source4/dsdb/samdb/ldb_modules/acl.c

   1 /*
   2   ldb database library
   3
   4   Copyright (C) Simo Sorce 2006-2008
   5   Copyright (C) Nadezhda Ivanova 2009
   6   Copyright (C) Anatoliy Atanasov  2009
   7
   8   This program is free software; you can redistribute it and/or modify
   9   it under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 3 of the License, or
  11   (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 /*
  23  *  Name: ldb
  24  *
  25  *  Component: ldb ACL module
  26  *
  27  *  Description: Module that performs authorisation access checks based on the
  28  *               account's security context and the DACL of the object being polled.
  29  *               Only DACL checks implemented at this point
  30  *
  31  *  Authors: Nadezhda Ivanova, Anatoliy Atanasov
  32  */
  33
  34 #include "includes.h"
  35 #include "ldb_module.h"
  36 #include "auth/auth.h"
  37 #include "libcli/security/security.h"
  38 #include "dsdb/samdb/samdb.h"
  39 #include "librpc/gen_ndr/ndr_security.h"
  40 #include "param/param.h"
  41 #include "dsdb/samdb/ldb_modules/util.h"
  42 #include "lib/util/tsort.h"
  43 #include "system/kerberos.h"
  44 #include "auth/kerberos/kerberos.h"
  45
  46 struct extended_access_check_attribute {
  47         const char *oa_name;
  48         const uint32_t requires_rights;
  49 };
  50
  51 struct acl_private {
  52         bool acl_search;
  53         const char **password_attrs;
  54         void *cached_schema_ptr;
  55         uint64_t cached_schema_metadata_usn;
  56         uint64_t cached_schema_loaded_usn;
  57         const char **confidential_attrs;
  58 };
  59
  60 struct acl_context {
  61         struct ldb_module *module;
  62         struct ldb_request *req;
  63         bool am_system;
  64         bool am_administrator;
  65         bool modify_search;
  66         bool constructed_attrs;
  67         bool allowedAttributes;
  68         bool allowedAttributesEffective;
  69         bool allowedChildClasses;
  70         bool allowedChildClassesEffective;
  71         bool sDRightsEffective;
  72         bool userPassword;
  73         const char * const *attrs;
  74         struct dsdb_schema *schema;
  75 };
  76
  77 static int acl_module_init(struct ldb_module *module)
  78 {
  79         struct ldb_context *ldb;
  80         struct acl_private *data;
  81         int ret;
  82         unsigned int i, n, j;
  83         TALLOC_CTX *mem_ctx;
  84         static const char * const attrs[] = { "passwordAttribute", NULL };
  85         static const char * const secret_attrs[] = {
  86                 DSDB_SECRET_ATTRIBUTES
  87         };
  88         struct ldb_result *res;
  89         struct ldb_message *msg;
  90         struct ldb_message_element *password_attributes;
  91
  92         ldb = ldb_module_get_ctx(module);
  93
  94         ret = ldb_mod_register_control(module, LDB_CONTROL_SD_FLAGS_OID);
  95         if (ret != LDB_SUCCESS) {
  96                 ldb_debug(ldb, LDB_DEBUG_ERROR,
  97                           "acl_module_init: Unable to register control with rootdse!\n");
  98                 return ldb_operr(ldb);
  99         }
 100
 101         data = talloc_zero(module, struct acl_private);
 102         if (data == NULL) {
 103                 return ldb_oom(ldb);
 104         }
 105
 106         data->acl_search = lpcfg_parm_bool(ldb_get_opaque(ldb, "loadparm"),
 107                                         NULL, "acl", "search", true);
 108         ldb_module_set_private(module, data);
 109
 110         mem_ctx = talloc_new(module);
 111         if (!mem_ctx) {
 112                 return ldb_oom(ldb);
 113         }
 114
 115         ret = dsdb_module_search_dn(module, mem_ctx, &res,
 116                                     ldb_dn_new(mem_ctx, ldb, "@KLUDGEACL"),
 117                                     attrs,
 118                                     DSDB_FLAG_NEXT_MODULE |
 119                                     DSDB_FLAG_AS_SYSTEM,
 120                                     NULL);
 121         if (ret != LDB_SUCCESS) {
 122                 goto done;
 123         }
 124         if (res->count == 0) {
 125                 goto done;
 126         }
 127
 128         if (res->count > 1) {
 129                 talloc_free(mem_ctx);
 130                 return LDB_ERR_CONSTRAINT_VIOLATION;
 131         }
 132
 133         msg = res->msgs[0];
 134
 135         password_attributes = ldb_msg_find_element(msg, "passwordAttribute");
 136         if (!password_attributes) {
 137                 goto done;
 138         }
 139         data->password_attrs = talloc_array(data, const char *,
 140                         password_attributes->num_values +
 141                         ARRAY_SIZE(secret_attrs) + 1);
 142         if (!data->password_attrs) {
 143                 talloc_free(mem_ctx);
 144                 return ldb_oom(ldb);
 145         }
 146
 147         n = 0;
 148         for (i=0; i < password_attributes->num_values; i++) {
 149                 data->password_attrs[n] = (const char *)password_attributes->values[i].data;
 150                 talloc_steal(data->password_attrs, password_attributes->values[i].data);
 151                 n++;
 152         }
 153
 154         for (i=0; i < ARRAY_SIZE(secret_attrs); i++) {
 155                 bool found = false;
 156
 157                 for (j=0; j < n; j++) {
 158                         if (strcasecmp(data->password_attrs[j], secret_attrs[i]) == 0) {
 159                                 found = true;
 160                                 break;
 161                         }
 162                 }
 163
 164                 if (found) {
 165                         continue;
 166                 }
 167
 168                 data->password_attrs[n] = talloc_strdup(data->password_attrs,
 169                                                         secret_attrs[i]);
 170                 if (data->password_attrs[n] == NULL) {
 171                         talloc_free(mem_ctx);
 172                         return ldb_oom(ldb);
 173                 }
 174                 n++;
 175         }
 176         data->password_attrs[n] = NULL;
 177
 178 done:
 179         talloc_free(mem_ctx);
 180         return ldb_next_init(module);
 181 }
 182
 183 static int acl_allowedAttributes(struct ldb_module *module,
 184                                  const struct dsdb_schema *schema,
 185                                  struct ldb_message *sd_msg,
 186                                  struct ldb_message *msg,
 187                                  struct acl_context *ac)
 188 {
 189         struct ldb_message_element *oc_el;
 190         struct ldb_context *ldb = ldb_module_get_ctx(module);
 191         TALLOC_CTX *mem_ctx;
 192         const char **attr_list;
 193         int i, ret;
 194         const struct dsdb_class *objectclass;
 195
 196         /* If we don't have a schema yet, we can't do anything... */
 197         if (schema == NULL) {
 198                 ldb_asprintf_errstring(ldb, "cannot add allowedAttributes to %s because no schema is loaded", ldb_dn_get_linearized(msg->dn));
 199                 return LDB_ERR_OPERATIONS_ERROR;
 200         }
 201
 202         /* Must remove any existing attribute */
 203         if (ac->allowedAttributes) {
 204                 ldb_msg_remove_attr(msg, "allowedAttributes");
 205         }
 206
 207         mem_ctx = talloc_new(msg);
 208         if (!mem_ctx) {
 209                 return ldb_oom(ldb);
 210         }
 211
 212         oc_el = ldb_msg_find_element(sd_msg, "objectClass");
 213         attr_list = dsdb_full_attribute_list(mem_ctx, schema, oc_el, DSDB_SCHEMA_ALL);
 214         if (!attr_list) {
 215                 ldb_asprintf_errstring(ldb, "acl: Failed to get list of attributes");
 216                 talloc_free(mem_ctx);
 217                 return LDB_ERR_OPERATIONS_ERROR;
 218         }
 219
 220         /*
 221          * Get the top-most structural object class for the ACL check
 222          */
 223         objectclass = dsdb_get_last_structural_class(ac->schema,
 224                                                      oc_el);
 225         if (objectclass == NULL) {
 226                 ldb_asprintf_errstring(ldb, "acl_read: Failed to find a structural class for %s",
 227                                        ldb_dn_get_linearized(sd_msg->dn));
 228                 talloc_free(mem_ctx);
 229                 return LDB_ERR_OPERATIONS_ERROR;
 230         }
 231
 232         if (ac->allowedAttributes) {
 233                 for (i=0; attr_list && attr_list[i]; i++) {
 234                         ldb_msg_add_string(msg, "allowedAttributes", attr_list[i]);
 235                 }
 236         }
 237         if (ac->allowedAttributesEffective) {
 238                 struct security_descriptor *sd;
 239                 struct dom_sid *sid = NULL;
 240                 struct ldb_control *as_system = ldb_request_get_control(ac->req,
 241                                                                         LDB_CONTROL_AS_SYSTEM_OID);
 242
 243                 if (as_system != NULL) {
 244                         as_system->critical = 0;
 245                 }
 246
 247                 ldb_msg_remove_attr(msg, "allowedAttributesEffective");
 248                 if (ac->am_system || as_system) {
 249                         for (i=0; attr_list && attr_list[i]; i++) {
 250                                 ldb_msg_add_string(msg, "allowedAttributesEffective", attr_list[i]);
 251                         }
 252                         return LDB_SUCCESS;
 253                 }
 254
 255                 ret = dsdb_get_sd_from_ldb_message(ldb_module_get_ctx(module), mem_ctx, sd_msg, &sd);
 256
 257                 if (ret != LDB_SUCCESS) {
 258                         return ret;
 259                 }
 260
 261                 sid = samdb_result_dom_sid(mem_ctx, sd_msg, "objectSid");
 262                 for (i=0; attr_list && attr_list[i]; i++) {
 263                         const struct dsdb_attribute *attr = dsdb_attribute_by_lDAPDisplayName(schema,
 264                                                                                         attr_list[i]);
 265                         if (!attr) {
 266                                 return ldb_operr(ldb);
 267                         }
 268                         /* remove constructed attributes */
 269                         if (attr->systemFlags & DS_FLAG_ATTR_IS_CONSTRUCTED
 270                             || attr->systemOnly
 271                             || (attr->linkID != 0 && attr->linkID % 2 != 0 )) {
 272                                 continue;
 273                         }
 274                         ret = acl_check_access_on_attribute(module,
 275                                                             msg,
 276                                                             sd,
 277                                                             sid,
 278                                                             SEC_ADS_WRITE_PROP,
 279                                                             attr,
 280                                                             objectclass);
 281                         if (ret == LDB_SUCCESS) {
 282                                 ldb_msg_add_string(msg, "allowedAttributesEffective", attr_list[i]);
 283                         }
 284                 }
 285         }
 286         return LDB_SUCCESS;
 287 }
 288
 289 static int acl_childClasses(struct ldb_module *module,
 290                             const struct dsdb_schema *schema,
 291                             struct ldb_message *sd_msg,
 292                             struct ldb_message *msg,
 293                             const char *attrName)
 294 {
 295         struct ldb_message_element *oc_el;
 296         struct ldb_message_element *allowedClasses;
 297         const struct dsdb_class *sclass;
 298         unsigned int i, j;
 299         int ret;
 300
 301         /* If we don't have a schema yet, we can't do anything... */
 302         if (schema == NULL) {
 303                 ldb_asprintf_errstring(ldb_module_get_ctx(module), "cannot add childClassesEffective to %s because no schema is loaded", ldb_dn_get_linearized(msg->dn));
 304                 return LDB_ERR_OPERATIONS_ERROR;
 305         }
 306
 307         /* Must remove any existing attribute, or else confusion reins */
 308         ldb_msg_remove_attr(msg, attrName);
 309         ret = ldb_msg_add_empty(msg, attrName, 0, &allowedClasses);
 310         if (ret != LDB_SUCCESS) {
 311                 return ret;
 312         }
 313
 314         oc_el = ldb_msg_find_element(sd_msg, "objectClass");
 315
 316         for (i=0; oc_el && i < oc_el->num_values; i++) {
 317                 sclass = dsdb_class_by_lDAPDisplayName_ldb_val(schema, &oc_el->values[i]);
 318                 if (!sclass) {
 319                         /* We don't know this class?  what is going on? */
 320                         continue;
 321                 }
 322
 323                 for (j=0; sclass->possibleInferiors && sclass->possibleInferiors[j]; j++) {
 324                         ldb_msg_add_string(msg, attrName, sclass->possibleInferiors[j]);
 325                 }
 326         }
 327         if (allowedClasses->num_values > 1) {
 328                 TYPESAFE_QSORT(allowedClasses->values, allowedClasses->num_values, data_blob_cmp);
 329                 for (i=1 ; i < allowedClasses->num_values; i++) {
 330                         struct ldb_val *val1 = &allowedClasses->values[i-1];
 331                         struct ldb_val *val2 = &allowedClasses->values[i];
 332                         if (data_blob_cmp(val1, val2) == 0) {
 333                                 memmove(val1, val2, (allowedClasses->num_values - i) * sizeof(struct ldb_val));
 334                                 allowedClasses->num_values--;
 335                                 i--;
 336                         }
 337                 }
 338         }
 339
 340         return LDB_SUCCESS;
 341 }
 342
 343 static int acl_check_access_on_class(struct ldb_module *module,
 344                                      const struct dsdb_schema *schema,
 345                                      TALLOC_CTX *mem_ctx,
 346                                      struct security_descriptor *sd,
 347                                      struct security_token *token,
 348                                      struct dom_sid *rp_sid,
 349                                      uint32_t access_mask,
 350                                      const char *class_name)
 351 {
 352         int ret;
 353         NTSTATUS status;
 354         uint32_t access_granted;
 355         struct object_tree *root = NULL;
 356         struct object_tree *new_node = NULL;
 357         const struct GUID *guid;
 358
 359         if (class_name != NULL) {
 360                 guid = class_schemaid_guid_by_lDAPDisplayName(schema, class_name);
 361                 if (!guid) {
 362                         DEBUG(10, ("acl_search: cannot find class %s\n",
 363                                    class_name));
 364                         goto fail;
 365                 }
 366                 if (!insert_in_object_tree(mem_ctx,
 367                                            guid, access_mask,
 368                                            &root, &new_node)) {
 369                         DEBUG(10, ("acl_search: cannot add to object tree guid\n"));
 370                         goto fail;
 371                 }
 372         }
 373
 374         status = sec_access_check_ds(sd, token,
 375                                      access_mask,
 376                                      &access_granted,
 377                                      root,
 378                                      rp_sid);
 379         if (!NT_STATUS_IS_OK(status)) {
 380                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 381         } else {
 382                 ret = LDB_SUCCESS;
 383         }
 384         return ret;
 385 fail:
 386         return ldb_operr(ldb_module_get_ctx(module));
 387 }
 388
 389 static int acl_childClassesEffective(struct ldb_module *module,
 390                                      const struct dsdb_schema *schema,
 391                                      struct ldb_message *sd_msg,
 392                                      struct ldb_message *msg,
 393                                      struct acl_context *ac)
 394 {
 395         struct ldb_message_element *oc_el;
 396         struct ldb_message_element *allowedClasses = NULL;
 397         const struct dsdb_class *sclass;
 398         struct security_descriptor *sd;
 399         struct ldb_control *as_system = ldb_request_get_control(ac->req,
 400                                                                 LDB_CONTROL_AS_SYSTEM_OID);
 401         struct dom_sid *sid = NULL;
 402         unsigned int i, j;
 403         int ret;
 404
 405         if (as_system != NULL) {
 406                 as_system->critical = 0;
 407         }
 408
 409         if (ac->am_system || as_system) {
 410                 return acl_childClasses(module, schema, sd_msg, msg, "allowedChildClassesEffective");
 411         }
 412
 413         /* If we don't have a schema yet, we can't do anything... */
 414         if (schema == NULL) {
 415                 ldb_asprintf_errstring(ldb_module_get_ctx(module), "cannot add allowedChildClassesEffective to %s because no schema is loaded", ldb_dn_get_linearized(msg->dn));
 416                 return LDB_ERR_OPERATIONS_ERROR;
 417         }
 418
 419         /* Must remove any existing attribute, or else confusion reins */
 420         ldb_msg_remove_attr(msg, "allowedChildClassesEffective");
 421
 422         oc_el = ldb_msg_find_element(sd_msg, "objectClass");
 423         ret = dsdb_get_sd_from_ldb_message(ldb_module_get_ctx(module), msg, sd_msg, &sd);
 424         if (ret != LDB_SUCCESS) {
 425                 return ret;
 426         }
 427
 428         sid = samdb_result_dom_sid(msg, sd_msg, "objectSid");
 429         for (i=0; oc_el && i < oc_el->num_values; i++) {
 430                 sclass = dsdb_class_by_lDAPDisplayName_ldb_val(schema, &oc_el->values[i]);
 431                 if (!sclass) {
 432                         /* We don't know this class?  what is going on? */
 433                         continue;
 434                 }
 435
 436                 for (j=0; sclass->possibleInferiors && sclass->possibleInferiors[j]; j++) {
 437                         const struct dsdb_class *sc;
 438
 439                         sc = dsdb_class_by_lDAPDisplayName(schema,
 440                                                            sclass->possibleInferiors[j]);
 441                         if (!sc) {
 442                                 /* We don't know this class?  what is going on? */
 443                                 continue;
 444                         }
 445
 446                         ret = acl_check_access_on_objectclass(module, ac,
 447                                                               sd, sid,
 448                                                               SEC_ADS_CREATE_CHILD,
 449                                                               sc);
 450                         if (ret == LDB_SUCCESS) {
 451                                 ldb_msg_add_string(msg, "allowedChildClassesEffective",
 452                                                    sclass->possibleInferiors[j]);
 453                         }
 454                 }
 455         }
 456         allowedClasses = ldb_msg_find_element(msg, "allowedChildClassesEffective");
 457         if (!allowedClasses) {
 458                 return LDB_SUCCESS;
 459         }
 460
 461         if (allowedClasses->num_values > 1) {
 462                 TYPESAFE_QSORT(allowedClasses->values, allowedClasses->num_values, data_blob_cmp);
 463                 for (i=1 ; i < allowedClasses->num_values; i++) {
 464                         struct ldb_val *val1 = &allowedClasses->values[i-1];
 465                         struct ldb_val *val2 = &allowedClasses->values[i];
 466                         if (data_blob_cmp(val1, val2) == 0) {
 467                                 memmove(val1, val2, (allowedClasses->num_values - i) * sizeof( struct ldb_val));
 468                                 allowedClasses->num_values--;
 469                                 i--;
 470                         }
 471                 }
 472         }
 473         return LDB_SUCCESS;
 474 }
 475
 476 static int acl_sDRightsEffective(struct ldb_module *module,
 477                                  struct ldb_message *sd_msg,
 478                                  struct ldb_message *msg,
 479                                  struct acl_context *ac)
 480 {
 481         struct ldb_context *ldb = ldb_module_get_ctx(module);
 482         struct ldb_message_element *rightsEffective;
 483         int ret;
 484         struct security_descriptor *sd;
 485         struct ldb_control *as_system = ldb_request_get_control(ac->req,
 486                                                                 LDB_CONTROL_AS_SYSTEM_OID);
 487         struct dom_sid *sid = NULL;
 488         uint32_t flags = 0;
 489
 490         if (as_system != NULL) {
 491                 as_system->critical = 0;
 492         }
 493
 494         /* Must remove any existing attribute, or else confusion reins */
 495         ldb_msg_remove_attr(msg, "sDRightsEffective");
 496         ret = ldb_msg_add_empty(msg, "sDRightsEffective", 0, &rightsEffective);
 497         if (ret != LDB_SUCCESS) {
 498                 return ret;
 499         }
 500         if (ac->am_system || as_system) {
 501                 flags = SECINFO_OWNER | SECINFO_GROUP |  SECINFO_SACL |  SECINFO_DACL;
 502         } else {
 503                 const struct dsdb_class *objectclass;
 504                 const struct dsdb_attribute *attr;
 505
 506                 objectclass = dsdb_get_structural_oc_from_msg(ac->schema, sd_msg);
 507                 if (objectclass == NULL) {
 508                         return ldb_operr(ldb);
 509                 }
 510
 511                 attr = dsdb_attribute_by_lDAPDisplayName(ac->schema,
 512                                                          "nTSecurityDescriptor");
 513                 if (attr == NULL) {
 514                         return ldb_operr(ldb);
 515                 }
 516
 517                 /* Get the security descriptor from the message */
 518                 ret = dsdb_get_sd_from_ldb_message(ldb, msg, sd_msg, &sd);
 519                 if (ret != LDB_SUCCESS) {
 520                         return ret;
 521                 }
 522                 sid = samdb_result_dom_sid(msg, sd_msg, "objectSid");
 523                 ret = acl_check_access_on_attribute(module,
 524                                                     msg,
 525                                                     sd,
 526                                                     sid,
 527                                                     SEC_STD_WRITE_OWNER,
 528                                                     attr,
 529                                                     objectclass);
 530                 if (ret == LDB_SUCCESS) {
 531                         flags |= SECINFO_OWNER | SECINFO_GROUP;
 532                 }
 533                 ret = acl_check_access_on_attribute(module,
 534                                                     msg,
 535                                                     sd,
 536                                                     sid,
 537                                                     SEC_STD_WRITE_DAC,
 538                                                     attr,
 539                                                     objectclass);
 540                 if (ret == LDB_SUCCESS) {
 541                         flags |= SECINFO_DACL;
 542                 }
 543                 ret = acl_check_access_on_attribute(module,
 544                                                     msg,
 545                                                     sd,
 546                                                     sid,
 547                                                     SEC_FLAG_SYSTEM_SECURITY,
 548                                                     attr,
 549                                                     objectclass);
 550                 if (ret == LDB_SUCCESS) {
 551                         flags |= SECINFO_SACL;
 552                 }
 553         }
 554         return samdb_msg_add_uint(ldb_module_get_ctx(module), msg, msg,
 555                                   "sDRightsEffective", flags);
 556 }
 557
 558 static int acl_validate_spn_value(TALLOC_CTX *mem_ctx,
 559                                   struct ldb_context *ldb,
 560                                   const char *spn_value,
 561                                   uint32_t userAccountControl,
 562                                   const char *samAccountName,
 563                                   const char *dnsHostName,
 564                                   const char *netbios_name,
 565                                   const char *ntds_guid)
 566 {
 567         int ret;
 568         krb5_context krb_ctx;
 569         krb5_error_code kerr;
 570         krb5_principal principal;
 571         char *instanceName;
 572         char *serviceType;
 573         char *serviceName;
 574         const char *forest_name = samdb_forest_name(ldb, mem_ctx);
 575         const char *base_domain = samdb_default_domain_name(ldb, mem_ctx);
 576         struct loadparm_context *lp_ctx = talloc_get_type(ldb_get_opaque(ldb, "loadparm"),
 577                                                           struct loadparm_context);
 578         bool is_dc = (userAccountControl & UF_SERVER_TRUST_ACCOUNT) ||
 579                 (userAccountControl & UF_PARTIAL_SECRETS_ACCOUNT);
 580
 581         if (strcasecmp_m(spn_value, samAccountName) == 0) {
 582                 /* MacOS X sets this value, and setting an SPN of your
 583                  * own samAccountName is both pointless and safe */
 584                 return LDB_SUCCESS;
 585         }
 586
 587         kerr = smb_krb5_init_context_basic(mem_ctx,
 588                                            lp_ctx,
 589                                            &krb_ctx);
 590         if (kerr != 0) {
 591                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 592                                  "Could not initialize kerberos context.");
 593         }
 594
 595         ret = krb5_parse_name(krb_ctx, spn_value, &principal);
 596         if (ret) {
 597                 krb5_free_context(krb_ctx);
 598                 return LDB_ERR_CONSTRAINT_VIOLATION;
 599         }
 600
 601         if (principal->name.name_string.len < 2) {
 602                 goto fail;
 603         }
 604
 605         instanceName = principal->name.name_string.val[1];
 606         serviceType = principal->name.name_string.val[0];
 607         if (principal->name.name_string.len == 3) {
 608                 serviceName = principal->name.name_string.val[2];
 609         } else {
 610                 serviceName = NULL;
 611         }
 612
 613         if (serviceName) {
 614                 if (!is_dc) {
 615                         goto fail;
 616                 }
 617                 if (strcasecmp(serviceType, "ldap") == 0) {
 618                         if (strcasecmp(serviceName, netbios_name) != 0 &&
 619                             strcasecmp(serviceName, forest_name) != 0) {
 620                                 goto fail;
 621                         }
 622
 623                 } else if (strcasecmp(serviceType, "gc") == 0) {
 624                         if (strcasecmp(serviceName, forest_name) != 0) {
 625                                 goto fail;
 626                         }
 627                 } else {
 628                         if (strcasecmp(serviceName, base_domain) != 0 &&
 629                             strcasecmp(serviceName, netbios_name) != 0) {
 630                                 goto fail;
 631                         }
 632                 }
 633         }
 634         /* instanceName can be samAccountName without $ or dnsHostName
 635          * or "ntds_guid._msdcs.forest_domain for DC objects */
 636         if (strlen(instanceName) == (strlen(samAccountName) - 1)
 637             && strncasecmp(instanceName, samAccountName, strlen(samAccountName) - 1) == 0) {
 638                 goto success;
 639         } else if (dnsHostName != NULL && strcasecmp(instanceName, dnsHostName) == 0) {
 640                 goto success;
 641         } else if (is_dc) {
 642                 const char *guid_str;
 643                 guid_str = talloc_asprintf(mem_ctx,"%s._msdcs.%s",
 644                                            ntds_guid,
 645                                            forest_name);
 646                 if (strcasecmp(instanceName, guid_str) == 0) {
 647                         goto success;
 648                 }
 649         }
 650
 651 fail:
 652         krb5_free_principal(krb_ctx, principal);
 653         krb5_free_context(krb_ctx);
 654         return LDB_ERR_CONSTRAINT_VIOLATION;
 655
 656 success:
 657         krb5_free_principal(krb_ctx, principal);
 658         krb5_free_context(krb_ctx);
 659         return LDB_SUCCESS;
 660 }
 661
 662 static int acl_check_spn(TALLOC_CTX *mem_ctx,
 663                          struct ldb_module *module,
 664                          struct ldb_request *req,
 665                          struct security_descriptor *sd,
 666                          struct dom_sid *sid,
 667                          const struct dsdb_attribute *attr,
 668                          const struct dsdb_class *objectclass)
 669 {
 670         int ret;
 671         unsigned int i;
 672         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 673         struct ldb_context *ldb = ldb_module_get_ctx(module);
 674         struct ldb_result *acl_res;
 675         struct ldb_result *netbios_res;
 676         struct ldb_message_element *el;
 677         struct ldb_dn *partitions_dn = samdb_partitions_dn(ldb, tmp_ctx);
 678         uint32_t userAccountControl;
 679         const char *samAccountName;
 680         const char *dnsHostName;
 681         const char *netbios_name;
 682         struct GUID ntds;
 683         char *ntds_guid = NULL;
 684
 685         static const char *acl_attrs[] = {
 686                 "samAccountName",
 687                 "dnsHostName",
 688                 "userAccountControl",
 689                 NULL
 690         };
 691         static const char *netbios_attrs[] = {
 692                 "nETBIOSName",
 693                 NULL
 694         };
 695
 696         /* if we have wp, we can do whatever we like */
 697         if (acl_check_access_on_attribute(module,
 698                                           tmp_ctx,
 699                                           sd,
 700                                           sid,
 701                                           SEC_ADS_WRITE_PROP,
 702                                           attr, objectclass) == LDB_SUCCESS) {
 703                 talloc_free(tmp_ctx);
 704                 return LDB_SUCCESS;
 705         }
 706
 707         ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 708                                        GUID_DRS_VALIDATE_SPN,
 709                                        SEC_ADS_SELF_WRITE,
 710                                        sid);
 711
 712         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 713                 dsdb_acl_debug(sd, acl_user_token(module),
 714                                req->op.mod.message->dn,
 715                                true,
 716                                10);
 717                 talloc_free(tmp_ctx);
 718                 return ret;
 719         }
 720
 721         ret = dsdb_module_search_dn(module, tmp_ctx,
 722                                     &acl_res, req->op.mod.message->dn,
 723                                     acl_attrs,
 724                                     DSDB_FLAG_NEXT_MODULE |
 725                                     DSDB_FLAG_AS_SYSTEM |
 726                                     DSDB_SEARCH_SHOW_RECYCLED,
 727                                     req);
 728         if (ret != LDB_SUCCESS) {
 729                 talloc_free(tmp_ctx);
 730                 return ret;
 731         }
 732
 733         userAccountControl = ldb_msg_find_attr_as_uint(acl_res->msgs[0], "userAccountControl", 0);
 734         dnsHostName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "dnsHostName", NULL);
 735         samAccountName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "samAccountName", NULL);
 736
 737         ret = dsdb_module_search(module, tmp_ctx,
 738                                  &netbios_res, partitions_dn,
 739                                  LDB_SCOPE_ONELEVEL,
 740                                  netbios_attrs,
 741                                  DSDB_FLAG_NEXT_MODULE |
 742                                  DSDB_FLAG_AS_SYSTEM,
 743                                  req,
 744                                  "(ncName=%s)",
 745                                  ldb_dn_get_linearized(ldb_get_default_basedn(ldb)));
 746
 747         netbios_name = ldb_msg_find_attr_as_string(netbios_res->msgs[0], "nETBIOSName", NULL);
 748
 749         el = ldb_msg_find_element(req->op.mod.message, "servicePrincipalName");
 750         if (!el) {
 751                 talloc_free(tmp_ctx);
 752                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 753                                          "Error finding element for servicePrincipalName.");
 754         }
 755
 756         /* NTDSDSA objectGuid of object we are checking SPN for */
 757         if (userAccountControl & (UF_SERVER_TRUST_ACCOUNT | UF_PARTIAL_SECRETS_ACCOUNT)) {
 758                 ret = dsdb_module_find_ntdsguid_for_computer(module, tmp_ctx,
 759                                                              req->op.mod.message->dn, &ntds, req);
 760                 if (ret != LDB_SUCCESS) {
 761                         ldb_asprintf_errstring(ldb, "Failed to find NTDSDSA objectGuid for %s: %s",
 762                                                ldb_dn_get_linearized(req->op.mod.message->dn),
 763                                                ldb_strerror(ret));
 764                         talloc_free(tmp_ctx);
 765                         return LDB_ERR_OPERATIONS_ERROR;
 766                 }
 767                 ntds_guid = GUID_string(tmp_ctx, &ntds);
 768         }
 769
 770         for (i=0; i < el->num_values; i++) {
 771                 ret = acl_validate_spn_value(tmp_ctx,
 772                                              ldb,
 773                                              (char *)el->values[i].data,
 774                                              userAccountControl,
 775                                              samAccountName,
 776                                              dnsHostName,
 777                                              netbios_name,
 778                                              ntds_guid);
 779                 if (ret != LDB_SUCCESS) {
 780                         talloc_free(tmp_ctx);
 781                         return ret;
 782                 }
 783         }
 784         talloc_free(tmp_ctx);
 785         return LDB_SUCCESS;
 786 }
 787
 788 static int acl_add(struct ldb_module *module, struct ldb_request *req)
 789 {
 790         int ret;
 791         struct ldb_dn *parent;
 792         struct ldb_context *ldb;
 793         const struct dsdb_schema *schema;
 794         const struct dsdb_class *objectclass;
 795         struct ldb_dn *nc_root;
 796         struct ldb_control *as_system;
 797
 798         if (ldb_dn_is_special(req->op.add.message->dn)) {
 799                 return ldb_next_request(module, req);
 800         }
 801
 802         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
 803         if (as_system != NULL) {
 804                 as_system->critical = 0;
 805         }
 806
 807         if (dsdb_module_am_system(module) || as_system) {
 808                 return ldb_next_request(module, req);
 809         }
 810
 811         ldb = ldb_module_get_ctx(module);
 812
 813         parent = ldb_dn_get_parent(req, req->op.add.message->dn);
 814         if (parent == NULL) {
 815                 return ldb_oom(ldb);
 816         }
 817
 818         /* Creating an NC. There is probably something we should do here,
 819          * but we will establish that later */
 820
 821         ret = dsdb_find_nc_root(ldb, req, req->op.add.message->dn, &nc_root);
 822         if (ret != LDB_SUCCESS) {
 823                 return ret;
 824         }
 825         if (ldb_dn_compare(nc_root, req->op.add.message->dn) == 0) {
 826                 talloc_free(nc_root);
 827                 return ldb_next_request(module, req);
 828         }
 829         talloc_free(nc_root);
 830
 831         schema = dsdb_get_schema(ldb, req);
 832         if (!schema) {
 833                 return ldb_operr(ldb);
 834         }
 835
 836         objectclass = dsdb_get_structural_oc_from_msg(schema, req->op.add.message);
 837         if (!objectclass) {
 838                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
 839                                        "acl: unable to find or validate structrual objectClass on %s\n",
 840                                        ldb_dn_get_linearized(req->op.add.message->dn));
 841                 return ldb_module_done(req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR);
 842         }
 843
 844         ret = dsdb_module_check_access_on_dn(module, req, parent,
 845                                              SEC_ADS_CREATE_CHILD,
 846                                              &objectclass->schemaIDGUID, req);
 847         if (ret != LDB_SUCCESS) {
 848                 return ret;
 849         }
 850         return ldb_next_request(module, req);
 851 }
 852
 853 /* ckecks if modifications are allowed on "Member" attribute */
 854 static int acl_check_self_membership(TALLOC_CTX *mem_ctx,
 855                                      struct ldb_module *module,
 856                                      struct ldb_request *req,
 857                                      struct security_descriptor *sd,
 858                                      struct dom_sid *sid,
 859                                      const struct dsdb_attribute *attr,
 860                                      const struct dsdb_class *objectclass)
 861 {
 862         int ret;
 863         unsigned int i;
 864         struct ldb_context *ldb = ldb_module_get_ctx(module);
 865         struct ldb_dn *user_dn;
 866         struct ldb_message_element *member_el;
 867         /* if we have wp, we can do whatever we like */
 868         if (acl_check_access_on_attribute(module,
 869                                           mem_ctx,
 870                                           sd,
 871                                           sid,
 872                                           SEC_ADS_WRITE_PROP,
 873                                           attr, objectclass) == LDB_SUCCESS) {
 874                 return LDB_SUCCESS;
 875         }
 876         /* if we are adding/deleting ourselves, check for self membership */
 877         ret = dsdb_find_dn_by_sid(ldb, mem_ctx,
 878                                   &acl_user_token(module)->sids[PRIMARY_USER_SID_INDEX],
 879                                   &user_dn);
 880         if (ret != LDB_SUCCESS) {
 881                 return ret;
 882         }
 883         member_el = ldb_msg_find_element(req->op.mod.message, "member");
 884         if (!member_el) {
 885                 return ldb_operr(ldb);
 886         }
 887         /* user can only remove oneself */
 888         if (member_el->num_values == 0) {
 889                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 890         }
 891         for (i = 0; i < member_el->num_values; i++) {
 892                 if (strcasecmp((const char *)member_el->values[i].data,
 893                                ldb_dn_get_extended_linearized(mem_ctx, user_dn, 1)) != 0) {
 894                         return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 895                 }
 896         }
 897         ret = acl_check_extended_right(mem_ctx, sd, acl_user_token(module),
 898                                        GUID_DRS_SELF_MEMBERSHIP,
 899                                        SEC_ADS_SELF_WRITE,
 900                                        sid);
 901         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 902                 dsdb_acl_debug(sd, acl_user_token(module),
 903                                req->op.mod.message->dn,
 904                                true,
 905                                10);
 906         }
 907         return ret;
 908 }
 909
 910 static int acl_check_password_rights(TALLOC_CTX *mem_ctx,
 911                                      struct ldb_module *module,
 912                                      struct ldb_request *req,
 913                                      struct security_descriptor *sd,
 914                                      struct dom_sid *sid,
 915                                      const struct dsdb_class *objectclass,
 916                                      bool userPassword)
 917 {
 918         int ret = LDB_SUCCESS;
 919         unsigned int del_attr_cnt = 0, add_attr_cnt = 0, rep_attr_cnt = 0;
 920         struct ldb_message_element *el;
 921         struct ldb_message *msg;
 922         const char *passwordAttrs[] = { "userPassword", "clearTextPassword",
 923                                         "unicodePwd", "dBCSPwd", NULL }, **l;
 924         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 925
 926         msg = ldb_msg_copy_shallow(tmp_ctx, req->op.mod.message);
 927         if (msg == NULL) {
 928                 return ldb_module_oom(module);
 929         }
 930         for (l = passwordAttrs; *l != NULL; l++) {
 931                 if ((!userPassword) && (ldb_attr_cmp(*l, "userPassword") == 0)) {
 932                         continue;
 933                 }
 934
 935                 while ((el = ldb_msg_find_element(msg, *l)) != NULL) {
 936                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_DELETE) {
 937                                 ++del_attr_cnt;
 938                         }
 939                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_ADD) {
 940                                 ++add_attr_cnt;
 941                         }
 942                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_REPLACE) {
 943                                 ++rep_attr_cnt;
 944                         }
 945                         ldb_msg_remove_element(msg, el);
 946                 }
 947         }
 948
 949         /* single deletes will be handled by the "password_hash" LDB module
 950          * later in the stack, so we let it though here */
 951         if ((del_attr_cnt > 0) && (add_attr_cnt == 0) && (rep_attr_cnt == 0)) {
 952                 talloc_free(tmp_ctx);
 953                 return LDB_SUCCESS;
 954         }
 955
 956         if (ldb_request_get_control(req,
 957                                     DSDB_CONTROL_PASSWORD_CHANGE_OID) != NULL) {
 958                 /* The "DSDB_CONTROL_PASSWORD_CHANGE_OID" control means that we
 959                  * have a user password change and not a set as the message
 960                  * looks like. In it's value blob it contains the NT and/or LM
 961                  * hash of the old password specified by the user.
 962                  * This control is used by the SAMR and "kpasswd" password
 963                  * change mechanisms. */
 964                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 965                                                GUID_DRS_USER_CHANGE_PASSWORD,
 966                                                SEC_ADS_CONTROL_ACCESS,
 967                                                sid);
 968         }
 969         else if (rep_attr_cnt > 0 || (add_attr_cnt != del_attr_cnt)) {
 970                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 971                                                GUID_DRS_FORCE_CHANGE_PASSWORD,
 972                                                SEC_ADS_CONTROL_ACCESS,
 973                                                sid);
 974         }
 975         else if (add_attr_cnt == 1 && del_attr_cnt == 1) {
 976                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 977                                                GUID_DRS_USER_CHANGE_PASSWORD,
 978                                                SEC_ADS_CONTROL_ACCESS,
 979                                                sid);
 980                 /* Very strange, but we get constraint violation in this case */
 981                 if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 982                         ret = LDB_ERR_CONSTRAINT_VIOLATION;
 983                 }
 984         }
 985         if (ret != LDB_SUCCESS) {
 986                 dsdb_acl_debug(sd, acl_user_token(module),
 987                                req->op.mod.message->dn,
 988                                true,
 989                                10);
 990         }
 991         talloc_free(tmp_ctx);
 992         return ret;
 993 }
 994
 995
 996 static int acl_modify(struct ldb_module *module, struct ldb_request *req)
 997 {
 998         int ret;
 999         struct ldb_context *ldb = ldb_module_get_ctx(module);
1000         const struct dsdb_schema *schema;
1001         unsigned int i;
1002         const struct dsdb_class *objectclass;
1003         uint32_t access_granted;
1004         NTSTATUS status;
1005         struct ldb_result *acl_res;
1006         struct security_descriptor *sd;
1007         struct dom_sid *sid = NULL;
1008         struct ldb_control *as_system;
1009         bool userPassword;
1010         TALLOC_CTX *tmp_ctx;
1011         const struct ldb_message *msg = req->op.mod.message;
1012         static const char *acl_attrs[] = {
1013                 "nTSecurityDescriptor",
1014                 "objectClass",
1015                 "objectSid",
1016                 NULL
1017         };
1018
1019         if (ldb_dn_is_special(msg->dn)) {
1020                 return ldb_next_request(module, req);
1021         }
1022
1023         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1024         if (as_system != NULL) {
1025                 as_system->critical = 0;
1026         }
1027
1028         /* Don't print this debug statement if elements[0].name is going to be NULL */
1029         if (msg->num_elements > 0) {
1030                 DEBUG(10, ("ldb:acl_modify: %s\n", msg->elements[0].name));
1031         }
1032         if (dsdb_module_am_system(module) || as_system) {
1033                 return ldb_next_request(module, req);
1034         }
1035
1036         tmp_ctx = talloc_new(req);
1037         if (tmp_ctx == NULL) {
1038                 return ldb_oom(ldb);
1039         }
1040
1041         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res, msg->dn,
1042                                     acl_attrs,
1043                                     DSDB_FLAG_NEXT_MODULE |
1044                                     DSDB_FLAG_AS_SYSTEM |
1045                                     DSDB_SEARCH_SHOW_RECYCLED,
1046                                     req);
1047
1048         if (ret != LDB_SUCCESS) {
1049                 goto fail;
1050         }
1051
1052         userPassword = dsdb_user_password_support(module, req, req);
1053
1054         schema = dsdb_get_schema(ldb, tmp_ctx);
1055         if (!schema) {
1056                 talloc_free(tmp_ctx);
1057                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1058                                  "acl_modify: Error obtaining schema.");
1059         }
1060
1061         ret = dsdb_get_sd_from_ldb_message(ldb, tmp_ctx, acl_res->msgs[0], &sd);
1062         if (ret != LDB_SUCCESS) {
1063                 talloc_free(tmp_ctx);
1064                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1065                                  "acl_modify: Error retrieving security descriptor.");
1066         }
1067         /* Theoretically we pass the check if the object has no sd */
1068         if (!sd) {
1069                 goto success;
1070         }
1071
1072         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1073         if (!objectclass) {
1074                 talloc_free(tmp_ctx);
1075                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1076                                  "acl_modify: Error retrieving object class for GUID.");
1077         }
1078         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1079         for (i=0; i < msg->num_elements; i++) {
1080                 const struct ldb_message_element *el = &msg->elements[i];
1081                 const struct dsdb_attribute *attr;
1082
1083                 /*
1084                  * This basic attribute existence check with the right errorcode
1085                  * is needed since this module is the first one which requests
1086                  * schema attribute information.
1087                  * The complete attribute checking is done in the
1088                  * "objectclass_attrs" module behind this one.
1089                  *
1090                  * NOTE: "clearTextPassword" is not defined in the schema.
1091                  */
1092                 attr = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
1093                 if (!attr && ldb_attr_cmp("clearTextPassword", el->name) != 0) {
1094                         ldb_asprintf_errstring(ldb, "acl_modify: attribute '%s' "
1095                                                "on entry '%s' was not found in the schema!",
1096                                                req->op.mod.message->elements[i].name,
1097                                        ldb_dn_get_linearized(req->op.mod.message->dn));
1098                         ret =  LDB_ERR_NO_SUCH_ATTRIBUTE;
1099                         goto fail;
1100                 }
1101
1102                 if (ldb_attr_cmp("nTSecurityDescriptor", el->name) == 0) {
1103                         uint32_t sd_flags = dsdb_request_sd_flags(req, NULL);
1104                         uint32_t access_mask = 0;
1105
1106                         if (sd_flags & (SECINFO_OWNER|SECINFO_GROUP)) {
1107                                 access_mask |= SEC_STD_WRITE_OWNER;
1108                         }
1109                         if (sd_flags & SECINFO_DACL) {
1110                                 access_mask |= SEC_STD_WRITE_DAC;
1111                         }
1112                         if (sd_flags & SECINFO_SACL) {
1113                                 access_mask |= SEC_FLAG_SYSTEM_SECURITY;
1114                         }
1115
1116                         status = sec_access_check_ds(sd, acl_user_token(module),
1117                                              access_mask,
1118                                              &access_granted,
1119                                              NULL,
1120                                              sid);
1121
1122                         if (!NT_STATUS_IS_OK(status)) {
1123                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1124                                                        "Object %s has no write dacl access\n",
1125                                                        ldb_dn_get_linearized(msg->dn));
1126                                 dsdb_acl_debug(sd,
1127                                                acl_user_token(module),
1128                                                msg->dn,
1129                                                true,
1130                                                10);
1131                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1132                                 goto fail;
1133                         }
1134                 } else if (ldb_attr_cmp("member", el->name) == 0) {
1135                         ret = acl_check_self_membership(tmp_ctx,
1136                                                         module,
1137                                                         req,
1138                                                         sd,
1139                                                         sid,
1140                                                         attr,
1141                                                         objectclass);
1142                         if (ret != LDB_SUCCESS) {
1143                                 goto fail;
1144                         }
1145                 } else if (ldb_attr_cmp("dBCSPwd", el->name) == 0) {
1146                         /* this one is not affected by any rights, we should let it through
1147                            so that passwords_hash returns the correct error */
1148                         continue;
1149                 } else if (ldb_attr_cmp("unicodePwd", el->name) == 0 ||
1150                            (userPassword && ldb_attr_cmp("userPassword", el->name) == 0) ||
1151                            ldb_attr_cmp("clearTextPassword", el->name) == 0) {
1152                         ret = acl_check_password_rights(tmp_ctx,
1153                                                         module,
1154                                                         req,
1155                                                         sd,
1156                                                         sid,
1157                                                         objectclass,
1158                                                         userPassword);
1159                         if (ret != LDB_SUCCESS) {
1160                                 goto fail;
1161                         }
1162                 } else if (ldb_attr_cmp("servicePrincipalName", el->name) == 0) {
1163                         ret = acl_check_spn(tmp_ctx,
1164                                             module,
1165                                             req,
1166                                             sd,
1167                                             sid,
1168                                             attr,
1169                                             objectclass);
1170                         if (ret != LDB_SUCCESS) {
1171                                 goto fail;
1172                         }
1173                 } else {
1174                         struct object_tree *root = NULL;
1175                         struct object_tree *new_node = NULL;
1176
1177                         if (!insert_in_object_tree(tmp_ctx,
1178                                                    &objectclass->schemaIDGUID,
1179                                                    SEC_ADS_WRITE_PROP,
1180                                                    &root, &new_node)) {
1181                                 talloc_free(tmp_ctx);
1182                                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1183                                                  "acl_modify: Error adding new node in object tree.");
1184                         }
1185
1186                         if (!insert_in_object_tree(tmp_ctx,
1187                                                    &attr->attributeSecurityGUID, SEC_ADS_WRITE_PROP,
1188                                                    &new_node, &new_node)) {
1189                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1190                                                        "acl_modify: cannot add to object tree securityGUID\n");
1191                                 ret = LDB_ERR_OPERATIONS_ERROR;
1192                                 goto fail;
1193                         }
1194
1195                         if (!insert_in_object_tree(tmp_ctx,
1196                                                    &attr->schemaIDGUID, SEC_ADS_WRITE_PROP, &new_node, &new_node)) {
1197                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1198                                                        "acl_modify: cannot add to object tree attributeGUID\n");
1199                                 ret = LDB_ERR_OPERATIONS_ERROR;
1200                                 goto fail;
1201                         }
1202
1203                         status = sec_access_check_ds(sd, acl_user_token(module),
1204                                                      SEC_ADS_WRITE_PROP,
1205                                                      &access_granted,
1206                                                      root,
1207                                                      sid);
1208                         if (!NT_STATUS_IS_OK(status)) {
1209                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1210                                                        "Object %s has no write property access\n",
1211                                                        ldb_dn_get_linearized(msg->dn));
1212                                 dsdb_acl_debug(sd,
1213                                                acl_user_token(module),
1214                                                msg->dn,
1215                                                true,
1216                                                10);
1217                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1218                                 goto fail;
1219                         }
1220                 }
1221         }
1222
1223 success:
1224         talloc_free(tmp_ctx);
1225         return ldb_next_request(module, req);
1226 fail:
1227         talloc_free(tmp_ctx);
1228         return ret;
1229 }
1230
1231 /* similar to the modify for the time being.
1232  * We need to consider the special delete tree case, though - TODO */
1233 static int acl_delete(struct ldb_module *module, struct ldb_request *req)
1234 {
1235         int ret;
1236         struct ldb_dn *parent;
1237         struct ldb_context *ldb;
1238         struct ldb_dn *nc_root;
1239         struct ldb_control *as_system;
1240
1241         if (ldb_dn_is_special(req->op.del.dn)) {
1242                 return ldb_next_request(module, req);
1243         }
1244
1245         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1246         if (as_system != NULL) {
1247                 as_system->critical = 0;
1248         }
1249
1250         if (dsdb_module_am_system(module) || as_system) {
1251                 return ldb_next_request(module, req);
1252         }
1253
1254         DEBUG(10, ("ldb:acl_delete: %s\n", ldb_dn_get_linearized(req->op.del.dn)));
1255
1256         ldb = ldb_module_get_ctx(module);
1257
1258         parent = ldb_dn_get_parent(req, req->op.del.dn);
1259         if (parent == NULL) {
1260                 return ldb_oom(ldb);
1261         }
1262
1263         /* Make sure we aren't deleting a NC */
1264
1265         ret = dsdb_find_nc_root(ldb, req, req->op.del.dn, &nc_root);
1266         if (ret != LDB_SUCCESS) {
1267                 return ret;
1268         }
1269         if (ldb_dn_compare(nc_root, req->op.del.dn) == 0) {
1270                 talloc_free(nc_root);
1271                 DEBUG(10,("acl:deleting a NC\n"));
1272                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1273                 return ldb_module_done(req, NULL, NULL,
1274                                        LDB_ERR_UNWILLING_TO_PERFORM);
1275         }
1276         talloc_free(nc_root);
1277
1278         if (ldb_request_get_control(req, LDB_CONTROL_TREE_DELETE_OID)) {
1279                 ret = dsdb_module_check_access_on_dn(module, req,
1280                                                      req->op.del.dn,
1281                                                      SEC_ADS_DELETE_TREE, NULL,
1282                                                      req);
1283                 if (ret != LDB_SUCCESS) {
1284                         return ret;
1285                 }
1286
1287                 return ldb_next_request(module, req);
1288         }
1289
1290         /* First check if we have delete object right */
1291         ret = dsdb_module_check_access_on_dn(module, req, req->op.del.dn,
1292                                              SEC_STD_DELETE, NULL, req);
1293         if (ret == LDB_SUCCESS) {
1294                 return ldb_next_request(module, req);
1295         }
1296
1297         /* Nope, we don't have delete object. Lets check if we have delete
1298          * child on the parent */
1299         ret = dsdb_module_check_access_on_dn(module, req, parent,
1300                                              SEC_ADS_DELETE_CHILD, NULL, req);
1301         if (ret != LDB_SUCCESS) {
1302                 return ret;
1303         }
1304
1305         return ldb_next_request(module, req);
1306 }
1307
1308 static int acl_rename(struct ldb_module *module, struct ldb_request *req)
1309 {
1310         int ret;
1311         struct ldb_dn *oldparent;
1312         struct ldb_dn *newparent;
1313         const struct dsdb_schema *schema;
1314         const struct dsdb_class *objectclass;
1315         struct ldb_context *ldb;
1316         struct security_descriptor *sd = NULL;
1317         struct dom_sid *sid = NULL;
1318         struct ldb_result *acl_res;
1319         const struct GUID *guid;
1320         struct ldb_dn *nc_root;
1321         struct object_tree *root = NULL;
1322         struct object_tree *new_node = NULL;
1323         struct ldb_control *as_system;
1324         TALLOC_CTX *tmp_ctx;
1325         NTSTATUS status;
1326         uint32_t access_granted;
1327         const char *rdn_name;
1328         static const char *acl_attrs[] = {
1329                 "nTSecurityDescriptor",
1330                 "objectClass",
1331                 "objectSid",
1332                 NULL
1333         };
1334
1335         if (ldb_dn_is_special(req->op.rename.olddn)) {
1336                 return ldb_next_request(module, req);
1337         }
1338
1339         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1340         if (as_system != NULL) {
1341                 as_system->critical = 0;
1342         }
1343
1344         DEBUG(10, ("ldb:acl_rename: %s\n", ldb_dn_get_linearized(req->op.rename.olddn)));
1345         if (dsdb_module_am_system(module) || as_system) {
1346                 return ldb_next_request(module, req);
1347         }
1348
1349         ldb = ldb_module_get_ctx(module);
1350
1351         tmp_ctx = talloc_new(req);
1352         if (tmp_ctx == NULL) {
1353                 return ldb_oom(ldb);
1354         }
1355
1356         oldparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.olddn);
1357         if (oldparent == NULL) {
1358                 return ldb_oom(ldb);
1359         }
1360         newparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.newdn);
1361         if (newparent == NULL) {
1362                 return ldb_oom(ldb);
1363         }
1364
1365         /* Make sure we aren't renaming/moving a NC */
1366
1367         ret = dsdb_find_nc_root(ldb, req, req->op.rename.olddn, &nc_root);
1368         if (ret != LDB_SUCCESS) {
1369                 return ret;
1370         }
1371         if (ldb_dn_compare(nc_root, req->op.rename.olddn) == 0) {
1372                 talloc_free(nc_root);
1373                 DEBUG(10,("acl:renaming/moving a NC\n"));
1374                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1375                 return ldb_module_done(req, NULL, NULL,
1376                                        LDB_ERR_UNWILLING_TO_PERFORM);
1377         }
1378         talloc_free(nc_root);
1379
1380         /* Look for the parent */
1381
1382         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res,
1383                                     req->op.rename.olddn, acl_attrs,
1384                                     DSDB_FLAG_NEXT_MODULE |
1385                                     DSDB_FLAG_AS_SYSTEM |
1386                                     DSDB_SEARCH_SHOW_RECYCLED, req);
1387         /* we sould be able to find the parent */
1388         if (ret != LDB_SUCCESS) {
1389                 DEBUG(10,("acl: failed to find object %s\n",
1390                           ldb_dn_get_linearized(req->op.rename.olddn)));
1391                 talloc_free(tmp_ctx);
1392                 return ret;
1393         }
1394
1395         schema = dsdb_get_schema(ldb, acl_res);
1396         if (!schema) {
1397                 talloc_free(tmp_ctx);
1398                 return ldb_operr(ldb);
1399         }
1400
1401         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1402         if (!objectclass) {
1403                 talloc_free(tmp_ctx);
1404                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1405                                  "acl_modify: Error retrieving object class for GUID.");
1406         }
1407
1408         if (!insert_in_object_tree(tmp_ctx, &objectclass->schemaIDGUID, SEC_ADS_WRITE_PROP,
1409                                    &root, &new_node)) {
1410                 talloc_free(tmp_ctx);
1411                 return ldb_operr(ldb);
1412         }
1413
1414         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1415                                                           "name");
1416         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1417                                    &new_node, &new_node)) {
1418                 talloc_free(tmp_ctx);
1419                 return ldb_operr(ldb);
1420         }
1421
1422         rdn_name = ldb_dn_get_rdn_name(req->op.rename.olddn);
1423         if (rdn_name == NULL) {
1424                 talloc_free(tmp_ctx);
1425                 return ldb_operr(ldb);
1426         }
1427         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1428                                                           rdn_name);
1429         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1430                                    &new_node, &new_node)) {
1431                 talloc_free(tmp_ctx);
1432                 return ldb_operr(ldb);
1433         };
1434
1435         ret = dsdb_get_sd_from_ldb_message(ldb, req, acl_res->msgs[0], &sd);
1436
1437         if (ret != LDB_SUCCESS) {
1438                 talloc_free(tmp_ctx);
1439                 return ldb_operr(ldb);
1440         }
1441         /* Theoretically we pass the check if the object has no sd */
1442         if (!sd) {
1443                 talloc_free(tmp_ctx);
1444                 return LDB_SUCCESS;
1445         }
1446         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1447         status = sec_access_check_ds(sd, acl_user_token(module),
1448                                      SEC_ADS_WRITE_PROP,
1449                                      &access_granted,
1450                                      root,
1451                                      sid);
1452
1453         if (!NT_STATUS_IS_OK(status)) {
1454                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1455                                        "Object %s has no wp on name\n",
1456                                        ldb_dn_get_linearized(req->op.rename.olddn));
1457                 dsdb_acl_debug(sd,
1458                           acl_user_token(module),
1459                           req->op.rename.olddn,
1460                           true,
1461                           10);
1462                 talloc_free(tmp_ctx);
1463                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1464         }
1465
1466         if (ldb_dn_compare(oldparent, newparent) == 0) {
1467                 /* regular rename, not move, nothing more to do */
1468                 talloc_free(tmp_ctx);
1469                 return ldb_next_request(module, req);
1470         }
1471
1472         /* new parent should have create child */
1473         root = NULL;
1474         new_node = NULL;
1475
1476         ret = dsdb_module_check_access_on_dn(module, req, newparent,
1477                                              SEC_ADS_CREATE_CHILD,
1478                                              &objectclass->schemaIDGUID, req);
1479         if (ret != LDB_SUCCESS) {
1480                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1481                                        "acl:access_denied renaming %s",
1482                                        ldb_dn_get_linearized(req->op.rename.olddn));
1483                 talloc_free(tmp_ctx);
1484                 return ret;
1485         }
1486         /* do we have delete object on the object? */
1487
1488         status = sec_access_check_ds(sd, acl_user_token(module),
1489                                      SEC_STD_DELETE,
1490                                      &access_granted,
1491                                      NULL,
1492                                      sid);
1493
1494         if (NT_STATUS_IS_OK(status)) {
1495                 talloc_free(tmp_ctx);
1496                 return ldb_next_request(module, req);
1497         }
1498         /* what about delete child on the current parent */
1499         ret = dsdb_module_check_access_on_dn(module, req, oldparent, SEC_ADS_DELETE_CHILD, NULL, req);
1500         if (ret != LDB_SUCCESS) {
1501                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1502                                        "acl:access_denied renaming %s", ldb_dn_get_linearized(req->op.rename.olddn));
1503                 talloc_free(tmp_ctx);
1504                 return ldb_module_done(req, NULL, NULL, ret);
1505         }
1506
1507         talloc_free(tmp_ctx);
1508
1509         return ldb_next_request(module, req);
1510 }
1511
1512 static int acl_search_update_confidential_attrs(struct acl_context *ac,
1513                                                 struct acl_private *data)
1514 {
1515         struct dsdb_attribute *a;
1516         uint32_t n = 0;
1517
1518         if (data->acl_search) {
1519                 /*
1520                  * If acl:search is activated, the acl_read module
1521                  * protects confidential attributes.
1522                  */
1523                 return LDB_SUCCESS;
1524         }
1525
1526         if ((ac->schema == data->cached_schema_ptr) &&
1527             (ac->schema->loaded_usn == data->cached_schema_loaded_usn) &&
1528             (ac->schema->metadata_usn == data->cached_schema_metadata_usn))
1529         {
1530                 return LDB_SUCCESS;
1531         }
1532
1533         data->cached_schema_ptr = NULL;
1534         data->cached_schema_loaded_usn = 0;
1535         data->cached_schema_metadata_usn = 0;
1536         TALLOC_FREE(data->confidential_attrs);
1537
1538         if (ac->schema == NULL) {
1539                 return LDB_SUCCESS;
1540         }
1541
1542         for (a = ac->schema->attributes; a; a = a->next) {
1543                 const char **attrs = data->confidential_attrs;
1544
1545                 if (!(a->searchFlags & SEARCH_FLAG_CONFIDENTIAL)) {
1546                         continue;
1547                 }
1548
1549                 attrs = talloc_realloc(data, attrs, const char *, n + 2);
1550                 if (attrs == NULL) {
1551                         TALLOC_FREE(data->confidential_attrs);
1552                         return ldb_module_oom(ac->module);
1553                 }
1554
1555                 attrs[n] = a->lDAPDisplayName;
1556                 attrs[n+1] = NULL;
1557                 n++;
1558
1559                 data->confidential_attrs = attrs;
1560         }
1561
1562         data->cached_schema_ptr = ac->schema;
1563         data->cached_schema_loaded_usn = ac->schema->loaded_usn;
1564         data->cached_schema_metadata_usn = ac->schema->metadata_usn;
1565
1566         return LDB_SUCCESS;
1567 }
1568
1569 static int acl_search_callback(struct ldb_request *req, struct ldb_reply *ares)
1570 {
1571         struct acl_context *ac;
1572         struct acl_private *data;
1573         struct ldb_result *acl_res;
1574         static const char *acl_attrs[] = {
1575                 "objectClass",
1576                 "nTSecurityDescriptor",
1577                 "objectSid",
1578                 NULL
1579         };
1580         int ret;
1581         unsigned int i;
1582
1583         ac = talloc_get_type(req->context, struct acl_context);
1584         data = talloc_get_type(ldb_module_get_private(ac->module), struct acl_private);
1585         if (!ares) {
1586                 return ldb_module_done(ac->req, NULL, NULL,
1587                                        LDB_ERR_OPERATIONS_ERROR);
1588         }
1589         if (ares->error != LDB_SUCCESS) {
1590                 return ldb_module_done(ac->req, ares->controls,
1591                                        ares->response, ares->error);
1592         }
1593
1594         switch (ares->type) {
1595         case LDB_REPLY_ENTRY:
1596                 if (ac->constructed_attrs) {
1597                         ret = dsdb_module_search_dn(ac->module, ac, &acl_res, ares->message->dn,
1598                                                     acl_attrs,
1599                                                     DSDB_FLAG_NEXT_MODULE |
1600                                                     DSDB_FLAG_AS_SYSTEM |
1601                                                     DSDB_SEARCH_SHOW_RECYCLED,
1602                                                     req);
1603                         if (ret != LDB_SUCCESS) {
1604                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1605                         }
1606                 }
1607
1608                 if (ac->allowedAttributes || ac->allowedAttributesEffective) {
1609                         ret = acl_allowedAttributes(ac->module, ac->schema,
1610                                                     acl_res->msgs[0],
1611                                                     ares->message, ac);
1612                         if (ret != LDB_SUCCESS) {
1613                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1614                         }
1615                 }
1616
1617                 if (ac->allowedChildClasses) {
1618                         ret = acl_childClasses(ac->module, ac->schema,
1619                                                acl_res->msgs[0],
1620                                                ares->message,
1621                                                "allowedChildClasses");
1622                         if (ret != LDB_SUCCESS) {
1623                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1624                         }
1625                 }
1626
1627                 if (ac->allowedChildClassesEffective) {
1628                         ret = acl_childClassesEffective(ac->module, ac->schema,
1629                                                         acl_res->msgs[0],
1630                                                         ares->message, ac);
1631                         if (ret != LDB_SUCCESS) {
1632                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1633                         }
1634                 }
1635
1636                 if (ac->sDRightsEffective) {
1637                         ret = acl_sDRightsEffective(ac->module,
1638                                                     acl_res->msgs[0],
1639                                                     ares->message, ac);
1640                         if (ret != LDB_SUCCESS) {
1641                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1642                         }
1643                 }
1644
1645                 if (data == NULL) {
1646                         return ldb_module_send_entry(ac->req, ares->message,
1647                                                      ares->controls);
1648                 }
1649
1650                 if (ac->am_system) {
1651                         return ldb_module_send_entry(ac->req, ares->message,
1652                                                      ares->controls);
1653                 }
1654
1655                 if (data->password_attrs != NULL) {
1656                         for (i = 0; data->password_attrs[i]; i++) {
1657                                 if ((!ac->userPassword) &&
1658                                     (ldb_attr_cmp(data->password_attrs[i],
1659                                                   "userPassword") == 0))
1660                                 {
1661                                                 continue;
1662                                 }
1663
1664                                 ldb_msg_remove_attr(ares->message, data->password_attrs[i]);
1665                         }
1666                 }
1667
1668                 if (ac->am_administrator) {
1669                         return ldb_module_send_entry(ac->req, ares->message,
1670                                                      ares->controls);
1671                 }
1672
1673                 ret = acl_search_update_confidential_attrs(ac, data);
1674                 if (ret != LDB_SUCCESS) {
1675                         return ret;
1676                 }
1677
1678                 if (data->confidential_attrs != NULL) {
1679                         for (i = 0; data->confidential_attrs[i]; i++) {
1680                                 ldb_msg_remove_attr(ares->message,
1681                                                     data->confidential_attrs[i]);
1682                         }
1683                 }
1684
1685                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
1686
1687         case LDB_REPLY_REFERRAL:
1688                 return ldb_module_send_referral(ac->req, ares->referral);
1689
1690         case LDB_REPLY_DONE:
1691                 return ldb_module_done(ac->req, ares->controls,
1692                                        ares->response, LDB_SUCCESS);
1693
1694         }
1695         return LDB_SUCCESS;
1696 }
1697
1698 static int acl_search(struct ldb_module *module, struct ldb_request *req)
1699 {
1700         struct ldb_context *ldb;
1701         struct acl_context *ac;
1702         struct ldb_parse_tree *down_tree;
1703         struct ldb_request *down_req;
1704         struct acl_private *data;
1705         int ret;
1706         unsigned int i;
1707
1708         if (ldb_dn_is_special(req->op.search.base)) {
1709                 return ldb_next_request(module, req);
1710         }
1711
1712         ldb = ldb_module_get_ctx(module);
1713
1714         ac = talloc_zero(req, struct acl_context);
1715         if (ac == NULL) {
1716                 return ldb_oom(ldb);
1717         }
1718         data = talloc_get_type(ldb_module_get_private(module), struct acl_private);
1719
1720         ac->module = module;
1721         ac->req = req;
1722         ac->am_system = dsdb_module_am_system(module);
1723         ac->am_administrator = dsdb_module_am_administrator(module);
1724         ac->constructed_attrs = false;
1725         ac->modify_search = true;
1726         ac->allowedAttributes = ldb_attr_in_list(req->op.search.attrs, "allowedAttributes");
1727         ac->allowedAttributesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedAttributesEffective");
1728         ac->allowedChildClasses = ldb_attr_in_list(req->op.search.attrs, "allowedChildClasses");
1729         ac->allowedChildClassesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedChildClassesEffective");
1730         ac->sDRightsEffective = ldb_attr_in_list(req->op.search.attrs, "sDRightsEffective");
1731         ac->userPassword = true;
1732         ac->schema = dsdb_get_schema(ldb, ac);
1733
1734         ac->constructed_attrs |= ac->allowedAttributes;
1735         ac->constructed_attrs |= ac->allowedChildClasses;
1736         ac->constructed_attrs |= ac->allowedChildClassesEffective;
1737         ac->constructed_attrs |= ac->allowedAttributesEffective;
1738         ac->constructed_attrs |= ac->sDRightsEffective;
1739
1740         if (data == NULL) {
1741                 ac->modify_search = false;
1742         }
1743         if (ac->am_system) {
1744                 ac->modify_search = false;
1745         }
1746
1747         if (!ac->constructed_attrs && !ac->modify_search) {
1748                 talloc_free(ac);
1749                 return ldb_next_request(module, req);
1750         }
1751
1752         if (!ac->am_system) {
1753                 ac->userPassword = dsdb_user_password_support(module, ac, req);
1754         }
1755
1756         ret = acl_search_update_confidential_attrs(ac, data);
1757         if (ret != LDB_SUCCESS) {
1758                 return ret;
1759         }
1760
1761         down_tree = ldb_parse_tree_copy_shallow(ac, req->op.search.tree);
1762         if (down_tree == NULL) {
1763                 return ldb_oom(ldb);
1764         }
1765
1766         if (!ac->am_system && data->password_attrs) {
1767                 for (i = 0; data->password_attrs[i]; i++) {
1768                         if ((!ac->userPassword) &&
1769                             (ldb_attr_cmp(data->password_attrs[i],
1770                                           "userPassword") == 0))
1771                         {
1772                                 continue;
1773                         }
1774
1775                         ldb_parse_tree_attr_replace(down_tree,
1776                                                     data->password_attrs[i],
1777                                                     "kludgeACLredactedattribute");
1778                 }
1779         }
1780
1781         if (!ac->am_system && !ac->am_administrator && data->confidential_attrs) {
1782                 for (i = 0; data->confidential_attrs[i]; i++) {
1783                         ldb_parse_tree_attr_replace(down_tree,
1784                                                     data->confidential_attrs[i],
1785                                                     "kludgeACLredactedattribute");
1786                 }
1787         }
1788
1789         ret = ldb_build_search_req_ex(&down_req,
1790                                       ldb, ac,
1791                                       req->op.search.base,
1792                                       req->op.search.scope,
1793                                       down_tree,
1794                                       req->op.search.attrs,
1795                                       req->controls,
1796                                       ac, acl_search_callback,
1797                                       req);
1798         LDB_REQ_SET_LOCATION(down_req);
1799         if (ret != LDB_SUCCESS) {
1800                 return ret;
1801         }
1802         /* perform the search */
1803         return ldb_next_request(module, down_req);
1804 }
1805
1806 static int acl_extended(struct ldb_module *module, struct ldb_request *req)
1807 {
1808         struct ldb_context *ldb = ldb_module_get_ctx(module);
1809         struct ldb_control *as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1810
1811         /* allow everybody to read the sequence number */
1812         if (strcmp(req->op.extended.oid,
1813                    LDB_EXTENDED_SEQUENCE_NUMBER) == 0) {
1814                 return ldb_next_request(module, req);
1815         }
1816
1817         if (dsdb_module_am_system(module) ||
1818             dsdb_module_am_administrator(module) || as_system) {
1819                 return ldb_next_request(module, req);
1820         } else {
1821                 ldb_asprintf_errstring(ldb,
1822                                        "acl_extended: "
1823                                        "attempted database modify not permitted. "
1824                                        "User %s is not SYSTEM or an administrator",
1825                                        acl_user_name(req, module));
1826                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1827         }
1828 }
1829
1830 static const struct ldb_module_ops ldb_acl_module_ops = {
1831         .name              = "acl",
1832         .search            = acl_search,
1833         .add               = acl_add,
1834         .modify            = acl_modify,
1835         .del               = acl_delete,
1836         .rename            = acl_rename,
1837         .extended          = acl_extended,
1838         .init_context      = acl_module_init
1839 };
1840
1841 int ldb_acl_module_init(const char *version)
1842 {
1843         LDB_MODULE_CHECK_VERSION(version);
1844         return ldb_register_module(&ldb_acl_module_ops);
1845 }