1 /* $NetBSD: ypdb.c,v 1.13 2023/08/01 08:47:25 mrg Exp $ */
2
3 /*
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Margo Seltzer.
10 *
11 * This code is derived from ndbm module of BSD4.4 db (hash) by
12 * Mats O Jansson
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 * 3. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
27 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
28 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
30 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39 #include <sys/cdefs.h>
40 #ifndef lint
41 __RCSID("$NetBSD: ypdb.c,v 1.13 2023/08/01 08:47:25 mrg Exp $");
42 #endif
43
44 #include <sys/param.h>
45 #include <sys/types.h>
46 #include <sys/stat.h>
47
48 #include <db.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56
57 #include <rpcsvc/yp.h>
58
59 #include "ypdb.h"
60
61 static DBM *_ypdb_dbopen(const char *, int, mode_t);
62
63 /*
64 * ypdb_open --
65 * dbopen(3) file, read-only.
66 * First ensure that file has a suffix of YPDB_SUFFIX.
67 * Try opening as a DB_BTREE first, then DB_HASH.
68 *
69 * Returns:
70 * *DBM on success
71 * NULL on failure
72 */
73
74 DBM *
ypdb_open(const char * file)75 ypdb_open(const char *file)
76 {
77 char path[MAXPATHLEN];
78 const char *cp, *suffix;
79
80 cp = strrchr(file, '.');
81 if (cp != NULL && strcmp(cp, YPDB_SUFFIX) == 0)
82 suffix = "";
83 else
84 suffix = YPDB_SUFFIX;
85 if ((size_t)snprintf(path, sizeof(path), "%s%s", file, suffix) >
86 sizeof(path)) {
87 warnx("File name `%s' is too long", file);
88 return NULL;
89 }
90 return _ypdb_dbopen(path, O_RDONLY, 0444);
91 }
92
93 /*
94 * ypdb_mktemp --
95 * Create a temporary file using mkstemp(3) based on the
96 * template provided in file.
97 * dbopen(3) file, read-write, 0644 (modified by umask(2)).
98 * Try opening as a DB_BTREE first, then DB_HASH.
99 * file won't have YPDB_SUFFIX.
100 *
101 * Returns:
102 * *DBM on success; file now exists.
103 * NULL on failure
104 */
105
106 DBM *
ypdb_mktemp(char * file)107 ypdb_mktemp(char *file)
108 {
109 int fd = -1;
110 DBM *db = NULL;
111 mode_t myumask;
112 int save_errno;
113
114 if ((fd = mkstemp(file)) == -1)
115 return NULL;
116
117 myumask = umask(0);
118 (void)umask(myumask);
119 if (fchmod(fd, 0644 & ~myumask) == -1)
120 goto bad;
121
122 (void) close(fd);
123 fd = -1;
124
125 if ((db = _ypdb_dbopen(file, O_RDWR, 0644)) == NULL)
126 goto bad;
127
128 return db;
129
130 bad:
131 save_errno = errno;
132 if (fd != 1)
133 (void) close(fd);
134 (void) unlink(file);
135 errno = save_errno;
136 return NULL;
137 }
138
139 /*
140 * _ypdb_dbopen --
141 * dbopen(3) path with the flags & mode.
142 * Try opening as a DB_BTREE first, then DB_HASH.
143 */
144
145 static DBM *
_ypdb_dbopen(const char * path,int flags,mode_t mode)146 _ypdb_dbopen(const char *path, int flags, mode_t mode)
147 {
148 DBM *db;
149 BTREEINFO info;
150
151 /* try our btree format first */
152 info.flags = 0;
153 info.cachesize = 0;
154 info.maxkeypage = 0;
155 info.minkeypage = 0;
156 info.psize = 0;
157 info.compare = NULL;
158 info.prefix = NULL;
159 info.lorder = 0;
160 db = (DBM *)dbopen(path, flags, mode, DB_BTREE, (void *)&info);
161 if (db != NULL || errno != EFTYPE)
162 return (db);
163
164 /* fallback to standard hash (for sendmail's aliases.db) */
165 db = (DBM *)dbopen(path, flags, mode, DB_HASH, NULL);
166 return (db);
167 }
168
169 /*
170 * ypdb_close --
171 * Close the db
172 */
173
174 void
ypdb_close(DBM * db)175 ypdb_close(DBM *db)
176 {
177 (void)(db->close)(db);
178 }
179
180 /*
181 * Returns:
182 * DATUM on success
183 * NULL on failure
184 */
185
186 datum
ypdb_fetch(DBM * db,datum key)187 ypdb_fetch(DBM *db, datum key)
188 {
189 datum retkey;
190 DBT nk, nd;
191 int status;
192
193 nk.data = key.dptr;
194 nk.size = key.dsize;
195 status = (db->get)(db, &nk, &nd, 0);
196 if (status) {
197 retkey.dptr = NULL;
198 retkey.dsize = 0;
199 } else {
200 retkey.dptr = nd.data;
201 retkey.dsize = nd.size;
202 }
203 return (retkey);
204 }
205
206 /*
207 * Returns:
208 * DATUM on success
209 * NULL on failure
210 */
211
212 datum
ypdb_firstkey(DBM * db)213 ypdb_firstkey(DBM *db)
214 {
215 int status;
216 datum retkey;
217 DBT nk, nd;
218
219 status = (db->seq)(db, &nk, &nd, R_FIRST);
220 if (status) {
221 retkey.dptr = NULL;
222 retkey.dsize = 0;
223 } else {
224 retkey.dptr = nk.data;
225 retkey.dsize = nk.size;
226 }
227 return (retkey);
228 }
229
230 /*
231 * Returns:
232 * DATUM on success
233 * NULL on failure
234 */
235
236 datum
ypdb_nextkey(DBM * db)237 ypdb_nextkey(DBM *db)
238 {
239 int status;
240 datum retkey;
241 DBT nk, nd;
242
243 status = (db->seq)(db, &nk, &nd, R_NEXT);
244 if (status) {
245 retkey.dptr = NULL;
246 retkey.dsize = 0;
247 } else {
248 retkey.dptr = nk.data;
249 retkey.dsize = nk.size;
250 }
251 return (retkey);
252 }
253
254 /*
255 * Returns:
256 * DATUM on success
257 * NULL on failure
258 */
259
260 datum
ypdb_setkey(DBM * db,datum key)261 ypdb_setkey(DBM *db, datum key)
262 {
263 int status;
264 DBT nk, nd;
265
266 nk.data = key.dptr;
267 nk.size = key.dsize;
268 status = (db->seq)(db, &nk, &nd, R_CURSOR);
269 if (status) {
270 key.dptr = NULL;
271 key.dsize = 0;
272 }
273 return (key);
274 }
275
276 /*
277 * Returns:
278 * 0 on success
279 * <0 failure
280 */
281
282 int
ypdb_delete(DBM * db,datum key)283 ypdb_delete(DBM *db, datum key)
284 {
285 int status;
286 DBT nk;
287
288 nk.data = key.dptr;
289 nk.size = key.dsize;
290 status = (db->del)(db, &nk, 0);
291 if (status)
292 return (-1);
293 else
294 return (0);
295 }
296
297 /*
298 * Returns:
299 * 0 on success
300 * <0 failure
301 * 1 if YPDB_INSERT and entry exists
302 */
303
304 int
ypdb_store(DBM * db,datum key,datum content,int flags)305 ypdb_store(DBM *db, datum key, datum content, int flags)
306 {
307 DBT nk, nd;
308
309 if (key.dsize > YPMAXRECORD || content.dsize > YPMAXRECORD)
310 return -1;
311 nk.data = key.dptr;
312 nk.size = key.dsize;
313 nd.data = content.dptr;
314 nd.size = content.dsize;
315 return ((db->put)(db, &nk, &nd,
316 (flags == YPDB_INSERT) ? R_NOOVERWRITE : 0));
317 }
318