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