source4/dsdb/samdb/ldb_modules/descriptor.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Simo Sorce  2006-2008
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2007
   6    Copyright (C) Nadezhda Ivanova  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: DS Security descriptor module
  26  *
  27  *  Description:
  28  *  - Calculate the security descriptor of a newly created object
  29  *  - Perform sd recalculation on a move operation
  30  *  - Handle sd modification invariants
  31  *
  32  *  Author: Nadezhda Ivanova
  33  */
  34
  35 #include "includes.h"
  36 #include <ldb_module.h>
  37 #include "util/dlinklist.h"
  38 #include "dsdb/samdb/samdb.h"
  39 #include "librpc/ndr/libndr.h"
  40 #include "librpc/gen_ndr/ndr_security.h"
  41 #include "libcli/security/security.h"
  42 #include "auth/auth.h"
  43 #include "param/param.h"
  44 #include "dsdb/samdb/ldb_modules/util.h"
  45
  46 struct descriptor_data {
  47         int _dummy;
  48 };
  49
  50 struct descriptor_context {
  51         struct ldb_module *module;
  52         struct ldb_request *req;
  53         struct ldb_message *msg;
  54         struct ldb_reply *search_res;
  55         struct ldb_reply *search_oc_res;
  56         struct ldb_val *parentsd_val;
  57         struct ldb_message_element *sd_element;
  58         struct ldb_val *sd_val;
  59         uint32_t sd_flags;
  60         int (*step_fn)(struct descriptor_context *);
  61 };
  62
  63 static struct dom_sid *get_default_ag(TALLOC_CTX *mem_ctx,
  64                                struct ldb_dn *dn,
  65                                struct security_token *token,
  66                                struct ldb_context *ldb)
  67 {
  68         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  69         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
  70         struct dom_sid *da_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_ADMINS);
  71         struct dom_sid *ea_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_ENTERPRISE_ADMINS);
  72         struct dom_sid *sa_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_SCHEMA_ADMINS);
  73         struct dom_sid *dag_sid;
  74         struct ldb_dn *nc_root;
  75         int ret;
  76
  77         ret = dsdb_find_nc_root(ldb, tmp_ctx, dn, &nc_root);
  78         if (ret != LDB_SUCCESS) {
  79                 talloc_free(tmp_ctx);
  80                 return NULL;
  81         }
  82
  83         if (ldb_dn_compare(nc_root, ldb_get_schema_basedn(ldb)) == 0) {
  84                 if (security_token_has_sid(token, sa_sid)) {
  85                         dag_sid = dom_sid_dup(mem_ctx, sa_sid);
  86                 } else if (security_token_has_sid(token, ea_sid)) {
  87                         dag_sid = dom_sid_dup(mem_ctx, ea_sid);
  88                 } else if (security_token_has_sid(token, da_sid)) {
  89                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
  90                 } else if (security_token_is_system(token)) {
  91                         dag_sid = dom_sid_dup(mem_ctx, sa_sid);
  92                 } else {
  93                         dag_sid = NULL;
  94                 }
  95         } else if (ldb_dn_compare(nc_root, ldb_get_config_basedn(ldb)) == 0) {
  96                 if (security_token_has_sid(token, ea_sid)) {
  97                         dag_sid = dom_sid_dup(mem_ctx, ea_sid);
  98                 } else if (security_token_has_sid(token, da_sid)) {
  99                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
 100                 } else if (security_token_is_system(token)) {
 101                         dag_sid = dom_sid_dup(mem_ctx, ea_sid);
 102                 } else {
 103                         dag_sid = NULL;
 104                 }
 105         } else if (ldb_dn_compare(nc_root, ldb_get_default_basedn(ldb)) == 0) {
 106                 if (security_token_has_sid(token, da_sid)) {
 107                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
 108                 } else if (security_token_has_sid(token, ea_sid)) {
 109                                 dag_sid = dom_sid_dup(mem_ctx, ea_sid);
 110                 } else if (security_token_is_system(token)) {
 111                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
 112                 } else {
 113                         dag_sid = NULL;
 114                 }
 115         } else {
 116                 dag_sid = NULL;
 117         }
 118
 119         talloc_free(tmp_ctx);
 120         return dag_sid;
 121 }
 122
 123 static struct security_descriptor *get_sd_unpacked(struct ldb_module *module, TALLOC_CTX *mem_ctx,
 124                                             const struct dsdb_class *objectclass)
 125 {
 126         struct ldb_context *ldb = ldb_module_get_ctx(module);
 127         struct security_descriptor *sd;
 128         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
 129
 130         if (!objectclass->defaultSecurityDescriptor || !domain_sid) {
 131                 return NULL;
 132         }
 133
 134         sd = sddl_decode(mem_ctx,
 135                          objectclass->defaultSecurityDescriptor,
 136                          domain_sid);
 137         return sd;
 138 }
 139
 140 static struct dom_sid *get_default_group(TALLOC_CTX *mem_ctx,
 141                                          struct ldb_context *ldb,
 142                                          struct dom_sid *dag)
 143 {
 144         if (dsdb_functional_level(ldb) >= DS_DOMAIN_FUNCTION_2008) {
 145                 return dag;
 146         }
 147
 148         return NULL;
 149 }
 150
 151 static struct security_descriptor *descr_handle_sd_flags(TALLOC_CTX *mem_ctx,
 152                                                          struct security_descriptor *new_sd,
 153                                                          struct security_descriptor *old_sd,
 154                                                          uint32_t sd_flags)
 155 {
 156         struct security_descriptor *final_sd;
 157         /* if there is no control or control == 0 modify everything */
 158         if (!sd_flags) {
 159                 return new_sd;
 160         }
 161
 162         final_sd = talloc_zero(mem_ctx, struct security_descriptor);
 163         final_sd->revision = SECURITY_DESCRIPTOR_REVISION_1;
 164         final_sd->type = SEC_DESC_SELF_RELATIVE;
 165
 166         if (sd_flags & (SECINFO_OWNER)) {
 167                 final_sd->owner_sid = talloc_memdup(mem_ctx, new_sd->owner_sid, sizeof(struct dom_sid));
 168                 final_sd->type |= new_sd->type & SEC_DESC_OWNER_DEFAULTED;
 169         }
 170         else if (old_sd) {
 171                 final_sd->owner_sid = talloc_memdup(mem_ctx, old_sd->owner_sid, sizeof(struct dom_sid));
 172                 final_sd->type |= old_sd->type & SEC_DESC_OWNER_DEFAULTED;
 173         }
 174
 175         if (sd_flags & (SECINFO_GROUP)) {
 176                 final_sd->group_sid = talloc_memdup(mem_ctx, new_sd->group_sid, sizeof(struct dom_sid));
 177                 final_sd->type |= new_sd->type & SEC_DESC_GROUP_DEFAULTED;
 178         }
 179         else if (old_sd) {
 180                 final_sd->group_sid = talloc_memdup(mem_ctx, old_sd->group_sid, sizeof(struct dom_sid));
 181                 final_sd->type |= old_sd->type & SEC_DESC_GROUP_DEFAULTED;
 182         }
 183
 184         if (sd_flags & (SECINFO_SACL)) {
 185                 final_sd->sacl = security_acl_dup(mem_ctx,new_sd->sacl);
 186                 final_sd->type |= new_sd->type & (SEC_DESC_SACL_PRESENT |
 187                         SEC_DESC_SACL_DEFAULTED|SEC_DESC_SACL_AUTO_INHERIT_REQ |
 188                         SEC_DESC_SACL_AUTO_INHERITED|SEC_DESC_SACL_PROTECTED |
 189                         SEC_DESC_SERVER_SECURITY);
 190         }
 191         else if (old_sd && old_sd->sacl) {
 192                 final_sd->sacl = security_acl_dup(mem_ctx,old_sd->sacl);
 193                 final_sd->type |= old_sd->type & (SEC_DESC_SACL_PRESENT |
 194                         SEC_DESC_SACL_DEFAULTED|SEC_DESC_SACL_AUTO_INHERIT_REQ |
 195                         SEC_DESC_SACL_AUTO_INHERITED|SEC_DESC_SACL_PROTECTED |
 196                         SEC_DESC_SERVER_SECURITY);
 197         }
 198
 199         if (sd_flags & (SECINFO_DACL)) {
 200                 final_sd->dacl = security_acl_dup(mem_ctx,new_sd->dacl);
 201                 final_sd->type |= new_sd->type & (SEC_DESC_DACL_PRESENT |
 202                         SEC_DESC_DACL_DEFAULTED|SEC_DESC_DACL_AUTO_INHERIT_REQ |
 203                         SEC_DESC_DACL_AUTO_INHERITED|SEC_DESC_DACL_PROTECTED |
 204                         SEC_DESC_DACL_TRUSTED);
 205         }
 206         else if (old_sd && old_sd->dacl) {
 207                 final_sd->dacl = security_acl_dup(mem_ctx,old_sd->dacl);
 208                 final_sd->type |= old_sd->type & (SEC_DESC_DACL_PRESENT |
 209                         SEC_DESC_DACL_DEFAULTED|SEC_DESC_DACL_AUTO_INHERIT_REQ |
 210                         SEC_DESC_DACL_AUTO_INHERITED|SEC_DESC_DACL_PROTECTED |
 211                         SEC_DESC_DACL_TRUSTED);
 212         }
 213         /* not so sure about this */
 214         final_sd->type |= new_sd->type & SEC_DESC_RM_CONTROL_VALID;
 215         return final_sd;
 216 }
 217
 218 static DATA_BLOB *get_new_descriptor(struct ldb_module *module,
 219                                      struct ldb_dn *dn,
 220                                      TALLOC_CTX *mem_ctx,
 221                                      const struct dsdb_class *objectclass,
 222                                      const struct ldb_val *parent,
 223                                      const struct ldb_val *object,
 224                                      const struct ldb_val *old_sd,
 225                                      uint32_t sd_flags)
 226 {
 227         struct security_descriptor *user_descriptor = NULL, *parent_descriptor = NULL;
 228         struct security_descriptor *old_descriptor = NULL;
 229         struct security_descriptor *new_sd, *final_sd;
 230         DATA_BLOB *linear_sd;
 231         enum ndr_err_code ndr_err;
 232         struct ldb_context *ldb = ldb_module_get_ctx(module);
 233         struct auth_session_info *session_info
 234                 = ldb_get_opaque(ldb, "sessionInfo");
 235         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
 236         char *sddl_sd;
 237         struct dom_sid *default_owner;
 238         struct dom_sid *default_group;
 239
 240         if (object) {
 241                 user_descriptor = talloc(mem_ctx, struct security_descriptor);
 242                 if (!user_descriptor) {
 243                         return NULL;
 244                 }
 245                 ndr_err = ndr_pull_struct_blob(object, user_descriptor,
 246                                                user_descriptor,
 247                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 248
 249                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 250                         talloc_free(user_descriptor);
 251                         return NULL;
 252                 }
 253         } else {
 254                 user_descriptor = get_sd_unpacked(module, mem_ctx, objectclass);
 255         }
 256
 257         if (old_sd) {
 258                 old_descriptor = talloc(mem_ctx, struct security_descriptor);
 259                 if (!old_descriptor) {
 260                         return NULL;
 261                 }
 262                 ndr_err = ndr_pull_struct_blob(old_sd, old_descriptor,
 263                                                old_descriptor,
 264                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 265
 266                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 267                         talloc_free(old_descriptor);
 268                         return NULL;
 269                 }
 270         }
 271
 272         if (parent) {
 273                 parent_descriptor = talloc(mem_ctx, struct security_descriptor);
 274                 if (!parent_descriptor) {
 275                         return NULL;
 276                 }
 277                 ndr_err = ndr_pull_struct_blob(parent, parent_descriptor,
 278                                                parent_descriptor,
 279                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 280
 281                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 282                         talloc_free(parent_descriptor);
 283                         return NULL;
 284                 }
 285         }
 286
 287         default_owner = get_default_ag(mem_ctx, dn,
 288                                        session_info->security_token, ldb);
 289         default_group = get_default_group(mem_ctx, ldb, default_owner);
 290         new_sd = create_security_descriptor(mem_ctx, parent_descriptor, user_descriptor, true,
 291                                             NULL, SEC_DACL_AUTO_INHERIT|SEC_SACL_AUTO_INHERIT,
 292                                             session_info->security_token,
 293                                             default_owner, default_group,
 294                                             map_generic_rights_ds);
 295         if (!new_sd) {
 296                 return NULL;
 297         }
 298         final_sd = descr_handle_sd_flags(mem_ctx, new_sd, old_descriptor, sd_flags);
 299
 300         if (!final_sd) {
 301                 return NULL;
 302         }
 303
 304         if (final_sd->dacl) {
 305                 final_sd->dacl->revision = SECURITY_ACL_REVISION_ADS;
 306         }
 307         if (final_sd->sacl) {
 308                 final_sd->sacl->revision = SECURITY_ACL_REVISION_ADS;
 309         }
 310
 311         sddl_sd = sddl_encode(mem_ctx, final_sd, domain_sid);
 312         DEBUG(10, ("Object %s created with desriptor %s\n\n", ldb_dn_get_linearized(dn), sddl_sd));
 313
 314         linear_sd = talloc(mem_ctx, DATA_BLOB);
 315         if (!linear_sd) {
 316                 return NULL;
 317         }
 318
 319         ndr_err = ndr_push_struct_blob(linear_sd, mem_ctx,
 320                                        final_sd,
 321                                        (ndr_push_flags_fn_t)ndr_push_security_descriptor);
 322         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 323                 return NULL;
 324         }
 325
 326         return linear_sd;
 327 }
 328
 329 static DATA_BLOB *descr_get_descriptor_to_show(struct ldb_module *module,
 330                                                TALLOC_CTX *mem_ctx,
 331                                                struct ldb_val *sd,
 332                                                uint32_t sd_flags)
 333 {
 334         struct security_descriptor *old_sd, *final_sd;
 335         DATA_BLOB *linear_sd;
 336         enum ndr_err_code ndr_err;
 337
 338         old_sd = talloc(mem_ctx, struct security_descriptor);
 339         if (!old_sd) {
 340                 return NULL;
 341         }
 342         ndr_err = ndr_pull_struct_blob(sd, old_sd,
 343                                        old_sd,
 344                                        (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 345
 346         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 347                 talloc_free(old_sd);
 348                 return NULL;
 349         }
 350
 351         final_sd = descr_handle_sd_flags(mem_ctx, old_sd, NULL, sd_flags);
 352
 353         if (!final_sd) {
 354                 return NULL;
 355         }
 356
 357         linear_sd = talloc(mem_ctx, DATA_BLOB);
 358         if (!linear_sd) {
 359                 return NULL;
 360         }
 361
 362         ndr_err = ndr_push_struct_blob(linear_sd, mem_ctx,
 363                                        final_sd,
 364                                        (ndr_push_flags_fn_t)ndr_push_security_descriptor);
 365         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 366                 return NULL;
 367         }
 368
 369         return linear_sd;
 370 }
 371
 372 static struct descriptor_context *descriptor_init_context(struct ldb_module *module,
 373                                                           struct ldb_request *req)
 374 {
 375         struct ldb_context *ldb;
 376         struct descriptor_context *ac;
 377
 378         ldb = ldb_module_get_ctx(module);
 379
 380         ac = talloc_zero(req, struct descriptor_context);
 381         if (ac == NULL) {
 382                 ldb_set_errstring(ldb, "Out of Memory");
 383                 return NULL;
 384         }
 385
 386         ac->module = module;
 387         ac->req = req;
 388         return ac;
 389 }
 390
 391 static int descriptor_search_callback(struct ldb_request *req, struct ldb_reply *ares)
 392 {
 393         struct descriptor_context *ac;
 394         struct ldb_val *sd_val = NULL;
 395         struct ldb_message_element *sd_el;
 396         DATA_BLOB *show_sd;
 397         int ret;
 398
 399         ac = talloc_get_type(req->context, struct descriptor_context);
 400
 401         if (!ares) {
 402                 ret = LDB_ERR_OPERATIONS_ERROR;
 403                 goto fail;
 404         }
 405         if (ares->error != LDB_SUCCESS) {
 406                 return ldb_module_done(ac->req, ares->controls,
 407                                         ares->response, ares->error);
 408         }
 409
 410         switch (ares->type) {
 411         case LDB_REPLY_ENTRY:
 412                 sd_el = ldb_msg_find_element(ares->message, "nTSecurityDescriptor");
 413                 if (sd_el) {
 414                         sd_val = sd_el->values;
 415                 }
 416
 417                 if (sd_val) {
 418                         show_sd = descr_get_descriptor_to_show(ac->module, ac->req,
 419                                                                sd_val, ac->sd_flags);
 420                         if (!show_sd) {
 421                                 ret = LDB_ERR_OPERATIONS_ERROR;
 422                                 goto fail;
 423                         }
 424                         ldb_msg_remove_attr(ares->message, "nTSecurityDescriptor");
 425                         ret = ldb_msg_add_steal_value(ares->message, "nTSecurityDescriptor", show_sd);
 426                         if (ret != LDB_SUCCESS) {
 427                                 goto fail;
 428                         }
 429                 }
 430                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
 431
 432         case LDB_REPLY_REFERRAL:
 433                 return ldb_module_send_referral(ac->req, ares->referral);
 434
 435         case LDB_REPLY_DONE:
 436                 return ldb_module_done(ac->req, ares->controls,
 437                                         ares->response, ares->error);
 438         }
 439
 440 fail:
 441         talloc_free(ares);
 442         return ldb_module_done(ac->req, NULL, NULL, ret);
 443 }
 444
 445 static int descriptor_add(struct ldb_module *module, struct ldb_request *req)
 446 {
 447         struct ldb_context *ldb;
 448         struct ldb_request *add_req;
 449         struct ldb_message *msg;
 450         struct ldb_result *parent_res;
 451         const struct ldb_val *parent_sd = NULL;
 452         const struct ldb_val *user_sd;
 453         struct ldb_dn *parent_dn, *dn, *nc_root;
 454         struct ldb_message_element *objectclass_element, *sd_element;
 455         int ret;
 456         const struct dsdb_schema *schema;
 457         DATA_BLOB *sd;
 458         const struct dsdb_class *objectclass;
 459         static const char * const parent_attrs[] = { "nTSecurityDescriptor", NULL };
 460         uint32_t instanceType;
 461         bool isNC = false;
 462         uint32_t sd_flags = dsdb_request_sd_flags(req, NULL);
 463
 464         ldb = ldb_module_get_ctx(module);
 465         dn = req->op.add.message->dn;
 466         user_sd = ldb_msg_find_ldb_val(req->op.add.message, "nTSecurityDescriptor");
 467         sd_element = ldb_msg_find_element(req->op.add.message, "nTSecurityDescriptor");
 468         /* nTSecurityDescriptor without a value is an error, letting through so it is handled */
 469         if (user_sd == NULL && sd_element) {
 470                 return ldb_next_request(module, req);
 471         }
 472
 473         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: %s\n", ldb_dn_get_linearized(dn));
 474
 475         /* do not manipulate our control entries */
 476         if (ldb_dn_is_special(dn)) {
 477                 return ldb_next_request(module, req);
 478         }
 479
 480         instanceType = ldb_msg_find_attr_as_uint(req->op.add.message, "instanceType", 0);
 481
 482         if (instanceType & INSTANCE_TYPE_IS_NC_HEAD) {
 483                 isNC = true;
 484         }
 485
 486         if (!isNC) {
 487                 ret = dsdb_find_nc_root(ldb, req, dn, &nc_root);
 488                 if (ret != LDB_SUCCESS) {
 489                         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: Could not find NC root for %s\n",
 490                                 ldb_dn_get_linearized(dn));
 491                         return ret;
 492                 }
 493
 494                 if (ldb_dn_compare(dn, nc_root) == 0) {
 495                         DEBUG(0, ("Found DN %s being a NC by the old method\n", ldb_dn_get_linearized(dn)));
 496                         isNC = true;
 497                 }
 498         }
 499
 500         if (isNC) {
 501                 DEBUG(2, ("DN: %s is a NC\n", ldb_dn_get_linearized(dn)));
 502         }
 503         if (!isNC) {
 504                 /* if the object has a parent, retrieve its SD to
 505                  * use for calculation. Unfortunately we do not yet have
 506                  * instanceType, so we use dsdb_find_nc_root. */
 507
 508                 parent_dn = ldb_dn_get_parent(req, dn);
 509                 if (parent_dn == NULL) {
 510                         return ldb_oom(ldb);
 511                 }
 512
 513                 /* we aren't any NC */
 514                 ret = dsdb_module_search_dn(module, req, &parent_res, parent_dn,
 515                                             parent_attrs,
 516                                             DSDB_FLAG_NEXT_MODULE |
 517                                             DSDB_FLAG_AS_SYSTEM |
 518                                             DSDB_SEARCH_SHOW_RECYCLED,
 519                                             req);
 520                 if (ret != LDB_SUCCESS) {
 521                         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: Could not find SD for %s\n",
 522                                   ldb_dn_get_linearized(parent_dn));
 523                         return ret;
 524                 }
 525                 if (parent_res->count != 1) {
 526                         return ldb_operr(ldb);
 527                 }
 528                 parent_sd = ldb_msg_find_ldb_val(parent_res->msgs[0], "nTSecurityDescriptor");
 529         }
 530
 531         schema = dsdb_get_schema(ldb, req);
 532
 533         objectclass_element = ldb_msg_find_element(req->op.add.message, "objectClass");
 534         if (objectclass_element == NULL) {
 535                 return ldb_operr(ldb);
 536         }
 537
 538         objectclass = dsdb_get_last_structural_class(schema,
 539                                                      objectclass_element);
 540         if (objectclass == NULL) {
 541                 return ldb_operr(ldb);
 542         }
 543
 544         /*
 545          * The SD_FLAG control is ignored on add
 546          * and we default to all bits set.
 547          */
 548         sd_flags = 0xF;
 549
 550         sd = get_new_descriptor(module, dn, req,
 551                                 objectclass, parent_sd,
 552                                 user_sd, NULL, sd_flags);
 553         msg = ldb_msg_copy_shallow(req, req->op.add.message);
 554         if (sd != NULL) {
 555                 if (sd_element != NULL) {
 556                         sd_element->values[0] = *sd;
 557                 } else {
 558                         ret = ldb_msg_add_steal_value(msg,
 559                                                       "nTSecurityDescriptor",
 560                                                       sd);
 561                         if (ret != LDB_SUCCESS) {
 562                                 return ret;
 563                         }
 564                 }
 565         }
 566
 567         ret = ldb_build_add_req(&add_req, ldb, req,
 568                                 msg,
 569                                 req->controls,
 570                                 req, dsdb_next_callback,
 571                                 req);
 572         LDB_REQ_SET_LOCATION(add_req);
 573         if (ret != LDB_SUCCESS) {
 574                 return ldb_error(ldb, ret,
 575                                  "descriptor_add: Error creating new add request.");
 576         }
 577
 578         return ldb_next_request(module, add_req);
 579 }
 580
 581 static int descriptor_modify(struct ldb_module *module, struct ldb_request *req)
 582 {
 583         struct ldb_context *ldb;
 584         struct ldb_control *sd_recalculate_control;
 585         struct ldb_request *mod_req;
 586         struct ldb_message *msg;
 587         struct ldb_result *current_res, *parent_res;
 588         const struct ldb_val *old_sd = NULL;
 589         const struct ldb_val *parent_sd = NULL;
 590         const struct ldb_val *user_sd;
 591         struct ldb_dn *parent_dn, *dn;
 592         struct ldb_message_element *objectclass_element;
 593         int ret;
 594         uint32_t instanceType;
 595         uint32_t sd_flags = dsdb_request_sd_flags(req, NULL);
 596         const struct dsdb_schema *schema;
 597         DATA_BLOB *sd;
 598         const struct dsdb_class *objectclass;
 599         static const char * const parent_attrs[] = { "nTSecurityDescriptor", NULL };
 600         static const char * const current_attrs[] = { "nTSecurityDescriptor",
 601                                                       "instanceType",
 602                                                       "objectClass", NULL };
 603         ldb = ldb_module_get_ctx(module);
 604         dn = req->op.mod.message->dn;
 605         user_sd = ldb_msg_find_ldb_val(req->op.mod.message, "nTSecurityDescriptor");
 606         /* This control forces the recalculation of the SD also when
 607          * no modification is performed. */
 608         sd_recalculate_control = ldb_request_get_control(req,
 609                                              LDB_CONTROL_RECALCULATE_SD_OID);
 610         if (!user_sd && !sd_recalculate_control) {
 611                 return ldb_next_request(module, req);
 612         }
 613
 614         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_modify: %s\n", ldb_dn_get_linearized(dn));
 615
 616         /* do not manipulate our control entries */
 617         if (ldb_dn_is_special(dn)) {
 618                 return ldb_next_request(module, req);
 619         }
 620
 621         ret = dsdb_module_search_dn(module, req, &current_res, dn,
 622                                     current_attrs,
 623                                     DSDB_FLAG_NEXT_MODULE |
 624                                     DSDB_FLAG_AS_SYSTEM |
 625                                     DSDB_SEARCH_SHOW_RECYCLED,
 626                                     req);
 627         if (ret != LDB_SUCCESS) {
 628                 ldb_debug(ldb, LDB_DEBUG_ERROR,"descriptor_modify: Could not find %s\n",
 629                           ldb_dn_get_linearized(dn));
 630                 return ret;
 631         }
 632
 633         instanceType = ldb_msg_find_attr_as_uint(current_res->msgs[0],
 634                                                  "instanceType", 0);
 635         /* if the object has a parent, retrieve its SD to
 636          * use for calculation */
 637         if (!ldb_dn_is_null(current_res->msgs[0]->dn) &&
 638             !(instanceType & INSTANCE_TYPE_IS_NC_HEAD)) {
 639                 parent_dn = ldb_dn_get_parent(req, dn);
 640                 if (parent_dn == NULL) {
 641                         return ldb_oom(ldb);
 642                 }
 643                 ret = dsdb_module_search_dn(module, req, &parent_res, parent_dn,
 644                                             parent_attrs,
 645                                             DSDB_FLAG_NEXT_MODULE |
 646                                             DSDB_FLAG_AS_SYSTEM |
 647                                             DSDB_SEARCH_SHOW_RECYCLED,
 648                                             req);
 649                 if (ret != LDB_SUCCESS) {
 650                         ldb_debug(ldb, LDB_DEBUG_ERROR, "descriptor_modify: Could not find SD for %s\n",
 651                                   ldb_dn_get_linearized(parent_dn));
 652                         return ret;
 653                 }
 654                 if (parent_res->count != 1) {
 655                         return ldb_operr(ldb);
 656                 }
 657                 parent_sd = ldb_msg_find_ldb_val(parent_res->msgs[0], "nTSecurityDescriptor");
 658         }
 659
 660         schema = dsdb_get_schema(ldb, req);
 661
 662         objectclass_element = ldb_msg_find_element(current_res->msgs[0], "objectClass");
 663         if (objectclass_element == NULL) {
 664                 return ldb_operr(ldb);
 665         }
 666
 667         objectclass = dsdb_get_last_structural_class(schema,
 668                                                      objectclass_element);
 669         if (objectclass == NULL) {
 670                 return ldb_operr(ldb);
 671         }
 672
 673         old_sd = ldb_msg_find_ldb_val(current_res->msgs[0], "nTSecurityDescriptor");
 674
 675         sd = get_new_descriptor(module, dn, req,
 676                                 objectclass, parent_sd,
 677                                 user_sd, old_sd, sd_flags);
 678         msg = ldb_msg_copy_shallow(req, req->op.mod.message);
 679         if (sd != NULL) {
 680                 struct ldb_message_element *sd_element;
 681                 if (user_sd != NULL) {
 682                         sd_element = ldb_msg_find_element(msg,
 683                                                           "nTSecurityDescriptor");
 684                         sd_element->values[0] = *sd;
 685                 } else if (sd_recalculate_control != NULL) {
 686                         /* In this branch we really do force the recalculation
 687                          * of the SD */
 688                         ldb_msg_remove_attr(msg, "nTSecurityDescriptor");
 689
 690                         ret = ldb_msg_add_steal_value(msg,
 691                                                       "nTSecurityDescriptor",
 692                                                       sd);
 693                         if (ret != LDB_SUCCESS) {
 694                                 return ldb_error(ldb, ret,
 695                                          "descriptor_modify: Could not replace SD value in message.");
 696                         }
 697                         sd_element = ldb_msg_find_element(msg,
 698                                                           "nTSecurityDescriptor");
 699                         sd_element->flags = LDB_FLAG_MOD_REPLACE;
 700                 }
 701         }
 702
 703         /* mark the controls as non-critical since we've handled them */
 704         if (sd_recalculate_control != NULL) {
 705                 sd_recalculate_control->critical = 0;
 706         }
 707
 708         ret = ldb_build_mod_req(&mod_req, ldb, req,
 709                                 msg,
 710                                 req->controls,
 711                                 req,
 712                                 dsdb_next_callback,
 713                                 req);
 714         LDB_REQ_SET_LOCATION(mod_req);
 715         if (ret != LDB_SUCCESS) {
 716                 return ret;
 717         }
 718
 719         return ldb_next_request(module, mod_req);
 720 }
 721
 722 static int descriptor_search(struct ldb_module *module, struct ldb_request *req)
 723 {
 724         int ret;
 725         struct ldb_context *ldb;
 726         struct ldb_request *down_req;
 727         struct descriptor_context *ac;
 728         bool explicit_sd_flags = false;
 729         uint32_t sd_flags = dsdb_request_sd_flags(req, &explicit_sd_flags);
 730         bool show_sd = explicit_sd_flags;
 731
 732         if (!show_sd &&
 733             ldb_attr_in_list(req->op.search.attrs, "nTSecurityDescriptor"))
 734         {
 735                 show_sd = true;
 736         }
 737
 738         if (!show_sd) {
 739                 return ldb_next_request(module, req);
 740         }
 741
 742         ldb = ldb_module_get_ctx(module);
 743         ac = descriptor_init_context(module, req);
 744         if (ac == NULL) {
 745                 return ldb_operr(ldb);
 746         }
 747         ac->sd_flags = sd_flags;
 748
 749         ret = ldb_build_search_req_ex(&down_req, ldb, ac,
 750                                       req->op.search.base,
 751                                       req->op.search.scope,
 752                                       req->op.search.tree,
 753                                       req->op.search.attrs,
 754                                       req->controls,
 755                                       ac, descriptor_search_callback,
 756                                       ac->req);
 757         LDB_REQ_SET_LOCATION(down_req);
 758         if (ret != LDB_SUCCESS) {
 759                 return ret;
 760         }
 761
 762         return ldb_next_request(ac->module, down_req);
 763 }
 764 /* TODO */
 765 static int descriptor_rename(struct ldb_module *module, struct ldb_request *req)
 766 {
 767         struct ldb_context *ldb = ldb_module_get_ctx(module);
 768         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_rename: %s\n", ldb_dn_get_linearized(req->op.rename.olddn));
 769
 770         /* do not manipulate our control entries */
 771         if (ldb_dn_is_special(req->op.rename.olddn)) {
 772                 return ldb_next_request(module, req);
 773         }
 774
 775         return ldb_next_request(module, req);
 776 }
 777
 778 static int descriptor_init(struct ldb_module *module)
 779 {
 780         int ret = ldb_mod_register_control(module, LDB_CONTROL_SD_FLAGS_OID);
 781         struct ldb_context *ldb = ldb_module_get_ctx(module);
 782         if (ret != LDB_SUCCESS) {
 783                 ldb_debug(ldb, LDB_DEBUG_ERROR,
 784                         "descriptor: Unable to register control with rootdse!\n");
 785                 return ldb_operr(ldb);
 786         }
 787         return ldb_next_init(module);
 788 }
 789
 790
 791 static const struct ldb_module_ops ldb_descriptor_module_ops = {
 792         .name          = "descriptor",
 793         .search        = descriptor_search,
 794         .add           = descriptor_add,
 795         .modify        = descriptor_modify,
 796         .rename        = descriptor_rename,
 797         .init_context  = descriptor_init
 798 };
 799
 800 int ldb_descriptor_module_init(const char *version)
 801 {
 802         LDB_MODULE_CHECK_VERSION(version);
 803         return ldb_register_module(&ldb_descriptor_module_ops);
 804 }