xref: /titanic_44/usr/src/cmd/ldapcachemgr/cachemgr.c (revision c651b32e568cbf9b715a127805fe1cba321be5b0)
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 2008 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 /*
29  * Simple doors ldap cache daemon
30  */
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <signal.h>
35 #include <door.h>
36 #include <time.h>
37 #include <string.h>
38 #include <strings.h>
39 #include <libintl.h>
40 #include <sys/stat.h>
41 #include <sys/time.h>
42 #include <sys/wait.h>
43 #include <stdlib.h>
44 #include <errno.h>
45 #include <pthread.h>
46 #include <thread.h>
47 #include <stdarg.h>
48 #include <fcntl.h>
49 #include <assert.h>
50 #include <unistd.h>
51 #include <memory.h>
52 #include <sys/types.h>
53 #include <syslog.h>
54 #include <locale.h>	/* LC_ALL */
55 
56 #include <alloca.h>
57 #include <ucontext.h>
58 
59 #include "getxby_door.h"
60 #include "cachemgr.h"
61 
62 static void	detachfromtty();
63 admin_t		current_admin;
64 static int	will_become_server;
65 
66 static void switcher(void *cookie, char *argp, size_t arg_size,
67 			door_desc_t *dp, uint_t n_desc);
68 static void usage(char *s);
69 static int cachemgr_set_lf(admin_t *ptr, char *logfile);
70 static int client_getadmin(admin_t *ptr);
71 static int setadmin(ldap_call_t *ptr);
72 static  int client_setadmin(admin_t *ptr);
73 static int client_showstats(admin_t *ptr);
74 static int is_root(int free_uc, char *dc_str, ucred_t **uc);
75 
76 #ifdef SLP
77 int			use_slp = 0;
78 static unsigned int	refresh = 10800;	/* dynamic discovery interval */
79 #endif /* SLP */
80 
81 static ldap_stat_t *
82 getcacheptr(char *s)
83 {
84 	static const char *caches[1] = {"ldap"};
85 
86 	if (strncmp(caches[0], s, strlen(caches[0])) == 0)
87 		return (&current_admin.ldap_stat);
88 
89 	return (NULL);
90 }
91 
92 char *
93 getcacheopt(char *s)
94 {
95 	while (*s && *s != ',')
96 		s++;
97 	return ((*s == ',') ? (s + 1) : NULL);
98 }
99 
100 /*
101  *  This is here to prevent the ldap_cachemgr becomes
102  *  daemonlized to early to soon during boot time.
103  *  This causes problems during boot when automounter
104  *  and others try to use libsldap before ldap_cachemgr
105  *  finishes walking the server list.
106  */
107 static void
108 sig_ok_to_exit(int signo)
109 {
110 	if (signo == SIGUSR1) {
111 		logit("sig_ok_to_exit(): parent exiting...\n");
112 		exit(0);
113 	} else {
114 		logit("sig_ok_to_exit(): invalid signal(%d) received.\n",
115 		    signo);
116 		syslog(LOG_ERR, gettext("ldap_cachemgr: "
117 		    "invalid signal(%d) received."), signo);
118 		exit(1);
119 	}
120 }
121 #define	LDAP_TABLES		1	/* ldap */
122 #define	TABLE_THREADS		10
123 #define	COMMON_THREADS		20
124 #define	CACHE_MISS_THREADS	(COMMON_THREADS + LDAP_TABLES * TABLE_THREADS)
125 #define	CACHE_HIT_THREADS	20
126 /*
127  * There is only one thread handling GETSTATUSCHANGE START from main nscd
128  * most of time. But it could happen that a main nscd is restarted, old main
129  * nscd's handling thread is still alive when new main nscd starts and sends
130  * START, or old main dies. STOP is not sent in both cases.
131  * The main nscd requires 2 threads to handle START and STOP. So max number
132  * of change threads is set to 4.
133  */
134 #define	MAX_CHG_THREADS		4
135 #define	MAX_SERVER_THREADS	(CACHE_HIT_THREADS + CACHE_MISS_THREADS + \
136 				MAX_CHG_THREADS)
137 
138 static sema_t common_sema;
139 static sema_t ldap_sema;
140 static thread_key_t lookup_state_key;
141 static int chg_threads_num = 0;
142 static mutex_t chg_threads_num_lock = DEFAULTMUTEX;
143 
144 static void
145 initialize_lookup_clearance()
146 {
147 	(void) thr_keycreate(&lookup_state_key, NULL);
148 	(void) sema_init(&common_sema, COMMON_THREADS, USYNC_THREAD, 0);
149 	(void) sema_init(&ldap_sema, TABLE_THREADS, USYNC_THREAD, 0);
150 }
151 
152 int
153 get_clearance(int callnumber)
154 {
155 	sema_t	*table_sema = NULL;
156 	char	*tab;
157 
158 	if (sema_trywait(&common_sema) == 0) {
159 		(void) thr_setspecific(lookup_state_key, NULL);
160 		return (0);
161 	}
162 
163 	switch (callnumber) {
164 		case GETLDAPCONFIG:
165 			tab = "ldap";
166 			table_sema = &ldap_sema;
167 			break;
168 		default:
169 			logit("Internal Error: get_clearance\n");
170 			break;
171 	}
172 
173 	if (sema_trywait(table_sema) == 0) {
174 		(void) thr_setspecific(lookup_state_key, (void*)1);
175 		return (0);
176 	}
177 
178 	if (current_admin.debug_level >= DBG_CANT_FIND) {
179 		logit("get_clearance: throttling load for %s table\n", tab);
180 	}
181 
182 	return (-1);
183 }
184 
185 int
186 release_clearance(int callnumber)
187 {
188 	int	which;
189 	sema_t	*table_sema = NULL;
190 
191 	(void) thr_getspecific(lookup_state_key, (void**)&which);
192 	if (which == 0) /* from common pool */ {
193 		(void) sema_post(&common_sema);
194 		return (0);
195 	}
196 
197 	switch (callnumber) {
198 		case GETLDAPCONFIG:
199 			table_sema = &ldap_sema;
200 			break;
201 		default:
202 			logit("Internal Error: release_clearance\n");
203 			break;
204 	}
205 	(void) sema_post(table_sema);
206 
207 	return (0);
208 }
209 
210 
211 static mutex_t		create_lock;
212 static int		num_servers = 0;
213 static thread_key_t	server_key;
214 
215 
216 /*
217  * Bind a TSD value to a server thread. This enables the destructor to
218  * be called if/when this thread exits.  This would be a programming error,
219  * but better safe than sorry.
220  */
221 
222 /*ARGSUSED*/
223 static void *
224 server_tsd_bind(void *arg)
225 {
226 	static void	*value = 0;
227 
228 	/*
229 	 * disable cancellation to prevent hangs when server
230 	 * threads disappear
231 	 */
232 
233 	(void) thr_setspecific(server_key, value);
234 	(void) door_return(NULL, 0, NULL, 0);
235 
236 	return (value);
237 }
238 
239 /*
240  * Server threads are created here.
241  */
242 
243 /*ARGSUSED*/
244 static void
245 server_create(door_info_t *dip)
246 {
247 	(void) mutex_lock(&create_lock);
248 	if (++num_servers > MAX_SERVER_THREADS) {
249 		num_servers--;
250 		(void) mutex_unlock(&create_lock);
251 		return;
252 	}
253 	(void) mutex_unlock(&create_lock);
254 	(void) thr_create(NULL, 0, server_tsd_bind, NULL,
255 	    THR_BOUND|THR_DETACHED, NULL);
256 }
257 
258 /*
259  * Server thread are destroyed here
260  */
261 
262 /*ARGSUSED*/
263 static void
264 server_destroy(void *arg)
265 {
266 	(void) mutex_lock(&create_lock);
267 	num_servers--;
268 	(void) mutex_unlock(&create_lock);
269 }
270 
271 int
272 main(int argc, char ** argv)
273 {
274 	int			did;
275 	int			opt;
276 	int			errflg = 0;
277 	int			showstats = 0;
278 	int			doset = 0;
279 	int			dofg = 0;
280 	struct stat		buf;
281 	sigset_t		myset;
282 	struct sigaction	sighupaction;
283 	static void		client_killserver();
284 	int			debug_level = 0;
285 
286 	/* setup for localization */
287 	(void) setlocale(LC_ALL, "");
288 	(void) textdomain(TEXT_DOMAIN);
289 
290 	openlog("ldap_cachemgr", LOG_PID, LOG_DAEMON);
291 
292 	if (chdir(NSLDAPDIRECTORY) < 0) {
293 		(void) fprintf(stderr, gettext("chdir(\"%s\") failed: %s\n"),
294 		    NSLDAPDIRECTORY, strerror(errno));
295 		exit(1);
296 	}
297 
298 	/*
299 	 * Correctly set file mode creation mask, so to make the new files
300 	 * created for door calls being readable by all.
301 	 */
302 	(void) umask(0);
303 
304 	/*
305 	 *  Special case non-root user here -	he/she/they/it can just print
306 	 *					stats
307 	 */
308 
309 	if (geteuid()) {
310 		if (argc != 2 || strcmp(argv[1], "-g")) {
311 			(void) fprintf(stderr,
312 			    gettext("Must be root to use any option "
313 			    "other than -g.\n\n"));
314 			usage(argv[0]);
315 		}
316 
317 		if ((__ns_ldap_cache_ping() != NS_CACHE_SUCCESS) ||
318 		    (client_getadmin(&current_admin) != 0)) {
319 			(void) fprintf(stderr,
320 			    gettext("%s doesn't appear to be running.\n"),
321 			    argv[0]);
322 			exit(1);
323 		}
324 		(void) client_showstats(&current_admin);
325 		exit(0);
326 	}
327 
328 
329 
330 	/*
331 	 *  Determine if there is already a daemon running
332 	 */
333 
334 	will_become_server = (__ns_ldap_cache_ping() != NS_CACHE_SUCCESS);
335 
336 	/*
337 	 *  load normal config file
338 	 */
339 
340 	if (will_become_server) {
341 		static const ldap_stat_t defaults = {
342 			0,		/* stat */
343 			DEFAULTTTL};	/* ttl */
344 
345 		current_admin.ldap_stat = defaults;
346 		(void) strcpy(current_admin.logfile, LOGFILE);
347 	} else {
348 		if (client_getadmin(&current_admin)) {
349 			(void) fprintf(stderr, gettext("Cannot contact %s "
350 			    "properly(?)\n"), argv[0]);
351 			exit(1);
352 		}
353 	}
354 
355 #ifndef SLP
356 	while ((opt = getopt(argc, argv, "fKgl:r:d:")) != EOF) {
357 #else
358 	while ((opt = getopt(argc, argv, "fKgs:l:r:d:")) != EOF) {
359 #endif /* SLP */
360 		ldap_stat_t	*cache;
361 
362 		switch (opt) {
363 		case 'K':
364 			client_killserver();
365 			exit(0);
366 			break;
367 		case 'g':
368 			showstats++;
369 			break;
370 		case 'f':
371 			dofg++;
372 			break;
373 		case 'r':
374 			doset++;
375 			cache = getcacheptr("ldap");
376 			if (!optarg) {
377 				errflg++;
378 				break;
379 			}
380 			cache->ldap_ttl = atoi(optarg);
381 			break;
382 		case 'l':
383 			doset++;
384 			(void) strlcpy(current_admin.logfile,
385 			    optarg, sizeof (current_admin.logfile));
386 			break;
387 		case 'd':
388 			doset++;
389 			debug_level = atoi(optarg);
390 			break;
391 #ifdef SLP
392 		case 's':	/* undocumented: use dynamic (SLP) config */
393 			use_slp = 1;
394 			break;
395 #endif /* SLP */
396 		default:
397 			errflg++;
398 			break;
399 		}
400 	}
401 
402 	if (errflg)
403 		usage(argv[0]);
404 
405 	/*
406 	 * will not show statistics if no daemon running
407 	 */
408 	if (will_become_server && showstats) {
409 		(void) fprintf(stderr,
410 		    gettext("%s doesn't appear to be running.\n"),
411 		    argv[0]);
412 		exit(1);
413 	}
414 
415 	if (!will_become_server) {
416 		if (showstats) {
417 			(void) client_showstats(&current_admin);
418 		}
419 		if (doset) {
420 			current_admin.debug_level = debug_level;
421 			if (client_setadmin(&current_admin) < 0) {
422 				(void) fprintf(stderr,
423 				    gettext("Error during admin call\n"));
424 				exit(1);
425 			}
426 		}
427 		if (!showstats && !doset) {
428 			(void) fprintf(stderr,
429 			gettext("%s already running....use '%s "
430 			    "-K' to stop\n"), argv[0], argv[0]);
431 		}
432 		exit(0);
433 	}
434 
435 	/*
436 	 *   daemon from here on
437 	 */
438 
439 	if (debug_level) {
440 		/*
441 		 * we're debugging...
442 		 */
443 		if (strlen(current_admin.logfile) == 0)
444 			/*
445 			 * no specified log file
446 			 */
447 			(void) strcpy(current_admin.logfile, LOGFILE);
448 		else
449 			(void) cachemgr_set_lf(&current_admin,
450 			    current_admin.logfile);
451 		/*
452 		 * validate the range of debug level number
453 		 * and set the number to current_admin.debug_level
454 		 */
455 		if (cachemgr_set_dl(&current_admin, debug_level) < 0) {
456 				/*
457 				 * print error messages to the screen
458 				 * cachemgr_set_dl prints msgs to cachemgr.log
459 				 * only
460 				 */
461 				(void) fprintf(stderr,
462 				gettext("Incorrect Debug Level: %d\n"
463 				"It should be between %d and %d\n"),
464 				    debug_level, DBG_OFF, MAXDEBUG);
465 			exit(-1);
466 		}
467 	} else {
468 		if (strlen(current_admin.logfile) == 0)
469 			(void) strcpy(current_admin.logfile, "/dev/null");
470 			(void) cachemgr_set_lf(&current_admin,
471 			    current_admin.logfile);
472 	}
473 
474 	if (dofg == 0)
475 		detachfromtty(argv[0]);
476 
477 	/*
478 	 * perform some initialization
479 	 */
480 
481 	initialize_lookup_clearance();
482 
483 	if (getldap_init() != 0)
484 		exit(-1);
485 
486 	/*
487 	 * Establish our own server thread pool
488 	 */
489 
490 	(void) door_server_create(server_create);
491 	if (thr_keycreate(&server_key, server_destroy) != 0) {
492 		logit("thr_keycreate() call failed\n");
493 		syslog(LOG_ERR,
494 		    gettext("ldap_cachemgr: thr_keycreate() call failed"));
495 		perror("thr_keycreate");
496 		exit(-1);
497 	}
498 
499 	/*
500 	 * Create a door
501 	 */
502 
503 	if ((did = door_create(switcher, LDAP_CACHE_DOOR_COOKIE,
504 	    DOOR_UNREF | DOOR_REFUSE_DESC | DOOR_NO_CANCEL)) < 0) {
505 		logit("door_create() call failed\n");
506 		syslog(LOG_ERR, gettext(
507 		    "ldap_cachemgr: door_create() call failed"));
508 		perror("door_create");
509 		exit(-1);
510 	}
511 
512 	/*
513 	 * bind to file system
514 	 */
515 
516 	if (stat(LDAP_CACHE_DOOR, &buf) < 0) {
517 		int	newfd;
518 
519 		if ((newfd = creat(LDAP_CACHE_DOOR, 0444)) < 0) {
520 			logit("Cannot create %s:%s\n",
521 			    LDAP_CACHE_DOOR,
522 			    strerror(errno));
523 			exit(1);
524 		}
525 		(void) close(newfd);
526 	}
527 
528 	if (fattach(did, LDAP_CACHE_DOOR) < 0) {
529 		if ((errno != EBUSY) ||
530 		    (fdetach(LDAP_CACHE_DOOR) <  0) ||
531 		    (fattach(did, LDAP_CACHE_DOOR) < 0)) {
532 			logit("fattach() call failed\n");
533 			syslog(LOG_ERR, gettext(
534 			    "ldap_cachemgr: fattach() call failed"));
535 			perror("fattach");
536 			exit(2);
537 		}
538 	}
539 
540 	/* catch SIGHUP revalid signals */
541 	sighupaction.sa_handler = getldap_revalidate;
542 	sighupaction.sa_flags = 0;
543 	(void) sigemptyset(&sighupaction.sa_mask);
544 	(void) sigemptyset(&myset);
545 	(void) sigaddset(&myset, SIGHUP);
546 
547 	if (sigaction(SIGHUP, &sighupaction, NULL) < 0) {
548 		logit("sigaction() call failed\n");
549 		syslog(LOG_ERR,
550 		    gettext("ldap_cachemgr: sigaction() call failed"));
551 		perror("sigaction");
552 		exit(1);
553 	}
554 
555 	if (thr_sigsetmask(SIG_BLOCK, &myset, NULL) < 0) {
556 		logit("thr_sigsetmask() call failed\n");
557 		syslog(LOG_ERR,
558 		    gettext("ldap_cachemgr: thr_sigsetmask() call failed"));
559 		perror("thr_sigsetmask");
560 		exit(1);
561 	}
562 
563 	/*
564 	 *  kick off revalidate threads only if ttl != 0
565 	 */
566 
567 	if (thr_create(NULL, 0, (void *(*)(void*))getldap_refresh,
568 	    NULL, 0, NULL) != 0) {
569 		logit("thr_create() call failed\n");
570 		syslog(LOG_ERR,
571 		    gettext("ldap_cachemgr: thr_create() call failed"));
572 		perror("thr_create");
573 		exit(1);
574 	}
575 
576 	/*
577 	 *  kick off the thread which refreshes the server info
578 	 */
579 
580 	if (thr_create(NULL, 0, (void *(*)(void*))getldap_serverInfo_refresh,
581 	    NULL, 0, NULL) != 0) {
582 		logit("thr_create() call failed\n");
583 		syslog(LOG_ERR,
584 		    gettext("ldap_cachemgr: thr_create() call failed"));
585 		perror("thr_create");
586 		exit(1);
587 	}
588 
589 	/*
590 	 * kick off the thread which cleans up waiting threads for
591 	 * GETSTATUSCHANGE
592 	 */
593 
594 	if (thr_create(NULL, 0, chg_cleanup_waiting_threads,
595 	    NULL, 0, NULL) != 0) {
596 		logit("thr_create() chg_cleanup_waiting_threads call failed\n");
597 		syslog(LOG_ERR,
598 		    gettext("ldap_cachemgr: thr_create() "
599 		    "chg_cleanup_waiting_threads call failed"));
600 		exit(1);
601 	}
602 
603 #ifdef SLP
604 	if (use_slp) {
605 		/* kick off SLP discovery thread */
606 		if (thr_create(NULL, 0, (void *(*)(void *))discover,
607 		    (void *)&refresh, 0, NULL) != 0) {
608 			logit("thr_create() call failed\n");
609 			syslog(LOG_ERR, gettext("ldap_cachemgr: thr_create() "
610 			    "call failed"));
611 			perror("thr_create");
612 			exit(1);
613 		}
614 	}
615 #endif /* SLP */
616 
617 	if (thr_sigsetmask(SIG_UNBLOCK, &myset, NULL) < 0) {
618 		logit("thr_sigsetmask() call failed\n");
619 		syslog(LOG_ERR,
620 		    gettext("ldap_cachemgr: the_sigsetmask() call failed"));
621 		perror("thr_sigsetmask");
622 		exit(1);
623 	}
624 
625 	/*CONSTCOND*/
626 	while (1) {
627 		(void) pause();
628 	}
629 	/* NOTREACHED */
630 	/*LINTED E_FUNC_HAS_NO_RETURN_STMT*/
631 }
632 
633 
634 /*
635  * Before calling the alloca() function we have to be sure that we won't get
636  * beyond the stack. Since we don't know the precise layout of the stack,
637  * the address of an automatic of the function gives us a rough idea, plus/minus
638  * a bit. We also need a bit more of stackspace after the call to be able
639  * to call further functions. Even something as simple as making a system call
640  * from within this function can take ~100 Bytes of stackspace.
641  */
642 #define	SAFETY_BUFFER 32 * 1024 /* 32KB */
643 
644 static
645 size_t
646 get_data_size(LineBuf *config_info, int *err_code)
647 {
648 	size_t		configSize = sizeof (ldap_return_t);
649 	dataunion	*buf = NULL; /* For the 'sizeof' purpose */
650 
651 	if (config_info->str != NULL &&
652 	    config_info->len >= sizeof (buf->data.ldap_ret.ldap_u.config)) {
653 		configSize = sizeof (buf->space) +
654 		    config_info->len -
655 		    sizeof (buf->data.ldap_ret.ldap_u.config);
656 
657 		if (!stack_inbounds((char *)&buf -
658 		    (configSize + SAFETY_BUFFER))) {
659 			/*
660 			 * We do not have enough space on the stack
661 			 * to accomodate the whole DUAProfile
662 			 */
663 			logit("The DUAProfile is too big. There is not enough "
664 			    "space to process it. Ignoring it.\n");
665 			syslog(LOG_ERR, gettext("ldap_cachemgr: The DUAProfile "
666 			    "is too big. There is not enough space "
667 			    "to process it. Ignoring it."));
668 
669 			*err_code = NS_CACHE_SERVERERROR;
670 
671 			free(config_info->str);
672 			config_info->str = NULL;
673 			config_info->len = 0;
674 			configSize = sizeof (ldap_return_t);
675 		}
676 	}
677 
678 	return (configSize);
679 }
680 
681 /*ARGSUSED*/
682 static void
683 switcher(void *cookie, char *argp, size_t arg_size,
684     door_desc_t *dp, uint_t n_desc)
685 {
686 #define	GETSIZE 1000
687 #define	ALLOCATE 1001
688 
689 	ldap_call_t	*ptr = (ldap_call_t *)argp;
690 	ucred_t		*uc = NULL;
691 
692 	LineBuf		configInfo;
693 	dataunion	*buf = NULL;
694 
695 	/*
696 	 * By default the size of  a buffer to be passed down to a client
697 	 * is equal to the size of the ldap_return_t structure. We need
698 	 * a bigger buffer in a few cases.
699 	 */
700 	size_t		configSize = sizeof (ldap_return_t);
701 	int		ldapErrno = 0, state, callnumber;
702 	struct {
703 		void	*begin;
704 		size_t	size;
705 		uint8_t	destroy;
706 	} dataSource;
707 
708 	if (argp == DOOR_UNREF_DATA) {
709 		logit("Door Slam... invalid door param\n");
710 		syslog(LOG_ERR, gettext("ldap_cachemgr: Door Slam... "
711 		    "invalid door param"));
712 		(void) printf(gettext("Door Slam... invalid door param\n"));
713 		exit(0);
714 	}
715 
716 	if (ptr == NULL) { /* empty door call */
717 		(void) door_return(NULL, 0, 0, 0); /* return the favor */
718 	}
719 
720 	bzero(&dataSource, sizeof (dataSource));
721 
722 	/*
723 	 * We presume that sizeof (ldap_return_t) bytes are always available
724 	 * on the stack
725 	 */
726 	callnumber = ptr->ldap_callnumber;
727 
728 	switch (callnumber) {
729 		case NULLCALL:
730 			/*
731 			 * Just a 'ping'. Use the default size
732 			 * of the buffer and set the
733 			 * 'OK' error code.
734 			 */
735 			state = ALLOCATE;
736 			break;
737 		case GETLDAPCONFIG:
738 			/*
739 			 * Get the current LDAP configuration.
740 			 * Since this is dynamic data and its size can exceed
741 			 * the size of ldap_return_t, the next step will
742 			 * calculate who much space exactly is required.
743 			 */
744 			getldap_lookup(&configInfo, ptr);
745 
746 			state = GETSIZE;
747 			break;
748 		case GETLDAPSERVER:
749 			/*
750 			 * Get the root DSE for a next server in the list.
751 			 * Since this is dynamic data and its size can exceed
752 			 * the size of ldap_return_t, the next step will
753 			 * calculate who much space exactly is required.
754 			 */
755 			getldap_getserver(&configInfo, ptr);
756 
757 			state = GETSIZE;
758 			break;
759 		case GETCACHESTAT:
760 			/*
761 			 * Get the cache stattistics.
762 			 * Since this is dynamic data and its size can exceed
763 			 * the size of ldap_return_t, the next step will
764 			 * calculate how much space exactly is required.
765 			 */
766 			getldap_get_cacheStat(&configInfo);
767 
768 			state = GETSIZE;
769 			break;
770 		case GETADMIN:
771 			/*
772 			 * Get current configuration and statistics.
773 			 * The size of the statistics structure is less then
774 			 * sizeof (ldap_return_t). So specify the source
775 			 * where to take the info and proceed with the memory
776 			 * allocation.
777 			 */
778 			state = ALLOCATE;
779 
780 			if (ldapErrno == 0) {
781 				dataSource.begin = &current_admin;
782 				dataSource.size = sizeof (current_admin);
783 				dataSource.destroy = 0;
784 			}
785 			break;
786 		case KILLSERVER:
787 			/*
788 			 * Process the request and proceed with the default
789 			 * buffer allocation.
790 			 */
791 			if (is_root(1, "KILLSERVER", &uc))
792 				exit(0);
793 
794 			ldapErrno = -1;
795 			state = ALLOCATE;
796 			break;
797 		case SETADMIN:
798 			/*
799 			 * Process the request and proceed with the default
800 			 * buffer allocation.
801 			 */
802 			if (is_root(1, "SETADMIN", &uc))
803 				ldapErrno = setadmin(ptr);
804 			else
805 				ldapErrno = -1;
806 
807 			state = ALLOCATE;
808 			break;
809 		case GETCACHE:
810 			/*
811 			 * Get the cache stattistics.
812 			 * Since this is dynamic data and its size can exceed
813 			 * the size of ldap_return_t, the next step will
814 			 * calculate how much space exactly is required.
815 			 */
816 			getldap_get_cacheData(&configInfo, ptr);
817 
818 			state = GETSIZE;
819 			break;
820 		case SETCACHE:
821 			/*
822 			 * Process the request and proceed with the default
823 			 * buffer allocation.
824 			 */
825 			if (is_root(0, "SETCACHE", &uc) &&
826 			    is_called_from_nscd(ucred_getpid(uc))) {
827 				ldapErrno = getldap_set_cacheData(ptr);
828 				current_admin.ldap_stat.ldap_numbercalls++;
829 			} else
830 				ldapErrno = -1;
831 
832 			if (uc != NULL)
833 				ucred_free(uc);
834 			state = ALLOCATE;
835 			break;
836 		case GETSTATUSCHANGE:
837 			/*
838 			 * Process the request and proceed with the default
839 			 * buffer allocation.
840 			 */
841 			(void) mutex_lock(&chg_threads_num_lock);
842 			chg_threads_num++;
843 			if (chg_threads_num > MAX_CHG_THREADS) {
844 				chg_threads_num--;
845 				(void) mutex_unlock(&chg_threads_num_lock);
846 				ldapErrno = CHG_EXCEED_MAX_THREADS;
847 				state = ALLOCATE;
848 				break;
849 			}
850 			(void) mutex_unlock(&chg_threads_num_lock);
851 
852 			if (is_root(0, "GETSTATUSCHANGE", &uc) &&
853 			    is_called_from_nscd(ucred_getpid(uc))) {
854 				ldapErrno = chg_get_statusChange(
855 				    &configInfo, ptr, ucred_getpid(uc));
856 				state = GETSIZE;
857 			} else {
858 				ldapErrno = -1;
859 				state = ALLOCATE;
860 			}
861 			if (uc != NULL)
862 				ucred_free(uc);
863 
864 			(void) mutex_lock(&chg_threads_num_lock);
865 			chg_threads_num--;
866 			(void) mutex_unlock(&chg_threads_num_lock);
867 			break;
868 		default:
869 			/*
870 			 * This means an unknown request type. Proceed with
871 			 * the default buffer allocation.
872 			 */
873 			logit("Unknown ldap service door call op %d\n",
874 			    ptr->ldap_callnumber);
875 			ldapErrno = -99;
876 
877 			state = ALLOCATE;
878 			break;
879 	}
880 
881 	switch (state) {
882 		case GETSIZE:
883 			/*
884 			 * This stage calculates how much data will be
885 			 * passed down to the client, checks if there is
886 			 * enough space on the stack to accommodate the data,
887 			 * increases the value of the configSize variable
888 			 * if necessary and specifies the data source.
889 			 * In case of any error occurred ldapErrno will be set
890 			 * appropriately.
891 			 */
892 			if (configInfo.str == NULL) {
893 				ldapErrno = -1;
894 			}
895 
896 			configSize = get_data_size(&configInfo, &ldapErrno);
897 
898 			if (ldapErrno == 0) {
899 				dataSource.begin = configInfo.str;
900 				dataSource.size = configInfo.len;
901 				dataSource.destroy = 1;
902 			}
903 
904 			current_admin.ldap_stat.ldap_numbercalls++;
905 			/* FALLTHRU */
906 		case ALLOCATE:
907 			/*
908 			 * Allocate a buffer of the calculated (or default) size
909 			 * and proceed with populating it with data.
910 			 */
911 			buf = (dataunion *) alloca(configSize);
912 
913 			/*
914 			 * Set a return code and, if a data source is specified,
915 			 * copy data from the source to the buffer.
916 			 */
917 			buf->data.ldap_ret.ldap_errno = ldapErrno;
918 			buf->data.ldap_ret.ldap_return_code = ldapErrno;
919 			buf->data.ldap_ret.ldap_bufferbytesused = configSize;
920 
921 			if (dataSource.begin != NULL) {
922 				(void) memcpy(buf->data.ldap_ret.ldap_u.config,
923 				    dataSource.begin,
924 				    dataSource.size);
925 				if (dataSource.destroy) {
926 					free(dataSource.begin);
927 				}
928 			}
929 
930 	}
931 	(void) door_return((char *)&buf->data,
932 	    buf->data.ldap_ret.ldap_bufferbytesused,
933 	    NULL,
934 	    0);
935 #undef	GETSIZE
936 #undef	ALLOCATE
937 }
938 
939 static void
940 usage(char *s)
941 {
942 	(void) fprintf(stderr,
943 	    gettext("Usage: %s [-d debug_level] [-l logfilename]\n"), s);
944 	(void) fprintf(stderr, gettext("	[-K] "
945 	    "[-r revalidate_interval] "));
946 #ifndef SLP
947 	(void) fprintf(stderr, gettext("	[-g]\n"));
948 #else
949 	(void) fprintf(stderr, gettext("	[-g] [-s]\n"));
950 #endif /* SLP */
951 	exit(1);
952 }
953 
954 
955 static int	logfd = -1;
956 
957 static int
958 cachemgr_set_lf(admin_t *ptr, char *logfile)
959 {
960 	int	newlogfd;
961 
962 	/*
963 	 *  we don't really want to try and open the log file
964 	 *  /dev/null since that will fail w/ our security fixes
965 	 */
966 
967 	if (logfile == NULL || *logfile == 0) {
968 		/*EMPTY*/;
969 	} else if (strcmp(logfile, "/dev/null") == 0) {
970 		(void) strcpy(current_admin.logfile, "/dev/null");
971 		(void) close(logfd);
972 		logfd = -1;
973 	} else {
974 		if ((newlogfd =
975 		    open(logfile, O_EXCL|O_WRONLY|O_CREAT, 0644)) < 0) {
976 			/*
977 			 * File already exists... now we need to get cute
978 			 * since opening a file in a world-writeable directory
979 			 * safely is hard = it could be a hard link or a
980 			 * symbolic link to a system file.
981 			 *
982 			 */
983 			struct stat	before;
984 
985 			if (lstat(logfile, &before) < 0) {
986 				logit("Cannot open new logfile \"%s\": %sn",
987 				    logfile, strerror(errno));
988 				return (-1);
989 			}
990 			if (S_ISREG(before.st_mode) &&	/* no symbolic links */
991 			    (before.st_nlink == 1) &&	/* no hard links */
992 			    (before.st_uid == 0)) {	/* owned by root */
993 				if ((newlogfd =
994 				    open(logfile,
995 				    O_APPEND|O_WRONLY, 0644)) < 0) {
996 					logit("Cannot open new logfile "
997 					    "\"%s\": %s\n",
998 					    logfile, strerror(errno));
999 					return (-1);
1000 				}
1001 			} else {
1002 				logit("Cannot use specified logfile "
1003 				    "\"%s\": file is/has links or isn't "
1004 				    "owned by root\n", logfile);
1005 				return (-1);
1006 			}
1007 		}
1008 		(void) strlcpy(ptr->logfile, logfile, sizeof (ptr->logfile));
1009 		(void) close(logfd);
1010 		logfd = newlogfd;
1011 		logit("Starting ldap_cachemgr, logfile %s\n", logfile);
1012 	}
1013 	return (0);
1014 }
1015 
1016 /*PRINTFLIKE1*/
1017 void
1018 logit(char *format, ...)
1019 {
1020 	static mutex_t	loglock;
1021 	struct timeval	tv;
1022 	char		buffer[BUFSIZ];
1023 	va_list		ap;
1024 
1025 	va_start(ap, format);
1026 
1027 	if (logfd >= 0) {
1028 		int	safechars;
1029 
1030 		(void) gettimeofday(&tv, NULL);
1031 		(void) ctime_r(&tv.tv_sec, buffer, BUFSIZ);
1032 		(void) snprintf(buffer+19, BUFSIZE, ".%.4ld	",
1033 		    tv.tv_usec/100);
1034 		safechars = sizeof (buffer) - 30;
1035 		if (vsnprintf(buffer+25, safechars, format, ap) > safechars)
1036 			(void) strcat(buffer, "...\n");
1037 		(void) mutex_lock(&loglock);
1038 		(void) write(logfd, buffer, strlen(buffer));
1039 		(void) mutex_unlock(&loglock);
1040 	}
1041 	va_end(ap);
1042 }
1043 
1044 
1045 static int
1046 client_getadmin(admin_t *ptr)
1047 {
1048 	dataunion		u;
1049 	ldap_data_t	*dptr;
1050 	int		ndata;
1051 	int		adata;
1052 
1053 	u.data.ldap_call.ldap_callnumber = GETADMIN;
1054 	ndata = sizeof (u);
1055 	adata = sizeof (u.data);
1056 	dptr = &u.data;
1057 
1058 	if (__ns_ldap_trydoorcall(&dptr, &ndata, &adata) != NS_CACHE_SUCCESS) {
1059 		return (-1);
1060 	}
1061 	(void) memcpy(ptr, dptr->ldap_ret.ldap_u.buff, sizeof (*ptr));
1062 
1063 	return (0);
1064 }
1065 
1066 
1067 static int
1068 setadmin(ldap_call_t *ptr)
1069 {
1070 	admin_t	*new;
1071 
1072 	new = (admin_t *)ptr->ldap_u.domainname;
1073 
1074 	/*
1075 	 *  global admin stuff
1076 	 */
1077 
1078 	if ((cachemgr_set_lf(&current_admin, new->logfile) < 0) ||
1079 	    cachemgr_set_dl(&current_admin, new->debug_level) < 0) {
1080 		return (-1);
1081 	}
1082 
1083 	if (cachemgr_set_ttl(&current_admin.ldap_stat,
1084 	    "ldap",
1085 	    new->ldap_stat.ldap_ttl) < 0) {
1086 		return (-1);
1087 	}
1088 
1089 	return (0);
1090 }
1091 
1092 
1093 static void
1094 client_killserver()
1095 {
1096 	dataunion		u;
1097 	ldap_data_t		*dptr;
1098 	int			ndata;
1099 	int			adata;
1100 
1101 	u.data.ldap_call.ldap_callnumber = KILLSERVER;
1102 	ndata = sizeof (u);
1103 	adata = sizeof (ldap_call_t);
1104 	dptr = &u.data;
1105 
1106 	__ns_ldap_trydoorcall(&dptr, &ndata, &adata);
1107 }
1108 
1109 
1110 static int
1111 client_setadmin(admin_t *ptr)
1112 {
1113 	dataunion		u;
1114 	ldap_data_t		*dptr;
1115 	int			ndata;
1116 	int			adata;
1117 
1118 	u.data.ldap_call.ldap_callnumber = SETADMIN;
1119 	(void) memcpy(u.data.ldap_call.ldap_u.domainname, ptr, sizeof (*ptr));
1120 	ndata = sizeof (u);
1121 	adata = sizeof (*ptr);
1122 	dptr = &u.data;
1123 
1124 	if (__ns_ldap_trydoorcall(&dptr, &ndata, &adata) != NS_CACHE_SUCCESS) {
1125 		return (-1);
1126 	}
1127 
1128 	return (0);
1129 }
1130 
1131 static int
1132 client_showstats(admin_t *ptr)
1133 {
1134 	dataunion	u;
1135 	ldap_data_t	*dptr;
1136 	int		ndata;
1137 	int		adata;
1138 	char		*rbuf, *sptr, *rest;
1139 
1140 	/*
1141 	 * print admin data
1142 	 */
1143 	(void) printf(gettext("\ncachemgr configuration:\n"));
1144 	(void) printf(gettext("server debug level %10d\n"), ptr->debug_level);
1145 	(void) printf(gettext("server log file\t\"%s\"\n"), ptr->logfile);
1146 	(void) printf(gettext("number of calls to ldapcachemgr %10d\n"),
1147 	    ptr->ldap_stat.ldap_numbercalls);
1148 
1149 	/*
1150 	 * get cache data statistics
1151 	 */
1152 	u.data.ldap_call.ldap_callnumber = GETCACHESTAT;
1153 	ndata = sizeof (u);
1154 	adata = sizeof (ldap_call_t);
1155 	dptr = &u.data;
1156 
1157 	if (__ns_ldap_trydoorcall(&dptr, &ndata, &adata) != NS_CACHE_SUCCESS) {
1158 		(void) printf(
1159 		    gettext("\nCache data statistics not available!\n"));
1160 		return (0);
1161 	}
1162 
1163 	/*
1164 	 * print cache data statistics line by line
1165 	 */
1166 	(void) printf(gettext("\ncachemgr cache data statistics:\n"));
1167 	rbuf = dptr->ldap_ret.ldap_u.buff;
1168 	sptr = strtok_r(rbuf, DOORLINESEP, &rest);
1169 	for (;;) {
1170 		(void) printf("%s\n", sptr);
1171 		sptr = strtok_r(NULL, DOORLINESEP, &rest);
1172 		if (sptr == NULL)
1173 			break;
1174 	}
1175 	return (0);
1176 }
1177 
1178 
1179 /*
1180  * detach from tty
1181  */
1182 static void
1183 detachfromtty(char *pgm)
1184 {
1185 	int 	status;
1186 	pid_t	pid, wret;
1187 
1188 	(void) close(0);
1189 	(void) close(1);
1190 	/*
1191 	 * Block the SIGUSR1 signal
1192 	 * just in case that the child
1193 	 * process may run faster than
1194 	 * the parent process and
1195 	 * send this signal before
1196 	 * the signal handler is ready
1197 	 * in the parent process.
1198 	 * This error will cause the parent
1199 	 * to exit with the User Signal 1
1200 	 * exit code (144).
1201 	 */
1202 	(void) sighold(SIGUSR1);
1203 	pid = fork1();
1204 	switch (pid) {
1205 		case (pid_t)-1:
1206 			logit("detachfromtty(): fork1() call failed\n");
1207 			(void) fprintf(stderr,
1208 			    gettext("%s: fork1() call failed.\n"),
1209 			    pgm);
1210 			syslog(LOG_ERR,
1211 			    gettext("ldap_cachemgr: fork1() call failed."));
1212 			exit(1);
1213 			break;
1214 		case 0:
1215 			/*
1216 			 * child process does not
1217 			 * need to worry about
1218 			 * the SIGUSR1 signal
1219 			 */
1220 			(void) sigrelse(SIGUSR1);
1221 			(void) close(2);
1222 			break;
1223 		default:
1224 			/*
1225 			 * Wait forever until the child process
1226 			 * has exited, or has signalled that at
1227 			 * least one server in the server list
1228 			 * is up.
1229 			 */
1230 			if (signal(SIGUSR1, sig_ok_to_exit) == SIG_ERR) {
1231 				logit("detachfromtty(): "
1232 				    "can't set up signal handler to "
1233 				    " catch SIGUSR1.\n");
1234 				(void) fprintf(stderr,
1235 				    gettext("%s: signal() call failed.\n"),
1236 				    pgm);
1237 				syslog(LOG_ERR, gettext("ldap_cachemgr: "
1238 				    "can't set up signal handler to "
1239 				    " catch SIGUSR1."));
1240 				exit(1);
1241 			}
1242 
1243 			/*
1244 			 * now unblock the SIGUSR1 signal
1245 			 * to handle the pending or
1246 			 * soon to arrive SIGUSR1 signal
1247 			 */
1248 			(void) sigrelse(SIGUSR1);
1249 			wret = waitpid(pid, &status, 0);
1250 
1251 			if (wret == -1) {
1252 				logit("detachfromtty(): "
1253 				    "waitpid() call failed\n");
1254 				(void) fprintf(stderr,
1255 				    gettext("%s: waitpid() call failed.\n"),
1256 				    pgm);
1257 				syslog(LOG_ERR,
1258 				    gettext("ldap_cachemgr: waitpid() "
1259 				    "call failed."));
1260 				exit(1);
1261 			}
1262 			if (wret != pid) {
1263 				logit("detachfromtty(): "
1264 				    "waitpid() returned %ld when "
1265 				    "child pid was %ld\n",
1266 				    wret, pid);
1267 				(void) fprintf(stderr,
1268 				    gettext(
1269 				    "%s: waitpid() returned %ld when "
1270 				    "child pid was %ld.\n"),
1271 				    pgm, wret, pid);
1272 				syslog(LOG_ERR,
1273 				    gettext("ldap_cachemgr: waitpid() "
1274 				    "returned different "
1275 				    "child pid."));
1276 				exit(1);
1277 			}
1278 
1279 			/* evaluate return status */
1280 			if (WIFEXITED(status)) {
1281 				if (WEXITSTATUS(status) == 0) {
1282 					exit(0);
1283 				}
1284 				logit("detachfromtty(): "
1285 				    "child failed (rc = %d).\n",
1286 				    WEXITSTATUS(status));
1287 				(void) fprintf(stderr,
1288 				    gettext("%s: failed. Please see "
1289 				    "syslog for details.\n"),
1290 				    pgm);
1291 				syslog(LOG_ERR,
1292 				    gettext("ldap_cachemgr: failed "
1293 				    "(rc = %d)."),
1294 				    WEXITSTATUS(status));
1295 			} else if (WIFSIGNALED(status)) {
1296 				logit("detachfromtty(): "
1297 				    "child terminated by signal %d.\n",
1298 				    WTERMSIG(status));
1299 				(void) fprintf(stderr,
1300 				gettext("%s: terminated by signal %d.\n"),
1301 				    pgm, WTERMSIG(status));
1302 				syslog(LOG_ERR,
1303 				    gettext("ldap_cachemgr: terminated by "
1304 				    "signal %d.\n"),
1305 				    WTERMSIG(status));
1306 			} else if (WCOREDUMP(status)) {
1307 				logit("detachfromtty(): child core dumped.\n"),
1308 				    (void) fprintf(stderr,
1309 				    gettext("%s: core dumped.\n"),
1310 				    pgm);
1311 				syslog(LOG_ERR,
1312 				    gettext("ldap_cachemgr: "
1313 				    "core dumped.\n"));
1314 			}
1315 
1316 			exit(1);
1317 	}
1318 	(void) setsid();
1319 	if (open("/dev/null", O_RDWR, 0) != -1) {
1320 		(void) dup(0);
1321 		(void) dup(0);
1322 	}
1323 }
1324 
1325 /*
1326  * Check if the door client's euid is 0
1327  *
1328  * We could check for some privilege or re-design the interfaces that
1329  * lead to is_root() being called so that we rely on SMF and RBAC, but
1330  * we need this check only for dealing with undocumented-but-possibly-
1331  * used interfaces.  Anything beyond checking for euid == 0 here would
1332  * be overkill considering that those are undocumented interfaces.
1333  *
1334  * If free_uc is 0, the caller is responsible for freeing *ucp.
1335  *
1336  * return - 0 euid != 0
1337  *          1 euid == 0
1338  */
1339 static int
1340 is_root(int free_uc, char *dc_str, ucred_t **ucp)
1341 {
1342 	int	rc;
1343 
1344 	if (door_ucred(ucp) != 0) {
1345 		rc = errno;
1346 		logit("door_ucred() call failed %s\n", strerror(rc));
1347 		syslog(LOG_ERR, gettext("ldap_cachemgr: door_ucred() call %s "
1348 		    "failed %s"), strerror(rc));
1349 		return (0);
1350 	}
1351 
1352 
1353 	if (ucred_geteuid(*ucp) != 0) {
1354 
1355 		if (current_admin.debug_level >= DBG_CANT_FIND)
1356 			logit("%s call failed(cred): caller pid %ld, uid %u, "
1357 			    "euid %u\n", dc_str, ucred_getpid(*ucp),
1358 			    ucred_getruid(*ucp), ucred_geteuid(*ucp));
1359 
1360 		rc = 0;
1361 	} else {
1362 
1363 		if (current_admin.debug_level >= DBG_ALL)
1364 			logit("ldap_cachemgr received %s call from pid %ld, "
1365 			    "uid %u, euid %u\n", dc_str, ucred_getpid(*ucp),
1366 			    ucred_getruid(*ucp), ucred_geteuid(*ucp));
1367 		rc = 1;
1368 	}
1369 
1370 	if (free_uc)
1371 		ucred_free(*ucp);
1372 
1373 	return (rc);
1374 }
1375 
1376 /*
1377  * Check if pid is nscd
1378  *
1379  * Input: pid - process id of the door client that calls ldap_cachemgr
1380  *
1381  * Return: 0 - No
1382  *         1 - Yes
1383  */
1384 
1385 int
1386 is_called_from_nscd(pid_t pid)
1387 
1388 {
1389 	static mutex_t	_door_lock = DEFAULTMUTEX;
1390 	static	int	doorfd = -1;
1391 	int		match;
1392 	door_info_t 	my_door;
1393 
1394 	/*
1395 	 * the first time in we try and open and validate the door.
1396 	 * the validations are that the door must have been
1397 	 * created with the door cookie and
1398 	 * that the file attached to the door is owned by root
1399 	 * and readonly by user, group and other.  If any of these
1400 	 * validations fail we refuse to use the door.
1401 	 */
1402 
1403 	(void) mutex_lock(&_door_lock);
1404 
1405 try_again:
1406 
1407 	if (doorfd == -1) {
1408 
1409 		if ((doorfd = open(NAME_SERVICE_DOOR, O_RDONLY, 0))
1410 		    == -1) {
1411 			(void) mutex_unlock(&_door_lock);
1412 			return (0);
1413 		}
1414 
1415 		if (door_info(doorfd, &my_door) == -1 ||
1416 		    (my_door.di_attributes & DOOR_REVOKED) ||
1417 		    my_door.di_data != (uintptr_t)NAME_SERVICE_DOOR_COOKIE) {
1418 			/*
1419 			 * we should close doorfd because we just opened it
1420 			 */
1421 			(void) close(doorfd);
1422 			doorfd = -1;
1423 			(void) mutex_unlock(&_door_lock);
1424 			return (0);
1425 		}
1426 	} else {
1427 		/*
1428 		 * doorfd is cached. Double check just in case
1429 		 * the door server is restarted or is down.
1430 		 */
1431 		if (door_info(doorfd, &my_door) == -1 ||
1432 		    my_door.di_data != (uintptr_t)NAME_SERVICE_DOOR_COOKIE) {
1433 			/*
1434 			 * don't close it -
1435 			 * someone else has clobbered fd
1436 			 */
1437 			doorfd = -1;
1438 			goto try_again;
1439 		}
1440 
1441 		if (my_door.di_attributes & DOOR_REVOKED) {
1442 			(void) close(doorfd);
1443 			doorfd = -1;	/* try and restart connection */
1444 			goto try_again;
1445 		}
1446 	}
1447 
1448 	/*
1449 	 * door descriptor exists and is valid
1450 	 */
1451 	if (pid == my_door.di_target)
1452 		match = 1;
1453 	else
1454 		match = 0;
1455 
1456 	(void) mutex_unlock(&_door_lock);
1457 
1458 	return (match);
1459 
1460 }
1461