xref: /freebsd/bin/pax/cache.c (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
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  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)cache.c	8.1 (Berkeley) 5/31/93";
37 #endif
38 #endif /* not lint */
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
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 <unistd.h>
49 #include <stdlib.h>
50 #include "pax.h"
51 #include "cache.h"
52 #include "extern.h"
53 
54 /*
55  * routines that control user, group, uid and gid caches (for the archive
56  * member print routine).
57  * IMPORTANT:
58  * these routines cache BOTH hits and misses, a major performance improvement
59  */
60 
61 static	int pwopn = 0;		/* is password file open */
62 static	int gropn = 0;		/* is group file open */
63 static UIDC **uidtb = NULL;	/* uid to name cache */
64 static GIDC **gidtb = NULL;	/* gid to name cache */
65 static UIDC **usrtb = NULL;	/* user name to uid cache */
66 static GIDC **grptb = NULL;	/* group name to gid cache */
67 
68 /*
69  * uidtb_start
70  *	creates an an empty uidtb
71  * Return:
72  *	0 if ok, -1 otherwise
73  */
74 
75 int
76 uidtb_start(void)
77 {
78 	static int fail = 0;
79 
80 	if (uidtb != NULL)
81 		return(0);
82 	if (fail)
83 		return(-1);
84 	if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
85 		++fail;
86 		paxwarn(1, "Unable to allocate memory for user id cache table");
87 		return(-1);
88 	}
89 	return(0);
90 }
91 
92 /*
93  * gidtb_start
94  *	creates an an empty gidtb
95  * Return:
96  *	0 if ok, -1 otherwise
97  */
98 
99 int
100 gidtb_start(void)
101 {
102 	static int fail = 0;
103 
104 	if (gidtb != NULL)
105 		return(0);
106 	if (fail)
107 		return(-1);
108 	if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
109 		++fail;
110 		paxwarn(1, "Unable to allocate memory for group id cache table");
111 		return(-1);
112 	}
113 	return(0);
114 }
115 
116 /*
117  * usrtb_start
118  *	creates an an empty usrtb
119  * Return:
120  *	0 if ok, -1 otherwise
121  */
122 
123 int
124 usrtb_start(void)
125 {
126 	static int fail = 0;
127 
128 	if (usrtb != NULL)
129 		return(0);
130 	if (fail)
131 		return(-1);
132 	if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
133 		++fail;
134 		paxwarn(1, "Unable to allocate memory for user name cache table");
135 		return(-1);
136 	}
137 	return(0);
138 }
139 
140 /*
141  * grptb_start
142  *	creates an an empty grptb
143  * Return:
144  *	0 if ok, -1 otherwise
145  */
146 
147 int
148 grptb_start(void)
149 {
150 	static int fail = 0;
151 
152 	if (grptb != NULL)
153 		return(0);
154 	if (fail)
155 		return(-1);
156 	if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
157 		++fail;
158 		paxwarn(1,"Unable to allocate memory for group name cache table");
159 		return(-1);
160 	}
161 	return(0);
162 }
163 
164 /*
165  * name_uid()
166  *	caches the name (if any) for the uid. If frc set, we always return the
167  *	the stored name (if valid or invalid match). We use a simple hash table.
168  * Return
169  *	Pointer to stored name (or an empty string).
170  */
171 
172 const char *
173 name_uid(uid_t uid, int frc)
174 {
175 	struct passwd *pw;
176 	UIDC *ptr;
177 
178 	if ((uidtb == NULL) && (uidtb_start() < 0))
179 		return("");
180 
181 	/*
182 	 * see if we have this uid cached
183 	 */
184 	ptr = uidtb[uid % UID_SZ];
185 	if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
186 		/*
187 		 * have an entry for this uid
188 		 */
189 		if (frc || (ptr->valid == VALID))
190 			return(ptr->name);
191 		return("");
192 	}
193 
194 	/*
195 	 * No entry for this uid, we will add it
196 	 */
197 	if (!pwopn) {
198 		setpassent(1);
199 		++pwopn;
200 	}
201 	if (ptr == NULL)
202 		ptr = uidtb[uid % UID_SZ] = (UIDC *)malloc(sizeof(UIDC));
203 
204 	if ((pw = getpwuid(uid)) == NULL) {
205 		/*
206 		 * no match for this uid in the local password file
207 		 * a string that is the uid in numeric format
208 		 */
209 		if (ptr == NULL)
210 			return("");
211 		ptr->uid = uid;
212 		ptr->valid = INVALID;
213 #		ifdef NET2_STAT
214 		(void)snprintf(ptr->name, sizeof(ptr->name), "%u", uid);
215 #		else
216 		(void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
217 			       (unsigned long)uid);
218 #		endif
219 		if (frc == 0)
220 			return("");
221 	} else {
222 		/*
223 		 * there is an entry for this uid in the password file
224 		 */
225 		if (ptr == NULL)
226 			return(pw->pw_name);
227 		ptr->uid = uid;
228 		(void)strncpy(ptr->name, pw->pw_name, UNMLEN - 1);
229 		ptr->name[UNMLEN-1] = '\0';
230 		ptr->valid = VALID;
231 	}
232 	return(ptr->name);
233 }
234 
235 /*
236  * name_gid()
237  *	caches the name (if any) for the gid. If frc set, we always return the
238  *	the stored name (if valid or invalid match). We use a simple hash table.
239  * Return
240  *	Pointer to stored name (or an empty string).
241  */
242 
243 const char *
244 name_gid(gid_t gid, int frc)
245 {
246 	struct group *gr;
247 	GIDC *ptr;
248 
249 	if ((gidtb == NULL) && (gidtb_start() < 0))
250 		return("");
251 
252 	/*
253 	 * see if we have this gid cached
254 	 */
255 	ptr = gidtb[gid % GID_SZ];
256 	if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
257 		/*
258 		 * have an entry for this gid
259 		 */
260 		if (frc || (ptr->valid == VALID))
261 			return(ptr->name);
262 		return("");
263 	}
264 
265 	/*
266 	 * No entry for this gid, we will add it
267 	 */
268 	if (!gropn) {
269 		setgroupent(1);
270 		++gropn;
271 	}
272 	if (ptr == NULL)
273 		ptr = gidtb[gid % GID_SZ] = (GIDC *)malloc(sizeof(GIDC));
274 
275 	if ((gr = getgrgid(gid)) == NULL) {
276 		/*
277 		 * no match for this gid in the local group file, put in
278 		 * a string that is the gid in numeric format
279 		 */
280 		if (ptr == NULL)
281 			return("");
282 		ptr->gid = gid;
283 		ptr->valid = INVALID;
284 #		ifdef NET2_STAT
285 		(void)snprintf(ptr->name, sizeof(ptr->name), "%u", gid);
286 #		else
287 		(void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
288 			       (unsigned long)gid);
289 #		endif
290 		if (frc == 0)
291 			return("");
292 	} else {
293 		/*
294 		 * there is an entry for this group in the group file
295 		 */
296 		if (ptr == NULL)
297 			return(gr->gr_name);
298 		ptr->gid = gid;
299 		(void)strncpy(ptr->name, gr->gr_name, GNMLEN - 1);
300 		ptr->name[GNMLEN-1] = '\0';
301 		ptr->valid = VALID;
302 	}
303 	return(ptr->name);
304 }
305 
306 /*
307  * uid_name()
308  *	caches the uid for a given user name. We use a simple hash table.
309  * Return
310  *	the uid (if any) for a user name, or a -1 if no match can be found
311  */
312 
313 int
314 uid_name(char *name, uid_t *uid)
315 {
316 	struct passwd *pw;
317 	UIDC *ptr;
318 	int namelen;
319 
320 	/*
321 	 * return -1 for mangled names
322 	 */
323 	if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
324 		return(-1);
325 	if ((usrtb == NULL) && (usrtb_start() < 0))
326 		return(-1);
327 
328 	/*
329 	 * look up in hash table, if found and valid return the uid,
330 	 * if found and invalid, return a -1
331 	 */
332 	ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
333 	if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
334 		if (ptr->valid == INVALID)
335 			return(-1);
336 		*uid = ptr->uid;
337 		return(0);
338 	}
339 
340 	if (!pwopn) {
341 		setpassent(1);
342 		++pwopn;
343 	}
344 
345 	if (ptr == NULL)
346 		ptr = usrtb[st_hash(name, namelen, UNM_SZ)] =
347 		  (UIDC *)malloc(sizeof(UIDC));
348 
349 	/*
350 	 * no match, look it up, if no match store it as an invalid entry,
351 	 * or store the matching uid
352 	 */
353 	if (ptr == NULL) {
354 		if ((pw = getpwnam(name)) == NULL)
355 			return(-1);
356 		*uid = pw->pw_uid;
357 		return(0);
358 	}
359 	(void)strncpy(ptr->name, name, UNMLEN - 1);
360 	ptr->name[UNMLEN-1] = '\0';
361 	if ((pw = getpwnam(name)) == NULL) {
362 		ptr->valid = INVALID;
363 		return(-1);
364 	}
365 	ptr->valid = VALID;
366 	*uid = ptr->uid = pw->pw_uid;
367 	return(0);
368 }
369 
370 /*
371  * gid_name()
372  *	caches the gid for a given group name. We use a simple hash table.
373  * Return
374  *	the gid (if any) for a group name, or a -1 if no match can be found
375  */
376 
377 int
378 gid_name(char *name, gid_t *gid)
379 {
380 	struct group *gr;
381 	GIDC *ptr;
382 	int namelen;
383 
384 	/*
385 	 * return -1 for mangled names
386 	 */
387 	if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
388 		return(-1);
389 	if ((grptb == NULL) && (grptb_start() < 0))
390 		return(-1);
391 
392 	/*
393 	 * look up in hash table, if found and valid return the uid,
394 	 * if found and invalid, return a -1
395 	 */
396 	ptr = grptb[st_hash(name, namelen, GID_SZ)];
397 	if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
398 		if (ptr->valid == INVALID)
399 			return(-1);
400 		*gid = ptr->gid;
401 		return(0);
402 	}
403 
404 	if (!gropn) {
405 		setgroupent(1);
406 		++gropn;
407 	}
408 	if (ptr == NULL)
409 		ptr = grptb[st_hash(name, namelen, GID_SZ)] =
410 		  (GIDC *)malloc(sizeof(GIDC));
411 
412 	/*
413 	 * no match, look it up, if no match store it as an invalid entry,
414 	 * or store the matching gid
415 	 */
416 	if (ptr == NULL) {
417 		if ((gr = getgrnam(name)) == NULL)
418 			return(-1);
419 		*gid = gr->gr_gid;
420 		return(0);
421 	}
422 
423 	(void)strncpy(ptr->name, name, GNMLEN - 1);
424 	ptr->name[GNMLEN-1] = '\0';
425 	if ((gr = getgrnam(name)) == NULL) {
426 		ptr->valid = INVALID;
427 		return(-1);
428 	}
429 	ptr->valid = VALID;
430 	*gid = ptr->gid = gr->gr_gid;
431 	return(0);
432 }
433