1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1992 Keith Muller.
5 * Copyright (c) 1992, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Keith Muller of the University of California, San Diego.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 5/31/93";
39 #endif
40 #endif /* not lint */
41 #include <sys/cdefs.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <string.h>
45 #include <stdio.h>
46 #include <pwd.h>
47 #include <grp.h>
48 #include <stdlib.h>
49 #include "pax.h"
50 #include "cache.h"
51 #include "extern.h"
52
53 /*
54 * routines that control user, group, uid and gid caches (for the archive
55 * member print routine).
56 * IMPORTANT:
57 * these routines cache BOTH hits and misses, a major performance improvement
58 */
59
60 static int pwopn = 0; /* is password file open */
61 static int gropn = 0; /* is group file open */
62 static UIDC **uidtb = NULL; /* uid to name cache */
63 static GIDC **gidtb = NULL; /* gid to name cache */
64 static UIDC **usrtb = NULL; /* user name to uid cache */
65 static GIDC **grptb = NULL; /* group name to gid cache */
66
67 /*
68 * uidtb_start
69 * creates an empty uidtb
70 * Return:
71 * 0 if ok, -1 otherwise
72 */
73
74 int
uidtb_start(void)75 uidtb_start(void)
76 {
77 static int fail = 0;
78
79 if (uidtb != NULL)
80 return(0);
81 if (fail)
82 return(-1);
83 if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
84 ++fail;
85 paxwarn(1, "Unable to allocate memory for user id cache table");
86 return(-1);
87 }
88 return(0);
89 }
90
91 /*
92 * gidtb_start
93 * creates an empty gidtb
94 * Return:
95 * 0 if ok, -1 otherwise
96 */
97
98 int
gidtb_start(void)99 gidtb_start(void)
100 {
101 static int fail = 0;
102
103 if (gidtb != NULL)
104 return(0);
105 if (fail)
106 return(-1);
107 if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
108 ++fail;
109 paxwarn(1, "Unable to allocate memory for group id cache table");
110 return(-1);
111 }
112 return(0);
113 }
114
115 /*
116 * usrtb_start
117 * creates an empty usrtb
118 * Return:
119 * 0 if ok, -1 otherwise
120 */
121
122 int
usrtb_start(void)123 usrtb_start(void)
124 {
125 static int fail = 0;
126
127 if (usrtb != NULL)
128 return(0);
129 if (fail)
130 return(-1);
131 if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
132 ++fail;
133 paxwarn(1, "Unable to allocate memory for user name cache table");
134 return(-1);
135 }
136 return(0);
137 }
138
139 /*
140 * grptb_start
141 * creates an empty grptb
142 * Return:
143 * 0 if ok, -1 otherwise
144 */
145
146 int
grptb_start(void)147 grptb_start(void)
148 {
149 static int fail = 0;
150
151 if (grptb != NULL)
152 return(0);
153 if (fail)
154 return(-1);
155 if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
156 ++fail;
157 paxwarn(1,"Unable to allocate memory for group name cache table");
158 return(-1);
159 }
160 return(0);
161 }
162
163 /*
164 * name_uid()
165 * caches the name (if any) for the uid. If frc set, we always return the
166 * the stored name (if valid or invalid match). We use a simple hash table.
167 * Return
168 * Pointer to stored name (or an empty string).
169 */
170
171 const char *
name_uid(uid_t uid,int frc)172 name_uid(uid_t uid, int frc)
173 {
174 struct passwd *pw;
175 UIDC *ptr;
176
177 if ((uidtb == NULL) && (uidtb_start() < 0))
178 return("");
179
180 /*
181 * see if we have this uid cached
182 */
183 ptr = uidtb[uid % UID_SZ];
184 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
185 /*
186 * have an entry for this uid
187 */
188 if (frc || (ptr->valid == VALID))
189 return(ptr->name);
190 return("");
191 }
192
193 /*
194 * No entry for this uid, we will add it
195 */
196 if (!pwopn) {
197 setpassent(1);
198 ++pwopn;
199 }
200 if (ptr == NULL)
201 ptr = uidtb[uid % UID_SZ] = (UIDC *)malloc(sizeof(UIDC));
202
203 if ((pw = getpwuid(uid)) == NULL) {
204 /*
205 * no match for this uid in the local password file
206 * a string that is the uid in numeric format
207 */
208 if (ptr == NULL)
209 return("");
210 ptr->uid = uid;
211 ptr->valid = INVALID;
212 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
213 (unsigned long)uid);
214 if (frc == 0)
215 return("");
216 } else {
217 /*
218 * there is an entry for this uid in the password file
219 */
220 if (ptr == NULL)
221 return(pw->pw_name);
222 ptr->uid = uid;
223 (void)strncpy(ptr->name, pw->pw_name, UNMLEN - 1);
224 ptr->name[UNMLEN-1] = '\0';
225 ptr->valid = VALID;
226 }
227 return(ptr->name);
228 }
229
230 /*
231 * name_gid()
232 * caches the name (if any) for the gid. If frc set, we always return the
233 * the stored name (if valid or invalid match). We use a simple hash table.
234 * Return
235 * Pointer to stored name (or an empty string).
236 */
237
238 const char *
name_gid(gid_t gid,int frc)239 name_gid(gid_t gid, int frc)
240 {
241 struct group *gr;
242 GIDC *ptr;
243
244 if ((gidtb == NULL) && (gidtb_start() < 0))
245 return("");
246
247 /*
248 * see if we have this gid cached
249 */
250 ptr = gidtb[gid % GID_SZ];
251 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
252 /*
253 * have an entry for this gid
254 */
255 if (frc || (ptr->valid == VALID))
256 return(ptr->name);
257 return("");
258 }
259
260 /*
261 * No entry for this gid, we will add it
262 */
263 if (!gropn) {
264 setgroupent(1);
265 ++gropn;
266 }
267 if (ptr == NULL)
268 ptr = gidtb[gid % GID_SZ] = (GIDC *)malloc(sizeof(GIDC));
269
270 if ((gr = getgrgid(gid)) == NULL) {
271 /*
272 * no match for this gid in the local group file, put in
273 * a string that is the gid in numeric format
274 */
275 if (ptr == NULL)
276 return("");
277 ptr->gid = gid;
278 ptr->valid = INVALID;
279 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
280 (unsigned long)gid);
281 if (frc == 0)
282 return("");
283 } else {
284 /*
285 * there is an entry for this group in the group file
286 */
287 if (ptr == NULL)
288 return(gr->gr_name);
289 ptr->gid = gid;
290 (void)strncpy(ptr->name, gr->gr_name, GNMLEN - 1);
291 ptr->name[GNMLEN-1] = '\0';
292 ptr->valid = VALID;
293 }
294 return(ptr->name);
295 }
296
297 /*
298 * uid_name()
299 * caches the uid for a given user name. We use a simple hash table.
300 * Return
301 * the uid (if any) for a user name, or a -1 if no match can be found
302 */
303
304 int
uid_name(char * name,uid_t * uid)305 uid_name(char *name, uid_t *uid)
306 {
307 struct passwd *pw;
308 UIDC *ptr;
309 int namelen;
310
311 /*
312 * return -1 for mangled names
313 */
314 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
315 return(-1);
316 if ((usrtb == NULL) && (usrtb_start() < 0))
317 return(-1);
318
319 /*
320 * look up in hash table, if found and valid return the uid,
321 * if found and invalid, return a -1
322 */
323 ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
324 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
325 if (ptr->valid == INVALID)
326 return(-1);
327 *uid = ptr->uid;
328 return(0);
329 }
330
331 if (!pwopn) {
332 setpassent(1);
333 ++pwopn;
334 }
335
336 if (ptr == NULL)
337 ptr = usrtb[st_hash(name, namelen, UNM_SZ)] =
338 (UIDC *)malloc(sizeof(UIDC));
339
340 /*
341 * no match, look it up, if no match store it as an invalid entry,
342 * or store the matching uid
343 */
344 if (ptr == NULL) {
345 if ((pw = getpwnam(name)) == NULL)
346 return(-1);
347 *uid = pw->pw_uid;
348 return(0);
349 }
350 (void)strncpy(ptr->name, name, UNMLEN - 1);
351 ptr->name[UNMLEN-1] = '\0';
352 if ((pw = getpwnam(name)) == NULL) {
353 ptr->valid = INVALID;
354 return(-1);
355 }
356 ptr->valid = VALID;
357 *uid = ptr->uid = pw->pw_uid;
358 return(0);
359 }
360
361 /*
362 * gid_name()
363 * caches the gid for a given group name. We use a simple hash table.
364 * Return
365 * the gid (if any) for a group name, or a -1 if no match can be found
366 */
367
368 int
gid_name(char * name,gid_t * gid)369 gid_name(char *name, gid_t *gid)
370 {
371 struct group *gr;
372 GIDC *ptr;
373 int namelen;
374
375 /*
376 * return -1 for mangled names
377 */
378 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
379 return(-1);
380 if ((grptb == NULL) && (grptb_start() < 0))
381 return(-1);
382
383 /*
384 * look up in hash table, if found and valid return the uid,
385 * if found and invalid, return a -1
386 */
387 ptr = grptb[st_hash(name, namelen, GID_SZ)];
388 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
389 if (ptr->valid == INVALID)
390 return(-1);
391 *gid = ptr->gid;
392 return(0);
393 }
394
395 if (!gropn) {
396 setgroupent(1);
397 ++gropn;
398 }
399 if (ptr == NULL)
400 ptr = grptb[st_hash(name, namelen, GID_SZ)] =
401 (GIDC *)malloc(sizeof(GIDC));
402
403 /*
404 * no match, look it up, if no match store it as an invalid entry,
405 * or store the matching gid
406 */
407 if (ptr == NULL) {
408 if ((gr = getgrnam(name)) == NULL)
409 return(-1);
410 *gid = gr->gr_gid;
411 return(0);
412 }
413
414 (void)strncpy(ptr->name, name, GNMLEN - 1);
415 ptr->name[GNMLEN-1] = '\0';
416 if ((gr = getgrnam(name)) == NULL) {
417 ptr->valid = INVALID;
418 return(-1);
419 }
420 ptr->valid = VALID;
421 *gid = ptr->gid = gr->gr_gid;
422 return(0);
423 }
424