xref: /titanic_41/usr/src/lib/libadutils/common/addisc.c (revision ebe15f48e9897d68d978938414a5c16cb0ceb049)
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 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Active Directory Auto-Discovery.
29  *
30  * This [project private] API allows the caller to provide whatever
31  * details it knows a priori (i.e., provided via configuration so as to
32  * override auto-discovery) and in any order.  Then the caller can ask
33  * for any of the auto-discoverable parameters in any order.
34  *
35  * But there is an actual order in which discovery must be done.  Given
36  * the discovery mechanism implemented here, that order is:
37  *
38  *  - the domain name joined must be discovered first
39  *  - then the domain controllers
40  *  - then the forest name and site name
41  *  - then the global catalog servers, and site-specific domain
42  *    controllers and global catalog servers.
43  *
44  * The API does not require it be called in the same order because there
45  * may be other discovery mechanisms in the future, and exposing
46  * ordering requirements of the current mechanism now can create trouble
47  * down the line.  Also, this makes the API easier to use now, which
48  * means less work to do some day when we make this a public API.
49  *
50  * Domain discovery is done by res_nsearch() of the DNS SRV RR name for
51  * domain controllers.  As long as the joined domain appears in the DNS
52  * resolver's search list then we'll find it.
53  *
54  * Domain controller discovery is a matter of formatting the DNS SRV RR
55  * FQDN for domain controllers and doing a lookup for them.  Knowledge
56  * of the domain name is not fundamentally required, but we separate the
57  * two processes, which in practice can lead to one more DNS lookup than
58  * is strictly required.
59  *
60  * Forest and site name discovery require an LDAP search of the AD
61  * "configuration partition" at a domain controller for the joined
62  * domain.  Forest and site name discovery depend on knowing the joined
63  * domain name and domain controllers for that domain.
64  *
65  * Global catalog server discovery requires knowledge of the forest
66  * name in order to format the DNS SRV RR FQDN to lookup.  Site-specific
67  * domain controller discovery depends on knowing the site name (and,
68  * therefore, joined domain, ...).  Site-specific global catalog server
69  * discovery depends on knowledge of the forest and site names, which
70  * depend on...
71  *
72  * All the work of discovering particular items is done by functions
73  * named validate_<item>().  Each such function calls validate_<item>()
74  * for any items that it depends on.
75  *
76  * This API is not thread-safe.
77  */
78 
79 
80 #include <stdio.h>
81 #include <string.h>
82 #include <strings.h>
83 #include <unistd.h>
84 #include <assert.h>
85 #include <stdlib.h>
86 #include <net/if.h>
87 #include <net/if.h>
88 #include <sys/types.h>
89 #include <sys/socket.h>
90 #include <sys/sockio.h>
91 #include <netinet/in.h>
92 #include <netinet/in.h>
93 #include <arpa/inet.h>
94 #include <arpa/nameser.h>
95 #include <resolv.h>
96 #include <netdb.h>
97 #include <ctype.h>
98 #include <errno.h>
99 #include <ldap.h>
100 #include <sasl/sasl.h>
101 #include <sys/u8_textprep.h>
102 #include <syslog.h>
103 #include "adutils_impl.h"
104 #include "addisc.h"
105 
106 
107 enum ad_item_state {
108 		AD_STATE_INVALID = 0,	/* The value is not valid */
109 		AD_STATE_FIXED,		/* The value was fixed by caller */
110 		AD_STATE_AUTO		/* The value is auto discovered */
111 		};
112 
113 enum ad_data_type {
114 		AD_STRING = 123,
115 		AD_DIRECTORY,
116 		AD_DOMAINS_IN_FOREST,
117 		AD_TRUSTED_DOMAINS
118 		};
119 
120 
121 typedef struct ad_subnet {
122 	char subnet[24];
123 } ad_subnet_t;
124 
125 
126 typedef struct ad_item {
127 	enum ad_item_state	state;
128 	enum ad_data_type	type;
129 	void 			*value;
130 	time_t 			ttl;
131 	unsigned int 		version;	/* Version is only changed */
132 						/* if the value changes */
133 #define	PARAM1		0
134 #define	PARAM2		1
135 	int 		param_version[2];
136 					/* These holds the version of */
137 					/* dependents so that a dependent */
138 					/* change can be detected */
139 } ad_item_t;
140 
141 typedef struct ad_disc {
142 	struct __res_state res_state;
143 	int		res_ninitted;
144 	ad_subnet_t	*subnets;
145 	boolean_t	subnets_changed;
146 	time_t		subnets_last_check;
147 	ad_item_t	domain_name;		/* DNS hostname string */
148 	ad_item_t	domain_controller;	/* Directory hostname and */
149 						/* port array */
150 	ad_item_t	site_name;		/* String */
151 	ad_item_t	forest_name;		/* DNS forestname string */
152 	ad_item_t	global_catalog;		/* Directory hostname and */
153 						/* port array */
154 	ad_item_t	domains_in_forest;	/* DNS domainname and SID */
155 						/* array */
156 	ad_item_t	trusted_domains;	/* DNS domainname and trust */
157 						/* direction array */
158 	/* Site specfic versions */
159 	ad_item_t	site_domain_controller;	/* Directory hostname and */
160 						/* port array */
161 	ad_item_t	site_global_catalog;	/* Directory hostname and */
162 						/* port array */
163 } ad_disc;
164 
165 
166 #define	DNS_MAX_NAME	NS_MAXDNAME
167 
168 
169 /* SRV RR names for various queries */
170 #define	LDAP_SRV_HEAD		"_ldap._tcp."
171 #define	SITE_SRV_MIDDLE		"%s._sites."
172 #define	GC_SRV_TAIL		"gc._msdcs"
173 #define	DC_SRV_TAIL		"dc._msdcs"
174 #define	ALL_GC_SRV_TAIL		"_gc._tcp"
175 #define	PDC_SRV			 "_ldap._tcp.pdc._msdcs.%s"
176 
177 /* A RR name for all GCs -- last resort this works */
178 #define	GC_ALL_A_NAME_FSTR "gc._msdcs.%s."
179 
180 
181 /*
182  * We try res_ninit() whenever we don't have one.  res_ninit() fails if
183  * idmapd is running before the network is up!
184  */
185 #define	DO_RES_NINIT(ctx)   if (!(ctx)->res_ninitted) \
186 		(ctx)->res_ninitted = (res_ninit(&ctx->res_state) != -1)
187 
188 #define	is_fixed(item)					\
189 	((item)->state == AD_STATE_FIXED)
190 
191 #define	is_changed(item, num, param) 			\
192 	((item)->param_version[num] != (param)->version)
193 
194 /*LINTLIBRARY*/
195 
196 /*
197  * Function definitions
198  */
199 static ad_item_t *
200 validate_SiteName(ad_disc_t ctx);
201 
202 
203 
204 static void
205 update_version(ad_item_t *item, int  num, ad_item_t *param)
206 {
207 	item->param_version[num] = param->version;
208 }
209 
210 
211 
212 static boolean_t
213 is_valid(ad_item_t *item)
214 {
215 	if (item->value != NULL) {
216 		if (item->state == AD_STATE_FIXED)
217 			return (B_TRUE);
218 		if (item->state == AD_STATE_AUTO &&
219 		    (item->ttl == 0 || item->ttl > time(NULL)))
220 			return (B_TRUE);
221 	}
222 	return (B_FALSE);
223 }
224 
225 
226 static void
227 update_item(ad_item_t *item, void *value, enum ad_item_state state,
228 		uint32_t ttl)
229 {
230 	if (item->value != NULL && value != NULL) {
231 		if ((item->type == AD_STRING &&
232 		    strcmp(item->value, value) != 0) ||
233 		    (item->type == AD_DIRECTORY &&
234 		    ad_disc_compare_ds(item->value, value) != 0)||
235 		    (item->type == AD_DOMAINS_IN_FOREST &&
236 		    ad_disc_compare_domainsinforest(item->value, value) != 0) ||
237 		    (item->type == AD_TRUSTED_DOMAINS &&
238 		    ad_disc_compare_trusteddomains(item->value, value) != 0))
239 			item->version++;
240 	} else if (item->value != value)
241 		item->version++;
242 
243 	if (item->value != NULL)
244 		free(item->value);
245 
246 	item->value = value;
247 	item->state = state;
248 
249 	if (ttl == 0)
250 		item->ttl = 0;
251 	else
252 		item->ttl = time(NULL) + ttl;
253 }
254 
255 
256 /* Compare DS lists */
257 int
258 ad_disc_compare_ds(idmap_ad_disc_ds_t *ds1, idmap_ad_disc_ds_t *ds2)
259 {
260 	int		i, j;
261 	int		num_ds1;
262 	int		num_ds2;
263 	boolean_t	match;
264 
265 	for (i = 0; ds1[i].host[0] != '\0'; i++)
266 		continue;
267 	num_ds1 = i;
268 	for (j = 0; ds2[j].host[0] != '\0'; j++)
269 		continue;
270 	num_ds2 = j;
271 	if (num_ds1 != num_ds2)
272 		return (1);
273 
274 	for (i = 0; i < num_ds1; i++) {
275 		match = B_FALSE;
276 		for (j = 0; j < num_ds2; j++) {
277 			if (strcmp(ds1[i].host, ds2[j].host) == 0 &&
278 			    ds1[i].port == ds2[j].port) {
279 				match = B_TRUE;
280 				break;
281 			}
282 		}
283 		if (!match)
284 			return (1);
285 	}
286 	return (0);
287 }
288 
289 
290 /* Copy a list of DSs */
291 static idmap_ad_disc_ds_t *
292 ds_dup(const idmap_ad_disc_ds_t *srv)
293 {
294 	int	i;
295 	int	size;
296 	idmap_ad_disc_ds_t *new = NULL;
297 
298 	for (i = 0; srv[i].host[0] != '\0'; i++)
299 		continue;
300 
301 	size = (i + 1) * sizeof (idmap_ad_disc_ds_t);
302 	new = malloc(size);
303 	if (new != NULL)
304 		memcpy(new, srv, size);
305 	return (new);
306 }
307 
308 
309 int
310 ad_disc_compare_trusteddomains(ad_disc_trusteddomains_t *td1,
311 			ad_disc_trusteddomains_t *td2)
312 {
313 	int		i, j;
314 	int		num_td1;
315 	int		num_td2;
316 	boolean_t	match;
317 
318 	for (i = 0; td1[i].domain[0] != '\0'; i++)
319 		continue;
320 	num_td1 = i;
321 
322 	for (j = 0; td2[j].domain[0] != '\0'; j++)
323 		continue;
324 	num_td2 = j;
325 
326 	if (num_td1 != num_td2)
327 		return (1);
328 
329 	for (i = 0; i < num_td1; i++) {
330 		match = B_FALSE;
331 		for (j = 0; j < num_td2; j++) {
332 			if (domain_eq(td1[i].domain, td2[j].domain)) {
333 				match = B_TRUE;
334 				break;
335 			}
336 		}
337 		if (!match)
338 			return (1);
339 	}
340 	return (0);
341 }
342 
343 
344 
345 /* Copy a list of Trusted Domains */
346 static ad_disc_trusteddomains_t *
347 td_dup(const ad_disc_trusteddomains_t *td)
348 {
349 	int	i;
350 	int	size;
351 	ad_disc_trusteddomains_t *new = NULL;
352 
353 	for (i = 0; td[i].domain[0] != '\0'; i++)
354 		continue;
355 
356 	size = (i + 1) * sizeof (ad_disc_trusteddomains_t);
357 	new = malloc(size);
358 	if (new != NULL)
359 		memcpy(new, td, size);
360 	return (new);
361 }
362 
363 
364 
365 int
366 ad_disc_compare_domainsinforest(ad_disc_domainsinforest_t *df1,
367 			ad_disc_domainsinforest_t *df2)
368 {
369 	int		i, j;
370 	int		num_df1;
371 	int		num_df2;
372 	boolean_t	match;
373 
374 	for (i = 0; df1[i].domain[0] != '\0'; i++)
375 		continue;
376 	num_df1 = i;
377 
378 	for (j = 0; df2[j].domain[0] != '\0'; j++)
379 		continue;
380 	num_df2 = j;
381 
382 	if (num_df1 != num_df2)
383 		return (1);
384 
385 	for (i = 0; i < num_df1; i++) {
386 		match = B_FALSE;
387 		for (j = 0; j < num_df2; j++) {
388 			if (domain_eq(df1[i].domain, df2[j].domain) &&
389 			    strcmp(df1[i].sid, df2[j].sid) == 0) {
390 				match = B_TRUE;
391 				break;
392 			}
393 		}
394 		if (!match)
395 			return (1);
396 	}
397 	return (0);
398 }
399 
400 
401 
402 /* Copy a list of Trusted Domains */
403 static ad_disc_domainsinforest_t *
404 df_dup(const ad_disc_domainsinforest_t *df)
405 {
406 	int	i;
407 	int	size;
408 	ad_disc_domainsinforest_t *new = NULL;
409 
410 	for (i = 0; df[i].domain[0] != '\0'; i++)
411 		continue;
412 
413 	size = (i + 1) * sizeof (ad_disc_domainsinforest_t);
414 	new = malloc(size);
415 	if (new != NULL)
416 		memcpy(new, df, size);
417 	return (new);
418 }
419 
420 
421 
422 
423 
424 /*
425  * Returns an array of IPv4 address/prefix length
426  * The last subnet is NULL
427  */
428 static ad_subnet_t *
429 find_subnets()
430 {
431 	int		sock, n, i;
432 	struct lifconf	lifc;
433 	struct lifreq	lifr, *lifrp;
434 	struct lifnum	lifn;
435 	uint32_t	prefix_len;
436 	char		*s;
437 	ad_subnet_t	*results;
438 
439 	lifrp = &lifr;
440 
441 	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
442 		logger(LOG_ERR, "Failed to open IPv4 socket for "
443 		    "listing network interfaces (%s)", strerror(errno));
444 		return (NULL);
445 	}
446 
447 	lifn.lifn_family = AF_INET;
448 	lifn.lifn_flags = 0;
449 	if (ioctl(sock, SIOCGLIFNUM, (char *)&lifn) < 0) {
450 		logger(LOG_ERR,
451 		    "Failed to find the number of network interfaces (%s)",
452 		    strerror(errno));
453 		close(sock);
454 		return (NULL);
455 	}
456 
457 	if (lifn.lifn_count < 1) {
458 		logger(LOG_ERR, "No IPv4 network interfaces found");
459 		close(sock);
460 		return (NULL);
461 	}
462 
463 	lifc.lifc_family = AF_INET;
464 	lifc.lifc_flags = 0;
465 	lifc.lifc_len = lifn.lifn_count * sizeof (struct lifreq);
466 	lifc.lifc_buf = malloc(lifc.lifc_len);
467 
468 	if (lifc.lifc_buf == NULL) {
469 		logger(LOG_ERR, "Out of memory");
470 		close(sock);
471 		return (NULL);
472 	}
473 
474 	if (ioctl(sock, SIOCGLIFCONF, (char *)&lifc) < 0) {
475 		logger(LOG_ERR, "Failed to list network interfaces (%s)",
476 		    strerror(errno));
477 		free(lifc.lifc_buf);
478 		close(sock);
479 		return (NULL);
480 	}
481 
482 	n = lifc.lifc_len / (int)sizeof (struct lifreq);
483 
484 	if ((results = calloc(n + 1, sizeof (ad_subnet_t))) == NULL) {
485 		free(lifc.lifc_buf);
486 		close(sock);
487 		return (NULL);
488 	}
489 
490 	for (i = 0, lifrp = lifc.lifc_req; i < n; i++, lifrp++) {
491 		if (ioctl(sock, SIOCGLIFFLAGS, lifrp) < 0)
492 			continue;
493 
494 		if ((lifrp->lifr_flags & IFF_UP) == 0)
495 			continue;
496 
497 		if (ioctl(sock, SIOCGLIFSUBNET, lifrp) < 0)
498 			continue;
499 
500 		prefix_len = lifrp->lifr_addrlen;
501 
502 		s = inet_ntoa(((struct sockaddr_in *)
503 		    &lifrp->lifr_addr)->sin_addr);
504 
505 		(void) snprintf(results[i].subnet, sizeof (ad_subnet_t),
506 		    "%s/%d", s, prefix_len);
507 	}
508 
509 	free(lifc.lifc_buf);
510 	close(sock);
511 
512 	return (results);
513 }
514 
515 static int
516 cmpsubnets(ad_subnet_t *subnets1, ad_subnet_t *subnets2)
517 {
518 	int num_subnets1;
519 	int num_subnets2;
520 	boolean_t matched;
521 	int i, j;
522 
523 	for (i = 0; subnets1[i].subnet[0] != '\0'; i++)
524 		continue;
525 	num_subnets1 = i;
526 
527 	for (i = 0; subnets2[i].subnet[0] != '\0'; i++)
528 		continue;
529 	num_subnets2 = i;
530 
531 	if (num_subnets1 != num_subnets2)
532 		return (1);
533 
534 	for (i = 0;  i < num_subnets1; i++) {
535 		matched = B_FALSE;
536 		for (j = 0; j < num_subnets2; j++) {
537 			if (strcmp(subnets1[i].subnet,
538 			    subnets2[j].subnet) == 0) {
539 				matched = B_TRUE;
540 				break;
541 			}
542 		}
543 		if (!matched)
544 			return (1);
545 	}
546 	return (0);
547 }
548 
549 
550 
551 
552 /* Convert a DN's DC components into a DNS domainname */
553 char *
554 DN_to_DNS(const char *dn_name)
555 {
556 	char	dns[DNS_MAX_NAME];
557 	char	*dns_name;
558 	int	i, j;
559 	int	num = 0;
560 
561 	j = 0;
562 	i = 0;
563 
564 	if (dn_name == NULL)
565 		return (NULL);
566 	/*
567 	 * Find all DC=<value> and form DNS name of the
568 	 * form <value1>.<value2>...
569 	 */
570 	while (dn_name[i] != '\0') {
571 		if (strncasecmp(&dn_name[i], "DC=", 3) == 0) {
572 			i += 3;
573 			if (dn_name[i] != '\0' && num > 0)
574 				dns[j++] = '.';
575 			while (dn_name[i] != '\0' &&
576 			    dn_name[i] != ',' && dn_name[i] != '+')
577 				dns[j++] = dn_name[i++];
578 			num++;
579 		} else {
580 			/* Skip attr=value as it is not DC= */
581 			while (dn_name[i] != '\0' &&
582 			    dn_name[i] != ',' && dn_name[i] != '+')
583 				i++;
584 		}
585 		/* Skip over separator ','  or '+' */
586 		if (dn_name[i] != '\0') i++;
587 	}
588 	dns[j] = '\0';
589 	dns_name = malloc(j + 1);
590 	if (dns_name != NULL)
591 		(void) strlcpy(dns_name, dns, j + 1);
592 	return (dns_name);
593 }
594 
595 
596 /* Format the DN of an AD LDAP subnet object for some subnet */
597 static char *
598 subnet_to_DN(const char *subnet, const char *baseDN)
599 {
600 	char *result;
601 	int len;
602 
603 	len = snprintf(NULL, 0,
604 	    "CN=%s,CN=Subnets,CN=Sites,%s",
605 	    subnet, baseDN) + 1;
606 
607 	result = malloc(len);
608 	if (result != NULL)
609 		(void) snprintf(result, len,
610 		    "CN=%s,CN=Subnets,CN=Sites,%s",
611 		    subnet, baseDN);
612 	return (result);
613 }
614 
615 
616 /* Make a list of subnet object DNs from a list of subnets */
617 static char **
618 subnets_to_DNs(ad_subnet_t *subnets, const char *base_dn)
619 {
620 	char **results;
621 	int i, j;
622 
623 	for (i = 0; subnets[i].subnet[0] != '\0'; i++)
624 		continue;
625 
626 	results = calloc(i + 1, sizeof (char *));
627 	if (results == NULL)
628 		return (NULL);
629 
630 	for (i = 0; subnets[i].subnet[0] != '\0'; i++) {
631 		if ((results[i] = subnet_to_DN(subnets[i].subnet, base_dn))
632 		    == NULL) {
633 			for (j = 0; j < i; j++)
634 				free(results[j]);
635 			free(results);
636 			return (NULL);
637 		}
638 	}
639 
640 	return (results);
641 }
642 
643 
644 /* Compare SRC RRs; used with qsort() */
645 static int
646 srvcmp(idmap_ad_disc_ds_t *s1, idmap_ad_disc_ds_t *s2)
647 {
648 	if (s1->priority < s2->priority)
649 		return (1);
650 	else if (s1->priority > s2->priority)
651 		return (-1);
652 
653 	if (s1->weight < s2->weight)
654 		return (1);
655 	else if (s1->weight > s2->weight)
656 		return (-1);
657 
658 	return (0);
659 }
660 
661 
662 /*
663  * Query or search the SRV RRs for a given name.
664  *
665  * If name == NULL then search (as in res_nsearch(3RESOLV), honoring any
666  * search list/option), else query (as in res_nquery(3RESOLV)).
667  *
668  * The output TTL will be the one of the SRV RR with the lowest TTL.
669  */
670 idmap_ad_disc_ds_t *
671 srv_query(res_state state, const char *svc_name, const char *dname,
672 		char **rrname, uint32_t *ttl)
673 {
674 	idmap_ad_disc_ds_t *srv;
675 	idmap_ad_disc_ds_t *srv_res;
676 	union {
677 		HEADER hdr;
678 		uchar_t buf[NS_MAXMSG];
679 	} msg;
680 	int len, cnt, qdcount, ancount;
681 	uchar_t *ptr, *eom;
682 	uchar_t *end;
683 	uint16_t type;
684 	/* LINTED  E_FUNC_SET_NOT_USED */
685 	uint16_t class;
686 	uint32_t rttl;
687 	uint16_t size;
688 	char namebuf[NS_MAXDNAME];
689 
690 	if (state == NULL)
691 		return (NULL);
692 
693 	/* Set negative result TTL */
694 	*ttl = 5 * 60;
695 
696 	/* 1. query necessary resource records */
697 
698 	/* Search, querydomain or query */
699 	if (rrname != NULL) {
700 		*rrname = NULL;
701 		len = res_nsearch(state, svc_name, C_IN, T_SRV,
702 		    msg.buf, sizeof (msg.buf));
703 		logger(LOG_DEBUG, "Searching DNS for SRV RRs named '%s'",
704 		    svc_name);
705 		if (len < 0) {
706 			logger(LOG_DEBUG, "DNS search for '%s' failed (%s)",
707 			    svc_name, hstrerror(state->res_h_errno));
708 			return (NULL);
709 		}
710 	} else if (dname != NULL) {
711 		logger(LOG_DEBUG,
712 		    "Querying DNS for SRV RRs named '%s' for '%s' ",
713 		    svc_name, dname);
714 
715 		len = res_nquerydomain(state, svc_name, dname, C_IN, T_SRV,
716 		    msg.buf, sizeof (msg.buf));
717 
718 		if (len < 0) {
719 			logger(LOG_DEBUG,
720 			    "DNS query for '%s' for '%s' failed (%s)",
721 			    svc_name, dname, hstrerror(state->res_h_errno));
722 			return (NULL);
723 		}
724 	}
725 
726 	if (len > sizeof (msg.buf)) {
727 		logger(LOG_ERR, "DNS query %ib message doesn't fit"
728 		    " into %ib buffer",
729 		    len, sizeof (msg.buf));
730 		return (NULL);
731 	}
732 
733 	/* 2. parse the reply, skip header and question sections */
734 
735 	ptr = msg.buf + sizeof (msg.hdr);
736 	eom = msg.buf + len;
737 	qdcount = ntohs(msg.hdr.qdcount);
738 	ancount = ntohs(msg.hdr.ancount);
739 
740 	for (cnt = qdcount; cnt > 0; --cnt) {
741 		if ((len = dn_skipname(ptr, eom)) < 0) {
742 			logger(LOG_ERR, "DNS query invalid message format");
743 			return (NULL);
744 		}
745 		ptr += len + QFIXEDSZ;
746 	}
747 
748 	/* 3. walk through the answer section */
749 
750 	srv_res = calloc(ancount + 1, sizeof (idmap_ad_disc_ds_t));
751 	*ttl = (uint32_t)-1;
752 
753 	for (srv = srv_res, cnt = ancount;
754 	    cnt > 0; --cnt, srv++) {
755 
756 		len = dn_expand(msg.buf, eom, ptr, namebuf,
757 		    sizeof (namebuf));
758 		if (len < 0) {
759 			logger(LOG_ERR, "DNS query invalid message format");
760 			return (NULL);
761 		}
762 		if (rrname != NULL && *rrname == NULL)
763 			*rrname = strdup(namebuf);
764 		ptr += len;
765 		NS_GET16(type, ptr);
766 		NS_GET16(class, ptr);
767 		NS_GET32(rttl, ptr);
768 		NS_GET16(size, ptr);
769 		if ((end = ptr + size) > eom) {
770 			logger(LOG_ERR, "DNS query invalid message format");
771 			return (NULL);
772 		}
773 
774 		if (type != T_SRV) {
775 			ptr = end;
776 			continue;
777 		}
778 
779 		NS_GET16(srv->priority, ptr);
780 		NS_GET16(srv->weight, ptr);
781 		NS_GET16(srv->port, ptr);
782 		len = dn_expand(msg.buf, eom, ptr, srv->host,
783 		    sizeof (srv->host));
784 		if (len < 0) {
785 			logger(LOG_ERR, "DNS query invalid SRV record");
786 			return (NULL);
787 		}
788 
789 		if (rttl < *ttl)
790 			*ttl = rttl;
791 
792 		logger(LOG_DEBUG, "Found %s %d IN SRV [%d][%d] %s:%d",
793 		    namebuf, rttl, srv->priority, srv->weight, srv->host,
794 		    srv->port);
795 
796 		/* 3. move ptr to the end of current record */
797 
798 		ptr = end;
799 	}
800 
801 	if (ancount > 1)
802 		qsort(srv_res, ancount, sizeof (*srv_res),
803 		    (int (*)(const void *, const void *))srvcmp);
804 
805 	return (srv_res);
806 }
807 
808 
809 /*
810  * A utility function to bind to a Directory server
811  */
812 
813 static LDAP*
814 ldap_lookup_init(idmap_ad_disc_ds_t *ds)
815 {
816 	int 	i;
817 	int	rc, ldversion;
818 	int	zero = 0;
819 	int 	timeoutms = 5 * 1000;
820 	char 	*saslmech = "GSSAPI";
821 	uint32_t saslflags = LDAP_SASL_INTERACTIVE;
822 	LDAP 	*ld = NULL;
823 
824 	for (i = 0; ds[i].host[0] != '\0'; i++) {
825 		ld = ldap_init(ds[i].host, ds[i].port);
826 		if (ld == NULL) {
827 			logger(LOG_DEBUG, "Couldn't connect to "
828 			    "AD DC %s:%d (%s)",
829 			    ds[i].host, ds[i].port,
830 			    strerror(errno));
831 			continue;
832 		}
833 
834 		ldversion = LDAP_VERSION3;
835 		(void) ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION,
836 		    &ldversion);
837 
838 		(void) ldap_set_option(ld, LDAP_OPT_REFERRALS,
839 		    LDAP_OPT_OFF);
840 		(void) ldap_set_option(ld, LDAP_OPT_TIMELIMIT, &zero);
841 		(void) ldap_set_option(ld, LDAP_OPT_SIZELIMIT, &zero);
842 		/* setup TCP/IP connect timeout */
843 		(void) ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT,
844 		    &timeoutms);
845 		(void) ldap_set_option(ld, LDAP_OPT_RESTART,
846 		    LDAP_OPT_ON);
847 
848 		rc = ldap_sasl_interactive_bind_s(ld, "" /* binddn */,
849 		    saslmech, NULL, NULL, saslflags, &saslcallback,
850 		    NULL /* defaults */);
851 		if (rc == LDAP_SUCCESS)
852 			break;
853 
854 		logger(LOG_INFO, "LDAP SASL bind to %s:%d failed (%s)",
855 		    ds[i].host, ds[i].port, ldap_err2string(rc));
856 		(void) ldap_unbind(ld);
857 		ld = NULL;
858 	}
859 	return (ld);
860 }
861 
862 
863 
864 /*
865  * A utility function to get the value of some attribute of one of one
866  * or more AD LDAP objects named by the dn_list; first found one wins.
867  */
868 static char *
869 ldap_lookup_entry_attr(LDAP **ld, idmap_ad_disc_ds_t *domainControllers,
870 			char **dn_list, char *attr)
871 {
872 	int 	i;
873 	int	rc;
874 	int	scope = LDAP_SCOPE_BASE;
875 	char	*attrs[2];
876 	LDAPMessage *results = NULL;
877 	LDAPMessage *entry;
878 	char	**values = NULL;
879 	char	*val = NULL;
880 
881 	attrs[0] = attr;
882 	attrs[1] = NULL;
883 
884 	if (*ld == NULL)
885 		*ld = ldap_lookup_init(domainControllers);
886 
887 	if (*ld == NULL)
888 		return (NULL);
889 
890 	for (i = 0; dn_list[i] != NULL; i++) {
891 		rc = ldap_search_s(*ld, dn_list[i], scope,
892 		    "(objectclass=*)", attrs, 0, &results);
893 		if (rc == LDAP_SUCCESS) {
894 			for (entry = ldap_first_entry(*ld, results);
895 			    entry != NULL && values == NULL;
896 			    entry = ldap_next_entry(*ld, entry)) {
897 				values = ldap_get_values(
898 				    *ld, entry, attr);
899 			}
900 
901 			if (values != NULL) {
902 				(void) ldap_msgfree(results);
903 				val = strdup(values[0]);
904 				ldap_value_free(values);
905 				return (val);
906 			}
907 		}
908 		if (results != NULL) {
909 			(void) ldap_msgfree(results);
910 			results = NULL;
911 		}
912 	}
913 
914 	return (NULL);
915 }
916 
917 
918 /*
919  * Lookup the trusted domains in the global catalog.
920  *
921  * Returns:
922  *	array of trusted domains which is terminated by
923  *		an empty trusted domain.
924  *	NULL an error occured
925  */
926 ad_disc_trusteddomains_t *
927 ldap_lookup_trusted_domains(LDAP **ld, idmap_ad_disc_ds_t *globalCatalog,
928 			char *base_dn)
929 {
930 	int		scope = LDAP_SCOPE_SUBTREE;
931 	char		*attrs[3];
932 	int		rc;
933 	LDAPMessage	*results = NULL;
934 	LDAPMessage	*entry;
935 	char		*filter;
936 	char		**partner = NULL;
937 	char		**direction = NULL;
938 	int		num = 0;
939 	ad_disc_trusteddomains_t *trusted_domains = NULL;
940 
941 
942 	if (*ld == NULL)
943 		*ld = ldap_lookup_init(globalCatalog);
944 
945 	if (*ld == NULL)
946 		return (NULL);
947 
948 	attrs[0] = "trustPartner";
949 	attrs[1] = "trustDirection";
950 	attrs[2] = NULL;
951 
952 	/* trustDirection values - inbound = 1 and bidirectional = 3 */
953 	filter = "(&(objectclass=trustedDomain)"
954 	    "(|(trustDirection=3)(trustDirection=1)))";
955 
956 	rc = ldap_search_s(*ld, base_dn, scope, filter, attrs, 0, &results);
957 	if (rc == LDAP_SUCCESS) {
958 		for (entry = ldap_first_entry(*ld, results);
959 		    entry != NULL; entry = ldap_next_entry(*ld, entry)) {
960 			partner = ldap_get_values(*ld, entry, "trustPartner");
961 			direction = ldap_get_values(
962 			    *ld, entry, "trustDirection");
963 
964 			if (partner != NULL && direction != NULL) {
965 				num++;
966 				trusted_domains = realloc(trusted_domains,
967 				    (num + 1) *
968 				    sizeof (ad_disc_trusteddomains_t));
969 				if (trusted_domains == NULL) {
970 					ldap_value_free(partner);
971 					ldap_value_free(direction);
972 					ldap_msgfree(results);
973 					return (NULL);
974 				}
975 				/* Last element should be zero */
976 				memset(&trusted_domains[num], 0,
977 				    sizeof (ad_disc_trusteddomains_t));
978 				strcpy(trusted_domains[num - 1].domain,
979 				    partner[0]);
980 				trusted_domains[num - 1].direction =
981 				    atoi(direction[0]);
982 			}
983 			if (partner != NULL)
984 				ldap_value_free(partner);
985 			if (direction != NULL)
986 				ldap_value_free(direction);
987 		}
988 	} else if (rc == LDAP_NO_RESULTS_RETURNED) {
989 		/* This is not an error - return empty trusted domain */
990 		trusted_domains = calloc(1, sizeof (ad_disc_trusteddomains_t));
991 	}
992 	if (results != NULL)
993 		ldap_msgfree(results);
994 
995 	return (trusted_domains);
996 }
997 
998 
999 /*
1000  * This functions finds all the domains in a forest.
1001  */
1002 ad_disc_domainsinforest_t *
1003 ldap_lookup_domains_in_forest(LDAP **ld, idmap_ad_disc_ds_t *globalCatalogs)
1004 {
1005 	static char	*attrs[] = {
1006 		"objectSid",
1007 		NULL,
1008 	};
1009 	int		rc;
1010 	LDAPMessage	*result = NULL;
1011 	LDAPMessage	*entry;
1012 	int		ndomains = 0;
1013 	int		nresults;
1014 	ad_disc_domainsinforest_t *domains = NULL;
1015 
1016 	if (*ld == NULL)
1017 		*ld = ldap_lookup_init(globalCatalogs);
1018 
1019 	if (*ld == NULL)
1020 		return (NULL);
1021 
1022 	logger(LOG_DEBUG, "Looking for domains in forest...");
1023 	/* Find domains */
1024 	rc = ldap_search_s(*ld, "", LDAP_SCOPE_SUBTREE,
1025 	    "(objectClass=Domain)", attrs, 0, &result);
1026 	if (rc != LDAP_SUCCESS)
1027 		goto err;
1028 
1029 	nresults = ldap_count_entries(*ld, result);
1030 	domains = calloc(nresults + 1, sizeof (*domains));
1031 	if (domains == NULL)
1032 		goto err;
1033 
1034 	for (entry = ldap_first_entry(*ld, result);
1035 	    entry != NULL;
1036 	    entry = ldap_next_entry(*ld, entry)) {
1037 		struct berval	**sid_ber;
1038 		adutils_sid_t	sid;
1039 		char		*sid_str;
1040 		char 		*name;
1041 
1042 		sid_ber = ldap_get_values_len(*ld, entry,
1043 		    "objectSid");
1044 		if (sid_ber == NULL)
1045 			continue;
1046 
1047 		rc = adutils_getsid(sid_ber[0], &sid);
1048 		ldap_value_free_len(sid_ber);
1049 		if (rc < 0)
1050 			goto err;
1051 
1052 		if ((sid_str = adutils_sid2txt(&sid)) == NULL)
1053 			goto err;
1054 
1055 		strcpy(domains[ndomains].sid, sid_str);
1056 		free(sid_str);
1057 
1058 		name = DN_to_DNS(ldap_get_dn(*ld, entry));
1059 		if (name == NULL)
1060 			goto err;
1061 
1062 		strcpy(domains[ndomains].domain, name);
1063 		free(name);
1064 
1065 		logger(LOG_DEBUG, "    found %s", domains[ndomains].domain);
1066 
1067 		ndomains++;
1068 	}
1069 
1070 	if (ndomains == 0)
1071 		goto err;
1072 
1073 	if (ndomains < nresults) {
1074 		ad_disc_domainsinforest_t *tmp;
1075 		tmp = realloc(domains, (ndomains + 1) * sizeof (*domains));
1076 		if (tmp == NULL)
1077 			goto err;
1078 		domains = tmp;
1079 	}
1080 
1081 	if (result != NULL)
1082 		ldap_msgfree(result);
1083 
1084 	return (domains);
1085 
1086 err:
1087 	free(domains);
1088 	if (result != NULL)
1089 		ldap_msgfree(result);
1090 	return (NULL);
1091 }
1092 
1093 
1094 ad_disc_t
1095 ad_disc_init(void)
1096 {
1097 	struct ad_disc *ctx;
1098 	ctx = calloc(1, sizeof (struct ad_disc));
1099 	if (ctx != NULL)
1100 		DO_RES_NINIT(ctx);
1101 
1102 	ctx->domain_name.type = AD_STRING;
1103 	ctx->domain_controller.type = AD_DIRECTORY;
1104 	ctx->site_name.type = AD_STRING;
1105 	ctx->forest_name.type = AD_STRING;
1106 	ctx->global_catalog.type = AD_DIRECTORY;
1107 	ctx->domains_in_forest.type = AD_DOMAINS_IN_FOREST;
1108 	ctx->trusted_domains.type = AD_TRUSTED_DOMAINS;
1109 	/* Site specific versions */
1110 	ctx->site_domain_controller.type = AD_DIRECTORY;
1111 	ctx->site_global_catalog.type = AD_DIRECTORY;
1112 	return (ctx);
1113 }
1114 
1115 
1116 void
1117 ad_disc_fini(ad_disc_t ctx)
1118 {
1119 	if (ctx == NULL)
1120 		return;
1121 
1122 	if (ctx->res_ninitted)
1123 		res_ndestroy(&ctx->res_state);
1124 
1125 	if (ctx->subnets != NULL)
1126 		free(ctx->subnets);
1127 
1128 	if (ctx->domain_name.value != NULL)
1129 		free(ctx->domain_name.value);
1130 
1131 	if (ctx->domain_controller.value != NULL)
1132 		free(ctx->domain_controller.value);
1133 
1134 	if (ctx->site_name.value != NULL)
1135 		free(ctx->site_name.value);
1136 
1137 	if (ctx->forest_name.value != NULL)
1138 		free(ctx->forest_name.value);
1139 
1140 	if (ctx->global_catalog.value != NULL)
1141 		free(ctx->global_catalog.value);
1142 
1143 	if (ctx->domains_in_forest.value != NULL)
1144 		free(ctx->domains_in_forest.value);
1145 
1146 	if (ctx->trusted_domains.value != NULL)
1147 		free(ctx->trusted_domains.value);
1148 
1149 	/* Site specific versions */
1150 	if (ctx->site_domain_controller.value != NULL)
1151 		free(ctx->site_domain_controller.value);
1152 
1153 	if (ctx->site_global_catalog.value != NULL)
1154 		free(ctx->site_global_catalog.value);
1155 
1156 	free(ctx);
1157 }
1158 
1159 void
1160 ad_disc_refresh(ad_disc_t ctx)
1161 {
1162 	if (ctx->res_ninitted)
1163 		res_ndestroy(&ctx->res_state);
1164 	(void) memset(&ctx->res_state, 0, sizeof (ctx->res_state));
1165 	ctx->res_ninitted = res_ninit(&ctx->res_state) != -1;
1166 
1167 	if (ctx->domain_name.state == AD_STATE_AUTO)
1168 		ctx->domain_name.state = AD_STATE_INVALID;
1169 
1170 	if (ctx->domain_controller.state == AD_STATE_AUTO)
1171 		ctx->domain_controller.state  = AD_STATE_INVALID;
1172 
1173 	if (ctx->site_name.state == AD_STATE_AUTO)
1174 		ctx->site_name.state = AD_STATE_INVALID;
1175 
1176 	if (ctx->forest_name.state == AD_STATE_AUTO)
1177 		ctx->forest_name.state = AD_STATE_INVALID;
1178 
1179 	if (ctx->global_catalog.state == AD_STATE_AUTO)
1180 		ctx->global_catalog.state = AD_STATE_INVALID;
1181 
1182 	if (ctx->domains_in_forest.state == AD_STATE_AUTO)
1183 		ctx->domains_in_forest.state  = AD_STATE_INVALID;
1184 
1185 	if (ctx->trusted_domains.state == AD_STATE_AUTO)
1186 		ctx->trusted_domains.state  = AD_STATE_INVALID;
1187 
1188 	if (ctx->site_domain_controller.state == AD_STATE_AUTO)
1189 		ctx->site_domain_controller.state  = AD_STATE_INVALID;
1190 
1191 	if (ctx->site_global_catalog.state == AD_STATE_AUTO)
1192 		ctx->site_global_catalog.state = AD_STATE_INVALID;
1193 }
1194 
1195 
1196 
1197 /* Discover joined Active Directory domainName */
1198 static ad_item_t *
1199 validate_DomainName(ad_disc_t ctx)
1200 {
1201 	idmap_ad_disc_ds_t *domain_controller = NULL;
1202 	char *dname, *srvname;
1203 	uint32_t ttl = 0;
1204 	int len;
1205 
1206 	if (is_valid(&ctx->domain_name))
1207 		return (&ctx->domain_name);
1208 
1209 
1210 	/* Try to find our domain by searching for DCs for it */
1211 	DO_RES_NINIT(ctx);
1212 	domain_controller = srv_query(&ctx->res_state, LDAP_SRV_HEAD
1213 	    DC_SRV_TAIL, ctx->domain_name.value, &srvname, &ttl);
1214 
1215 	/*
1216 	 * If we can't find DCs by via res_nsearch() then there's no
1217 	 * point in trying anything else to discover the AD domain name.
1218 	 */
1219 	if (domain_controller == NULL)
1220 		return (NULL);
1221 
1222 	free(domain_controller);
1223 	/*
1224 	 * We have the FQDN of the SRV RR name, so now we extract the
1225 	 * domainname suffix from it.
1226 	 */
1227 	dname = strdup(srvname + strlen(LDAP_SRV_HEAD DC_SRV_TAIL) +
1228 	    1 /* for the dot between RR name and domainname */);
1229 
1230 	free(srvname);
1231 
1232 	if (dname == NULL) {
1233 		logger(LOG_ERR, "Out of memory");
1234 		return (NULL);
1235 	}
1236 
1237 	/* Eat any trailing dot */
1238 	len = strlen(dname);
1239 	if (len > 0 && dname[len - 1] == '.')
1240 		dname[len - 1] = '\0';
1241 
1242 	update_item(&ctx->domain_name, dname, AD_STATE_AUTO, ttl);
1243 
1244 	return (&ctx->domain_name);
1245 }
1246 
1247 
1248 char *
1249 ad_disc_get_DomainName(ad_disc_t ctx, boolean_t *auto_discovered)
1250 {
1251 	char *domain_name = NULL;
1252 	ad_item_t *domain_name_item;
1253 
1254 	domain_name_item = validate_DomainName(ctx);
1255 
1256 	if (domain_name_item) {
1257 		domain_name = strdup(domain_name_item->value);
1258 		if (auto_discovered != NULL)
1259 			*auto_discovered =
1260 			    (domain_name_item->state == AD_STATE_AUTO);
1261 	} else if (auto_discovered != NULL)
1262 		*auto_discovered = B_FALSE;
1263 
1264 	return (domain_name);
1265 }
1266 
1267 
1268 /* Discover domain controllers */
1269 static ad_item_t *
1270 validate_DomainController(ad_disc_t ctx, enum ad_disc_req req)
1271 {
1272 	uint32_t ttl = 0;
1273 	idmap_ad_disc_ds_t *domain_controller = NULL;
1274 	boolean_t validate_global = B_FALSE;
1275 	boolean_t validate_site = B_FALSE;
1276 	ad_item_t *domain_name_item;
1277 	ad_item_t *site_name_item = NULL;
1278 
1279 	/* If the values is fixed there will not be a site specific version */
1280 	if (is_fixed(&ctx->domain_controller))
1281 		return (&ctx->domain_controller);
1282 
1283 	domain_name_item = validate_DomainName(ctx);
1284 	if (domain_name_item == NULL)
1285 		return (NULL);
1286 
1287 	if (req == AD_DISC_GLOBAL)
1288 		validate_global = B_TRUE;
1289 	else {
1290 		site_name_item = validate_SiteName(ctx);
1291 		if (site_name_item != NULL)
1292 			validate_site = B_TRUE;
1293 		else if (req == AD_DISC_PREFER_SITE)
1294 			validate_global = B_TRUE;
1295 	}
1296 
1297 	if (validate_global) {
1298 		if (!is_valid(&ctx->domain_controller) ||
1299 		    is_changed(&ctx->domain_controller, PARAM1,
1300 		    domain_name_item)) {
1301 			/*
1302 			 * Lookup DNS SRV RR named
1303 			 * _ldap._tcp.dc._msdcs.<DomainName>
1304 			 */
1305 			DO_RES_NINIT(ctx);
1306 			domain_controller = srv_query(&ctx->res_state,
1307 			    LDAP_SRV_HEAD DC_SRV_TAIL,
1308 			    domain_name_item->value, NULL, &ttl);
1309 
1310 			if (domain_controller == NULL)
1311 				return (NULL);
1312 
1313 			update_item(&ctx->domain_controller, domain_controller,
1314 			    AD_STATE_AUTO, ttl);
1315 			update_version(&ctx->domain_controller, PARAM1,
1316 			    domain_name_item);
1317 		}
1318 		return (&ctx->domain_controller);
1319 	}
1320 
1321 	if (validate_site) {
1322 		if (!is_valid(&ctx->site_domain_controller) ||
1323 		    is_changed(&ctx->site_domain_controller, PARAM1,
1324 		    domain_name_item) ||
1325 		    is_changed(&ctx->site_domain_controller, PARAM2,
1326 		    site_name_item)) {
1327 			char rr_name[DNS_MAX_NAME];
1328 			/*
1329 			 * Lookup DNS SRV RR named
1330 			 * _ldap._tcp.<SiteName>._sites.dc._msdcs.<DomainName>
1331 			 */
1332 			(void) snprintf(rr_name, sizeof (rr_name),
1333 			    LDAP_SRV_HEAD SITE_SRV_MIDDLE DC_SRV_TAIL,
1334 			    site_name_item->value);
1335 			DO_RES_NINIT(ctx);
1336 			domain_controller = srv_query(&ctx->res_state, rr_name,
1337 			    domain_name_item->value, NULL, &ttl);
1338 			if (domain_controller == NULL)
1339 				return (NULL);
1340 
1341 			update_item(&ctx->site_domain_controller,
1342 			    domain_controller, AD_STATE_AUTO, ttl);
1343 			update_version(&ctx->site_domain_controller, PARAM1,
1344 			    domain_name_item);
1345 			update_version(&ctx->site_domain_controller, PARAM2,
1346 			    site_name_item);
1347 		}
1348 		return (&ctx->site_domain_controller);
1349 	}
1350 	return (NULL);
1351 }
1352 
1353 idmap_ad_disc_ds_t *
1354 ad_disc_get_DomainController(ad_disc_t ctx, enum ad_disc_req req,
1355 			boolean_t *auto_discovered)
1356 {
1357 	ad_item_t *domain_controller_item;
1358 	idmap_ad_disc_ds_t *domain_controller = NULL;
1359 
1360 	domain_controller_item = validate_DomainController(ctx, req);
1361 
1362 	if (domain_controller_item != NULL) {
1363 		domain_controller = ds_dup(domain_controller_item->value);
1364 		if (auto_discovered != NULL)
1365 			*auto_discovered =
1366 			    (domain_controller_item->state == AD_STATE_AUTO);
1367 	} else if (auto_discovered != NULL)
1368 		*auto_discovered = B_FALSE;
1369 
1370 	return (domain_controller);
1371 }
1372 
1373 
1374 /* Discover site name (for multi-homed systems the first one found wins) */
1375 static ad_item_t *
1376 validate_SiteName(ad_disc_t ctx)
1377 {
1378 	LDAP *ld = NULL;
1379 	ad_subnet_t *subnets = NULL;
1380 	char **dn_subnets = NULL;
1381 	char *dn_root[2];
1382 	char *config_naming_context = NULL;
1383 	char *site_object = NULL;
1384 	char *site_name = NULL;
1385 	char *forest_name;
1386 	int len;
1387 	int i;
1388 	boolean_t update_required = B_FALSE;
1389 	ad_item_t *domain_controller_item;
1390 
1391 	if (is_fixed(&ctx->site_name))
1392 		return (&ctx->site_name);
1393 
1394 	/* Can't rely on site-specific DCs */
1395 	domain_controller_item = validate_DomainController(ctx, AD_DISC_GLOBAL);
1396 	if (domain_controller_item == NULL)
1397 		return (NULL);
1398 
1399 	if (!is_valid(&ctx->site_name) ||
1400 	    is_changed(&ctx->site_name, PARAM1, &ctx->domain_controller) ||
1401 	    ctx->subnets == NULL || ctx->subnets_changed) {
1402 		subnets = find_subnets();
1403 		ctx->subnets_last_check = time(NULL);
1404 		update_required = B_TRUE;
1405 	} else if (ctx->subnets_last_check + 60 < time(NULL)) {
1406 		subnets = find_subnets();
1407 		ctx->subnets_last_check = time(NULL);
1408 		if (cmpsubnets(ctx->subnets, subnets) != 0)
1409 			update_required = B_TRUE;
1410 	}
1411 
1412 	if (!update_required) {
1413 		free(subnets);
1414 		return (&ctx->site_name);
1415 	}
1416 
1417 	if (subnets == NULL)
1418 		return (NULL);
1419 
1420 	dn_root[0] = "";
1421 	dn_root[1] = NULL;
1422 
1423 	config_naming_context = ldap_lookup_entry_attr(
1424 	    &ld, ctx->domain_controller.value,
1425 	    dn_root, "configurationNamingContext");
1426 	if (config_naming_context == NULL)
1427 		goto out;
1428 	/*
1429 	 * configurationNamingContext also provides the Forest
1430 	 * Name.
1431 	 */
1432 	if (!is_fixed(&ctx->forest_name)) {
1433 		/*
1434 		 * The configurationNamingContext should be of
1435 		 * form:
1436 		 * CN=Configuration,<DNforestName>
1437 		 * Remove the first part and convert to DNS form
1438 		 * (replace ",DC=" with ".")
1439 		 */
1440 		char *str = "CN=Configuration,";
1441 		int len = strlen(str);
1442 		if (strncasecmp(config_naming_context, str, len) == 0) {
1443 			forest_name = DN_to_DNS(config_naming_context + len);
1444 			update_item(&ctx->forest_name, forest_name,
1445 			    AD_STATE_AUTO, 0);
1446 		}
1447 	}
1448 
1449 	dn_subnets = subnets_to_DNs(subnets, config_naming_context);
1450 	if (dn_subnets == NULL)
1451 		goto out;
1452 
1453 	site_object = ldap_lookup_entry_attr(
1454 	    &ld, domain_controller_item->value,
1455 	    dn_subnets, "siteobject");
1456 	if (site_object != NULL) {
1457 		/*
1458 		 * The site object should be of the form
1459 		 * CN=<site>,CN=Sites,CN=Configuration,
1460 		 *		<DN Domain>
1461 		 */
1462 		if (strncasecmp(site_object, "CN=", 3) == 0) {
1463 			for (len = 0; site_object[len + 3] != ','; len++)
1464 					;
1465 			site_name = malloc(len + 1);
1466 			(void) strncpy(site_name, &site_object[3], len);
1467 			site_name[len] = '\0';
1468 			update_item(&ctx->site_name, site_name,
1469 			    AD_STATE_AUTO, 0);
1470 		}
1471 	}
1472 
1473 	if (ctx->subnets != NULL) {
1474 		free(ctx->subnets);
1475 		ctx->subnets = NULL;
1476 	}
1477 	ctx->subnets = subnets;
1478 	subnets = NULL;
1479 	ctx->subnets_changed = B_FALSE;
1480 
1481 out:
1482 	if (ld != NULL)
1483 		(void) ldap_unbind(ld);
1484 
1485 	if (dn_subnets != NULL) {
1486 		for (i = 0; dn_subnets[i] != NULL; i++)
1487 			free(dn_subnets[i]);
1488 		free(dn_subnets);
1489 	}
1490 	if (config_naming_context != NULL)
1491 		free(config_naming_context);
1492 	if (site_object != NULL)
1493 		free(site_object);
1494 
1495 	free(subnets);
1496 	if (site_name == NULL)
1497 		return (NULL);
1498 	return (&ctx->site_name);
1499 
1500 }
1501 
1502 
1503 char *
1504 ad_disc_get_SiteName(ad_disc_t ctx, boolean_t *auto_discovered)
1505 {
1506 	ad_item_t *site_name_item;
1507 	char	*site_name = NULL;
1508 
1509 	site_name_item = validate_SiteName(ctx);
1510 	if (site_name_item != NULL) {
1511 		site_name = strdup(site_name_item->value);
1512 		if (auto_discovered != NULL)
1513 			*auto_discovered =
1514 			    (site_name_item->state == AD_STATE_AUTO);
1515 	} else if (auto_discovered != NULL)
1516 		*auto_discovered = B_FALSE;
1517 
1518 	return (site_name);
1519 }
1520 
1521 
1522 
1523 /* Discover forest name */
1524 static ad_item_t *
1525 validate_ForestName(ad_disc_t ctx)
1526 {
1527 	LDAP	*ld = NULL;
1528 	char	*config_naming_context;
1529 	char	*forest_name = NULL;
1530 	char	*dn_list[2];
1531 	ad_item_t *domain_controller_item;
1532 
1533 	if (is_fixed(&ctx->forest_name))
1534 		return (&ctx->forest_name);
1535 	/*
1536 	 * We may not have a site name yet, so we won't rely on
1537 	 * site-specific DCs.  (But maybe we could replace
1538 	 * validate_ForestName() with validate_siteName()?)
1539 	 */
1540 	domain_controller_item = validate_DomainController(ctx, AD_DISC_GLOBAL);
1541 	if (domain_controller_item == NULL)
1542 		return (NULL);
1543 
1544 	if (!is_valid(&ctx->forest_name) ||
1545 	    is_changed(&ctx->forest_name, PARAM1, domain_controller_item)) {
1546 
1547 		dn_list[0] = "";
1548 		dn_list[1] = NULL;
1549 		config_naming_context = ldap_lookup_entry_attr(
1550 		    &ld, ctx->domain_controller.value,
1551 		    dn_list, "configurationNamingContext");
1552 		if (config_naming_context != NULL) {
1553 			/*
1554 			 * The configurationNamingContext should be of
1555 			 * form:
1556 			 * CN=Configuration,<DNforestName>
1557 			 * Remove the first part and convert to DNS form
1558 			 * (replace ",DC=" with ".")
1559 			 */
1560 			char *str = "CN=Configuration,";
1561 			int len = strlen(str);
1562 			if (strncasecmp(config_naming_context, str, len) == 0) {
1563 				forest_name = DN_to_DNS(
1564 				    config_naming_context + len);
1565 			}
1566 			free(config_naming_context);
1567 		}
1568 		if (ld != NULL)
1569 			(void) ldap_unbind(ld);
1570 
1571 		if (forest_name == NULL)
1572 			return (NULL);
1573 
1574 		update_item(&ctx->forest_name, forest_name, AD_STATE_AUTO, 0);
1575 		update_version(&ctx->forest_name, PARAM1,
1576 		    domain_controller_item);
1577 	}
1578 	return (&ctx->forest_name);
1579 }
1580 
1581 
1582 char *
1583 ad_disc_get_ForestName(ad_disc_t ctx, boolean_t *auto_discovered)
1584 {
1585 	ad_item_t *forest_name_item;
1586 	char	*forest_name = NULL;
1587 
1588 	forest_name_item = validate_ForestName(ctx);
1589 
1590 	if (forest_name_item != NULL) {
1591 		forest_name = strdup(forest_name_item->value);
1592 		if (auto_discovered != NULL)
1593 			*auto_discovered =
1594 			    (forest_name_item->state == AD_STATE_AUTO);
1595 	} else if (auto_discovered != NULL)
1596 		*auto_discovered = B_FALSE;
1597 
1598 	return (forest_name);
1599 }
1600 
1601 
1602 /* Discover global catalog servers */
1603 static ad_item_t *
1604 validate_GlobalCatalog(ad_disc_t ctx, enum ad_disc_req req)
1605 {
1606 	idmap_ad_disc_ds_t *global_catalog = NULL;
1607 	uint32_t ttl = 0;
1608 	boolean_t validate_global = B_FALSE;
1609 	boolean_t validate_site = B_FALSE;
1610 	ad_item_t *forest_name_item;
1611 	ad_item_t *site_name_item;
1612 
1613 	/* If the values is fixed there will not be a site specific version */
1614 	if (is_fixed(&ctx->global_catalog))
1615 		return (&ctx->global_catalog);
1616 
1617 	forest_name_item = validate_ForestName(ctx);
1618 	if (forest_name_item == NULL)
1619 		return (NULL);
1620 
1621 	if (req == AD_DISC_GLOBAL)
1622 		validate_global = B_TRUE;
1623 	else {
1624 		site_name_item = validate_SiteName(ctx);
1625 		if (site_name_item != NULL)
1626 			validate_site = B_TRUE;
1627 		else if (req == AD_DISC_PREFER_SITE)
1628 			validate_global = B_TRUE;
1629 	}
1630 
1631 	if (validate_global) {
1632 		if (!is_valid(&ctx->global_catalog) ||
1633 		    is_changed(&ctx->global_catalog, PARAM1,
1634 		    forest_name_item)) {
1635 			/*
1636 			 * Lookup DNS SRV RR named
1637 			 * _ldap._tcp.gc._msdcs.<ForestName>
1638 			 */
1639 			DO_RES_NINIT(ctx);
1640 			global_catalog =
1641 			    srv_query(&ctx->res_state,
1642 			    LDAP_SRV_HEAD GC_SRV_TAIL,
1643 			    ctx->forest_name.value, NULL, &ttl);
1644 
1645 			if (global_catalog == NULL)
1646 				return (NULL);
1647 
1648 			update_item(&ctx->global_catalog, global_catalog,
1649 			    AD_STATE_AUTO, ttl);
1650 			update_version(&ctx->global_catalog, PARAM1,
1651 			    forest_name_item);
1652 		}
1653 		return (&ctx->global_catalog);
1654 	}
1655 
1656 	if (validate_site) {
1657 		if (!is_valid(&ctx->site_global_catalog) ||
1658 		    is_changed(&ctx->site_global_catalog, PARAM1,
1659 		    forest_name_item) ||
1660 		    is_changed(&ctx->site_global_catalog, PARAM2,
1661 		    site_name_item)) {
1662 			char 	rr_name[DNS_MAX_NAME];
1663 
1664 			/*
1665 			 * Lookup DNS SRV RR named:
1666 			 * _ldap._tcp.<siteName>._sites.gc.
1667 			 *	_msdcs.<ForestName>
1668 			 */
1669 			(void) snprintf(rr_name,
1670 			    sizeof (rr_name),
1671 			    LDAP_SRV_HEAD SITE_SRV_MIDDLE GC_SRV_TAIL,
1672 			    ctx->site_name.value);
1673 			DO_RES_NINIT(ctx);
1674 			global_catalog = srv_query(&ctx->res_state, rr_name,
1675 			    ctx->forest_name.value, NULL, &ttl);
1676 
1677 			if (global_catalog == NULL)
1678 				return (NULL);
1679 			update_item(&ctx->site_global_catalog, global_catalog,
1680 			    AD_STATE_AUTO, ttl);
1681 			update_version(&ctx->site_global_catalog, PARAM1,
1682 			    forest_name_item);
1683 			update_version(&ctx->site_global_catalog, PARAM2,
1684 			    site_name_item);
1685 		}
1686 		return (&ctx->site_global_catalog);
1687 	}
1688 	return (NULL);
1689 }
1690 
1691 
1692 idmap_ad_disc_ds_t *
1693 ad_disc_get_GlobalCatalog(ad_disc_t ctx, enum ad_disc_req req,
1694 			boolean_t *auto_discovered)
1695 {
1696 	idmap_ad_disc_ds_t *global_catalog = NULL;
1697 	ad_item_t *global_catalog_item;
1698 
1699 	global_catalog_item = validate_GlobalCatalog(ctx, req);
1700 
1701 	if (global_catalog_item != NULL) {
1702 		global_catalog = ds_dup(global_catalog_item->value);
1703 		if (auto_discovered != NULL)
1704 			*auto_discovered =
1705 			    (global_catalog_item->state == AD_STATE_AUTO);
1706 	} else if (auto_discovered != NULL)
1707 		*auto_discovered = B_FALSE;
1708 
1709 	return (global_catalog);
1710 }
1711 
1712 
1713 static ad_item_t *
1714 validate_TrustedDomains(ad_disc_t ctx)
1715 {
1716 	LDAP *ld = NULL;
1717 	ad_item_t *global_catalog_item;
1718 	ad_item_t *forest_name_item;
1719 	ad_disc_trusteddomains_t *trusted_domains;
1720 	char *dn = NULL;
1721 	char *forest_name_dn;
1722 	int len;
1723 	int num_parts;
1724 
1725 	if (is_fixed(&ctx->trusted_domains))
1726 		return (&ctx->trusted_domains);
1727 
1728 	global_catalog_item = validate_GlobalCatalog(ctx, AD_DISC_GLOBAL);
1729 	if (global_catalog_item == NULL)
1730 		return (NULL);
1731 
1732 	forest_name_item = validate_ForestName(ctx);
1733 	if (forest_name_item == NULL)
1734 		return (NULL);
1735 
1736 	if (!is_valid(&ctx->trusted_domains) ||
1737 	    is_changed(&ctx->trusted_domains, PARAM1, global_catalog_item) ||
1738 	    is_changed(&ctx->trusted_domains, PARAM2, forest_name_item)) {
1739 
1740 		forest_name_dn = ldap_dns_to_dn(forest_name_item->value,
1741 		    &num_parts);
1742 		if (forest_name_dn == NULL)
1743 			return (NULL);
1744 
1745 		len = snprintf(NULL, 0, "CN=System,%s", forest_name_dn) + 1;
1746 		dn = malloc(len);
1747 		if (dn == NULL)  {
1748 			free(forest_name_dn);
1749 			return (NULL);
1750 		}
1751 		(void) snprintf(dn, len, "CN=System,%s", forest_name_dn);
1752 		free(forest_name_dn);
1753 
1754 		trusted_domains = ldap_lookup_trusted_domains(
1755 		    &ld, global_catalog_item->value, dn);
1756 
1757 		if (ld != NULL)
1758 			(void) ldap_unbind(ld);
1759 		free(dn);
1760 
1761 		if (trusted_domains == NULL)
1762 			return (NULL);
1763 
1764 		update_item(&ctx->trusted_domains, trusted_domains,
1765 		    AD_STATE_AUTO, 0);
1766 		update_version(&ctx->trusted_domains, PARAM1,
1767 		    global_catalog_item);
1768 		update_version(&ctx->trusted_domains, PARAM2,
1769 		    forest_name_item);
1770 	}
1771 
1772 	return (&ctx->trusted_domains);
1773 }
1774 
1775 
1776 ad_disc_trusteddomains_t *
1777 ad_disc_get_TrustedDomains(ad_disc_t ctx, boolean_t *auto_discovered)
1778 {
1779 	ad_disc_trusteddomains_t *trusted_domains = NULL;
1780 	ad_item_t *trusted_domains_item;
1781 
1782 	trusted_domains_item = validate_TrustedDomains(ctx);
1783 
1784 	if (trusted_domains_item != NULL) {
1785 		trusted_domains = td_dup(trusted_domains_item->value);
1786 		if (auto_discovered != NULL)
1787 			*auto_discovered =
1788 			    (trusted_domains_item->state == AD_STATE_AUTO);
1789 	} else if (auto_discovered != NULL)
1790 		*auto_discovered = B_FALSE;
1791 
1792 	return (trusted_domains);
1793 }
1794 
1795 
1796 static ad_item_t *
1797 validate_DomainsInForest(ad_disc_t ctx)
1798 {
1799 	ad_item_t *global_catalog_item;
1800 	LDAP *ld = NULL;
1801 	ad_disc_domainsinforest_t *domains_in_forest;
1802 
1803 	if (is_fixed(&ctx->domains_in_forest))
1804 		return (&ctx->domains_in_forest);
1805 
1806 	global_catalog_item = validate_GlobalCatalog(ctx, AD_DISC_GLOBAL);
1807 	if (global_catalog_item == NULL)
1808 		return (NULL);
1809 
1810 	if (!is_valid(&ctx->domains_in_forest) ||
1811 	    is_changed(&ctx->domains_in_forest, PARAM1, global_catalog_item)) {
1812 
1813 		domains_in_forest = ldap_lookup_domains_in_forest(
1814 		    &ld, global_catalog_item->value);
1815 
1816 		if (ld != NULL)
1817 			(void) ldap_unbind(ld);
1818 
1819 		if (domains_in_forest == NULL)
1820 			return (NULL);
1821 
1822 		update_item(&ctx->domains_in_forest, domains_in_forest,
1823 		    AD_STATE_AUTO, 0);
1824 		update_version(&ctx->domains_in_forest, PARAM1,
1825 		    global_catalog_item);
1826 	}
1827 	return (&ctx->domains_in_forest);
1828 }
1829 
1830 
1831 ad_disc_domainsinforest_t *
1832 ad_disc_get_DomainsInForest(ad_disc_t ctx, boolean_t *auto_discovered)
1833 {
1834 	ad_disc_domainsinforest_t *domains_in_forest = NULL;
1835 	ad_item_t *domains_in_forest_item;
1836 
1837 	domains_in_forest_item = validate_DomainsInForest(ctx);
1838 
1839 	if (domains_in_forest_item != NULL) {
1840 		domains_in_forest = df_dup(domains_in_forest_item->value);
1841 		if (auto_discovered != NULL)
1842 			*auto_discovered =
1843 			    (domains_in_forest_item->state == AD_STATE_AUTO);
1844 	} else if (auto_discovered != NULL)
1845 		*auto_discovered = B_FALSE;
1846 
1847 	return (domains_in_forest);
1848 }
1849 
1850 
1851 
1852 
1853 int
1854 ad_disc_set_DomainName(ad_disc_t ctx, const char *domainName)
1855 {
1856 	char *domain_name = NULL;
1857 	if (domainName != NULL) {
1858 		domain_name = strdup(domainName);
1859 		if (domain_name == NULL)
1860 			return (-1);
1861 		update_item(&ctx->domain_name, domain_name,
1862 		    AD_STATE_FIXED, 0);
1863 	} else if (ctx->domain_name.state == AD_STATE_FIXED)
1864 		ctx->domain_name.state = AD_STATE_INVALID;
1865 	return (0);
1866 }
1867 
1868 
1869 int
1870 ad_disc_set_DomainController(ad_disc_t ctx,
1871 				const idmap_ad_disc_ds_t *domainController)
1872 {
1873 	idmap_ad_disc_ds_t *domain_controller = NULL;
1874 	if (domainController != NULL) {
1875 		domain_controller = ds_dup(domainController);
1876 		if (domain_controller == NULL)
1877 			return (-1);
1878 		update_item(&ctx->domain_controller, domain_controller,
1879 		    AD_STATE_FIXED, 0);
1880 	} else if (ctx->domain_controller.state == AD_STATE_FIXED)
1881 		ctx->domain_controller.state = AD_STATE_INVALID;
1882 	return (0);
1883 }
1884 
1885 
1886 int
1887 ad_disc_set_SiteName(ad_disc_t ctx, const char *siteName)
1888 {
1889 	char *site_name = NULL;
1890 	if (siteName != NULL) {
1891 		site_name = strdup(siteName);
1892 		if (site_name == NULL)
1893 			return (-1);
1894 		update_item(&ctx->site_name, site_name, AD_STATE_FIXED, 0);
1895 	} else if (ctx->site_name.state == AD_STATE_FIXED)
1896 		ctx->site_name.state = AD_STATE_INVALID;
1897 	return (0);
1898 }
1899 
1900 int
1901 ad_disc_set_ForestName(ad_disc_t ctx, const char *forestName)
1902 {
1903 	char *forest_name = NULL;
1904 	if (forestName != NULL) {
1905 		forest_name = strdup(forestName);
1906 		if (forest_name == NULL)
1907 			return (-1);
1908 		update_item(&ctx->forest_name, forest_name,
1909 		    AD_STATE_FIXED, 0);
1910 	} else if (ctx->forest_name.state == AD_STATE_FIXED)
1911 		ctx->forest_name.state = AD_STATE_INVALID;
1912 	return (0);
1913 }
1914 
1915 int
1916 ad_disc_set_GlobalCatalog(ad_disc_t ctx,
1917     const idmap_ad_disc_ds_t *globalCatalog)
1918 {
1919 	idmap_ad_disc_ds_t *global_catalog = NULL;
1920 	if (globalCatalog != NULL) {
1921 		global_catalog = ds_dup(globalCatalog);
1922 		if (global_catalog == NULL)
1923 			return (-1);
1924 		update_item(&ctx->global_catalog, global_catalog,
1925 		    AD_STATE_FIXED, 0);
1926 	} else if (ctx->global_catalog.state == AD_STATE_FIXED)
1927 		ctx->global_catalog.state = AD_STATE_INVALID;
1928 	return (0);
1929 }
1930 
1931 
1932 int
1933 ad_disc_unset(ad_disc_t ctx)
1934 {
1935 	if (ctx->domain_name.state == AD_STATE_FIXED)
1936 		ctx->domain_name.state =  AD_STATE_INVALID;
1937 
1938 	if (ctx->domain_controller.state == AD_STATE_FIXED)
1939 		ctx->domain_controller.state =  AD_STATE_INVALID;
1940 
1941 	if (ctx->site_name.state == AD_STATE_FIXED)
1942 		ctx->site_name.state =  AD_STATE_INVALID;
1943 
1944 	if (ctx->forest_name.state == AD_STATE_FIXED)
1945 		ctx->forest_name.state =  AD_STATE_INVALID;
1946 
1947 	if (ctx->global_catalog.state == AD_STATE_FIXED)
1948 		ctx->global_catalog.state =  AD_STATE_INVALID;
1949 
1950 	return (0);
1951 }
1952 
1953 /*
1954  * ad_disc_get_TTL
1955  *
1956  * This routines the time to live for AD
1957  * auto discovered items.
1958  *
1959  *	Returns:
1960  *		-1 if there are no TTL items
1961  *		0  if there are expired items
1962  *		else the number of seconds
1963  *
1964  * The MIN_GT_ZERO(x, y) macro return the lesser of x and y, provided it
1965  * is positive -- min() greater than zero.
1966  */
1967 #define	MIN_GT_ZERO(x, y) (((x) <= 0) ? (((y) <= 0) ? \
1968 		(-1) : (y)) : (((y) <= 0) ? (x) : (((x) > (y)) ? (y) : (x))))
1969 int
1970 ad_disc_get_TTL(ad_disc_t ctx)
1971 {
1972 	int ttl;
1973 
1974 	ttl = MIN_GT_ZERO(ctx->domain_controller.ttl, ctx->global_catalog.ttl);
1975 	ttl = MIN_GT_ZERO(ttl, ctx->site_domain_controller.ttl);
1976 	ttl = MIN_GT_ZERO(ttl, ctx->site_global_catalog.ttl);
1977 
1978 	if (ttl == -1)
1979 		return (-1);
1980 	ttl -= time(NULL);
1981 	if (ttl < 0)
1982 		return (0);
1983 	return (ttl);
1984 }
1985 
1986 boolean_t
1987 ad_disc_SubnetChanged(ad_disc_t ctx)
1988 {
1989 	ad_subnet_t *subnets;
1990 
1991 	if (ctx->subnets_changed || ctx->subnets == NULL)
1992 		return (B_TRUE);
1993 
1994 	if ((subnets = find_subnets()) != NULL) {
1995 		if (cmpsubnets(subnets, ctx->subnets) != 0)
1996 			ctx->subnets_changed = B_TRUE;
1997 		free(subnets);
1998 	}
1999 
2000 	return (ctx->subnets_changed);
2001 }
2002