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 1.17.2.1 2002/02/15 00:47:00 des 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 CIRCLEQ_HEAD(circlehead, circleq_entry) qhead;
82 struct circleq_entry {
84 CIRCLEQ_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 = qhead.cqh_last;
168 CIRCLEQ_REMOVE(&qhead, qptr, links);
174 * Close all databases, erase all database names and empty the queue.
179 struct circleq_entry *qptr;
181 while (qhead.cqh_first != (void *)&qhead) {
182 qptr = qhead.cqh_first; /* save this */
183 CIRCLEQ_REMOVE(&qhead, qhead.cqh_first, 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 for (qptr = qhead.cqh_first; qptr != (void *)&qhead;
229 qptr = qptr->links.cqe_next) {
230 if (!strcmp(qptr->dbptr->name, buf)) {
231 if (qptr->dbptr->flags & flag)
238 if (yp_open_db_cache(domain, map, NULL, 0) == NULL)
241 if (qhead.cqh_first->dbptr->flags & flag)
248 * Add a DB handle and database name to the cache. We only maintain
249 * fixed number of entries in the cache, so if we're asked to store
250 * a new entry when all our slots are already filled, we have to kick
251 * out the entry in the last slot to make room.
254 yp_cache_db(DB *dbp, char *name, int size)
256 struct circleq_entry *qptr;
258 if (numdbs == MAXDBS) {
260 yp_error("queue overflow -- releasing last slot");
265 * Allocate a new queue entry.
268 if ((qptr = yp_malloc_qent()) == NULL) {
269 yp_error("failed to allocate a new cache entry");
273 qptr->dbptr->dbp = dbp;
274 qptr->dbptr->name = strdup(name);
275 qptr->dbptr->size = size;
276 qptr->dbptr->key = NULL;
278 qptr->dbptr->flags = yp_setflags(dbp);
280 CIRCLEQ_INSERT_HEAD(&qhead, qptr, links);
287 * Search the list for a database matching 'name.' If we find it,
288 * move it to the head of the list and return its DB handle. If
289 * not, just fail: yp_open_db_cache() will subsequently try to open
290 * the database itself and call yp_cache_db() to add it to the
293 * The search works like this:
295 * - The caller specifies the name of a database to locate. We try to
296 * find an entry in our queue with a matching name.
298 * - If the caller doesn't specify a key or size, we assume that the
299 * first entry that we encounter with a matching name is returned.
300 * This will result in matches regardless of the key/size values
301 * stored in the queue entry.
303 * - If the caller also specifies a key and length, we check to see
304 * if the key and length saved in the queue entry also matches.
305 * This lets us return a DB handle that's already positioned at the
306 * correct location within a database.
308 * - Once we have a match, it gets migrated to the top of the queue
309 * so that it will be easier to find if another request for
310 * the same database comes in later.
313 yp_find_db(const char *name, const char *key, const int size)
315 struct circleq_entry *qptr;
317 for (qptr = qhead.cqh_first; qptr != (void *)&qhead;
318 qptr = qptr->links.cqe_next) {
319 if (!strcmp(qptr->dbptr->name, name)) {
321 if (size != qptr->dbptr->size ||
322 strncmp(qptr->dbptr->key, key, size))
325 if (qptr->dbptr->size)
328 if (qptr != qhead.cqh_first) {
329 CIRCLEQ_REMOVE(&qhead, qptr, links);
330 CIRCLEQ_INSERT_HEAD(&qhead, qptr, links);
332 return(qptr->dbptr->dbp);
340 * Open a DB database and cache the handle for later use. We first
341 * check the cache to see if the required database is already open.
342 * If so, we fetch the handle from the cache. If not, we try to open
343 * the database and save the handle in the cache for later use.
346 yp_open_db_cache(const char *domain, const char *map, const char *key,
350 char buf[MAXPATHLEN + 2];
352 snprintf(buf, sizeof(buf), "%s/%s", domain, map);
360 if ((dbp = yp_find_db((char *)&buf, key, size)) != NULL) {
363 if ((dbp = yp_open_db(domain, map)) != NULL) {
364 if (yp_cache_db(dbp, (char *)&buf, size)) {
377 * Open a DB database.
380 yp_open_db(const char *domain, const char *map)
383 char buf[MAXPATHLEN + 2];
387 if (map[0] == '.' || strchr(map, '/')) {
388 yp_errno = YP_BADARGS;
393 if (yp_validdomain(domain)) {
398 snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, domain, map);
403 dbp = dbopen(buf,O_RDONLY, PERM_SECURE, DB_HASH, NULL);
410 * We ran out of file descriptors. Nuke an
411 * open one and try again.
413 yp_error("ran out of file descriptors");
434 * Database access routines.
436 * - yp_get_record(): retrieve an arbitrary key/data pair given one key
439 * - yp_first_record(): retrieve first key/data base in a database.
441 * - yp_next_record(): retrieve key/data pair that sequentially follows
442 * the supplied key value in the database.
447 yp_get_record(DB *dbp, const DBT *key, DBT *data, int allow)
450 yp_get_record(const char *domain, const char *map, const DBT *key,
451 DBT *data, int allow)
459 static unsigned char buf[YPMAXRECORD];
463 yp_error("looking up key [%.*s]",
464 key->size, key->data);
467 * Avoid passing back magic "YP_*" entries unless
468 * the caller specifically requested them by setting
471 if (!allow && !strncmp(key->data, "YP_", 3))
475 if ((dbp = yp_open_db(domain, map)) == NULL) {
480 if ((rval = (dbp->get)(dbp, key, data, 0)) != 0) {
482 qhead.cqh_first->dbptr->size = 0;
493 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
494 key->size, key->data, data->size, data->data);
497 if (qhead.cqh_first->dbptr->size) {
498 qhead.cqh_first->dbptr->key = "";
499 qhead.cqh_first->dbptr->size = 0;
502 bcopy((char *)data->data, (char *)&buf, data->size);
503 data->data = (void *)&buf;
511 yp_first_record(const DB *dbp, DBT *key, DBT *data, int allow)
515 static unsigned char buf[YPMAXRECORD];
519 yp_error("retrieving first key in map");
521 if ((rval = (dbp->seq)(dbp,key,data,R_FIRST)) != 0) {
523 qhead.cqh_first->dbptr->size = 0;
531 /* Avoid passing back magic "YP_*" records. */
532 while (!strncmp(key->data, "YP_", 3) && !allow) {
533 if ((rval = (dbp->seq)(dbp,key,data,R_NEXT)) != 0) {
535 qhead.cqh_first->dbptr->size = 0;
545 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
546 key->size, key->data, data->size, data->data);
549 if (qhead.cqh_first->dbptr->size) {
550 qhead.cqh_first->dbptr->key = key->data;
551 qhead.cqh_first->dbptr->size = key->size;
554 bcopy((char *)data->data, (char *)&buf, data->size);
555 data->data = (void *)&buf;
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 qhead.cqh_first->dbptr->key = key->data;
579 qhead.cqh_first->dbptr->size = key->size;
586 yp_error("retrieving next key, previous was: [%.*s]",
587 key->size, key->data);
591 if (qhead.cqh_first->dbptr->key == NULL) {
593 (dbp->seq)(dbp,&lkey,&ldata,R_FIRST);
594 while (key->size != lkey.size ||
595 strncmp((char *)key->data, lkey.data,
597 if ((dbp->seq)(dbp,&lkey,&ldata,R_NEXT)) {
599 qhead.cqh_first->dbptr->size = 0;
609 if ((dbp->seq)(dbp,key,data,R_NEXT)) {
611 qhead.cqh_first->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 qhead.cqh_first->dbptr->size = 0;
626 yp_error("result of lookup: key: [%.*s] data: [%.*s]",
627 key->size, key->data, data->size, data->data);
630 if (qhead.cqh_first->dbptr->size) {
631 qhead.cqh_first->dbptr->key = key->data;
632 qhead.cqh_first->dbptr->size = key->size;
635 bcopy((char *)key->data, (char *)&keybuf, key->size);
636 lkey.data = (void *)&keybuf;
637 lkey.size = key->size;
638 bcopy((char *)data->data, (char *)&datbuf, data->size);
639 data->data = (void *)&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;