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         int (*step_fn)(struct descriptor_context *);
  60 };
  61
  62 static struct dom_sid *get_default_ag(TALLOC_CTX *mem_ctx,
  63                                struct ldb_dn *dn,
  64                                struct security_token *token,
  65                                struct ldb_context *ldb)
  66 {
  67         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  68         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
  69         struct dom_sid *da_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_ADMINS);
  70         struct dom_sid *ea_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_ENTERPRISE_ADMINS);
  71         struct dom_sid *sa_sid = dom_sid_add_rid(tmp_ctx, domain_sid, DOMAIN_RID_SCHEMA_ADMINS);
  72         struct dom_sid *dag_sid;
  73         struct ldb_dn *nc_root;
  74         int ret;
  75
  76         ret = dsdb_find_nc_root(ldb, tmp_ctx, dn, &nc_root);
  77         if (ret != LDB_SUCCESS) {
  78                 talloc_free(tmp_ctx);
  79                 return NULL;
  80         }
  81
  82         if (ldb_dn_compare(nc_root, ldb_get_schema_basedn(ldb)) == 0) {
  83                 if (security_token_has_sid(token, sa_sid)) {
  84                         dag_sid = dom_sid_dup(mem_ctx, sa_sid);
  85                 } else if (security_token_has_sid(token, ea_sid)) {
  86                         dag_sid = dom_sid_dup(mem_ctx, ea_sid);
  87                 } else if (security_token_has_sid(token, da_sid)) {
  88                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
  89                 } else {
  90                         dag_sid = NULL;
  91                 }
  92         } else if (ldb_dn_compare(nc_root, ldb_get_config_basedn(ldb)) == 0) {
  93                 if (security_token_has_sid(token, ea_sid)) {
  94                         dag_sid = dom_sid_dup(mem_ctx, ea_sid);
  95                 } else if (security_token_has_sid(token, da_sid)) {
  96                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
  97                 } else {
  98                         dag_sid = NULL;
  99                 }
 100         } else if (ldb_dn_compare(nc_root, ldb_get_default_basedn(ldb)) == 0) {
 101                 if (security_token_has_sid(token, da_sid)) {
 102                         dag_sid = dom_sid_dup(mem_ctx, da_sid);
 103                 } else if (security_token_has_sid(token, ea_sid)) {
 104                                 dag_sid = dom_sid_dup(mem_ctx, ea_sid);
 105                 } else {
 106                         dag_sid = NULL;
 107                 }
 108         } else {
 109                 dag_sid = NULL;
 110         }
 111
 112         talloc_free(tmp_ctx);
 113         return dag_sid;
 114 }
 115
 116 static struct security_descriptor *get_sd_unpacked(struct ldb_module *module, TALLOC_CTX *mem_ctx,
 117                                             const struct dsdb_class *objectclass)
 118 {
 119         struct ldb_context *ldb = ldb_module_get_ctx(module);
 120         struct security_descriptor *sd;
 121         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
 122
 123         if (!objectclass->defaultSecurityDescriptor || !domain_sid) {
 124                 return NULL;
 125         }
 126
 127         sd = sddl_decode(mem_ctx,
 128                          objectclass->defaultSecurityDescriptor,
 129                          domain_sid);
 130         return sd;
 131 }
 132
 133 static struct dom_sid *get_default_group(TALLOC_CTX *mem_ctx,
 134                                          struct ldb_context *ldb,
 135                                          struct dom_sid *dag)
 136 {
 137         if (dsdb_functional_level(ldb) >= DS_DOMAIN_FUNCTION_2008) {
 138                 return dag;
 139         }
 140
 141         return NULL;
 142 }
 143
 144 static struct security_descriptor *descr_handle_sd_flags(TALLOC_CTX *mem_ctx,
 145                                                          struct security_descriptor *new_sd,
 146                                                          struct security_descriptor *old_sd,
 147                                                          uint32_t sd_flags)
 148 {
 149         struct security_descriptor *final_sd;
 150         /* if there is no control or control == 0 modify everything */
 151         if (!sd_flags) {
 152                 return new_sd;
 153         }
 154
 155         final_sd = talloc_zero(mem_ctx, struct security_descriptor);
 156         final_sd->revision = SECURITY_DESCRIPTOR_REVISION_1;
 157         final_sd->type = SEC_DESC_SELF_RELATIVE;
 158
 159         if (sd_flags & (SECINFO_OWNER)) {
 160                 final_sd->owner_sid = talloc_memdup(mem_ctx, new_sd->owner_sid, sizeof(struct dom_sid));
 161                 final_sd->type |= new_sd->type & SEC_DESC_OWNER_DEFAULTED;
 162         }
 163         else if (old_sd) {
 164                 final_sd->owner_sid = talloc_memdup(mem_ctx, old_sd->owner_sid, sizeof(struct dom_sid));
 165                 final_sd->type |= old_sd->type & SEC_DESC_OWNER_DEFAULTED;
 166         }
 167
 168         if (sd_flags & (SECINFO_GROUP)) {
 169                 final_sd->group_sid = talloc_memdup(mem_ctx, new_sd->group_sid, sizeof(struct dom_sid));
 170                 final_sd->type |= new_sd->type & SEC_DESC_GROUP_DEFAULTED;
 171         }
 172         else if (old_sd) {
 173                 final_sd->group_sid = talloc_memdup(mem_ctx, old_sd->group_sid, sizeof(struct dom_sid));
 174                 final_sd->type |= old_sd->type & SEC_DESC_GROUP_DEFAULTED;
 175         }
 176
 177         if (sd_flags & (SECINFO_SACL)) {
 178                 final_sd->sacl = security_acl_dup(mem_ctx,new_sd->sacl);
 179                 final_sd->type |= new_sd->type & (SEC_DESC_SACL_PRESENT |
 180                         SEC_DESC_SACL_DEFAULTED|SEC_DESC_SACL_AUTO_INHERIT_REQ |
 181                         SEC_DESC_SACL_AUTO_INHERITED|SEC_DESC_SACL_PROTECTED |
 182                         SEC_DESC_SERVER_SECURITY);
 183         }
 184         else if (old_sd && old_sd->sacl) {
 185                 final_sd->sacl = security_acl_dup(mem_ctx,old_sd->sacl);
 186                 final_sd->type |= old_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
 192         if (sd_flags & (SECINFO_DACL)) {
 193                 final_sd->dacl = security_acl_dup(mem_ctx,new_sd->dacl);
 194                 final_sd->type |= new_sd->type & (SEC_DESC_DACL_PRESENT |
 195                         SEC_DESC_DACL_DEFAULTED|SEC_DESC_DACL_AUTO_INHERIT_REQ |
 196                         SEC_DESC_DACL_AUTO_INHERITED|SEC_DESC_DACL_PROTECTED |
 197                         SEC_DESC_DACL_TRUSTED);
 198         }
 199         else if (old_sd && old_sd->dacl) {
 200                 final_sd->dacl = security_acl_dup(mem_ctx,old_sd->dacl);
 201                 final_sd->type |= old_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         /* not so sure about this */
 207         final_sd->type |= new_sd->type & SEC_DESC_RM_CONTROL_VALID;
 208         return final_sd;
 209 }
 210
 211 static DATA_BLOB *get_new_descriptor(struct ldb_module *module,
 212                                      struct ldb_dn *dn,
 213                                      TALLOC_CTX *mem_ctx,
 214                                      const struct dsdb_class *objectclass,
 215                                      const struct ldb_val *parent,
 216                                      const struct ldb_val *object,
 217                                      const struct ldb_val *old_sd,
 218                                      uint32_t sd_flags)
 219 {
 220         struct security_descriptor *user_descriptor = NULL, *parent_descriptor = NULL;
 221         struct security_descriptor *old_descriptor = NULL;
 222         struct security_descriptor *new_sd, *final_sd;
 223         DATA_BLOB *linear_sd;
 224         enum ndr_err_code ndr_err;
 225         struct ldb_context *ldb = ldb_module_get_ctx(module);
 226         struct auth_session_info *session_info
 227                 = ldb_get_opaque(ldb, "sessionInfo");
 228         const struct dom_sid *domain_sid = samdb_domain_sid(ldb);
 229         char *sddl_sd;
 230         struct dom_sid *default_owner;
 231         struct dom_sid *default_group;
 232
 233         if (object) {
 234                 user_descriptor = talloc(mem_ctx, struct security_descriptor);
 235                 if (!user_descriptor) {
 236                         return NULL;
 237                 }
 238                 ndr_err = ndr_pull_struct_blob(object, user_descriptor,
 239                                                user_descriptor,
 240                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 241
 242                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 243                         talloc_free(user_descriptor);
 244                         return NULL;
 245                 }
 246         } else {
 247                 user_descriptor = get_sd_unpacked(module, mem_ctx, objectclass);
 248         }
 249
 250         if (old_sd) {
 251                 old_descriptor = talloc(mem_ctx, struct security_descriptor);
 252                 if (!old_descriptor) {
 253                         return NULL;
 254                 }
 255                 ndr_err = ndr_pull_struct_blob(old_sd, old_descriptor,
 256                                                old_descriptor,
 257                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 258
 259                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 260                         talloc_free(old_descriptor);
 261                         return NULL;
 262                 }
 263         }
 264
 265         if (parent) {
 266                 parent_descriptor = talloc(mem_ctx, struct security_descriptor);
 267                 if (!parent_descriptor) {
 268                         return NULL;
 269                 }
 270                 ndr_err = ndr_pull_struct_blob(parent, parent_descriptor,
 271                                                parent_descriptor,
 272                                                (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 273
 274                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 275                         talloc_free(parent_descriptor);
 276                         return NULL;
 277                 }
 278         }
 279
 280         default_owner = get_default_ag(mem_ctx, dn,
 281                                        session_info->security_token, ldb);
 282         default_group = get_default_group(mem_ctx, ldb, default_owner);
 283         new_sd = create_security_descriptor(mem_ctx, parent_descriptor, user_descriptor, true,
 284                                             NULL, SEC_DACL_AUTO_INHERIT|SEC_SACL_AUTO_INHERIT,
 285                                             session_info->security_token,
 286                                             default_owner, default_group,
 287                                             map_generic_rights_ds);
 288         if (!new_sd) {
 289                 return NULL;
 290         }
 291         final_sd = descr_handle_sd_flags(mem_ctx, new_sd, old_descriptor, sd_flags);
 292
 293         if (!final_sd) {
 294                 return NULL;
 295         }
 296
 297         if (final_sd->dacl) {
 298                 final_sd->dacl->revision = SECURITY_ACL_REVISION_ADS;
 299         }
 300         if (final_sd->sacl) {
 301                 final_sd->sacl->revision = SECURITY_ACL_REVISION_ADS;
 302         }
 303
 304         sddl_sd = sddl_encode(mem_ctx, final_sd, domain_sid);
 305         DEBUG(10, ("Object %s created with desriptor %s\n\n", ldb_dn_get_linearized(dn), sddl_sd));
 306
 307         linear_sd = talloc(mem_ctx, DATA_BLOB);
 308         if (!linear_sd) {
 309                 return NULL;
 310         }
 311
 312         ndr_err = ndr_push_struct_blob(linear_sd, mem_ctx,
 313                                        final_sd,
 314                                        (ndr_push_flags_fn_t)ndr_push_security_descriptor);
 315         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 316                 return NULL;
 317         }
 318
 319         return linear_sd;
 320 }
 321
 322 static DATA_BLOB *descr_get_descriptor_to_show(struct ldb_module *module,
 323                                                TALLOC_CTX *mem_ctx,
 324                                                struct ldb_val *sd,
 325                                                uint32_t sd_flags)
 326 {
 327         struct security_descriptor *old_sd, *final_sd;
 328         DATA_BLOB *linear_sd;
 329         enum ndr_err_code ndr_err;
 330
 331         old_sd = talloc(mem_ctx, struct security_descriptor);
 332         if (!old_sd) {
 333                 return NULL;
 334         }
 335         ndr_err = ndr_pull_struct_blob(sd, old_sd,
 336                                        old_sd,
 337                                        (ndr_pull_flags_fn_t)ndr_pull_security_descriptor);
 338
 339         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 340                 talloc_free(old_sd);
 341                 return NULL;
 342         }
 343
 344         final_sd = descr_handle_sd_flags(mem_ctx, old_sd, NULL, sd_flags);
 345
 346         if (!final_sd) {
 347                 return NULL;
 348         }
 349
 350         linear_sd = talloc(mem_ctx, DATA_BLOB);
 351         if (!linear_sd) {
 352                 return NULL;
 353         }
 354
 355         ndr_err = ndr_push_struct_blob(linear_sd, mem_ctx,
 356                                        final_sd,
 357                                        (ndr_push_flags_fn_t)ndr_push_security_descriptor);
 358         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 359                 return NULL;
 360         }
 361
 362         return linear_sd;
 363 }
 364
 365 static struct descriptor_context *descriptor_init_context(struct ldb_module *module,
 366                                                           struct ldb_request *req)
 367 {
 368         struct ldb_context *ldb;
 369         struct descriptor_context *ac;
 370
 371         ldb = ldb_module_get_ctx(module);
 372
 373         ac = talloc_zero(req, struct descriptor_context);
 374         if (ac == NULL) {
 375                 ldb_set_errstring(ldb, "Out of Memory");
 376                 return NULL;
 377         }
 378
 379         ac->module = module;
 380         ac->req = req;
 381         return ac;
 382 }
 383
 384 static int descriptor_search_callback(struct ldb_request *req, struct ldb_reply *ares)
 385 {
 386         struct descriptor_context *ac;
 387         struct ldb_control *sd_control;
 388         struct ldb_val *sd_val = NULL;
 389         struct ldb_message_element *sd_el;
 390         DATA_BLOB *show_sd;
 391         int ret;
 392         uint32_t sd_flags = 0;
 393
 394         ac = talloc_get_type(req->context, struct descriptor_context);
 395
 396         if (!ares) {
 397                 ret = LDB_ERR_OPERATIONS_ERROR;
 398                 goto fail;
 399         }
 400         if (ares->error != LDB_SUCCESS) {
 401                 return ldb_module_done(ac->req, ares->controls,
 402                                         ares->response, ares->error);
 403         }
 404
 405         sd_control = ldb_request_get_control(ac->req, LDB_CONTROL_SD_FLAGS_OID);
 406         if (sd_control) {
 407                 struct ldb_sd_flags_control *sdctr = (struct ldb_sd_flags_control *)sd_control->data;
 408                 sd_flags = sdctr->secinfo_flags;
 409                 /* we only care for the last 4 bits */
 410                 sd_flags = sd_flags & 0x0000000F;
 411                 if (sd_flags == 0) {
 412                         /* MS-ADTS 3.1.1.3.4.1.11 says that no bits
 413                            equals all 4 bits */
 414                         sd_flags = 0xF;
 415                 }
 416         }
 417
 418         switch (ares->type) {
 419         case LDB_REPLY_ENTRY:
 420                 if (sd_flags != 0) {
 421                         sd_el = ldb_msg_find_element(ares->message, "nTSecurityDescriptor");
 422                         if (sd_el) {
 423                                 sd_val = sd_el->values;
 424                         }
 425                 }
 426                 if (sd_val) {
 427                         show_sd = descr_get_descriptor_to_show(ac->module, ac->req,
 428                                                                sd_val, sd_flags);
 429                         if (!show_sd) {
 430                                 ret = LDB_ERR_OPERATIONS_ERROR;
 431                                 goto fail;
 432                         }
 433                         ldb_msg_remove_attr(ares->message, "nTSecurityDescriptor");
 434                         ret = ldb_msg_add_steal_value(ares->message, "nTSecurityDescriptor", show_sd);
 435                         if (ret != LDB_SUCCESS) {
 436                                 goto fail;
 437                         }
 438                 }
 439                 return ldb_module_send_entry(ac->req, ares->message, ares->controls);
 440
 441         case LDB_REPLY_REFERRAL:
 442                 return ldb_module_send_referral(ac->req, ares->referral);
 443
 444         case LDB_REPLY_DONE:
 445                 return ldb_module_done(ac->req, ares->controls,
 446                                         ares->response, ares->error);
 447         }
 448
 449 fail:
 450         talloc_free(ares);
 451         return ldb_module_done(ac->req, NULL, NULL, ret);
 452 }
 453
 454 static int descriptor_add(struct ldb_module *module, struct ldb_request *req)
 455 {
 456         struct ldb_context *ldb;
 457         struct ldb_request *add_req;
 458         struct ldb_message *msg;
 459         struct ldb_result *parent_res;
 460         const struct ldb_val *parent_sd = NULL;
 461         const struct ldb_val *user_sd;
 462         struct ldb_dn *parent_dn, *dn, *nc_root;
 463         struct ldb_message_element *objectclass_element, *sd_element;
 464         int ret;
 465         const struct dsdb_schema *schema;
 466         DATA_BLOB *sd;
 467         const struct dsdb_class *objectclass;
 468         static const char * const parent_attrs[] = { "nTSecurityDescriptor", NULL };
 469         uint32_t instanceType;
 470         bool isNC = false;
 471
 472         ldb = ldb_module_get_ctx(module);
 473         dn = req->op.add.message->dn;
 474         user_sd = ldb_msg_find_ldb_val(req->op.add.message, "nTSecurityDescriptor");
 475         sd_element = ldb_msg_find_element(req->op.add.message, "nTSecurityDescriptor");
 476         /* nTSecurityDescriptor without a value is an error, letting through so it is handled */
 477         if (user_sd == NULL && sd_element) {
 478                 return ldb_next_request(module, req);
 479         }
 480
 481         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: %s\n", ldb_dn_get_linearized(dn));
 482
 483         /* do not manipulate our control entries */
 484         if (ldb_dn_is_special(dn)) {
 485                 return ldb_next_request(module, req);
 486         }
 487
 488         instanceType = ldb_msg_find_attr_as_uint(req->op.add.message, "instanceType", 0);
 489
 490         if (instanceType & INSTANCE_TYPE_IS_NC_HEAD) {
 491                 isNC = true;
 492         }
 493
 494         if (!isNC) {
 495                 ret = dsdb_find_nc_root(ldb, req, dn, &nc_root);
 496                 if (ret != LDB_SUCCESS) {
 497                         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: Could not find NC root for %s\n",
 498                                 ldb_dn_get_linearized(dn));
 499                         return ret;
 500                 }
 501
 502                 if (ldb_dn_compare(dn, nc_root) == 0) {
 503                         DEBUG(0, ("Found DN %s being a NC by the old method\n", ldb_dn_get_linearized(dn)));
 504                         isNC = true;
 505                 }
 506         }
 507
 508         if (isNC) {
 509                 DEBUG(2, ("DN: %s is a NC\n", ldb_dn_get_linearized(dn)));
 510         }
 511         if (!isNC) {
 512                 /* if the object has a parent, retrieve its SD to
 513                  * use for calculation. Unfortunately we do not yet have
 514                  * instanceType, so we use dsdb_find_nc_root. */
 515
 516                 parent_dn = ldb_dn_get_parent(req, dn);
 517                 if (parent_dn == NULL) {
 518                         return ldb_oom(ldb);
 519                 }
 520
 521                 /* we aren't any NC */
 522                 ret = dsdb_module_search_dn(module, req, &parent_res, parent_dn,
 523                                             parent_attrs,
 524                                             DSDB_FLAG_NEXT_MODULE |
 525                                             DSDB_FLAG_AS_SYSTEM |
 526                                             DSDB_SEARCH_SHOW_RECYCLED,
 527                                             req);
 528                 if (ret != LDB_SUCCESS) {
 529                         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_add: Could not find SD for %s\n",
 530                                   ldb_dn_get_linearized(parent_dn));
 531                         return ret;
 532                 }
 533                 if (parent_res->count != 1) {
 534                         return ldb_operr(ldb);
 535                 }
 536                 parent_sd = ldb_msg_find_ldb_val(parent_res->msgs[0], "nTSecurityDescriptor");
 537         }
 538
 539         schema = dsdb_get_schema(ldb, req);
 540
 541         objectclass_element = ldb_msg_find_element(req->op.add.message, "objectClass");
 542         if (objectclass_element == NULL) {
 543                 return ldb_operr(ldb);
 544         }
 545
 546         objectclass = dsdb_get_last_structural_class(schema,
 547                                                      objectclass_element);
 548         if (objectclass == NULL) {
 549                 return ldb_operr(ldb);
 550         }
 551
 552         sd = get_new_descriptor(module, dn, req,
 553                                 objectclass, parent_sd,
 554                                 user_sd, NULL, 0);
 555         msg = ldb_msg_copy_shallow(req, req->op.add.message);
 556         if (sd != NULL) {
 557                 if (sd_element != NULL) {
 558                         sd_element->values[0] = *sd;
 559                 } else {
 560                         ret = ldb_msg_add_steal_value(msg,
 561                                                       "nTSecurityDescriptor",
 562                                                       sd);
 563                         if (ret != LDB_SUCCESS) {
 564                                 return ret;
 565                         }
 566                 }
 567         }
 568
 569         ret = ldb_build_add_req(&add_req, ldb, req,
 570                                 msg,
 571                                 req->controls,
 572                                 req, dsdb_next_callback,
 573                                 req);
 574         LDB_REQ_SET_LOCATION(add_req);
 575         if (ret != LDB_SUCCESS) {
 576                 return ldb_error(ldb, ret,
 577                                  "descriptor_add: Error creating new add request.");
 578         }
 579
 580         return ldb_next_request(module, add_req);
 581 }
 582
 583 static int descriptor_modify(struct ldb_module *module, struct ldb_request *req)
 584 {
 585         struct ldb_context *ldb;
 586         struct ldb_control *sd_recalculate_control, *sd_flags_control;
 587         struct ldb_request *mod_req;
 588         struct ldb_message *msg;
 589         struct ldb_result *current_res, *parent_res;
 590         const struct ldb_val *old_sd = NULL;
 591         const struct ldb_val *parent_sd = NULL;
 592         const struct ldb_val *user_sd;
 593         struct ldb_dn *parent_dn, *dn;
 594         struct ldb_message_element *objectclass_element;
 595         int ret;
 596         uint32_t instanceType, sd_flags = 0;
 597         const struct dsdb_schema *schema;
 598         DATA_BLOB *sd;
 599         const struct dsdb_class *objectclass;
 600         static const char * const parent_attrs[] = { "nTSecurityDescriptor", NULL };
 601         static const char * const current_attrs[] = { "nTSecurityDescriptor",
 602                                                       "instanceType",
 603                                                       "objectClass", NULL };
 604         ldb = ldb_module_get_ctx(module);
 605         dn = req->op.mod.message->dn;
 606         user_sd = ldb_msg_find_ldb_val(req->op.mod.message, "nTSecurityDescriptor");
 607         /* This control forces the recalculation of the SD also when
 608          * no modification is performed. */
 609         sd_recalculate_control = ldb_request_get_control(req,
 610                                              LDB_CONTROL_RECALCULATE_SD_OID);
 611         if (!user_sd && !sd_recalculate_control) {
 612                 return ldb_next_request(module, req);
 613         }
 614
 615         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_modify: %s\n", ldb_dn_get_linearized(dn));
 616
 617         /* do not manipulate our control entries */
 618         if (ldb_dn_is_special(dn)) {
 619                 return ldb_next_request(module, req);
 620         }
 621
 622         ret = dsdb_module_search_dn(module, req, &current_res, dn,
 623                                     current_attrs,
 624                                     DSDB_FLAG_NEXT_MODULE |
 625                                     DSDB_FLAG_AS_SYSTEM |
 626                                     DSDB_SEARCH_SHOW_RECYCLED,
 627                                     req);
 628         if (ret != LDB_SUCCESS) {
 629                 ldb_debug(ldb, LDB_DEBUG_ERROR,"descriptor_modify: Could not find %s\n",
 630                           ldb_dn_get_linearized(dn));
 631                 return ret;
 632         }
 633
 634         instanceType = ldb_msg_find_attr_as_uint(current_res->msgs[0],
 635                                                  "instanceType", 0);
 636         /* if the object has a parent, retrieve its SD to
 637          * use for calculation */
 638         if (!ldb_dn_is_null(current_res->msgs[0]->dn) &&
 639             !(instanceType & INSTANCE_TYPE_IS_NC_HEAD)) {
 640                 parent_dn = ldb_dn_get_parent(req, dn);
 641                 if (parent_dn == NULL) {
 642                         return ldb_oom(ldb);
 643                 }
 644                 ret = dsdb_module_search_dn(module, req, &parent_res, parent_dn,
 645                                             parent_attrs,
 646                                             DSDB_FLAG_NEXT_MODULE |
 647                                             DSDB_FLAG_AS_SYSTEM |
 648                                             DSDB_SEARCH_SHOW_RECYCLED,
 649                                             req);
 650                 if (ret != LDB_SUCCESS) {
 651                         ldb_debug(ldb, LDB_DEBUG_ERROR, "descriptor_modify: Could not find SD for %s\n",
 652                                   ldb_dn_get_linearized(parent_dn));
 653                         return ret;
 654                 }
 655                 if (parent_res->count != 1) {
 656                         return ldb_operr(ldb);
 657                 }
 658                 parent_sd = ldb_msg_find_ldb_val(parent_res->msgs[0], "nTSecurityDescriptor");
 659         }
 660         sd_flags_control = ldb_request_get_control(req, LDB_CONTROL_SD_FLAGS_OID);
 661
 662         schema = dsdb_get_schema(ldb, req);
 663
 664         objectclass_element = ldb_msg_find_element(current_res->msgs[0], "objectClass");
 665         if (objectclass_element == NULL) {
 666                 return ldb_operr(ldb);
 667         }
 668
 669         objectclass = dsdb_get_last_structural_class(schema,
 670                                                      objectclass_element);
 671         if (objectclass == NULL) {
 672                 return ldb_operr(ldb);
 673         }
 674
 675         if (sd_flags_control) {
 676                 struct ldb_sd_flags_control *sdctr = (struct ldb_sd_flags_control *)sd_flags_control->data;
 677                 sd_flags = sdctr->secinfo_flags;
 678                 /* we only care for the last 4 bits */
 679                 sd_flags = sd_flags & 0x0000000F;
 680         }
 681         if (sd_flags != 0) {
 682                 old_sd = ldb_msg_find_ldb_val(current_res->msgs[0], "nTSecurityDescriptor");
 683         }
 684
 685         sd = get_new_descriptor(module, dn, req,
 686                                 objectclass, parent_sd,
 687                                 user_sd, old_sd, sd_flags);
 688         msg = ldb_msg_copy_shallow(req, req->op.mod.message);
 689         if (sd != NULL) {
 690                 struct ldb_message_element *sd_element;
 691                 if (user_sd != NULL) {
 692                         sd_element = ldb_msg_find_element(msg,
 693                                                           "nTSecurityDescriptor");
 694                         sd_element->values[0] = *sd;
 695                 } else if (sd_recalculate_control != NULL) {
 696                         /* In this branch we really do force the recalculation
 697                          * of the SD */
 698                         ldb_msg_remove_attr(msg, "nTSecurityDescriptor");
 699
 700                         ret = ldb_msg_add_steal_value(msg,
 701                                                       "nTSecurityDescriptor",
 702                                                       sd);
 703                         if (ret != LDB_SUCCESS) {
 704                                 return ldb_error(ldb, ret,
 705                                          "descriptor_modify: Could not replace SD value in message.");
 706                         }
 707                         sd_element = ldb_msg_find_element(msg,
 708                                                           "nTSecurityDescriptor");
 709                         sd_element->flags = LDB_FLAG_MOD_REPLACE;
 710                 }
 711         }
 712
 713         /* mark the controls as non-critical since we've handled them */
 714         if (sd_flags_control != NULL) {
 715                 sd_flags_control->critical = 0;
 716         }
 717         if (sd_recalculate_control != NULL) {
 718                 sd_recalculate_control->critical = 0;
 719         }
 720
 721         ret = ldb_build_mod_req(&mod_req, ldb, req,
 722                                 msg,
 723                                 req->controls,
 724                                 req,
 725                                 dsdb_next_callback,
 726                                 req);
 727         LDB_REQ_SET_LOCATION(mod_req);
 728         if (ret != LDB_SUCCESS) {
 729                 return ret;
 730         }
 731
 732         return ldb_next_request(module, mod_req);
 733 }
 734
 735 static int descriptor_search(struct ldb_module *module, struct ldb_request *req)
 736 {
 737         int ret;
 738         struct ldb_context *ldb;
 739         struct ldb_control *sd_control;
 740         struct ldb_request *down_req;
 741         struct descriptor_context *ac;
 742
 743         sd_control = ldb_request_get_control(req, LDB_CONTROL_SD_FLAGS_OID);
 744         if (!sd_control) {
 745                 return ldb_next_request(module, req);
 746         }
 747
 748         ldb = ldb_module_get_ctx(module);
 749         ac = descriptor_init_context(module, req);
 750         if (ac == NULL) {
 751                 return ldb_operr(ldb);
 752         }
 753
 754         ret = ldb_build_search_req_ex(&down_req, ldb, ac,
 755                                       req->op.search.base,
 756                                       req->op.search.scope,
 757                                       req->op.search.tree,
 758                                       req->op.search.attrs,
 759                                       req->controls,
 760                                       ac, descriptor_search_callback,
 761                                       ac->req);
 762         LDB_REQ_SET_LOCATION(down_req);
 763         if (ret != LDB_SUCCESS) {
 764                 return ret;
 765         }
 766         /* mark it as handled */
 767         if (sd_control) {
 768                 sd_control->critical = 0;
 769         }
 770
 771         return ldb_next_request(ac->module, down_req);
 772 }
 773 /* TODO */
 774 static int descriptor_rename(struct ldb_module *module, struct ldb_request *req)
 775 {
 776         struct ldb_context *ldb = ldb_module_get_ctx(module);
 777         ldb_debug(ldb, LDB_DEBUG_TRACE,"descriptor_rename: %s\n", ldb_dn_get_linearized(req->op.rename.olddn));
 778
 779         /* do not manipulate our control entries */
 780         if (ldb_dn_is_special(req->op.rename.olddn)) {
 781                 return ldb_next_request(module, req);
 782         }
 783
 784         return ldb_next_request(module, req);
 785 }
 786
 787 static int descriptor_init(struct ldb_module *module)
 788 {
 789         int ret = ldb_mod_register_control(module, LDB_CONTROL_SD_FLAGS_OID);
 790         struct ldb_context *ldb = ldb_module_get_ctx(module);
 791         if (ret != LDB_SUCCESS) {
 792                 ldb_debug(ldb, LDB_DEBUG_ERROR,
 793                         "descriptor: Unable to register control with rootdse!\n");
 794                 return ldb_operr(ldb);
 795         }
 796         return ldb_next_init(module);
 797 }
 798
 799
 800 static const struct ldb_module_ops ldb_descriptor_module_ops = {
 801         .name          = "descriptor",
 802         .search        = descriptor_search,
 803         .add           = descriptor_add,
 804         .modify        = descriptor_modify,
 805         .rename        = descriptor_rename,
 806         .init_context  = descriptor_init
 807 };
 808
 809 int ldb_descriptor_module_init(const char *version)
 810 {
 811         LDB_MODULE_CHECK_VERSION(version);
 812         return ldb_register_module(&ldb_descriptor_module_ops);
 813 }