423 
424 			qstate->io_buffer_watermark = MAX_SOCKET_IO_SIZE;
425 			EV_SET(&eventlist[1], event_data->ident,
426 				qstate->kevent_filter, EV_ADD | EV_ONESHOT,
427 				NOTE_LOWAT, MAX_SOCKET_IO_SIZE, qstate);
428 		} else {
429 			EV_SET(&eventlist[1], event_data->ident,
430 		    		qstate->kevent_filter, EV_ADD | EV_ONESHOT,
431 		    		NOTE_LOWAT, qstate->kevent_watermark, qstate);
432 		}
433 	} else {
434 		if (qstate->io_buffer + qstate->io_buffer_size -
435 		    	qstate->io_buffer_p <
436 			MAX_SOCKET_IO_SIZE) {
437 			qstate->io_buffer_watermark = qstate->io_buffer +
438 				qstate->io_buffer_size - qstate->io_buffer_p;
439 			EV_SET(&eventlist[1], event_data->ident,
440 			    	qstate->io_buffer_filter,
441 				EV_ADD | EV_ONESHOT, NOTE_LOWAT,
442 				qstate->io_buffer_watermark,
443 				qstate);
444 		} else {
445 			qstate->io_buffer_watermark = MAX_SOCKET_IO_SIZE;
446 			EV_SET(&eventlist[1], event_data->ident,
447 		    		qstate->io_buffer_filter, EV_ADD | EV_ONESHOT,
448 		    		NOTE_LOWAT, MAX_SOCKET_IO_SIZE, qstate);
449 		}
450 	}
451 	EV_SET(&eventlist[0], event_data->ident, EVFILT_TIMER,
452 		EV_ADD | EV_ONESHOT, 0, query_timeout.tv_sec * 1000, qstate);
453 	kevent(env->queue, eventlist, 2, NULL, 0, &kevent_timeout);
454 
455 	TRACE_OUT(process_socket_event);
456 }
457 
458 /*
459  * This routine is called if timer event has been signaled in the kqueue. It
460  * just closes the socket and destroys the query_state.
461  */
462 static void
463 process_timer_event(struct kevent *event_data, struct runtime_env *env,
464 	struct configuration *config)
465 {
466 	struct query_state	*qstate;
467 
468 	TRACE_IN(process_timer_event);
469 	qstate = (struct query_state *)event_data->udata;
470 	destroy_query_state(qstate);
471 	close(event_data->ident);
472 	TRACE_OUT(process_timer_event);
473 }
474 
475 /*
476  * Processing loop is the basic processing routine, that forms a body of each
477  * procssing thread
478  */
479 static void
480 processing_loop(cache the_cache, struct runtime_env *env,
481 	struct configuration *config)
482 {
483 	struct timespec timeout;
484 	const int eventlist_size = 1;
485 	struct kevent eventlist[eventlist_size];
486 	int nevents, i;
487 
488 	TRACE_MSG("=> processing_loop");
489 	memset(&timeout, 0, sizeof(struct timespec));
490 	memset(&eventlist, 0, sizeof(struct kevent) * eventlist_size);
491 
492 	for (;;) {
493 		nevents = kevent(env->queue, NULL, 0, eventlist,
494 	    		eventlist_size, NULL);
495 		/*
496 		 * we can only receive 1 event on success
497 		 */
498 		if (nevents == 1) {
499 			struct kevent *event_data;
500 			event_data = &eventlist[0];
501 
502 			if ((int)event_data->ident == env->sockfd) {
503 				for (i = 0; i < event_data->data; ++i)
504 				    accept_connection(event_data, env, config);
505 
506 				EV_SET(eventlist, s_runtime_env->sockfd,
507 				    EVFILT_READ, EV_ADD | EV_ONESHOT,
508 				    0, 0, 0);
509 				memset(&timeout, 0,
510 				    sizeof(struct timespec));
511 				kevent(s_runtime_env->queue, eventlist,
512 				    1, NULL, 0, &timeout);
513 
514 			} else {
515 				switch (event_data->filter) {
516 				case EVFILT_READ:
517 				case EVFILT_WRITE:
518 					process_socket_event(event_data,
519 						env, config);
520 					break;
521 				case EVFILT_TIMER:
522 					process_timer_event(event_data,
523 						env, config);
524 					break;
525 				default:
526 					break;
527 				}
528 			}
529 		} else {
530 			/* this branch shouldn't be currently executed */
531 		}
532 	}
533 
534 	TRACE_MSG("<= processing_loop");
535 }
536 
537 /*
538  * Wrapper above the processing loop function. It sets the thread signal mask
539  * to avoid SIGPIPE signals (which can happen if the client works incorrectly).
540  */
541 static void *
542 processing_thread(void *data)
543 {
544 	struct processing_thread_args	*args;
545 	sigset_t new;
546 
547 	TRACE_MSG("=> processing_thread");
548 	args = (struct processing_thread_args *)data;
549 
550 	sigemptyset(&new);
551 	sigaddset(&new, SIGPIPE);
552 	if (pthread_sigmask(SIG_BLOCK, &new, NULL) != 0)
553 		LOG_ERR_1("processing thread",
554 			"thread can't block the SIGPIPE signal");
555 
556 	processing_loop(args->the_cache, args->the_runtime_env,
557 		args->the_configuration);
558 	free(args);
559 	TRACE_MSG("<= processing_thread");
560 
561 	return (NULL);
562 }
563 
564 void
565 get_time_func(struct timeval *time)
566 {
567 	struct timespec res;
568 	memset(&res, 0, sizeof(struct timespec));
569 	clock_gettime(CLOCK_MONOTONIC, &res);
570 
571 	time->tv_sec = res.tv_sec;
572 	time->tv_usec = 0;
573 }
574 
575 /*
576  * The idea of _nss_cache_cycle_prevention_function is that nsdispatch
577  * will search for this symbol in the executable. This symbol is the
578  * attribute of the caching daemon. So, if it exists, nsdispatch won't try
579  * to connect to the caching daemon and will just ignore the 'cache'
580  * source in the nsswitch.conf. This method helps to avoid cycles and
581  * organize self-performing requests.
582  *
583  * (not actually a function; it used to be, but it doesn't make any
584  * difference, as long as it has external linkage)
585  */
586 void *_nss_cache_cycle_prevention_function;
587 
588 int
589 main(int argc, char *argv[])
590 {
591 	struct processing_thread_args *thread_args;
592 	pthread_t *threads;
593 
594 	struct pidfh *pidfile;
595 	pid_t pid;
596 
597 	char const *config_file;
598 	char const *error_str;
599 	int error_line;
600 	int i, res;
601 
602 	int trace_mode_enabled;
603 	int force_single_threaded;
604 	int do_not_daemonize;
605 	int clear_user_cache_entries, clear_all_cache_entries;
606 	char *user_config_entry_name, *global_config_entry_name;
607 	int show_statistics;
608 	int daemon_mode, interactive_mode;
609 
610 
611 	/* by default all debug messages are omitted */
612 	TRACE_OFF();
613 
614 	/* parsing command line arguments */
615 	trace_mode_enabled = 0;
616 	force_single_threaded = 0;
617 	do_not_daemonize = 0;
618 	clear_user_cache_entries = 0;
619 	clear_all_cache_entries = 0;
620 	show_statistics = 0;
621 	user_config_entry_name = NULL;
622 	global_config_entry_name = NULL;
623 	while ((res = getopt(argc, argv, "nstdi:I:")) != -1) {
624 		switch (res) {
625 		case 'n':
626 			do_not_daemonize = 1;
627 			break;
628 		case 's':
629 			force_single_threaded = 1;
630 			break;
631 		case 't':
632 			trace_mode_enabled = 1;
633 			break;
634 		case 'i':
635 			clear_user_cache_entries = 1;
636 			if (optarg != NULL)
637 				if (strcmp(optarg, "all") != 0)
638 					user_config_entry_name = strdup(optarg);
639 			break;
640 		case 'I':
641 			clear_all_cache_entries = 1;
642 			if (optarg != NULL)
643 				if (strcmp(optarg, "all") != 0)
644 					global_config_entry_name =
645 						strdup(optarg);
646 			break;
647 		case 'd':
648 			show_statistics = 1;
649 			break;
650 		case '?':
651 		default:
652 			usage();
653 			/* NOT REACHED */
654 		}
655 	}
656 
657 	daemon_mode = do_not_daemonize | force_single_threaded |
658 		trace_mode_enabled;
659 	interactive_mode = clear_user_cache_entries | clear_all_cache_entries |
660 		show_statistics;
661 
662 	if ((daemon_mode != 0) && (interactive_mode != 0)) {
663 		LOG_ERR_1("main", "daemon mode and interactive_mode arguments "
664 			"can't be used together");
665 		usage();
666 	}
667 
668 	if (interactive_mode != 0) {
669 		FILE *pidfin = fopen(DEFAULT_PIDFILE_PATH, "r");
670 		char pidbuf[256];
671 
672 		struct nscd_connection_params connection_params;
673 		nscd_connection connection;
674 
675 		int result;
676 
677 		if (pidfin == NULL)
678 			errx(EXIT_FAILURE, "There is no daemon running.");
679 
680 		memset(pidbuf, 0, sizeof(pidbuf));
681 		fread(pidbuf, sizeof(pidbuf) - 1, 1, pidfin);
682 		fclose(pidfin);
683 
684 		if (ferror(pidfin) != 0)
685 			errx(EXIT_FAILURE, "Can't read from pidfile.");
686 
687 		if (sscanf(pidbuf, "%d", &pid) != 1)
688 			errx(EXIT_FAILURE, "Invalid pidfile.");
689 		LOG_MSG_1("main", "daemon PID is %d", pid);
690 
691 
692 		memset(&connection_params, 0,
693 			sizeof(struct nscd_connection_params));
694 		connection_params.socket_path = DEFAULT_SOCKET_PATH;
695 		connection = open_nscd_connection__(&connection_params);
696 		if (connection == INVALID_NSCD_CONNECTION)
697 			errx(EXIT_FAILURE, "Can't connect to the daemon.");
698 
699 		if (clear_user_cache_entries != 0) {
700 			result = nscd_transform__(connection,
701 				user_config_entry_name, TT_USER);
702 			if (result != 0)
703 				LOG_MSG_1("main",
704 					"user cache transformation failed");
705 			else
706 				LOG_MSG_1("main",
707 					"user cache_transformation "
708 					"succeeded");
709 		}
710 
711 		if (clear_all_cache_entries != 0) {
712 			if (geteuid() != 0)
713 				errx(EXIT_FAILURE, "Only root can initiate "
714 					"global cache transformation.");
715 
716 			result = nscd_transform__(connection,
717 				global_config_entry_name, TT_ALL);
718 			if (result != 0)
719 				LOG_MSG_1("main",
720 					"global cache transformation "
721 					"failed");
722 			else
723 				LOG_MSG_1("main",
724 					"global cache transformation "
725 					"succeeded");
726 		}
727 
728 		close_nscd_connection__(connection);
729 
730 		free(user_config_entry_name);
731 		free(global_config_entry_name);
732 		return (EXIT_SUCCESS);
733 	}
734 
735 	pidfile = pidfile_open(DEFAULT_PIDFILE_PATH, 0644, &pid);
736 	if (pidfile == NULL) {
737 		if (errno == EEXIST)
738 			errx(EXIT_FAILURE, "Daemon already running, pid: %d.",
739 				pid);
740 		warn("Cannot open or create pidfile");
741 	}
742 
743 	if (trace_mode_enabled == 1)
744 		TRACE_ON();
745 
746 	/* blocking the main thread from receiving SIGPIPE signal */
747 	sigblock(sigmask(SIGPIPE));
748 
749 	/* daemonization */
750 	if (do_not_daemonize == 0) {
751 		res = daemon(0, trace_mode_enabled == 0 ? 0 : 1);
752 		if (res != 0) {
753 			LOG_ERR_1("main", "can't daemonize myself: %s",
754 		    		strerror(errno));
755 			pidfile_remove(pidfile);
756 			goto fin;
757 		} else
758 			LOG_MSG_1("main", "successfully daemonized");
759 	}
760 
761 	pidfile_write(pidfile);
762 
763 	s_agent_table = init_agent_table();
764 	register_agent(s_agent_table, init_passwd_agent());
765 	register_agent(s_agent_table, init_passwd_mp_agent());
766 	register_agent(s_agent_table, init_group_agent());
767 	register_agent(s_agent_table, init_group_mp_agent());
768 	register_agent(s_agent_table, init_services_agent());
769 	register_agent(s_agent_table, init_services_mp_agent());
770 	LOG_MSG_1("main", "request agents registered successfully");
771 
772 	/*
773  	 * Hosts agent can't work properly until we have access to the
774 	 * appropriate dtab structures, which are used in nsdispatch
775 	 * calls
776 	 *
777 	 register_agent(s_agent_table, init_hosts_agent());
778 	*/
779 
780 	/* configuration initialization */
781 	s_configuration = init_configuration();
782 	fill_configuration_defaults(s_configuration);
783 
784 	error_str = NULL;
785 	error_line = 0;
786 	config_file = CONFIG_PATH;
787 
788 	res = parse_config_file(s_configuration, config_file, &error_str,
789 		&error_line);
790 	if ((res != 0) && (error_str == NULL)) {
791 		config_file = DEFAULT_CONFIG_PATH;
792 		res = parse_config_file(s_configuration, config_file,
793 			&error_str, &error_line);
794 	}
795 
796 	if (res != 0) {
797 		if (error_str != NULL) {
798 		LOG_ERR_1("main", "error in configuration file(%s, %d): %s\n",
799 			config_file, error_line, error_str);
800 		} else {
801 		LOG_ERR_1("main", "no configuration file found "
802 		    	"- was looking for %s and %s",
803 			CONFIG_PATH, DEFAULT_CONFIG_PATH);
804 		}
805 		destroy_configuration(s_configuration);
806 		return (-1);
807 	}
808 
809 	if (force_single_threaded == 1)
810 		s_configuration->threads_num = 1;
811 
812 	/* cache initialization */
813 	s_cache = init_cache_(s_configuration);
814 	if (s_cache == NULL) {
815 		LOG_ERR_1("main", "can't initialize the cache");
816 		destroy_configuration(s_configuration);
817 		return (-1);
818 	}
819 
820 	/* runtime environment initialization */
821 	s_runtime_env = init_runtime_env(s_configuration);
822 	if (s_runtime_env == NULL) {
823 		LOG_ERR_1("main", "can't initialize the runtime environment");
824 		destroy_configuration(s_configuration);
825 		destroy_cache_(s_cache);
826 		return (-1);
827 	}
828 
829 	if (s_configuration->threads_num > 1) {
830 		threads = calloc(1, sizeof(*threads) *
831 			s_configuration->threads_num);
832 		for (i = 0; i < s_configuration->threads_num; ++i) {
833 			thread_args = malloc(
834 				sizeof(*thread_args));
835 			thread_args->the_cache = s_cache;
836 			thread_args->the_runtime_env = s_runtime_env;
837 			thread_args->the_configuration = s_configuration;
838 
839 			LOG_MSG_1("main", "thread #%d was successfully created",
840 				i);
841 			pthread_create(&threads[i], NULL, processing_thread,
842 				thread_args);
843 
844 			thread_args = NULL;
845 		}
846 
847 		for (i = 0; i < s_configuration->threads_num; ++i)
848 			pthread_join(threads[i], NULL);
849 	} else {
850 		LOG_MSG_1("main", "working in single-threaded mode");
851 		processing_loop(s_cache, s_runtime_env, s_configuration);
852 	}
853 
854 fin:
855 	/* runtime environment destruction */
856 	destroy_runtime_env(s_runtime_env);
857 
858 	/* cache destruction */
859 	destroy_cache_(s_cache);
860 
861 	/* configuration destruction */
862 	destroy_configuration(s_configuration);
863 
864 	/* agents table destruction */
865 	destroy_agent_table(s_agent_table);
866 
867 	pidfile_remove(pidfile);
868 	return (EXIT_SUCCESS);
869 }
870