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;