2 Unix SMB/CIFS implementation.
4 Copyright (C) Gerald (Jerry) Carter 2006.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 /* AIX resolv.h uses 'class' in struct ns_rr */
31 /* resolver headers */
33 #include <sys/types.h>
34 #include <netinet/in.h>
35 #include <arpa/nameser.h>
39 #define MAX_DNS_PACKET_SIZE 0xffff
41 #ifdef NS_HFIXEDSZ /* Bind 8/9 interface */
42 #if !defined(C_IN) /* AIX 5.3 already defines C_IN */
45 #if !defined(T_A) /* AIX 5.3 already defines T_A */
48 # define T_SRV ns_t_srv
49 #if !defined(T_NS) /* AIX 5.3 already defines T_NS */
54 # define NS_HFIXEDSZ HFIXEDSZ
56 # define NS_HFIXEDSZ sizeof(HEADER)
57 # endif /* HFIXEDSZ */
59 # define NS_PACKETSZ PACKETSZ
60 # else /* 512 is usually the default */
61 # define NS_PACKETSZ 512
62 # endif /* PACKETSZ */
66 /*********************************************************************
67 *********************************************************************/
69 static BOOL ads_dns_parse_query( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
70 uint8 **ptr, struct dns_query *q )
78 if ( !start || !end || !q || !*ptr)
81 /* See RFC 1035 for details. If this fails, then return. */
83 namelen = dn_expand( start, end, p, hostname, sizeof(hostname) );
88 q->hostname = talloc_strdup( ctx, hostname );
90 /* check that we have space remaining */
92 if ( PTR_DIFF(p+4, end) > 0 )
95 q->type = RSVAL( p, 0 );
96 q->in_class = RSVAL( p, 2 );
104 /*********************************************************************
105 *********************************************************************/
107 static BOOL ads_dns_parse_rr( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
108 uint8 **ptr, struct dns_rr *rr )
114 if ( !start || !end || !rr || !*ptr)
118 /* pull the name from the answer */
120 namelen = dn_expand( start, end, p, hostname, sizeof(hostname) );
125 rr->hostname = talloc_strdup( ctx, hostname );
127 /* check that we have space remaining */
129 if ( PTR_DIFF(p+10, end) > 0 )
132 /* pull some values and then skip onto the string */
134 rr->type = RSVAL(p, 0);
135 rr->in_class = RSVAL(p, 2);
136 rr->ttl = RIVAL(p, 4);
137 rr->rdatalen = RSVAL(p, 8);
141 /* sanity check the available space */
143 if ( PTR_DIFF(p+rr->rdatalen, end ) > 0 ) {
148 /* save a point to the rdata for this section */
158 /*********************************************************************
159 *********************************************************************/
161 static BOOL ads_dns_parse_rr_srv( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
162 uint8 **ptr, struct dns_rr_srv *srv )
169 if ( !start || !end || !srv || !*ptr)
172 /* Parse the RR entry. Coming out of the this, ptr is at the beginning
173 of the next record */
175 if ( !ads_dns_parse_rr( ctx, start, end, ptr, &rr ) ) {
176 DEBUG(1,("ads_dns_parse_rr_srv: Failed to parse RR record\n"));
180 if ( rr.type != T_SRV ) {
181 DEBUG(1,("ads_dns_parse_rr_srv: Bad answer type (%d)\n", rr.type));
187 srv->priority = RSVAL(p, 0);
188 srv->weight = RSVAL(p, 2);
189 srv->port = RSVAL(p, 4);
193 namelen = dn_expand( start, end, p, dcname, sizeof(dcname) );
195 DEBUG(1,("ads_dns_parse_rr_srv: Failed to uncompress name!\n"));
198 srv->hostname = talloc_strdup( ctx, dcname );
203 /*********************************************************************
204 *********************************************************************/
206 static BOOL ads_dns_parse_rr_ns( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
207 uint8 **ptr, struct dns_rr_ns *nsrec )
214 if ( !start || !end || !nsrec || !*ptr)
217 /* Parse the RR entry. Coming out of the this, ptr is at the beginning
218 of the next record */
220 if ( !ads_dns_parse_rr( ctx, start, end, ptr, &rr ) ) {
221 DEBUG(1,("ads_dns_parse_rr_ns: Failed to parse RR record\n"));
225 if ( rr.type != T_NS ) {
226 DEBUG(1,("ads_dns_parse_rr_ns: Bad answer type (%d)\n", rr.type));
232 /* ame server hostname */
234 namelen = dn_expand( start, end, p, nsname, sizeof(nsname) );
236 DEBUG(1,("ads_dns_parse_rr_ns: Failed to uncompress name!\n"));
239 nsrec->hostname = talloc_strdup( ctx, nsname );
244 /*********************************************************************
245 Sort SRV record list based on weight and priority. See RFC 2782.
246 *********************************************************************/
248 static int dnssrvcmp( struct dns_rr_srv *a, struct dns_rr_srv *b )
250 if ( a->priority == b->priority ) {
252 /* randomize entries with an equal weight and priority */
253 if ( a->weight == b->weight )
256 /* higher weights should be sorted lower */
257 if ( a->weight > b->weight )
263 if ( a->priority < b->priority )
269 /*********************************************************************
270 Simple wrapper for a DNS query
271 *********************************************************************/
273 static NTSTATUS dns_send_req( TALLOC_CTX *ctx, const char *name, int q_type,
274 uint8 **buf, int *resp_length )
276 uint8 *buffer = NULL;
278 int resp_len = NS_PACKETSZ;
282 TALLOC_FREE( buffer );
284 buf_len = resp_len * sizeof(uint8);
286 if ( (buffer = TALLOC_ARRAY(ctx, uint8, buf_len)) == NULL ) {
287 DEBUG(0,("ads_dns_lookup_srv: talloc() failed!\n"));
288 return NT_STATUS_NO_MEMORY;
291 if ( (resp_len = res_query(name, C_IN, q_type, buffer, buf_len)) < 0 ) {
292 DEBUG(3,("ads_dns_lookup_srv: Failed to resolve %s (%s)\n", name, strerror(errno)));
293 TALLOC_FREE( buffer );
294 if (errno == ETIMEDOUT) {
295 return NT_STATUS_IO_TIMEOUT;
297 if (errno == ECONNREFUSED) {
298 return NT_STATUS_CONNECTION_REFUSED;
300 return NT_STATUS_UNSUCCESSFUL;
302 } while ( buf_len < resp_len && resp_len < MAX_DNS_PACKET_SIZE );
305 *resp_length = resp_len;
310 /*********************************************************************
311 Simple wrapper for a DNS SRV query
312 *********************************************************************/
314 static NTSTATUS ads_dns_lookup_srv( TALLOC_CTX *ctx, const char *name, struct dns_rr_srv **dclist, int *numdcs )
316 uint8 *buffer = NULL;
318 struct dns_rr_srv *dcs = NULL;
319 int query_count, answer_count, auth_count, additional_count;
325 if ( !ctx || !name || !dclist ) {
326 return NT_STATUS_INVALID_PARAMETER;
329 /* Send the request. May have to loop several times in case
332 status = dns_send_req( ctx, name, T_SRV, &buffer, &resp_len );
333 if ( !NT_STATUS_IS_OK(status) ) {
334 DEBUG(3,("ads_dns_lookup_srv: Failed to send DNS query (%s)\n",
340 /* For some insane reason, the ns_initparse() et. al. routines are only
341 available in libresolv.a, and not the shared lib. Who knows why....
342 So we have to parse the DNS reply ourselves */
344 /* Pull the answer RR's count from the header. Use the NMB ordering macros */
346 query_count = RSVAL( p, 4 );
347 answer_count = RSVAL( p, 6 );
348 auth_count = RSVAL( p, 8 );
349 additional_count = RSVAL( p, 10 );
351 DEBUG(4,("ads_dns_lookup_srv: %d records returned in the answer section.\n",
354 if ( (dcs = TALLOC_ZERO_ARRAY(ctx, struct dns_rr_srv, answer_count)) == NULL ) {
355 DEBUG(0,("ads_dns_lookup_srv: talloc() failure for %d char*'s\n",
357 return NT_STATUS_NO_MEMORY;
360 /* now skip the header */
364 /* parse the query section */
366 for ( rrnum=0; rrnum<query_count; rrnum++ ) {
369 if ( !ads_dns_parse_query( ctx, buffer, buffer+resp_len, &p, &q ) ) {
370 DEBUG(1,("ads_dns_lookup_srv: Failed to parse query record!\n"));
371 return NT_STATUS_UNSUCCESSFUL;
375 /* now we are at the answer section */
377 for ( rrnum=0; rrnum<answer_count; rrnum++ ) {
378 if ( !ads_dns_parse_rr_srv( ctx, buffer, buffer+resp_len, &p, &dcs[rrnum] ) ) {
379 DEBUG(1,("ads_dns_lookup_srv: Failed to parse answer record!\n"));
380 return NT_STATUS_UNSUCCESSFUL;
385 /* Parse the authority section */
386 /* just skip these for now */
388 for ( rrnum=0; rrnum<auth_count; rrnum++ ) {
391 if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
392 DEBUG(1,("ads_dns_lookup_srv: Failed to parse authority record!\n"));
393 return NT_STATUS_UNSUCCESSFUL;
397 /* Parse the additional records section */
399 for ( rrnum=0; rrnum<additional_count; rrnum++ ) {
403 if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
404 DEBUG(1,("ads_dns_lookup_srv: Failed to parse additional records section!\n"));
405 return NT_STATUS_UNSUCCESSFUL;
408 /* only interested in A records as a shortcut for having to come
409 back later and lookup the name. For multi-homed hosts, the
410 number of additional records and exceed the number of answer
414 if ( (rr.type != T_A) || (rr.rdatalen != 4) )
417 for ( i=0; i<idx; i++ ) {
418 if ( strcmp( rr.hostname, dcs[i].hostname ) == 0 ) {
419 int num_ips = dcs[i].num_ips;
421 struct in_addr *tmp_ips;
423 /* allocate new memory */
425 if ( dcs[i].num_ips == 0 ) {
426 if ( (dcs[i].ips = TALLOC_ARRAY( dcs,
427 struct in_addr, 1 )) == NULL )
429 return NT_STATUS_NO_MEMORY;
432 if ( (tmp_ips = TALLOC_REALLOC_ARRAY( dcs, dcs[i].ips,
433 struct in_addr, dcs[i].num_ips+1)) == NULL )
435 return NT_STATUS_NO_MEMORY;
438 dcs[i].ips = tmp_ips;
442 /* copy the new IP address */
444 buf = (uint8*)&dcs[i].ips[num_ips].s_addr;
445 memcpy( buf, rr.rdata, 4 );
450 qsort( dcs, idx, sizeof(struct dns_rr_srv), QSORT_CAST dnssrvcmp );
458 /*********************************************************************
459 Simple wrapper for a DNS NS query
460 *********************************************************************/
462 NTSTATUS ads_dns_lookup_ns( TALLOC_CTX *ctx, const char *dnsdomain, struct dns_rr_ns **nslist, int *numns )
464 uint8 *buffer = NULL;
466 struct dns_rr_ns *nsarray = NULL;
467 int query_count, answer_count, auth_count, additional_count;
473 if ( !ctx || !dnsdomain || !nslist ) {
474 return NT_STATUS_INVALID_PARAMETER;
477 /* Send the request. May have to loop several times in case
480 status = dns_send_req( ctx, dnsdomain, T_NS, &buffer, &resp_len );
481 if ( !NT_STATUS_IS_OK(status) ) {
482 DEBUG(3,("ads_dns_lookup_ns: Failed to send DNS query (%s)\n",
488 /* For some insane reason, the ns_initparse() et. al. routines are only
489 available in libresolv.a, and not the shared lib. Who knows why....
490 So we have to parse the DNS reply ourselves */
492 /* Pull the answer RR's count from the header. Use the NMB ordering macros */
494 query_count = RSVAL( p, 4 );
495 answer_count = RSVAL( p, 6 );
496 auth_count = RSVAL( p, 8 );
497 additional_count = RSVAL( p, 10 );
499 DEBUG(4,("ads_dns_lookup_ns: %d records returned in the answer section.\n",
502 if ( (nsarray = TALLOC_ARRAY(ctx, struct dns_rr_ns, answer_count)) == NULL ) {
503 DEBUG(0,("ads_dns_lookup_ns: talloc() failure for %d char*'s\n",
505 return NT_STATUS_NO_MEMORY;
508 /* now skip the header */
512 /* parse the query section */
514 for ( rrnum=0; rrnum<query_count; rrnum++ ) {
517 if ( !ads_dns_parse_query( ctx, buffer, buffer+resp_len, &p, &q ) ) {
518 DEBUG(1,("ads_dns_lookup_ns: Failed to parse query record!\n"));
519 return NT_STATUS_UNSUCCESSFUL;
523 /* now we are at the answer section */
525 for ( rrnum=0; rrnum<answer_count; rrnum++ ) {
526 if ( !ads_dns_parse_rr_ns( ctx, buffer, buffer+resp_len, &p, &nsarray[rrnum] ) ) {
527 DEBUG(1,("ads_dns_lookup_ns: Failed to parse answer record!\n"));
528 return NT_STATUS_UNSUCCESSFUL;
533 /* Parse the authority section */
534 /* just skip these for now */
536 for ( rrnum=0; rrnum<auth_count; rrnum++ ) {
539 if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
540 DEBUG(1,("ads_dns_lookup_ns: Failed to parse authority record!\n"));
541 return NT_STATUS_UNSUCCESSFUL;
545 /* Parse the additional records section */
547 for ( rrnum=0; rrnum<additional_count; rrnum++ ) {
551 if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
552 DEBUG(1,("ads_dns_lookup_ns: Failed to parse additional records section!\n"));
553 return NT_STATUS_UNSUCCESSFUL;
556 /* only interested in A records as a shortcut for having to come
557 back later and lookup the name */
559 if ( (rr.type != T_A) || (rr.rdatalen != 4) )
562 for ( i=0; i<idx; i++ ) {
563 if ( strcmp( rr.hostname, nsarray[i].hostname ) == 0 ) {
564 uint8 *buf = (uint8*)&nsarray[i].ip.s_addr;
565 memcpy( buf, rr.rdata, 4 );
576 /****************************************************************************
577 Store and fetch the AD client sitename.
578 ****************************************************************************/
580 #define SITENAME_KEY "AD_SITENAME"
582 /****************************************************************************
583 Store the AD client sitename.
584 We store indefinately as every new CLDAP query will re-write this.
585 If the sitename is "Default-First-Site-Name" we don't store it
586 as this isn't a valid DNS name.
587 ****************************************************************************/
589 BOOL sitename_store(const char *sitename)
594 if (!gencache_init()) {
598 if (!sitename || (sitename && !*sitename)) {
599 DEBUG(5,("sitename_store: deleting empty sitename!\n"));
600 return gencache_del(SITENAME_KEY);
603 expire = get_time_t_max(); /* Store indefinately. */
605 DEBUG(10,("sitename_store: sitename = [%s], expire = [%u]\n",
606 sitename, (unsigned int)expire ));
608 ret = gencache_set( SITENAME_KEY, sitename, expire );
612 /****************************************************************************
613 Fetch the AD client sitename.
615 ****************************************************************************/
617 char *sitename_fetch(void)
619 char *sitename = NULL;
623 if (!gencache_init()) {
627 ret = gencache_get( SITENAME_KEY, &sitename, &timeout );
629 DEBUG(5,("sitename_fetch: No stored sitename\n"));
631 DEBUG(5,("sitename_fetch: Returning sitename \"%s\"\n",
637 /****************************************************************************
638 Did the sitename change ?
639 ****************************************************************************/
641 BOOL stored_sitename_changed(const char *sitename)
644 char *new_sitename = sitename_fetch();
646 if (sitename && new_sitename && !strequal(sitename, new_sitename)) {
648 } else if ((sitename && !new_sitename) ||
649 (!sitename && new_sitename)) {
652 SAFE_FREE(new_sitename);
656 /********************************************************************
657 Query with optional sitename.
658 ********************************************************************/
660 NTSTATUS ads_dns_query_internal(TALLOC_CTX *ctx,
661 const char *servicename,
663 const char *sitename,
664 struct dns_rr_srv **dclist,
669 name = talloc_asprintf(ctx, "%s._tcp.%s._sites.dc._msdcs.%s",
670 servicename, sitename, realm );
672 name = talloc_asprintf(ctx, "%s._tcp.dc._msdcs.%s",
673 servicename, realm );
676 return NT_STATUS_NO_MEMORY;
678 return ads_dns_lookup_srv( ctx, name, dclist, numdcs );
681 /********************************************************************
683 ********************************************************************/
685 NTSTATUS ads_dns_query_dcs(TALLOC_CTX *ctx,
687 const char *sitename,
688 struct dns_rr_srv **dclist,
693 status = ads_dns_query_internal(ctx, "_ldap", realm, sitename,
696 if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT) ||
697 NT_STATUS_EQUAL(status, NT_STATUS_CONNECTION_REFUSED)) {
701 if (sitename && !NT_STATUS_IS_OK(status)) {
702 /* Sitename DNS query may have failed. Try without. */
703 status = ads_dns_query_internal(ctx, "_ldap", realm, NULL,
709 /********************************************************************
711 Even if our underlying kerberos libraries are UDP only, this
712 is pretty safe as it's unlikely that a KDC supports TCP and not UDP.
713 ********************************************************************/
715 NTSTATUS ads_dns_query_kdcs(TALLOC_CTX *ctx,
717 const char *sitename,
718 struct dns_rr_srv **dclist,
723 status = ads_dns_query_internal(ctx, "_kerberos", realm, sitename,
726 if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT) ||
727 NT_STATUS_EQUAL(status, NT_STATUS_CONNECTION_REFUSED)) {
731 if (sitename && !NT_STATUS_IS_OK(status)) {
732 /* Sitename DNS query may have failed. Try without. */
733 status = ads_dns_query_internal(ctx, "_kerberos", realm, NULL,