1 /*-
2 * Copyright (c) 1992 Keith Muller.
3 * Copyright (c) 1992, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Keith Muller of the University of California, San Diego.
8 *
9 * %sccs.include.redist.c%
10 */
11
12 #ifndef lint
13 static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 05/31/93";
14 #endif /* not lint */
15
16 #include <sys/types.h>
17 #include <sys/time.h>
18 #include <sys/stat.h>
19 #include <sys/param.h>
20 #include <string.h>
21 #include <stdio.h>
22 #include <ctype.h>
23 #include <pwd.h>
24 #include <grp.h>
25 #include <unistd.h>
26 #include <stdlib.h>
27 #include "pax.h"
28 #include "cache.h"
29 #include "extern.h"
30
31 /*
32 * routines that control user, group, uid and gid caches (for the archive
33 * member print routine).
34 * IMPORTANT:
35 * these routines cache BOTH hits and misses, a major performance improvement
36 */
37
38 static int pwopn = 0; /* is password file open */
39 static int gropn = 0; /* is group file open */
40 static UIDC **uidtb = NULL; /* uid to name cache */
41 static GIDC **gidtb = NULL; /* gid to name cache */
42 static UIDC **usrtb = NULL; /* user name to uid cache */
43 static GIDC **grptb = NULL; /* group name to gid cache */
44
45 /*
46 * uidtb_start
47 * creates an an empty uidtb
48 * Return:
49 * 0 if ok, -1 otherwise
50 */
51
52 #if __STDC__
53 int
uidtb_start(void)54 uidtb_start(void)
55 #else
56 int
57 uidtb_start()
58 #endif
59 {
60 static int fail = 0;
61
62 if (uidtb != NULL)
63 return(0);
64 if (fail)
65 return(-1);
66 if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
67 ++fail;
68 warn(1, "Unable to allocate memory for user id cache table");
69 return(-1);
70 }
71 return(0);
72 }
73
74 /*
75 * gidtb_start
76 * creates an an empty gidtb
77 * Return:
78 * 0 if ok, -1 otherwise
79 */
80
81 #if __STDC__
82 int
gidtb_start(void)83 gidtb_start(void)
84 #else
85 int
86 gidtb_start()
87 #endif
88 {
89 static int fail = 0;
90
91 if (gidtb != NULL)
92 return(0);
93 if (fail)
94 return(-1);
95 if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
96 ++fail;
97 warn(1, "Unable to allocate memory for group id cache table");
98 return(-1);
99 }
100 return(0);
101 }
102
103 /*
104 * usrtb_start
105 * creates an an empty usrtb
106 * Return:
107 * 0 if ok, -1 otherwise
108 */
109
110 #if __STDC__
111 int
usrtb_start(void)112 usrtb_start(void)
113 #else
114 int
115 usrtb_start()
116 #endif
117 {
118 static int fail = 0;
119
120 if (usrtb != NULL)
121 return(0);
122 if (fail)
123 return(-1);
124 if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
125 ++fail;
126 warn(1, "Unable to allocate memory for user name cache table");
127 return(-1);
128 }
129 return(0);
130 }
131
132 /*
133 * grptb_start
134 * creates an an empty grptb
135 * Return:
136 * 0 if ok, -1 otherwise
137 */
138
139 #if __STDC__
140 int
grptb_start(void)141 grptb_start(void)
142 #else
143 int
144 grptb_start()
145 #endif
146 {
147 static int fail = 0;
148
149 if (grptb != NULL)
150 return(0);
151 if (fail)
152 return(-1);
153 if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
154 ++fail;
155 warn(1,"Unable to allocate memory for group name cache table");
156 return(-1);
157 }
158 return(0);
159 }
160
161 /*
162 * name_uid()
163 * caches the name (if any) for the uid. If frc set, we always return the
164 * the stored name (if valid or invalid match). We use a simple hash table.
165 * Return
166 * Pointer to stored name (or a empty string)
167 */
168
169 #if __STDC__
170 char *
name_uid(uid_t uid,int frc)171 name_uid(uid_t uid, int frc)
172 #else
173 char *
174 name_uid(uid, frc)
175 uid_t uid;
176 int frc;
177 #endif
178 {
179 register struct passwd *pw;
180 register UIDC *ptr;
181
182 if ((uidtb == NULL) && (uidtb_start() < 0))
183 return("");
184
185 /*
186 * see if we have this uid cached
187 */
188 ptr = uidtb[uid % UID_SZ];
189 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
190 /*
191 * have an entry for this uid
192 */
193 if (frc || (ptr->valid == VALID))
194 return(ptr->name);
195 return("");
196 }
197
198 /*
199 * No entry for this uid, we will add it
200 */
201 if (!pwopn) {
202 setpassent(1);
203 ++pwopn;
204 }
205 if (ptr == NULL)
206 ptr = (UIDC *)malloc(sizeof(UIDC));
207
208 if ((pw = getpwuid(uid)) == NULL) {
209 /*
210 * no match for this uid in the local password file
211 * a string that is the uid in numberic format
212 */
213 if (ptr == NULL)
214 return("");
215 ptr->uid = uid;
216 ptr->valid = INVALID;
217 # ifdef NET2_STAT
218 (void)sprintf(ptr->name, "%u", uid);
219 # else
220 (void)sprintf(ptr->name, "%lu", uid);
221 # endif
222 if (frc == 0)
223 return("");
224 } else {
225 /*
226 * there is an entry for this uid in the password file
227 */
228 if (ptr == NULL)
229 return(pw->pw_name);
230 ptr->uid = uid;
231 (void)strncpy(ptr->name, pw->pw_name, UNMLEN);
232 ptr->name[UNMLEN-1] = '\0';
233 ptr->valid = VALID;
234 }
235 return(ptr->name);
236 }
237
238 /*
239 * name_gid()
240 * caches the name (if any) for the gid. If frc set, we always return the
241 * the stored name (if valid or invalid match). We use a simple hash table.
242 * Return
243 * Pointer to stored name (or a empty string)
244 */
245
246 #if __STDC__
247 char *
name_gid(gid_t gid,int frc)248 name_gid(gid_t gid, int frc)
249 #else
250 char *
251 name_gid(gid, frc)
252 gid_t gid;
253 int frc;
254 #endif
255 {
256 register struct group *gr;
257 register GIDC *ptr;
258
259 if ((gidtb == NULL) && (gidtb_start() < 0))
260 return("");
261
262 /*
263 * see if we have this gid cached
264 */
265 ptr = gidtb[gid % GID_SZ];
266 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
267 /*
268 * have an entry for this gid
269 */
270 if (frc || (ptr->valid == VALID))
271 return(ptr->name);
272 return("");
273 }
274
275 /*
276 * No entry for this gid, we will add it
277 */
278 if (!gropn) {
279 setgroupent(1);
280 ++gropn;
281 }
282 if (ptr == NULL)
283 ptr = (GIDC *)malloc(sizeof(GIDC));
284
285 if ((gr = getgrgid(gid)) == NULL) {
286 /*
287 * no match for this gid in the local group file, put in
288 * a string that is the gid in numberic format
289 */
290 if (ptr == NULL)
291 return("");
292 ptr->gid = gid;
293 ptr->valid = INVALID;
294 # ifdef NET2_STAT
295 (void)sprintf(ptr->name, "%u", gid);
296 # else
297 (void)sprintf(ptr->name, "%lu", gid);
298 # endif
299 if (frc == 0)
300 return("");
301 } else {
302 /*
303 * there is an entry for this group in the group file
304 */
305 if (ptr == NULL)
306 return(gr->gr_name);
307 ptr->gid = gid;
308 (void)strncpy(ptr->name, gr->gr_name, GNMLEN);
309 ptr->name[GNMLEN-1] = '\0';
310 ptr->valid = VALID;
311 }
312 return(ptr->name);
313 }
314
315 /*
316 * uid_name()
317 * caches the uid for a given user name. We use a simple hash table.
318 * Return
319 * the uid (if any) for a user name, or a -1 if no match can be found
320 */
321
322 #if __STDC__
323 int
uid_name(char * name,uid_t * uid)324 uid_name(char *name, uid_t *uid)
325 #else
326 int
327 uid_name(name, uid)
328 char *name;
329 uid_t *uid;
330 #endif
331 {
332 register struct passwd *pw;
333 register UIDC *ptr;
334 register int namelen;
335
336 /*
337 * return -1 for mangled names
338 */
339 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
340 return(-1);
341 if ((usrtb == NULL) && (usrtb_start() < 0))
342 return(-1);
343
344 /*
345 * look up in hash table, if found and valid return the uid,
346 * if found and invalid, return a -1
347 */
348 ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
349 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
350 if (ptr->valid == INVALID)
351 return(-1);
352 *uid = ptr->uid;
353 return(0);
354 }
355
356 if (!pwopn) {
357 setpassent(1);
358 ++pwopn;
359 }
360
361 if (ptr == NULL)
362 ptr = (UIDC *)malloc(sizeof(UIDC));
363
364 /*
365 * no match, look it up, if no match store it as an invalid entry,
366 * or store the matching uid
367 */
368 if (ptr == NULL) {
369 if ((pw = getpwnam(name)) == NULL)
370 return(-1);
371 *uid = pw->pw_uid;
372 return(0);
373 }
374 (void)strncpy(ptr->name, name, UNMLEN);
375 ptr->name[UNMLEN-1] = '\0';
376 if ((pw = getpwnam(name)) == NULL) {
377 ptr->valid = INVALID;
378 return(-1);
379 }
380 ptr->valid = VALID;
381 *uid = ptr->uid = pw->pw_uid;
382 return(0);
383 }
384
385 /*
386 * gid_name()
387 * caches the gid for a given group name. We use a simple hash table.
388 * Return
389 * the gid (if any) for a group name, or a -1 if no match can be found
390 */
391
392 #if __STDC__
393 int
gid_name(char * name,gid_t * gid)394 gid_name(char *name, gid_t *gid)
395 #else
396 int
397 gid_name(name, gid)
398 char *name;
399 gid_t *gid;
400 #endif
401 {
402 register struct group *gr;
403 register GIDC *ptr;
404 register int namelen;
405
406 /*
407 * return -1 for mangled names
408 */
409 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
410 return(-1);
411 if ((grptb == NULL) && (grptb_start() < 0))
412 return(-1);
413
414 /*
415 * look up in hash table, if found and valid return the uid,
416 * if found and invalid, return a -1
417 */
418 ptr = grptb[st_hash(name, namelen, GID_SZ)];
419 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
420 if (ptr->valid == INVALID)
421 return(-1);
422 *gid = ptr->gid;
423 return(0);
424 }
425
426 if (!gropn) {
427 setgroupent(1);
428 ++gropn;
429 }
430 if (ptr == NULL)
431 ptr = (GIDC *)malloc(sizeof(GIDC));
432
433 /*
434 * no match, look it up, if no match store it as an invalid entry,
435 * or store the matching gid
436 */
437 if (ptr == NULL) {
438 if ((gr = getgrnam(name)) == NULL)
439 return(-1);
440 *gid = gr->gr_gid;
441 return(0);
442 }
443
444 (void)strncpy(ptr->name, name, GNMLEN);
445 ptr->name[GNMLEN-1] = '\0';
446 if ((gr = getgrnam(name)) == NULL) {
447 ptr->valid = INVALID;
448 return(-1);
449 }
450 ptr->valid = VALID;
451 *gid = ptr->gid = gr->gr_gid;
452 return(0);
453 }
454