source4/dsdb/samdb/ldb_modules/anr.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2007
   5    Copyright (C) Simo Sorce <idra@samba.org> 2008
   6    Copyright (C) Andrew Tridgell  2004
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 /*
  23  *  Name: ldb
  24  *
  25  *  Component: ldb anr module
  26  *
  27  *  Description: module to implement 'ambiguous name resolution'
  28  *
  29  *  Author: Andrew Bartlett
  30  */
  31
  32 #include "includes.h"
  33 #include "ldb_module.h"
  34 #include "dsdb/samdb/samdb.h"
  35
  36 /**
  37  * Make a and 'and' or 'or' tree from the two supplied elements
  38  */
  39 static struct ldb_parse_tree *make_parse_list(struct ldb_module *module,
  40                                        TALLOC_CTX *mem_ctx, enum ldb_parse_op op,
  41                                        struct ldb_parse_tree *first_arm, struct ldb_parse_tree *second_arm)
  42 {
  43         struct ldb_context *ldb;
  44         struct ldb_parse_tree *list;
  45
  46         ldb = ldb_module_get_ctx(module);
  47
  48         list = talloc(mem_ctx, struct ldb_parse_tree);
  49         if (list == NULL){
  50                 ldb_oom(ldb);
  51                 return NULL;
  52         }
  53         list->operation = op;
  54
  55         list->u.list.num_elements = 2;
  56         list->u.list.elements = talloc_array(list, struct ldb_parse_tree *, 2);
  57         if (!list->u.list.elements) {
  58                 ldb_oom(ldb);
  59                 return NULL;
  60         }
  61         list->u.list.elements[0] = talloc_steal(list, first_arm);
  62         list->u.list.elements[1] = talloc_steal(list, second_arm);
  63         return list;
  64 }
  65
  66 /**
  67  * Make an equality or prefix match tree, from the attribute, operation and matching value supplied
  68  */
  69 static struct ldb_parse_tree *make_match_tree(struct ldb_module *module,
  70                                               TALLOC_CTX *mem_ctx,
  71                                               enum ldb_parse_op op,
  72                                               const char *attr,
  73                                               struct ldb_val *match)
  74 {
  75         struct ldb_context *ldb;
  76         struct ldb_parse_tree *match_tree;
  77
  78         ldb = ldb_module_get_ctx(module);
  79
  80         match_tree = talloc(mem_ctx, struct ldb_parse_tree);
  81
  82         /* Depending on what type of match was selected, fill in the right part of the union */
  83
  84         match_tree->operation = op;
  85         switch (op) {
  86         case LDB_OP_SUBSTRING:
  87                 match_tree->u.substring.attr = attr;
  88
  89                 match_tree->u.substring.start_with_wildcard = 0;
  90                 match_tree->u.substring.end_with_wildcard = 1;
  91                 match_tree->u.substring.chunks = talloc_array(match_tree, struct ldb_val *, 2);
  92
  93                 if (match_tree->u.substring.chunks == NULL){
  94                         talloc_free(match_tree);
  95                         ldb_oom(ldb);
  96                         return NULL;
  97                 }
  98                 match_tree->u.substring.chunks[0] = match;
  99                 match_tree->u.substring.chunks[1] = NULL;
 100                 break;
 101         case LDB_OP_EQUALITY:
 102                 match_tree->u.equality.attr = attr;
 103                 match_tree->u.equality.value = *match;
 104                 break;
 105         default:
 106                 talloc_free(match_tree);
 107                 return NULL;
 108         }
 109         return match_tree;
 110 }
 111
 112 struct anr_context {
 113         bool found_anr;
 114         struct ldb_module *module;
 115         struct ldb_request *req;
 116 };
 117
 118 /**
 119  * Given the match for an 'ambigious name resolution' query, create a
 120  * parse tree with an 'or' of all the anr attributes in the schema.
 121  */
 122
 123 /**
 124  * Callback function to do the heavy lifting for the parse tree walker
 125  */
 126 static int anr_replace_value(struct anr_context *ac,
 127                              TALLOC_CTX *mem_ctx,
 128                              struct ldb_val *match,
 129                              struct ldb_parse_tree **ntree)
 130 {
 131         struct ldb_parse_tree *tree = NULL;
 132         struct ldb_module *module = ac->module;
 133         struct ldb_parse_tree *match_tree;
 134         struct dsdb_attribute *cur;
 135         const struct dsdb_schema *schema;
 136         struct ldb_context *ldb;
 137         uint8_t *p;
 138         enum ldb_parse_op op;
 139
 140         ldb = ldb_module_get_ctx(module);
 141
 142         schema = dsdb_get_schema(ldb, ac);
 143         if (!schema) {
 144                 ldb_asprintf_errstring(ldb, "no schema with which to construct anr filter");
 145                 return LDB_ERR_OPERATIONS_ERROR;
 146         }
 147
 148         ac->found_anr = true;
 149
 150         if (match->length > 1 && match->data[0] == '=') {
 151                 struct ldb_val *match2 = talloc(mem_ctx, struct ldb_val);
 152                 *match2 = data_blob_const(match->data+1, match->length - 1);
 153                 if (match2 == NULL){
 154                         ldb_oom(ldb);
 155                         return LDB_ERR_OPERATIONS_ERROR;
 156                 }
 157                 match = match2;
 158                 op = LDB_OP_EQUALITY;
 159         } else {
 160                 op = LDB_OP_SUBSTRING;
 161         }
 162         for (cur = schema->attributes; cur; cur = cur->next) {
 163                 if (!(cur->searchFlags & SEARCH_FLAG_ANR)) continue;
 164                 match_tree = make_match_tree(module, mem_ctx, op, cur->lDAPDisplayName, match);
 165
 166                 if (tree) {
 167                         /* Inject an 'or' with the current tree */
 168                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, match_tree);
 169                         if (tree == NULL) {
 170                                 ldb_oom(ldb);
 171                                 return LDB_ERR_OPERATIONS_ERROR;
 172                         }
 173                 } else {
 174                         tree = match_tree;
 175                 }
 176         }
 177
 178
 179         /* If the search term has a space in it,
 180            split it up at the first space.  */
 181
 182         p = memchr(match->data, ' ', match->length);
 183
 184         if (p) {
 185                 struct ldb_parse_tree *first_split_filter, *second_split_filter, *split_filters, *match_tree_1, *match_tree_2;
 186                 struct ldb_val *first_match = talloc(tree, struct ldb_val);
 187                 struct ldb_val *second_match = talloc(tree, struct ldb_val);
 188                 if (!first_match || !second_match) {
 189                         ldb_oom(ldb);
 190                         return LDB_ERR_OPERATIONS_ERROR;
 191                 }
 192                 *first_match = data_blob_const(match->data, p-match->data);
 193                 *second_match = data_blob_const(p+1, match->length - (p-match->data) - 1);
 194
 195                 /* Add (|(&(givenname=first)(sn=second))(&(givenname=second)(sn=first))) */
 196
 197                 match_tree_1 = make_match_tree(module, mem_ctx, op, "givenName", first_match);
 198                 match_tree_2 = make_match_tree(module, mem_ctx, op, "sn", second_match);
 199
 200                 first_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 201                 if (first_split_filter == NULL){
 202                         ldb_oom(ldb);
 203                         return LDB_ERR_OPERATIONS_ERROR;
 204                 }
 205
 206                 match_tree_1 = make_match_tree(module, mem_ctx, op, "sn", first_match);
 207                 match_tree_2 = make_match_tree(module, mem_ctx, op, "givenName", second_match);
 208
 209                 second_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 210                 if (second_split_filter == NULL){
 211                         ldb_oom(ldb);
 212                         return LDB_ERR_OPERATIONS_ERROR;
 213                 }
 214
 215                 split_filters = make_parse_list(module, mem_ctx,  LDB_OP_OR,
 216                                                 first_split_filter, second_split_filter);
 217                 if (split_filters == NULL) {
 218                         ldb_oom(ldb);
 219                         return LDB_ERR_OPERATIONS_ERROR;
 220                 }
 221
 222                 if (tree) {
 223                         /* Inject an 'or' with the current tree */
 224                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, split_filters);
 225                 } else {
 226                         tree = split_filters;
 227                 }
 228         }
 229         *ntree = tree;
 230         return LDB_SUCCESS;
 231 }
 232
 233 /*
 234   replace any occurances of an attribute with a new, generated attribute tree
 235 */
 236 static int anr_replace_subtrees(struct anr_context *ac,
 237                                 struct ldb_parse_tree *tree,
 238                                 const char *attr,
 239                                 struct ldb_parse_tree **ntree)
 240 {
 241         int ret;
 242         unsigned int i;
 243
 244         switch (tree->operation) {
 245         case LDB_OP_AND:
 246         case LDB_OP_OR:
 247                 for (i=0;i<tree->u.list.num_elements;i++) {
 248                         ret = anr_replace_subtrees(ac, tree->u.list.elements[i],
 249                                                    attr, &tree->u.list.elements[i]);
 250                         if (ret != LDB_SUCCESS) {
 251                                 return ret;
 252                         }
 253                         *ntree = tree;
 254                 }
 255                 break;
 256         case LDB_OP_NOT:
 257                 ret = anr_replace_subtrees(ac, tree->u.isnot.child, attr, &tree->u.isnot.child);
 258                 if (ret != LDB_SUCCESS) {
 259                         return ret;
 260                 }
 261                 *ntree = tree;
 262                 break;
 263         case LDB_OP_EQUALITY:
 264                 if (ldb_attr_cmp(tree->u.equality.attr, attr) == 0) {
 265                         ret = anr_replace_value(ac, tree, &tree->u.equality.value, ntree);
 266                         if (ret != LDB_SUCCESS) {
 267                                 return ret;
 268                         }
 269                 }
 270                 break;
 271         case LDB_OP_SUBSTRING:
 272                 if (ldb_attr_cmp(tree->u.substring.attr, attr) == 0) {
 273                         if (tree->u.substring.start_with_wildcard == 0 &&
 274                             tree->u.substring.end_with_wildcard == 1 &&
 275                             tree->u.substring.chunks[0] != NULL &&
 276                             tree->u.substring.chunks[1] == NULL) {
 277                                 ret = anr_replace_value(ac, tree, tree->u.substring.chunks[0], ntree);
 278                                 if (ret != LDB_SUCCESS) {
 279                                         return ret;
 280                                 }
 281                         }
 282                 }
 283                 break;
 284         default:
 285                 break;
 286         }
 287
 288         return LDB_SUCCESS;
 289 }
 290
 291 static int anr_search_callback(struct ldb_request *req, struct ldb_reply *ares)
 292 {
 293         struct anr_context *ac;
 294
 295         ac = talloc_get_type(req->context, struct anr_context);
 296
 297         if (!ares) {
 298                 return ldb_module_done(ac->req, NULL, NULL,
 299                                         LDB_ERR_OPERATIONS_ERROR);
 300         }
 301         if (ares->error != LDB_SUCCESS) {
 302                 return ldb_module_done(ac->req, ares->controls,
 303                                         ares->response, ares->error);
 304         }
 305
 306         switch (ares->type) {
 307         case LDB_REPLY_ENTRY:
 308                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
 309
 310         case LDB_REPLY_REFERRAL:
 311                 return ldb_module_send_referral(ac->req, ares->referral);
 312
 313         case LDB_REPLY_DONE:
 314                 return ldb_module_done(ac->req, ares->controls,
 315                                         ares->response, LDB_SUCCESS);
 316
 317         }
 318         return LDB_SUCCESS;
 319 }
 320
 321 /* search */
 322 static int anr_search(struct ldb_module *module, struct ldb_request *req)
 323 {
 324         struct ldb_context *ldb;
 325         struct ldb_parse_tree *anr_tree;
 326         struct ldb_request *down_req;
 327         struct anr_context *ac;
 328         int ret;
 329
 330         ldb = ldb_module_get_ctx(module);
 331
 332         ac = talloc(req, struct anr_context);
 333         if (!ac) {
 334                 ldb_oom(ldb);
 335                 return LDB_ERR_OPERATIONS_ERROR;
 336         }
 337
 338         ac->module = module;
 339         ac->req = req;
 340         ac->found_anr = false;
 341
 342 #if 0
 343         printf("oldanr : %s\n", ldb_filter_from_tree (0, req->op.search.tree));
 344 #endif
 345
 346         ret = anr_replace_subtrees(ac, req->op.search.tree, "anr", &anr_tree);
 347         if (ret != LDB_SUCCESS) {
 348                 return LDB_ERR_OPERATIONS_ERROR;
 349         }
 350
 351         if (!ac->found_anr) {
 352                 talloc_free(ac);
 353                 return ldb_next_request(module, req);
 354         }
 355
 356         ret = ldb_build_search_req_ex(&down_req,
 357                                         ldb, ac,
 358                                         req->op.search.base,
 359                                         req->op.search.scope,
 360                                         anr_tree,
 361                                         req->op.search.attrs,
 362                                         req->controls,
 363                                         ac, anr_search_callback,
 364                                         req);
 365         if (ret != LDB_SUCCESS) {
 366                 return LDB_ERR_OPERATIONS_ERROR;
 367         }
 368         talloc_steal(down_req, anr_tree);
 369
 370         return ldb_next_request(module, down_req);
 371 }
 372
 373 _PUBLIC_ const struct ldb_module_ops ldb_anr_module_ops = {
 374         .name              = "anr",
 375         .search = anr_search
 376 };