xref: /titanic_52/usr/src/cmd/nscd/nscd_frontend.c (revision 18c2aff776a775d34a4c9893a4c72e0434d68e36)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <stdlib.h>
29 #include <alloca.h>
30 #include <signal.h>
31 #include <sys/stat.h>
32 #include <unistd.h>
33 #include <pthread.h>
34 #include <time.h>
35 #include <errno.h>
36 #include <door.h>
37 #include <zone.h>
38 #include <resolv.h>
39 #include <sys/socket.h>
40 #include <net/route.h>
41 #include <string.h>
42 #include <net/if.h>
43 #include <sys/stat.h>
44 #include <fcntl.h>
45 #include "nscd_common.h"
46 #include "nscd_door.h"
47 #include "nscd_config.h"
48 #include "nscd_switch.h"
49 #include "nscd_log.h"
50 #include "nscd_selfcred.h"
51 #include "nscd_frontend.h"
52 #include "nscd_admin.h"
53 
54 static void rts_mon(void);
55 static void keep_open_dns_socket(void);
56 
57 extern nsc_ctx_t *cache_ctx_p[];
58 
59 /*
60  * Current active Configuration data for the frontend component
61  */
62 static nscd_cfg_global_frontend_t	frontend_cfg_g;
63 static nscd_cfg_frontend_t		*frontend_cfg;
64 
65 static int	max_servers = 0;
66 static int	max_servers_set = 0;
67 static int	per_user_is_on = 1;
68 
69 static char	*main_execname;
70 static char	**main_argv;
71 extern int	_whoami;
72 extern long	activity;
73 extern mutex_t	activity_lock;
74 
75 static sema_t	common_sema;
76 
77 static thread_key_t	lookup_state_key;
78 static mutex_t		create_lock = DEFAULTMUTEX;
79 static int		num_servers = 0;
80 static thread_key_t	server_key;
81 
82 /*
83  * Bind a TSD value to a server thread. This enables the destructor to
84  * be called if/when this thread exits.  This would be a programming
85  * error, but better safe than sorry.
86  */
87 /*ARGSUSED*/
88 static void *
89 server_tsd_bind(void *arg)
90 {
91 	static void *value = 0;
92 
93 	/* disable cancellation to avoid hangs if server threads disappear */
94 	(void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
95 	(void) thr_setspecific(server_key, value);
96 	(void) door_return(NULL, 0, NULL, 0);
97 
98 	/* make lint happy */
99 	return (NULL);
100 }
101 
102 /*
103  * Server threads are created here.
104  */
105 /*ARGSUSED*/
106 static void
107 server_create(door_info_t *dip)
108 {
109 	(void) mutex_lock(&create_lock);
110 	if (++num_servers > max_servers) {
111 		num_servers--;
112 		(void) mutex_unlock(&create_lock);
113 		return;
114 	}
115 	(void) mutex_unlock(&create_lock);
116 	(void) thr_create(NULL, 0, server_tsd_bind, NULL,
117 			THR_BOUND|THR_DETACHED, NULL);
118 }
119 
120 /*
121  * Server thread are destroyed here
122  */
123 /*ARGSUSED*/
124 static void
125 server_destroy(void *arg)
126 {
127 	(void) mutex_lock(&create_lock);
128 	num_servers--;
129 	(void) mutex_unlock(&create_lock);
130 }
131 
132 /*
133  * get clearance
134  */
135 int
136 _nscd_get_clearance(sema_t *sema) {
137 	if (sema_trywait(&common_sema) == 0) {
138 		(void) thr_setspecific(lookup_state_key, NULL);
139 		return (0);
140 	}
141 
142 	if (sema_trywait(sema) == 0) {
143 		(void) thr_setspecific(lookup_state_key, (void*)1);
144 		return (0);
145 	}
146 
147 	return (1);
148 }
149 
150 
151 /*
152  * release clearance
153  */
154 int
155 _nscd_release_clearance(sema_t *sema) {
156 	int	which;
157 
158 	(void) thr_getspecific(lookup_state_key, (void**)&which);
159 	if (which == 0) /* from common pool */ {
160 		(void) sema_post(&common_sema);
161 		return (0);
162 	}
163 
164 	(void) sema_post(sema);
165 	return (1);
166 }
167 
168 static void
169 dozip(void)
170 {
171 	/* not much here */
172 }
173 
174 static void
175 restart_if_cfgfile_changed()
176 {
177 
178 	static mutex_t	nsswitch_lock = DEFAULTMUTEX;
179 	static time_t	last_nsswitch_check = 0;
180 	static time_t	last_nsswitch_modified = 0;
181 	static time_t	last_resolv_modified = 0;
182 	time_t		now = time(NULL);
183 	char		*me = "restart_if_cfgfile_changed";
184 
185 	if (now - last_nsswitch_check <= _NSC_FILE_CHECK_TIME)
186 		return;
187 
188 	(void) mutex_lock(&nsswitch_lock);
189 
190 	if (now - last_nsswitch_check > _NSC_FILE_CHECK_TIME) {
191 		struct stat nss_buf;
192 		struct stat res_buf;
193 
194 		last_nsswitch_check = now;
195 
196 		(void) mutex_unlock(&nsswitch_lock); /* let others continue */
197 
198 		/*
199 		 *  This code keeps us from statting resolv.conf
200 		 *  if it doesn't exist, yet prevents us from ignoring
201 		 *  it if it happens to disappear later on for a bit.
202 		 */
203 
204 		if (last_resolv_modified >= 0) {
205 			if (stat("/etc/resolv.conf", &res_buf) < 0) {
206 				if (last_resolv_modified == 0)
207 				    last_resolv_modified = -1;
208 				else
209 				    res_buf.st_mtime = last_resolv_modified;
210 			} else if (last_resolv_modified == 0) {
211 			    last_resolv_modified = res_buf.st_mtime;
212 			}
213 		}
214 
215 		if (stat("/etc/nsswitch.conf", &nss_buf) < 0) {
216 
217 			/*EMPTY*/;
218 
219 		} else if (last_nsswitch_modified == 0) {
220 
221 			last_nsswitch_modified = nss_buf.st_mtime;
222 
223 		} else if ((last_nsswitch_modified < nss_buf.st_mtime) ||
224 		    ((last_resolv_modified > 0) &&
225 		    (last_resolv_modified < res_buf.st_mtime))) {
226 			static mutex_t exit_lock = DEFAULTMUTEX;
227 			char *fmri;
228 
229 			/*
230 			 * if in self cred mode, kill the forker and
231 			 * child nscds
232 			 */
233 			if (_nscd_is_self_cred_on(0, NULL)) {
234 				_nscd_kill_forker();
235 				_nscd_kill_all_children();
236 			}
237 
238 			/*
239 			 * time for restart
240 			 */
241 			_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_INFO)
242 			(me, "nscd restart due to %s or %s change\n",
243 				"/etc/nsswitch.conf", "resolv.conf");
244 			/*
245 			 * try to restart under smf
246 			 */
247 			if ((fmri = getenv("SMF_FMRI")) == NULL) {
248 				/* not running under smf - reexec */
249 				(void) execv(main_execname, main_argv);
250 				exit(1); /* just in case */
251 			}
252 
253 			/* prevent multiple restarts */
254 			(void) mutex_lock(&exit_lock);
255 
256 			if (smf_restart_instance(fmri) == 0)
257 				(void) sleep(10); /* wait a bit */
258 			exit(1); /* give up waiting for resurrection */
259 		}
260 
261 	} else
262 	    (void) mutex_unlock(&nsswitch_lock);
263 }
264 
265 uid_t
266 _nscd_get_client_euid()
267 {
268 	ucred_t	*uc = NULL;
269 	uid_t	id;
270 	char	*me = "get_client_euid";
271 
272 	if (door_ucred(&uc) != 0) {
273 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
274 		(me, "door_ucred: %s\n", strerror(errno));
275 		return ((uid_t)-1);
276 	}
277 
278 	id = ucred_geteuid(uc);
279 	ucred_free(uc);
280 	return (id);
281 }
282 
283 static void
284 N2N_check_priv(
285 	void			*buf,
286 	char			*dc_str)
287 {
288 	nss_pheader_t		*phdr = (nss_pheader_t *)buf;
289 	ucred_t			*uc = NULL;
290 	const priv_set_t	*eset;
291 	zoneid_t		zoneid;
292 	int			errnum;
293 	char			*me = "N2N_check_priv";
294 
295 	if (door_ucred(&uc) != 0) {
296 		errnum = errno;
297 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
298 		(me, "door_ucred: %s\n", strerror(errno));
299 
300 		NSCD_RETURN_STATUS(phdr, NSS_ERROR, errnum);
301 	}
302 
303 	eset = ucred_getprivset(uc, PRIV_EFFECTIVE);
304 	zoneid = ucred_getzoneid(uc);
305 
306 	if ((zoneid != GLOBAL_ZONEID && zoneid != getzoneid()) ||
307 		eset != NULL ? !priv_ismember(eset, PRIV_SYS_ADMIN) :
308 		ucred_geteuid(uc) != 0) {
309 
310 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ALERT)
311 		(me, "%s call failed(cred): caller pid %d, uid %d, "
312 		"euid %d, zoneid %d\n", dc_str, ucred_getpid(uc),
313 		ucred_getruid(uc), ucred_geteuid(uc), zoneid);
314 		ucred_free(uc);
315 
316 		NSCD_RETURN_STATUS(phdr, NSS_ERROR, EACCES);
317 	}
318 
319 	_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
320 	(me, "nscd received %s cmd from pid %d, uid %d, "
321 	"euid %d, zoneid %d\n", dc_str, ucred_getpid(uc),
322 	ucred_getruid(uc), ucred_geteuid(uc), zoneid);
323 
324 	ucred_free(uc);
325 
326 	NSCD_RETURN_STATUS_SUCCESS(phdr);
327 }
328 
329 static void
330 APP_check_cred(
331 	void		*buf,
332 	pid_t		*pidp,
333 	char		*dc_str)
334 {
335 	nss_pheader_t	*phdr = (nss_pheader_t *)buf;
336 	ucred_t		*uc = NULL;
337 	uid_t		ruid;
338 	uid_t		euid;
339 	int		errnum;
340 	char		*me = "APP_check_cred";
341 
342 	if (door_ucred(&uc) != 0) {
343 		errnum = errno;
344 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
345 		(me, "door_ucred: %s\n", strerror(errno));
346 
347 		NSCD_RETURN_STATUS(phdr, NSS_ERROR, errnum);
348 	}
349 
350 	if (NSS_PACKED_CRED_CHECK(buf, ruid = ucred_getruid(uc),
351 		euid = ucred_geteuid(uc))) {
352 		if (pidp != NULL)
353 			*pidp = ucred_getpid(uc);
354 		ucred_free(uc);
355 
356 		NSCD_RETURN_STATUS_SUCCESS(phdr);
357 	}
358 
359 	_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ALERT)
360 	(me, "%s call failed: caller pid %d, ruid %d, "
361 	"euid %d, header ruid %d, header euid %d\n", dc_str,
362 	(pidp != NULL) ? *pidp : -1, ruid, euid,
363 	((nss_pheader_t *)(buf))->p_ruid, ((nss_pheader_t *)(buf))->p_euid);
364 
365 
366 	ucred_free(uc);
367 
368 	NSCD_RETURN_STATUS(phdr, NSS_ERROR, EACCES);
369 }
370 
371 static void
372 lookup(char *argp, size_t arg_size)
373 {
374 	nsc_lookup_args_t	largs;
375 	char			space[NSCD_LOOKUP_BUFSIZE];
376 	nss_pheader_t		*phdr = (nss_pheader_t *)(void *)argp;
377 
378 	NSCD_ALLOC_LOOKUP_BUFFER(argp, arg_size, phdr, space,
379 		sizeof (space));
380 
381 	(void) memset(&largs, 0, sizeof (largs));
382 	largs.buffer = argp;
383 	largs.bufsize = arg_size;
384 	nsc_lookup(&largs, 0);
385 
386 	/*
387 	 * only the PUN needs to keep track of the
388 	 * activity count to determine when to
389 	 * terminate itself
390 	 */
391 	if (_whoami == NSCD_CHILD) {
392 		(void) mutex_lock(&activity_lock);
393 		++activity;
394 		(void) mutex_unlock(&activity_lock);
395 	}
396 
397 	NSCD_SET_RETURN_ARG(phdr, arg_size);
398 	(void) door_return(argp, arg_size, NULL, 0);
399 }
400 
401 static void
402 getent(char *argp, size_t arg_size)
403 {
404 	char			space[NSCD_LOOKUP_BUFSIZE];
405 	nss_pheader_t		*phdr = (nss_pheader_t *)(void *)argp;
406 
407 	NSCD_ALLOC_LOOKUP_BUFFER(argp, arg_size, phdr,
408 		space, sizeof (space));
409 
410 	nss_pgetent(argp, arg_size);
411 
412 	NSCD_SET_RETURN_ARG(phdr, arg_size);
413 	(void) door_return(argp, arg_size, NULL, 0);
414 }
415 
416 static int
417 is_db_per_user(void *buf, char *dblist)
418 {
419 	nss_pheader_t	*phdr = (nss_pheader_t *)buf;
420 	nss_dbd_t	*pdbd;
421 	char		*dbname, *dbn;
422 	int		len;
423 
424 	/* copy db name into a temp buffer */
425 	pdbd = (nss_dbd_t *)((void *)((char *)buf + phdr->dbd_off));
426 	dbname = (char *)pdbd + pdbd->o_name;
427 	len = strlen(dbname);
428 	dbn = alloca(len + 2);
429 	(void) memcpy(dbn, dbname, len);
430 
431 	/* check if <dbname> + ',' can be found in the dblist string */
432 	dbn[len] = ',';
433 	dbn[len + 1] = '\0';
434 	if (strstr(dblist, dbn) != NULL)
435 		return (1);
436 
437 	/*
438 	 * check if <dbname> can be found in the last part
439 	 * of the dblist string
440 	 */
441 	dbn[len] = '\0';
442 	if (strstr(dblist, dbn) != NULL)
443 		return (1);
444 
445 	return (0);
446 }
447 
448 /*
449  * Check to see if all conditions are met for processing per-user
450  * requests. Returns 1 if yes, -1 if backend is not configured,
451  * 0 otherwise.
452  */
453 static int
454 need_per_user_door(void *buf, int whoami, uid_t uid, char **dblist)
455 {
456 	nss_pheader_t	*phdr = (nss_pheader_t *)buf;
457 
458 	NSCD_SET_STATUS_SUCCESS(phdr);
459 
460 	/* if already a per-user nscd, no need to get per-user door */
461 	if (whoami == NSCD_CHILD)
462 		return (0);
463 
464 	/* forker shouldn't be asked */
465 	if (whoami == NSCD_FORKER) {
466 		NSCD_SET_STATUS(phdr, NSS_ERROR, ENOTSUP);
467 		return (0);
468 	}
469 
470 	/* if door client is root, no need for a per-user door */
471 	if (uid == 0)
472 		return (0);
473 
474 	/*
475 	 * if per-user lookup is not configured, no per-user
476 	 * door available
477 	 */
478 	if (_nscd_is_self_cred_on(0, dblist) == 0)
479 		return (-1);
480 
481 	/*
482 	 * if per-user lookup is not configured for the db,
483 	 * don't bother
484 	 */
485 	if (is_db_per_user(phdr, *dblist) == 0)
486 		return (0);
487 
488 	return (1);
489 }
490 
491 static void
492 if_selfcred_return_per_user_door(char *argp, size_t arg_size,
493 	door_desc_t *dp, int whoami)
494 {
495 	nss_pheader_t	*phdr = (nss_pheader_t *)((void *)argp);
496 	char		*dblist;
497 	int		door = -1;
498 	int		rc = 0;
499 	door_desc_t	desc;
500 	char		space[1024*4];
501 
502 	/*
503 	 * check to see if self-cred is configured and
504 	 * need to return an alternate PUN door
505 	 */
506 	if (per_user_is_on == 1) {
507 		rc = need_per_user_door(argp, whoami,
508 			_nscd_get_client_euid(), &dblist);
509 		if (rc == -1)
510 			per_user_is_on = 0;
511 	}
512 	if (rc <= 0) {
513 		/*
514 		 * self-cred not configured, and no error detected,
515 		 * return to continue the door call processing
516 		 */
517 		if (NSCD_STATUS_IS_OK(phdr))
518 			return;
519 		else
520 			/*
521 			 * configured but error detected,
522 			 * stop the door call processing
523 			 */
524 			(void) door_return(argp, phdr->data_off, NULL, 0);
525 	}
526 
527 	/* get the alternate PUN door */
528 	_nscd_proc_alt_get(argp, &door);
529 	if (NSCD_GET_STATUS(phdr) != NSS_ALTRETRY) {
530 		(void) door_return(argp, phdr->data_off, NULL, 0);
531 	}
532 
533 	/* return the alternate door descriptor */
534 	(void) memcpy(space, phdr, NSCD_PHDR_LEN(phdr));
535 	argp = space;
536 	phdr = (nss_pheader_t *)(void *)space;
537 	dp = &desc;
538 	dp->d_attributes = DOOR_DESCRIPTOR;
539 	dp->d_data.d_desc.d_descriptor = door;
540 	phdr->data_len = strlen(dblist) + 1;
541 	(void) strcpy(((char *)phdr) + NSCD_PHDR_LEN(phdr), dblist);
542 
543 	arg_size = NSCD_PHDR_LEN(phdr) + NSCD_DATA_LEN(phdr);
544 	(void) door_return(argp, arg_size, dp, 1);
545 }
546 
547 /*ARGSUSED*/
548 static void
549 switcher(void *cookie, char *argp, size_t arg_size,
550     door_desc_t *dp, uint_t n_desc)
551 {
552 	int			iam;
553 	pid_t			ent_pid = -1;
554 	nss_pheader_t		*phdr = (nss_pheader_t *)((void *)argp);
555 	void			*uptr;
556 	int			buflen, len;
557 	int			callnum;
558 	char			*me = "switcher";
559 
560 	_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
561 	(me, "switcher ...\n");
562 
563 	if (argp == DOOR_UNREF_DATA) {
564 		(void) printf("Door Slam... exiting\n");
565 		exit(0);
566 	}
567 
568 	if (argp == NULL) { /* empty door call */
569 		(void) door_return(NULL, 0, 0, 0); /* return the favor */
570 	}
571 
572 	/*
573 	 *  need to restart if main nscd and config file(s) changed
574 	 */
575 	if (_whoami == NSCD_MAIN)
576 		restart_if_cfgfile_changed();
577 
578 	if ((phdr->nsc_callnumber & NSCDV2CATMASK) == NSCD_CALLCAT_APP) {
579 		switch (phdr->nsc_callnumber) {
580 		case NSCD_SEARCH:
581 
582 		/* if a fallback to main nscd, skip per-user setup */
583 		if (phdr->p_status != NSS_ALTRETRY)
584 			if_selfcred_return_per_user_door(argp, arg_size,
585 				dp, _whoami);
586 		lookup(argp, arg_size);
587 
588 		break;
589 
590 		case NSCD_SETENT:
591 
592 		APP_check_cred(argp, &ent_pid, "NSCD_SETENT");
593 		if (NSCD_STATUS_IS_OK(phdr)) {
594 			if_selfcred_return_per_user_door(argp, arg_size,
595 				dp, _whoami);
596 			nss_psetent(argp, arg_size, ent_pid);
597 		}
598 		break;
599 
600 		case NSCD_GETENT:
601 
602 		getent(argp, arg_size);
603 		break;
604 
605 		case NSCD_ENDENT:
606 
607 		nss_pendent(argp, arg_size);
608 		break;
609 
610 		case NSCD_PUT:
611 
612 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
613 		(me, "door call NSCD_PUT not supported yet\n");
614 
615 		NSCD_SET_STATUS(phdr, NSS_ERROR, ENOTSUP);
616 		break;
617 
618 		case NSCD_GETHINTS:
619 
620 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
621 		(me, "door call NSCD_GETHINTS not supported yet\n");
622 
623 		NSCD_SET_STATUS(phdr, NSS_ERROR, ENOTSUP);
624 		break;
625 
626 		default:
627 
628 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
629 		(me, "Unknown name service door call op %x\n",
630 		phdr->nsc_callnumber);
631 
632 		NSCD_SET_STATUS(phdr, NSS_ERROR, EINVAL);
633 		break;
634 		}
635 
636 		(void) door_return(argp, arg_size, NULL, 0);
637 	}
638 
639 	iam = NSCD_MAIN;
640 	callnum = phdr->nsc_callnumber & ~NSCD_WHOAMI;
641 	if (callnum == NSCD_IMHERE ||
642 		callnum == NSCD_PULSE || callnum == NSCD_FORK)
643 		iam = phdr->nsc_callnumber & NSCD_WHOAMI;
644 	else
645 		callnum = phdr->nsc_callnumber;
646 
647 	/* nscd -> nscd v2 calls */
648 	switch (callnum) {
649 
650 	case NSCD_PING:
651 		NSCD_SET_STATUS_SUCCESS(phdr);
652 		break;
653 
654 	case NSCD_IMHERE:
655 		_nscd_proc_iamhere(argp, dp, n_desc, iam);
656 		break;
657 
658 	case NSCD_PULSE:
659 		N2N_check_priv(argp, "NSCD_PULSE");
660 		if (NSCD_STATUS_IS_OK(phdr))
661 			_nscd_proc_pulse(argp, iam);
662 		break;
663 
664 	case NSCD_FORK:
665 		N2N_check_priv(argp, "NSCD_FORK");
666 		if (NSCD_STATUS_IS_OK(phdr))
667 			_nscd_proc_fork(argp, iam);
668 		break;
669 
670 	case NSCD_KILL:
671 		N2N_check_priv(argp, "NSCD_KILL");
672 		if (NSCD_STATUS_IS_OK(phdr))
673 			exit(0);
674 		break;
675 
676 	case NSCD_REFRESH:
677 		if (_nscd_refresh() != NSCD_SUCCESS)
678 			exit(1);
679 		NSCD_SET_STATUS_SUCCESS(phdr);
680 		break;
681 
682 	case NSCD_GETPUADMIN:
683 
684 		if (_nscd_is_self_cred_on(0, NULL)) {
685 			_nscd_peruser_getadmin(argp, sizeof (nscd_admin_t));
686 		} else {
687 			NSCD_SET_N2N_STATUS(phdr, NSS_NSCD_PRIV, 0,
688 				NSCD_SELF_CRED_NOT_CONFIGURED);
689 		}
690 		break;
691 
692 	case NSCD_GETADMIN:
693 
694 		len = _nscd_door_getadmin((void *)argp);
695 		if (len == 0)
696 			break;
697 
698 		/* size of door buffer not big enough, allocate one */
699 		NSCD_ALLOC_DOORBUF(NSCD_GETADMIN, len, uptr, buflen);
700 
701 		/* copy packed header */
702 		*(nss_pheader_t *)uptr = *(nss_pheader_t *)((void *)argp);
703 
704 		/* set new buffer size */
705 		((nss_pheader_t *)uptr)->pbufsiz = buflen;
706 
707 		/* try one more time */
708 		(void) _nscd_door_getadmin((void *)uptr);
709 		(void) door_return(uptr, buflen, NULL, 0);
710 		break;
711 
712 	case NSCD_SETADMIN:
713 		N2N_check_priv(argp, "NSCD_SETADMIN");
714 		if (NSCD_STATUS_IS_OK(phdr))
715 			_nscd_door_setadmin(argp);
716 		break;
717 
718 	case NSCD_KILLSERVER:
719 		N2N_check_priv(argp, "NSCD_KILLSERVER");
720 		if (NSCD_STATUS_IS_OK(phdr)) {
721 			/* also kill the forker nscd if one is running */
722 			_nscd_kill_forker();
723 			exit(0);
724 		}
725 		break;
726 
727 	default:
728 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
729 		(me, "Unknown name service door call op %d\n",
730 			phdr->nsc_callnumber);
731 
732 		NSCD_SET_STATUS(phdr, NSS_ERROR, EINVAL);
733 
734 		(void) door_return(argp, arg_size, NULL, 0);
735 		break;
736 
737 	}
738 	(void) door_return(argp, arg_size, NULL, 0);
739 }
740 
741 int
742 _nscd_setup_server(char *execname, char **argv)
743 {
744 
745 	int		fd;
746 	int		errnum;
747 	int		bind_failed = 0;
748 	struct stat	buf;
749 	sigset_t	myset;
750 	struct sigaction action;
751 	char		*me = "_nscd_setup_server";
752 
753 	main_execname = execname;
754 	main_argv = argv;
755 
756 	keep_open_dns_socket();
757 
758 	/*
759 	 * the max number of server threads should be fixed now, so
760 	 * set flag to indicate that no in-flight change is allowed
761 	 */
762 	max_servers_set = 1;
763 
764 	(void) thr_keycreate(&lookup_state_key, NULL);
765 	(void) sema_init(&common_sema,
766 			frontend_cfg_g.common_worker_threads,
767 			USYNC_THREAD, 0);
768 
769 	/* Establish server thread pool */
770 	(void) door_server_create(server_create);
771 	if (thr_keycreate(&server_key, server_destroy) != 0) {
772 		errnum = errno;
773 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
774 		(me, "thr_keycreate (server thread): %s\n",
775 			strerror(errnum));
776 		return (-1);
777 	}
778 
779 	/* Create a door */
780 	if ((fd = door_create(switcher, NAME_SERVICE_DOOR_COOKIE,
781 	    DOOR_UNREF | DOOR_NO_CANCEL)) < 0) {
782 		errnum = errno;
783 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
784 		(me, "door_create: %s\n", strerror(errnum));
785 		return (-1);
786 	}
787 
788 	/* if not main nscd, no more setup to do */
789 	if (_whoami != NSCD_MAIN)
790 		return (fd);
791 
792 	/* bind to file system */
793 	if (is_system_labeled()) {
794 		if (stat(TSOL_NAME_SERVICE_DOOR, &buf) < 0) {
795 			int newfd;
796 			if ((newfd = creat(TSOL_NAME_SERVICE_DOOR, 0444)) < 0) {
797 				errnum = errno;
798 				_NSCD_LOG(NSCD_LOG_FRONT_END,
799 					NSCD_LOG_LEVEL_ERROR)
800 				(me, "Cannot create %s: %s\n",
801 					TSOL_NAME_SERVICE_DOOR,
802 					strerror(errnum));
803 				bind_failed = 1;
804 			}
805 			(void) close(newfd);
806 		}
807 		if (symlink(TSOL_NAME_SERVICE_DOOR, NAME_SERVICE_DOOR) != 0) {
808 			if (errno != EEXIST) {
809 				errnum = errno;
810 				_NSCD_LOG(NSCD_LOG_FRONT_END,
811 					NSCD_LOG_LEVEL_ERROR)
812 				(me, "Cannot symlink %s: %s\n",
813 					NAME_SERVICE_DOOR,
814 					strerror(errnum));
815 				bind_failed = 1;
816 			}
817 		}
818 	} else if (stat(NAME_SERVICE_DOOR, &buf) < 0) {
819 		int newfd;
820 		if ((newfd = creat(NAME_SERVICE_DOOR, 0444)) < 0) {
821 			errnum = errno;
822 			_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
823 			(me, "Cannot create %s: %s\n", NAME_SERVICE_DOOR,
824 				strerror(errnum));
825 			bind_failed = 1;
826 		}
827 		(void) close(newfd);
828 	}
829 
830 	if (bind_failed == 1) {
831 		(void) door_revoke(fd);
832 		return (-1);
833 	}
834 
835 	if (fattach(fd, NAME_SERVICE_DOOR) < 0) {
836 		if ((errno != EBUSY) ||
837 		(fdetach(NAME_SERVICE_DOOR) <  0) ||
838 		(fattach(fd, NAME_SERVICE_DOOR) < 0)) {
839 			errnum = errno;
840 			_NSCD_LOG(NSCD_LOG_FRONT_END,
841 				NSCD_LOG_LEVEL_ERROR)
842 			(me, "fattach: %s\n", strerror(errnum));
843 			(void) door_revoke(fd);
844 			return (-1);
845 		}
846 	}
847 
848 	/*
849 	 * kick off routing socket monitor thread
850 	 */
851 	if (thr_create(NULL, NULL,
852 		(void *(*)(void *))rts_mon, 0, 0, NULL) != 0) {
853 		errnum = errno;
854 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
855 		(me, "thr_create (routing socket monitor): %s\n",
856 			strerror(errnum));
857 
858 		(void) door_revoke(fd);
859 		return (-1);
860 	}
861 
862 	/*
863 	 * set up signal handler for SIGHUP
864 	 */
865 	action.sa_handler = dozip;
866 	action.sa_flags = 0;
867 	(void) sigemptyset(&action.sa_mask);
868 	(void) sigemptyset(&myset);
869 	(void) sigaddset(&myset, SIGHUP);
870 
871 	if (sigaction(SIGHUP, &action, NULL) < 0) {
872 		errnum = errno;
873 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
874 		(me, "sigaction (SIGHUP): %s\n", strerror(errnum));
875 
876 		(void) door_revoke(fd);
877 		return (-1);
878 	}
879 
880 	return (fd);
881 }
882 
883 int
884 _nscd_setup_child_server(int did)
885 {
886 
887 	int		errnum;
888 	int		fd;
889 	nscd_rc_t	rc;
890 	char		*me = "_nscd_setup_child_server";
891 
892 	/* Re-establish our own server thread pool */
893 	(void) door_server_create(server_create);
894 	if (thr_keycreate(&server_key, server_destroy) != 0) {
895 		errnum = errno;
896 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
897 		(me, "thr_keycreate failed: %s", strerror(errnum));
898 		return (-1);
899 	}
900 
901 	/*
902 	 * Create a new door.
903 	 * Keep DOOR_REFUSE_DESC (self-cred nscds don't fork)
904 	 */
905 	(void) close(did);
906 	if ((fd = door_create(switcher,
907 		NAME_SERVICE_DOOR_COOKIE,
908 		DOOR_REFUSE_DESC|DOOR_UNREF|DOOR_NO_CANCEL)) < 0) {
909 		errnum = errno;
910 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_DEBUG)
911 		(me, "door_create failed: %s", strerror(errnum));
912 		return (-1);
913 	}
914 
915 	/*
916 	 * kick off routing socket monitor thread
917 	 */
918 	if (thr_create(NULL, NULL,
919 		(void *(*)(void *))rts_mon, 0, 0, NULL) != 0) {
920 		errnum = errno;
921 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
922 		(me, "thr_create (routing socket monitor): %s\n",
923 			strerror(errnum));
924 		(void) door_revoke(fd);
925 		return (-1);
926 	}
927 
928 	/*
929 	 * start monitoring the states of the name service clients
930 	 */
931 	rc = _nscd_init_smf_monitor();
932 	if (rc != NSCD_SUCCESS) {
933 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
934 	(me, "unable to start the SMF monitor (rc = %d)\n", rc);
935 
936 		(void) door_revoke(fd);
937 		return (-1);
938 	}
939 
940 	return (fd);
941 }
942 
943 nscd_rc_t
944 _nscd_alloc_frontend_cfg()
945 {
946 	frontend_cfg  = calloc(NSCD_NUM_DB, sizeof (nscd_cfg_frontend_t));
947 	if (frontend_cfg == NULL)
948 		return (NSCD_NO_MEMORY);
949 
950 	return (NSCD_SUCCESS);
951 }
952 
953 
954 /* ARGSUSED */
955 nscd_rc_t
956 _nscd_cfg_frontend_notify(
957 	void				*data,
958 	struct nscd_cfg_param_desc	*pdesc,
959 	nscd_cfg_id_t			*nswdb,
960 	nscd_cfg_flag_t			dflag,
961 	nscd_cfg_error_t		**errorp,
962 	void				*cookie)
963 {
964 	void				*dp;
965 
966 	/*
967 	 * At init time, the whole group of config params are received.
968 	 * At update time, group or individual parameter value could
969 	 * be received.
970 	 */
971 
972 	if (_nscd_cfg_flag_is_set(dflag, NSCD_CFG_DFLAG_INIT) ||
973 		_nscd_cfg_flag_is_set(dflag, NSCD_CFG_DFLAG_GROUP)) {
974 		/*
975 		 * group data is received, copy in the
976 		 * entire strcture
977 		 */
978 		if (_nscd_cfg_flag_is_set(pdesc->pflag,
979 			NSCD_CFG_PFLAG_GLOBAL))
980 			frontend_cfg_g =
981 				*(nscd_cfg_global_frontend_t *)data;
982 		else
983 			frontend_cfg[nswdb->index] =
984 				*(nscd_cfg_frontend_t *)data;
985 
986 	} else {
987 		/*
988 		 * individual paramater is received: copy in the
989 		 * parameter value.
990 		 */
991 		if (_nscd_cfg_flag_is_set(pdesc->pflag,
992 			NSCD_CFG_PFLAG_GLOBAL))
993 			dp = (char *)&frontend_cfg_g + pdesc->p_offset;
994 		else
995 			dp = (char *)&frontend_cfg[nswdb->index] +
996 				pdesc->p_offset;
997 		(void) memcpy(dp, data, pdesc->p_size);
998 	}
999 
1000 	return (NSCD_SUCCESS);
1001 }
1002 
1003 /* ARGSUSED */
1004 nscd_rc_t
1005 _nscd_cfg_frontend_verify(
1006 	void				*data,
1007 	struct	nscd_cfg_param_desc	*pdesc,
1008 	nscd_cfg_id_t			*nswdb,
1009 	nscd_cfg_flag_t			dflag,
1010 	nscd_cfg_error_t		**errorp,
1011 	void				**cookie)
1012 {
1013 
1014 	char				*me = "_nscd_cfg_frontend_verify";
1015 
1016 	/*
1017 	 * if max. number of server threads is set and in effect,
1018 	 * don't allow changing of the frontend configuration
1019 	 */
1020 	if (max_servers_set) {
1021 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_INFO)
1022 	(me, "changing of the frontend configuration not allowed now");
1023 
1024 		return (NSCD_CFG_CHANGE_NOT_ALLOWED);
1025 	}
1026 
1027 	return (NSCD_SUCCESS);
1028 }
1029 
1030 /* ARGSUSED */
1031 nscd_rc_t
1032 _nscd_cfg_frontend_get_stat(
1033 	void				**stat,
1034 	struct nscd_cfg_stat_desc	*sdesc,
1035 	nscd_cfg_id_t			*nswdb,
1036 	nscd_cfg_flag_t			*dflag,
1037 	void				(**free_stat)(void *stat),
1038 	nscd_cfg_error_t		**errorp)
1039 {
1040 	return (NSCD_SUCCESS);
1041 }
1042 
1043 void
1044 _nscd_init_cache_sema(sema_t *sema, char *cache_name)
1045 {
1046 	int	i, j;
1047 	char	*dbn;
1048 
1049 	if (max_servers == 0)
1050 		max_servers = frontend_cfg_g.common_worker_threads +
1051 		frontend_cfg_g.cache_hit_threads;
1052 
1053 	for (i = 0; i < NSCD_NUM_DB; i++) {
1054 
1055 		dbn = NSCD_NSW_DB_NAME(i);
1056 		if (strcasecmp(dbn, cache_name) == 0) {
1057 			j = frontend_cfg[i].worker_thread_per_nsw_db;
1058 			(void) sema_init(sema, j, USYNC_THREAD, 0);
1059 			max_servers += j;
1060 			break;
1061 		}
1062 	}
1063 }
1064 
1065 /*
1066  * Monitor the routing socket.  Address lists stored in the ipnodes
1067  * cache are sorted based on destination address selection rules,
1068  * so when things change that could affect that sorting (interfaces
1069  * go up or down, flags change, etc.), we clear that cache so the
1070  * list will be re-ordered the next time the hostname is resolved.
1071  */
1072 static void
1073 rts_mon(void)
1074 {
1075 	int	rt_sock, rdlen, idx;
1076 	union {
1077 		struct {
1078 			struct rt_msghdr rtm;
1079 			struct sockaddr_storage addrs[RTA_NUMBITS];
1080 		} r;
1081 		struct if_msghdr ifm;
1082 		struct ifa_msghdr ifam;
1083 	} mbuf;
1084 	struct ifa_msghdr *ifam = &mbuf.ifam;
1085 	char	*me = "rts_mon";
1086 
1087 	rt_sock = socket(PF_ROUTE, SOCK_RAW, 0);
1088 	if (rt_sock < 0) {
1089 		_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
1090 		(me, "Failed to open routing socket: %s\n", strerror(errno));
1091 		thr_exit(0);
1092 	}
1093 
1094 	for (;;) {
1095 		rdlen = read(rt_sock, &mbuf, sizeof (mbuf));
1096 		if (rdlen <= 0) {
1097 			if (rdlen == 0 || (errno != EINTR && errno != EAGAIN)) {
1098 				_NSCD_LOG(NSCD_LOG_FRONT_END,
1099 					NSCD_LOG_LEVEL_ERROR)
1100 				(me, "routing socket read: %s\n",
1101 					strerror(errno));
1102 				thr_exit(0);
1103 			}
1104 			continue;
1105 		}
1106 		if (ifam->ifam_version != RTM_VERSION) {
1107 				_NSCD_LOG(NSCD_LOG_FRONT_END,
1108 					NSCD_LOG_LEVEL_ERROR)
1109 				(me, "rx unknown version (%d) on "
1110 					"routing socket.\n",
1111 					ifam->ifam_version);
1112 			continue;
1113 		}
1114 		switch (ifam->ifam_type) {
1115 		case RTM_NEWADDR:
1116 		case RTM_DELADDR:
1117 			/* if no ipnodes cache, then nothing to do */
1118 			idx = get_cache_idx("ipnodes");
1119 			if (cache_ctx_p[idx] == NULL ||
1120 				cache_ctx_p[idx]->reaper_on != nscd_true)
1121 				break;
1122 			nsc_invalidate(cache_ctx_p[idx], NULL, NULL);
1123 			break;
1124 		case RTM_ADD:
1125 		case RTM_DELETE:
1126 		case RTM_CHANGE:
1127 		case RTM_GET:
1128 		case RTM_LOSING:
1129 		case RTM_REDIRECT:
1130 		case RTM_MISS:
1131 		case RTM_LOCK:
1132 		case RTM_OLDADD:
1133 		case RTM_OLDDEL:
1134 		case RTM_RESOLVE:
1135 		case RTM_IFINFO:
1136 			break;
1137 		default:
1138 			_NSCD_LOG(NSCD_LOG_FRONT_END, NSCD_LOG_LEVEL_ERROR)
1139 			(me, "rx unknown msg type (%d) on routing socket.\n",
1140 			    ifam->ifam_type);
1141 			break;
1142 		}
1143 	}
1144 }
1145 
1146 static void
1147 keep_open_dns_socket(void)
1148 {
1149 	_res.options |= RES_STAYOPEN; /* just keep this udp socket open */
1150 }
1151