lib/ldb/ldb_map/ldb_map_outbound.c

   1 /*
   2    ldb database mapping module
   3
   4    Copyright (C) Jelmer Vernooij 2005
   5    Copyright (C) Martin Kuehl <mkhl@samba.org> 2006
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006
   7    Copyright (C) Simo Sorce <idra@samba.org> 2008
   8
   9      ** NOTE! The following LGPL license applies to the ldb
  10      ** library. This does NOT imply that all of Samba is released
  11      ** under the LGPL
  12
  13    This library is free software; you can redistribute it and/or
  14    modify it under the terms of the GNU Lesser General Public
  15    License as published by the Free Software Foundation; either
  16    version 3 of the License, or (at your option) any later version.
  17
  18    This library is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    Lesser General Public License for more details.
  22
  23    You should have received a copy of the GNU Lesser General Public
  24    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  25
  26 */
  27
  28 #include "replace.h"
  29 #include "system/filesys.h"
  30 #include "system/time.h"
  31 #include "ldb_map.h"
  32 #include "ldb_map_private.h"
  33
  34
  35 /* Mapping attributes
  36  * ================== */
  37
  38 /* Select attributes that stay in the local partition. */
  39 static const char **map_attrs_select_local(struct ldb_module *module, void *mem_ctx, const char * const *attrs)
  40 {
  41         const struct ldb_map_context *data = map_get_context(module);
  42         const char **result;
  43         unsigned int i, last;
  44
  45         if (attrs == NULL)
  46                 return NULL;
  47
  48         last = 0;
  49         result = talloc_array(mem_ctx, const char *, 1);
  50         if (result == NULL) {
  51                 goto failed;
  52         }
  53         result[0] = NULL;
  54
  55         for (i = 0; attrs[i]; i++) {
  56                 /* Wildcards and ignored attributes are kept locally */
  57                 if ((ldb_attr_cmp(attrs[i], "*") == 0) ||
  58                     (!map_attr_check_remote(data, attrs[i]))) {
  59                         result = talloc_realloc(mem_ctx, result, const char *, last+2);
  60                         if (result == NULL) {
  61                                 goto failed;
  62                         }
  63
  64                         result[last] = talloc_strdup(result, attrs[i]);
  65                         result[last+1] = NULL;
  66                         last++;
  67                 }
  68         }
  69
  70         return result;
  71
  72 failed:
  73         talloc_free(result);
  74         map_oom(module);
  75         return NULL;
  76 }
  77
  78 /* Collect attributes that are mapped into the remote partition. */
  79 static const char **map_attrs_collect_remote(struct ldb_module *module, void *mem_ctx,
  80                                              const char * const *attrs)
  81 {
  82         const struct ldb_map_context *data = map_get_context(module);
  83         const char **result;
  84         const struct ldb_map_attribute *map;
  85         const char *name=NULL;
  86         unsigned int i, j, last;
  87         int ret;
  88
  89         last = 0;
  90         result = talloc_array(mem_ctx, const char *, 1);
  91         if (result == NULL) {
  92                 goto failed;
  93         }
  94         result[0] = NULL;
  95
  96         for (i = 0; attrs[i]; i++) {
  97                 /* Wildcards are kept remotely, too */
  98                 if (ldb_attr_cmp(attrs[i], "*") == 0) {
  99                         const char **new_attrs = NULL;
 100                         ret = map_attrs_merge(module, mem_ctx, &new_attrs, attrs);
 101                         if (ret != LDB_SUCCESS) {
 102                                 goto failed;
 103                         }
 104                         ret = map_attrs_merge(module, mem_ctx, &new_attrs, data->wildcard_attributes);
 105                         if (ret != LDB_SUCCESS) {
 106                                 goto failed;
 107                         }
 108
 109                         attrs = new_attrs;
 110                         break;
 111                 }
 112         }
 113
 114         for (i = 0; attrs[i]; i++) {
 115                 /* Wildcards are kept remotely, too */
 116                 if (ldb_attr_cmp(attrs[i], "*") == 0) {
 117                         /* Add all 'include in wildcard' attributes */
 118                         name = attrs[i];
 119                         goto named;
 120                 }
 121
 122                 /* Add remote names of mapped attrs */
 123                 map = map_attr_find_local(data, attrs[i]);
 124                 if (map == NULL) {
 125                         continue;
 126                 }
 127
 128                 switch (map->type) {
 129                 case LDB_MAP_IGNORE:
 130                         continue;
 131
 132                 case LDB_MAP_KEEP:
 133                         name = attrs[i];
 134                         goto named;
 135
 136                 case LDB_MAP_RENAME:
 137                 case LDB_MAP_RENDROP:
 138                 case LDB_MAP_CONVERT:
 139                         name = map->u.rename.remote_name;
 140                         goto named;
 141
 142                 case LDB_MAP_GENERATE:
 143                         /* Add all remote names of "generate" attrs */
 144                         for (j = 0; map->u.generate.remote_names[j]; j++) {
 145                                 result = talloc_realloc(mem_ctx, result, const char *, last+2);
 146                                 if (result == NULL) {
 147                                         goto failed;
 148                                 }
 149
 150                                 result[last] = talloc_strdup(result, map->u.generate.remote_names[j]);
 151                                 result[last+1] = NULL;
 152                                 last++;
 153                         }
 154                         continue;
 155                 }
 156
 157         named:  /* We found a single remote name, add that */
 158                 result = talloc_realloc(mem_ctx, result, const char *, last+2);
 159                 if (result == NULL) {
 160                         goto failed;
 161                 }
 162
 163                 result[last] = talloc_strdup(result, name);
 164                 result[last+1] = NULL;
 165                 last++;
 166         }
 167
 168         return result;
 169
 170 failed:
 171         talloc_free(result);
 172         map_oom(module);
 173         return NULL;
 174 }
 175
 176 /* Split attributes that stay in the local partition from those that
 177  * are mapped into the remote partition. */
 178 static int map_attrs_partition(struct ldb_module *module, void *mem_ctx, const char ***local_attrs, const char ***remote_attrs, const char * const *attrs)
 179 {
 180         *local_attrs = map_attrs_select_local(module, mem_ctx, attrs);
 181         *remote_attrs = map_attrs_collect_remote(module, mem_ctx, attrs);
 182
 183         return 0;
 184 }
 185
 186 /* Mapping message elements
 187  * ======================== */
 188
 189 /* Add an element to a message, overwriting any old identically named elements. */
 190 static int ldb_msg_replace(struct ldb_message *msg, const struct ldb_message_element *el)
 191 {
 192         struct ldb_message_element *old;
 193         unsigned j;
 194         old = ldb_msg_find_element(msg, el->name);
 195
 196         /* no local result, add as new element */
 197         if (old == NULL) {
 198                 if (ldb_msg_add_empty(msg, el->name, 0, &old) != 0) {
 199                         return LDB_ERR_OPERATIONS_ERROR;
 200                 }
 201         }
 202         else {
 203                 talloc_free(old->values);
 204         }
 205
 206         old->values = talloc_array(msg->elements, struct ldb_val, el->num_values);
 207         old->num_values = el->num_values;
 208         if (old->values == NULL) {
 209                 return LDB_ERR_OPERATIONS_ERROR;
 210         }
 211         /* copy the values into the element */
 212         for (j=0;j<el->num_values;j++) {
 213                 old->values[j] = ldb_val_dup(old->values, &el->values[j]);
 214                 if (old->values[j].data == NULL && el->values[j].length != 0) {
 215                         return LDB_ERR_OPERATIONS_ERROR;
 216                 }
 217         }
 218
 219         return 0;
 220 }
 221
 222 /* Map a message element back into the local partition. */
 223 static struct ldb_message_element *ldb_msg_el_map_remote(struct ldb_module *module,
 224                                                          void *mem_ctx,
 225                                                          const struct ldb_map_attribute *map,
 226                                                          const char *attr_name,
 227                                                          const struct ldb_message_element *old)
 228 {
 229         const struct ldb_map_context *data = map_get_context(module);
 230         const char *local_attr_name = attr_name;
 231         struct ldb_message_element *el;
 232         unsigned int i;
 233
 234         el = talloc_zero(mem_ctx, struct ldb_message_element);
 235         if (el == NULL) {
 236                 map_oom(module);
 237                 return NULL;
 238         }
 239
 240         el->values = talloc_array(el, struct ldb_val, old->num_values);
 241         if (el->values == NULL) {
 242                 talloc_free(el);
 243                 map_oom(module);
 244                 return NULL;
 245         }
 246
 247         for (i = 0; data->attribute_maps[i].local_name; i++) {
 248                 struct ldb_map_attribute *am = &data->attribute_maps[i];
 249                 if (((am->type == LDB_MAP_RENAME || am->type == LDB_MAP_RENDROP) &&
 250                         !strcmp(am->u.rename.remote_name, attr_name))
 251                     || (am->type == LDB_MAP_CONVERT &&
 252                         !strcmp(am->u.convert.remote_name, attr_name))) {
 253
 254                         local_attr_name = am->local_name;
 255                         break;
 256                 }
 257         }
 258
 259         el->name = talloc_strdup(el, local_attr_name);
 260         if (el->name == NULL) {
 261                 talloc_free(el);
 262                 map_oom(module);
 263                 return NULL;
 264         }
 265
 266         for (i = 0; i < old->num_values; i++) {
 267                 el->values[i] = ldb_val_map_remote(module, el->values, map, &old->values[i]);
 268                 /* Conversions might fail, in which case bail */
 269                 if (!el->values[i].data) {
 270                         talloc_free(el);
 271                         return NULL;
 272                 }
 273                 el->num_values++;
 274         }
 275
 276         return el;
 277 }
 278
 279 /* Merge a remote message element into a local message. */
 280 static int ldb_msg_el_merge(struct ldb_module *module, struct ldb_message *local,
 281                             struct ldb_message *remote, const char *attr_name)
 282 {
 283         const struct ldb_map_context *data = map_get_context(module);
 284         const struct ldb_map_attribute *map;
 285         struct ldb_message_element *old, *el=NULL;
 286         const char *remote_name = NULL;
 287         struct ldb_context *ldb;
 288
 289         ldb = ldb_module_get_ctx(module);
 290
 291         /* We handle wildcards in ldb_msg_el_merge_wildcard */
 292         if (ldb_attr_cmp(attr_name, "*") == 0) {
 293                 return LDB_SUCCESS;
 294         }
 295
 296         map = map_attr_find_local(data, attr_name);
 297
 298         /* Unknown attribute in remote message:
 299          * skip, attribute was probably auto-generated */
 300         if (map == NULL) {
 301                 return LDB_SUCCESS;
 302         }
 303
 304         switch (map->type) {
 305         case LDB_MAP_IGNORE:
 306                 break;
 307         case LDB_MAP_CONVERT:
 308                 remote_name = map->u.convert.remote_name;
 309                 break;
 310         case LDB_MAP_KEEP:
 311                 remote_name = attr_name;
 312                 break;
 313         case LDB_MAP_RENAME:
 314         case LDB_MAP_RENDROP:
 315                 remote_name = map->u.rename.remote_name;
 316                 break;
 317         case LDB_MAP_GENERATE:
 318                 break;
 319         }
 320
 321         switch (map->type) {
 322         case LDB_MAP_IGNORE:
 323                 return LDB_SUCCESS;
 324
 325         case LDB_MAP_CONVERT:
 326                 if (map->u.convert.convert_remote == NULL) {
 327                         ldb_debug(ldb, LDB_DEBUG_ERROR, "ldb_map: "
 328                                   "Skipping attribute '%s': "
 329                                   "'convert_remote' not set",
 330                                   attr_name);
 331                         return LDB_SUCCESS;
 332                 }
 333
 334                 FALL_THROUGH;
 335         case LDB_MAP_KEEP:
 336         case LDB_MAP_RENAME:
 337         case LDB_MAP_RENDROP:
 338                 old = ldb_msg_find_element(remote, remote_name);
 339                 if (old) {
 340                         el = ldb_msg_el_map_remote(module, local, map, attr_name, old);
 341                 } else {
 342                         return LDB_ERR_NO_SUCH_ATTRIBUTE;
 343                 }
 344                 break;
 345
 346         case LDB_MAP_GENERATE:
 347                 if (map->u.generate.generate_local == NULL) {
 348                         ldb_debug(ldb, LDB_DEBUG_ERROR, "ldb_map: "
 349                                   "Skipping attribute '%s': "
 350                                   "'generate_local' not set",
 351                                   attr_name);
 352                         return LDB_SUCCESS;
 353                 }
 354
 355                 el = map->u.generate.generate_local(module, local, attr_name, remote);
 356                 if (!el) {
 357                         /* Generation failure is probably due to lack of source attributes */
 358                         return LDB_ERR_NO_SUCH_ATTRIBUTE;
 359                 }
 360                 break;
 361         }
 362
 363         if (el == NULL) {
 364                 return LDB_ERR_NO_SUCH_ATTRIBUTE;
 365         }
 366
 367         return ldb_msg_replace(local, el);
 368 }
 369
 370 /* Handle wildcard parts of merging a remote message element into a local message. */
 371 static int ldb_msg_el_merge_wildcard(struct ldb_module *module, struct ldb_message *local,
 372                                      struct ldb_message *remote)
 373 {
 374         const struct ldb_map_context *data = map_get_context(module);
 375         const struct ldb_map_attribute *map = map_attr_find_local(data, "*");
 376         struct ldb_message_element *el=NULL;
 377         unsigned int i;
 378         int ret;
 379
 380         /* Perhaps we have a mapping for "*" */
 381         if (map && map->type == LDB_MAP_KEEP) {
 382                 /* We copy everything over, and hope that anything with a
 383                    more specific rule is overwritten */
 384                 for (i = 0; i < remote->num_elements; i++) {
 385                         el = ldb_msg_el_map_remote(module, local, map, remote->elements[i].name,
 386                                                    &remote->elements[i]);
 387                         if (el == NULL) {
 388                                 return LDB_ERR_OPERATIONS_ERROR;
 389                         }
 390
 391                         ret = ldb_msg_replace(local, el);
 392                         if (ret) {
 393                                 return ret;
 394                         }
 395                 }
 396         }
 397
 398         /* Now walk the list of possible mappings, and apply each */
 399         for (i = 0; data->attribute_maps[i].local_name; i++) {
 400                 ret = ldb_msg_el_merge(module, local, remote,
 401                                        data->attribute_maps[i].local_name);
 402                 if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
 403                         continue;
 404                 } else if (ret) {
 405                         return ret;
 406                 } else {
 407                         continue;
 408                 }
 409         }
 410
 411         return LDB_SUCCESS;
 412 }
 413
 414 /* Mapping messages
 415  * ================ */
 416
 417 /* Merge two local messages into a single one. */
 418 static int ldb_msg_merge_local(struct ldb_module *module, struct ldb_message *msg1, struct ldb_message *msg2)
 419 {
 420         unsigned int i;
 421         int ret;
 422
 423         for (i = 0; i < msg2->num_elements; i++) {
 424                 ret = ldb_msg_replace(msg1, &msg2->elements[i]);
 425                 if (ret) {
 426                         return ret;
 427                 }
 428         }
 429
 430         return LDB_SUCCESS;
 431 }
 432
 433 /* Merge a local and a remote message into a single local one. */
 434 static int ldb_msg_merge_remote(struct map_context *ac, struct ldb_message *local,
 435                                 struct ldb_message *remote)
 436 {
 437         unsigned int i;
 438         int ret;
 439         const char * const *attrs = ac->all_attrs;
 440         if (!attrs) {
 441                 ret = ldb_msg_el_merge_wildcard(ac->module, local, remote);
 442                 if (ret) {
 443                         return ret;
 444                 }
 445         }
 446
 447         for (i = 0; attrs && attrs[i]; i++) {
 448                 if (ldb_attr_cmp(attrs[i], "*") == 0) {
 449                         ret = ldb_msg_el_merge_wildcard(ac->module, local, remote);
 450                         if (ret) {
 451                                 return ret;
 452                         }
 453                         break;
 454                 }
 455         }
 456
 457         /* Try to map each attribute back;
 458          * Add to local message is possible,
 459          * Overwrite old local attribute if necessary */
 460         for (i = 0; attrs && attrs[i]; i++) {
 461                 ret = ldb_msg_el_merge(ac->module, local, remote,
 462                                        attrs[i]);
 463                 if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
 464                 } else if (ret) {
 465                         return ret;
 466                 }
 467         }
 468
 469         return LDB_SUCCESS;
 470 }
 471
 472 /* Mapping search results
 473  * ====================== */
 474
 475 /* Map a search result back into the local partition. */
 476 static int map_reply_remote(struct map_context *ac, struct ldb_reply *ares)
 477 {
 478         struct ldb_message *msg;
 479         struct ldb_dn *dn;
 480         int ret;
 481
 482         /* There is no result message, skip */
 483         if (ares->type != LDB_REPLY_ENTRY) {
 484                 return 0;
 485         }
 486
 487         /* Create a new result message */
 488         msg = ldb_msg_new(ares);
 489         if (msg == NULL) {
 490                 map_oom(ac->module);
 491                 return LDB_ERR_OPERATIONS_ERROR;
 492         }
 493
 494         /* Merge remote message into new message */
 495         ret = ldb_msg_merge_remote(ac, msg, ares->message);
 496         if (ret) {
 497                 talloc_free(msg);
 498                 return ret;
 499         }
 500
 501         /* Create corresponding local DN */
 502         dn = ldb_dn_map_rebase_remote(ac->module, msg, ares->message->dn);
 503         if (dn == NULL) {
 504                 talloc_free(msg);
 505                 return LDB_ERR_OPERATIONS_ERROR;
 506         }
 507         msg->dn = dn;
 508
 509         /* Store new message with new DN as the result */
 510         talloc_free(ares->message);
 511         ares->message = msg;
 512
 513         return 0;
 514 }
 515
 516 /* Mapping parse trees
 517  * =================== */
 518
 519 /* Check whether a parse tree can safely be split in two. */
 520 static bool ldb_parse_tree_check_splittable(const struct ldb_parse_tree *tree)
 521 {
 522         const struct ldb_parse_tree *subtree = tree;
 523         bool negate = false;
 524
 525         while (subtree) {
 526                 switch (subtree->operation) {
 527                 case LDB_OP_NOT:
 528                         negate = !negate;
 529                         subtree = subtree->u.isnot.child;
 530                         continue;
 531
 532                 case LDB_OP_AND:
 533                         return !negate; /* if negate: False */
 534
 535                 case LDB_OP_OR:
 536                         return negate;  /* if negate: True */
 537
 538                 default:
 539                         return true;    /* simple parse tree */
 540                 }
 541         }
 542
 543         return true;                    /* no parse tree */
 544 }
 545
 546 /* Collect a list of attributes required to match a given parse tree. */
 547 static int ldb_parse_tree_collect_attrs(struct ldb_module *module, void *mem_ctx, const char ***attrs, const struct ldb_parse_tree *tree)
 548 {
 549         const char **new_attrs;
 550         unsigned int i;
 551         int ret;
 552
 553         if (tree == NULL) {
 554                 return 0;
 555         }
 556
 557         switch (tree->operation) {
 558         case LDB_OP_OR:
 559         case LDB_OP_AND:                /* attributes stored in list of subtrees */
 560                 for (i = 0; i < tree->u.list.num_elements; i++) {
 561                         ret = ldb_parse_tree_collect_attrs(module, mem_ctx,
 562                                                            attrs, tree->u.list.elements[i]);
 563                         if (ret) {
 564                                 return ret;
 565                         }
 566                 }
 567                 return 0;
 568
 569         case LDB_OP_NOT:                /* attributes stored in single subtree */
 570                 return ldb_parse_tree_collect_attrs(module, mem_ctx, attrs, tree->u.isnot.child);
 571
 572         default:                        /* single attribute in tree */
 573                 new_attrs = ldb_attr_list_copy_add(mem_ctx, *attrs, tree->u.equality.attr);
 574                 talloc_free(*attrs);
 575                 *attrs = new_attrs;
 576                 return 0;
 577         }
 578 }
 579
 580 static int map_subtree_select_local(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree);
 581
 582 /* Select a negated subtree that queries attributes in the local partition */
 583 static int map_subtree_select_local_not(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 584 {
 585         struct ldb_parse_tree *child;
 586         int ret;
 587
 588         /* Prepare new tree */
 589         *new = talloc_memdup(mem_ctx, tree, sizeof(struct ldb_parse_tree));
 590         if (*new == NULL) {
 591                 map_oom(module);
 592                 return LDB_ERR_OPERATIONS_ERROR;
 593         }
 594
 595         /* Generate new subtree */
 596         ret = map_subtree_select_local(module, *new, &child, tree->u.isnot.child);
 597         if (ret) {
 598                 talloc_free(*new);
 599                 return ret;
 600         }
 601
 602         /* Prune tree without subtree */
 603         if (child == NULL) {
 604                 talloc_free(*new);
 605                 *new = NULL;
 606                 return 0;
 607         }
 608
 609         (*new)->u.isnot.child = child;
 610
 611         return ret;
 612 }
 613
 614 /* Select a list of subtrees that query attributes in the local partition */
 615 static int map_subtree_select_local_list(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 616 {
 617         unsigned int i, j;
 618         int ret=0;
 619
 620         /* Prepare new tree */
 621         *new = talloc_memdup(mem_ctx, tree, sizeof(struct ldb_parse_tree));
 622         if (*new == NULL) {
 623                 map_oom(module);
 624                 return LDB_ERR_OPERATIONS_ERROR;
 625         }
 626
 627         /* Prepare list of subtrees */
 628         (*new)->u.list.num_elements = 0;
 629         (*new)->u.list.elements = talloc_array(*new, struct ldb_parse_tree *, tree->u.list.num_elements);
 630         if ((*new)->u.list.elements == NULL) {
 631                 map_oom(module);
 632                 talloc_free(*new);
 633                 return LDB_ERR_OPERATIONS_ERROR;
 634         }
 635
 636         /* Generate new list of subtrees */
 637         j = 0;
 638         for (i = 0; i < tree->u.list.num_elements; i++) {
 639                 struct ldb_parse_tree *child = NULL;
 640                 ret = map_subtree_select_local(module, *new, &child, tree->u.list.elements[i]);
 641                 if (ret) {
 642                         talloc_free(*new);
 643                         return ret;
 644                 }
 645
 646                 if (child) {
 647                         (*new)->u.list.elements[j] = child;
 648                         j++;
 649                 }
 650         }
 651
 652         /* Prune tree without subtrees */
 653         if (j == 0) {
 654                 talloc_free(*new);
 655                 *new = NULL;
 656                 return 0;
 657         }
 658
 659         /* Fix subtree list size */
 660         (*new)->u.list.num_elements = j;
 661         (*new)->u.list.elements = talloc_realloc(*new, (*new)->u.list.elements, struct ldb_parse_tree *, (*new)->u.list.num_elements);
 662
 663         return ret;
 664 }
 665
 666 /* Select a simple subtree that queries attributes in the local partition */
 667 static int map_subtree_select_local_simple(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 668 {
 669         /* Prepare new tree */
 670         *new = talloc_memdup(mem_ctx, tree, sizeof(struct ldb_parse_tree));
 671         if (*new == NULL) {
 672                 map_oom(module);
 673                 return LDB_ERR_OPERATIONS_ERROR;
 674         }
 675
 676         return 0;
 677 }
 678
 679 /* Select subtrees that query attributes in the local partition */
 680 static int map_subtree_select_local(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 681 {
 682         const struct ldb_map_context *data = map_get_context(module);
 683
 684         if (tree == NULL) {
 685                 return 0;
 686         }
 687
 688         if (tree->operation == LDB_OP_NOT) {
 689                 return map_subtree_select_local_not(module, mem_ctx, new, tree);
 690         }
 691
 692         if (tree->operation == LDB_OP_AND || tree->operation == LDB_OP_OR) {
 693                 return map_subtree_select_local_list(module, mem_ctx, new, tree);
 694         }
 695
 696         if (map_attr_check_remote(data, tree->u.equality.attr)) {
 697                 *new = NULL;
 698                 return 0;
 699         }
 700
 701         return map_subtree_select_local_simple(module, mem_ctx, new, tree);
 702 }
 703
 704 static int map_subtree_collect_remote(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree);
 705
 706 /* Collect a negated subtree that queries attributes in the remote partition */
 707 static int map_subtree_collect_remote_not(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 708 {
 709         struct ldb_parse_tree *child;
 710         int ret;
 711
 712         /* Prepare new tree */
 713         *new = talloc_memdup(mem_ctx, tree, sizeof(struct ldb_parse_tree));
 714         if (*new == NULL) {
 715                 map_oom(module);
 716                 return LDB_ERR_OPERATIONS_ERROR;
 717         }
 718
 719         /* Generate new subtree */
 720         ret = map_subtree_collect_remote(module, *new, &child, tree->u.isnot.child);
 721         if (ret) {
 722                 talloc_free(*new);
 723                 return ret;
 724         }
 725
 726         /* Prune tree without subtree */
 727         if (child == NULL) {
 728                 talloc_free(*new);
 729                 *new = NULL;
 730                 return 0;
 731         }
 732
 733         (*new)->u.isnot.child = child;
 734
 735         return ret;
 736 }
 737
 738 /* Collect a list of subtrees that query attributes in the remote partition */
 739 static int map_subtree_collect_remote_list(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 740 {
 741         unsigned int i, j;
 742         int ret=0;
 743
 744         /* Prepare new tree */
 745         *new = talloc_memdup(mem_ctx, tree, sizeof(struct ldb_parse_tree));
 746         if (*new == NULL) {
 747                 map_oom(module);
 748                 return LDB_ERR_OPERATIONS_ERROR;
 749         }
 750
 751         /* Prepare list of subtrees */
 752         (*new)->u.list.num_elements = 0;
 753         (*new)->u.list.elements = talloc_array(*new, struct ldb_parse_tree *, tree->u.list.num_elements);
 754         if ((*new)->u.list.elements == NULL) {
 755                 map_oom(module);
 756                 talloc_free(*new);
 757                 return LDB_ERR_OPERATIONS_ERROR;
 758         }
 759
 760         /* Generate new list of subtrees */
 761         j = 0;
 762         for (i = 0; i < tree->u.list.num_elements; i++) {
 763                 struct ldb_parse_tree *child;
 764                 ret = map_subtree_collect_remote(module, *new, &child, tree->u.list.elements[i]);
 765                 if (ret) {
 766                         talloc_free(*new);
 767                         return ret;
 768                 }
 769
 770                 if (child) {
 771                         (*new)->u.list.elements[j] = child;
 772                         j++;
 773                 }
 774         }
 775
 776         /* Prune tree without subtrees */
 777         if (j == 0) {
 778                 talloc_free(*new);
 779                 *new = NULL;
 780                 return 0;
 781         }
 782
 783         /* Fix subtree list size */
 784         (*new)->u.list.num_elements = j;
 785         (*new)->u.list.elements = talloc_realloc(*new, (*new)->u.list.elements, struct ldb_parse_tree *, (*new)->u.list.num_elements);
 786
 787         return ret;
 788 }
 789
 790 /* Collect a simple subtree that queries attributes in the remote partition */
 791 int map_subtree_collect_remote_simple(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree, const struct ldb_map_attribute *map)
 792 {
 793         const char *attr;
 794
 795         /* Prepare new tree */
 796         *new = talloc(mem_ctx, struct ldb_parse_tree);
 797         if (*new == NULL) {
 798                 map_oom(module);
 799                 return LDB_ERR_OPERATIONS_ERROR;
 800         }
 801         **new = *tree;
 802
 803         if (map->type == LDB_MAP_KEEP) {
 804                 /* Nothing to do here */
 805                 return 0;
 806         }
 807
 808         /* Store attribute and value in new tree */
 809         switch (tree->operation) {
 810         case LDB_OP_PRESENT:
 811                 attr = map_attr_map_local(*new, map, tree->u.present.attr);
 812                 (*new)->u.present.attr = attr;
 813                 break;
 814         case LDB_OP_SUBSTRING:
 815         {
 816                 attr = map_attr_map_local(*new, map, tree->u.substring.attr);
 817                 (*new)->u.substring.attr = attr;
 818                 break;
 819         }
 820         case LDB_OP_EQUALITY:
 821                 attr = map_attr_map_local(*new, map, tree->u.equality.attr);
 822                 (*new)->u.equality.attr = attr;
 823                 break;
 824         case LDB_OP_LESS:
 825         case LDB_OP_GREATER:
 826         case LDB_OP_APPROX:
 827                 attr = map_attr_map_local(*new, map, tree->u.comparison.attr);
 828                 (*new)->u.comparison.attr = attr;
 829                 break;
 830         case LDB_OP_EXTENDED:
 831                 attr = map_attr_map_local(*new, map, tree->u.extended.attr);
 832                 (*new)->u.extended.attr = attr;
 833                 break;
 834         default:                        /* unknown kind of simple subtree */
 835                 talloc_free(*new);
 836                 return LDB_ERR_OPERATIONS_ERROR;
 837         }
 838
 839         if (attr == NULL) {
 840                 talloc_free(*new);
 841                 *new = NULL;
 842                 return 0;
 843         }
 844
 845         if (map->type == LDB_MAP_RENAME || map->type == LDB_MAP_RENDROP) {
 846                 /* Nothing more to do here, the attribute has been renamed */
 847                 return 0;
 848         }
 849
 850         /* Store attribute and value in new tree */
 851         switch (tree->operation) {
 852         case LDB_OP_PRESENT:
 853                 break;
 854         case LDB_OP_SUBSTRING:
 855         {
 856                 int i;
 857                 /* Map value */
 858                 (*new)->u.substring.chunks = NULL;
 859                 for (i=0; tree->u.substring.chunks && tree->u.substring.chunks[i]; i++) {
 860                         (*new)->u.substring.chunks = talloc_realloc(*new, (*new)->u.substring.chunks, struct ldb_val *, i+2);
 861                         if (!(*new)->u.substring.chunks) {
 862                                 talloc_free(*new);
 863                                 *new = NULL;
 864                                 return 0;
 865                         }
 866                         (*new)->u.substring.chunks[i] = talloc(*new, struct ldb_val);
 867                         if (!(*new)->u.substring.chunks[i]) {
 868                                 talloc_free(*new);
 869                                 *new = NULL;
 870                                 return 0;
 871                         }
 872                         *(*new)->u.substring.chunks[i] = ldb_val_map_local(module, *new, map, tree->u.substring.chunks[i]);
 873                         (*new)->u.substring.chunks[i+1] = NULL;
 874                 }
 875                 break;
 876         }
 877         case LDB_OP_EQUALITY:
 878                 (*new)->u.equality.value = ldb_val_map_local(module, *new, map, &tree->u.equality.value);
 879                 break;
 880         case LDB_OP_LESS:
 881         case LDB_OP_GREATER:
 882         case LDB_OP_APPROX:
 883                 (*new)->u.comparison.value = ldb_val_map_local(module, *new, map, &tree->u.comparison.value);
 884                 break;
 885         case LDB_OP_EXTENDED:
 886                 (*new)->u.extended.value = ldb_val_map_local(module, *new, map, &tree->u.extended.value);
 887                 (*new)->u.extended.rule_id = talloc_strdup(*new, tree->u.extended.rule_id);
 888                 break;
 889         default:                        /* unknown kind of simple subtree */
 890                 talloc_free(*new);
 891                 return LDB_ERR_OPERATIONS_ERROR;
 892         }
 893
 894         return 0;
 895 }
 896
 897 /* Collect subtrees that query attributes in the remote partition */
 898 static int map_subtree_collect_remote(struct ldb_module *module, void *mem_ctx, struct ldb_parse_tree **new, const struct ldb_parse_tree *tree)
 899 {
 900         const struct ldb_map_context *data = map_get_context(module);
 901         const struct ldb_map_attribute *map;
 902         struct ldb_context *ldb;
 903
 904         ldb = ldb_module_get_ctx(module);
 905
 906         if (tree == NULL) {
 907                 return 0;
 908         }
 909
 910         if (tree->operation == LDB_OP_NOT) {
 911                 return map_subtree_collect_remote_not(module, mem_ctx, new, tree);
 912         }
 913
 914         if ((tree->operation == LDB_OP_AND) || (tree->operation == LDB_OP_OR)) {
 915                 return map_subtree_collect_remote_list(module, mem_ctx, new, tree);
 916         }
 917
 918         if (!map_attr_check_remote(data, tree->u.equality.attr)) {
 919                 *new = NULL;
 920                 return 0;
 921         }
 922
 923         map = map_attr_find_local(data, tree->u.equality.attr);
 924         if (map->convert_operator) {
 925                 return map->convert_operator(module, mem_ctx, new, tree);
 926         }
 927
 928         if (map->type == LDB_MAP_GENERATE) {
 929                 ldb_debug(ldb, LDB_DEBUG_WARNING, "ldb_map: "
 930                           "Skipping attribute '%s': "
 931                           "'convert_operator' not set",
 932                           tree->u.equality.attr);
 933                 *new = NULL;
 934                 return 0;
 935         }
 936
 937         return map_subtree_collect_remote_simple(module, mem_ctx, new, tree, map);
 938 }
 939
 940 /* Split subtrees that query attributes in the local partition from
 941  * those that query the remote partition. */
 942 static int ldb_parse_tree_partition(struct ldb_module *module,
 943                                         void *mem_ctx,
 944                                         struct ldb_parse_tree **local_tree,
 945                                         struct ldb_parse_tree **remote_tree,
 946                                         const struct ldb_parse_tree *tree)
 947 {
 948         int ret;
 949
 950         *local_tree = NULL;
 951         *remote_tree = NULL;
 952
 953         /* No original tree */
 954         if (tree == NULL) {
 955                 return 0;
 956         }
 957
 958         /* Generate local tree */
 959         ret = map_subtree_select_local(module, mem_ctx, local_tree, tree);
 960         if (ret) {
 961                 return ret;
 962         }
 963
 964         /* Generate remote tree */
 965         ret = map_subtree_collect_remote(module, mem_ctx, remote_tree, tree);
 966         if (ret) {
 967                 talloc_free(*local_tree);
 968                 return ret;
 969         }
 970
 971         return 0;
 972 }
 973
 974 /* Collect a list of attributes required either explicitly from a
 975  * given list or implicitly  from a given parse tree; split the
 976  * collected list into local and remote parts. */
 977 static int map_attrs_collect_and_partition(struct ldb_module *module, struct map_context *ac,
 978                                            const char * const *search_attrs,
 979                                            const struct ldb_parse_tree *tree)
 980 {
 981         void *tmp_ctx;
 982         const char **tree_attrs;
 983         const char **remote_attrs;
 984         const char **local_attrs;
 985         int ret;
 986
 987         /* There is no tree, just partition the searched attributes */
 988         if (tree == NULL) {
 989                 ret = map_attrs_partition(module, ac,
 990                                           &local_attrs, &remote_attrs, search_attrs);
 991                 if (ret == 0) {
 992                         ac->local_attrs = local_attrs;
 993                         ac->remote_attrs = remote_attrs;
 994                         ac->all_attrs = search_attrs;
 995                 }
 996                 return ret;
 997         }
 998
 999         /* Create context for temporary memory */
1000         tmp_ctx = talloc_new(ac);
1001         if (tmp_ctx == NULL) {
1002                 goto oom;
1003         }
1004
1005         /* Prepare list of attributes from tree */
1006         tree_attrs = talloc_array(tmp_ctx, const char *, 1);
1007         if (tree_attrs == NULL) {
1008                 talloc_free(tmp_ctx);
1009                 goto oom;
1010         }
1011         tree_attrs[0] = NULL;
1012
1013         /* Collect attributes from tree */
1014         ret = ldb_parse_tree_collect_attrs(module, tmp_ctx, &tree_attrs, tree);
1015         if (ret) {
1016                 goto done;
1017         }
1018
1019         /* Merge attributes from search operation */
1020         ret = map_attrs_merge(module, tmp_ctx, &tree_attrs, search_attrs);
1021         if (ret) {
1022                 goto done;
1023         }
1024
1025         /* Split local from remote attributes */
1026         ret = map_attrs_partition(module, ac, &local_attrs,
1027                                   &remote_attrs, tree_attrs);
1028
1029         if (ret == 0) {
1030                 ac->local_attrs = local_attrs;
1031                 ac->remote_attrs = remote_attrs;
1032                 talloc_steal(ac, tree_attrs);
1033                 ac->all_attrs = tree_attrs;
1034         }
1035 done:
1036         /* Free temporary memory */
1037         talloc_free(tmp_ctx);
1038         return ret;
1039
1040 oom:
1041         map_oom(module);
1042         return LDB_ERR_OPERATIONS_ERROR;
1043 }
1044
1045
1046 /* Outbound requests: search
1047  * ========================= */
1048
1049 static int map_remote_search_callback(struct ldb_request *req,
1050                                         struct ldb_reply *ares);
1051 static int map_local_merge_callback(struct ldb_request *req,
1052                                         struct ldb_reply *ares);
1053 static int map_search_local(struct map_context *ac);
1054
1055 static int map_save_entry(struct map_context *ac, struct ldb_reply *ares)
1056 {
1057         struct map_reply *mr;
1058
1059         mr = talloc_zero(ac, struct map_reply);
1060         if (mr == NULL) {
1061                 map_oom(ac->module);
1062                 return LDB_ERR_OPERATIONS_ERROR;
1063         }
1064         mr->remote = talloc_steal(mr, ares);
1065         if (ac->r_current) {
1066                 ac->r_current->next = mr;
1067         } else {
1068                 /* first entry */
1069                 ac->r_list = mr;
1070         }
1071         ac->r_current = mr;
1072
1073         return LDB_SUCCESS;
1074 }
1075
1076 /* Pass a merged search result up the callback chain. */
1077 int map_return_entry(struct map_context *ac, struct ldb_reply *ares)
1078 {
1079         struct ldb_message_element *el;
1080         const char * const *attrs;
1081         struct ldb_context *ldb;
1082         unsigned int i;
1083         int ret;
1084         bool matched;
1085
1086         ldb = ldb_module_get_ctx(ac->module);
1087
1088         /* Merged result doesn't match original query, skip */
1089         ret = ldb_match_msg_error(ldb, ares->message,
1090                                   ac->req->op.search.tree,
1091                                   ac->req->op.search.base,
1092                                   ac->req->op.search.scope,
1093                                   &matched);
1094         if (ret != LDB_SUCCESS) return ret;
1095         if (!matched) {
1096                 ldb_debug(ldb, LDB_DEBUG_TRACE, "ldb_map: "
1097                           "Skipping record '%s': "
1098                           "doesn't match original search",
1099                           ldb_dn_get_linearized(ares->message->dn));
1100                 return LDB_SUCCESS;
1101         }
1102
1103         /* Limit result to requested attrs */
1104         if (ac->req->op.search.attrs &&
1105             (! ldb_attr_in_list(ac->req->op.search.attrs, "*"))) {
1106
1107                 attrs = ac->req->op.search.attrs;
1108                 i = 0;
1109
1110                 while (i < ares->message->num_elements) {
1111
1112                         el = &ares->message->elements[i];
1113                         if ( ! ldb_attr_in_list(attrs, el->name)) {
1114                                 ldb_msg_remove_element(ares->message, el);
1115                         } else {
1116                                 i++;
1117                         }
1118                 }
1119         }
1120
1121         return ldb_module_send_entry(ac->req, ares->message, ares->controls);
1122 }
1123
1124 /* Search a record. */
1125 int ldb_map_search(struct ldb_module *module, struct ldb_request *req)
1126 {
1127         struct ldb_parse_tree *remote_tree;
1128         struct ldb_parse_tree *local_tree;
1129         struct ldb_request *remote_req;
1130         struct ldb_context *ldb;
1131         struct map_context *ac;
1132         int ret;
1133
1134         const char *wildcard[] = { "*", NULL };
1135         const char * const *attrs;
1136
1137         ldb = ldb_module_get_ctx(module);
1138
1139         /* if we're not yet initialized, go to the next module */
1140         if (!ldb_module_get_private(module))
1141                 return ldb_next_request(module, req);
1142
1143         /* Do not manipulate our control entries */
1144         if (ldb_dn_is_special(req->op.search.base)) {
1145                 return ldb_next_request(module, req);
1146         }
1147
1148         /* No mapping requested, skip to next module */
1149         if ((req->op.search.base) && (!ldb_dn_check_local(module, req->op.search.base))) {
1150                 return ldb_next_request(module, req);
1151         }
1152
1153         /* TODO: How can we be sure about which partition we are
1154          *       targetting when there is no search base? */
1155
1156         /* Prepare context and handle */
1157         ac = map_init_context(module, req);
1158         if (ac == NULL) {
1159                 return LDB_ERR_OPERATIONS_ERROR;
1160         }
1161
1162         /* It is easier to deal with the two different ways of
1163          * expressing the wildcard in the same codepath */
1164         attrs = req->op.search.attrs;
1165         if (attrs == NULL) {
1166                 attrs = wildcard;
1167         }
1168
1169         /* Split local from remote attrs */
1170         ret = map_attrs_collect_and_partition(module, ac,
1171                                               attrs, req->op.search.tree);
1172         if (ret) {
1173                 return LDB_ERR_OPERATIONS_ERROR;
1174         }
1175
1176         /* Split local from remote tree */
1177         ret = ldb_parse_tree_partition(module, ac,
1178                                        &local_tree, &remote_tree,
1179                                        req->op.search.tree);
1180         if (ret) {
1181                 return LDB_ERR_OPERATIONS_ERROR;
1182         }
1183
1184         if (((local_tree != NULL) && (remote_tree != NULL)) &&
1185             (!ldb_parse_tree_check_splittable(req->op.search.tree))) {
1186                 /* The query can't safely be split, enumerate the remote partition */
1187                 local_tree = NULL;
1188                 remote_tree = NULL;
1189         }
1190
1191         if (local_tree == NULL) {
1192                 /* Construct default local parse tree */
1193                 local_tree = talloc_zero(ac, struct ldb_parse_tree);
1194                 if (local_tree == NULL) {
1195                         map_oom(ac->module);
1196                         return LDB_ERR_OPERATIONS_ERROR;
1197                 }
1198
1199                 local_tree->operation = LDB_OP_PRESENT;
1200                 local_tree->u.present.attr = talloc_strdup(local_tree, IS_MAPPED);
1201         }
1202         if (remote_tree == NULL) {
1203                 /* Construct default remote parse tree */
1204                 remote_tree = ldb_parse_tree(ac, NULL);
1205                 if (remote_tree == NULL) {
1206                         return LDB_ERR_OPERATIONS_ERROR;
1207                 }
1208         }
1209
1210         ac->local_tree = local_tree;
1211
1212         /* Prepare the remote operation */
1213         ret = ldb_build_search_req_ex(&remote_req, ldb, ac,
1214                                       req->op.search.base,
1215                                       req->op.search.scope,
1216                                       remote_tree,
1217                                       ac->remote_attrs,
1218                                       req->controls,
1219                                       ac, map_remote_search_callback,
1220                                       req);
1221         LDB_REQ_SET_LOCATION(remote_req);
1222         if (ret != LDB_SUCCESS) {
1223                 return LDB_ERR_OPERATIONS_ERROR;
1224         }
1225
1226         return ldb_next_remote_request(module, remote_req);
1227 }
1228
1229 /* Now, search the local part of a remote search result. */
1230 static int map_remote_search_callback(struct ldb_request *req,
1231                                         struct ldb_reply *ares)
1232 {
1233         struct map_context *ac;
1234         int ret;
1235
1236         ac = talloc_get_type(req->context, struct map_context);
1237
1238         if (!ares) {
1239                 return ldb_module_done(ac->req, NULL, NULL,
1240                                         LDB_ERR_OPERATIONS_ERROR);
1241         }
1242         if (ares->error != LDB_SUCCESS) {
1243                 return ldb_module_done(ac->req, ares->controls,
1244                                         ares->response, ares->error);
1245         }
1246
1247         switch (ares->type) {
1248         case LDB_REPLY_REFERRAL:
1249
1250                 /* ignore referrals */
1251                 talloc_free(ares);
1252                 return LDB_SUCCESS;
1253
1254         case LDB_REPLY_ENTRY:
1255
1256                 /* Map result record into a local message */
1257                 ret = map_reply_remote(ac, ares);
1258                 if (ret) {
1259                         talloc_free(ares);
1260                         return ldb_module_done(ac->req, NULL, NULL,
1261                                                 LDB_ERR_OPERATIONS_ERROR);
1262                 }
1263
1264                 /* if we have no local db, then we can just return the reply to
1265                  * the upper layer, otherwise we must save it and process it
1266                  * when all replies ahve been gathered */
1267                 if ( ! map_check_local_db(ac->module)) {
1268                         ret = map_return_entry(ac, ares);
1269                 } else {
1270                         ret = map_save_entry(ac,ares);
1271                 }
1272
1273                 if (ret != LDB_SUCCESS) {
1274                         talloc_free(ares);
1275                         return ldb_module_done(ac->req, NULL, NULL, ret);
1276                 }
1277                 break;
1278
1279         case LDB_REPLY_DONE:
1280
1281                 if ( ! map_check_local_db(ac->module)) {
1282                         return ldb_module_done(ac->req, ares->controls,
1283                                                 ares->response, LDB_SUCCESS);
1284                 }
1285
1286                 /* reset the pointer to the start of the list */
1287                 ac->r_current = ac->r_list;
1288
1289                 /* no entry just return */
1290                 if (ac->r_current == NULL) {
1291                         ret = ldb_module_done(ac->req, ares->controls,
1292                                                 ares->response, LDB_SUCCESS);
1293                         talloc_free(ares);
1294                         return ret;
1295                 }
1296
1297                 ac->remote_done_ares = talloc_steal(ac, ares);
1298
1299                 ret = map_search_local(ac);
1300                 if (ret != LDB_SUCCESS) {
1301                         return ldb_module_done(ac->req, NULL, NULL, ret);
1302                 }
1303         }
1304
1305         return LDB_SUCCESS;
1306 }
1307
1308 static int map_search_local(struct map_context *ac)
1309 {
1310         struct ldb_request *search_req;
1311
1312         if (ac->r_current == NULL || ac->r_current->remote == NULL) {
1313                 return LDB_ERR_OPERATIONS_ERROR;
1314         }
1315
1316         /* Prepare local search request */
1317         /* TODO: use GUIDs here instead? */
1318         search_req = map_search_base_req(ac,
1319                                          ac->r_current->remote->message->dn,
1320                                          NULL, NULL,
1321                                          ac, map_local_merge_callback);
1322         if (search_req == NULL) {
1323                 return LDB_ERR_OPERATIONS_ERROR;
1324         }
1325
1326         return ldb_next_request(ac->module, search_req);
1327 }
1328
1329 /* Merge the remote and local parts of a search result. */
1330 int map_local_merge_callback(struct ldb_request *req, struct ldb_reply *ares)
1331 {
1332         struct ldb_context *ldb;
1333         struct map_context *ac;
1334         int ret;
1335
1336         ac = talloc_get_type(req->context, struct map_context);
1337         ldb = ldb_module_get_ctx(ac->module);
1338
1339         if (!ares) {
1340                 return ldb_module_done(ac->req, NULL, NULL,
1341                                         LDB_ERR_OPERATIONS_ERROR);
1342         }
1343         if (ares->error != LDB_SUCCESS) {
1344                 return ldb_module_done(ac->req, ares->controls,
1345                                         ares->response, ares->error);
1346         }
1347
1348         switch (ares->type) {
1349         case LDB_REPLY_ENTRY:
1350                 /* We have already found a local record */
1351                 if (ac->r_current->local) {
1352                         talloc_free(ares);
1353                         ldb_set_errstring(ldb, "ldb_map: Too many results!");
1354                         return ldb_module_done(ac->req, NULL, NULL,
1355                                                 LDB_ERR_OPERATIONS_ERROR);
1356                 }
1357
1358                 /* Store local result */
1359                 ac->r_current->local = talloc_steal(ac->r_current, ares);
1360
1361                 break;
1362
1363         case LDB_REPLY_REFERRAL:
1364                 /* ignore referrals */
1365                 talloc_free(ares);
1366                 break;
1367
1368         case LDB_REPLY_DONE:
1369                 /* We don't need the local 'ares', but we will use the remote one from below */
1370                 talloc_free(ares);
1371
1372                 /* No local record found, map and send remote record */
1373                 if (ac->r_current->local != NULL) {
1374                         /* Merge remote into local message */
1375                         ret = ldb_msg_merge_local(ac->module,
1376                                                   ac->r_current->local->message,
1377                                                   ac->r_current->remote->message);
1378                         if (ret == LDB_SUCCESS) {
1379                                 ret = map_return_entry(ac, ac->r_current->local);
1380                         }
1381                         if (ret != LDB_SUCCESS) {
1382                                 return ldb_module_done(ac->req, NULL, NULL,
1383                                                         LDB_ERR_OPERATIONS_ERROR);
1384                         }
1385                 } else {
1386                         ret = map_return_entry(ac, ac->r_current->remote);
1387                         if (ret != LDB_SUCCESS) {
1388                                 return ldb_module_done(ac->req,
1389                                                         NULL, NULL, ret);
1390                         }
1391                 }
1392
1393                 if (ac->r_current->next != NULL) {
1394                         ac->r_current = ac->r_current->next;
1395                         if (ac->r_current->remote->type == LDB_REPLY_ENTRY) {
1396                                 ret = map_search_local(ac);
1397                                 if (ret != LDB_SUCCESS) {
1398                                         return ldb_module_done(ac->req,
1399                                                                NULL, NULL, ret);
1400                                 }
1401                                 break;
1402                         }
1403                 }
1404
1405                 /* ok we are done with all search, finally it is time to
1406                  * finish operations for this module */
1407                 return ldb_module_done(ac->req,
1408                                         ac->remote_done_ares->controls,
1409                                         ac->remote_done_ares->response,
1410                                         ac->remote_done_ares->error);
1411         }
1412
1413         return LDB_SUCCESS;
1414 }