source/lib/ldb/common/ldb.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Andrew Tridgell  2004
   5    Copyright (C) Simo Sorce  2005-2006
   6
   7      ** NOTE! The following LGPL license applies to the ldb
   8      ** library. This does NOT imply that all of Samba is released
   9      ** under the LGPL
  10
  11    This library is free software; you can redistribute it and/or
  12    modify it under the terms of the GNU Lesser General Public
  13    License as published by the Free Software Foundation; either
  14    version 2 of the License, or (at your option) any later version.
  15
  16    This library is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19    Lesser General Public License for more details.
  20
  21    You should have received a copy of the GNU Lesser General Public
  22    License along with this library; if not, write to the Free Software
  23    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24 */
  25
  26 /*
  27  *  Name: ldb
  28  *
  29  *  Component: ldb core API
  30  *
  31  *  Description: core API routines interfacing to ldb backends
  32  *
  33  *  Author: Andrew Tridgell
  34  */
  35
  36 #include "includes.h"
  37 #include "ldb/include/includes.h"
  38
  39 /*
  40    initialise a ldb context
  41    The mem_ctx is optional
  42 */
  43 struct ldb_context *ldb_init(void *mem_ctx)
  44 {
  45         struct ldb_context *ldb = talloc_zero(mem_ctx, struct ldb_context);
  46         int ret;
  47
  48         ret = ldb_setup_wellknown_attributes(ldb);
  49         if (ret != 0) {
  50                 talloc_free(ldb);
  51                 return NULL;
  52         }
  53
  54         ldb_set_utf8_default(ldb);
  55         ldb_set_create_perms(ldb, 0666);
  56
  57         return ldb;
  58 }
  59
  60 static struct ldb_backend {
  61         const char *name;
  62         ldb_connect_fn connect_fn;
  63         struct ldb_backend *prev, *next;
  64 } *ldb_backends = NULL;
  65
  66
  67 static ldb_connect_fn ldb_find_backend(const char *url)
  68 {
  69         struct ldb_backend *backend;
  70
  71         for (backend = ldb_backends; backend; backend = backend->next) {
  72                 if (strncmp(backend->name, url, strlen(backend->name)) == 0) {
  73                         return backend->connect_fn;
  74                 }
  75         }
  76
  77         return NULL;
  78 }
  79
  80 /*
  81  register a new ldb backend
  82 */
  83 int ldb_register_backend(const char *url_prefix, ldb_connect_fn connectfn)
  84 {
  85         struct ldb_backend *backend = talloc(talloc_autofree_context(), struct ldb_backend);
  86
  87         if (ldb_find_backend(url_prefix)) {
  88                 return LDB_SUCCESS;
  89         }
  90
  91         /* Maybe check for duplicity here later on? */
  92
  93         backend->name = talloc_strdup(backend, url_prefix);
  94         backend->connect_fn = connectfn;
  95         DLIST_ADD(ldb_backends, backend);
  96
  97         return LDB_SUCCESS;
  98 }
  99
 100 /*
 101    Return the ldb module form of a database. The URL can either be one of the following forms
 102    ldb://path
 103    ldapi://path
 104
 105    flags is made up of LDB_FLG_*
 106
 107    the options are passed uninterpreted to the backend, and are
 108    backend specific.
 109
 110   This allows modules to get at only the backend module, for example where a module
 111   may wish to direct certain requests at a particular backend.
 112 */
 113 int ldb_connect_backend(struct ldb_context *ldb, const char *url, const char *options[],
 114                         struct ldb_module **backend_module)
 115 {
 116         int ret;
 117         char *backend;
 118         ldb_connect_fn fn;
 119
 120         if (strchr(url, ':') != NULL) {
 121                 backend = talloc_strndup(ldb, url, strchr(url, ':')-url);
 122         } else {
 123                 /* Default to tdb */
 124                 backend = talloc_strdup(ldb, "tdb");
 125         }
 126
 127         fn = ldb_find_backend(backend);
 128
 129         if (fn == NULL) {
 130                 if (ldb_try_load_dso(ldb, backend) == 0) {
 131                         fn = ldb_find_backend(backend);
 132                 }
 133         }
 134
 135         talloc_free(backend);
 136
 137         if (fn == NULL) {
 138                 ldb_debug(ldb, LDB_DEBUG_FATAL, "Unable to find backend for '%s'\n", url);
 139                 return LDB_ERR_OTHER;
 140         }
 141
 142         ret = fn(ldb, url, ldb->flags, options, backend_module);
 143
 144         if (ret != LDB_SUCCESS) {
 145                 ldb_debug(ldb, LDB_DEBUG_ERROR, "Failed to connect to '%s'\n", url);
 146                 return ret;
 147         }
 148         return ret;
 149 }
 150
 151 /*
 152   try to autodetect a basedn if none specified. This fixes one of my
 153   pet hates about ldapsearch, which is that you have to get a long,
 154   complex basedn right to make any use of it.
 155 */
 156 static const struct ldb_dn *ldb_set_default_basedn(struct ldb_context *ldb)
 157 {
 158         TALLOC_CTX *tmp_ctx;
 159         int ret;
 160         static const char *attrs[] = { "defaultNamingContext", NULL };
 161         struct ldb_result *res;
 162         struct ldb_dn *basedn=NULL;
 163
 164         basedn = (struct ldb_dn *)ldb_get_opaque(ldb, "default_baseDN");
 165         if (basedn) {
 166                 return basedn;
 167         }
 168
 169         tmp_ctx = talloc_new(ldb);
 170         ret = ldb_search(ldb, ldb_dn_new(tmp_ctx), LDB_SCOPE_BASE,
 171                          "(objectClass=*)", attrs, &res);
 172         if (ret == LDB_SUCCESS) {
 173                 if (res->count == 1) {
 174                         basedn = ldb_msg_find_attr_as_dn(ldb, res->msgs[0], "defaultNamingContext");
 175                         ldb_set_opaque(ldb, "default_baseDN", basedn);
 176                 }
 177                 talloc_free(res);
 178         }
 179
 180         talloc_free(tmp_ctx);
 181         return basedn;
 182 }
 183
 184 const struct ldb_dn *ldb_get_default_basedn(struct ldb_context *ldb)
 185 {
 186         return (const struct ldb_dn *)ldb_get_opaque(ldb, "default_baseDN");
 187 }
 188
 189 /*
 190  connect to a database. The URL can either be one of the following forms
 191    ldb://path
 192    ldapi://path
 193
 194    flags is made up of LDB_FLG_*
 195
 196    the options are passed uninterpreted to the backend, and are
 197    backend specific
 198 */
 199 int ldb_connect(struct ldb_context *ldb, const char *url, unsigned int flags, const char *options[])
 200 {
 201         int ret;
 202
 203         ldb->flags = flags;
 204
 205         ret = ldb_connect_backend(ldb, url, options, &ldb->modules);
 206         if (ret != LDB_SUCCESS) {
 207                 return ret;
 208         }
 209
 210         if (ldb_load_modules(ldb, options) != LDB_SUCCESS) {
 211                 ldb_debug(ldb, LDB_DEBUG_FATAL, "Unable to load modules for %s: %s\n",
 212                           url, ldb_errstring(ldb));
 213                 return LDB_ERR_OTHER;
 214         }
 215
 216         /* TODO: get timeout from options if available there */
 217         ldb->default_timeout = 300; /* set default to 5 minutes */
 218
 219         /* set the default base dn */
 220         ldb_set_default_basedn(ldb);
 221
 222         return LDB_SUCCESS;
 223 }
 224
 225 void ldb_set_errstring(struct ldb_context *ldb, const char *err_string)
 226 {
 227         if (ldb->err_string) {
 228                 talloc_free(ldb->err_string);
 229         }
 230         ldb->err_string = talloc_strdup(ldb, err_string);
 231 }
 232
 233 void ldb_asprintf_errstring(struct ldb_context *ldb, const char *format, ...)
 234 {
 235         va_list ap;
 236
 237         if (ldb->err_string) {
 238                 talloc_free(ldb->err_string);
 239         }
 240
 241         va_start(ap, format);
 242         ldb->err_string = talloc_vasprintf(ldb, format, ap);
 243         va_end(ap);
 244 }
 245
 246 void ldb_reset_err_string(struct ldb_context *ldb)
 247 {
 248         if (ldb->err_string) {
 249                 talloc_free(ldb->err_string);
 250                 ldb->err_string = NULL;
 251         }
 252 }
 253
 254 #define FIRST_OP(ldb, op) do { \
 255         module = ldb->modules;                                  \
 256         while (module && module->ops->op == NULL) module = module->next; \
 257         if (module == NULL) {                                           \
 258                 ldb_asprintf_errstring(ldb, "unable to find module or backend to handle operation: " #op); \
 259                 return LDB_ERR_OPERATIONS_ERROR;                        \
 260         } \
 261 } while (0)
 262
 263 /*
 264   start a transaction
 265 */
 266 static int ldb_transaction_start_internal(struct ldb_context *ldb)
 267 {
 268         struct ldb_module *module;
 269         int status;
 270         FIRST_OP(ldb, start_transaction);
 271
 272         ldb_reset_err_string(ldb);
 273
 274         status = module->ops->start_transaction(module);
 275         if (status != LDB_SUCCESS) {
 276                 if (ldb->err_string == NULL) {
 277                         /* no error string was setup by the backend */
 278                         ldb_asprintf_errstring(ldb,
 279                                                 "ldb transaction start: %s (%d)",
 280                                                 ldb_strerror(status),
 281                                                 status);
 282                 }
 283         }
 284         return status;
 285 }
 286
 287 /*
 288   commit a transaction
 289 */
 290 static int ldb_transaction_commit_internal(struct ldb_context *ldb)
 291 {
 292         struct ldb_module *module;
 293         int status;
 294         FIRST_OP(ldb, end_transaction);
 295
 296         ldb_reset_err_string(ldb);
 297
 298         status = module->ops->end_transaction(module);
 299         if (status != LDB_SUCCESS) {
 300                 if (ldb->err_string == NULL) {
 301                         /* no error string was setup by the backend */
 302                         ldb_asprintf_errstring(ldb,
 303                                                 "ldb transaction commit: %s (%d)",
 304                                                 ldb_strerror(status),
 305                                                 status);
 306                 }
 307         }
 308         return status;
 309 }
 310
 311 /*
 312   cancel a transaction
 313 */
 314 static int ldb_transaction_cancel_internal(struct ldb_context *ldb)
 315 {
 316         struct ldb_module *module;
 317         int status;
 318         FIRST_OP(ldb, del_transaction);
 319
 320         status = module->ops->del_transaction(module);
 321         if (status != LDB_SUCCESS) {
 322                 if (ldb->err_string == NULL) {
 323                         /* no error string was setup by the backend */
 324                         ldb_asprintf_errstring(ldb,
 325                                                 "ldb transaction cancel: %s (%d)",
 326                                                 ldb_strerror(status),
 327                                                 status);
 328                 }
 329         }
 330         return status;
 331 }
 332
 333 int ldb_transaction_start(struct ldb_context *ldb)
 334 {
 335         /* disable autotransactions */
 336         ldb->transaction_active++;
 337
 338         return ldb_transaction_start_internal(ldb);
 339 }
 340
 341 int ldb_transaction_commit(struct ldb_context *ldb)
 342 {
 343         /* renable autotransactions (when we reach 0) */
 344         if (ldb->transaction_active > 0)
 345                 ldb->transaction_active--;
 346
 347         return ldb_transaction_commit_internal(ldb);
 348 }
 349
 350 int ldb_transaction_cancel(struct ldb_context *ldb)
 351 {
 352         /* renable autotransactions (when we reach 0) */
 353         if (ldb->transaction_active > 0)
 354                 ldb->transaction_active--;
 355
 356         return ldb_transaction_cancel_internal(ldb);
 357 }
 358
 359 static int ldb_autotransaction_start(struct ldb_context *ldb)
 360 {
 361         /* explicit transaction active, ignore autotransaction request */
 362         if (ldb->transaction_active)
 363                 return LDB_SUCCESS;
 364
 365         return ldb_transaction_start_internal(ldb);
 366 }
 367
 368 static int ldb_autotransaction_commit(struct ldb_context *ldb)
 369 {
 370         /* explicit transaction active, ignore autotransaction request */
 371         if (ldb->transaction_active)
 372                 return LDB_SUCCESS;
 373
 374         return ldb_transaction_commit_internal(ldb);
 375 }
 376
 377 static int ldb_autotransaction_cancel(struct ldb_context *ldb)
 378 {
 379         /* explicit transaction active, ignore autotransaction request */
 380         if (ldb->transaction_active)
 381                 return LDB_SUCCESS;
 382
 383         return ldb_transaction_cancel_internal(ldb);
 384 }
 385
 386 /* autostarts a transacion if none active */
 387 static int ldb_autotransaction_request(struct ldb_context *ldb, struct ldb_request *req)
 388 {
 389         int ret;
 390
 391         ret = ldb_autotransaction_start(ldb);
 392         if (ret != LDB_SUCCESS) {
 393                 return ret;
 394         }
 395
 396         ret = ldb_request(ldb, req);
 397         if (ret == LDB_SUCCESS) {
 398                 ret = ldb_wait(req->handle, LDB_WAIT_ALL);
 399         }
 400
 401         if (ret == LDB_SUCCESS) {
 402                 return ldb_autotransaction_commit(ldb);
 403         }
 404         ldb_autotransaction_cancel(ldb);
 405
 406         if (ldb->err_string == NULL) {
 407                 /* no error string was setup by the backend */
 408                 ldb_asprintf_errstring(ldb, "%s (%d)", ldb_strerror(ret), ret);
 409         }
 410
 411         return ret;
 412 }
 413
 414 int ldb_wait(struct ldb_handle *handle, enum ldb_wait_type type)
 415 {
 416         if (!handle) {
 417                 return LDB_SUCCESS;
 418         }
 419
 420         return handle->module->ops->wait(handle, type);
 421 }
 422
 423 /* set the specified timeout or, if timeout is 0 set the default timeout */
 424 /* timeout == -1 means no timeout */
 425 int ldb_set_timeout(struct ldb_context *ldb, struct ldb_request *req, int timeout)
 426 {
 427         if (req == NULL) return LDB_ERR_OPERATIONS_ERROR;
 428
 429         if (timeout != 0) {
 430                 req->timeout = timeout;
 431         } else {
 432                 req->timeout = ldb->default_timeout;
 433         }
 434         req->starttime = time(NULL);
 435
 436         return LDB_SUCCESS;
 437 }
 438
 439 /* calculates the new timeout based on the previous starttime and timeout */
 440 int ldb_set_timeout_from_prev_req(struct ldb_context *ldb, struct ldb_request *oldreq, struct ldb_request *newreq)
 441 {
 442         time_t now;
 443
 444         if (newreq == NULL) return LDB_ERR_OPERATIONS_ERROR;
 445
 446         now = time(NULL);
 447
 448         if (oldreq == NULL)
 449                 return ldb_set_timeout(ldb, newreq, 0);
 450
 451         if ((now - oldreq->starttime) > oldreq->timeout) {
 452                 return LDB_ERR_TIME_LIMIT_EXCEEDED;
 453         }
 454         newreq->starttime = oldreq->starttime;
 455         newreq->timeout = oldreq->timeout - (now - oldreq->starttime);
 456
 457         return LDB_SUCCESS;
 458 }
 459
 460
 461 /*
 462    set the permissions for new files to be passed to open() in
 463    backends that use local files
 464  */
 465 void ldb_set_create_perms(struct ldb_context *ldb, unsigned int perms)
 466 {
 467         ldb->create_perms = perms;
 468 }
 469
 470 /*
 471   start an ldb request
 472   NOTE: the request must be a talloc context.
 473   returns LDB_ERR_* on errors.
 474 */
 475 int ldb_request(struct ldb_context *ldb, struct ldb_request *req)
 476 {
 477         struct ldb_module *module;
 478         int ret;
 479
 480         ldb_reset_err_string(ldb);
 481
 482         /* call the first module in the chain */
 483         switch (req->operation) {
 484         case LDB_SEARCH:
 485                 FIRST_OP(ldb, search);
 486                 ret = module->ops->search(module, req);
 487                 break;
 488         case LDB_ADD:
 489                 FIRST_OP(ldb, add);
 490                 ret = module->ops->add(module, req);
 491                 break;
 492         case LDB_MODIFY:
 493                 FIRST_OP(ldb, modify);
 494                 ret = module->ops->modify(module, req);
 495                 break;
 496         case LDB_DELETE:
 497                 FIRST_OP(ldb, del);
 498                 ret = module->ops->del(module, req);
 499                 break;
 500         case LDB_RENAME:
 501                 FIRST_OP(ldb, rename);
 502                 ret = module->ops->rename(module, req);
 503                 break;
 504         case LDB_SEQUENCE_NUMBER:
 505                 FIRST_OP(ldb, sequence_number);
 506                 ret = module->ops->sequence_number(module, req);
 507                 break;
 508         default:
 509                 FIRST_OP(ldb, request);
 510                 ret = module->ops->request(module, req);
 511                 break;
 512         }
 513
 514         return ret;
 515 }
 516
 517 /*
 518   search the database given a LDAP-like search expression
 519
 520   returns an LDB error code
 521
 522   Use talloc_free to free the ldb_message returned in 'res', if successful
 523
 524 */
 525 int ldb_search_default_callback(struct ldb_context *ldb, void *context, struct ldb_reply *ares)
 526 {
 527         struct ldb_result *res;
 528         int n;
 529
 530         if (!context) {
 531                 ldb_set_errstring(ldb, "NULL Context in callback");
 532                 return LDB_ERR_OPERATIONS_ERROR;
 533         }
 534
 535         res = talloc_get_type(context, struct ldb_result);
 536
 537         if (!res || !ares) {
 538                 ldb_set_errstring(ldb, "NULL res or ares in callback");
 539                 goto error;
 540         }
 541
 542         switch (ares->type) {
 543         case LDB_REPLY_ENTRY:
 544                 res->msgs = talloc_realloc(res, res->msgs, struct ldb_message *, res->count + 2);
 545                 if (! res->msgs) {
 546                         goto error;
 547                 }
 548
 549                 res->msgs[res->count + 1] = NULL;
 550
 551                 res->msgs[res->count] = talloc_move(res->msgs, &ares->message);
 552                 res->count++;
 553                 break;
 554         case LDB_REPLY_REFERRAL:
 555                 if (res->refs) {
 556                         for (n = 0; res->refs[n]; n++) /*noop*/ ;
 557                 } else {
 558                         n = 0;
 559                 }
 560
 561                 res->refs = talloc_realloc(res, res->refs, char *, n + 2);
 562                 if (! res->refs) {
 563                         goto error;
 564                 }
 565
 566                 res->refs[n] = talloc_move(res->refs, &ares->referral);
 567                 res->refs[n + 1] = NULL;
 568         case LDB_REPLY_EXTENDED:
 569         case LDB_REPLY_DONE:
 570                 /* TODO: we should really support controls on entries and referrals too! */
 571                 res->controls = talloc_move(res, &ares->controls);
 572                 break;
 573         }
 574         talloc_free(ares);
 575         return LDB_SUCCESS;
 576
 577 error:
 578         talloc_free(ares);
 579         return LDB_ERR_OPERATIONS_ERROR;
 580 }
 581
 582 int ldb_build_search_req(struct ldb_request **ret_req,
 583                         struct ldb_context *ldb,
 584                         void *mem_ctx,
 585                         const struct ldb_dn *base,
 586                         enum ldb_scope scope,
 587                         const char *expression,
 588                         const char * const *attrs,
 589                         struct ldb_control **controls,
 590                         void *context,
 591                         ldb_request_callback_t callback)
 592 {
 593         struct ldb_request *req;
 594
 595         *ret_req = NULL;
 596
 597         req = talloc(mem_ctx, struct ldb_request);
 598         if (req == NULL) {
 599                 ldb_set_errstring(ldb, "Out of Memory");
 600                 return LDB_ERR_OPERATIONS_ERROR;
 601         }
 602
 603         req->operation = LDB_SEARCH;
 604         if (base == NULL) {
 605                 req->op.search.base = ldb_dn_new(req);
 606         } else {
 607                 req->op.search.base = base;
 608         }
 609         req->op.search.scope = scope;
 610
 611         req->op.search.tree = ldb_parse_tree(req, expression);
 612         if (req->op.search.tree == NULL) {
 613                 ldb_set_errstring(ldb, "Unable to parse search expression");
 614                 talloc_free(req);
 615                 return LDB_ERR_OPERATIONS_ERROR;
 616         }
 617
 618         req->op.search.attrs = attrs;
 619         req->controls = controls;
 620         req->context = context;
 621         req->callback = callback;
 622
 623         *ret_req = req;
 624         return LDB_SUCCESS;
 625 }
 626
 627 int ldb_build_add_req(struct ldb_request **ret_req,
 628                         struct ldb_context *ldb,
 629                         void *mem_ctx,
 630                         const struct ldb_message *message,
 631                         struct ldb_control **controls,
 632                         void *context,
 633                         ldb_request_callback_t callback)
 634 {
 635         struct ldb_request *req;
 636
 637         *ret_req = NULL;
 638
 639         req = talloc(mem_ctx, struct ldb_request);
 640         if (req == NULL) {
 641                 ldb_set_errstring(ldb, "Out of Memory");
 642                 return LDB_ERR_OPERATIONS_ERROR;
 643         }
 644
 645         req->operation = LDB_ADD;
 646         req->op.add.message = message;
 647         req->controls = controls;
 648         req->context = context;
 649         req->callback = callback;
 650
 651         *ret_req = req;
 652
 653         return LDB_SUCCESS;
 654 }
 655
 656 int ldb_build_mod_req(struct ldb_request **ret_req,
 657                         struct ldb_context *ldb,
 658                         void *mem_ctx,
 659                         const struct ldb_message *message,
 660                         struct ldb_control **controls,
 661                         void *context,
 662                         ldb_request_callback_t callback)
 663 {
 664         struct ldb_request *req;
 665
 666         *ret_req = NULL;
 667
 668         req = talloc(mem_ctx, struct ldb_request);
 669         if (req == NULL) {
 670                 ldb_set_errstring(ldb, "Out of Memory");
 671                 return LDB_ERR_OPERATIONS_ERROR;
 672         }
 673
 674         req->operation = LDB_MODIFY;
 675         req->op.mod.message = message;
 676         req->controls = controls;
 677         req->context = context;
 678         req->callback = callback;
 679
 680         *ret_req = req;
 681
 682         return LDB_SUCCESS;
 683 }
 684
 685 int ldb_build_del_req(struct ldb_request **ret_req,
 686                         struct ldb_context *ldb,
 687                         void *mem_ctx,
 688                         const struct ldb_dn *dn,
 689                         struct ldb_control **controls,
 690                         void *context,
 691                         ldb_request_callback_t callback)
 692 {
 693         struct ldb_request *req;
 694
 695         *ret_req = NULL;
 696
 697         req = talloc(mem_ctx, struct ldb_request);
 698         if (req == NULL) {
 699                 ldb_set_errstring(ldb, "Out of Memory");
 700                 return LDB_ERR_OPERATIONS_ERROR;
 701         }
 702
 703         req->operation = LDB_DELETE;
 704         req->op.del.dn = dn;
 705         req->controls = controls;
 706         req->context = context;
 707         req->callback = callback;
 708
 709         *ret_req = req;
 710
 711         return LDB_SUCCESS;
 712 }
 713
 714 int ldb_build_rename_req(struct ldb_request **ret_req,
 715                         struct ldb_context *ldb,
 716                         void *mem_ctx,
 717                         const struct ldb_dn *olddn,
 718                         const struct ldb_dn *newdn,
 719                         struct ldb_control **controls,
 720                         void *context,
 721                         ldb_request_callback_t callback)
 722 {
 723         struct ldb_request *req;
 724
 725         *ret_req = NULL;
 726
 727         req = talloc(mem_ctx, struct ldb_request);
 728         if (req == NULL) {
 729                 ldb_set_errstring(ldb, "Out of Memory");
 730                 return LDB_ERR_OPERATIONS_ERROR;
 731         }
 732
 733         req->operation = LDB_RENAME;
 734         req->op.rename.olddn = olddn;
 735         req->op.rename.newdn = newdn;
 736         req->controls = controls;
 737         req->context = context;
 738         req->callback = callback;
 739
 740         *ret_req = req;
 741
 742         return LDB_SUCCESS;
 743 }
 744
 745 /*
 746   note that ldb_search() will automatically replace a NULL 'base' value with the
 747   defaultNamingContext from the rootDSE if available.
 748 */
 749 int ldb_search(struct ldb_context *ldb,
 750                const struct ldb_dn *base,
 751                enum ldb_scope scope,
 752                const char *expression,
 753                const char * const *attrs,
 754                struct ldb_result **_res)
 755 {
 756         struct ldb_request *req;
 757         int ret;
 758         struct ldb_result *res;
 759
 760         *_res = NULL;
 761
 762         res = talloc_zero(ldb, struct ldb_result);
 763         if (!res) {
 764                 return LDB_ERR_OPERATIONS_ERROR;
 765         }
 766
 767         ret = ldb_build_search_req(&req, ldb, ldb,
 768                                         base?base:ldb_get_default_basedn(ldb),
 769                                         scope,
 770                                         expression,
 771                                         attrs,
 772                                         NULL,
 773                                         res,
 774                                         ldb_search_default_callback);
 775
 776         if (ret != LDB_SUCCESS) goto done;
 777
 778         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 779
 780         ret = ldb_request(ldb, req);
 781
 782         if (ret == LDB_SUCCESS) {
 783                 ret = ldb_wait(req->handle, LDB_WAIT_ALL);
 784         }
 785
 786         talloc_free(req);
 787
 788 done:
 789         if (ret != LDB_SUCCESS) {
 790                 talloc_free(res);
 791         }
 792
 793         *_res = res;
 794         return ret;
 795 }
 796
 797 /*
 798  a useful search function where you can easily define the expression and that
 799  takes a memory context where results are allocated
 800 */
 801
 802 int ldb_search_exp_fmt(struct ldb_context *ldb, TALLOC_CTX *mem_ctx, struct ldb_result **result,
 803                         struct ldb_dn *base, enum ldb_scope scope, const char * const *attrs,
 804                         const char *exp_fmt, ...)
 805 {
 806         struct ldb_result *res;
 807         char *expression;
 808         va_list ap;
 809         int ret;
 810
 811         res = NULL;
 812         *result = NULL;
 813
 814         va_start(ap, exp_fmt);
 815         expression = talloc_vasprintf(mem_ctx, exp_fmt, ap);
 816         va_end(ap);
 817
 818         if ( ! expression) {
 819                 return LDB_ERR_OPERATIONS_ERROR;
 820         }
 821
 822         ret = ldb_search(ldb, base, scope, expression, attrs, &res);
 823
 824         if (ret == LDB_SUCCESS) {
 825                 talloc_steal(mem_ctx, res);
 826                 *result = res;
 827         } else {
 828                 talloc_free(res);
 829         }
 830
 831         talloc_free(expression);
 832
 833         return ret;
 834 }
 835
 836 /*
 837   add a record to the database. Will fail if a record with the given class and key
 838   already exists
 839 */
 840 int ldb_add(struct ldb_context *ldb,
 841             const struct ldb_message *message)
 842 {
 843         struct ldb_request *req;
 844         int ret;
 845
 846         ret = ldb_msg_sanity_check(ldb, message);
 847         if (ret != LDB_SUCCESS) {
 848                 return ret;
 849         }
 850
 851         ret = ldb_build_add_req(&req, ldb, ldb,
 852                                         message,
 853                                         NULL,
 854                                         NULL,
 855                                         NULL);
 856
 857         if (ret != LDB_SUCCESS) return ret;
 858
 859         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 860
 861         /* do request and autostart a transaction */
 862         ret = ldb_autotransaction_request(ldb, req);
 863
 864         talloc_free(req);
 865         return ret;
 866 }
 867
 868 /*
 869   modify the specified attributes of a record
 870 */
 871 int ldb_modify(struct ldb_context *ldb,
 872                const struct ldb_message *message)
 873 {
 874         struct ldb_request *req;
 875         int ret;
 876
 877         ret = ldb_msg_sanity_check(ldb, message);
 878         if (ret != LDB_SUCCESS) {
 879                 return ret;
 880         }
 881
 882         ret = ldb_build_mod_req(&req, ldb, ldb,
 883                                         message,
 884                                         NULL,
 885                                         NULL,
 886                                         NULL);
 887
 888         if (ret != LDB_SUCCESS) return ret;
 889
 890         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 891
 892         /* do request and autostart a transaction */
 893         ret = ldb_autotransaction_request(ldb, req);
 894
 895         talloc_free(req);
 896         return ret;
 897 }
 898
 899
 900 /*
 901   delete a record from the database
 902 */
 903 int ldb_delete(struct ldb_context *ldb, const struct ldb_dn *dn)
 904 {
 905         struct ldb_request *req;
 906         int ret;
 907
 908         ret = ldb_build_del_req(&req, ldb, ldb,
 909                                         dn,
 910                                         NULL,
 911                                         NULL,
 912                                         NULL);
 913
 914         if (ret != LDB_SUCCESS) return ret;
 915
 916         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 917
 918         /* do request and autostart a transaction */
 919         ret = ldb_autotransaction_request(ldb, req);
 920
 921         talloc_free(req);
 922         return ret;
 923 }
 924
 925 /*
 926   rename a record in the database
 927 */
 928 int ldb_rename(struct ldb_context *ldb, const struct ldb_dn *olddn, const struct ldb_dn *newdn)
 929 {
 930         struct ldb_request *req;
 931         int ret;
 932
 933         ret = ldb_build_rename_req(&req, ldb, ldb,
 934                                         olddn,
 935                                         newdn,
 936                                         NULL,
 937                                         NULL,
 938                                         NULL);
 939
 940         if (ret != LDB_SUCCESS) return ret;
 941
 942         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 943
 944         /* do request and autostart a transaction */
 945         ret = ldb_autotransaction_request(ldb, req);
 946
 947         talloc_free(req);
 948         return ret;
 949 }
 950
 951
 952 /*
 953   return the global sequence number
 954 */
 955 int ldb_sequence_number(struct ldb_context *ldb, enum ldb_sequence_type type, uint64_t *seq_num)
 956 {
 957         struct ldb_request *req;
 958         int ret;
 959
 960         req = talloc(ldb, struct ldb_request);
 961         if (req == NULL) {
 962                 ldb_set_errstring(ldb, "Out of Memory");
 963                 return LDB_ERR_OPERATIONS_ERROR;
 964         }
 965
 966         req->operation = LDB_SEQUENCE_NUMBER;
 967         req->controls = NULL;
 968         req->context = NULL;
 969         req->callback = NULL;
 970         ldb_set_timeout(ldb, req, 0); /* use default timeout */
 971
 972         req->op.seq_num.type = type;
 973         /* do request and autostart a transaction */
 974         ret = ldb_request(ldb, req);
 975
 976         if (ret == LDB_SUCCESS) {
 977                 *seq_num = req->op.seq_num.seq_num;
 978         }
 979
 980         talloc_free(req);
 981         return ret;
 982 }
 983
 984
 985
 986 /*
 987   return extended error information
 988 */
 989 const char *ldb_errstring(struct ldb_context *ldb)
 990 {
 991         if (ldb->err_string) {
 992                 return ldb->err_string;
 993         }
 994
 995         return NULL;
 996 }
 997
 998 /*
 999   return a string explaining what a ldb error constant meancs
1000 */
1001 const char *ldb_strerror(int ldb_err)
1002 {
1003         switch (ldb_err) {
1004         case LDB_SUCCESS:
1005                 return "Success";
1006         case LDB_ERR_OPERATIONS_ERROR:
1007                 return "Operations error";
1008         case LDB_ERR_PROTOCOL_ERROR:
1009                 return "Protocol error";
1010         case LDB_ERR_TIME_LIMIT_EXCEEDED:
1011                 return "Time limit exceeded";
1012         case LDB_ERR_SIZE_LIMIT_EXCEEDED:
1013                 return "Size limit exceeded";
1014         case LDB_ERR_COMPARE_FALSE:
1015                 return "Compare false";
1016         case LDB_ERR_COMPARE_TRUE:
1017                 return "Compare true";
1018         case LDB_ERR_AUTH_METHOD_NOT_SUPPORTED:
1019                 return "Auth method not supported";
1020         case LDB_ERR_STRONG_AUTH_REQUIRED:
1021                 return "Strong auth required";
1022 /* 9 RESERVED */
1023         case LDB_ERR_REFERRAL:
1024                 return "Referral error";
1025         case LDB_ERR_ADMIN_LIMIT_EXCEEDED:
1026                 return "Admin limit exceeded";
1027         case LDB_ERR_UNSUPPORTED_CRITICAL_EXTENSION:
1028                 return "Unsupported critical extension";
1029         case LDB_ERR_CONFIDENTIALITY_REQUIRED:
1030                 return "Confidentiality required";
1031         case LDB_ERR_SASL_BIND_IN_PROGRESS:
1032                 return "SASL bind in progress";
1033         case LDB_ERR_NO_SUCH_ATTRIBUTE:
1034                 return "No such attribute";
1035         case LDB_ERR_UNDEFINED_ATTRIBUTE_TYPE:
1036                 return "Undefined attribute type";
1037         case LDB_ERR_INAPPROPRIATE_MATCHING:
1038                 return "Inappropriate matching";
1039         case LDB_ERR_CONSTRAINT_VIOLATION:
1040                 return "Constraint violation";
1041         case LDB_ERR_ATTRIBUTE_OR_VALUE_EXISTS:
1042                 return "Attribute or value exists";
1043         case LDB_ERR_INVALID_ATTRIBUTE_SYNTAX:
1044                 return "Invalid attribute syntax";
1045 /* 22-31 unused */
1046         case LDB_ERR_NO_SUCH_OBJECT:
1047                 return "No such object";
1048         case LDB_ERR_ALIAS_PROBLEM:
1049                 return "Alias problem";
1050         case LDB_ERR_INVALID_DN_SYNTAX:
1051                 return "Invalid DN syntax";
1052 /* 35 RESERVED */
1053         case LDB_ERR_ALIAS_DEREFERENCING_PROBLEM:
1054                 return "Alias dereferencing problem";
1055 /* 37-47 unused */
1056         case LDB_ERR_INAPPROPRIATE_AUTHENTICATION:
1057                 return "Inappropriate authentication";
1058         case LDB_ERR_INVALID_CREDENTIALS:
1059                 return "Invalid credentials";
1060         case LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS:
1061                 return "insufficient access rights";
1062         case LDB_ERR_BUSY:
1063                 return "Busy";
1064         case LDB_ERR_UNAVAILABLE:
1065                 return "Unavailable";
1066         case LDB_ERR_UNWILLING_TO_PERFORM:
1067                 return "Unwilling to perform";
1068         case LDB_ERR_LOOP_DETECT:
1069                 return "Loop detect";
1070 /* 55-63 unused */
1071         case LDB_ERR_NAMING_VIOLATION:
1072                 return "Naming violation";
1073         case LDB_ERR_OBJECT_CLASS_VIOLATION:
1074                 return "Object class violation";
1075         case LDB_ERR_NOT_ALLOWED_ON_NON_LEAF:
1076                 return "Not allowed on non-leaf";
1077         case LDB_ERR_NOT_ALLOWED_ON_RDN:
1078                 return "Not allowed on RDN";
1079         case LDB_ERR_ENTRY_ALREADY_EXISTS:
1080                 return "Entry already exists";
1081         case LDB_ERR_OBJECT_CLASS_MODS_PROHIBITED:
1082                 return "Object class mods prohibited";
1083 /* 70 RESERVED FOR CLDAP */
1084         case LDB_ERR_AFFECTS_MULTIPLE_DSAS:
1085                 return "Affects multiple DSAs";
1086 /* 72-79 unused */
1087         case LDB_ERR_OTHER:
1088                 return "Other";
1089         }
1090
1091         return "Unknown error";
1092 }
1093
1094 /*
1095   set backend specific opaque parameters
1096 */
1097 int ldb_set_opaque(struct ldb_context *ldb, const char *name, void *value)
1098 {
1099         struct ldb_opaque *o;
1100
1101         /* allow updating an existing value */
1102         for (o=ldb->opaque;o;o=o->next) {
1103                 if (strcmp(o->name, name) == 0) {
1104                         o->value = value;
1105                         return LDB_SUCCESS;
1106                 }
1107         }
1108
1109         o = talloc(ldb, struct ldb_opaque);
1110         if (o == NULL) {
1111                 ldb_oom(ldb);
1112                 return LDB_ERR_OTHER;
1113         }
1114         o->next = ldb->opaque;
1115         o->name = name;
1116         o->value = value;
1117         ldb->opaque = o;
1118         return LDB_SUCCESS;
1119 }
1120
1121 /*
1122   get a previously set opaque value
1123 */
1124 void *ldb_get_opaque(struct ldb_context *ldb, const char *name)
1125 {
1126         struct ldb_opaque *o;
1127         for (o=ldb->opaque;o;o=o->next) {
1128                 if (strcmp(o->name, name) == 0) {
1129                         return o->value;
1130                 }
1131         }
1132         return NULL;
1133 }