source4/dsdb/samdb/ldb_modules/extended_dn_in.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Simo Sorce 2005-2008
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2007-2008
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 /*
  22  *  Name: ldb
  23  *
  24  *  Component: ldb extended dn control module
  25  *
  26  *  Description: this module interprets DNs of the form <SID=S-1-2-4456> into normal DNs.
  27  *
  28  *  Authors: Simo Sorce
  29  *           Andrew Bartlett
  30  */
  31
  32 #include "includes.h"
  33 #include "ldb/include/ldb.h"
  34 #include "ldb/include/ldb_errors.h"
  35 #include "ldb/include/ldb_module.h"
  36
  37 /*
  38   TODO: if relax is not set then we need to reject the fancy RMD_* and
  39   DELETED extended DN codes
  40  */
  41
  42 /* search */
  43 struct extended_search_context {
  44         struct ldb_module *module;
  45         struct ldb_request *req;
  46         struct ldb_dn *basedn;
  47         char *wellknown_object;
  48         int extended_type;
  49 };
  50
  51 /* An extra layer of indirection because LDB does not allow the original request to be altered */
  52
  53 static int extended_final_callback(struct ldb_request *req, struct ldb_reply *ares)
  54 {
  55         int ret = LDB_ERR_OPERATIONS_ERROR;
  56         struct extended_search_context *ac;
  57         ac = talloc_get_type(req->context, struct extended_search_context);
  58
  59         if (ares->error != LDB_SUCCESS) {
  60                 ret = ldb_module_done(ac->req, ares->controls,
  61                                       ares->response, ares->error);
  62         } else {
  63                 switch (ares->type) {
  64                 case LDB_REPLY_ENTRY:
  65
  66                         ret = ldb_module_send_entry(ac->req, ares->message, ares->controls);
  67                         break;
  68                 case LDB_REPLY_REFERRAL:
  69
  70                         ret = ldb_module_send_referral(ac->req, ares->referral);
  71                         break;
  72                 case LDB_REPLY_DONE:
  73
  74                         ret = ldb_module_done(ac->req, ares->controls,
  75                                               ares->response, ares->error);
  76                         break;
  77                 }
  78         }
  79         return ret;
  80 }
  81
  82 static int extended_base_callback(struct ldb_request *req, struct ldb_reply *ares)
  83 {
  84         struct extended_search_context *ac;
  85         struct ldb_request *down_req;
  86         struct ldb_message_element *el;
  87         int ret;
  88         unsigned int i;
  89         size_t wkn_len = 0;
  90         char *valstr = NULL;
  91         const char *found = NULL;
  92
  93         ac = talloc_get_type(req->context, struct extended_search_context);
  94
  95         if (!ares) {
  96                 return ldb_module_done(ac->req, NULL, NULL,
  97                                         LDB_ERR_OPERATIONS_ERROR);
  98         }
  99         if (ares->error != LDB_SUCCESS) {
 100                 return ldb_module_done(ac->req, ares->controls,
 101                                         ares->response, ares->error);
 102         }
 103
 104         switch (ares->type) {
 105         case LDB_REPLY_ENTRY:
 106                 if (!ac->wellknown_object) {
 107                         ac->basedn = talloc_steal(ac, ares->message->dn);
 108                         break;
 109                 }
 110
 111                 wkn_len = strlen(ac->wellknown_object);
 112
 113                 el = ldb_msg_find_element(ares->message, "wellKnownObjects");
 114                 if (!el) {
 115                         ac->basedn = NULL;
 116                         break;
 117                 }
 118
 119                 for (i=0; i < el->num_values; i++) {
 120                         valstr = talloc_strndup(ac,
 121                                                 (const char *)el->values[i].data,
 122                                                 el->values[i].length);
 123                         if (!valstr) {
 124                                 ldb_oom(ldb_module_get_ctx(ac->module));
 125                                 return ldb_module_done(ac->req, NULL, NULL,
 126                                                        LDB_ERR_OPERATIONS_ERROR);
 127                         }
 128
 129                         if (strncasecmp(valstr, ac->wellknown_object, wkn_len) != 0) {
 130                                 talloc_free(valstr);
 131                                 continue;
 132                         }
 133
 134                         found = &valstr[wkn_len];
 135                         break;
 136                 }
 137
 138                 if (!found) {
 139                         break;
 140                 }
 141
 142                 ac->basedn = ldb_dn_new(ac, ldb_module_get_ctx(ac->module), found);
 143                 talloc_free(valstr);
 144                 if (!ac->basedn) {
 145                         ldb_oom(ldb_module_get_ctx(ac->module));
 146                         return ldb_module_done(ac->req, NULL, NULL,
 147                                                LDB_ERR_OPERATIONS_ERROR);
 148                 }
 149
 150                 break;
 151
 152         case LDB_REPLY_REFERRAL:
 153                 break;
 154
 155         case LDB_REPLY_DONE:
 156
 157                 if (!ac->basedn) {
 158                         const char *str = talloc_asprintf(req, "Base-DN '%s' not found",
 159                                                           ldb_dn_get_extended_linearized(req, ac->req->op.search.base, 1));
 160                         ldb_set_errstring(ldb_module_get_ctx(ac->module), str);
 161                         return ldb_module_done(ac->req, NULL, NULL,
 162                                                LDB_ERR_NO_SUCH_OBJECT);
 163                 }
 164
 165                 switch (ac->req->operation) {
 166                 case LDB_SEARCH:
 167                         ret = ldb_build_search_req_ex(&down_req,
 168                                                       ldb_module_get_ctx(ac->module), ac->req,
 169                                                       ac->basedn,
 170                                                       ac->req->op.search.scope,
 171                                                       ac->req->op.search.tree,
 172                                                       ac->req->op.search.attrs,
 173                                                       ac->req->controls,
 174                                                       ac, extended_final_callback,
 175                                                       ac->req);
 176                         ldb_req_mark_trusted(down_req);
 177                         LDB_REQ_SET_LOCATION(down_req);
 178                         break;
 179                 case LDB_ADD:
 180                 {
 181                         struct ldb_message *add_msg = ldb_msg_copy_shallow(ac, ac->req->op.add.message);
 182                         if (!add_msg) {
 183                                 ldb_oom(ldb_module_get_ctx(ac->module));
 184                                 return ldb_module_done(ac->req, NULL, NULL,
 185                                                        LDB_ERR_OPERATIONS_ERROR);
 186                         }
 187
 188                         add_msg->dn = ac->basedn;
 189
 190                         ret = ldb_build_add_req(&down_req,
 191                                                 ldb_module_get_ctx(ac->module), ac->req,
 192                                                 add_msg,
 193                                                 ac->req->controls,
 194                                                 ac, extended_final_callback,
 195                                                 ac->req);
 196                         LDB_REQ_SET_LOCATION(down_req);
 197                         break;
 198                 }
 199                 case LDB_MODIFY:
 200                 {
 201                         struct ldb_message *mod_msg = ldb_msg_copy_shallow(ac, ac->req->op.mod.message);
 202                         if (!mod_msg) {
 203                                 ldb_oom(ldb_module_get_ctx(ac->module));
 204                                 return ldb_module_done(ac->req, NULL, NULL,
 205                                                        LDB_ERR_OPERATIONS_ERROR);
 206                         }
 207
 208                         mod_msg->dn = ac->basedn;
 209
 210                         ret = ldb_build_mod_req(&down_req,
 211                                                 ldb_module_get_ctx(ac->module), ac->req,
 212                                                 mod_msg,
 213                                                 ac->req->controls,
 214                                                 ac, extended_final_callback,
 215                                                 ac->req);
 216                         LDB_REQ_SET_LOCATION(down_req);
 217                         break;
 218                 }
 219                 case LDB_DELETE:
 220                         ret = ldb_build_del_req(&down_req,
 221                                                 ldb_module_get_ctx(ac->module), ac->req,
 222                                                 ac->basedn,
 223                                                 ac->req->controls,
 224                                                 ac, extended_final_callback,
 225                                                 ac->req);
 226                         LDB_REQ_SET_LOCATION(down_req);
 227                         break;
 228                 case LDB_RENAME:
 229                         ret = ldb_build_rename_req(&down_req,
 230                                                    ldb_module_get_ctx(ac->module), ac->req,
 231                                                    ac->basedn,
 232                                                    ac->req->op.rename.newdn,
 233                                                    ac->req->controls,
 234                                                    ac, extended_final_callback,
 235                                                    ac->req);
 236                         LDB_REQ_SET_LOCATION(down_req);
 237                         break;
 238                 default:
 239                         return ldb_module_done(ac->req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR);
 240                 }
 241
 242                 if (ret != LDB_SUCCESS) {
 243                         return ldb_module_done(ac->req, NULL, NULL, ret);
 244                 }
 245
 246                 return ldb_next_request(ac->module, down_req);
 247         }
 248         talloc_free(ares);
 249         return LDB_SUCCESS;
 250 }
 251
 252 static int extended_dn_in_fix(struct ldb_module *module, struct ldb_request *req, struct ldb_dn *dn)
 253 {
 254         struct extended_search_context *ac;
 255         struct ldb_request *down_req;
 256         int ret;
 257         struct ldb_dn *base_dn = NULL;
 258         enum ldb_scope base_dn_scope = LDB_SCOPE_BASE;
 259         const char *base_dn_filter = NULL;
 260         const char * const *base_dn_attrs = NULL;
 261         char *wellknown_object = NULL;
 262         static const char *no_attr[] = {
 263                 NULL
 264         };
 265         static const char *wkattr[] = {
 266                 "wellKnownObjects",
 267                 NULL
 268         };
 269         bool all_partitions = false;
 270
 271         if (!ldb_dn_has_extended(dn)) {
 272                 /* Move along there isn't anything to see here */
 273                 return ldb_next_request(module, req);
 274         } else {
 275                 /* It looks like we need to map the DN */
 276                 const struct ldb_val *sid_val, *guid_val, *wkguid_val;
 277                 int num_components = ldb_dn_get_comp_num(dn);
 278                 int num_ex_components = ldb_dn_get_extended_comp_num(dn);
 279
 280                 /*
 281                   windows ldap searchs don't allow a baseDN with more
 282                   than one extended component, or an extended
 283                   component and a string DN
 284
 285                   We only enforce this over ldap, not for internal
 286                   use, as there are just too many places where we
 287                   internally want to use a DN that has come from a
 288                   search with extended DN enabled, or comes from a DRS
 289                   naming context.
 290
 291                   Enforcing this would also make debugging samba much
 292                   harder, as we'd need to use ldb_dn_minimise() in a
 293                   lot of places, and that would lose the DN string
 294                   which is so useful for working out what a request is
 295                   for
 296                  */
 297                 if ((num_components != 0 || num_ex_components != 1) &&
 298                     ldb_req_is_untrusted(req)) {
 299                         return ldb_error(ldb_module_get_ctx(module),
 300                                          LDB_ERR_INVALID_DN_SYNTAX, "invalid number of DN components");
 301                 }
 302
 303                 sid_val = ldb_dn_get_extended_component(dn, "SID");
 304                 guid_val = ldb_dn_get_extended_component(dn, "GUID");
 305                 wkguid_val = ldb_dn_get_extended_component(dn, "WKGUID");
 306
 307                 if (sid_val) {
 308                         all_partitions = true;
 309                         base_dn = ldb_get_default_basedn(ldb_module_get_ctx(module));
 310                         base_dn_filter = talloc_asprintf(req, "(objectSid=%s)",
 311                                                          ldb_binary_encode(req, *sid_val));
 312                         if (!base_dn_filter) {
 313                                 return ldb_oom(ldb_module_get_ctx(module));
 314                         }
 315                         base_dn_scope = LDB_SCOPE_SUBTREE;
 316                         base_dn_attrs = no_attr;
 317
 318                 } else if (guid_val) {
 319
 320                         all_partitions = true;
 321                         base_dn = ldb_get_default_basedn(ldb_module_get_ctx(module));
 322                         base_dn_filter = talloc_asprintf(req, "(objectGUID=%s)",
 323                                                          ldb_binary_encode(req, *guid_val));
 324                         if (!base_dn_filter) {
 325                                 return ldb_oom(ldb_module_get_ctx(module));
 326                         }
 327                         base_dn_scope = LDB_SCOPE_SUBTREE;
 328                         base_dn_attrs = no_attr;
 329
 330
 331                 } else if (wkguid_val) {
 332                         char *wkguid_dup;
 333                         char *tail_str;
 334                         char *p;
 335
 336                         wkguid_dup = talloc_strndup(req, (char *)wkguid_val->data, wkguid_val->length);
 337
 338                         p = strchr(wkguid_dup, ',');
 339                         if (!p) {
 340                                 return ldb_error(ldb_module_get_ctx(module), LDB_ERR_INVALID_DN_SYNTAX,
 341                                                  "Invalid WKGUID format");
 342                         }
 343
 344                         p[0] = '\0';
 345                         p++;
 346
 347                         wellknown_object = talloc_asprintf(req, "B:32:%s:", wkguid_dup);
 348                         if (!wellknown_object) {
 349                                 return ldb_oom(ldb_module_get_ctx(module));
 350                         }
 351
 352                         tail_str = p;
 353
 354                         base_dn = ldb_dn_new(req, ldb_module_get_ctx(module), tail_str);
 355                         talloc_free(wkguid_dup);
 356                         if (!base_dn) {
 357                                 return ldb_oom(ldb_module_get_ctx(module));
 358                         }
 359                         base_dn_filter = talloc_strdup(req, "(objectClass=*)");
 360                         if (!base_dn_filter) {
 361                                 return ldb_oom(ldb_module_get_ctx(module));
 362                         }
 363                         base_dn_scope = LDB_SCOPE_BASE;
 364                         base_dn_attrs = wkattr;
 365                 } else {
 366                         return ldb_error(ldb_module_get_ctx(module), LDB_ERR_INVALID_DN_SYNTAX,
 367                                          "Invalid extended DN component");
 368                 }
 369
 370                 ac = talloc_zero(req, struct extended_search_context);
 371                 if (ac == NULL) {
 372                         return ldb_oom(ldb_module_get_ctx(module));
 373                 }
 374
 375                 ac->module = module;
 376                 ac->req = req;
 377                 ac->basedn = NULL;  /* Filled in if the search finds the DN by SID/GUID etc */
 378                 ac->wellknown_object = wellknown_object;
 379
 380                 /* If the base DN was an extended DN (perhaps a well known
 381                  * GUID) then search for that, so we can proceed with the original operation */
 382
 383                 ret = ldb_build_search_req(&down_req,
 384                                            ldb_module_get_ctx(module), ac,
 385                                            base_dn,
 386                                            base_dn_scope,
 387                                            base_dn_filter,
 388                                            base_dn_attrs,
 389                                            req->controls,
 390                                            ac, extended_base_callback,
 391                                            req);
 392                 LDB_REQ_SET_LOCATION(down_req);
 393                 if (ret != LDB_SUCCESS) {
 394                         return ldb_operr(ldb_module_get_ctx(module));
 395                 }
 396
 397                 if (all_partitions) {
 398                         struct ldb_search_options_control *control;
 399                         control = talloc(down_req, struct ldb_search_options_control);
 400                         control->search_options = 2;
 401                         ret = ldb_request_replace_control(down_req,
 402                                                       LDB_CONTROL_SEARCH_OPTIONS_OID,
 403                                                       true, control);
 404                         if (ret != LDB_SUCCESS) {
 405                                 ldb_oom(ldb_module_get_ctx(module));
 406                                 return ret;
 407                         }
 408                 }
 409
 410                 /* perform the search */
 411                 return ldb_next_request(module, down_req);
 412         }
 413 }
 414
 415 static int extended_dn_in_search(struct ldb_module *module, struct ldb_request *req)
 416 {
 417         return extended_dn_in_fix(module, req, req->op.search.base);
 418 }
 419
 420 static int extended_dn_in_modify(struct ldb_module *module, struct ldb_request *req)
 421 {
 422         return extended_dn_in_fix(module, req, req->op.mod.message->dn);
 423 }
 424
 425 static int extended_dn_in_del(struct ldb_module *module, struct ldb_request *req)
 426 {
 427         return extended_dn_in_fix(module, req, req->op.del.dn);
 428 }
 429
 430 static int extended_dn_in_rename(struct ldb_module *module, struct ldb_request *req)
 431 {
 432         return extended_dn_in_fix(module, req, req->op.rename.olddn);
 433 }
 434
 435 static const struct ldb_module_ops ldb_extended_dn_in_module_ops = {
 436         .name              = "extended_dn_in",
 437         .search            = extended_dn_in_search,
 438         .modify            = extended_dn_in_modify,
 439         .del               = extended_dn_in_del,
 440         .rename            = extended_dn_in_rename,
 441 };
 442
 443 int ldb_extended_dn_in_module_init(const char *version)
 444 {
 445         LDB_MODULE_CHECK_VERSION(version);
 446         return ldb_register_module(&ldb_extended_dn_in_module_ops);
 447 }