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