source3/lib/idmap_cache.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    ID Mapping Cache
   4
   5    Copyright (C) Volker Lendecke        2008
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.*/
  19
  20 #include "includes.h"
  21
  22 /**
  23  * Find a sid2uid mapping
  24  * @param[in] sid               the sid to map
  25  * @param[out] puid             where to put the result
  26  * @param[out] expired          is the cache entry expired?
  27  * @retval Was anything in the cache at all?
  28  *
  29  * If *puid == -1 this was a negative mapping.
  30  */
  31
  32 bool idmap_cache_find_sid2uid(const struct dom_sid *sid, uid_t *puid,
  33                               bool *expired)
  34 {
  35         fstring sidstr;
  36         char *key;
  37         char *value;
  38         char *endptr;
  39         time_t timeout;
  40         uid_t uid;
  41         bool ret;
  42
  43         key = talloc_asprintf(talloc_tos(), "IDMAP/SID2UID/%s",
  44                               sid_to_fstring(sidstr, sid));
  45         if (key == NULL) {
  46                 return false;
  47         }
  48         ret = gencache_get(key, &value, &timeout);
  49         TALLOC_FREE(key);
  50         if (!ret) {
  51                 return false;
  52         }
  53         uid = strtol(value, &endptr, 10);
  54         ret = (*endptr == '\0');
  55         SAFE_FREE(value);
  56         if (ret) {
  57                 *puid = uid;
  58                 *expired = (timeout <= time(NULL));
  59         }
  60         return ret;
  61 }
  62
  63 /**
  64  * Find a uid2sid mapping
  65  * @param[in] uid               the uid to map
  66  * @param[out] sid              where to put the result
  67  * @param[out] expired          is the cache entry expired?
  68  * @retval Was anything in the cache at all?
  69  *
  70  * If "is_null_sid(sid)", this was a negative mapping.
  71  */
  72
  73 bool idmap_cache_find_uid2sid(uid_t uid, struct dom_sid *sid, bool *expired)
  74 {
  75         char *key;
  76         char *value;
  77         time_t timeout;
  78         bool ret = true;
  79
  80         key = talloc_asprintf(talloc_tos(), "IDMAP/UID2SID/%d", (int)uid);
  81         if (key == NULL) {
  82                 return false;
  83         }
  84         ret = gencache_get(key, &value, &timeout);
  85         TALLOC_FREE(key);
  86         if (!ret) {
  87                 return false;
  88         }
  89         ZERO_STRUCTP(sid);
  90         if (value[0] != '-') {
  91                 ret = string_to_sid(sid, value);
  92         }
  93         SAFE_FREE(value);
  94         if (ret) {
  95                 *expired = (timeout <= time(NULL));
  96         }
  97         return ret;
  98 }
  99
 100 /**
 101  * Store a mapping in the idmap cache
 102  * @param[in] sid               the sid to map
 103  * @param[in] uid               the uid to map
 104  *
 105  * If both parameters are valid values, then a positive mapping in both
 106  * directions is stored. If "is_null_sid(sid)" is true, then this will be a
 107  * negative mapping of uid, we want to cache that for this uid we could not
 108  * find anything. Likewise if "uid==-1", then we want to cache that we did not
 109  * find a mapping for the sid passed here.
 110  */
 111
 112 void idmap_cache_set_sid2uid(const struct dom_sid *sid, uid_t uid)
 113 {
 114         time_t now = time(NULL);
 115         time_t timeout;
 116         fstring sidstr, key, value;
 117
 118         if (!is_null_sid(sid)) {
 119                 fstr_sprintf(key, "IDMAP/SID2UID/%s",
 120                              sid_to_fstring(sidstr, sid));
 121                 fstr_sprintf(value, "%d", (int)uid);
 122                 timeout = (uid == -1)
 123                         ? lp_idmap_negative_cache_time()
 124                         : lp_idmap_cache_time();
 125                 gencache_set(key, value, now + timeout);
 126         }
 127         if (uid != -1) {
 128                 fstr_sprintf(key, "IDMAP/UID2SID/%d", (int)uid);
 129                 if (is_null_sid(sid)) {
 130                         /* negative uid mapping */
 131                         fstrcpy(value, "-");
 132                         timeout = lp_idmap_negative_cache_time();
 133                 }
 134                 else {
 135                         sid_to_fstring(value, sid);
 136                         timeout = lp_idmap_cache_time();
 137                 }
 138                 gencache_set(key, value, now + timeout);
 139         }
 140 }
 141
 142 /**
 143  * Find a sid2gid mapping
 144  * @param[in] sid               the sid to map
 145  * @param[out] pgid             where to put the result
 146  * @param[out] expired          is the cache entry expired?
 147  * @retval Was anything in the cache at all?
 148  *
 149  * If *pgid == -1 this was a negative mapping.
 150  */
 151
 152 bool idmap_cache_find_sid2gid(const struct dom_sid *sid, gid_t *pgid,
 153                               bool *expired)
 154 {
 155         fstring sidstr;
 156         char *key;
 157         char *value;
 158         char *endptr;
 159         time_t timeout;
 160         gid_t gid;
 161         bool ret;
 162
 163         key = talloc_asprintf(talloc_tos(), "IDMAP/SID2GID/%s",
 164                               sid_to_fstring(sidstr, sid));
 165         if (key == NULL) {
 166                 return false;
 167         }
 168         ret = gencache_get(key, &value, &timeout);
 169         TALLOC_FREE(key);
 170         if (!ret) {
 171                 return false;
 172         }
 173         gid = strtol(value, &endptr, 10);
 174         ret = (*endptr == '\0');
 175         SAFE_FREE(value);
 176         if (ret) {
 177                 *pgid = gid;
 178                 *expired = (timeout <= time(NULL));
 179         }
 180         return ret;
 181 }
 182
 183 /**
 184  * Find a gid2sid mapping
 185  * @param[in] gid               the gid to map
 186  * @param[out] sid              where to put the result
 187  * @param[out] expired          is the cache entry expired?
 188  * @retval Was anything in the cache at all?
 189  *
 190  * If "is_null_sid(sid)", this was a negative mapping.
 191  */
 192
 193 bool idmap_cache_find_gid2sid(gid_t gid, struct dom_sid *sid, bool *expired)
 194 {
 195         char *key;
 196         char *value;
 197         time_t timeout;
 198         bool ret = true;
 199
 200         key = talloc_asprintf(talloc_tos(), "IDMAP/GID2SID/%d", (int)gid);
 201         if (key == NULL) {
 202                 return false;
 203         }
 204         ret = gencache_get(key, &value, &timeout);
 205         TALLOC_FREE(key);
 206         if (!ret) {
 207                 return false;
 208         }
 209         ZERO_STRUCTP(sid);
 210         if (value[0] != '-') {
 211                 ret = string_to_sid(sid, value);
 212         }
 213         SAFE_FREE(value);
 214         if (ret) {
 215                 *expired = (timeout <= time(NULL));
 216         }
 217         return ret;
 218 }
 219
 220 /**
 221  * Store a mapping in the idmap cache
 222  * @param[in] sid               the sid to map
 223  * @param[in] gid               the gid to map
 224  *
 225  * If both parameters are valid values, then a positive mapping in both
 226  * directions is stored. If "is_null_sid(sid)" is true, then this will be a
 227  * negative mapping of gid, we want to cache that for this gid we could not
 228  * find anything. Likewise if "gid==-1", then we want to cache that we did not
 229  * find a mapping for the sid passed here.
 230  */
 231
 232 void idmap_cache_set_sid2gid(const struct dom_sid *sid, gid_t gid)
 233 {
 234         time_t now = time(NULL);
 235         time_t timeout;
 236         fstring sidstr, key, value;
 237
 238         if (!is_null_sid(sid)) {
 239                 fstr_sprintf(key, "IDMAP/SID2GID/%s",
 240                              sid_to_fstring(sidstr, sid));
 241                 fstr_sprintf(value, "%d", (int)gid);
 242                 timeout = (gid == -1)
 243                         ? lp_idmap_negative_cache_time()
 244                         : lp_idmap_cache_time();
 245                 gencache_set(key, value, now + timeout);
 246         }
 247         if (gid != -1) {
 248                 fstr_sprintf(key, "IDMAP/GID2SID/%d", (int)gid);
 249                 if (is_null_sid(sid)) {
 250                         /* negative gid mapping */
 251                         fstrcpy(value, "-");
 252                         timeout = lp_idmap_negative_cache_time();
 253                 }
 254                 else {
 255                         sid_to_fstring(value, sid);
 256                         timeout = lp_idmap_cache_time();
 257                 }
 258                 gencache_set(key, value, now + timeout);
 259         }
 260 }