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_childClassesEffective(struct ldb_module *module,
 344                                      const struct dsdb_schema *schema,
 345                                      struct ldb_message *sd_msg,
 346                                      struct ldb_message *msg,
 347                                      struct acl_context *ac)
 348 {
 349         struct ldb_message_element *oc_el;
 350         struct ldb_message_element *allowedClasses = NULL;
 351         const struct dsdb_class *sclass;
 352         struct security_descriptor *sd;
 353         struct ldb_control *as_system = ldb_request_get_control(ac->req,
 354                                                                 LDB_CONTROL_AS_SYSTEM_OID);
 355         struct dom_sid *sid = NULL;
 356         unsigned int i, j;
 357         int ret;
 358
 359         if (as_system != NULL) {
 360                 as_system->critical = 0;
 361         }
 362
 363         if (ac->am_system || as_system) {
 364                 return acl_childClasses(module, schema, sd_msg, msg, "allowedChildClassesEffective");
 365         }
 366
 367         /* If we don't have a schema yet, we can't do anything... */
 368         if (schema == NULL) {
 369                 ldb_asprintf_errstring(ldb_module_get_ctx(module), "cannot add allowedChildClassesEffective to %s because no schema is loaded", ldb_dn_get_linearized(msg->dn));
 370                 return LDB_ERR_OPERATIONS_ERROR;
 371         }
 372
 373         /* Must remove any existing attribute, or else confusion reins */
 374         ldb_msg_remove_attr(msg, "allowedChildClassesEffective");
 375
 376         oc_el = ldb_msg_find_element(sd_msg, "objectClass");
 377         ret = dsdb_get_sd_from_ldb_message(ldb_module_get_ctx(module), msg, sd_msg, &sd);
 378         if (ret != LDB_SUCCESS) {
 379                 return ret;
 380         }
 381
 382         sid = samdb_result_dom_sid(msg, sd_msg, "objectSid");
 383         for (i=0; oc_el && i < oc_el->num_values; i++) {
 384                 sclass = dsdb_class_by_lDAPDisplayName_ldb_val(schema, &oc_el->values[i]);
 385                 if (!sclass) {
 386                         /* We don't know this class?  what is going on? */
 387                         continue;
 388                 }
 389
 390                 for (j=0; sclass->possibleInferiors && sclass->possibleInferiors[j]; j++) {
 391                         const struct dsdb_class *sc;
 392
 393                         sc = dsdb_class_by_lDAPDisplayName(schema,
 394                                                            sclass->possibleInferiors[j]);
 395                         if (!sc) {
 396                                 /* We don't know this class?  what is going on? */
 397                                 continue;
 398                         }
 399
 400                         ret = acl_check_access_on_objectclass(module, ac,
 401                                                               sd, sid,
 402                                                               SEC_ADS_CREATE_CHILD,
 403                                                               sc);
 404                         if (ret == LDB_SUCCESS) {
 405                                 ldb_msg_add_string(msg, "allowedChildClassesEffective",
 406                                                    sclass->possibleInferiors[j]);
 407                         }
 408                 }
 409         }
 410         allowedClasses = ldb_msg_find_element(msg, "allowedChildClassesEffective");
 411         if (!allowedClasses) {
 412                 return LDB_SUCCESS;
 413         }
 414
 415         if (allowedClasses->num_values > 1) {
 416                 TYPESAFE_QSORT(allowedClasses->values, allowedClasses->num_values, data_blob_cmp);
 417                 for (i=1 ; i < allowedClasses->num_values; i++) {
 418                         struct ldb_val *val1 = &allowedClasses->values[i-1];
 419                         struct ldb_val *val2 = &allowedClasses->values[i];
 420                         if (data_blob_cmp(val1, val2) == 0) {
 421                                 memmove(val1, val2, (allowedClasses->num_values - i) * sizeof( struct ldb_val));
 422                                 allowedClasses->num_values--;
 423                                 i--;
 424                         }
 425                 }
 426         }
 427         return LDB_SUCCESS;
 428 }
 429
 430 static int acl_sDRightsEffective(struct ldb_module *module,
 431                                  struct ldb_message *sd_msg,
 432                                  struct ldb_message *msg,
 433                                  struct acl_context *ac)
 434 {
 435         struct ldb_context *ldb = ldb_module_get_ctx(module);
 436         struct ldb_message_element *rightsEffective;
 437         int ret;
 438         struct security_descriptor *sd;
 439         struct ldb_control *as_system = ldb_request_get_control(ac->req,
 440                                                                 LDB_CONTROL_AS_SYSTEM_OID);
 441         struct dom_sid *sid = NULL;
 442         uint32_t flags = 0;
 443
 444         if (as_system != NULL) {
 445                 as_system->critical = 0;
 446         }
 447
 448         /* Must remove any existing attribute, or else confusion reins */
 449         ldb_msg_remove_attr(msg, "sDRightsEffective");
 450         ret = ldb_msg_add_empty(msg, "sDRightsEffective", 0, &rightsEffective);
 451         if (ret != LDB_SUCCESS) {
 452                 return ret;
 453         }
 454         if (ac->am_system || as_system) {
 455                 flags = SECINFO_OWNER | SECINFO_GROUP |  SECINFO_SACL |  SECINFO_DACL;
 456         } else {
 457                 const struct dsdb_class *objectclass;
 458                 const struct dsdb_attribute *attr;
 459
 460                 objectclass = dsdb_get_structural_oc_from_msg(ac->schema, sd_msg);
 461                 if (objectclass == NULL) {
 462                         return ldb_operr(ldb);
 463                 }
 464
 465                 attr = dsdb_attribute_by_lDAPDisplayName(ac->schema,
 466                                                          "nTSecurityDescriptor");
 467                 if (attr == NULL) {
 468                         return ldb_operr(ldb);
 469                 }
 470
 471                 /* Get the security descriptor from the message */
 472                 ret = dsdb_get_sd_from_ldb_message(ldb, msg, sd_msg, &sd);
 473                 if (ret != LDB_SUCCESS) {
 474                         return ret;
 475                 }
 476                 sid = samdb_result_dom_sid(msg, sd_msg, "objectSid");
 477                 ret = acl_check_access_on_attribute(module,
 478                                                     msg,
 479                                                     sd,
 480                                                     sid,
 481                                                     SEC_STD_WRITE_OWNER,
 482                                                     attr,
 483                                                     objectclass);
 484                 if (ret == LDB_SUCCESS) {
 485                         flags |= SECINFO_OWNER | SECINFO_GROUP;
 486                 }
 487                 ret = acl_check_access_on_attribute(module,
 488                                                     msg,
 489                                                     sd,
 490                                                     sid,
 491                                                     SEC_STD_WRITE_DAC,
 492                                                     attr,
 493                                                     objectclass);
 494                 if (ret == LDB_SUCCESS) {
 495                         flags |= SECINFO_DACL;
 496                 }
 497                 ret = acl_check_access_on_attribute(module,
 498                                                     msg,
 499                                                     sd,
 500                                                     sid,
 501                                                     SEC_FLAG_SYSTEM_SECURITY,
 502                                                     attr,
 503                                                     objectclass);
 504                 if (ret == LDB_SUCCESS) {
 505                         flags |= SECINFO_SACL;
 506                 }
 507         }
 508         return samdb_msg_add_uint(ldb_module_get_ctx(module), msg, msg,
 509                                   "sDRightsEffective", flags);
 510 }
 511
 512 static int acl_validate_spn_value(TALLOC_CTX *mem_ctx,
 513                                   struct ldb_context *ldb,
 514                                   const char *spn_value,
 515                                   uint32_t userAccountControl,
 516                                   const char *samAccountName,
 517                                   const char *dnsHostName,
 518                                   const char *netbios_name,
 519                                   const char *ntds_guid)
 520 {
 521         int ret;
 522         krb5_context krb_ctx;
 523         krb5_error_code kerr;
 524         krb5_principal principal;
 525         char *instanceName;
 526         char *serviceType;
 527         char *serviceName;
 528         const char *forest_name = samdb_forest_name(ldb, mem_ctx);
 529         const char *base_domain = samdb_default_domain_name(ldb, mem_ctx);
 530         struct loadparm_context *lp_ctx = talloc_get_type(ldb_get_opaque(ldb, "loadparm"),
 531                                                           struct loadparm_context);
 532         bool is_dc = (userAccountControl & UF_SERVER_TRUST_ACCOUNT) ||
 533                 (userAccountControl & UF_PARTIAL_SECRETS_ACCOUNT);
 534
 535         if (strcasecmp_m(spn_value, samAccountName) == 0) {
 536                 /* MacOS X sets this value, and setting an SPN of your
 537                  * own samAccountName is both pointless and safe */
 538                 return LDB_SUCCESS;
 539         }
 540
 541         kerr = smb_krb5_init_context_basic(mem_ctx,
 542                                            lp_ctx,
 543                                            &krb_ctx);
 544         if (kerr != 0) {
 545                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 546                                  "Could not initialize kerberos context.");
 547         }
 548
 549         ret = krb5_parse_name(krb_ctx, spn_value, &principal);
 550         if (ret) {
 551                 krb5_free_context(krb_ctx);
 552                 return LDB_ERR_CONSTRAINT_VIOLATION;
 553         }
 554
 555         if (principal->name.name_string.len < 2) {
 556                 goto fail;
 557         }
 558
 559         instanceName = principal->name.name_string.val[1];
 560         serviceType = principal->name.name_string.val[0];
 561         if (principal->name.name_string.len == 3) {
 562                 serviceName = principal->name.name_string.val[2];
 563         } else {
 564                 serviceName = NULL;
 565         }
 566
 567         if (serviceName) {
 568                 if (!is_dc) {
 569                         goto fail;
 570                 }
 571                 if (strcasecmp(serviceType, "ldap") == 0) {
 572                         if (strcasecmp(serviceName, netbios_name) != 0 &&
 573                             strcasecmp(serviceName, forest_name) != 0) {
 574                                 goto fail;
 575                         }
 576
 577                 } else if (strcasecmp(serviceType, "gc") == 0) {
 578                         if (strcasecmp(serviceName, forest_name) != 0) {
 579                                 goto fail;
 580                         }
 581                 } else {
 582                         if (strcasecmp(serviceName, base_domain) != 0 &&
 583                             strcasecmp(serviceName, netbios_name) != 0) {
 584                                 goto fail;
 585                         }
 586                 }
 587         }
 588         /* instanceName can be samAccountName without $ or dnsHostName
 589          * or "ntds_guid._msdcs.forest_domain for DC objects */
 590         if (strlen(instanceName) == (strlen(samAccountName) - 1)
 591             && strncasecmp(instanceName, samAccountName, strlen(samAccountName) - 1) == 0) {
 592                 goto success;
 593         } else if (dnsHostName != NULL && strcasecmp(instanceName, dnsHostName) == 0) {
 594                 goto success;
 595         } else if (is_dc) {
 596                 const char *guid_str;
 597                 guid_str = talloc_asprintf(mem_ctx,"%s._msdcs.%s",
 598                                            ntds_guid,
 599                                            forest_name);
 600                 if (strcasecmp(instanceName, guid_str) == 0) {
 601                         goto success;
 602                 }
 603         }
 604
 605 fail:
 606         krb5_free_principal(krb_ctx, principal);
 607         krb5_free_context(krb_ctx);
 608         return LDB_ERR_CONSTRAINT_VIOLATION;
 609
 610 success:
 611         krb5_free_principal(krb_ctx, principal);
 612         krb5_free_context(krb_ctx);
 613         return LDB_SUCCESS;
 614 }
 615
 616 static int acl_check_spn(TALLOC_CTX *mem_ctx,
 617                          struct ldb_module *module,
 618                          struct ldb_request *req,
 619                          struct security_descriptor *sd,
 620                          struct dom_sid *sid,
 621                          const struct dsdb_attribute *attr,
 622                          const struct dsdb_class *objectclass)
 623 {
 624         int ret;
 625         unsigned int i;
 626         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 627         struct ldb_context *ldb = ldb_module_get_ctx(module);
 628         struct ldb_result *acl_res;
 629         struct ldb_result *netbios_res;
 630         struct ldb_message_element *el;
 631         struct ldb_dn *partitions_dn = samdb_partitions_dn(ldb, tmp_ctx);
 632         uint32_t userAccountControl;
 633         const char *samAccountName;
 634         const char *dnsHostName;
 635         const char *netbios_name;
 636         struct GUID ntds;
 637         char *ntds_guid = NULL;
 638
 639         static const char *acl_attrs[] = {
 640                 "samAccountName",
 641                 "dnsHostName",
 642                 "userAccountControl",
 643                 NULL
 644         };
 645         static const char *netbios_attrs[] = {
 646                 "nETBIOSName",
 647                 NULL
 648         };
 649
 650         /* if we have wp, we can do whatever we like */
 651         if (acl_check_access_on_attribute(module,
 652                                           tmp_ctx,
 653                                           sd,
 654                                           sid,
 655                                           SEC_ADS_WRITE_PROP,
 656                                           attr, objectclass) == LDB_SUCCESS) {
 657                 talloc_free(tmp_ctx);
 658                 return LDB_SUCCESS;
 659         }
 660
 661         ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 662                                        GUID_DRS_VALIDATE_SPN,
 663                                        SEC_ADS_SELF_WRITE,
 664                                        sid);
 665
 666         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 667                 dsdb_acl_debug(sd, acl_user_token(module),
 668                                req->op.mod.message->dn,
 669                                true,
 670                                10);
 671                 talloc_free(tmp_ctx);
 672                 return ret;
 673         }
 674
 675         ret = dsdb_module_search_dn(module, tmp_ctx,
 676                                     &acl_res, req->op.mod.message->dn,
 677                                     acl_attrs,
 678                                     DSDB_FLAG_NEXT_MODULE |
 679                                     DSDB_FLAG_AS_SYSTEM |
 680                                     DSDB_SEARCH_SHOW_RECYCLED,
 681                                     req);
 682         if (ret != LDB_SUCCESS) {
 683                 talloc_free(tmp_ctx);
 684                 return ret;
 685         }
 686
 687         userAccountControl = ldb_msg_find_attr_as_uint(acl_res->msgs[0], "userAccountControl", 0);
 688         dnsHostName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "dnsHostName", NULL);
 689         samAccountName = ldb_msg_find_attr_as_string(acl_res->msgs[0], "samAccountName", NULL);
 690
 691         ret = dsdb_module_search(module, tmp_ctx,
 692                                  &netbios_res, partitions_dn,
 693                                  LDB_SCOPE_ONELEVEL,
 694                                  netbios_attrs,
 695                                  DSDB_FLAG_NEXT_MODULE |
 696                                  DSDB_FLAG_AS_SYSTEM,
 697                                  req,
 698                                  "(ncName=%s)",
 699                                  ldb_dn_get_linearized(ldb_get_default_basedn(ldb)));
 700
 701         netbios_name = ldb_msg_find_attr_as_string(netbios_res->msgs[0], "nETBIOSName", NULL);
 702
 703         el = ldb_msg_find_element(req->op.mod.message, "servicePrincipalName");
 704         if (!el) {
 705                 talloc_free(tmp_ctx);
 706                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
 707                                          "Error finding element for servicePrincipalName.");
 708         }
 709
 710         /* NTDSDSA objectGuid of object we are checking SPN for */
 711         if (userAccountControl & (UF_SERVER_TRUST_ACCOUNT | UF_PARTIAL_SECRETS_ACCOUNT)) {
 712                 ret = dsdb_module_find_ntdsguid_for_computer(module, tmp_ctx,
 713                                                              req->op.mod.message->dn, &ntds, req);
 714                 if (ret != LDB_SUCCESS) {
 715                         ldb_asprintf_errstring(ldb, "Failed to find NTDSDSA objectGuid for %s: %s",
 716                                                ldb_dn_get_linearized(req->op.mod.message->dn),
 717                                                ldb_strerror(ret));
 718                         talloc_free(tmp_ctx);
 719                         return LDB_ERR_OPERATIONS_ERROR;
 720                 }
 721                 ntds_guid = GUID_string(tmp_ctx, &ntds);
 722         }
 723
 724         for (i=0; i < el->num_values; i++) {
 725                 ret = acl_validate_spn_value(tmp_ctx,
 726                                              ldb,
 727                                              (char *)el->values[i].data,
 728                                              userAccountControl,
 729                                              samAccountName,
 730                                              dnsHostName,
 731                                              netbios_name,
 732                                              ntds_guid);
 733                 if (ret != LDB_SUCCESS) {
 734                         talloc_free(tmp_ctx);
 735                         return ret;
 736                 }
 737         }
 738         talloc_free(tmp_ctx);
 739         return LDB_SUCCESS;
 740 }
 741
 742 static int acl_add(struct ldb_module *module, struct ldb_request *req)
 743 {
 744         int ret;
 745         struct ldb_dn *parent;
 746         struct ldb_context *ldb;
 747         const struct dsdb_schema *schema;
 748         const struct dsdb_class *objectclass;
 749         struct ldb_dn *nc_root;
 750         struct ldb_control *as_system;
 751
 752         if (ldb_dn_is_special(req->op.add.message->dn)) {
 753                 return ldb_next_request(module, req);
 754         }
 755
 756         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
 757         if (as_system != NULL) {
 758                 as_system->critical = 0;
 759         }
 760
 761         if (dsdb_module_am_system(module) || as_system) {
 762                 return ldb_next_request(module, req);
 763         }
 764
 765         ldb = ldb_module_get_ctx(module);
 766
 767         parent = ldb_dn_get_parent(req, req->op.add.message->dn);
 768         if (parent == NULL) {
 769                 return ldb_oom(ldb);
 770         }
 771
 772         /* Creating an NC. There is probably something we should do here,
 773          * but we will establish that later */
 774
 775         ret = dsdb_find_nc_root(ldb, req, req->op.add.message->dn, &nc_root);
 776         if (ret != LDB_SUCCESS) {
 777                 return ret;
 778         }
 779         if (ldb_dn_compare(nc_root, req->op.add.message->dn) == 0) {
 780                 talloc_free(nc_root);
 781                 return ldb_next_request(module, req);
 782         }
 783         talloc_free(nc_root);
 784
 785         schema = dsdb_get_schema(ldb, req);
 786         if (!schema) {
 787                 return ldb_operr(ldb);
 788         }
 789
 790         objectclass = dsdb_get_structural_oc_from_msg(schema, req->op.add.message);
 791         if (!objectclass) {
 792                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
 793                                        "acl: unable to find or validate structrual objectClass on %s\n",
 794                                        ldb_dn_get_linearized(req->op.add.message->dn));
 795                 return ldb_module_done(req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR);
 796         }
 797
 798         ret = dsdb_module_check_access_on_dn(module, req, parent,
 799                                              SEC_ADS_CREATE_CHILD,
 800                                              &objectclass->schemaIDGUID, req);
 801         if (ret != LDB_SUCCESS) {
 802                 return ret;
 803         }
 804         return ldb_next_request(module, req);
 805 }
 806
 807 /* ckecks if modifications are allowed on "Member" attribute */
 808 static int acl_check_self_membership(TALLOC_CTX *mem_ctx,
 809                                      struct ldb_module *module,
 810                                      struct ldb_request *req,
 811                                      struct security_descriptor *sd,
 812                                      struct dom_sid *sid,
 813                                      const struct dsdb_attribute *attr,
 814                                      const struct dsdb_class *objectclass)
 815 {
 816         int ret;
 817         unsigned int i;
 818         struct ldb_context *ldb = ldb_module_get_ctx(module);
 819         struct ldb_dn *user_dn;
 820         struct ldb_message_element *member_el;
 821         /* if we have wp, we can do whatever we like */
 822         if (acl_check_access_on_attribute(module,
 823                                           mem_ctx,
 824                                           sd,
 825                                           sid,
 826                                           SEC_ADS_WRITE_PROP,
 827                                           attr, objectclass) == LDB_SUCCESS) {
 828                 return LDB_SUCCESS;
 829         }
 830         /* if we are adding/deleting ourselves, check for self membership */
 831         ret = dsdb_find_dn_by_sid(ldb, mem_ctx,
 832                                   &acl_user_token(module)->sids[PRIMARY_USER_SID_INDEX],
 833                                   &user_dn);
 834         if (ret != LDB_SUCCESS) {
 835                 return ret;
 836         }
 837         member_el = ldb_msg_find_element(req->op.mod.message, "member");
 838         if (!member_el) {
 839                 return ldb_operr(ldb);
 840         }
 841         /* user can only remove oneself */
 842         if (member_el->num_values == 0) {
 843                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 844         }
 845         for (i = 0; i < member_el->num_values; i++) {
 846                 if (strcasecmp((const char *)member_el->values[i].data,
 847                                ldb_dn_get_extended_linearized(mem_ctx, user_dn, 1)) != 0) {
 848                         return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
 849                 }
 850         }
 851         ret = acl_check_extended_right(mem_ctx, sd, acl_user_token(module),
 852                                        GUID_DRS_SELF_MEMBERSHIP,
 853                                        SEC_ADS_SELF_WRITE,
 854                                        sid);
 855         if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 856                 dsdb_acl_debug(sd, acl_user_token(module),
 857                                req->op.mod.message->dn,
 858                                true,
 859                                10);
 860         }
 861         return ret;
 862 }
 863
 864 static int acl_check_password_rights(TALLOC_CTX *mem_ctx,
 865                                      struct ldb_module *module,
 866                                      struct ldb_request *req,
 867                                      struct security_descriptor *sd,
 868                                      struct dom_sid *sid,
 869                                      const struct dsdb_class *objectclass,
 870                                      bool userPassword)
 871 {
 872         int ret = LDB_SUCCESS;
 873         unsigned int del_attr_cnt = 0, add_attr_cnt = 0, rep_attr_cnt = 0;
 874         struct ldb_message_element *el;
 875         struct ldb_message *msg;
 876         const char *passwordAttrs[] = { "userPassword", "clearTextPassword",
 877                                         "unicodePwd", "dBCSPwd", NULL }, **l;
 878         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 879
 880         msg = ldb_msg_copy_shallow(tmp_ctx, req->op.mod.message);
 881         if (msg == NULL) {
 882                 return ldb_module_oom(module);
 883         }
 884         for (l = passwordAttrs; *l != NULL; l++) {
 885                 if ((!userPassword) && (ldb_attr_cmp(*l, "userPassword") == 0)) {
 886                         continue;
 887                 }
 888
 889                 while ((el = ldb_msg_find_element(msg, *l)) != NULL) {
 890                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_DELETE) {
 891                                 ++del_attr_cnt;
 892                         }
 893                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_ADD) {
 894                                 ++add_attr_cnt;
 895                         }
 896                         if (LDB_FLAG_MOD_TYPE(el->flags) == LDB_FLAG_MOD_REPLACE) {
 897                                 ++rep_attr_cnt;
 898                         }
 899                         ldb_msg_remove_element(msg, el);
 900                 }
 901         }
 902
 903         /* single deletes will be handled by the "password_hash" LDB module
 904          * later in the stack, so we let it though here */
 905         if ((del_attr_cnt > 0) && (add_attr_cnt == 0) && (rep_attr_cnt == 0)) {
 906                 talloc_free(tmp_ctx);
 907                 return LDB_SUCCESS;
 908         }
 909
 910         if (ldb_request_get_control(req,
 911                                     DSDB_CONTROL_PASSWORD_CHANGE_OID) != NULL) {
 912                 /* The "DSDB_CONTROL_PASSWORD_CHANGE_OID" control means that we
 913                  * have a user password change and not a set as the message
 914                  * looks like. In it's value blob it contains the NT and/or LM
 915                  * hash of the old password specified by the user.
 916                  * This control is used by the SAMR and "kpasswd" password
 917                  * change mechanisms. */
 918                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 919                                                GUID_DRS_USER_CHANGE_PASSWORD,
 920                                                SEC_ADS_CONTROL_ACCESS,
 921                                                sid);
 922         }
 923         else if (rep_attr_cnt > 0 || (add_attr_cnt != del_attr_cnt)) {
 924                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 925                                                GUID_DRS_FORCE_CHANGE_PASSWORD,
 926                                                SEC_ADS_CONTROL_ACCESS,
 927                                                sid);
 928         }
 929         else if (add_attr_cnt == 1 && del_attr_cnt == 1) {
 930                 ret = acl_check_extended_right(tmp_ctx, sd, acl_user_token(module),
 931                                                GUID_DRS_USER_CHANGE_PASSWORD,
 932                                                SEC_ADS_CONTROL_ACCESS,
 933                                                sid);
 934                 /* Very strange, but we get constraint violation in this case */
 935                 if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) {
 936                         ret = LDB_ERR_CONSTRAINT_VIOLATION;
 937                 }
 938         }
 939         if (ret != LDB_SUCCESS) {
 940                 dsdb_acl_debug(sd, acl_user_token(module),
 941                                req->op.mod.message->dn,
 942                                true,
 943                                10);
 944         }
 945         talloc_free(tmp_ctx);
 946         return ret;
 947 }
 948
 949
 950 static int acl_modify(struct ldb_module *module, struct ldb_request *req)
 951 {
 952         int ret;
 953         struct ldb_context *ldb = ldb_module_get_ctx(module);
 954         const struct dsdb_schema *schema;
 955         unsigned int i;
 956         const struct dsdb_class *objectclass;
 957         uint32_t access_granted;
 958         NTSTATUS status;
 959         struct ldb_result *acl_res;
 960         struct security_descriptor *sd;
 961         struct dom_sid *sid = NULL;
 962         struct ldb_control *as_system;
 963         bool userPassword;
 964         TALLOC_CTX *tmp_ctx;
 965         const struct ldb_message *msg = req->op.mod.message;
 966         static const char *acl_attrs[] = {
 967                 "nTSecurityDescriptor",
 968                 "objectClass",
 969                 "objectSid",
 970                 NULL
 971         };
 972
 973         if (ldb_dn_is_special(msg->dn)) {
 974                 return ldb_next_request(module, req);
 975         }
 976
 977         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
 978         if (as_system != NULL) {
 979                 as_system->critical = 0;
 980         }
 981
 982         /* Don't print this debug statement if elements[0].name is going to be NULL */
 983         if (msg->num_elements > 0) {
 984                 DEBUG(10, ("ldb:acl_modify: %s\n", msg->elements[0].name));
 985         }
 986         if (dsdb_module_am_system(module) || as_system) {
 987                 return ldb_next_request(module, req);
 988         }
 989
 990         tmp_ctx = talloc_new(req);
 991         if (tmp_ctx == NULL) {
 992                 return ldb_oom(ldb);
 993         }
 994
 995         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res, msg->dn,
 996                                     acl_attrs,
 997                                     DSDB_FLAG_NEXT_MODULE |
 998                                     DSDB_FLAG_AS_SYSTEM |
 999                                     DSDB_SEARCH_SHOW_RECYCLED,
1000                                     req);
1001
1002         if (ret != LDB_SUCCESS) {
1003                 goto fail;
1004         }
1005
1006         userPassword = dsdb_user_password_support(module, req, req);
1007
1008         schema = dsdb_get_schema(ldb, tmp_ctx);
1009         if (!schema) {
1010                 talloc_free(tmp_ctx);
1011                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1012                                  "acl_modify: Error obtaining schema.");
1013         }
1014
1015         ret = dsdb_get_sd_from_ldb_message(ldb, tmp_ctx, acl_res->msgs[0], &sd);
1016         if (ret != LDB_SUCCESS) {
1017                 talloc_free(tmp_ctx);
1018                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1019                                  "acl_modify: Error retrieving security descriptor.");
1020         }
1021         /* Theoretically we pass the check if the object has no sd */
1022         if (!sd) {
1023                 goto success;
1024         }
1025
1026         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1027         if (!objectclass) {
1028                 talloc_free(tmp_ctx);
1029                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1030                                  "acl_modify: Error retrieving object class for GUID.");
1031         }
1032         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1033         for (i=0; i < msg->num_elements; i++) {
1034                 const struct ldb_message_element *el = &msg->elements[i];
1035                 const struct dsdb_attribute *attr;
1036
1037                 /*
1038                  * This basic attribute existence check with the right errorcode
1039                  * is needed since this module is the first one which requests
1040                  * schema attribute information.
1041                  * The complete attribute checking is done in the
1042                  * "objectclass_attrs" module behind this one.
1043                  *
1044                  * NOTE: "clearTextPassword" is not defined in the schema.
1045                  */
1046                 attr = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
1047                 if (!attr && ldb_attr_cmp("clearTextPassword", el->name) != 0) {
1048                         ldb_asprintf_errstring(ldb, "acl_modify: attribute '%s' "
1049                                                "on entry '%s' was not found in the schema!",
1050                                                req->op.mod.message->elements[i].name,
1051                                        ldb_dn_get_linearized(req->op.mod.message->dn));
1052                         ret =  LDB_ERR_NO_SUCH_ATTRIBUTE;
1053                         goto fail;
1054                 }
1055
1056                 if (ldb_attr_cmp("nTSecurityDescriptor", el->name) == 0) {
1057                         uint32_t sd_flags = dsdb_request_sd_flags(req, NULL);
1058                         uint32_t access_mask = 0;
1059
1060                         if (sd_flags & (SECINFO_OWNER|SECINFO_GROUP)) {
1061                                 access_mask |= SEC_STD_WRITE_OWNER;
1062                         }
1063                         if (sd_flags & SECINFO_DACL) {
1064                                 access_mask |= SEC_STD_WRITE_DAC;
1065                         }
1066                         if (sd_flags & SECINFO_SACL) {
1067                                 access_mask |= SEC_FLAG_SYSTEM_SECURITY;
1068                         }
1069
1070                         status = sec_access_check_ds(sd, acl_user_token(module),
1071                                              access_mask,
1072                                              &access_granted,
1073                                              NULL,
1074                                              sid);
1075
1076                         if (!NT_STATUS_IS_OK(status)) {
1077                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1078                                                        "Object %s has no write dacl access\n",
1079                                                        ldb_dn_get_linearized(msg->dn));
1080                                 dsdb_acl_debug(sd,
1081                                                acl_user_token(module),
1082                                                msg->dn,
1083                                                true,
1084                                                10);
1085                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1086                                 goto fail;
1087                         }
1088                 } else if (ldb_attr_cmp("member", el->name) == 0) {
1089                         ret = acl_check_self_membership(tmp_ctx,
1090                                                         module,
1091                                                         req,
1092                                                         sd,
1093                                                         sid,
1094                                                         attr,
1095                                                         objectclass);
1096                         if (ret != LDB_SUCCESS) {
1097                                 goto fail;
1098                         }
1099                 } else if (ldb_attr_cmp("dBCSPwd", el->name) == 0) {
1100                         /* this one is not affected by any rights, we should let it through
1101                            so that passwords_hash returns the correct error */
1102                         continue;
1103                 } else if (ldb_attr_cmp("unicodePwd", el->name) == 0 ||
1104                            (userPassword && ldb_attr_cmp("userPassword", el->name) == 0) ||
1105                            ldb_attr_cmp("clearTextPassword", el->name) == 0) {
1106                         ret = acl_check_password_rights(tmp_ctx,
1107                                                         module,
1108                                                         req,
1109                                                         sd,
1110                                                         sid,
1111                                                         objectclass,
1112                                                         userPassword);
1113                         if (ret != LDB_SUCCESS) {
1114                                 goto fail;
1115                         }
1116                 } else if (ldb_attr_cmp("servicePrincipalName", el->name) == 0) {
1117                         ret = acl_check_spn(tmp_ctx,
1118                                             module,
1119                                             req,
1120                                             sd,
1121                                             sid,
1122                                             attr,
1123                                             objectclass);
1124                         if (ret != LDB_SUCCESS) {
1125                                 goto fail;
1126                         }
1127                 } else {
1128                         struct object_tree *root = NULL;
1129                         struct object_tree *new_node = NULL;
1130
1131                         if (!insert_in_object_tree(tmp_ctx,
1132                                                    &objectclass->schemaIDGUID,
1133                                                    SEC_ADS_WRITE_PROP,
1134                                                    &root, &new_node)) {
1135                                 talloc_free(tmp_ctx);
1136                                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1137                                                  "acl_modify: Error adding new node in object tree.");
1138                         }
1139
1140                         if (!insert_in_object_tree(tmp_ctx,
1141                                                    &attr->attributeSecurityGUID, SEC_ADS_WRITE_PROP,
1142                                                    &new_node, &new_node)) {
1143                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1144                                                        "acl_modify: cannot add to object tree securityGUID\n");
1145                                 ret = LDB_ERR_OPERATIONS_ERROR;
1146                                 goto fail;
1147                         }
1148
1149                         if (!insert_in_object_tree(tmp_ctx,
1150                                                    &attr->schemaIDGUID, SEC_ADS_WRITE_PROP, &new_node, &new_node)) {
1151                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1152                                                        "acl_modify: cannot add to object tree attributeGUID\n");
1153                                 ret = LDB_ERR_OPERATIONS_ERROR;
1154                                 goto fail;
1155                         }
1156
1157                         status = sec_access_check_ds(sd, acl_user_token(module),
1158                                                      SEC_ADS_WRITE_PROP,
1159                                                      &access_granted,
1160                                                      root,
1161                                                      sid);
1162                         if (!NT_STATUS_IS_OK(status)) {
1163                                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1164                                                        "Object %s has no write property access\n",
1165                                                        ldb_dn_get_linearized(msg->dn));
1166                                 dsdb_acl_debug(sd,
1167                                                acl_user_token(module),
1168                                                msg->dn,
1169                                                true,
1170                                                10);
1171                                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1172                                 goto fail;
1173                         }
1174                 }
1175         }
1176
1177 success:
1178         talloc_free(tmp_ctx);
1179         return ldb_next_request(module, req);
1180 fail:
1181         talloc_free(tmp_ctx);
1182         return ret;
1183 }
1184
1185 /* similar to the modify for the time being.
1186  * We need to consider the special delete tree case, though - TODO */
1187 static int acl_delete(struct ldb_module *module, struct ldb_request *req)
1188 {
1189         int ret;
1190         struct ldb_dn *parent;
1191         struct ldb_context *ldb;
1192         struct ldb_dn *nc_root;
1193         struct ldb_control *as_system;
1194
1195         if (ldb_dn_is_special(req->op.del.dn)) {
1196                 return ldb_next_request(module, req);
1197         }
1198
1199         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1200         if (as_system != NULL) {
1201                 as_system->critical = 0;
1202         }
1203
1204         if (dsdb_module_am_system(module) || as_system) {
1205                 return ldb_next_request(module, req);
1206         }
1207
1208         DEBUG(10, ("ldb:acl_delete: %s\n", ldb_dn_get_linearized(req->op.del.dn)));
1209
1210         ldb = ldb_module_get_ctx(module);
1211
1212         parent = ldb_dn_get_parent(req, req->op.del.dn);
1213         if (parent == NULL) {
1214                 return ldb_oom(ldb);
1215         }
1216
1217         /* Make sure we aren't deleting a NC */
1218
1219         ret = dsdb_find_nc_root(ldb, req, req->op.del.dn, &nc_root);
1220         if (ret != LDB_SUCCESS) {
1221                 return ret;
1222         }
1223         if (ldb_dn_compare(nc_root, req->op.del.dn) == 0) {
1224                 talloc_free(nc_root);
1225                 DEBUG(10,("acl:deleting a NC\n"));
1226                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1227                 return ldb_module_done(req, NULL, NULL,
1228                                        LDB_ERR_UNWILLING_TO_PERFORM);
1229         }
1230         talloc_free(nc_root);
1231
1232         if (ldb_request_get_control(req, LDB_CONTROL_TREE_DELETE_OID)) {
1233                 ret = dsdb_module_check_access_on_dn(module, req,
1234                                                      req->op.del.dn,
1235                                                      SEC_ADS_DELETE_TREE, NULL,
1236                                                      req);
1237                 if (ret != LDB_SUCCESS) {
1238                         return ret;
1239                 }
1240
1241                 return ldb_next_request(module, req);
1242         }
1243
1244         /* First check if we have delete object right */
1245         ret = dsdb_module_check_access_on_dn(module, req, req->op.del.dn,
1246                                              SEC_STD_DELETE, NULL, req);
1247         if (ret == LDB_SUCCESS) {
1248                 return ldb_next_request(module, req);
1249         }
1250
1251         /* Nope, we don't have delete object. Lets check if we have delete
1252          * child on the parent */
1253         ret = dsdb_module_check_access_on_dn(module, req, parent,
1254                                              SEC_ADS_DELETE_CHILD, NULL, req);
1255         if (ret != LDB_SUCCESS) {
1256                 return ret;
1257         }
1258
1259         return ldb_next_request(module, req);
1260 }
1261
1262 static int acl_rename(struct ldb_module *module, struct ldb_request *req)
1263 {
1264         int ret;
1265         struct ldb_dn *oldparent;
1266         struct ldb_dn *newparent;
1267         const struct dsdb_schema *schema;
1268         const struct dsdb_class *objectclass;
1269         struct ldb_context *ldb;
1270         struct security_descriptor *sd = NULL;
1271         struct dom_sid *sid = NULL;
1272         struct ldb_result *acl_res;
1273         const struct GUID *guid;
1274         struct ldb_dn *nc_root;
1275         struct object_tree *root = NULL;
1276         struct object_tree *new_node = NULL;
1277         struct ldb_control *as_system;
1278         TALLOC_CTX *tmp_ctx;
1279         NTSTATUS status;
1280         uint32_t access_granted;
1281         const char *rdn_name;
1282         static const char *acl_attrs[] = {
1283                 "nTSecurityDescriptor",
1284                 "objectClass",
1285                 "objectSid",
1286                 NULL
1287         };
1288
1289         if (ldb_dn_is_special(req->op.rename.olddn)) {
1290                 return ldb_next_request(module, req);
1291         }
1292
1293         as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1294         if (as_system != NULL) {
1295                 as_system->critical = 0;
1296         }
1297
1298         DEBUG(10, ("ldb:acl_rename: %s\n", ldb_dn_get_linearized(req->op.rename.olddn)));
1299         if (dsdb_module_am_system(module) || as_system) {
1300                 return ldb_next_request(module, req);
1301         }
1302
1303         ldb = ldb_module_get_ctx(module);
1304
1305         tmp_ctx = talloc_new(req);
1306         if (tmp_ctx == NULL) {
1307                 return ldb_oom(ldb);
1308         }
1309
1310         oldparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.olddn);
1311         if (oldparent == NULL) {
1312                 return ldb_oom(ldb);
1313         }
1314         newparent = ldb_dn_get_parent(tmp_ctx, req->op.rename.newdn);
1315         if (newparent == NULL) {
1316                 return ldb_oom(ldb);
1317         }
1318
1319         /* Make sure we aren't renaming/moving a NC */
1320
1321         ret = dsdb_find_nc_root(ldb, req, req->op.rename.olddn, &nc_root);
1322         if (ret != LDB_SUCCESS) {
1323                 return ret;
1324         }
1325         if (ldb_dn_compare(nc_root, req->op.rename.olddn) == 0) {
1326                 talloc_free(nc_root);
1327                 DEBUG(10,("acl:renaming/moving a NC\n"));
1328                 /* Windows returns "ERR_UNWILLING_TO_PERFORM */
1329                 return ldb_module_done(req, NULL, NULL,
1330                                        LDB_ERR_UNWILLING_TO_PERFORM);
1331         }
1332         talloc_free(nc_root);
1333
1334         /* Look for the parent */
1335
1336         ret = dsdb_module_search_dn(module, tmp_ctx, &acl_res,
1337                                     req->op.rename.olddn, acl_attrs,
1338                                     DSDB_FLAG_NEXT_MODULE |
1339                                     DSDB_FLAG_AS_SYSTEM |
1340                                     DSDB_SEARCH_SHOW_RECYCLED, req);
1341         /* we sould be able to find the parent */
1342         if (ret != LDB_SUCCESS) {
1343                 DEBUG(10,("acl: failed to find object %s\n",
1344                           ldb_dn_get_linearized(req->op.rename.olddn)));
1345                 talloc_free(tmp_ctx);
1346                 return ret;
1347         }
1348
1349         schema = dsdb_get_schema(ldb, acl_res);
1350         if (!schema) {
1351                 talloc_free(tmp_ctx);
1352                 return ldb_operr(ldb);
1353         }
1354
1355         objectclass = dsdb_get_structural_oc_from_msg(schema, acl_res->msgs[0]);
1356         if (!objectclass) {
1357                 talloc_free(tmp_ctx);
1358                 return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR,
1359                                  "acl_modify: Error retrieving object class for GUID.");
1360         }
1361
1362         if (!insert_in_object_tree(tmp_ctx, &objectclass->schemaIDGUID, SEC_ADS_WRITE_PROP,
1363                                    &root, &new_node)) {
1364                 talloc_free(tmp_ctx);
1365                 return ldb_operr(ldb);
1366         }
1367
1368         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1369                                                           "name");
1370         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1371                                    &new_node, &new_node)) {
1372                 talloc_free(tmp_ctx);
1373                 return ldb_operr(ldb);
1374         }
1375
1376         rdn_name = ldb_dn_get_rdn_name(req->op.rename.olddn);
1377         if (rdn_name == NULL) {
1378                 talloc_free(tmp_ctx);
1379                 return ldb_operr(ldb);
1380         }
1381         guid = attribute_schemaid_guid_by_lDAPDisplayName(schema,
1382                                                           rdn_name);
1383         if (!insert_in_object_tree(tmp_ctx, guid, SEC_ADS_WRITE_PROP,
1384                                    &new_node, &new_node)) {
1385                 talloc_free(tmp_ctx);
1386                 return ldb_operr(ldb);
1387         };
1388
1389         ret = dsdb_get_sd_from_ldb_message(ldb, req, acl_res->msgs[0], &sd);
1390
1391         if (ret != LDB_SUCCESS) {
1392                 talloc_free(tmp_ctx);
1393                 return ldb_operr(ldb);
1394         }
1395         /* Theoretically we pass the check if the object has no sd */
1396         if (!sd) {
1397                 talloc_free(tmp_ctx);
1398                 return LDB_SUCCESS;
1399         }
1400         sid = samdb_result_dom_sid(req, acl_res->msgs[0], "objectSid");
1401         status = sec_access_check_ds(sd, acl_user_token(module),
1402                                      SEC_ADS_WRITE_PROP,
1403                                      &access_granted,
1404                                      root,
1405                                      sid);
1406
1407         if (!NT_STATUS_IS_OK(status)) {
1408                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1409                                        "Object %s has no wp on name\n",
1410                                        ldb_dn_get_linearized(req->op.rename.olddn));
1411                 dsdb_acl_debug(sd,
1412                           acl_user_token(module),
1413                           req->op.rename.olddn,
1414                           true,
1415                           10);
1416                 talloc_free(tmp_ctx);
1417                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1418         }
1419
1420         if (ldb_dn_compare(oldparent, newparent) == 0) {
1421                 /* regular rename, not move, nothing more to do */
1422                 talloc_free(tmp_ctx);
1423                 return ldb_next_request(module, req);
1424         }
1425
1426         /* new parent should have create child */
1427         root = NULL;
1428         new_node = NULL;
1429
1430         ret = dsdb_module_check_access_on_dn(module, req, newparent,
1431                                              SEC_ADS_CREATE_CHILD,
1432                                              &objectclass->schemaIDGUID, req);
1433         if (ret != LDB_SUCCESS) {
1434                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1435                                        "acl:access_denied renaming %s",
1436                                        ldb_dn_get_linearized(req->op.rename.olddn));
1437                 talloc_free(tmp_ctx);
1438                 return ret;
1439         }
1440         /* do we have delete object on the object? */
1441
1442         status = sec_access_check_ds(sd, acl_user_token(module),
1443                                      SEC_STD_DELETE,
1444                                      &access_granted,
1445                                      NULL,
1446                                      sid);
1447
1448         if (NT_STATUS_IS_OK(status)) {
1449                 talloc_free(tmp_ctx);
1450                 return ldb_next_request(module, req);
1451         }
1452         /* what about delete child on the current parent */
1453         ret = dsdb_module_check_access_on_dn(module, req, oldparent, SEC_ADS_DELETE_CHILD, NULL, req);
1454         if (ret != LDB_SUCCESS) {
1455                 ldb_asprintf_errstring(ldb_module_get_ctx(module),
1456                                        "acl:access_denied renaming %s", ldb_dn_get_linearized(req->op.rename.olddn));
1457                 talloc_free(tmp_ctx);
1458                 return ldb_module_done(req, NULL, NULL, ret);
1459         }
1460
1461         talloc_free(tmp_ctx);
1462
1463         return ldb_next_request(module, req);
1464 }
1465
1466 static int acl_search_update_confidential_attrs(struct acl_context *ac,
1467                                                 struct acl_private *data)
1468 {
1469         struct dsdb_attribute *a;
1470         uint32_t n = 0;
1471
1472         if (data->acl_search) {
1473                 /*
1474                  * If acl:search is activated, the acl_read module
1475                  * protects confidential attributes.
1476                  */
1477                 return LDB_SUCCESS;
1478         }
1479
1480         if ((ac->schema == data->cached_schema_ptr) &&
1481             (ac->schema->loaded_usn == data->cached_schema_loaded_usn) &&
1482             (ac->schema->metadata_usn == data->cached_schema_metadata_usn))
1483         {
1484                 return LDB_SUCCESS;
1485         }
1486
1487         data->cached_schema_ptr = NULL;
1488         data->cached_schema_loaded_usn = 0;
1489         data->cached_schema_metadata_usn = 0;
1490         TALLOC_FREE(data->confidential_attrs);
1491
1492         if (ac->schema == NULL) {
1493                 return LDB_SUCCESS;
1494         }
1495
1496         for (a = ac->schema->attributes; a; a = a->next) {
1497                 const char **attrs = data->confidential_attrs;
1498
1499                 if (!(a->searchFlags & SEARCH_FLAG_CONFIDENTIAL)) {
1500                         continue;
1501                 }
1502
1503                 attrs = talloc_realloc(data, attrs, const char *, n + 2);
1504                 if (attrs == NULL) {
1505                         TALLOC_FREE(data->confidential_attrs);
1506                         return ldb_module_oom(ac->module);
1507                 }
1508
1509                 attrs[n] = a->lDAPDisplayName;
1510                 attrs[n+1] = NULL;
1511                 n++;
1512
1513                 data->confidential_attrs = attrs;
1514         }
1515
1516         data->cached_schema_ptr = ac->schema;
1517         data->cached_schema_loaded_usn = ac->schema->loaded_usn;
1518         data->cached_schema_metadata_usn = ac->schema->metadata_usn;
1519
1520         return LDB_SUCCESS;
1521 }
1522
1523 static int acl_search_callback(struct ldb_request *req, struct ldb_reply *ares)
1524 {
1525         struct acl_context *ac;
1526         struct acl_private *data;
1527         struct ldb_result *acl_res;
1528         static const char *acl_attrs[] = {
1529                 "objectClass",
1530                 "nTSecurityDescriptor",
1531                 "objectSid",
1532                 NULL
1533         };
1534         int ret;
1535         unsigned int i;
1536
1537         ac = talloc_get_type(req->context, struct acl_context);
1538         data = talloc_get_type(ldb_module_get_private(ac->module), struct acl_private);
1539         if (!ares) {
1540                 return ldb_module_done(ac->req, NULL, NULL,
1541                                        LDB_ERR_OPERATIONS_ERROR);
1542         }
1543         if (ares->error != LDB_SUCCESS) {
1544                 return ldb_module_done(ac->req, ares->controls,
1545                                        ares->response, ares->error);
1546         }
1547
1548         switch (ares->type) {
1549         case LDB_REPLY_ENTRY:
1550                 if (ac->constructed_attrs) {
1551                         ret = dsdb_module_search_dn(ac->module, ac, &acl_res, ares->message->dn,
1552                                                     acl_attrs,
1553                                                     DSDB_FLAG_NEXT_MODULE |
1554                                                     DSDB_FLAG_AS_SYSTEM |
1555                                                     DSDB_SEARCH_SHOW_RECYCLED,
1556                                                     req);
1557                         if (ret != LDB_SUCCESS) {
1558                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1559                         }
1560                 }
1561
1562                 if (ac->allowedAttributes || ac->allowedAttributesEffective) {
1563                         ret = acl_allowedAttributes(ac->module, ac->schema,
1564                                                     acl_res->msgs[0],
1565                                                     ares->message, ac);
1566                         if (ret != LDB_SUCCESS) {
1567                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1568                         }
1569                 }
1570
1571                 if (ac->allowedChildClasses) {
1572                         ret = acl_childClasses(ac->module, ac->schema,
1573                                                acl_res->msgs[0],
1574                                                ares->message,
1575                                                "allowedChildClasses");
1576                         if (ret != LDB_SUCCESS) {
1577                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1578                         }
1579                 }
1580
1581                 if (ac->allowedChildClassesEffective) {
1582                         ret = acl_childClassesEffective(ac->module, ac->schema,
1583                                                         acl_res->msgs[0],
1584                                                         ares->message, ac);
1585                         if (ret != LDB_SUCCESS) {
1586                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1587                         }
1588                 }
1589
1590                 if (ac->sDRightsEffective) {
1591                         ret = acl_sDRightsEffective(ac->module,
1592                                                     acl_res->msgs[0],
1593                                                     ares->message, ac);
1594                         if (ret != LDB_SUCCESS) {
1595                                 return ldb_module_done(ac->req, NULL, NULL, ret);
1596                         }
1597                 }
1598
1599                 if (data == NULL) {
1600                         return ldb_module_send_entry(ac->req, ares->message,
1601                                                      ares->controls);
1602                 }
1603
1604                 if (ac->am_system) {
1605                         return ldb_module_send_entry(ac->req, ares->message,
1606                                                      ares->controls);
1607                 }
1608
1609                 if (data->password_attrs != NULL) {
1610                         for (i = 0; data->password_attrs[i]; i++) {
1611                                 if ((!ac->userPassword) &&
1612                                     (ldb_attr_cmp(data->password_attrs[i],
1613                                                   "userPassword") == 0))
1614                                 {
1615                                                 continue;
1616                                 }
1617
1618                                 ldb_msg_remove_attr(ares->message, data->password_attrs[i]);
1619                         }
1620                 }
1621
1622                 if (ac->am_administrator) {
1623                         return ldb_module_send_entry(ac->req, ares->message,
1624                                                      ares->controls);
1625                 }
1626
1627                 ret = acl_search_update_confidential_attrs(ac, data);
1628                 if (ret != LDB_SUCCESS) {
1629                         return ret;
1630                 }
1631
1632                 if (data->confidential_attrs != NULL) {
1633                         for (i = 0; data->confidential_attrs[i]; i++) {
1634                                 ldb_msg_remove_attr(ares->message,
1635                                                     data->confidential_attrs[i]);
1636                         }
1637                 }
1638
1639                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
1640
1641         case LDB_REPLY_REFERRAL:
1642                 return ldb_module_send_referral(ac->req, ares->referral);
1643
1644         case LDB_REPLY_DONE:
1645                 return ldb_module_done(ac->req, ares->controls,
1646                                        ares->response, LDB_SUCCESS);
1647
1648         }
1649         return LDB_SUCCESS;
1650 }
1651
1652 static int acl_search(struct ldb_module *module, struct ldb_request *req)
1653 {
1654         struct ldb_context *ldb;
1655         struct acl_context *ac;
1656         struct ldb_parse_tree *down_tree;
1657         struct ldb_request *down_req;
1658         struct acl_private *data;
1659         int ret;
1660         unsigned int i;
1661
1662         if (ldb_dn_is_special(req->op.search.base)) {
1663                 return ldb_next_request(module, req);
1664         }
1665
1666         ldb = ldb_module_get_ctx(module);
1667
1668         ac = talloc_zero(req, struct acl_context);
1669         if (ac == NULL) {
1670                 return ldb_oom(ldb);
1671         }
1672         data = talloc_get_type(ldb_module_get_private(module), struct acl_private);
1673
1674         ac->module = module;
1675         ac->req = req;
1676         ac->am_system = dsdb_module_am_system(module);
1677         ac->am_administrator = dsdb_module_am_administrator(module);
1678         ac->constructed_attrs = false;
1679         ac->modify_search = true;
1680         ac->allowedAttributes = ldb_attr_in_list(req->op.search.attrs, "allowedAttributes");
1681         ac->allowedAttributesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedAttributesEffective");
1682         ac->allowedChildClasses = ldb_attr_in_list(req->op.search.attrs, "allowedChildClasses");
1683         ac->allowedChildClassesEffective = ldb_attr_in_list(req->op.search.attrs, "allowedChildClassesEffective");
1684         ac->sDRightsEffective = ldb_attr_in_list(req->op.search.attrs, "sDRightsEffective");
1685         ac->userPassword = true;
1686         ac->schema = dsdb_get_schema(ldb, ac);
1687
1688         ac->constructed_attrs |= ac->allowedAttributes;
1689         ac->constructed_attrs |= ac->allowedChildClasses;
1690         ac->constructed_attrs |= ac->allowedChildClassesEffective;
1691         ac->constructed_attrs |= ac->allowedAttributesEffective;
1692         ac->constructed_attrs |= ac->sDRightsEffective;
1693
1694         if (data == NULL) {
1695                 ac->modify_search = false;
1696         }
1697         if (ac->am_system) {
1698                 ac->modify_search = false;
1699         }
1700
1701         if (!ac->constructed_attrs && !ac->modify_search) {
1702                 talloc_free(ac);
1703                 return ldb_next_request(module, req);
1704         }
1705
1706         if (!ac->am_system) {
1707                 ac->userPassword = dsdb_user_password_support(module, ac, req);
1708         }
1709
1710         ret = acl_search_update_confidential_attrs(ac, data);
1711         if (ret != LDB_SUCCESS) {
1712                 return ret;
1713         }
1714
1715         down_tree = ldb_parse_tree_copy_shallow(ac, req->op.search.tree);
1716         if (down_tree == NULL) {
1717                 return ldb_oom(ldb);
1718         }
1719
1720         if (!ac->am_system && data->password_attrs) {
1721                 for (i = 0; data->password_attrs[i]; i++) {
1722                         if ((!ac->userPassword) &&
1723                             (ldb_attr_cmp(data->password_attrs[i],
1724                                           "userPassword") == 0))
1725                         {
1726                                 continue;
1727                         }
1728
1729                         ldb_parse_tree_attr_replace(down_tree,
1730                                                     data->password_attrs[i],
1731                                                     "kludgeACLredactedattribute");
1732                 }
1733         }
1734
1735         if (!ac->am_system && !ac->am_administrator && data->confidential_attrs) {
1736                 for (i = 0; data->confidential_attrs[i]; i++) {
1737                         ldb_parse_tree_attr_replace(down_tree,
1738                                                     data->confidential_attrs[i],
1739                                                     "kludgeACLredactedattribute");
1740                 }
1741         }
1742
1743         ret = ldb_build_search_req_ex(&down_req,
1744                                       ldb, ac,
1745                                       req->op.search.base,
1746                                       req->op.search.scope,
1747                                       down_tree,
1748                                       req->op.search.attrs,
1749                                       req->controls,
1750                                       ac, acl_search_callback,
1751                                       req);
1752         LDB_REQ_SET_LOCATION(down_req);
1753         if (ret != LDB_SUCCESS) {
1754                 return ret;
1755         }
1756         /* perform the search */
1757         return ldb_next_request(module, down_req);
1758 }
1759
1760 static int acl_extended(struct ldb_module *module, struct ldb_request *req)
1761 {
1762         struct ldb_context *ldb = ldb_module_get_ctx(module);
1763         struct ldb_control *as_system = ldb_request_get_control(req, LDB_CONTROL_AS_SYSTEM_OID);
1764
1765         /* allow everybody to read the sequence number */
1766         if (strcmp(req->op.extended.oid,
1767                    LDB_EXTENDED_SEQUENCE_NUMBER) == 0) {
1768                 return ldb_next_request(module, req);
1769         }
1770
1771         if (dsdb_module_am_system(module) ||
1772             dsdb_module_am_administrator(module) || as_system) {
1773                 return ldb_next_request(module, req);
1774         } else {
1775                 ldb_asprintf_errstring(ldb,
1776                                        "acl_extended: "
1777                                        "attempted database modify not permitted. "
1778                                        "User %s is not SYSTEM or an administrator",
1779                                        acl_user_name(req, module));
1780                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
1781         }
1782 }
1783
1784 static const struct ldb_module_ops ldb_acl_module_ops = {
1785         .name              = "acl",
1786         .search            = acl_search,
1787         .add               = acl_add,
1788         .modify            = acl_modify,
1789         .del               = acl_delete,
1790         .rename            = acl_rename,
1791         .extended          = acl_extended,
1792         .init_context      = acl_module_init
1793 };
1794
1795 int ldb_acl_module_init(const char *version)
1796 {
1797         LDB_MODULE_CHECK_VERSION(version);
1798         return ldb_register_module(&ldb_acl_module_ops);
1799 }