source4/dsdb/samdb/ldb_modules/samba_dsdb.c

   1 /*
   2    Samba4 module loading module
   3
   4    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 /*
  21  *  Name: ldb
  22  *
  23  *  Component: Samba4 module loading module
  24  *
  25  *  Description: Implement a single 'module' in the ldb database,
  26  *  which loads the remaining modules based on 'choice of configuration' attributes
  27  *
  28  *  This is to avoid forcing a reprovision of the ldb databases when we change the internal structure of the code
  29  *
  30  *  Author: Andrew Bartlett
  31  */
  32
  33 #include "includes.h"
  34 #include <ldb.h>
  35 #include <ldb_errors.h>
  36 #include <ldb_module.h>
  37 #include "dsdb/samdb/ldb_modules/util.h"
  38 #include "dsdb/samdb/samdb.h"
  39 #include "librpc/ndr/libndr.h"
  40 #include "auth/credentials/credentials.h"
  41 #include "param/secrets.h"
  42 #include "lib/ldb-samba/ldb_wrap.h"
  43
  44 static int read_at_rootdse_record(struct ldb_context *ldb, struct ldb_module *module, TALLOC_CTX *mem_ctx,
  45                                   struct ldb_message **msg, struct ldb_request *parent)
  46 {
  47         int ret;
  48         static const char *rootdse_attrs[] = { "defaultNamingContext", "configurationNamingContext", "schemaNamingContext", NULL };
  49         struct ldb_result *rootdse_res;
  50         struct ldb_dn *rootdse_dn;
  51         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  52         if (!tmp_ctx) {
  53                 return ldb_oom(ldb);
  54         }
  55
  56         rootdse_dn = ldb_dn_new(tmp_ctx, ldb, "@ROOTDSE");
  57         if (!rootdse_dn) {
  58                 talloc_free(tmp_ctx);
  59                 return ldb_oom(ldb);
  60         }
  61
  62         ret = dsdb_module_search_dn(module, tmp_ctx, &rootdse_res, rootdse_dn,
  63                                     rootdse_attrs, DSDB_FLAG_NEXT_MODULE, parent);
  64         if (ret != LDB_SUCCESS) {
  65                 talloc_free(tmp_ctx);
  66                 return ret;
  67         }
  68
  69         talloc_steal(mem_ctx, rootdse_res->msgs);
  70         *msg = rootdse_res->msgs[0];
  71
  72         talloc_free(tmp_ctx);
  73
  74         return ret;
  75 }
  76
  77 static int prepare_modules_line(struct ldb_context *ldb,
  78                                 TALLOC_CTX *mem_ctx,
  79                                 const struct ldb_message *rootdse_msg,
  80                                 struct ldb_message *msg, const char *backend_attr,
  81                                 const char *backend_mod, const char **backend_mod_list)
  82 {
  83         int ret;
  84         const char **backend_full_list;
  85         const char *backend_dn;
  86         char *mod_list_string;
  87         char *full_string;
  88         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  89         if (!tmp_ctx) {
  90                 return ldb_oom(ldb);
  91         }
  92
  93         if (backend_attr) {
  94                 backend_dn = ldb_msg_find_attr_as_string(rootdse_msg, backend_attr, NULL);
  95                 if (!backend_dn) {
  96                         ldb_asprintf_errstring(ldb,
  97                                                "samba_dsdb_init: "
  98                                                "unable to read %s from %s:%s",
  99                                                backend_attr, ldb_dn_get_linearized(rootdse_msg->dn),
 100                                                ldb_errstring(ldb));
 101                         return LDB_ERR_CONSTRAINT_VIOLATION;
 102                 }
 103         } else {
 104                 backend_dn = "*";
 105         }
 106
 107         if (backend_mod) {
 108                 char **b = str_list_make_single(tmp_ctx, backend_mod);
 109                 backend_full_list = discard_const_p(const char *, b);
 110         } else {
 111                 char **b = str_list_make_empty(tmp_ctx);
 112                 backend_full_list = discard_const_p(const char *, b);
 113         }
 114         if (!backend_full_list) {
 115                 talloc_free(tmp_ctx);
 116                 return ldb_oom(ldb);
 117         }
 118
 119         backend_full_list = str_list_append_const(backend_full_list, backend_mod_list);
 120         if (!backend_full_list) {
 121                 talloc_free(tmp_ctx);
 122                 return ldb_oom(ldb);
 123         }
 124
 125         mod_list_string = str_list_join(tmp_ctx, backend_full_list, ',');
 126         if (!mod_list_string) {
 127                 talloc_free(tmp_ctx);
 128                 return ldb_oom(ldb);
 129         }
 130
 131         full_string = talloc_asprintf(tmp_ctx, "%s:%s", backend_dn, mod_list_string);
 132         ret = ldb_msg_add_steal_string(msg, "modules", full_string);
 133         talloc_free(tmp_ctx);
 134         return ret;
 135 }
 136
 137 /*
 138  * Force overwrite of the credentials with those
 139  * specified in secrets.ldb, to connect across the
 140  * ldapi socket to an LDAP backend
 141  */
 142
 143 static int set_ldap_credentials(struct ldb_context *ldb, bool use_external)
 144 {
 145         const char *secrets_ldb_path, *sam_ldb_path;
 146         char *private_dir, *p, *error_string;
 147         struct ldb_context *secrets_ldb;
 148         struct cli_credentials *cred;
 149         struct loadparm_context *lp_ctx = ldb_get_opaque(ldb, "loadparm");
 150         TALLOC_CTX *tmp_ctx = talloc_new(ldb);
 151
 152         if (!tmp_ctx) {
 153                 return ldb_oom(ldb);
 154         }
 155
 156         cred = cli_credentials_init(ldb);
 157         if (!cred) {
 158                 talloc_free(tmp_ctx);
 159                 return ldb_oom(ldb);
 160         }
 161         cli_credentials_set_anonymous(cred);
 162         if (use_external) {
 163                 cli_credentials_set_forced_sasl_mech(cred, "EXTERNAL");
 164         } else {
 165                 cli_credentials_set_forced_sasl_mech(cred, "DIGEST-MD5");
 166
 167                 /*
 168                  * We don't want to use krb5 to talk to our samdb - recursion
 169                  * here would be bad, and this account isn't in the KDC
 170                  * anyway
 171                  */
 172                 cli_credentials_set_kerberos_state(cred, CRED_DONT_USE_KERBEROS);
 173
 174                 /*
 175                  * Work out where *our* secrets.ldb is.  It must be in
 176                  * the same directory as sam.ldb
 177                  */
 178                 sam_ldb_path = (const char *)ldb_get_opaque(ldb, "ldb_url");
 179                 if (!sam_ldb_path) {
 180                         talloc_free(tmp_ctx);
 181                         return ldb_operr(ldb);
 182                 }
 183                 if (strncmp("tdb://", sam_ldb_path, 6) == 0) {
 184                         sam_ldb_path += 6;
 185                 }
 186                 private_dir = talloc_strdup(tmp_ctx, sam_ldb_path);
 187                 p = strrchr(private_dir, '/');
 188                 if (p) {
 189                         *p = '\0';
 190                 } else {
 191                         private_dir = talloc_strdup(tmp_ctx, ".");
 192                 }
 193
 194                 secrets_ldb_path = talloc_asprintf(private_dir, "tdb://%s/secrets.ldb",
 195                                                    private_dir);
 196
 197                 if (!secrets_ldb_path) {
 198                         talloc_free(tmp_ctx);
 199                         return ldb_oom(ldb);
 200                 }
 201
 202                 /*
 203                  * Now that we have found the location, connect to
 204                  * secrets.ldb so we can read the SamDB Credentials
 205                  * record
 206                  */
 207                 secrets_ldb = ldb_wrap_connect(tmp_ctx, NULL, lp_ctx, secrets_ldb_path,
 208                                                NULL, NULL, 0);
 209
 210                 if (!NT_STATUS_IS_OK(cli_credentials_set_secrets(cred, NULL, secrets_ldb, NULL,
 211                                                                  SECRETS_LDAP_FILTER, &error_string))) {
 212                         ldb_asprintf_errstring(ldb, "Failed to read LDAP backend password from %s", secrets_ldb_path);
 213                         talloc_free(tmp_ctx);
 214                         return LDB_ERR_STRONG_AUTH_REQUIRED;
 215                 }
 216         }
 217
 218         /*
 219          * Finally overwrite any supplied credentials with
 220          * these ones, as only secrets.ldb contains the magic
 221          * credentials to talk on the ldapi socket
 222          */
 223         if (ldb_set_opaque(ldb, "credentials", cred)) {
 224                 talloc_free(tmp_ctx);
 225                 return ldb_operr(ldb);
 226         }
 227         talloc_free(tmp_ctx);
 228         return LDB_SUCCESS;
 229 }
 230
 231 static int samba_dsdb_init(struct ldb_module *module)
 232 {
 233         struct ldb_context *ldb = ldb_module_get_ctx(module);
 234         int ret, len, i, j;
 235         TALLOC_CTX *tmp_ctx = talloc_new(module);
 236         struct ldb_result *res;
 237         struct ldb_message *rootdse_msg = NULL, *partition_msg;
 238         struct ldb_dn *samba_dsdb_dn, *partition_dn, *indexlist_dn;
 239         struct ldb_module *backend_module, *module_chain;
 240         const char **final_module_list, **reverse_module_list;
 241         /*
 242           Add modules to the list to activate them by default
 243           beware often order is important
 244
 245           Some Known ordering constraints:
 246           - rootdse must be first, as it makes redirects from "" -> cn=rootdse
 247           - extended_dn_in must be before objectclass.c, as it resolves the DN
 248           - objectclass must be before password_hash and samldb since these LDB
 249             modules require the expanded "objectClass" list
 250           - objectclass must be before descriptor and acl, as both assume that
 251             objectClass values are sorted
 252           - objectclass_attrs must be behind operational in order to see all
 253             attributes (the operational module protects and therefore
 254             suppresses per default some important ones)
 255           - partition must be last
 256           - each partition has its own module list then
 257
 258           The list is presented here as a set of declarations to show the
 259           stack visually - the code below then handles the creation of the list
 260           based on the parameters loaded from the database.
 261         */
 262         static const char *modules_list1[] = {"resolve_oids",
 263                                              "rootdse",
 264                                              "dsdb_notification",
 265                                              "schema_load",
 266                                              "lazy_commit",
 267                                              "dirsync",
 268                                              "paged_results",
 269                                              "vlv",
 270                                              "ranged_results",
 271                                              "anr",
 272                                              "server_sort",
 273                                              "asq",
 274                                              "extended_dn_store",
 275                                              NULL };
 276         /* extended_dn_in or extended_dn_in_openldap goes here */
 277         static const char *modules_list1a[] = {"objectclass",
 278                                              "tombstone_reanimate",
 279                                              "descriptor",
 280                                              "acl",
 281                                              "aclread",
 282                                              "samldb",
 283                                              "password_hash",
 284                                              "instancetype",
 285                                              "objectclass_attrs",
 286                                              NULL };
 287
 288         const char **link_modules;
 289         static const char *fedora_ds_modules[] = {
 290                 "rdn_name", NULL };
 291         static const char *openldap_modules[] = {
 292                 NULL };
 293         static const char *tdb_modules_list[] = {
 294                 "rdn_name",
 295                 "subtree_delete",
 296                 "repl_meta_data",
 297                 "operational",
 298                 "subtree_rename",
 299                 "linked_attributes",
 300                 NULL};
 301
 302         const char *extended_dn_module;
 303         const char *extended_dn_module_ldb = "extended_dn_out_ldb";
 304         const char *extended_dn_module_fds = "extended_dn_out_fds";
 305         const char *extended_dn_module_openldap = "extended_dn_out_openldap";
 306         const char *extended_dn_in_module = "extended_dn_in";
 307
 308         static const char *modules_list2[] = {"dns_notify",
 309                                               "show_deleted",
 310                                               "new_partition",
 311                                               "partition",
 312                                               NULL };
 313
 314         const char **backend_modules;
 315         static const char *fedora_ds_backend_modules[] = {
 316                 "dsdb_flags_ignore", "nsuniqueid", "paged_searches", "simple_dn", NULL };
 317         static const char *openldap_backend_modules[] = {
 318                 "dsdb_flags_ignore", "entryuuid", "simple_dn", NULL };
 319
 320         static const char *samba_dsdb_attrs[] = { "backendType",
 321                                                   SAMBA_COMPATIBLE_FEATURES_ATTR,
 322                                                   SAMBA_REQUIRED_FEATURES_ATTR, NULL };
 323         static const char *indexlist_attrs[] = { SAMBA_FEATURES_SUPPORTED_FLAG, NULL };
 324         static const char *partition_attrs[] = { "ldapBackend", NULL };
 325         const char *backendType, *backendUrl;
 326         bool use_sasl_external = false;
 327
 328         const char *current_supportedFeatures[] = {};
 329
 330         if (!tmp_ctx) {
 331                 return ldb_oom(ldb);
 332         }
 333
 334         ret = ldb_register_samba_handlers(ldb);
 335         if (ret != LDB_SUCCESS) {
 336                 talloc_free(tmp_ctx);
 337                 return ret;
 338         }
 339
 340         samba_dsdb_dn = ldb_dn_new(tmp_ctx, ldb, "@SAMBA_DSDB");
 341         if (!samba_dsdb_dn) {
 342                 talloc_free(tmp_ctx);
 343                 return ldb_oom(ldb);
 344         }
 345
 346         indexlist_dn = ldb_dn_new(tmp_ctx, ldb, "@INDEXLIST");
 347         if (!samba_dsdb_dn) {
 348                 talloc_free(tmp_ctx);
 349                 return ldb_oom(ldb);
 350         }
 351
 352         partition_dn = ldb_dn_new(tmp_ctx, ldb, DSDB_PARTITION_DN);
 353         if (!partition_dn) {
 354                 talloc_free(tmp_ctx);
 355                 return ldb_oom(ldb);
 356         }
 357
 358 #define CHECK_LDB_RET(check_ret)                                \
 359         do {                                                    \
 360                 if (check_ret != LDB_SUCCESS) {                 \
 361                         talloc_free(tmp_ctx);                   \
 362                         return check_ret;                       \
 363                 }                                               \
 364         } while (0)
 365
 366         ret = dsdb_module_search_dn(module, tmp_ctx, &res, samba_dsdb_dn,
 367                                     samba_dsdb_attrs, DSDB_FLAG_NEXT_MODULE, NULL);
 368         if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 369                 backendType = "ldb";
 370         } else if (ret == LDB_SUCCESS) {
 371                 struct ldb_message_element *requiredFeatures;
 372                 struct ldb_message_element *old_compatibleFeatures;
 373
 374                 backendType = ldb_msg_find_attr_as_string(res->msgs[0], "backendType", "ldb");
 375
 376                 requiredFeatures = ldb_msg_find_element(res->msgs[0], SAMBA_REQUIRED_FEATURES_ATTR);
 377                 if (requiredFeatures != NULL) {
 378                         ldb_set_errstring(ldb, "This Samba database was created with "
 379                                           "a newer Samba version and is marked with "
 380                                           "requiredFeatures in @SAMBA_DSDB.  "
 381                                           "This database can not safely be read by this Samba version");
 382                         return LDB_ERR_OPERATIONS_ERROR;
 383                 }
 384
 385                 old_compatibleFeatures = ldb_msg_find_element(res->msgs[0],
 386                                                               SAMBA_COMPATIBLE_FEATURES_ATTR);
 387
 388                 if (old_compatibleFeatures) {
 389                         struct ldb_message *features_msg;
 390                         struct ldb_message_element *features_el;
 391                         int samba_options_supported = 0;
 392                         ret = dsdb_module_search_dn(module, tmp_ctx, &res,
 393                                                     indexlist_dn,
 394                                                     indexlist_attrs,
 395                                                     DSDB_FLAG_NEXT_MODULE, NULL);
 396                         if (ret == LDB_SUCCESS) {
 397                                 samba_options_supported
 398                                         = ldb_msg_find_attr_as_int(res->msgs[0],
 399                                                                    SAMBA_FEATURES_SUPPORTED_FLAG,
 400                                                                    0);
 401
 402                         } else if (ret == LDB_ERR_NO_SUCH_OBJECT) {
 403                                 /*
 404                                  * If we don't have @INDEXLIST yet, then we
 405                                  * are so early in set-up that we know this is
 406                                  * a blank DB, so no need to wripe out old
 407                                  * features
 408                                  */
 409                                 samba_options_supported = 1;
 410                         }
 411
 412                         features_msg = ldb_msg_new(res);
 413                         if (features_msg == NULL) {
 414                                 return ldb_module_operr(module);
 415                         }
 416                         features_msg->dn = samba_dsdb_dn;
 417
 418                         ldb_msg_add_empty(features_msg, SAMBA_COMPATIBLE_FEATURES_ATTR,
 419                                           LDB_FLAG_MOD_DELETE, &features_el);
 420
 421                         if (samba_options_supported == 1) {
 422                                 for (i = 0;
 423                                      old_compatibleFeatures && i < old_compatibleFeatures->num_values;
 424                                      i++) {
 425                                         for (j = 0;
 426                                              j < ARRAY_SIZE(current_supportedFeatures); j++) {
 427                                                 if (strcmp((char *)old_compatibleFeatures->values[i].data,
 428                                                            current_supportedFeatures[j]) == 0) {
 429                                                         break;
 430                                                 }
 431                                         }
 432                                         if (j == ARRAY_SIZE(current_supportedFeatures)) {
 433                                                 /*
 434                                                  * Add to list of features to remove
 435                                                  * (rather than all features)
 436                                                  */
 437                                                 ret = ldb_msg_add_value(features_msg, SAMBA_COMPATIBLE_FEATURES_ATTR,
 438                                                                         &old_compatibleFeatures->values[i],
 439                                                                         NULL);
 440                                                 if (ret != LDB_SUCCESS) {
 441                                                         return ret;
 442                                                 }
 443                                         }
 444                                 }
 445
 446                                 if (features_el->num_values > 0) {
 447                                         /* Delete by list */
 448                                         ret = ldb_next_start_trans(module);
 449                                         if (ret != LDB_SUCCESS) {
 450                                                 return ret;
 451                                         }
 452                                         ret = dsdb_module_modify(module, features_msg, DSDB_FLAG_NEXT_MODULE, NULL);
 453                                         if (ret != LDB_SUCCESS) {
 454                                                 ldb_next_del_trans(module);
 455                                                 return ret;
 456                                         }
 457                                         ret = ldb_next_end_trans(module);
 458                                         if (ret != LDB_SUCCESS) {
 459                                                 return ret;
 460                                         }
 461                                 }
 462                         } else {
 463                                 /* Delete all */
 464                                 ret = ldb_next_start_trans(module);
 465                                 if (ret != LDB_SUCCESS) {
 466                                         return ret;
 467                                 }
 468                                 ret = dsdb_module_modify(module, features_msg, DSDB_FLAG_NEXT_MODULE, NULL);
 469                                 if (ret != LDB_SUCCESS) {
 470                                         ldb_next_del_trans(module);
 471                                         return ret;
 472                                 }
 473                                 ret = ldb_next_end_trans(module);
 474                                 if (ret != LDB_SUCCESS) {
 475                                         return ret;
 476                                 }
 477                         }
 478                 }
 479
 480         } else {
 481                 talloc_free(tmp_ctx);
 482                 return ret;
 483         }
 484
 485         backend_modules = NULL;
 486         if (strcasecmp(backendType, "ldb") == 0) {
 487                 extended_dn_module = extended_dn_module_ldb;
 488                 link_modules = tdb_modules_list;
 489         } else {
 490                 struct cli_credentials *cred;
 491                 bool is_ldapi = false;
 492
 493                 ret = dsdb_module_search_dn(module, tmp_ctx, &res, partition_dn,
 494                                             partition_attrs, DSDB_FLAG_NEXT_MODULE, NULL);
 495                 if (ret == LDB_SUCCESS) {
 496                         backendUrl = ldb_msg_find_attr_as_string(res->msgs[0], "ldapBackend", "ldapi://");
 497                         if (!strncasecmp(backendUrl, "ldapi://", sizeof("ldapi://")-1)) {
 498                                 is_ldapi = true;
 499                         }
 500                 } else if (ret != LDB_ERR_NO_SUCH_OBJECT) {
 501                         talloc_free(tmp_ctx);
 502                         return ret;
 503                 }
 504                 if (strcasecmp(backendType, "fedora-ds") == 0) {
 505                         link_modules = fedora_ds_modules;
 506                         backend_modules = fedora_ds_backend_modules;
 507                         extended_dn_module = extended_dn_module_fds;
 508                 } else if (strcasecmp(backendType, "openldap") == 0) {
 509                         link_modules = openldap_modules;
 510                         backend_modules = openldap_backend_modules;
 511                         extended_dn_module = extended_dn_module_openldap;
 512                         extended_dn_in_module = "extended_dn_in_openldap";
 513                         if (is_ldapi) {
 514                                 use_sasl_external = true;
 515                         }
 516                 } else {
 517                         return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR, "invalid backend type");
 518                 }
 519                 ret = ldb_set_opaque(ldb, "readOnlySchema", (void*)1);
 520                 if (ret != LDB_SUCCESS) {
 521                         ldb_set_errstring(ldb, "Failed to set readOnlySchema opaque");
 522                 }
 523
 524                 cred = ldb_get_opaque(ldb, "credentials");
 525                 if (!cred || !cli_credentials_authentication_requested(cred)) {
 526                         ret = set_ldap_credentials(ldb, use_sasl_external);
 527                         if (ret != LDB_SUCCESS) {
 528                                 return ret;
 529                         }
 530                 }
 531         }
 532
 533 #define CHECK_MODULE_LIST \
 534         do {                                                    \
 535                 if (!final_module_list) {                       \
 536                         talloc_free(tmp_ctx);                   \
 537                         return ldb_oom(ldb);                    \
 538                 }                                               \
 539         } while (0)
 540
 541         final_module_list = str_list_copy_const(tmp_ctx, modules_list1);
 542         CHECK_MODULE_LIST;
 543
 544         final_module_list = str_list_add_const(final_module_list, extended_dn_in_module);
 545         CHECK_MODULE_LIST;
 546
 547         final_module_list = str_list_append_const(final_module_list, modules_list1a);
 548         CHECK_MODULE_LIST;
 549
 550         final_module_list = str_list_append_const(final_module_list, link_modules);
 551         CHECK_MODULE_LIST;
 552
 553         final_module_list = str_list_add_const(final_module_list, extended_dn_module);
 554         CHECK_MODULE_LIST;
 555
 556         final_module_list = str_list_append_const(final_module_list, modules_list2);
 557         CHECK_MODULE_LIST;
 558
 559
 560         ret = read_at_rootdse_record(ldb, module, tmp_ctx, &rootdse_msg, NULL);
 561         CHECK_LDB_RET(ret);
 562
 563         partition_msg = ldb_msg_new(tmp_ctx);
 564         partition_msg->dn = ldb_dn_new(partition_msg, ldb, "@" DSDB_OPAQUE_PARTITION_MODULE_MSG_OPAQUE_NAME);
 565
 566         ret = prepare_modules_line(ldb, tmp_ctx,
 567                                    rootdse_msg,
 568                                    partition_msg, "schemaNamingContext",
 569                                    "schema_data", backend_modules);
 570         CHECK_LDB_RET(ret);
 571
 572         ret = prepare_modules_line(ldb, tmp_ctx,
 573                                    rootdse_msg,
 574                                    partition_msg, NULL,
 575                                    NULL, backend_modules);
 576         CHECK_LDB_RET(ret);
 577
 578         ret = ldb_set_opaque(ldb, DSDB_OPAQUE_PARTITION_MODULE_MSG_OPAQUE_NAME, partition_msg);
 579         CHECK_LDB_RET(ret);
 580
 581         talloc_steal(ldb, partition_msg);
 582
 583         /* Now prepare the module chain.  Oddly, we must give it to ldb_load_modules_list in REVERSE */
 584         for (len = 0; final_module_list[len]; len++) { /* noop */};
 585
 586         reverse_module_list = talloc_array(tmp_ctx, const char *, len+1);
 587         if (!reverse_module_list) {
 588                 talloc_free(tmp_ctx);
 589                 return ldb_oom(ldb);
 590         }
 591         for (i=0; i < len; i++) {
 592                 reverse_module_list[i] = final_module_list[(len - 1) - i];
 593         }
 594         reverse_module_list[i] = NULL;
 595
 596         /* The backend (at least until the partitions module
 597          * reconfigures things) is the next module in the currently
 598          * loaded chain */
 599         backend_module = ldb_module_next(module);
 600         ret = ldb_module_load_list(ldb, reverse_module_list, backend_module, &module_chain);
 601         CHECK_LDB_RET(ret);
 602
 603         talloc_free(tmp_ctx);
 604         /* Set this as the 'next' module, so that we effectivly append it to module chain */
 605         ldb_module_set_next(module, module_chain);
 606
 607         return ldb_next_init(module);
 608 }
 609
 610 static const struct ldb_module_ops ldb_samba_dsdb_module_ops = {
 611         .name              = "samba_dsdb",
 612         .init_context      = samba_dsdb_init,
 613 };
 614
 615 static struct ldb_message *dsdb_flags_ignore_fixup(TALLOC_CTX *mem_ctx,
 616                                                 const struct ldb_message *_msg)
 617 {
 618         struct ldb_message *msg = NULL;
 619         unsigned int i;
 620
 621         /* we have to copy the message as the caller might have it as a const */
 622         msg = ldb_msg_copy_shallow(mem_ctx, _msg);
 623         if (msg == NULL) {
 624                 return NULL;
 625         }
 626
 627         for (i=0; i < msg->num_elements;) {
 628                 struct ldb_message_element *e = &msg->elements[i];
 629
 630                 if (!(e->flags & DSDB_FLAG_INTERNAL_FORCE_META_DATA)) {
 631                         i++;
 632                         continue;
 633                 }
 634
 635                 e->flags &= ~DSDB_FLAG_INTERNAL_FORCE_META_DATA;
 636
 637                 if (e->num_values != 0) {
 638                         i++;
 639                         continue;
 640                 }
 641
 642                 ldb_msg_remove_element(msg, e);
 643         }
 644
 645         return msg;
 646 }
 647
 648 static int dsdb_flags_ignore_add(struct ldb_module *module, struct ldb_request *req)
 649 {
 650         struct ldb_context *ldb = ldb_module_get_ctx(module);
 651         struct ldb_request *down_req = NULL;
 652         struct ldb_message *msg = NULL;
 653         int ret;
 654
 655         msg = dsdb_flags_ignore_fixup(req, req->op.add.message);
 656         if (msg == NULL) {
 657                 return ldb_module_oom(module);
 658         }
 659
 660         ret = ldb_build_add_req(&down_req, ldb, req,
 661                                 msg,
 662                                 req->controls,
 663                                 req, dsdb_next_callback,
 664                                 req);
 665         LDB_REQ_SET_LOCATION(down_req);
 666         if (ret != LDB_SUCCESS) {
 667                 return ret;
 668         }
 669
 670         /* go on with the call chain */
 671         return ldb_next_request(module, down_req);
 672 }
 673
 674 static int dsdb_flags_ignore_modify(struct ldb_module *module, struct ldb_request *req)
 675 {
 676         struct ldb_context *ldb = ldb_module_get_ctx(module);
 677         struct ldb_request *down_req = NULL;
 678         struct ldb_message *msg = NULL;
 679         int ret;
 680
 681         msg = dsdb_flags_ignore_fixup(req, req->op.mod.message);
 682         if (msg == NULL) {
 683                 return ldb_module_oom(module);
 684         }
 685
 686         ret = ldb_build_mod_req(&down_req, ldb, req,
 687                                 msg,
 688                                 req->controls,
 689                                 req, dsdb_next_callback,
 690                                 req);
 691         LDB_REQ_SET_LOCATION(down_req);
 692         if (ret != LDB_SUCCESS) {
 693                 return ret;
 694         }
 695
 696         /* go on with the call chain */
 697         return ldb_next_request(module, down_req);
 698 }
 699
 700 static const struct ldb_module_ops ldb_dsdb_flags_ignore_module_ops = {
 701         .name   = "dsdb_flags_ignore",
 702         .add    = dsdb_flags_ignore_add,
 703         .modify = dsdb_flags_ignore_modify,
 704 };
 705
 706 int ldb_samba_dsdb_module_init(const char *version)
 707 {
 708         int ret;
 709         LDB_MODULE_CHECK_VERSION(version);
 710         ret = ldb_register_module(&ldb_samba_dsdb_module_ops);
 711         if (ret != LDB_SUCCESS) {
 712                 return ret;
 713         }
 714         ret = ldb_register_module(&ldb_dsdb_flags_ignore_module_ops);
 715         if (ret != LDB_SUCCESS) {
 716                 return ret;
 717         }
 718         return LDB_SUCCESS;
 719 }