source4/lib/ldb/ldb_tdb/ldb_search.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Andrew Tridgell  2004
   5
   6      ** NOTE! The following LGPL license applies to the ldb
   7      ** library. This does NOT imply that all of Samba is released
   8      ** under the LGPL
   9
  10    This library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 3 of the License, or (at your option) any later version.
  14
  15    This library is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 /*
  25  *  Name: ldb
  26  *
  27  *  Component: ldb search functions
  28  *
  29  *  Description: functions to search ldb+tdb databases
  30  *
  31  *  Author: Andrew Tridgell
  32  */
  33
  34 #include "ldb_tdb.h"
  35
  36 /*
  37   add one element to a message
  38 */
  39 static int msg_add_element(struct ldb_message *ret,
  40                            const struct ldb_message_element *el,
  41                            int check_duplicates)
  42 {
  43         unsigned int i;
  44         struct ldb_message_element *e2, *elnew;
  45
  46         if (check_duplicates && ldb_msg_find_element(ret, el->name)) {
  47                 /* its already there */
  48                 return 0;
  49         }
  50
  51         e2 = talloc_realloc(ret, ret->elements, struct ldb_message_element, ret->num_elements+1);
  52         if (!e2) {
  53                 return -1;
  54         }
  55         ret->elements = e2;
  56
  57         elnew = &e2[ret->num_elements];
  58
  59         elnew->name = talloc_strdup(ret->elements, el->name);
  60         if (!elnew->name) {
  61                 return -1;
  62         }
  63
  64         if (el->num_values) {
  65                 elnew->values = talloc_array(ret->elements, struct ldb_val, el->num_values);
  66                 if (!elnew->values) {
  67                         return -1;
  68                 }
  69         } else {
  70                 elnew->values = NULL;
  71         }
  72
  73         for (i=0;i<el->num_values;i++) {
  74                 elnew->values[i] = ldb_val_dup(elnew->values, &el->values[i]);
  75                 if (elnew->values[i].length != el->values[i].length) {
  76                         return -1;
  77                 }
  78         }
  79
  80         elnew->num_values = el->num_values;
  81
  82         ret->num_elements++;
  83
  84         return 0;
  85 }
  86
  87 /*
  88   add the special distinguishedName element
  89 */
  90 static int msg_add_distinguished_name(struct ldb_message *msg)
  91 {
  92         struct ldb_message_element el;
  93         struct ldb_val val;
  94         int ret;
  95
  96         el.flags = 0;
  97         el.name = "distinguishedName";
  98         el.num_values = 1;
  99         el.values = &val;
 100         val.data = (uint8_t *)ldb_dn_alloc_linearized(msg, msg->dn);
 101         val.length = strlen((char *)val.data);
 102
 103         ret = msg_add_element(msg, &el, 1);
 104         return ret;
 105 }
 106
 107 /*
 108   add all elements from one message into another
 109  */
 110 static int msg_add_all_elements(struct ldb_module *module, struct ldb_message *ret,
 111                                 const struct ldb_message *msg)
 112 {
 113         struct ldb_context *ldb;
 114         unsigned int i;
 115         int check_duplicates = (ret->num_elements != 0);
 116
 117         ldb = ldb_module_get_ctx(module);
 118
 119         if (msg_add_distinguished_name(ret) != 0) {
 120                 return -1;
 121         }
 122
 123         for (i=0;i<msg->num_elements;i++) {
 124                 const struct ldb_schema_attribute *a;
 125                 a = ldb_schema_attribute_by_name(ldb, msg->elements[i].name);
 126                 if (a->flags & LDB_ATTR_FLAG_HIDDEN) {
 127                         continue;
 128                 }
 129                 if (msg_add_element(ret, &msg->elements[i],
 130                                     check_duplicates) != 0) {
 131                         return -1;
 132                 }
 133         }
 134
 135         return 0;
 136 }
 137
 138
 139 /*
 140   pull the specified list of attributes from a message
 141  */
 142 static struct ldb_message *ltdb_pull_attrs(struct ldb_module *module,
 143                                            TALLOC_CTX *mem_ctx,
 144                                            const struct ldb_message *msg,
 145                                            const char * const *attrs)
 146 {
 147         struct ldb_message *ret;
 148         int i;
 149
 150         ret = talloc(mem_ctx, struct ldb_message);
 151         if (!ret) {
 152                 return NULL;
 153         }
 154
 155         ret->dn = ldb_dn_copy(ret, msg->dn);
 156         if (!ret->dn) {
 157                 talloc_free(ret);
 158                 return NULL;
 159         }
 160
 161         ret->num_elements = 0;
 162         ret->elements = NULL;
 163
 164         if (!attrs) {
 165                 if (msg_add_all_elements(module, ret, msg) != 0) {
 166                         talloc_free(ret);
 167                         return NULL;
 168                 }
 169                 return ret;
 170         }
 171
 172         for (i=0;attrs[i];i++) {
 173                 struct ldb_message_element *el;
 174
 175                 if (strcmp(attrs[i], "*") == 0) {
 176                         if (msg_add_all_elements(module, ret, msg) != 0) {
 177                                 talloc_free(ret);
 178                                 return NULL;
 179                         }
 180                         continue;
 181                 }
 182
 183                 if (ldb_attr_cmp(attrs[i], "distinguishedName") == 0) {
 184                         if (msg_add_distinguished_name(ret) != 0) {
 185                                 return NULL;
 186                         }
 187                         continue;
 188                 }
 189
 190                 el = ldb_msg_find_element(msg, attrs[i]);
 191                 if (!el) {
 192                         continue;
 193                 }
 194                 if (msg_add_element(ret, el, 1) != 0) {
 195                         talloc_free(ret);
 196                         return NULL;
 197                 }
 198         }
 199
 200         return ret;
 201 }
 202
 203 /*
 204   search the database for a single simple dn.
 205   return LDB_ERR_NO_SUCH_OBJECT on record-not-found
 206   and LDB_SUCCESS on success
 207 */
 208 static int ltdb_search_base(struct ldb_module *module, struct ldb_dn *dn)
 209 {
 210         void *data = ldb_module_get_private(module);
 211         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 212         TDB_DATA tdb_key, tdb_data;
 213
 214         if (ldb_dn_is_null(dn)) {
 215                 return LDB_ERR_NO_SUCH_OBJECT;
 216         }
 217
 218         /* form the key */
 219         tdb_key = ltdb_key(module, dn);
 220         if (!tdb_key.dptr) {
 221                 return LDB_ERR_OPERATIONS_ERROR;
 222         }
 223
 224         tdb_data = tdb_fetch(ltdb->tdb, tdb_key);
 225         talloc_free(tdb_key.dptr);
 226         if (!tdb_data.dptr) {
 227                 return LDB_ERR_NO_SUCH_OBJECT;
 228         }
 229
 230         free(tdb_data.dptr);
 231         return LDB_SUCCESS;
 232 }
 233
 234 /*
 235   search the database for a single tdb key, returning all attributes
 236   in a single message
 237
 238   return LDB_ERR_NO_SUCH_OBJECT on record-not-found
 239   and LDB_SUCCESS on success
 240 */
 241 int ltdb_search_dn1_key(struct ldb_module *module,
 242                         TDB_DATA tdb_key, struct ldb_message *msg)
 243 {
 244         void *data = ldb_module_get_private(module);
 245         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 246         int ret;
 247         TDB_DATA tdb_data;
 248
 249         memset(msg, 0, sizeof(*msg));
 250
 251         tdb_data = tdb_fetch(ltdb->tdb, tdb_key);
 252         if (!tdb_data.dptr) {
 253                 return LDB_ERR_NO_SUCH_OBJECT;
 254         }
 255
 256         msg->num_elements = 0;
 257         msg->elements = NULL;
 258
 259         ret = ltdb_unpack_data(module, &tdb_data, msg);
 260         free(tdb_data.dptr);
 261         if (ret == -1) {
 262                 struct ldb_context *ldb = ldb_module_get_ctx(module);
 263                 ldb_debug(ldb, LDB_DEBUG_ERROR, "Invalid data for index %s\n",
 264                           ldb_dn_get_linearized(msg->dn));
 265                 return LDB_ERR_OPERATIONS_ERROR;
 266         }
 267
 268         if (!msg->dn) {
 269                 return LDB_ERR_OPERATIONS_ERROR;
 270         }
 271
 272         return LDB_SUCCESS;
 273 }
 274
 275 /*
 276   search the database for a single simple dn, returning all attributes
 277   in a single message
 278
 279   return LDB_ERR_NO_SUCH_OBJECT on record-not-found
 280   and LDB_SUCCESS on success
 281 */
 282
 283 int ltdb_search_dn1(struct ldb_module *module, struct ldb_dn *dn, struct ldb_message *msg)
 284 {
 285         int ret;
 286         TDB_DATA tdb_key;
 287
 288         memset(msg, 0, sizeof(*msg));
 289
 290         /* form the key */
 291         tdb_key = ltdb_key(msg, dn);
 292         if (!tdb_key.dptr) {
 293                 return LDB_ERR_OPERATIONS_ERROR;
 294         }
 295
 296         ret = ltdb_search_dn1_key(module, tdb_key, msg);
 297         talloc_free(tdb_key.dptr);
 298         return ret;
 299 }
 300
 301 /*
 302   add a set of attributes from a record to a set of results
 303   return 0 on success, -1 on failure
 304 */
 305 int ltdb_add_attr_results(struct ldb_module *module,
 306                           TALLOC_CTX *mem_ctx,
 307                           struct ldb_message *msg,
 308                           const char * const attrs[],
 309                           unsigned int *count,
 310                           struct ldb_message ***res)
 311 {
 312         struct ldb_message *msg2;
 313         struct ldb_message **res2;
 314
 315         /* pull the attributes that the user wants */
 316         msg2 = ltdb_pull_attrs(module, mem_ctx, msg, attrs);
 317         if (!msg2) {
 318                 return -1;
 319         }
 320
 321         /* add to the results list */
 322         res2 = talloc_realloc(mem_ctx, *res, struct ldb_message *, (*count)+2);
 323         if (!res2) {
 324                 talloc_free(msg2);
 325                 return -1;
 326         }
 327
 328         (*res) = res2;
 329
 330         (*res)[*count] = talloc_move(*res, &msg2);
 331         (*res)[(*count)+1] = NULL;
 332         (*count)++;
 333
 334         return 0;
 335 }
 336
 337
 338
 339 /*
 340   filter the specified list of attributes from a message
 341   removing not requested attrs.
 342  */
 343 int ltdb_filter_attrs(struct ldb_message *msg, const char * const *attrs)
 344 {
 345         int i, keep_all = 0;
 346
 347         if (attrs) {
 348                 /* check for special attrs */
 349                 for (i = 0; attrs[i]; i++) {
 350                         if (strcmp(attrs[i], "*") == 0) {
 351                                 keep_all = 1;
 352                                 break;
 353                         }
 354
 355                         if (ldb_attr_cmp(attrs[i], "distinguishedName") == 0) {
 356                                 if (msg_add_distinguished_name(msg) != 0) {
 357                                         return -1;
 358                                 }
 359                         }
 360                 }
 361         } else {
 362                 keep_all = 1;
 363         }
 364
 365         if (keep_all) {
 366                 if (msg_add_distinguished_name(msg) != 0) {
 367                         return -1;
 368                 }
 369                 return 0;
 370         }
 371
 372         for (i = 0; i < msg->num_elements; i++) {
 373                 int j, found;
 374
 375                 for (j = 0, found = 0; attrs[j]; j++) {
 376                         if (ldb_attr_cmp(msg->elements[i].name, attrs[j]) == 0) {
 377                                 found = 1;
 378                                 break;
 379                         }
 380                 }
 381
 382                 if (!found) {
 383                         ldb_msg_remove_attr(msg, msg->elements[i].name);
 384                         i--;
 385                 }
 386         }
 387
 388         return 0;
 389 }
 390
 391 /*
 392   search function for a non-indexed search
 393  */
 394 static int search_func(struct tdb_context *tdb, TDB_DATA key, TDB_DATA data, void *state)
 395 {
 396         struct ldb_context *ldb;
 397         struct ltdb_context *ac;
 398         struct ldb_message *msg;
 399         int ret;
 400
 401         ac = talloc_get_type(state, struct ltdb_context);
 402         ldb = ldb_module_get_ctx(ac->module);
 403
 404         if (key.dsize < 4 ||
 405             strncmp((char *)key.dptr, "DN=", 3) != 0) {
 406                 return 0;
 407         }
 408
 409         msg = ldb_msg_new(ac);
 410         if (!msg) {
 411                 return -1;
 412         }
 413
 414         /* unpack the record */
 415         ret = ltdb_unpack_data(ac->module, &data, msg);
 416         if (ret == -1) {
 417                 talloc_free(msg);
 418                 return -1;
 419         }
 420
 421         /* see if it matches the given expression */
 422         if (!ldb_match_msg(ldb, msg,
 423                            ac->tree, ac->base, ac->scope)) {
 424                 talloc_free(msg);
 425                 return 0;
 426         }
 427
 428         /* filter the attributes that the user wants */
 429         ret = ltdb_filter_attrs(msg, ac->attrs);
 430
 431         if (ret == -1) {
 432                 talloc_free(msg);
 433                 return -1;
 434         }
 435
 436         ret = ldb_module_send_entry(ac->req, msg, NULL);
 437         if (ret != LDB_SUCCESS) {
 438                 ac->request_terminated = true;
 439                 /* the callback failed, abort the operation */
 440                 return -1;
 441         }
 442
 443         return 0;
 444 }
 445
 446
 447 /*
 448   search the database with a LDAP-like expression.
 449   this is the "full search" non-indexed variant
 450 */
 451 static int ltdb_search_full(struct ltdb_context *ctx)
 452 {
 453         void *data = ldb_module_get_private(ctx->module);
 454         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 455         int ret;
 456
 457         if (ltdb->in_transaction != 0) {
 458                 ret = tdb_traverse(ltdb->tdb, search_func, ctx);
 459         } else {
 460                 ret = tdb_traverse_read(ltdb->tdb, search_func, ctx);
 461         }
 462
 463         if (ret == -1) {
 464                 return LDB_ERR_OPERATIONS_ERROR;
 465         }
 466
 467         return LDB_SUCCESS;
 468 }
 469
 470 /*
 471   search the database with a LDAP-like expression.
 472   choses a search method
 473 */
 474 int ltdb_search(struct ltdb_context *ctx)
 475 {
 476         struct ldb_context *ldb;
 477         struct ldb_module *module = ctx->module;
 478         struct ldb_request *req = ctx->req;
 479         void *data = ldb_module_get_private(module);
 480         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 481         int ret;
 482
 483         ldb = ldb_module_get_ctx(module);
 484
 485         ldb_request_set_state(req, LDB_ASYNC_PENDING);
 486
 487         if (ltdb_lock_read(module) != 0) {
 488                 return LDB_ERR_OPERATIONS_ERROR;
 489         }
 490
 491         if (ltdb_cache_load(module) != 0) {
 492                 ltdb_unlock_read(module);
 493                 return LDB_ERR_OPERATIONS_ERROR;
 494         }
 495
 496         if (req->op.search.tree == NULL) {
 497                 ltdb_unlock_read(module);
 498                 return LDB_ERR_OPERATIONS_ERROR;
 499         }
 500
 501         if ((req->op.search.base == NULL) || (ldb_dn_is_null(req->op.search.base) == true)) {
 502
 503                 /* Check what we should do with a NULL dn */
 504                 switch (req->op.search.scope) {
 505                 case LDB_SCOPE_BASE:
 506                         ldb_asprintf_errstring(ldb,
 507                                                "NULL Base DN invalid for a base search");
 508                         ret = LDB_ERR_INVALID_DN_SYNTAX;
 509                         break;
 510                 case LDB_SCOPE_ONELEVEL:
 511                         ldb_asprintf_errstring(ldb,
 512                                                "NULL Base DN invalid for a one-level search");
 513                         ret = LDB_ERR_INVALID_DN_SYNTAX;
 514                         break;
 515                 case LDB_SCOPE_SUBTREE:
 516                 default:
 517                         /* We accept subtree searches from a NULL base DN, ie over the whole DB */
 518                         ret = LDB_SUCCESS;
 519                 }
 520         } else if (ldb_dn_is_valid(req->op.search.base) == false) {
 521
 522                 /* We don't want invalid base DNs here */
 523                 ldb_asprintf_errstring(ldb,
 524                                        "Invalid Base DN: %s",
 525                                        ldb_dn_get_linearized(req->op.search.base));
 526                 ret = LDB_ERR_INVALID_DN_SYNTAX;
 527
 528         } else if (ltdb->check_base) {
 529                 /* This database has been marked as 'checkBaseOnSearch', so do a spot check of the base dn */
 530                 ret = ltdb_search_base(module, req->op.search.base);
 531
 532                 if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 533                         ldb_asprintf_errstring(ldb,
 534                                                "No such Base DN: %s",
 535                                                ldb_dn_get_linearized(req->op.search.base));
 536                 }
 537
 538         } else {
 539                 /* If we are not checking the base DN life is easy */
 540                 ret = LDB_SUCCESS;
 541         }
 542
 543         ctx->tree = req->op.search.tree;
 544         ctx->scope = req->op.search.scope;
 545         ctx->base = req->op.search.base;
 546         ctx->attrs = req->op.search.attrs;
 547
 548         if (ret == LDB_SUCCESS) {
 549                 uint32_t match_count = 0;
 550
 551                 ret = ltdb_search_indexed(ctx, &match_count);
 552                 if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 553                         /* Not in the index, therefore OK! */
 554                         ret = LDB_SUCCESS;
 555
 556                 }
 557                 /* Check if we got just a normal error.
 558                  * In that case proceed to a full search unless we got a
 559                  * callback error */
 560                 if ( ! ctx->request_terminated && ret != LDB_SUCCESS) {
 561                         /* Not indexed, so we need to do a full scan */
 562 #if 0
 563                         /* useful for debugging when slow performance
 564                          * is caused by unindexed searches */
 565                         char *expression = ldb_filter_from_tree(ctx, ctx->tree);
 566                         printf("FULL SEARCH: %s\n", expression);
 567                         talloc_free(expression);
 568 #endif
 569                         if (match_count != 0) {
 570                                 /* the indexing code gave an error
 571                                  * after having returned at least one
 572                                  * entry. This means the indexes are
 573                                  * corrupt or a database record is
 574                                  * corrupt. We cannot continue with a
 575                                  * full search or we may return
 576                                  * duplicate entries
 577                                  */
 578                                 return LDB_ERR_OPERATIONS_ERROR;
 579                         }
 580                         ret = ltdb_search_full(ctx);
 581                         if (ret != LDB_SUCCESS) {
 582                                 ldb_set_errstring(ldb, "Indexed and full searches both failed!\n");
 583                         }
 584                 }
 585         }
 586
 587         ltdb_unlock_read(module);
 588
 589         return ret;
 590 }
 591