3 * Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Bill Paul.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * $FreeBSD: src/usr.sbin/ypserv/yp_dblookup.c,v 1.25 2003/05/03 21:06:42 obrien Exp $
33 * $DragonFly: src/usr.sbin/ypserv/yp_dblookup.c,v 1.4 2004/12/18 22:48:15 swildner Exp $
46 #include <sys/param.h>
47 #include <rpcsvc/yp.h>
48 #include "yp_extern.h"
51 enum ypstat yp_errno
= YP_TRUE
;
53 #define PERM_SECURE (S_IRUSR|S_IWUSR)
58 2048 * 512, /* cachesize */
64 #include <sys/queue.h>
70 static int numdbs
= 0;
80 static TAILQ_HEAD(circlehead
, circleq_entry
) qhead
;
82 struct circleq_entry
{
84 TAILQ_ENTRY(circleq_entry
) links
;
88 * Initialize the circular queue.
97 * Dynamically allocate an entry for the circular queue.
98 * Return a NULL pointer on failure.
100 static struct circleq_entry
*
103 struct circleq_entry
*q
;
105 q
= (struct circleq_entry
*)malloc(sizeof(struct circleq_entry
));
107 yp_error("failed to malloc() circleq entry");
110 bzero((char *)q
, sizeof(struct circleq_entry
));
111 q
->dbptr
= (struct dbent
*)malloc(sizeof(struct dbent
));
112 if (q
->dbptr
== NULL
) {
113 yp_error("failed to malloc() circleq entry");
117 bzero((char *)q
->dbptr
, sizeof(struct dbent
));
123 * Free a previously allocated circular queue
127 yp_free_qent(struct circleq_entry
*q
)
130 * First, close the database. In theory, this is also
131 * supposed to free the resources allocated by the DB
132 * package, including the memory pointed to by q->dbptr->key.
133 * This means we don't have to free q->dbptr->key here.
136 q
->dbptr
->dbp
->close(q
->dbptr
->dbp
);
137 q
->dbptr
->dbp
= NULL
;
140 * Then free the database name, which was strdup()'ed.
142 free(q
->dbptr
->name
);
145 * Free the rest of the dbent struct.
151 * Free the circleq struct.
158 * Zorch a single entry in the dbent queue and release
159 * all its resources. (This always removes the last entry
165 struct circleq_entry
*qptr
;
167 qptr
= TAILQ_LAST(&qhead
, circlehead
);
168 TAILQ_REMOVE(&qhead
, qptr
, links
);
174 * Close all databases, erase all database names and empty the queue.
179 struct circleq_entry
*qptr
;
181 while (!TAILQ_EMPTY(&qhead
)) {
182 qptr
= TAILQ_FIRST(&qhead
); /* save this */
183 TAILQ_REMOVE(&qhead
, qptr
, links
);
189 static char *inter_string
= "YP_INTERDOMAIN";
190 static char *secure_string
= "YP_SECURE";
191 static int inter_sz
= sizeof("YP_INTERDOMAIN") - 1;
192 static int secure_sz
= sizeof("YP_SECURE") - 1;
197 DBT key
= { NULL
, 0 }, data
= { NULL
, 0 };
200 key
.data
= inter_string
;
203 if (!(dbp
->get
)(dbp
, &key
, &data
, 0))
204 flags
|= YP_INTERDOMAIN
;
206 key
.data
= secure_string
;
207 key
.size
= secure_sz
;
209 if (!(dbp
->get
)(dbp
, &key
, &data
, 0))
216 yp_testflag(char *map
, char *domain
, int flag
)
218 char buf
[MAXPATHLEN
+ 2];
219 struct circleq_entry
*qptr
;
221 if (map
== NULL
|| domain
== NULL
)
228 TAILQ_FOREACH(qptr
, &qhead
, links
) {
229 if (!strcmp(qptr
->dbptr
->name
, buf
)) {
230 if (qptr
->dbptr
->flags
& flag
)
237 if (yp_open_db_cache(domain
, map
, NULL
, 0) == NULL
)
240 if (TAILQ_FIRST(&qhead
)->dbptr
->flags
& flag
)
247 * Add a DB handle and database name to the cache. We only maintain
248 * fixed number of entries in the cache, so if we're asked to store
249 * a new entry when all our slots are already filled, we have to kick
250 * out the entry in the last slot to make room.
253 yp_cache_db(DB
*dbp
, char *name
, int size
)
255 struct circleq_entry
*qptr
;
257 if (numdbs
== MAXDBS
) {
259 yp_error("queue overflow -- releasing last slot");
264 * Allocate a new queue entry.
267 if ((qptr
= yp_malloc_qent()) == NULL
) {
268 yp_error("failed to allocate a new cache entry");
272 qptr
->dbptr
->dbp
= dbp
;
273 qptr
->dbptr
->name
= strdup(name
);
274 qptr
->dbptr
->size
= size
;
275 qptr
->dbptr
->key
= NULL
;
277 qptr
->dbptr
->flags
= yp_setflags(dbp
);
279 TAILQ_INSERT_HEAD(&qhead
, qptr
, links
);
286 * Search the list for a database matching 'name.' If we find it,
287 * move it to the head of the list and return its DB handle. If
288 * not, just fail: yp_open_db_cache() will subsequently try to open
289 * the database itself and call yp_cache_db() to add it to the
292 * The search works like this:
294 * - The caller specifies the name of a database to locate. We try to
295 * find an entry in our queue with a matching name.
297 * - If the caller doesn't specify a key or size, we assume that the
298 * first entry that we encounter with a matching name is returned.
299 * This will result in matches regardless of the key/size values
300 * stored in the queue entry.
302 * - If the caller also specifies a key and length, we check to see
303 * if the key and length saved in the queue entry also matches.
304 * This lets us return a DB handle that's already positioned at the
305 * correct location within a database.
307 * - Once we have a match, it gets migrated to the top of the queue
308 * so that it will be easier to find if another request for
309 * the same database comes in later.
312 yp_find_db(const char *name
, const char *key
, const int size
)
314 struct circleq_entry
*qptr
;
316 TAILQ_FOREACH(qptr
, &qhead
, links
) {
317 if (!strcmp(qptr
->dbptr
->name
, name
)) {
319 if (size
!= qptr
->dbptr
->size
||
320 strncmp(qptr
->dbptr
->key
, key
, size
))
323 if (qptr
->dbptr
->size
)
326 if (qptr
!= TAILQ_FIRST(&qhead
)) {
327 TAILQ_REMOVE(&qhead
, qptr
, links
);
328 TAILQ_INSERT_HEAD(&qhead
, qptr
, links
);
330 return(qptr
->dbptr
->dbp
);
338 * Open a DB database and cache the handle for later use. We first
339 * check the cache to see if the required database is already open.
340 * If so, we fetch the handle from the cache. If not, we try to open
341 * the database and save the handle in the cache for later use.
344 yp_open_db_cache(const char *domain
, const char *map
, const char *key
,
348 char buf
[MAXPATHLEN
+ 2];
350 snprintf(buf, sizeof(buf), "%s/%s", domain, map);
358 if ((dbp
= yp_find_db(buf
, key
, size
)) != NULL
) {
361 if ((dbp
= yp_open_db(domain
, map
)) != NULL
) {
362 if (yp_cache_db(dbp
, buf
, size
)) {
375 * Open a DB database.
378 yp_open_db(const char *domain
, const char *map
)
381 char buf
[MAXPATHLEN
+ 2];
385 if (map
[0] == '.' || strchr(map
, '/')) {
386 yp_errno
= YP_BADARGS
;
391 if (yp_validdomain(domain
)) {
396 snprintf(buf
, sizeof(buf
), "%s/%s/%s", yp_dir
, domain
, map
);
401 dbp
= dbopen(buf
,O_RDONLY
, PERM_SECURE
, DB_HASH
, NULL
);
408 * We ran out of file descriptors. Nuke an
409 * open one and try again.
411 yp_error("ran out of file descriptors");
432 * Database access routines.
434 * - yp_get_record(): retrieve an arbitrary key/data pair given one key
437 * - yp_first_record(): retrieve first key/data base in a database.
439 * - yp_next_record(): retrieve key/data pair that sequentially follows
440 * the supplied key value in the database.
445 yp_get_record(DB
*dbp
, const DBT
*key
, DBT
*data
, int allow
)
448 yp_get_record(const char *domain
, const char *map
, const DBT
*key
,
449 DBT
*data
, int allow
)
457 static unsigned char buf
[YPMAXRECORD
];
461 yp_error("looking up key [%.*s]",
462 (int)key
->size
, (char *)key
->data
);
465 * Avoid passing back magic "YP_*" entries unless
466 * the caller specifically requested them by setting
469 if (!allow
&& !strncmp(key
->data
, "YP_", 3))
473 if ((dbp
= yp_open_db(domain
, map
)) == NULL
) {
478 if ((rval
= (dbp
->get
)(dbp
, key
, data
, 0)) != 0) {
480 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
491 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
492 (int)key
->size
, (char *)key
->data
,
493 (int)data
->size
, (char *)data
->data
);
496 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
497 TAILQ_FIRST(&qhead
)->dbptr
->key
= "";
498 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
501 bcopy(data
->data
, &buf
, data
->size
);
510 yp_first_record(const DB
*dbp
, DBT
*key
, DBT
*data
, int allow
)
514 static unsigned char buf
[YPMAXRECORD
];
518 yp_error("retrieving first key in map");
520 if ((rval
= (dbp
->seq
)(dbp
,key
,data
,R_FIRST
)) != 0) {
522 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
530 /* Avoid passing back magic "YP_*" records. */
531 while (!strncmp(key
->data
, "YP_", 3) && !allow
) {
532 if ((rval
= (dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) != 0) {
534 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
544 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
545 (int)key
->size
, (char *)key
->data
,
546 (int)data
->size
, (char *)data
->data
);
549 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
550 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
551 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
554 bcopy(data
->data
, &buf
, data
->size
);
562 yp_next_record(const DB
*dbp
, DBT
*key
, DBT
*data
, int all
, int allow
)
564 static DBT lkey
= { NULL
, 0 };
565 static DBT ldata
= { NULL
, 0 };
568 static unsigned char keybuf
[YPMAXRECORD
];
569 static unsigned char datbuf
[YPMAXRECORD
];
572 if (key
== NULL
|| !key
->size
|| key
->data
== NULL
) {
573 rval
= yp_first_record(dbp
,key
,data
,allow
);
574 if (rval
== YP_NOKEY
)
578 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
579 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
586 yp_error("retrieving next key, previous was: [%.*s]",
587 (int)key
->size
, (char *)key
->data
);
591 if (TAILQ_FIRST(&qhead
)->dbptr
->key
== NULL
) {
593 (dbp
->seq
)(dbp
,&lkey
,&ldata
,R_FIRST
);
594 while (key
->size
!= lkey
.size
||
595 strncmp(key
->data
, lkey
.data
,
597 if ((dbp
->seq
)(dbp
,&lkey
,&ldata
,R_NEXT
)) {
599 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
609 if ((dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) {
611 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
616 /* Avoid passing back magic "YP_*" records. */
617 while (!strncmp(key
->data
, "YP_", 3) && !allow
)
618 if ((dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) {
620 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
626 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
627 (int)key
->size
, (char *)key
->data
,
628 (int)data
->size
, (char *)data
->data
);
631 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
632 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
633 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
636 bcopy(key
->data
, &keybuf
, key
->size
);
638 lkey
.size
= key
->size
;
639 bcopy(data
->data
, &datbuf
, data
->size
);
640 data
->data
= &datbuf
;
648 * Database glue functions.
651 static DB
*yp_currmap_db
= NULL
;
652 static int yp_allow_db
= 0;
655 yp_select_map(char *map
, char *domain
, keydat
*key
, int allow
)
658 yp_currmap_db
= yp_open_db_cache(domain
, map
, NULL
, 0);
660 yp_currmap_db
= yp_open_db_cache(domain
, map
,
669 yp_getbykey(keydat
*key
, valdat
*val
)
671 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
674 db_key
.data
= key
->keydat_val
;
675 db_key
.size
= key
->keydat_len
;
677 rval
= yp_get_record(yp_currmap_db
,
678 &db_key
, &db_val
, yp_allow_db
);
680 if (rval
== YP_TRUE
) {
681 val
->valdat_val
= db_val
.data
;
682 val
->valdat_len
= db_val
.size
;
689 yp_firstbykey(keydat
*key
, valdat
*val
)
691 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
694 rval
= yp_first_record(yp_currmap_db
, &db_key
, &db_val
, yp_allow_db
);
696 if (rval
== YP_TRUE
) {
697 key
->keydat_val
= db_key
.data
;
698 key
->keydat_len
= db_key
.size
;
699 val
->valdat_val
= db_val
.data
;
700 val
->valdat_len
= db_val
.size
;
707 yp_nextbykey(keydat
*key
, valdat
*val
)
709 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
712 db_key
.data
= key
->keydat_val
;
713 db_key
.size
= key
->keydat_len
;
715 rval
= yp_next_record(yp_currmap_db
, &db_key
, &db_val
, 0, yp_allow_db
);
717 if (rval
== YP_TRUE
) {
718 key
->keydat_val
= db_key
.data
;
719 key
->keydat_len
= db_key
.size
;
720 val
->valdat_val
= db_val
.data
;
721 val
->valdat_len
= db_val
.size
;