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 $
45 #include <sys/param.h>
46 #include <rpcsvc/yp.h>
47 #include "yp_extern.h"
50 enum ypstat yp_errno
= YP_TRUE
;
52 #define PERM_SECURE (S_IRUSR|S_IWUSR)
57 2048 * 512, /* cachesize */
63 #include <sys/queue.h>
69 static int numdbs
= 0;
79 static TAILQ_HEAD(circlehead
, circleq_entry
) qhead
;
81 struct circleq_entry
{
83 TAILQ_ENTRY(circleq_entry
) links
;
87 * Initialize the circular queue.
96 * Dynamically allocate an entry for the circular queue.
97 * Return a NULL pointer on failure.
99 static struct circleq_entry
*
102 struct circleq_entry
*q
;
104 q
= (struct circleq_entry
*)malloc(sizeof(struct circleq_entry
));
106 yp_error("failed to malloc() circleq entry");
109 bzero((char *)q
, sizeof(struct circleq_entry
));
110 q
->dbptr
= (struct dbent
*)malloc(sizeof(struct dbent
));
111 if (q
->dbptr
== NULL
) {
112 yp_error("failed to malloc() circleq entry");
116 bzero((char *)q
->dbptr
, sizeof(struct dbent
));
122 * Free a previously allocated circular queue
126 yp_free_qent(struct circleq_entry
*q
)
129 * First, close the database. In theory, this is also
130 * supposed to free the resources allocated by the DB
131 * package, including the memory pointed to by q->dbptr->key.
132 * This means we don't have to free q->dbptr->key here.
135 q
->dbptr
->dbp
->close(q
->dbptr
->dbp
);
136 q
->dbptr
->dbp
= NULL
;
139 * Then free the database name, which was strdup()'ed.
141 free(q
->dbptr
->name
);
144 * Free the rest of the dbent struct.
150 * Free the circleq struct.
157 * Zorch a single entry in the dbent queue and release
158 * all its resources. (This always removes the last entry
164 struct circleq_entry
*qptr
;
166 qptr
= TAILQ_LAST(&qhead
, circlehead
);
167 TAILQ_REMOVE(&qhead
, qptr
, links
);
173 * Close all databases, erase all database names and empty the queue.
178 struct circleq_entry
*qptr
;
180 while (!TAILQ_EMPTY(&qhead
)) {
181 qptr
= TAILQ_FIRST(&qhead
); /* save this */
182 TAILQ_REMOVE(&qhead
, qptr
, links
);
188 static char *inter_string
= "YP_INTERDOMAIN";
189 static char *secure_string
= "YP_SECURE";
190 static int inter_sz
= sizeof("YP_INTERDOMAIN") - 1;
191 static int secure_sz
= sizeof("YP_SECURE") - 1;
196 DBT key
= { NULL
, 0 }, data
= { NULL
, 0 };
199 key
.data
= inter_string
;
202 if (!(dbp
->get
)(dbp
, &key
, &data
, 0))
203 flags
|= YP_INTERDOMAIN
;
205 key
.data
= secure_string
;
206 key
.size
= secure_sz
;
208 if (!(dbp
->get
)(dbp
, &key
, &data
, 0))
215 yp_testflag(char *map
, char *domain
, int flag
)
217 char buf
[MAXPATHLEN
+ 2];
218 struct circleq_entry
*qptr
;
220 if (map
== NULL
|| domain
== NULL
)
227 TAILQ_FOREACH(qptr
, &qhead
, links
) {
228 if (!strcmp(qptr
->dbptr
->name
, buf
)) {
229 if (qptr
->dbptr
->flags
& flag
)
236 if (yp_open_db_cache(domain
, map
, NULL
, 0) == NULL
)
239 if (TAILQ_FIRST(&qhead
)->dbptr
->flags
& flag
)
246 * Add a DB handle and database name to the cache. We only maintain
247 * fixed number of entries in the cache, so if we're asked to store
248 * a new entry when all our slots are already filled, we have to kick
249 * out the entry in the last slot to make room.
252 yp_cache_db(DB
*dbp
, char *name
, int size
)
254 struct circleq_entry
*qptr
;
256 if (numdbs
== MAXDBS
) {
258 yp_error("queue overflow -- releasing last slot");
263 * Allocate a new queue entry.
266 if ((qptr
= yp_malloc_qent()) == NULL
) {
267 yp_error("failed to allocate a new cache entry");
271 qptr
->dbptr
->dbp
= dbp
;
272 qptr
->dbptr
->name
= strdup(name
);
273 qptr
->dbptr
->size
= size
;
274 qptr
->dbptr
->key
= NULL
;
276 qptr
->dbptr
->flags
= yp_setflags(dbp
);
278 TAILQ_INSERT_HEAD(&qhead
, qptr
, links
);
285 * Search the list for a database matching 'name.' If we find it,
286 * move it to the head of the list and return its DB handle. If
287 * not, just fail: yp_open_db_cache() will subsequently try to open
288 * the database itself and call yp_cache_db() to add it to the
291 * The search works like this:
293 * - The caller specifies the name of a database to locate. We try to
294 * find an entry in our queue with a matching name.
296 * - If the caller doesn't specify a key or size, we assume that the
297 * first entry that we encounter with a matching name is returned.
298 * This will result in matches regardless of the key/size values
299 * stored in the queue entry.
301 * - If the caller also specifies a key and length, we check to see
302 * if the key and length saved in the queue entry also matches.
303 * This lets us return a DB handle that's already positioned at the
304 * correct location within a database.
306 * - Once we have a match, it gets migrated to the top of the queue
307 * so that it will be easier to find if another request for
308 * the same database comes in later.
311 yp_find_db(const char *name
, const char *key
, const int size
)
313 struct circleq_entry
*qptr
;
315 TAILQ_FOREACH(qptr
, &qhead
, links
) {
316 if (!strcmp(qptr
->dbptr
->name
, name
)) {
318 if (size
!= qptr
->dbptr
->size
||
319 strncmp(qptr
->dbptr
->key
, key
, size
))
322 if (qptr
->dbptr
->size
)
325 if (qptr
!= TAILQ_FIRST(&qhead
)) {
326 TAILQ_REMOVE(&qhead
, qptr
, links
);
327 TAILQ_INSERT_HEAD(&qhead
, qptr
, links
);
329 return(qptr
->dbptr
->dbp
);
337 * Open a DB database and cache the handle for later use. We first
338 * check the cache to see if the required database is already open.
339 * If so, we fetch the handle from the cache. If not, we try to open
340 * the database and save the handle in the cache for later use.
343 yp_open_db_cache(const char *domain
, const char *map
, const char *key
,
347 char buf
[MAXPATHLEN
+ 2];
349 snprintf(buf, sizeof(buf), "%s/%s", domain, map);
357 if ((dbp
= yp_find_db(buf
, key
, size
)) != NULL
) {
360 if ((dbp
= yp_open_db(domain
, map
)) != NULL
) {
361 if (yp_cache_db(dbp
, buf
, size
)) {
374 * Open a DB database.
377 yp_open_db(const char *domain
, const char *map
)
380 char buf
[MAXPATHLEN
+ 2];
384 if (map
[0] == '.' || strchr(map
, '/')) {
385 yp_errno
= YP_BADARGS
;
390 if (yp_validdomain(domain
)) {
395 snprintf(buf
, sizeof(buf
), "%s/%s/%s", yp_dir
, domain
, map
);
400 dbp
= dbopen(buf
,O_RDONLY
, PERM_SECURE
, DB_HASH
, NULL
);
407 * We ran out of file descriptors. Nuke an
408 * open one and try again.
410 yp_error("ran out of file descriptors");
431 * Database access routines.
433 * - yp_get_record(): retrieve an arbitrary key/data pair given one key
436 * - yp_first_record(): retrieve first key/data base in a database.
438 * - yp_next_record(): retrieve key/data pair that sequentially follows
439 * the supplied key value in the database.
444 yp_get_record(DB
*dbp
, const DBT
*key
, DBT
*data
, int allow
)
447 yp_get_record(const char *domain
, const char *map
, const DBT
*key
,
448 DBT
*data
, int allow
)
456 static unsigned char buf
[YPMAXRECORD
];
460 yp_error("looking up key [%.*s]",
461 (int)key
->size
, (char *)key
->data
);
464 * Avoid passing back magic "YP_*" entries unless
465 * the caller specifically requested them by setting
468 if (!allow
&& !strncmp(key
->data
, "YP_", 3))
472 if ((dbp
= yp_open_db(domain
, map
)) == NULL
) {
477 if ((rval
= (dbp
->get
)(dbp
, key
, data
, 0)) != 0) {
479 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
490 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
491 (int)key
->size
, (char *)key
->data
,
492 (int)data
->size
, (char *)data
->data
);
495 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
496 TAILQ_FIRST(&qhead
)->dbptr
->key
= "";
497 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
500 bcopy(data
->data
, &buf
, data
->size
);
509 yp_first_record(const DB
*dbp
, DBT
*key
, DBT
*data
, int allow
)
513 static unsigned char buf
[YPMAXRECORD
];
517 yp_error("retrieving first key in map");
519 if ((rval
= (dbp
->seq
)(dbp
,key
,data
,R_FIRST
)) != 0) {
521 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
529 /* Avoid passing back magic "YP_*" records. */
530 while (!strncmp(key
->data
, "YP_", 3) && !allow
) {
531 if ((rval
= (dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) != 0) {
533 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
543 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
544 (int)key
->size
, (char *)key
->data
,
545 (int)data
->size
, (char *)data
->data
);
548 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
549 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
550 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
553 bcopy(data
->data
, &buf
, data
->size
);
561 yp_next_record(const DB
*dbp
, DBT
*key
, DBT
*data
, int all
, int allow
)
563 static DBT lkey
= { NULL
, 0 };
564 static DBT ldata
= { NULL
, 0 };
567 static unsigned char keybuf
[YPMAXRECORD
];
568 static unsigned char datbuf
[YPMAXRECORD
];
571 if (key
== NULL
|| !key
->size
|| key
->data
== NULL
) {
572 rval
= yp_first_record(dbp
,key
,data
,allow
);
573 if (rval
== YP_NOKEY
)
577 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
578 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
585 yp_error("retrieving next key, previous was: [%.*s]",
586 (int)key
->size
, (char *)key
->data
);
590 if (TAILQ_FIRST(&qhead
)->dbptr
->key
== NULL
) {
592 (dbp
->seq
)(dbp
,&lkey
,&ldata
,R_FIRST
);
593 while (key
->size
!= lkey
.size
||
594 strncmp(key
->data
, lkey
.data
,
596 if ((dbp
->seq
)(dbp
,&lkey
,&ldata
,R_NEXT
)) {
598 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
608 if ((dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) {
610 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
615 /* Avoid passing back magic "YP_*" records. */
616 while (!strncmp(key
->data
, "YP_", 3) && !allow
)
617 if ((dbp
->seq
)(dbp
,key
,data
,R_NEXT
)) {
619 TAILQ_FIRST(&qhead
)->dbptr
->size
= 0;
625 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
626 (int)key
->size
, (char *)key
->data
,
627 (int)data
->size
, (char *)data
->data
);
630 if (TAILQ_FIRST(&qhead
)->dbptr
->size
) {
631 TAILQ_FIRST(&qhead
)->dbptr
->key
= key
->data
;
632 TAILQ_FIRST(&qhead
)->dbptr
->size
= key
->size
;
635 bcopy(key
->data
, &keybuf
, key
->size
);
637 lkey
.size
= key
->size
;
638 bcopy(data
->data
, &datbuf
, data
->size
);
639 data
->data
= &datbuf
;
647 * Database glue functions.
650 static DB
*yp_currmap_db
= NULL
;
651 static int yp_allow_db
= 0;
654 yp_select_map(char *map
, char *domain
, keydat
*key
, int allow
)
657 yp_currmap_db
= yp_open_db_cache(domain
, map
, NULL
, 0);
659 yp_currmap_db
= yp_open_db_cache(domain
, map
,
668 yp_getbykey(keydat
*key
, valdat
*val
)
670 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
673 db_key
.data
= key
->keydat_val
;
674 db_key
.size
= key
->keydat_len
;
676 rval
= yp_get_record(yp_currmap_db
,
677 &db_key
, &db_val
, yp_allow_db
);
679 if (rval
== YP_TRUE
) {
680 val
->valdat_val
= db_val
.data
;
681 val
->valdat_len
= db_val
.size
;
688 yp_firstbykey(keydat
*key
, valdat
*val
)
690 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
693 rval
= yp_first_record(yp_currmap_db
, &db_key
, &db_val
, yp_allow_db
);
695 if (rval
== YP_TRUE
) {
696 key
->keydat_val
= db_key
.data
;
697 key
->keydat_len
= db_key
.size
;
698 val
->valdat_val
= db_val
.data
;
699 val
->valdat_len
= db_val
.size
;
706 yp_nextbykey(keydat
*key
, valdat
*val
)
708 DBT db_key
= { NULL
, 0 }, db_val
= { NULL
, 0 };
711 db_key
.data
= key
->keydat_val
;
712 db_key
.size
= key
->keydat_len
;
714 rval
= yp_next_record(yp_currmap_db
, &db_key
, &db_val
, 0, yp_allow_db
);
716 if (rval
== YP_TRUE
) {
717 key
->keydat_val
= db_key
.data
;
718 key
->keydat_len
= db_key
.size
;
719 val
->valdat_val
= db_val
.data
;
720 val
->valdat_len
= db_val
.size
;