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                         ret = acl_check_access_on_class(module,
 438                                                         schema,
 439                                                         msg,
 440                                                         sd,
 441                                                         acl_user_token(module),
 442                                                         sid,
 443                                                         SEC_ADS_CREATE_CHILD,
 444                                                         sclass->possibleInferiors[j]);
 445                         if (ret == LDB_SUCCESS) {
 446                                 ldb_msg_add_string(msg, "allowedChildClassesEffective",
 447                                                    sclass->possibleInferiors[j]);
 448                         }
 449                 }
 450         }
 451         allowedClasses = ldb_msg_find_element(msg, "allowedChildClassesEffective");
 452         if (!allowedClasses) {
 453                 return LDB_SUCCESS;
 454         }
 455
 456         if (allowedClasses->num_values > 1) {
 457                 TYPESAFE_QSORT(allowedClasses->values, allowedClasses->num_values, data_blob_cmp);
 458                 for (i=1 ; i < allowedClasses->num_values; i++) {
 459                         struct ldb_val *val1 = &allowedClasses->values[i-1];
 460                         struct ldb_val *val2 = &allowedClasses->values[i];
 461                         if (data_blob_cmp(val1, val2) == 0) {
 462                                 memmove(val1, val2, (allowedClasses->num_values - i) * sizeof( struct ldb_val));
 463                                 allowedClasses->num_values--;
 464                                 i--;
 465                         }
 466                 }
 467         }
 468         return LDB_SUCCESS;
 469 }
 470
 471 static int acl_sDRightsEffective(struct ldb_module *module,
 472                                  struct ldb_message *sd_msg,
 473                                  struct ldb_message *msg,
 474                                  struct acl_context *ac)
 475 {
 476         struct ldb_context *ldb = ldb_module_get_ctx(module);
 477         struct ldb_message_element *rightsEffective;
 478         int ret;
 479         struct security_descriptor *sd;
 480         struct ldb_control *as_system = ldb_request_get_control(ac->req,
 481                                                                 LDB_CONTROL_AS_SYSTEM_OID);
 482         struct dom_sid *sid = NULL;
 483         uint32_t flags = 0;
 484
 485         if (as_system != NULL) {
 486                 as_system->critical = 0;
 487         }
 488
 489         /* Must remove any existing attribute, or else confusion reins */
 490         ldb_msg_remove_attr(msg, "sDRightsEffective");
 491         ret = ldb_msg_add_empty(msg, "sDRightsEffective", 0, &rightsEffective);
 492         if (ret != LDB_SUCCESS) {
 493                 return ret;
 494         }
 495         if (ac->am_system || as_system) {
 496                 flags = SECINFO_OWNER | SECINFO_GROUP |  SECINFO_SACL |  SECINFO_DACL;
 497         } else {
 498                 const struct dsdb_class *objectclass;
 499                 const struct dsdb_attribute *attr;
 500
 501                 objectclass = dsdb_get_structural_oc_from_msg(ac->schema, sd_msg);
 502                 if (objectclass == NULL) {
 503                         return ldb_operr(ldb);
 504                 }
 505
 506                 attr = dsdb_attribute_by_lDAPDisplayName(ac->schema,
 507                                                          "nTSecurityDescriptor");
 508                 if (attr == NULL) {
 509                         return ldb_operr(ldb);
 510                 }
 511
 512                 /* Get the security descriptor from the message */
 513                 ret = dsdb_get_sd_from_ldb_message(ldb, msg, sd_msg, &sd);
 514                 if (ret != LDB_SUCCESS) {
 515                         return ret;
 516                 }
 517                 sid = samdb_result_dom_sid(msg, sd_msg, "objectSid");
 518                 ret = acl_check_access_on_attribute(module,
 519                                                     msg,
 520                                                     sd,
 521                                                     sid,
 522                                                     SEC_STD_WRITE_OWNER,
 523                                                     attr,
 524                                                     objectclass);
 525                 if (ret == LDB_SUCCESS) {
 526                         flags |= SECINFO_OWNER | SECINFO_GROUP;
 527                 }
 528                 ret = acl_check_access_on_attribute(module,
 529                                                     msg,
 530                                                     sd,
 531                                                     sid,
 532                                                     SEC_STD_WRITE_DAC,
 533                                                     attr,
 534                                                     objectclass);
 535                 if (ret == LDB_SUCCESS) {
 536                         flags |= SECINFO_DACL;
 537                 }
 538                 ret = acl_check_access_on_attribute(module,
 539                                                     msg,
 540                                                     sd,
 541                                                     sid,
 542                                                     SEC_FLAG_SYSTEM_SECURITY,
 543                                                     attr,
 544                                                     objectclass);
 545                 if (ret == LDB_SUCCESS) {
 546                         flags |= SECINFO_SACL;
 547                 }
 548         }
 549         return samdb_msg_add_uint(ldb_module_get_ctx(module), msg, msg,
 550                                   "sDRightsEffective", flags);
 551 }
 552
 553 static int acl_validate_spn_value(TALLOC_CTX *mem_ctx,
 554                                   struct ldb_context *ldb,
 555                                   const char *spn_value,
 556                                   uint32_t userAccountControl,
 557                                   const char *samAccountName,
 558                                   const char *dnsHostName,
 559                                   const char *netbios_name,
 560                                   const char *ntds_guid)
 561 {
 562         int ret;
 563         krb5_context krb_ctx;
 564         krb5_error_code kerr;
 565         krb5_principal principal;
 566         char *instanceName;
 567         char *serviceType;
 568         char *serviceName;
 569         const char *forest_name = samdb_forest_name(ldb, mem_ctx);
 570         const char *base_domain = samdb_default_domain_name(ldb, mem_ctx);
 571         struct loadparm_context *lp_ctx = talloc_get_type(ldb_get_opaque(ldb, "loadparm"),
 572                                                           struct loadparm_context);
 573         bool is_dc = (userAccountControl & UF_SERVER_TRUST_ACCOUNT) ||
 574                 (userAccountControl & UF_PARTIAL_SECRETS_ACCOUNT);
 575
 576         if (strcasecmp_m(spn_value, samAccountName) == 0) {
 577                 /* MacOS X sets this value, and setting an SPN of your
 578                  * own samAccountName is both pointless and safe */
 579                 return LDB_SUCCESS;
 580         }
 581
 582         kerr = smb_krb5_init_context_basic(mem_ctx,
 583                                            lp_ctx,
 584                                            &krb_ctx);
 585         if (kerr != 0) {
 586                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 587                                  "Could not initialize kerberos context.");
 588         }
 589
 590         ret = krb5_parse_name(krb_ctx, spn_value, &principal);
 591         if (ret) {
 592                 krb5_free_context(krb_ctx);
 593                 return LDB_ERR_CONSTRAINT_VIOLATION;
 594         }
 595
 596         if (principal->name.name_string.len < 2) {
 597                 goto fail;
 598         }
 599
 600         instanceName = principal->name.name_string.val[1];
 601         serviceType = principal->name.name_string.val[0];
 602         if (principal->name.name_string.len == 3) {
 603                 serviceName = principal->name.name_string.val[2];
 604         } else {
 605                 serviceName = NULL;
 606         }
 607
 608         if (serviceName) {
 609                 if (!is_dc) {
 610                         goto fail;
 611                 }
 612                 if (strcasecmp(serviceType, "ldap") == 0) {
 613                         if (strcasecmp(serviceName, netbios_name) != 0 &&
 614                             strcasecmp(serviceName, forest_name) != 0) {
 615                                 goto fail;
 616                         }
 617
 618                 } else if (strcasecmp(serviceType, "gc") == 0) {
 619                         if (strcasecmp(serviceName, forest_name) != 0) {
 620                                 goto fail;
 621                         }
 622                 } else {
 623                         if (strcasecmp(serviceName, base_domain) != 0 &&
 624                             strcasecmp(serviceName, netbios_name) != 0) {
 625                                 goto fail;
 626                         }
 627                 }
 628         }
 629         /* instanceName can be samAccountName without $ or dnsHostName
 630          * or "ntds_guid._msdcs.forest_domain for DC objects */
 631         if (strlen(instanceName) == (strlen(samAccountName) - 1)
 632             && strncasecmp(instanceName, samAccountName, strlen(samAccountName) - 1) == 0) {
 633                 goto success;
 634         } else if (dnsHostName != NULL && strcasecmp(instanceName, dnsHostName) == 0) {
 635                 goto success;
 636         } else if (is_dc) {
 637                 const char *guid_str;
 638                 guid_str = talloc_asprintf(mem_ctx,"%s._msdcs.%s",
 639                                            ntds_guid,
 640                                            forest_name);
 641                 if (strcasecmp(instanceName, guid_str) == 0) {
 642                         goto success;
 643                 }
 644         }
 645
 646 fail:
 647         krb5_free_principal(krb_ctx, principal);
 648         krb5_free_context(krb_ctx);
 649         return LDB_ERR_CONSTRAINT_VIOLATION;
 650
 651 success:
 652         krb5_free_principal(krb_ctx, principal);
 653         krb5_free_context(krb_ctx);
 654         return LDB_SUCCESS;
 655 }
 656
 657 static int acl_check_spn(TALLOC_CTX *mem_ctx,
 658                          struct ldb_module *module,
 659                          struct ldb_request *req,
 660                          struct security_descriptor *sd,
 661                          struct dom_sid *sid,
 662                          const struct dsdb_attribute *attr,
 663                          const struct dsdb_class *objectclass)
 664 {
 665         int ret;
 666         unsigned int i;
 667         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 668         struct ldb_context *ldb = ldb_module_get_ctx(module);
 669         struct ldb_result *acl_res;
 670         struct ldb_result *netbios_res;
 671         struct ldb_message_element *el;
 672         struct ldb_dn *partitions_dn = samdb_partitions_dn(ldb, tmp_ctx);
 673         uint32_t userAccountControl;
 674         const char *samAccountName;
 675         const char *dnsHostName;
 676         const char *netbios_name;
 677         struct GUID ntds;
 678         char *ntds_guid = NULL;
 679
 680         static const char *acl_attrs[] = {
 681                 "samAccountName",
 682                 "dnsHostName",
 683                 "userAccountControl",
 684                 NULL
 685         };
 686         static const char *netbios_attrs[] = {
 687                 "nETBIOSName",
 688                 NULL
 689         };
 690
 691         /* if we have wp, we can do whatever we like */
 692         if (acl_check_access_on_attribute(module,
 693                                           tmp_ctx,
 694                                           sd,
 695                                           sid,
 696                                           SEC_ADS_WRITE_PROP,
 697                                           attr, objectclass) == LDB_SUCCESS) {
 698                 talloc_free(tmp_ctx);
 699                 return LDB_SUCCESS;
 700         }
 701
 702         ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 703                                        GUID_DRS_VALIDATE_SPN,
 704                                        SEC_ADS_SELF_WRITE,
 705                                        sid);
 706
 707         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 708                 dsdb_acl_debug(sd, acl_user_token(module),
 709                                req->op.mod.message->dn,
 710                                true,
 711                                10);
 712                 talloc_free(tmp_ctx);
 713                 return ret;
 714         }
 715
 716         ret = dsdb_module_search_dn(module, tmp_ctx,
 717                                     &acl_res, req->op.mod.message->dn,
 718                                     acl_attrs,
 719                                     DSDB_FLAG_NEXT_MODULE |
 720                                     DSDB_FLAG_AS_SYSTEM |
 721                                     DSDB_SEARCH_SHOW_RECYCLED,
 722                                     req);
 723         if (ret != LDB_SUCCESS) {
 724                 talloc_free(tmp_ctx);
 725                 return ret;
 726         }
 727
 728         userAccountControl = ldb_msg_find_attr_as_uint(acl_res->msgs[0], "userAccountControl", 0);
 729         dnsHostName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "dnsHostName", NULL);
 730         samAccountName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "samAccountName", NULL);
 731
 732         ret = dsdb_module_search(module, tmp_ctx,
 733                                  &netbios_res, partitions_dn,
 734                                  LDB_SCOPE_ONELEVEL,
 735                                  netbios_attrs,
 736                                  DSDB_FLAG_NEXT_MODULE |
 737                                  DSDB_FLAG_AS_SYSTEM,
 738                                  req,
 739                                  "(ncName=%s)",
 740                                  ldb_dn_get_linearized(ldb_get_default_basedn(ldb)));
 741
 742         netbios_name = ldb_msg_find_attr_as_string(netbios_res->msgs[0], "nETBIOSName", NULL);
 743
 744         el = ldb_msg_find_element(req->op.mod.message, "servicePrincipalName");
 745         if (!el) {
 746                 talloc_free(tmp_ctx);
 747                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 748                                          "Error finding element for servicePrincipalName.");
 749         }
 750
 751         /* NTDSDSA objectGuid of object we are checking SPN for */
 752         if (userAccountControl & (UF_SERVER_TRUST_ACCOUNT | UF_PARTIAL_SECRETS_ACCOUNT)) {
 753                 ret = dsdb_module_find_ntdsguid_for_computer(module, tmp_ctx,
 754                                                              req->op.mod.message->dn, &ntds, req);
 755                 if (ret != LDB_SUCCESS) {
 756                         ldb_asprintf_errstring(ldb, "Failed to find NTDSDSA objectGuid for %s: %s",
 757                                                ldb_dn_get_linearized(req->op.mod.message->dn),
 758                                                ldb_strerror(ret));
 759                         talloc_free(tmp_ctx);
 760                         return LDB_ERR_OPERATIONS_ERROR;
 761                 }
 762                 ntds_guid = GUID_string(tmp_ctx, &ntds);
 763         }
 764
 765         for (i=0; i < el->num_values; i++) {
 766                 ret = acl_validate_spn_value(tmp_ctx,
 767                                              ldb,
 768                                              (char *)el->values[i].data,
 769                                              userAccountControl,
 770                                              samAccountName,
 771                                              dnsHostName,
 772                                              netbios_name,
 773                                              ntds_guid);
 774                 if (ret != LDB_SUCCESS) {
 775                         talloc_free(tmp_ctx);
 776                         return ret;
 777                 }
 778         }
 779         talloc_free(tmp_ctx);
 780         return LDB_SUCCESS;
 781 }
 782
 783 static int acl_add(struct ldb_module *module, struct ldb_request *req)
 784 {
 785         int ret;
 786         struct ldb_dn *parent;
 787         struct ldb_context *ldb;
 788         const struct dsdb_schema *schema;
 789         const struct dsdb_class *objectclass;
 790         struct ldb_dn *nc_root;
 791         struct ldb_control *as_system;
 792
 793         if (ldb_dn_is_special(req->op.add.message->dn)) {
 794                 return ldb_next_request(module, req);
 795         }
 796
 797         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
 798         if (as_system != NULL) {
 799                 as_system->critical = 0;
 800         }
 801
 802         if (dsdb_module_am_system(module) || as_system) {
 803                 return ldb_next_request(module, req);
 804         }
 805
 806         ldb = ldb_module_get_ctx(module);
 807
 808         parent = ldb_dn_get_parent(req, req->op.add.message->dn);
 809         if (parent == NULL) {
 810                 return ldb_oom(ldb);
 811         }
 812
 813         /* Creating an NC. There is probably something we should do here,
 814          * but we will establish that later */
 815
 816         ret = dsdb_find_nc_root(ldb, req, req->op.add.message->dn, &nc_root);
 817         if (ret != LDB_SUCCESS) {
 818                 return ret;
 819         }
 820         if (ldb_dn_compare(nc_root, req->op.add.message->dn) == 0) {
 821                 talloc_free(nc_root);
 822                 return ldb_next_request(module, req);
 823         }
 824         talloc_free(nc_root);
 825
 826         schema = dsdb_get_schema(ldb, req);
 827         if (!schema) {
 828                 return ldb_operr(ldb);
 829         }
 830
 831         objectclass = dsdb_get_structural_oc_from_msg(schema, req->op.add.message);
 832         if (!objectclass) {
 833                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
 834                                        "acl: unable to find or validate structrual objectClass on %s\n",
 835                                        ldb_dn_get_linearized(req->op.add.message->dn));
 836                 return ldb_module_done(req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR);
 837         }
 838
 839         ret = dsdb_module_check_access_on_dn(module, req, parent,
 840                                              SEC_ADS_CREATE_CHILD,
 841                                              &objectclass->schemaIDGUID, req);
 842         if (ret != LDB_SUCCESS) {
 843                 return ret;
 844         }
 845         return ldb_next_request(module, req);
 846 }
 847
 848 /* ckecks if modifications are allowed on "Member" attribute */
 849 static int acl_check_self_membership(TALLOC_CTX *mem_ctx,
 850                                      struct ldb_module *module,
 851                                      struct ldb_request *req,
 852                                      struct security_descriptor *sd,
 853                                      struct dom_sid *sid,
 854                                      const struct dsdb_attribute *attr,
 855                                      const struct dsdb_class *objectclass)
 856 {
 857         int ret;
 858         unsigned int i;
 859         struct ldb_context *ldb = ldb_module_get_ctx(module);
 860         struct ldb_dn *user_dn;
 861         struct ldb_message_element *member_el;
 862         /* if we have wp, we can do whatever we like */
 863         if (acl_check_access_on_attribute(module,
 864                                           mem_ctx,
 865                                           sd,
 866                                           sid,
 867                                           SEC_ADS_WRITE_PROP,
 868                                           attr, objectclass) == LDB_SUCCESS) {
 869                 return LDB_SUCCESS;
 870         }
 871         /* if we are adding/deleting ourselves, check for self membership */
 872         ret = dsdb_find_dn_by_sid(ldb, mem_ctx,
 873                                   &acl_user_token(module)->sids[PRIMARY_USER_SID_INDEX],
 874                                   &user_dn);
 875         if (ret != LDB_SUCCESS) {
 876                 return ret;
 877         }
 878         member_el = ldb_msg_find_element(req->op.mod.message, "member");
 879         if (!member_el) {
 880                 return ldb_operr(ldb);
 881         }
 882         /* user can only remove oneself */
 883         if (member_el->num_values == 0) {
 884                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 885         }
 886         for (i = 0; i < member_el->num_values; i++) {
 887                 if (strcasecmp((const char *)member_el->values[i].data,
 888                                ldb_dn_get_extended_linearized(mem_ctx, user_dn, 1)) != 0) {
 889                         return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 890                 }
 891         }
 892         ret = acl_check_extended_right(mem_ctx, sd, acl_user_token(module),
 893                                        GUID_DRS_SELF_MEMBERSHIP,
 894                                        SEC_ADS_SELF_WRITE,
 895                                        sid);
 896         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 897                 dsdb_acl_debug(sd, acl_user_token(module),
 898                                req->op.mod.message->dn,
 899                                true,
 900                                10);
 901         }
 902         return ret;
 903 }
 904
 905 static int acl_check_password_rights(TALLOC_CTX *mem_ctx,
 906                                      struct ldb_module *module,
 907                                      struct ldb_request *req,
 908                                      struct security_descriptor *sd,
 909                                      struct dom_sid *sid,
 910                                      const struct dsdb_class *objectclass,
 911                                      bool userPassword)
 912 {
 913         int ret = LDB_SUCCESS;
 914         unsigned int del_attr_cnt = 0, add_attr_cnt = 0, rep_attr_cnt = 0;
 915         struct ldb_message_element *el;
 916         struct ldb_message *msg;
 917         const char *passwordAttrs[] = { "userPassword", "clearTextPassword",
 918                                         "unicodePwd", "dBCSPwd", NULL }, **l;
 919         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 920
 921         msg = ldb_msg_copy_shallow(tmp_ctx, req->op.mod.message);
 922         if (msg == NULL) {
 923                 return ldb_module_oom(module);
 924         }
 925         for (l = passwordAttrs; *l != NULL; l++) {
 926                 if ((!userPassword) && (ldb_attr_cmp(*l, "userPassword") == 0)) {
 927                         continue;
 928                 }
 929
 930                 while ((el = ldb_msg_find_element(msg, *l)) != NULL) {
 931                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_DELETE) {
 932                                 ++del_attr_cnt;
 933                         }
 934                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_ADD) {
 935                                 ++add_attr_cnt;
 936                         }
 937                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_REPLACE) {
 938                                 ++rep_attr_cnt;
 939                         }
 940                         ldb_msg_remove_element(msg, el);
 941                 }
 942         }
 943
 944         /* single deletes will be handled by the "password_hash" LDB module
 945          * later in the stack, so we let it though here */
 946         if ((del_attr_cnt > 0) && (add_attr_cnt == 0) && (rep_attr_cnt == 0)) {
 947                 talloc_free(tmp_ctx);
 948                 return LDB_SUCCESS;
 949         }
 950
 951         if (ldb_request_get_control(req,
 952                                     DSDB_CONTROL_PASSWORD_CHANGE_OID) != NULL) {
 953                 /* The "DSDB_CONTROL_PASSWORD_CHANGE_OID" control means that we
 954                  * have a user password change and not a set as the message
 955                  * looks like. In it's value blob it contains the NT and/or LM
 956                  * hash of the old password specified by the user.
 957                  * This control is used by the SAMR and "kpasswd" password
 958                  * change mechanisms. */
 959                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 960                                                GUID_DRS_USER_CHANGE_PASSWORD,
 961                                                SEC_ADS_CONTROL_ACCESS,
 962                                                sid);
 963         }
 964         else if (rep_attr_cnt > 0 || (add_attr_cnt != del_attr_cnt)) {
 965                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 966                                                GUID_DRS_FORCE_CHANGE_PASSWORD,
 967                                                SEC_ADS_CONTROL_ACCESS,
 968                                                sid);
 969         }
 970         else if (add_attr_cnt == 1 && del_attr_cnt == 1) {
 971                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 972                                                GUID_DRS_USER_CHANGE_PASSWORD,
 973                                                SEC_ADS_CONTROL_ACCESS,
 974                                                sid);
 975                 /* Very strange, but we get constraint violation in this case */
 976                 if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 977                         ret = LDB_ERR_CONSTRAINT_VIOLATION;
 978                 }
 979         }
 980         if (ret != LDB_SUCCESS) {
 981                 dsdb_acl_debug(sd, acl_user_token(module),
 982                                req->op.mod.message->dn,
 983                                true,
 984                                10);
 985         }
 986         talloc_free(tmp_ctx);
 987         return ret;
 988 }
 989
 990
 991 static int acl_modify(struct ldb_module *module, struct ldb_request *req)
 992 {
 993         int ret;
 994         struct ldb_context *ldb = ldb_module_get_ctx(module);
 995         const struct dsdb_schema *schema;
 996         unsigned int i;
 997         const struct dsdb_class *objectclass;
 998         uint32_t access_granted;
 999         NTSTATUS status;
1000         struct ldb_result *acl_res;
1001         struct security_descriptor *sd;
1002         struct dom_sid *sid = NULL;
1003         struct ldb_control *as_system;
1004         bool userPassword;
1005         TALLOC_CTX *tmp_ctx;
1006         const struct ldb_message *msg = req->op.mod.message;
1007         static const char *acl_attrs[] = {
1008                 "nTSecurityDescriptor",
1009                 "objectClass",
1010                 "objectSid",
1011                 NULL
1012         };
1013
1014         if (ldb_dn_is_special(msg->dn)) {
1015                 return ldb_next_request(module, req);
1016         }
1017
1018         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1019         if (as_system != NULL) {
1020                 as_system->critical = 0;
1021         }
1022
1023         /* Don't print this debug statement if elements[0].name is going to be NULL */
1024         if (msg->num_elements > 0) {
1025                 DEBUG(10, ("ldb:acl_modify: %s\n", msg->elements[0].name));
1026         }
1027         if (dsdb_module_am_system(module) || as_system) {
1028                 return ldb_next_request(module, req);
1029         }
1030
1031         tmp_ctx = talloc_new(req);
1032         if (tmp_ctx == NULL) {
1033                 return ldb_oom(ldb);
1034         }
1035
1036         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res, msg->dn,
1037                                     acl_attrs,
1038                                     DSDB_FLAG_NEXT_MODULE |
1039                                     DSDB_FLAG_AS_SYSTEM |
1040                                     DSDB_SEARCH_SHOW_RECYCLED,
1041                                     req);
1042
1043         if (ret != LDB_SUCCESS) {
1044                 goto fail;
1045         }
1046
1047         userPassword = dsdb_user_password_support(module, req, req);
1048
1049         schema = dsdb_get_schema(ldb, tmp_ctx);
1050         if (!schema) {
1051                 talloc_free(tmp_ctx);
1052                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1053                                  "acl_modify: Error obtaining schema.");
1054         }
1055
1056         ret = dsdb_get_sd_from_ldb_message(ldb, tmp_ctx, acl_res->msgs[0], &sd);
1057         if (ret != LDB_SUCCESS) {
1058                 talloc_free(tmp_ctx);
1059                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1060                                  "acl_modify: Error retrieving security descriptor.");
1061         }
1062         /* Theoretically we pass the check if the object has no sd */
1063         if (!sd) {
1064                 goto success;
1065         }
1066
1067         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1068         if (!objectclass) {
1069                 talloc_free(tmp_ctx);
1070                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1071                                  "acl_modify: Error retrieving object class for GUID.");
1072         }
1073         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1074         for (i=0; i < msg->num_elements; i++) {
1075                 const struct ldb_message_element *el = &msg->elements[i];
1076                 const struct dsdb_attribute *attr;
1077
1078                 /*
1079                  * This basic attribute existence check with the right errorcode
1080                  * is needed since this module is the first one which requests
1081                  * schema attribute information.
1082                  * The complete attribute checking is done in the
1083                  * "objectclass_attrs" module behind this one.
1084                  *
1085                  * NOTE: "clearTextPassword" is not defined in the schema.
1086                  */
1087                 attr = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
1088                 if (!attr && ldb_attr_cmp("clearTextPassword", el->name) != 0) {
1089                         ldb_asprintf_errstring(ldb, "acl_modify: attribute '%s' "
1090                                                "on entry '%s' was not found in the schema!",
1091                                                req->op.mod.message->elements[i].name,
1092                                        ldb_dn_get_linearized(req->op.mod.message->dn));
1093                         ret =  LDB_ERR_NO_SUCH_ATTRIBUTE;
1094                         goto fail;
1095                 }
1096
1097                 if (ldb_attr_cmp("nTSecurityDescriptor", el->name) == 0) {
1098                         uint32_t sd_flags = dsdb_request_sd_flags(req, NULL);
1099                         uint32_t access_mask = 0;
1100
1101                         if (sd_flags & (SECINFO_OWNER|SECINFO_GROUP)) {
1102                                 access_mask |= SEC_STD_WRITE_OWNER;
1103                         }
1104                         if (sd_flags & SECINFO_DACL) {
1105                                 access_mask |= SEC_STD_WRITE_DAC;
1106                         }
1107                         if (sd_flags & SECINFO_SACL) {
1108                                 access_mask |= SEC_FLAG_SYSTEM_SECURITY;
1109                         }
1110
1111                         status = sec_access_check_ds(sd, acl_user_token(module),
1112                                              access_mask,
1113                                              &access_granted,
1114                                              NULL,
1115                                              sid);
1116
1117                         if (!NT_STATUS_IS_OK(status)) {
1118                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1119                                                        "Object %s has no write dacl access\n",
1120                                                        ldb_dn_get_linearized(msg->dn));
1121                                 dsdb_acl_debug(sd,
1122                                                acl_user_token(module),
1123                                                msg->dn,
1124                                                true,
1125                                                10);
1126                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1127                                 goto fail;
1128                         }
1129                 } else if (ldb_attr_cmp("member", el->name) == 0) {
1130                         ret = acl_check_self_membership(tmp_ctx,
1131                                                         module,
1132                                                         req,
1133                                                         sd,
1134                                                         sid,
1135                                                         attr,
1136                                                         objectclass);
1137                         if (ret != LDB_SUCCESS) {
1138                                 goto fail;
1139                         }
1140                 } else if (ldb_attr_cmp("dBCSPwd", el->name) == 0) {
1141                         /* this one is not affected by any rights, we should let it through
1142                            so that passwords_hash returns the correct error */
1143                         continue;
1144                 } else if (ldb_attr_cmp("unicodePwd", el->name) == 0 ||
1145                            (userPassword && ldb_attr_cmp("userPassword", el->name) == 0) ||
1146                            ldb_attr_cmp("clearTextPassword", el->name) == 0) {
1147                         ret = acl_check_password_rights(tmp_ctx,
1148                                                         module,
1149                                                         req,
1150                                                         sd,
1151                                                         sid,
1152                                                         objectclass,
1153                                                         userPassword);
1154                         if (ret != LDB_SUCCESS) {
1155                                 goto fail;
1156                         }
1157                 } else if (ldb_attr_cmp("servicePrincipalName", el->name) == 0) {
1158                         ret = acl_check_spn(tmp_ctx,
1159                                             module,
1160                                             req,
1161                                             sd,
1162                                             sid,
1163                                             attr,
1164                                             objectclass);
1165                         if (ret != LDB_SUCCESS) {
1166                                 goto fail;
1167                         }
1168                 } else {
1169                         struct object_tree *root = NULL;
1170                         struct object_tree *new_node = NULL;
1171
1172                         if (!insert_in_object_tree(tmp_ctx,
1173                                                    &objectclass->schemaIDGUID,
1174                                                    SEC_ADS_WRITE_PROP,
1175                                                    &root, &new_node)) {
1176                                 talloc_free(tmp_ctx);
1177                                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1178                                                  "acl_modify: Error adding new node in object tree.");
1179                         }
1180
1181                         if (!insert_in_object_tree(tmp_ctx,
1182                                                    &attr->attributeSecurityGUID, SEC_ADS_WRITE_PROP,
1183                                                    &new_node, &new_node)) {
1184                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1185                                                        "acl_modify: cannot add to object tree securityGUID\n");
1186                                 ret = LDB_ERR_OPERATIONS_ERROR;
1187                                 goto fail;
1188                         }
1189
1190                         if (!insert_in_object_tree(tmp_ctx,
1191                                                    &attr->schemaIDGUID, SEC_ADS_WRITE_PROP, &new_node, &new_node)) {
1192                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1193                                                        "acl_modify: cannot add to object tree attributeGUID\n");
1194                                 ret = LDB_ERR_OPERATIONS_ERROR;
1195                                 goto fail;
1196                         }
1197
1198                         status = sec_access_check_ds(sd, acl_user_token(module),
1199                                                      SEC_ADS_WRITE_PROP,
1200                                                      &access_granted,
1201                                                      root,
1202                                                      sid);
1203                         if (!NT_STATUS_IS_OK(status)) {
1204                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1205                                                        "Object %s has no write property access\n",
1206                                                        ldb_dn_get_linearized(msg->dn));
1207                                 dsdb_acl_debug(sd,
1208                                                acl_user_token(module),
1209                                                msg->dn,
1210                                                true,
1211                                                10);
1212                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1213                                 goto fail;
1214                         }
1215                 }
1216         }
1217
1218 success:
1219         talloc_free(tmp_ctx);
1220         return ldb_next_request(module, req);
1221 fail:
1222         talloc_free(tmp_ctx);
1223         return ret;
1224 }
1225
1226 /* similar to the modify for the time being.
1227  * We need to consider the special delete tree case, though - TODO */
1228 static int acl_delete(struct ldb_module *module, struct ldb_request *req)
1229 {
1230         int ret;
1231         struct ldb_dn *parent;
1232         struct ldb_context *ldb;
1233         struct ldb_dn *nc_root;
1234         struct ldb_control *as_system;
1235
1236         if (ldb_dn_is_special(req->op.del.dn)) {
1237                 return ldb_next_request(module, req);
1238         }
1239
1240         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1241         if (as_system != NULL) {
1242                 as_system->critical = 0;
1243         }
1244
1245         if (dsdb_module_am_system(module) || as_system) {
1246                 return ldb_next_request(module, req);
1247         }
1248
1249         DEBUG(10, ("ldb:acl_delete: %s\n", ldb_dn_get_linearized(req->op.del.dn)));
1250
1251         ldb = ldb_module_get_ctx(module);
1252
1253         parent = ldb_dn_get_parent(req, req->op.del.dn);
1254         if (parent == NULL) {
1255                 return ldb_oom(ldb);
1256         }
1257
1258         /* Make sure we aren't deleting a NC */
1259
1260         ret = dsdb_find_nc_root(ldb, req, req->op.del.dn, &nc_root);
1261         if (ret != LDB_SUCCESS) {
1262                 return ret;
1263         }
1264         if (ldb_dn_compare(nc_root, req->op.del.dn) == 0) {
1265                 talloc_free(nc_root);
1266                 DEBUG(10,("acl:deleting a NC\n"));
1267                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1268                 return ldb_module_done(req, NULL, NULL,
1269                                        LDB_ERR_UNWILLING_TO_PERFORM);
1270         }
1271         talloc_free(nc_root);
1272
1273         if (ldb_request_get_control(req, LDB_CONTROL_TREE_DELETE_OID)) {
1274                 ret = dsdb_module_check_access_on_dn(module, req,
1275                                                      req->op.del.dn,
1276                                                      SEC_ADS_DELETE_TREE, NULL,
1277                                                      req);
1278                 if (ret != LDB_SUCCESS) {
1279                         return ret;
1280                 }
1281
1282                 return ldb_next_request(module, req);
1283         }
1284
1285         /* First check if we have delete object right */
1286         ret = dsdb_module_check_access_on_dn(module, req, req->op.del.dn,
1287                                              SEC_STD_DELETE, NULL, req);
1288         if (ret == LDB_SUCCESS) {
1289                 return ldb_next_request(module, req);
1290         }
1291
1292         /* Nope, we don't have delete object. Lets check if we have delete
1293          * child on the parent */
1294         ret = dsdb_module_check_access_on_dn(module, req, parent,
1295                                              SEC_ADS_DELETE_CHILD, NULL, req);
1296         if (ret != LDB_SUCCESS) {
1297                 return ret;
1298         }
1299
1300         return ldb_next_request(module, req);
1301 }
1302
1303 static int acl_rename(struct ldb_module *module, struct ldb_request *req)
1304 {
1305         int ret;
1306         struct ldb_dn *oldparent;
1307         struct ldb_dn *newparent;
1308         const struct dsdb_schema *schema;
1309         const struct dsdb_class *objectclass;
1310         struct ldb_context *ldb;
1311         struct security_descriptor *sd = NULL;
1312         struct dom_sid *sid = NULL;
1313         struct ldb_result *acl_res;
1314         const struct GUID *guid;
1315         struct ldb_dn *nc_root;
1316         struct object_tree *root = NULL;
1317         struct object_tree *new_node = NULL;
1318         struct ldb_control *as_system;
1319         TALLOC_CTX *tmp_ctx;
1320         NTSTATUS status;
1321         uint32_t access_granted;
1322         const char *rdn_name;
1323         static const char *acl_attrs[] = {
1324                 "nTSecurityDescriptor",
1325                 "objectClass",
1326                 "objectSid",
1327                 NULL
1328         };
1329
1330         if (ldb_dn_is_special(req->op.rename.olddn)) {
1331                 return ldb_next_request(module, req);
1332         }
1333
1334         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1335         if (as_system != NULL) {
1336                 as_system->critical = 0;
1337         }
1338
1339         DEBUG(10, ("ldb:acl_rename: %s\n", ldb_dn_get_linearized(req->op.rename.olddn)));
1340         if (dsdb_module_am_system(module) || as_system) {
1341                 return ldb_next_request(module, req);
1342         }
1343
1344         ldb = ldb_module_get_ctx(module);
1345
1346         tmp_ctx = talloc_new(req);
1347         if (tmp_ctx == NULL) {
1348                 return ldb_oom(ldb);
1349         }
1350
1351         oldparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.olddn);
1352         if (oldparent == NULL) {
1353                 return ldb_oom(ldb);
1354         }
1355         newparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.newdn);
1356         if (newparent == NULL) {
1357                 return ldb_oom(ldb);
1358         }
1359
1360         /* Make sure we aren't renaming/moving a NC */
1361
1362         ret = dsdb_find_nc_root(ldb, req, req->op.rename.olddn, &nc_root);
1363         if (ret != LDB_SUCCESS) {
1364                 return ret;
1365         }
1366         if (ldb_dn_compare(nc_root, req->op.rename.olddn) == 0) {
1367                 talloc_free(nc_root);
1368                 DEBUG(10,("acl:renaming/moving a NC\n"));
1369                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1370                 return ldb_module_done(req, NULL, NULL,
1371                                        LDB_ERR_UNWILLING_TO_PERFORM);
1372         }
1373         talloc_free(nc_root);
1374
1375         /* Look for the parent */
1376
1377         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res,
1378                                     req->op.rename.olddn, acl_attrs,
1379                                     DSDB_FLAG_NEXT_MODULE |
1380                                     DSDB_FLAG_AS_SYSTEM |
1381                                     DSDB_SEARCH_SHOW_RECYCLED, req);
1382         /* we sould be able to find the parent */
1383         if (ret != LDB_SUCCESS) {
1384                 DEBUG(10,("acl: failed to find object %s\n",
1385                           ldb_dn_get_linearized(req->op.rename.olddn)));
1386                 talloc_free(tmp_ctx);
1387                 return ret;
1388         }
1389
1390         schema = dsdb_get_schema(ldb, acl_res);
1391         if (!schema) {
1392                 talloc_free(tmp_ctx);
1393                 return ldb_operr(ldb);
1394         }
1395
1396         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1397         if (!objectclass) {
1398                 talloc_free(tmp_ctx);
1399                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1400                                  "acl_modify: Error retrieving object class for GUID.");
1401         }
1402
1403         if (!insert_in_object_tree(tmp_ctx, &objectclass->schemaIDGUID, SEC_ADS_WRITE_PROP,
1404                                    &root, &new_node)) {
1405                 talloc_free(tmp_ctx);
1406                 return ldb_operr(ldb);
1407         }
1408
1409         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1410                                                           "name");
1411         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1412                                    &new_node, &new_node)) {
1413                 talloc_free(tmp_ctx);
1414                 return ldb_operr(ldb);
1415         }
1416
1417         rdn_name = ldb_dn_get_rdn_name(req->op.rename.olddn);
1418         if (rdn_name == NULL) {
1419                 talloc_free(tmp_ctx);
1420                 return ldb_operr(ldb);
1421         }
1422         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1423                                                           rdn_name);
1424         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1425                                    &new_node, &new_node)) {
1426                 talloc_free(tmp_ctx);
1427                 return ldb_operr(ldb);
1428         };
1429
1430         ret = dsdb_get_sd_from_ldb_message(ldb, req, acl_res->msgs[0], &sd);
1431
1432         if (ret != LDB_SUCCESS) {
1433                 talloc_free(tmp_ctx);
1434                 return ldb_operr(ldb);
1435         }
1436         /* Theoretically we pass the check if the object has no sd */
1437         if (!sd) {
1438                 talloc_free(tmp_ctx);
1439                 return LDB_SUCCESS;
1440         }
1441         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1442         status = sec_access_check_ds(sd, acl_user_token(module),
1443                                      SEC_ADS_WRITE_PROP,
1444                                      &access_granted,
1445                                      root,
1446                                      sid);
1447
1448         if (!NT_STATUS_IS_OK(status)) {
1449                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1450                                        "Object %s has no wp on name\n",
1451                                        ldb_dn_get_linearized(req->op.rename.olddn));
1452                 dsdb_acl_debug(sd,
1453                           acl_user_token(module),
1454                           req->op.rename.olddn,
1455                           true,
1456                           10);
1457                 talloc_free(tmp_ctx);
1458                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1459         }
1460
1461         if (ldb_dn_compare(oldparent, newparent) == 0) {
1462                 /* regular rename, not move, nothing more to do */
1463                 talloc_free(tmp_ctx);
1464                 return ldb_next_request(module, req);
1465         }
1466
1467         /* new parent should have create child */
1468         root = NULL;
1469         new_node = NULL;
1470
1471         ret = dsdb_module_check_access_on_dn(module, req, newparent,
1472                                              SEC_ADS_CREATE_CHILD,
1473                                              &objectclass->schemaIDGUID, req);
1474         if (ret != LDB_SUCCESS) {
1475                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1476                                        "acl:access_denied renaming %s",
1477                                        ldb_dn_get_linearized(req->op.rename.olddn));
1478                 talloc_free(tmp_ctx);
1479                 return ret;
1480         }
1481         /* do we have delete object on the object? */
1482
1483         status = sec_access_check_ds(sd, acl_user_token(module),
1484                                      SEC_STD_DELETE,
1485                                      &access_granted,
1486                                      NULL,
1487                                      sid);
1488
1489         if (NT_STATUS_IS_OK(status)) {
1490                 talloc_free(tmp_ctx);
1491                 return ldb_next_request(module, req);
1492         }
1493         /* what about delete child on the current parent */
1494         ret = dsdb_module_check_access_on_dn(module, req, oldparent, SEC_ADS_DELETE_CHILD, NULL, req);
1495         if (ret != LDB_SUCCESS) {
1496                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1497                                        "acl:access_denied renaming %s", ldb_dn_get_linearized(req->op.rename.olddn));
1498                 talloc_free(tmp_ctx);
1499                 return ldb_module_done(req, NULL, NULL, ret);
1500         }
1501
1502         talloc_free(tmp_ctx);
1503
1504         return ldb_next_request(module, req);
1505 }
1506
1507 static int acl_search_update_confidential_attrs(struct acl_context *ac,
1508                                                 struct acl_private *data)
1509 {
1510         struct dsdb_attribute *a;
1511         uint32_t n = 0;
1512
1513         if (data->acl_search) {
1514                 /*
1515                  * If acl:search is activated, the acl_read module
1516                  * protects confidential attributes.
1517                  */
1518                 return LDB_SUCCESS;
1519         }
1520
1521         if ((ac->schema == data->cached_schema_ptr) &&
1522             (ac->schema->loaded_usn == data->cached_schema_loaded_usn) &&
1523             (ac->schema->metadata_usn == data->cached_schema_metadata_usn))
1524         {
1525                 return LDB_SUCCESS;
1526         }
1527
1528         data->cached_schema_ptr = NULL;
1529         data->cached_schema_loaded_usn = 0;
1530         data->cached_schema_metadata_usn = 0;
1531         TALLOC_FREE(data->confidential_attrs);
1532
1533         if (ac->schema == NULL) {
1534                 return LDB_SUCCESS;
1535         }
1536
1537         for (a = ac->schema->attributes; a; a = a->next) {
1538                 const char **attrs = data->confidential_attrs;
1539
1540                 if (!(a->searchFlags & SEARCH_FLAG_CONFIDENTIAL)) {
1541                         continue;
1542                 }
1543
1544                 attrs = talloc_realloc(data, attrs, const char *, n + 2);
1545                 if (attrs == NULL) {
1546                         TALLOC_FREE(data->confidential_attrs);
1547                         return ldb_module_oom(ac->module);
1548                 }
1549
1550                 attrs[n] = a->lDAPDisplayName;
1551                 attrs[n+1] = NULL;
1552                 n++;
1553
1554                 data->confidential_attrs = attrs;
1555         }
1556
1557         data->cached_schema_ptr = ac->schema;
1558         data->cached_schema_loaded_usn = ac->schema->loaded_usn;
1559         data->cached_schema_metadata_usn = ac->schema->metadata_usn;
1560
1561         return LDB_SUCCESS;
1562 }
1563
1564 static int acl_search_callback(struct ldb_request *req, struct ldb_reply *ares)
1565 {
1566         struct acl_context *ac;
1567         struct acl_private *data;
1568         struct ldb_result *acl_res;
1569         static const char *acl_attrs[] = {
1570                 "objectClass",
1571                 "nTSecurityDescriptor",
1572                 "objectSid",
1573                 NULL
1574         };
1575         int ret;
1576         unsigned int i;
1577
1578         ac = talloc_get_type(req->context, struct acl_context);
1579         data = talloc_get_type(ldb_module_get_private(ac->module), struct acl_private);
1580         if (!ares) {
1581                 return ldb_module_done(ac->req, NULL, NULL,
1582                                        LDB_ERR_OPERATIONS_ERROR);
1583         }
1584         if (ares->error != LDB_SUCCESS) {
1585                 return ldb_module_done(ac->req, ares->controls,
1586                                        ares->response, ares->error);
1587         }
1588
1589         switch (ares->type) {
1590         case LDB_REPLY_ENTRY:
1591                 if (ac->constructed_attrs) {
1592                         ret = dsdb_module_search_dn(ac->module, ac, &acl_res, ares->message->dn,
1593                                                     acl_attrs,
1594                                                     DSDB_FLAG_NEXT_MODULE |
1595                                                     DSDB_FLAG_AS_SYSTEM |
1596                                                     DSDB_SEARCH_SHOW_RECYCLED,
1597                                                     req);
1598                         if (ret != LDB_SUCCESS) {
1599                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1600                         }
1601                 }
1602
1603                 if (ac->allowedAttributes || ac->allowedAttributesEffective) {
1604                         ret = acl_allowedAttributes(ac->module, ac->schema,
1605                                                     acl_res->msgs[0],
1606                                                     ares->message, ac);
1607                         if (ret != LDB_SUCCESS) {
1608                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1609                         }
1610                 }
1611
1612                 if (ac->allowedChildClasses) {
1613                         ret = acl_childClasses(ac->module, ac->schema,
1614                                                acl_res->msgs[0],
1615                                                ares->message,
1616                                                "allowedChildClasses");
1617                         if (ret != LDB_SUCCESS) {
1618                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1619                         }
1620                 }
1621
1622                 if (ac->allowedChildClassesEffective) {
1623                         ret = acl_childClassesEffective(ac->module, ac->schema,
1624                                                         acl_res->msgs[0],
1625                                                         ares->message, ac);
1626                         if (ret != LDB_SUCCESS) {
1627                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1628                         }
1629                 }
1630
1631                 if (ac->sDRightsEffective) {
1632                         ret = acl_sDRightsEffective(ac->module,
1633                                                     acl_res->msgs[0],
1634                                                     ares->message, ac);
1635                         if (ret != LDB_SUCCESS) {
1636                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1637                         }
1638                 }
1639
1640                 if (data == NULL) {
1641                         return ldb_module_send_entry(ac->req, ares->message,
1642                                                      ares->controls);
1643                 }
1644
1645                 if (ac->am_system) {
1646                         return ldb_module_send_entry(ac->req, ares->message,
1647                                                      ares->controls);
1648                 }
1649
1650                 if (data->password_attrs != NULL) {
1651                         for (i = 0; data->password_attrs[i]; i++) {
1652                                 if ((!ac->userPassword) &&
1653                                     (ldb_attr_cmp(data->password_attrs[i],
1654                                                   "userPassword") == 0))
1655                                 {
1656                                                 continue;
1657                                 }
1658
1659                                 ldb_msg_remove_attr(ares->message, data->password_attrs[i]);
1660                         }
1661                 }
1662
1663                 if (ac->am_administrator) {
1664                         return ldb_module_send_entry(ac->req, ares->message,
1665                                                      ares->controls);
1666                 }
1667
1668                 ret = acl_search_update_confidential_attrs(ac, data);
1669                 if (ret != LDB_SUCCESS) {
1670                         return ret;
1671                 }
1672
1673                 if (data->confidential_attrs != NULL) {
1674                         for (i = 0; data->confidential_attrs[i]; i++) {
1675                                 ldb_msg_remove_attr(ares->message,
1676                                                     data->confidential_attrs[i]);
1677                         }
1678                 }
1679
1680                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
1681
1682         case LDB_REPLY_REFERRAL:
1683                 return ldb_module_send_referral(ac->req, ares->referral);
1684
1685         case LDB_REPLY_DONE:
1686                 return ldb_module_done(ac->req, ares->controls,
1687                                        ares->response, LDB_SUCCESS);
1688
1689         }
1690         return LDB_SUCCESS;
1691 }
1692
1693 static int acl_search(struct ldb_module *module, struct ldb_request *req)
1694 {
1695         struct ldb_context *ldb;
1696         struct acl_context *ac;
1697         struct ldb_parse_tree *down_tree;
1698         struct ldb_request *down_req;
1699         struct acl_private *data;
1700         int ret;
1701         unsigned int i;
1702
1703         if (ldb_dn_is_special(req->op.search.base)) {
1704                 return ldb_next_request(module, req);
1705         }
1706
1707         ldb = ldb_module_get_ctx(module);
1708
1709         ac = talloc_zero(req, struct acl_context);
1710         if (ac == NULL) {
1711                 return ldb_oom(ldb);
1712         }
1713         data = talloc_get_type(ldb_module_get_private(module), struct acl_private);
1714
1715         ac->module = module;
1716         ac->req = req;
1717         ac->am_system = dsdb_module_am_system(module);
1718         ac->am_administrator = dsdb_module_am_administrator(module);
1719         ac->constructed_attrs = false;
1720         ac->modify_search = true;
1721         ac->allowedAttributes = ldb_attr_in_list(req->op.search.attrs, "allowedAttributes");
1722         ac->allowedAttributesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedAttributesEffective");
1723         ac->allowedChildClasses = ldb_attr_in_list(req->op.search.attrs, "allowedChildClasses");
1724         ac->allowedChildClassesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedChildClassesEffective");
1725         ac->sDRightsEffective = ldb_attr_in_list(req->op.search.attrs, "sDRightsEffective");
1726         ac->userPassword = true;
1727         ac->schema = dsdb_get_schema(ldb, ac);
1728
1729         ac->constructed_attrs |= ac->allowedAttributes;
1730         ac->constructed_attrs |= ac->allowedChildClasses;
1731         ac->constructed_attrs |= ac->allowedChildClassesEffective;
1732         ac->constructed_attrs |= ac->allowedAttributesEffective;
1733         ac->constructed_attrs |= ac->sDRightsEffective;
1734
1735         if (data == NULL) {
1736                 ac->modify_search = false;
1737         }
1738         if (ac->am_system) {
1739                 ac->modify_search = false;
1740         }
1741
1742         if (!ac->constructed_attrs && !ac->modify_search) {
1743                 talloc_free(ac);
1744                 return ldb_next_request(module, req);
1745         }
1746
1747         if (!ac->am_system) {
1748                 ac->userPassword = dsdb_user_password_support(module, ac, req);
1749         }
1750
1751         ret = acl_search_update_confidential_attrs(ac, data);
1752         if (ret != LDB_SUCCESS) {
1753                 return ret;
1754         }
1755
1756         down_tree = ldb_parse_tree_copy_shallow(ac, req->op.search.tree);
1757         if (down_tree == NULL) {
1758                 return ldb_oom(ldb);
1759         }
1760
1761         if (!ac->am_system && data->password_attrs) {
1762                 for (i = 0; data->password_attrs[i]; i++) {
1763                         if ((!ac->userPassword) &&
1764                             (ldb_attr_cmp(data->password_attrs[i],
1765                                           "userPassword") == 0))
1766                         {
1767                                 continue;
1768                         }
1769
1770                         ldb_parse_tree_attr_replace(down_tree,
1771                                                     data->password_attrs[i],
1772                                                     "kludgeACLredactedattribute");
1773                 }
1774         }
1775
1776         if (!ac->am_system && !ac->am_administrator && data->confidential_attrs) {
1777                 for (i = 0; data->confidential_attrs[i]; i++) {
1778                         ldb_parse_tree_attr_replace(down_tree,
1779                                                     data->confidential_attrs[i],
1780                                                     "kludgeACLredactedattribute");
1781                 }
1782         }
1783
1784         ret = ldb_build_search_req_ex(&down_req,
1785                                       ldb, ac,
1786                                       req->op.search.base,
1787                                       req->op.search.scope,
1788                                       down_tree,
1789                                       req->op.search.attrs,
1790                                       req->controls,
1791                                       ac, acl_search_callback,
1792                                       req);
1793         LDB_REQ_SET_LOCATION(down_req);
1794         if (ret != LDB_SUCCESS) {
1795                 return ret;
1796         }
1797         /* perform the search */
1798         return ldb_next_request(module, down_req);
1799 }
1800
1801 static int acl_extended(struct ldb_module *module, struct ldb_request *req)
1802 {
1803         struct ldb_context *ldb = ldb_module_get_ctx(module);
1804         struct ldb_control *as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1805
1806         /* allow everybody to read the sequence number */
1807         if (strcmp(req->op.extended.oid,
1808                    LDB_EXTENDED_SEQUENCE_NUMBER) == 0) {
1809                 return ldb_next_request(module, req);
1810         }
1811
1812         if (dsdb_module_am_system(module) ||
1813             dsdb_module_am_administrator(module) || as_system) {
1814                 return ldb_next_request(module, req);
1815         } else {
1816                 ldb_asprintf_errstring(ldb,
1817                                        "acl_extended: "
1818                                        "attempted database modify not permitted. "
1819                                        "User %s is not SYSTEM or an administrator",
1820                                        acl_user_name(req, module));
1821                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1822         }
1823 }
1824
1825 static const struct ldb_module_ops ldb_acl_module_ops = {
1826         .name              = "acl",
1827         .search            = acl_search,
1828         .add               = acl_add,
1829         .modify            = acl_modify,
1830         .del               = acl_delete,
1831         .rename            = acl_rename,
1832         .extended          = acl_extended,
1833         .init_context      = acl_module_init
1834 };
1835
1836 int ldb_acl_module_init(const char *version)
1837 {
1838         LDB_MODULE_CHECK_VERSION(version);
1839         return ldb_register_module(&ldb_acl_module_ops);
1840 }