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, enum ldb_parse_op op,
  71                                        const char *attr, const DATA_BLOB *match)
  72 {
  73         struct ldb_context *ldb;
  74         struct ldb_parse_tree *match_tree;
  75
  76         ldb = ldb_module_get_ctx(module);
  77
  78         match_tree = talloc(mem_ctx, struct ldb_parse_tree);
  79
  80         /* Depending on what type of match was selected, fill in the right part of the union */
  81
  82         match_tree->operation = op;
  83         switch (op) {
  84         case LDB_OP_SUBSTRING:
  85                 match_tree->u.substring.attr = attr;
  86
  87                 match_tree->u.substring.start_with_wildcard = 0;
  88                 match_tree->u.substring.end_with_wildcard = 1;
  89                 match_tree->u.substring.chunks = talloc_array(match_tree, struct ldb_val *, 2);
  90
  91                 if (match_tree->u.substring.chunks == NULL){
  92                         talloc_free(match_tree);
  93                         ldb_oom(ldb);
  94                         return NULL;
  95                 }
  96                 match_tree->u.substring.chunks[0] = match;
  97                 match_tree->u.substring.chunks[1] = NULL;
  98                 break;
  99         case LDB_OP_EQUALITY:
 100                 match_tree->u.equality.attr = attr;
 101                 match_tree->u.equality.value = *match;
 102                 break;
 103         default:
 104                 talloc_free(match_tree);
 105                 return NULL;
 106         }
 107         return match_tree;
 108 }
 109
 110 struct anr_context {
 111         bool found_anr;
 112         struct ldb_module *module;
 113         struct ldb_request *req;
 114 };
 115
 116 /**
 117  * Given the match for an 'ambigious name resolution' query, create a
 118  * parse tree with an 'or' of all the anr attributes in the schema.
 119  */
 120
 121 /**
 122  * Callback function to do the heavy lifting for the parse tree walker
 123  */
 124 static int anr_replace_value(struct anr_context *ac,
 125                              TALLOC_CTX *mem_ctx,
 126                              const struct ldb_val *match,
 127                              struct ldb_parse_tree **ntree)
 128 {
 129         struct ldb_parse_tree *tree = NULL;
 130         struct ldb_module *module = ac->module;
 131         struct ldb_parse_tree *match_tree;
 132         struct dsdb_attribute *cur;
 133         const struct dsdb_schema *schema;
 134         struct ldb_context *ldb;
 135         uint8_t *p;
 136         enum ldb_parse_op op;
 137
 138         ldb = ldb_module_get_ctx(module);
 139
 140         schema = dsdb_get_schema(ldb);
 141         if (!schema) {
 142                 ldb_asprintf_errstring(ldb, "no schema with which to construct anr filter");
 143                 return LDB_ERR_OPERATIONS_ERROR;
 144         }
 145
 146         ac->found_anr = true;
 147
 148         if (match->length > 1 && match->data[0] == '=') {
 149                 DATA_BLOB *match2 = talloc(mem_ctx, DATA_BLOB);
 150                 *match2 = data_blob_const(match->data+1, match->length - 1);
 151                 if (match2 == NULL){
 152                         ldb_oom(ldb);
 153                         return LDB_ERR_OPERATIONS_ERROR;
 154                 }
 155                 match = match2;
 156                 op = LDB_OP_EQUALITY;
 157         } else {
 158                 op = LDB_OP_SUBSTRING;
 159         }
 160         for (cur = schema->attributes; cur; cur = cur->next) {
 161                 if (!(cur->searchFlags & SEARCH_FLAG_ANR)) continue;
 162                 match_tree = make_match_tree(module, mem_ctx, op, cur->lDAPDisplayName, match);
 163
 164                 if (tree) {
 165                         /* Inject an 'or' with the current tree */
 166                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, match_tree);
 167                         if (tree == NULL) {
 168                                 ldb_oom(ldb);
 169                                 return LDB_ERR_OPERATIONS_ERROR;
 170                         }
 171                 } else {
 172                         tree = match_tree;
 173                 }
 174         }
 175
 176
 177         /* If the search term has a space in it,
 178            split it up at the first space.  */
 179
 180         p = memchr(match->data, ' ', match->length);
 181
 182         if (p) {
 183                 struct ldb_parse_tree *first_split_filter, *second_split_filter, *split_filters, *match_tree_1, *match_tree_2;
 184                 DATA_BLOB *first_match = talloc(tree, DATA_BLOB);
 185                 DATA_BLOB *second_match = talloc(tree, DATA_BLOB);
 186                 if (!first_match || !second_match) {
 187                         ldb_oom(ldb);
 188                         return LDB_ERR_OPERATIONS_ERROR;
 189                 }
 190                 *first_match = data_blob_const(match->data, p-match->data);
 191                 *second_match = data_blob_const(p+1, match->length - (p-match->data) - 1);
 192
 193                 /* Add (|(&(givenname=first)(sn=second))(&(givenname=second)(sn=first))) */
 194
 195                 match_tree_1 = make_match_tree(module, mem_ctx, op, "givenName", first_match);
 196                 match_tree_2 = make_match_tree(module, mem_ctx, op, "sn", second_match);
 197
 198                 first_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 199                 if (first_split_filter == NULL){
 200                         ldb_oom(ldb);
 201                         return LDB_ERR_OPERATIONS_ERROR;
 202                 }
 203
 204                 match_tree_1 = make_match_tree(module, mem_ctx, op, "sn", first_match);
 205                 match_tree_2 = make_match_tree(module, mem_ctx, op, "givenName", second_match);
 206
 207                 second_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 208                 if (second_split_filter == NULL){
 209                         ldb_oom(ldb);
 210                         return LDB_ERR_OPERATIONS_ERROR;
 211                 }
 212
 213                 split_filters = make_parse_list(module, mem_ctx,  LDB_OP_OR,
 214                                                 first_split_filter, second_split_filter);
 215                 if (split_filters == NULL) {
 216                         ldb_oom(ldb);
 217                         return LDB_ERR_OPERATIONS_ERROR;
 218                 }
 219
 220                 if (tree) {
 221                         /* Inject an 'or' with the current tree */
 222                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, split_filters);
 223                 } else {
 224                         tree = split_filters;
 225                 }
 226         }
 227         *ntree = tree;
 228         return LDB_SUCCESS;
 229 }
 230
 231 /*
 232   replace any occurances of an attribute with a new, generated attribute tree
 233 */
 234 static int anr_replace_subtrees(struct anr_context *ac,
 235                                 struct ldb_parse_tree *tree,
 236                                 const char *attr,
 237                                 struct ldb_parse_tree **ntree)
 238 {
 239         int ret;
 240         int i;
 241
 242         switch (tree->operation) {
 243         case LDB_OP_AND:
 244         case LDB_OP_OR:
 245                 for (i=0;i<tree->u.list.num_elements;i++) {
 246                         ret = anr_replace_subtrees(ac, tree->u.list.elements[i],
 247                                                    attr, &tree->u.list.elements[i]);
 248                         if (ret != LDB_SUCCESS) {
 249                                 return ret;
 250                         }
 251                         *ntree = tree;
 252                 }
 253                 break;
 254         case LDB_OP_NOT:
 255                 ret = anr_replace_subtrees(ac, tree->u.isnot.child, attr, &tree->u.isnot.child);
 256                 if (ret != LDB_SUCCESS) {
 257                         return ret;
 258                 }
 259                 *ntree = tree;
 260                 break;
 261         case LDB_OP_EQUALITY:
 262                 if (ldb_attr_cmp(tree->u.equality.attr, attr) == 0) {
 263                         ret = anr_replace_value(ac, tree, &tree->u.equality.value, ntree);
 264                         if (ret != LDB_SUCCESS) {
 265                                 return ret;
 266                         }
 267                 }
 268                 break;
 269         case LDB_OP_SUBSTRING:
 270                 if (ldb_attr_cmp(tree->u.substring.attr, attr) == 0) {
 271                         if (tree->u.substring.start_with_wildcard == 0 &&
 272                             tree->u.substring.end_with_wildcard == 1 &&
 273                             tree->u.substring.chunks[0] != NULL &&
 274                             tree->u.substring.chunks[1] == NULL) {
 275                                 ret = anr_replace_value(ac, tree, tree->u.substring.chunks[0], ntree);
 276                                 if (ret != LDB_SUCCESS) {
 277                                         return ret;
 278                                 }
 279                         }
 280                 }
 281                 break;
 282         default:
 283                 break;
 284         }
 285
 286         return LDB_SUCCESS;
 287 }
 288
 289 static int anr_search_callback(struct ldb_request *req, struct ldb_reply *ares)
 290 {
 291         struct anr_context *ac;
 292
 293         ac = talloc_get_type(req->context, struct anr_context);
 294
 295         if (!ares) {
 296                 return ldb_module_done(ac->req, NULL, NULL,
 297                                         LDB_ERR_OPERATIONS_ERROR);
 298         }
 299         if (ares->error != LDB_SUCCESS) {
 300                 return ldb_module_done(ac->req, ares->controls,
 301                                         ares->response, ares->error);
 302         }
 303
 304         switch (ares->type) {
 305         case LDB_REPLY_ENTRY:
 306                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
 307
 308         case LDB_REPLY_REFERRAL:
 309                 return ldb_module_send_referral(ac->req, ares->referral);
 310
 311         case LDB_REPLY_DONE:
 312                 return ldb_module_done(ac->req, ares->controls,
 313                                         ares->response, LDB_SUCCESS);
 314
 315         }
 316         return LDB_SUCCESS;
 317 }
 318
 319 /* search */
 320 static int anr_search(struct ldb_module *module, struct ldb_request *req)
 321 {
 322         struct ldb_context *ldb;
 323         struct ldb_parse_tree *anr_tree;
 324         struct ldb_request *down_req;
 325         struct anr_context *ac;
 326         int ret;
 327
 328         ldb = ldb_module_get_ctx(module);
 329
 330         ac = talloc(req, struct anr_context);
 331         if (!ac) {
 332                 ldb_oom(ldb);
 333                 return LDB_ERR_OPERATIONS_ERROR;
 334         }
 335
 336         ac->module = module;
 337         ac->req = req;
 338         ac->found_anr = false;
 339
 340 #if 0
 341         printf("oldanr : %s\n", ldb_filter_from_tree (0, req->op.search.tree));
 342 #endif
 343
 344         ret = anr_replace_subtrees(ac, req->op.search.tree, "anr", &anr_tree);
 345         if (ret != LDB_SUCCESS) {
 346                 return LDB_ERR_OPERATIONS_ERROR;
 347         }
 348
 349         if (!ac->found_anr) {
 350                 talloc_free(ac);
 351                 return ldb_next_request(module, req);
 352         }
 353
 354         ret = ldb_build_search_req_ex(&down_req,
 355                                         ldb, ac,
 356                                         req->op.search.base,
 357                                         req->op.search.scope,
 358                                         anr_tree,
 359                                         req->op.search.attrs,
 360                                         req->controls,
 361                                         ac, anr_search_callback,
 362                                         req);
 363         if (ret != LDB_SUCCESS) {
 364                 return LDB_ERR_OPERATIONS_ERROR;
 365         }
 366         talloc_steal(down_req, anr_tree);
 367
 368         return ldb_next_request(module, down_req);
 369 }
 370
 371 _PUBLIC_ const struct ldb_module_ops ldb_anr_module_ops = {
 372         .name              = "anr",
 373         .search = anr_search
 374 };