2 * Copyright (c) 2003-2007 Tim Kientzle
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.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 #include "archive_platform.h"
27 __FBSDID("$FreeBSD$");
29 #ifdef HAVE_SYS_TYPES_H
30 #include <sys/types.h>
50 #if defined(_WIN32) && !defined(__CYGWIN__)
52 archive_read_disk_set_standard_lookup(struct archive *a)
54 archive_set_error(a, -1, "Standard lookups not available on Windows");
55 return (ARCHIVE_FATAL);
57 #else /* ! (_WIN32 && !__CYGWIN__) */
58 #define name_cache_size 127
60 static const char * const NO_NAME = "(noname)";
63 struct archive *archive;
72 } cache[name_cache_size];
75 static const char * lookup_gname(void *, int64_t);
76 static const char * lookup_uname(void *, int64_t);
77 static void cleanup(void *);
78 static const char * lookup_gname_helper(struct name_cache *, id_t gid);
79 static const char * lookup_uname_helper(struct name_cache *, id_t uid);
82 * Installs functions that use getpwuid()/getgrgid()---along with
83 * a simple cache to accelerate such lookups---into the archive_read_disk
84 * object. This is in a separate file because getpwuid()/getgrgid()
85 * can pull in a LOT of library code (including NIS/LDAP functions, which
86 * pull in DNS resolveers, etc). This can easily top 500kB, which makes
87 * it inappropriate for some space-constrained applications.
89 * Applications that are size-sensitive may want to just use the
90 * real default functions (defined in archive_read_disk.c) that just
91 * use the uid/gid without the lookup. Or define your own custom functions
95 archive_read_disk_set_standard_lookup(struct archive *a)
97 struct name_cache *ucache = malloc(sizeof(struct name_cache));
98 struct name_cache *gcache = malloc(sizeof(struct name_cache));
100 if (ucache == NULL || gcache == NULL) {
101 archive_set_error(a, ENOMEM,
102 "Can't allocate uname/gname lookup cache");
105 return (ARCHIVE_FATAL);
108 memset(ucache, 0, sizeof(*ucache));
110 ucache->size = name_cache_size;
111 memset(gcache, 0, sizeof(*gcache));
113 gcache->size = name_cache_size;
115 archive_read_disk_set_gname_lookup(a, gcache, lookup_gname, cleanup);
116 archive_read_disk_set_uname_lookup(a, ucache, lookup_uname, cleanup);
124 struct name_cache *cache = (struct name_cache *)data;
128 for (i = 0; i < cache->size; i++) {
129 if (cache->cache[i].name != NULL &&
130 cache->cache[i].name != NO_NAME)
131 free((void *)(uintptr_t)cache->cache[i].name);
139 * Lookup uid/gid from uname/gname, return NULL if no match.
142 lookup_name(struct name_cache *cache,
143 const char * (*lookup_fn)(struct name_cache *, id_t), id_t id)
151 slot = id % cache->size;
152 if (cache->cache[slot].name != NULL) {
153 if (cache->cache[slot].id == id) {
155 if (cache->cache[slot].name == NO_NAME)
157 return (cache->cache[slot].name);
159 if (cache->cache[slot].name != NO_NAME)
160 free((void *)(uintptr_t)cache->cache[slot].name);
161 cache->cache[slot].name = NULL;
164 name = (lookup_fn)(cache, id);
166 /* Cache and return the negative response. */
167 cache->cache[slot].name = NO_NAME;
168 cache->cache[slot].id = id;
172 cache->cache[slot].name = name;
173 cache->cache[slot].id = id;
174 return (cache->cache[slot].name);
178 lookup_uname(void *data, int64_t uid)
180 struct name_cache *uname_cache = (struct name_cache *)data;
181 return (lookup_name(uname_cache,
182 &lookup_uname_helper, (id_t)uid));
187 lookup_uname_helper(struct name_cache *cache, id_t id)
189 struct passwd pwent, *result;
194 if (cache->buff_size == 0) {
195 cache->buff_size = 256;
196 cache->buff = malloc(cache->buff_size);
198 if (cache->buff == NULL)
201 result = &pwent; /* Old getpwuid_r ignores last arg. */
202 r = getpwuid_r((uid_t)id, &pwent,
203 cache->buff, cache->buff_size, &result);
208 /* ERANGE means our buffer was too small, but POSIX
209 * doesn't tell us how big the buffer should be, so
210 * we just double it and try again. Because the buffer
211 * is kept around in the cache object, we shouldn't
212 * have to do this very often. */
213 nbuff_size = cache->buff_size * 2;
214 nbuff = realloc(cache->buff, nbuff_size);
218 cache->buff_size = nbuff_size;
221 archive_set_error(cache->archive, errno,
222 "Can't lookup user for id %d", (int)id);
228 return strdup(result->pw_name);
232 lookup_uname_helper(struct name_cache *cache, id_t id)
234 struct passwd *result;
236 result = getpwuid((uid_t)id);
241 return strdup(result->pw_name);
246 lookup_gname(void *data, int64_t gid)
248 struct name_cache *gname_cache = (struct name_cache *)data;
249 return (lookup_name(gname_cache,
250 &lookup_gname_helper, (id_t)gid));
255 lookup_gname_helper(struct name_cache *cache, id_t id)
257 struct group grent, *result;
262 if (cache->buff_size == 0) {
263 cache->buff_size = 256;
264 cache->buff = malloc(cache->buff_size);
266 if (cache->buff == NULL)
269 result = &grent; /* Old getgrgid_r ignores last arg. */
270 r = getgrgid_r((gid_t)id, &grent,
271 cache->buff, cache->buff_size, &result);
276 /* ERANGE means our buffer was too small, but POSIX
277 * doesn't tell us how big the buffer should be, so
278 * we just double it and try again. */
279 nbuff_size = cache->buff_size * 2;
280 nbuff = realloc(cache->buff, nbuff_size);
284 cache->buff_size = nbuff_size;
287 archive_set_error(cache->archive, errno,
288 "Can't lookup group for id %d", (int)id);
294 return strdup(result->gr_name);
298 lookup_gname_helper(struct name_cache *cache, id_t id)
300 struct group *result;
302 result = getgrgid((gid_t)id);
307 return strdup(result->gr_name);
311 #endif /* ! (_WIN32 && !__CYGWIN__) */