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_includes.h"
  34 #include "dsdb/samdb/samdb.h"
  35
  36 /**
  37  * Make a and 'and' or 'or' tree from the two supplied elements
  38  */
  39 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_parse_tree *list;
  44
  45         list = talloc(mem_ctx, struct ldb_parse_tree);
  46         if (list == NULL){
  47                 ldb_oom(module->ldb);
  48                 return NULL;
  49         }
  50         list->operation = op;
  51
  52         list->u.list.num_elements = 2;
  53         list->u.list.elements = talloc_array(list, struct ldb_parse_tree *, 2);
  54         if (!list->u.list.elements) {
  55                 ldb_oom(module->ldb);
  56                 return NULL;
  57         }
  58         list->u.list.elements[0] = talloc_steal(list, first_arm);
  59         list->u.list.elements[1] = talloc_steal(list, second_arm);
  60         return list;
  61 }
  62
  63 /**
  64  * Make an equality or prefix match tree, from the attribute, operation and matching value supplied
  65  */
  66 struct ldb_parse_tree *make_match_tree(struct ldb_module *module,
  67                                        TALLOC_CTX *mem_ctx, enum ldb_parse_op op,
  68                                        const char *attr, const DATA_BLOB *match)
  69 {
  70         struct ldb_parse_tree *match_tree;
  71
  72         match_tree = talloc(mem_ctx, struct ldb_parse_tree);
  73
  74         /* Depending on what type of match was selected, fill in the right part of the union */
  75
  76         match_tree->operation = op;
  77         switch (op) {
  78         case LDB_OP_SUBSTRING:
  79                 match_tree->u.substring.attr = attr;
  80
  81                 match_tree->u.substring.start_with_wildcard = 0;
  82                 match_tree->u.substring.end_with_wildcard = 1;
  83                 match_tree->u.substring.chunks = talloc_array(match_tree, struct ldb_val *, 2);
  84
  85                 if (match_tree->u.substring.chunks == NULL){
  86                         ldb_oom(module->ldb);
  87                         return NULL;
  88                 }
  89                 match_tree->u.substring.chunks[0] = match;
  90                 match_tree->u.substring.chunks[1] = NULL;
  91                 break;
  92         case LDB_OP_EQUALITY:
  93                 match_tree->u.equality.attr = attr;
  94                 match_tree->u.equality.value = *match;
  95                 break;
  96         }
  97         return match_tree;
  98 }
  99
 100 struct anr_context {
 101         bool found_anr;
 102         struct ldb_module *module;
 103         struct ldb_request *req;
 104 };
 105
 106 /**
 107  * Given the match for an 'ambigious name resolution' query, create a
 108  * parse tree with an 'or' of all the anr attributes in the schema.
 109  */
 110
 111 /**
 112  * Callback function to do the heavy lifting for the parse tree walker
 113  */
 114 static int anr_replace_value(struct anr_context *ac,
 115                              TALLOC_CTX *mem_ctx,
 116                              const struct ldb_val *match,
 117                              struct ldb_parse_tree **ntree)
 118 {
 119         struct ldb_parse_tree *tree = NULL;
 120         struct ldb_module *module = ac->module;
 121         struct ldb_parse_tree *match_tree;
 122         struct dsdb_attribute *cur;
 123         const struct dsdb_schema *schema = dsdb_get_schema(module->ldb);
 124         uint8_t *p;
 125         enum ldb_parse_op op;
 126
 127         if (!schema) {
 128                 ldb_asprintf_errstring(module->ldb, "no schema with which to construct anr filter");
 129                 return LDB_ERR_OPERATIONS_ERROR;
 130         }
 131
 132         ac->found_anr = true;
 133
 134         if (match->length > 1 && match->data[0] == '=') {
 135                 DATA_BLOB *match2 = talloc(mem_ctx, DATA_BLOB);
 136                 *match2 = data_blob_const(match->data+1, match->length - 1);
 137                 if (match2 == NULL){
 138                         ldb_oom(module->ldb);
 139                         return LDB_ERR_OPERATIONS_ERROR;
 140                 }
 141                 match = match2;
 142                 op = LDB_OP_EQUALITY;
 143         } else {
 144                 op = LDB_OP_SUBSTRING;
 145         }
 146         for (cur = schema->attributes; cur; cur = cur->next) {
 147                 if (!(cur->searchFlags & SEARCH_FLAG_ANR)) continue;
 148                 match_tree = make_match_tree(module, mem_ctx, op, cur->lDAPDisplayName, match);
 149
 150                 if (tree) {
 151                         /* Inject an 'or' with the current tree */
 152                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, match_tree);
 153                         if (tree == NULL) {
 154                                 ldb_oom(module->ldb);
 155                                 return LDB_ERR_OPERATIONS_ERROR;
 156                         }
 157                 } else {
 158                         tree = match_tree;
 159                 }
 160         }
 161
 162
 163         /* If the search term has a space in it,
 164            split it up at the first space.  */
 165
 166         p = memchr(match->data, ' ', match->length);
 167
 168         if (p) {
 169                 struct ldb_parse_tree *first_split_filter, *second_split_filter, *split_filters, *match_tree_1, *match_tree_2;
 170                 DATA_BLOB *first_match = talloc(tree, DATA_BLOB);
 171                 DATA_BLOB *second_match = talloc(tree, DATA_BLOB);
 172                 if (!first_match || !second_match) {
 173                         ldb_oom(module->ldb);
 174                         return LDB_ERR_OPERATIONS_ERROR;
 175                 }
 176                 *first_match = data_blob_const(match->data, p-match->data);
 177                 *second_match = data_blob_const(p+1, match->length - (p-match->data) - 1);
 178
 179                 /* Add (|(&(givenname=first)(sn=second))(&(givenname=second)(sn=first))) */
 180
 181                 match_tree_1 = make_match_tree(module, mem_ctx, op, "givenName", first_match);
 182                 match_tree_2 = make_match_tree(module, mem_ctx, op, "sn", second_match);
 183
 184                 first_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 185                 if (first_split_filter == NULL){
 186                         ldb_oom(module->ldb);
 187                         return LDB_ERR_OPERATIONS_ERROR;
 188                 }
 189
 190                 match_tree_1 = make_match_tree(module, mem_ctx, op, "sn", first_match);
 191                 match_tree_2 = make_match_tree(module, mem_ctx, op, "givenName", second_match);
 192
 193                 second_split_filter = make_parse_list(module, ac,  LDB_OP_AND, match_tree_1, match_tree_2);
 194                 if (second_split_filter == NULL){
 195                         ldb_oom(module->ldb);
 196                         return LDB_ERR_OPERATIONS_ERROR;
 197                 }
 198
 199                 split_filters = make_parse_list(module, mem_ctx,  LDB_OP_OR,
 200                                                 first_split_filter, second_split_filter);
 201                 if (split_filters == NULL) {
 202                         ldb_oom(module->ldb);
 203                         return LDB_ERR_OPERATIONS_ERROR;
 204                 }
 205
 206                 if (tree) {
 207                         /* Inject an 'or' with the current tree */
 208                         tree = make_parse_list(module, mem_ctx,  LDB_OP_OR, tree, split_filters);
 209                 } else {
 210                         tree = split_filters;
 211                 }
 212         }
 213         *ntree = tree;
 214         return LDB_SUCCESS;
 215 }
 216
 217 /*
 218   replace any occurances of an attribute with a new, generated attribute tree
 219 */
 220 static int anr_replace_subtrees(struct anr_context *ac,
 221                                 struct ldb_parse_tree *tree,
 222                                 const char *attr,
 223                                 struct ldb_parse_tree **ntree)
 224 {
 225         int ret;
 226         int i;
 227
 228         switch (tree->operation) {
 229         case LDB_OP_AND:
 230         case LDB_OP_OR:
 231                 for (i=0;i<tree->u.list.num_elements;i++) {
 232                         ret = anr_replace_subtrees(ac, tree->u.list.elements[i],
 233                                                    attr, &tree->u.list.elements[i]);
 234                         if (ret != LDB_SUCCESS) {
 235                                 return ret;
 236                         }
 237                         *ntree = tree;
 238                 }
 239                 break;
 240         case LDB_OP_NOT:
 241                 ret = anr_replace_subtrees(ac, tree->u.isnot.child, attr, &tree->u.isnot.child);
 242                 if (ret != LDB_SUCCESS) {
 243                         return ret;
 244                 }
 245                 *ntree = tree;
 246                 break;
 247         case LDB_OP_EQUALITY:
 248                 if (ldb_attr_cmp(tree->u.equality.attr, attr) == 0) {
 249                         ret = anr_replace_value(ac, tree, &tree->u.equality.value, ntree);
 250                         if (ret != LDB_SUCCESS) {
 251                                 return ret;
 252                         }
 253                 }
 254                 break;
 255         case LDB_OP_SUBSTRING:
 256                 if (ldb_attr_cmp(tree->u.substring.attr, attr) == 0) {
 257                         if (tree->u.substring.start_with_wildcard == 0 &&
 258                             tree->u.substring.end_with_wildcard == 1 &&
 259                             tree->u.substring.chunks[0] != NULL &&
 260                             tree->u.substring.chunks[1] == NULL) {
 261                                 ret = anr_replace_value(ac, tree, tree->u.substring.chunks[0], ntree);
 262                                 if (ret != LDB_SUCCESS) {
 263                                         return ret;
 264                                 }
 265                         }
 266                 }
 267                 break;
 268         default:
 269                 break;
 270         }
 271
 272         return LDB_SUCCESS;
 273 }
 274
 275 static int anr_search_callback(struct ldb_request *req, struct ldb_reply *ares)
 276 {
 277         struct anr_context *ac;
 278
 279         ac = talloc_get_type(req->context, struct anr_context);
 280
 281         if (!ares) {
 282                 return ldb_module_done(ac->req, NULL, NULL,
 283                                         LDB_ERR_OPERATIONS_ERROR);
 284         }
 285         if (ares->error != LDB_SUCCESS) {
 286                 return ldb_module_done(ac->req, ares->controls,
 287                                         ares->response, ares->error);
 288         }
 289
 290         switch (ares->type) {
 291         case LDB_REPLY_ENTRY:
 292                 return ldb_module_send_entry(ac->req, ares->message);
 293
 294         case LDB_REPLY_REFERRAL:
 295                 return ldb_module_send_referral(ac->req, ares->referral);
 296
 297         case LDB_REPLY_DONE:
 298                 return ldb_module_done(ac->req, ares->controls,
 299                                         ares->response, LDB_SUCCESS);
 300
 301         }
 302         return LDB_SUCCESS;
 303 }
 304
 305 /* search */
 306 static int anr_search(struct ldb_module *module, struct ldb_request *req)
 307 {
 308         struct ldb_parse_tree *anr_tree;
 309         struct ldb_request *down_req;
 310         struct anr_context *ac;
 311         int ret;
 312
 313         ac = talloc(req, struct anr_context);
 314         if (!ac) {
 315                 ldb_oom(module->ldb);
 316                 return LDB_ERR_OPERATIONS_ERROR;
 317         }
 318
 319         ac->module = module;
 320         ac->req = req;
 321         ac->found_anr = false;
 322
 323 #if 0
 324         printf("oldanr : %s\n", ldb_filter_from_tree (0, req->op.search.tree));
 325 #endif
 326
 327         ret = anr_replace_subtrees(ac, req->op.search.tree, "anr", &anr_tree);
 328         if (ret != LDB_SUCCESS) {
 329                 return LDB_ERR_OPERATIONS_ERROR;
 330         }
 331
 332         if (!ac->found_anr) {
 333                 talloc_free(ac);
 334                 return ldb_next_request(module, req);
 335         }
 336
 337         ret = ldb_build_search_req_ex(&down_req,
 338                                         module->ldb, ac,
 339                                         req->op.search.base,
 340                                         req->op.search.scope,
 341                                         anr_tree,
 342                                         req->op.search.attrs,
 343                                         req->controls,
 344                                         ac, anr_search_callback,
 345                                         req);
 346         if (ret != LDB_SUCCESS) {
 347                 return LDB_ERR_OPERATIONS_ERROR;
 348         }
 349         talloc_steal(down_req, anr_tree);
 350
 351         return ldb_next_request(module, down_req);
 352 }
 353
 354 _PUBLIC_ const struct ldb_module_ops ldb_anr_module_ops = {
 355         .name              = "anr",
 356         .search = anr_search
 357 };