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 #include "ldb_private.h"
  36 #include <tdb.h>
  37
  38 /*
  39   add one element to a message
  40 */
  41 static int msg_add_element(struct ldb_message *ret,
  42                            const struct ldb_message_element *el,
  43                            int check_duplicates)
  44 {
  45         unsigned int i;
  46         struct ldb_message_element *e2, *elnew;
  47
  48         if (check_duplicates && ldb_msg_find_element(ret, el->name)) {
  49                 /* its already there */
  50                 return 0;
  51         }
  52
  53         e2 = talloc_realloc(ret, ret->elements, struct ldb_message_element, ret->num_elements+1);
  54         if (!e2) {
  55                 return -1;
  56         }
  57         ret->elements = e2;
  58
  59         elnew = &e2[ret->num_elements];
  60
  61         elnew->name = talloc_strdup(ret->elements, el->name);
  62         if (!elnew->name) {
  63                 return -1;
  64         }
  65
  66         if (el->num_values) {
  67                 elnew->values = talloc_array(ret->elements, struct ldb_val, el->num_values);
  68                 if (!elnew->values) {
  69                         return -1;
  70                 }
  71         } else {
  72                 elnew->values = NULL;
  73         }
  74
  75         for (i=0;i<el->num_values;i++) {
  76                 elnew->values[i] = ldb_val_dup(elnew->values, &el->values[i]);
  77                 if (elnew->values[i].length != el->values[i].length) {
  78                         return -1;
  79                 }
  80         }
  81
  82         elnew->num_values = el->num_values;
  83         elnew->flags = el->flags;
  84
  85         ret->num_elements++;
  86
  87         return 0;
  88 }
  89
  90 /*
  91   add the special distinguishedName element
  92 */
  93 static int msg_add_distinguished_name(struct ldb_message *msg)
  94 {
  95         struct ldb_message_element el;
  96         struct ldb_val val;
  97         int ret;
  98
  99         el.flags = 0;
 100         el.name = "distinguishedName";
 101         el.num_values = 1;
 102         el.values = &val;
 103         el.flags = 0;
 104         val.data = (uint8_t *)ldb_dn_alloc_linearized(msg, msg->dn);
 105         val.length = strlen((char *)val.data);
 106
 107         ret = msg_add_element(msg, &el, 1);
 108         return ret;
 109 }
 110
 111 /*
 112   add all elements from one message into another
 113  */
 114 static int msg_add_all_elements(struct ldb_module *module, struct ldb_message *ret,
 115                                 const struct ldb_message *msg)
 116 {
 117         struct ldb_context *ldb;
 118         unsigned int i;
 119         int check_duplicates = (ret->num_elements != 0);
 120
 121         ldb = ldb_module_get_ctx(module);
 122
 123         if (msg_add_distinguished_name(ret) != 0) {
 124                 return -1;
 125         }
 126
 127         for (i=0;i<msg->num_elements;i++) {
 128                 const struct ldb_schema_attribute *a;
 129                 a = ldb_schema_attribute_by_name(ldb, msg->elements[i].name);
 130                 if (a->flags & LDB_ATTR_FLAG_HIDDEN) {
 131                         continue;
 132                 }
 133                 if (msg_add_element(ret, &msg->elements[i],
 134                                     check_duplicates) != 0) {
 135                         return -1;
 136                 }
 137         }
 138
 139         return 0;
 140 }
 141
 142
 143 /*
 144   pull the specified list of attributes from a message
 145  */
 146 static struct ldb_message *ltdb_pull_attrs(struct ldb_module *module,
 147                                            TALLOC_CTX *mem_ctx,
 148                                            const struct ldb_message *msg,
 149                                            const char * const *attrs)
 150 {
 151         struct ldb_message *ret;
 152         unsigned int i;
 153
 154         ret = talloc(mem_ctx, struct ldb_message);
 155         if (!ret) {
 156                 return NULL;
 157         }
 158
 159         ret->dn = ldb_dn_copy(ret, msg->dn);
 160         if (!ret->dn) {
 161                 talloc_free(ret);
 162                 return NULL;
 163         }
 164
 165         ret->num_elements = 0;
 166         ret->elements = NULL;
 167
 168         if (!attrs) {
 169                 if (msg_add_all_elements(module, ret, msg) != 0) {
 170                         talloc_free(ret);
 171                         return NULL;
 172                 }
 173                 return ret;
 174         }
 175
 176         for (i=0;attrs[i];i++) {
 177                 struct ldb_message_element *el;
 178
 179                 if (strcmp(attrs[i], "*") == 0) {
 180                         if (msg_add_all_elements(module, ret, msg) != 0) {
 181                                 talloc_free(ret);
 182                                 return NULL;
 183                         }
 184                         continue;
 185                 }
 186
 187                 if (ldb_attr_cmp(attrs[i], "distinguishedName") == 0) {
 188                         if (msg_add_distinguished_name(ret) != 0) {
 189                                 return NULL;
 190                         }
 191                         continue;
 192                 }
 193
 194                 el = ldb_msg_find_element(msg, attrs[i]);
 195                 if (!el) {
 196                         continue;
 197                 }
 198                 if (msg_add_element(ret, el, 1) != 0) {
 199                         talloc_free(ret);
 200                         return NULL;
 201                 }
 202         }
 203
 204         return ret;
 205 }
 206
 207 /*
 208   search the database for a single simple dn.
 209   return LDB_ERR_NO_SUCH_OBJECT on record-not-found
 210   and LDB_SUCCESS on success
 211 */
 212 static int ltdb_search_base(struct ldb_module *module, struct ldb_dn *dn)
 213 {
 214         void *data = ldb_module_get_private(module);
 215         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 216         TDB_DATA tdb_key;
 217         int exists;
 218
 219         if (ldb_dn_is_null(dn)) {
 220                 return LDB_ERR_NO_SUCH_OBJECT;
 221         }
 222
 223         /* form the key */
 224         tdb_key = ltdb_key(module, dn);
 225         if (!tdb_key.dptr) {
 226                 return LDB_ERR_OPERATIONS_ERROR;
 227         }
 228
 229         exists = tdb_exists(ltdb->tdb, tdb_key);
 230         talloc_free(tdb_key.dptr);
 231
 232         if (exists) {
 233                 return LDB_SUCCESS;
 234         }
 235         return LDB_ERR_NO_SUCH_OBJECT;
 236 }
 237
 238 struct ltdb_parse_data_unpack_ctx {
 239         struct ldb_message *msg;
 240         struct ldb_module *module;
 241 };
 242
 243 static int ltdb_parse_data_unpack(TDB_DATA key, TDB_DATA data,
 244                                   void *private_data)
 245 {
 246         struct ltdb_parse_data_unpack_ctx *ctx = private_data;
 247
 248         struct ldb_context *ldb = ldb_module_get_ctx(ctx->module);
 249         int ret = ldb_unpack_data(ldb, (struct ldb_val *)&data, ctx->msg);
 250         if (ret == -1) {
 251                 ldb_debug(ldb, LDB_DEBUG_ERROR, "Invalid data for index %*.*s\n",
 252                           (int)key.dsize, (int)key.dsize, key.dptr);
 253                 return LDB_ERR_OPERATIONS_ERROR;
 254         }
 255         return ret;
 256 }
 257
 258 /*
 259   search the database for a single simple dn, returning all attributes
 260   in a single message
 261
 262   return LDB_ERR_NO_SUCH_OBJECT on record-not-found
 263   and LDB_SUCCESS on success
 264 */
 265 int ltdb_search_dn1(struct ldb_module *module, struct ldb_dn *dn, struct ldb_message *msg)
 266 {
 267         void *data = ldb_module_get_private(module);
 268         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 269         int ret;
 270         TDB_DATA tdb_key;
 271         struct ltdb_parse_data_unpack_ctx ctx = {
 272                 .msg = msg,
 273                 .module = module
 274         };
 275
 276         /* form the key */
 277         tdb_key = ltdb_key(module, dn);
 278         if (!tdb_key.dptr) {
 279                 return LDB_ERR_OPERATIONS_ERROR;
 280         }
 281
 282         memset(msg, 0, sizeof(*msg));
 283
 284         msg->num_elements = 0;
 285         msg->elements = NULL;
 286
 287         ret = tdb_parse_record(ltdb->tdb, tdb_key,
 288                                ltdb_parse_data_unpack, &ctx);
 289         talloc_free(tdb_key.dptr);
 290
 291         if (ret == -1) {
 292                 if (tdb_error(ltdb->tdb) == TDB_ERR_NOEXIST) {
 293                         return LDB_ERR_NO_SUCH_OBJECT;
 294                 }
 295                 return LDB_ERR_OPERATIONS_ERROR;
 296         } else if (ret != LDB_SUCCESS) {
 297                 return ret;
 298         }
 299
 300         if (!msg->dn) {
 301                 msg->dn = ldb_dn_copy(msg, dn);
 302         }
 303         if (!msg->dn) {
 304                 return LDB_ERR_OPERATIONS_ERROR;
 305         }
 306
 307         return LDB_SUCCESS;
 308 }
 309
 310 /*
 311   add a set of attributes from a record to a set of results
 312   return 0 on success, -1 on failure
 313 */
 314 int ltdb_add_attr_results(struct ldb_module *module,
 315                           TALLOC_CTX *mem_ctx,
 316                           struct ldb_message *msg,
 317                           const char * const attrs[],
 318                           unsigned int *count,
 319                           struct ldb_message ***res)
 320 {
 321         struct ldb_message *msg2;
 322         struct ldb_message **res2;
 323
 324         /* pull the attributes that the user wants */
 325         msg2 = ltdb_pull_attrs(module, mem_ctx, msg, attrs);
 326         if (!msg2) {
 327                 return -1;
 328         }
 329
 330         /* add to the results list */
 331         res2 = talloc_realloc(mem_ctx, *res, struct ldb_message *, (*count)+2);
 332         if (!res2) {
 333                 talloc_free(msg2);
 334                 return -1;
 335         }
 336
 337         (*res) = res2;
 338
 339         (*res)[*count] = talloc_move(*res, &msg2);
 340         (*res)[(*count)+1] = NULL;
 341         (*count)++;
 342
 343         return 0;
 344 }
 345
 346
 347
 348 /*
 349   filter the specified list of attributes from a message
 350   removing not requested attrs.
 351  */
 352 int ltdb_filter_attrs(struct ldb_message *msg, const char * const *attrs)
 353 {
 354         unsigned int i;
 355         int keep_all = 0;
 356         struct ldb_message_element *el2;
 357         uint32_t num_elements;
 358
 359         if (attrs) {
 360                 /* check for special attrs */
 361                 for (i = 0; attrs[i]; i++) {
 362                         if (strcmp(attrs[i], "*") == 0) {
 363                                 keep_all = 1;
 364                                 break;
 365                         }
 366
 367                         if (ldb_attr_cmp(attrs[i], "distinguishedName") == 0) {
 368                                 if (msg_add_distinguished_name(msg) != 0) {
 369                                         return -1;
 370                                 }
 371                         }
 372                 }
 373         } else {
 374                 keep_all = 1;
 375         }
 376
 377         if (keep_all) {
 378                 if (msg_add_distinguished_name(msg) != 0) {
 379                         return -1;
 380                 }
 381                 return 0;
 382         }
 383
 384         el2 = talloc_array(msg, struct ldb_message_element, msg->num_elements);
 385         if (el2 == NULL) {
 386                 return -1;
 387         }
 388         num_elements = 0;
 389
 390         for (i = 0; i < msg->num_elements; i++) {
 391                 unsigned int j;
 392                 int found = 0;
 393
 394                 for (j = 0; attrs[j]; j++) {
 395                         if (ldb_attr_cmp(msg->elements[i].name, attrs[j]) == 0) {
 396                                 found = 1;
 397                                 break;
 398                         }
 399                 }
 400
 401                 if (found) {
 402                         el2[num_elements] = msg->elements[i];
 403                         talloc_steal(el2, el2[num_elements].name);
 404                         talloc_steal(el2, el2[num_elements].values);
 405                         num_elements++;
 406                 }
 407         }
 408
 409         talloc_free(msg->elements);
 410
 411         if (num_elements > 0) {
 412                 msg->elements = talloc_realloc(msg, el2, struct ldb_message_element,
 413                                                num_elements);
 414         } else {
 415                 msg->elements = talloc_array(msg, struct ldb_message_element, 0);
 416                 talloc_free(el2);
 417         }
 418         if (msg->elements == NULL) {
 419                 return -1;
 420         }
 421
 422         msg->num_elements = num_elements;
 423
 424         return 0;
 425 }
 426
 427 /*
 428   search function for a non-indexed search
 429  */
 430 static int search_func(struct tdb_context *tdb, TDB_DATA key, TDB_DATA data, void *state)
 431 {
 432         struct ldb_context *ldb;
 433         struct ltdb_context *ac;
 434         struct ldb_message *msg;
 435         int ret;
 436         bool matched;
 437
 438         ac = talloc_get_type(state, struct ltdb_context);
 439         ldb = ldb_module_get_ctx(ac->module);
 440
 441         if (key.dsize < 4 ||
 442             strncmp((char *)key.dptr, "DN=", 3) != 0) {
 443                 return 0;
 444         }
 445
 446         msg = ldb_msg_new(ac);
 447         if (!msg) {
 448                 ac->error = LDB_ERR_OPERATIONS_ERROR;
 449                 return -1;
 450         }
 451
 452         /* unpack the record */
 453         ret = ldb_unpack_data(ldb, (struct ldb_val *)&data, msg);
 454         if (ret == -1) {
 455                 talloc_free(msg);
 456                 ac->error = LDB_ERR_OPERATIONS_ERROR;
 457                 return -1;
 458         }
 459
 460         if (!msg->dn) {
 461                 msg->dn = ldb_dn_new(msg, ldb,
 462                                      (char *)key.dptr + 3);
 463                 if (msg->dn == NULL) {
 464                         talloc_free(msg);
 465                         ac->error = LDB_ERR_OPERATIONS_ERROR;
 466                         return -1;
 467                 }
 468         }
 469
 470         /* see if it matches the given expression */
 471         ret = ldb_match_msg_error(ldb, msg,
 472                                   ac->tree, ac->base, ac->scope, &matched);
 473         if (ret != LDB_SUCCESS) {
 474                 talloc_free(msg);
 475                 ac->error = LDB_ERR_OPERATIONS_ERROR;
 476                 return -1;
 477         }
 478         if (!matched) {
 479                 talloc_free(msg);
 480                 return 0;
 481         }
 482
 483         /* filter the attributes that the user wants */
 484         ret = ltdb_filter_attrs(msg, ac->attrs);
 485
 486         if (ret == -1) {
 487                 talloc_free(msg);
 488                 ac->error = LDB_ERR_OPERATIONS_ERROR;
 489                 return -1;
 490         }
 491
 492         ret = ldb_module_send_entry(ac->req, msg, NULL);
 493         if (ret != LDB_SUCCESS) {
 494                 ac->request_terminated = true;
 495                 /* the callback failed, abort the operation */
 496                 ac->error = LDB_ERR_OPERATIONS_ERROR;
 497                 return -1;
 498         }
 499
 500         return 0;
 501 }
 502
 503
 504 /*
 505   search the database with a LDAP-like expression.
 506   this is the "full search" non-indexed variant
 507 */
 508 static int ltdb_search_full(struct ltdb_context *ctx)
 509 {
 510         void *data = ldb_module_get_private(ctx->module);
 511         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 512         int ret;
 513
 514         ctx->error = LDB_SUCCESS;
 515         if (ltdb->in_transaction != 0) {
 516                 ret = tdb_traverse(ltdb->tdb, search_func, ctx);
 517         } else {
 518                 ret = tdb_traverse_read(ltdb->tdb, search_func, ctx);
 519         }
 520
 521         if (ret < 0) {
 522                 return LDB_ERR_OPERATIONS_ERROR;
 523         }
 524
 525         return ctx->error;
 526 }
 527
 528 /*
 529   search the database with a LDAP-like expression.
 530   choses a search method
 531 */
 532 int ltdb_search(struct ltdb_context *ctx)
 533 {
 534         struct ldb_context *ldb;
 535         struct ldb_module *module = ctx->module;
 536         struct ldb_request *req = ctx->req;
 537         void *data = ldb_module_get_private(module);
 538         struct ltdb_private *ltdb = talloc_get_type(data, struct ltdb_private);
 539         int ret;
 540
 541         ldb = ldb_module_get_ctx(module);
 542
 543         ldb_request_set_state(req, LDB_ASYNC_PENDING);
 544
 545         if (ltdb_lock_read(module) != 0) {
 546                 return LDB_ERR_OPERATIONS_ERROR;
 547         }
 548
 549         if (ltdb_cache_load(module) != 0) {
 550                 ltdb_unlock_read(module);
 551                 return LDB_ERR_OPERATIONS_ERROR;
 552         }
 553
 554         if (req->op.search.tree == NULL) {
 555                 ltdb_unlock_read(module);
 556                 return LDB_ERR_OPERATIONS_ERROR;
 557         }
 558
 559         if ((req->op.search.base == NULL) || (ldb_dn_is_null(req->op.search.base) == true)) {
 560
 561                 /* Check what we should do with a NULL dn */
 562                 switch (req->op.search.scope) {
 563                 case LDB_SCOPE_BASE:
 564                         ldb_asprintf_errstring(ldb,
 565                                                "NULL Base DN invalid for a base search");
 566                         ret = LDB_ERR_INVALID_DN_SYNTAX;
 567                         break;
 568                 case LDB_SCOPE_ONELEVEL:
 569                         ldb_asprintf_errstring(ldb,
 570                                                "NULL Base DN invalid for a one-level search");
 571                         ret = LDB_ERR_INVALID_DN_SYNTAX;
 572                         break;
 573                 case LDB_SCOPE_SUBTREE:
 574                 default:
 575                         /* We accept subtree searches from a NULL base DN, ie over the whole DB */
 576                         ret = LDB_SUCCESS;
 577                 }
 578         } else if (ldb_dn_is_valid(req->op.search.base) == false) {
 579
 580                 /* We don't want invalid base DNs here */
 581                 ldb_asprintf_errstring(ldb,
 582                                        "Invalid Base DN: %s",
 583                                        ldb_dn_get_linearized(req->op.search.base));
 584                 ret = LDB_ERR_INVALID_DN_SYNTAX;
 585
 586         } else if (ltdb->check_base) {
 587                 /* This database has been marked as 'checkBaseOnSearch', so do a spot check of the base dn */
 588                 ret = ltdb_search_base(module, req->op.search.base);
 589
 590                 if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 591                         ldb_asprintf_errstring(ldb,
 592                                                "No such Base DN: %s",
 593                                                ldb_dn_get_linearized(req->op.search.base));
 594                 }
 595
 596         } else {
 597                 /* If we are not checking the base DN life is easy */
 598                 ret = LDB_SUCCESS;
 599         }
 600
 601         ctx->tree = req->op.search.tree;
 602         ctx->scope = req->op.search.scope;
 603         ctx->base = req->op.search.base;
 604         ctx->attrs = req->op.search.attrs;
 605
 606         if (ret == LDB_SUCCESS) {
 607                 uint32_t match_count = 0;
 608
 609                 ret = ltdb_search_indexed(ctx, &match_count);
 610                 if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 611                         /* Not in the index, therefore OK! */
 612                         ret = LDB_SUCCESS;
 613
 614                 }
 615                 /* Check if we got just a normal error.
 616                  * In that case proceed to a full search unless we got a
 617                  * callback error */
 618                 if ( ! ctx->request_terminated && ret != LDB_SUCCESS) {
 619                         /* Not indexed, so we need to do a full scan */
 620                         if (ltdb->warn_unindexed) {
 621                                 /* useful for debugging when slow performance
 622                                  * is caused by unindexed searches */
 623                                 char *expression = ldb_filter_from_tree(ctx, ctx->tree);
 624                                 ldb_debug(ldb, LDB_DEBUG_ERROR, "ldb FULL SEARCH: %s SCOPE: %s DN: %s",
 625                                                         expression,
 626                                                         req->op.search.scope==LDB_SCOPE_BASE?"base":
 627                                                         req->op.search.scope==LDB_SCOPE_ONELEVEL?"one":
 628                                                         req->op.search.scope==LDB_SCOPE_SUBTREE?"sub":"UNKNOWN",
 629                                                         ldb_dn_get_linearized(req->op.search.base));
 630
 631                                 talloc_free(expression);
 632                         }
 633                         if (match_count != 0) {
 634                                 /* the indexing code gave an error
 635                                  * after having returned at least one
 636                                  * entry. This means the indexes are
 637                                  * corrupt or a database record is
 638                                  * corrupt. We cannot continue with a
 639                                  * full search or we may return
 640                                  * duplicate entries
 641                                  */
 642                                 ltdb_unlock_read(module);
 643                                 return LDB_ERR_OPERATIONS_ERROR;
 644                         }
 645                         ret = ltdb_search_full(ctx);
 646                         if (ret != LDB_SUCCESS) {
 647                                 ldb_set_errstring(ldb, "Indexed and full searches both failed!\n");
 648                         }
 649                 }
 650         }
 651
 652         ltdb_unlock_read(module);
 653
 654         return ret;
 655 }
 656