/* ldb database library Copyright (C) Simo Sorce 2006-2008 Copyright (C) Andrew Bartlett 2005-2009 Copyright (C) Stefan Metzmacher 2009 Copyright (C) Matthias Dieter Wallnöfer 2010 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, see . */ /* * Name: ldb * * Component: objectclass attribute checking module * * Description: this checks the attributes on a directory entry (if they're * allowed, if the syntax is correct, if mandatory ones are missing, * denies the deletion of mandatory ones...). The module contains portions * of the "objectclass" and the "validate_update" LDB module. * * Author: Matthias Dieter Wallnöfer */ #include "includes.h" #include "ldb_module.h" #include "dsdb/samdb/samdb.h" struct oc_context { struct ldb_module *module; struct ldb_request *req; const struct dsdb_schema *schema; struct ldb_reply *search_res; struct ldb_reply *mod_ares; }; static struct oc_context *oc_init_context(struct ldb_module *module, struct ldb_request *req) { struct ldb_context *ldb; struct oc_context *ac; ldb = ldb_module_get_ctx(module); ac = talloc_zero(req, struct oc_context); if (ac == NULL) { ldb_oom(ldb); return NULL; } ac->module = module; ac->req = req; ac->schema = dsdb_get_schema(ldb, ac); return ac; } static int oc_op_callback(struct ldb_request *req, struct ldb_reply *ares); /* checks correctness of dSHeuristics attribute * as described in MS-ADTS 7.1.1.2.4.1.2 dSHeuristics */ static int oc_validate_dsheuristics(struct ldb_message_element *el) { if (el->num_values > 0) { if (el->values[0].length > DS_HR_LDAP_BYPASS_UPPER_LIMIT_BOUNDS) { return LDB_ERR_CONSTRAINT_VIOLATION; } else if (el->values[0].length >= DS_HR_TENTH_CHAR && el->values[0].data[DS_HR_TENTH_CHAR-1] != '1') { return LDB_ERR_CONSTRAINT_VIOLATION; } } return LDB_SUCCESS; } static int attr_handler(struct oc_context *ac) { struct ldb_context *ldb; struct ldb_message *msg; struct ldb_request *child_req; const struct dsdb_attribute *attr; unsigned int i; int ret; WERROR werr; struct dsdb_syntax_ctx syntax_ctx; ldb = ldb_module_get_ctx(ac->module); if (ac->req->operation == LDB_ADD) { msg = ldb_msg_copy_shallow(ac, ac->req->op.add.message); } else { msg = ldb_msg_copy_shallow(ac, ac->req->op.mod.message); } if (msg == NULL) { return ldb_oom(ldb); } /* initialize syntax checking context */ dsdb_syntax_ctx_init(&syntax_ctx, ldb, ac->schema); /* Check if attributes exist in the schema, if the values match, * if they're not operational and fix the names to the match the schema * case */ for (i = 0; i < msg->num_elements; i++) { attr = dsdb_attribute_by_lDAPDisplayName(ac->schema, msg->elements[i].name); if (attr == NULL) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' was not found in the schema!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_NO_SUCH_ATTRIBUTE; } if ((attr->linkID & 1) == 1) { /* Odd is for the target. Illegal to modify */ ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' must not be modified directly, it is a linked attribute", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_UNWILLING_TO_PERFORM; } if (!(msg->elements[i].flags & LDB_FLAG_INTERNAL_DISABLE_VALIDATION)) { werr = attr->syntax->validate_ldb(&syntax_ctx, attr, &msg->elements[i]); if (!W_ERROR_IS_OK(werr)) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' contains at least one invalid value!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_INVALID_ATTRIBUTE_SYNTAX; } } if ((attr->systemFlags & DS_FLAG_ATTR_IS_CONSTRUCTED) != 0) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' is constructed!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); if (ac->req->operation == LDB_ADD) { return LDB_ERR_UNDEFINED_ATTRIBUTE_TYPE; } else { return LDB_ERR_CONSTRAINT_VIOLATION; } } /* "description" on AD is very special: it's nearly single- * valued (only on add operations it isn't). */ if ((ac->req->operation == LDB_MODIFY) && (ldb_attr_cmp(attr->lDAPDisplayName, "description") == 0)) { /* Multi-valued add or replace operations are always * denied */ if ((LDB_FLAG_MOD_TYPE(msg->elements[i].flags) != LDB_FLAG_MOD_DELETE) && (msg->elements[i].num_values > 1)) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' is changed using a multi-valued add or replace operation!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_ATTRIBUTE_OR_VALUE_EXISTS; } /* Add operations are only allowed if no value exists */ if (LDB_FLAG_MOD_TYPE(msg->elements[i].flags) == LDB_FLAG_MOD_ADD) { const char *attrs[] = { attr->lDAPDisplayName, NULL }; struct ldb_result *res; struct ldb_message_element *el; ret = ldb_search(ldb, ac, &res, msg->dn, LDB_SCOPE_BASE, attrs, NULL); if (ret != LDB_SUCCESS) { return ret; } el = ldb_msg_find_element(res->msgs[0], attr->lDAPDisplayName); if (el != NULL) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' is changed using an add operation, but there a value already exists!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_ATTRIBUTE_OR_VALUE_EXISTS; } talloc_free(res); } } /* "dSHeuristics" syntax check */ if (ldb_attr_cmp(attr->lDAPDisplayName, "dSHeuristics") == 0) { ret = oc_validate_dsheuristics(&(msg->elements[i])); if (ret != LDB_SUCCESS) { return ret; } } /* Substitute the attribute name to match in case */ msg->elements[i].name = attr->lDAPDisplayName; } if (ac->req->operation == LDB_ADD) { ret = ldb_build_add_req(&child_req, ldb, ac, msg, ac->req->controls, ac, oc_op_callback, ac->req); LDB_REQ_SET_LOCATION(child_req); } else { ret = ldb_build_mod_req(&child_req, ldb, ac, msg, ac->req->controls, ac, oc_op_callback, ac->req); LDB_REQ_SET_LOCATION(child_req); } if (ret != LDB_SUCCESS) { return ret; } return ldb_next_request(ac->module, child_req); } /* these are attributes which are left over from old ways of doing things in ldb, and are harmless */ static const char *harmless_attrs[] = { "parentGUID", NULL }; static int attr_handler2(struct oc_context *ac) { struct ldb_context *ldb; struct ldb_message_element *oc_element; struct ldb_message *msg; const char **must_contain, **may_contain, **found_must_contain; /* There exists a hardcoded delete-protected attributes list in AD */ const char *del_prot_attributes[] = { "nTSecurityDescriptor", "objectSid", "sAMAccountType", "sAMAccountName", "groupType", "primaryGroupID", "userAccountControl", NULL }, **l; const struct dsdb_attribute *attr; unsigned int i; bool found; ldb = ldb_module_get_ctx(ac->module); if (ac->search_res == NULL) { return ldb_operr(ldb); } /* We rely here on the preceding "objectclass" LDB module which did * already fix up the objectclass list (inheritance, order...). */ oc_element = ldb_msg_find_element(ac->search_res->message, "objectClass"); if (oc_element == NULL) { return ldb_operr(ldb); } must_contain = dsdb_full_attribute_list(ac, ac->schema, oc_element, DSDB_SCHEMA_ALL_MUST); may_contain = dsdb_full_attribute_list(ac, ac->schema, oc_element, DSDB_SCHEMA_ALL_MAY); found_must_contain = const_str_list(str_list_copy(ac, must_contain)); if ((must_contain == NULL) || (may_contain == NULL) || (found_must_contain == NULL)) { return ldb_operr(ldb); } /* Check the delete-protected attributes list */ msg = ac->search_res->message; for (l = del_prot_attributes; *l != NULL; l++) { found = str_list_check_ci(must_contain, *l); if (!found) { found = str_list_check_ci(may_contain, *l); } if (found && (ldb_msg_find_element(msg, *l) == NULL)) { ldb_asprintf_errstring(ldb, "objectclass_attrs: delete protected attribute '%s' on entry '%s' missing!", *l, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_UNWILLING_TO_PERFORM; } } /* Check if all specified attributes are valid in the given * objectclasses and if they meet additional schema restrictions. */ for (i = 0; i < msg->num_elements; i++) { attr = dsdb_attribute_by_lDAPDisplayName(ac->schema, msg->elements[i].name); if (attr == NULL) { return ldb_operr(ldb); } /* We can use "str_list_check" with "strcmp" here since the * attribute informations from the schema are always equal * up-down-cased. */ found = str_list_check(must_contain, attr->lDAPDisplayName); if (found) { str_list_remove(found_must_contain, attr->lDAPDisplayName); } else { found = str_list_check(may_contain, attr->lDAPDisplayName); } if (!found) { found = str_list_check(harmless_attrs, attr->lDAPDisplayName); } if (!found) { ldb_asprintf_errstring(ldb, "objectclass_attrs: attribute '%s' on entry '%s' does not exist in the specified objectclasses!", msg->elements[i].name, ldb_dn_get_linearized(msg->dn)); return LDB_ERR_OBJECT_CLASS_VIOLATION; } } if (found_must_contain[0] != NULL) { ldb_asprintf_errstring(ldb, "objectclass_attrs: at least one mandatory attribute ('%s') on entry '%s' wasn't specified!", found_must_contain[0], ldb_dn_get_linearized(msg->dn)); return LDB_ERR_OBJECT_CLASS_VIOLATION; } return ldb_module_done(ac->req, ac->mod_ares->controls, ac->mod_ares->response, LDB_SUCCESS); } static int get_search_callback(struct ldb_request *req, struct ldb_reply *ares) { struct ldb_context *ldb; struct oc_context *ac; int ret; ac = talloc_get_type(req->context, struct oc_context); ldb = ldb_module_get_ctx(ac->module); if (!ares) { return ldb_module_done(ac->req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR); } if (ares->error != LDB_SUCCESS) { return ldb_module_done(ac->req, ares->controls, ares->response, ares->error); } ldb_reset_err_string(ldb); switch (ares->type) { case LDB_REPLY_ENTRY: if (ac->search_res != NULL) { ldb_set_errstring(ldb, "Too many results"); talloc_free(ares); return ldb_module_done(ac->req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR); } ac->search_res = talloc_steal(ac, ares); break; case LDB_REPLY_REFERRAL: /* ignore */ talloc_free(ares); break; case LDB_REPLY_DONE: talloc_free(ares); ret = attr_handler2(ac); if (ret != LDB_SUCCESS) { return ldb_module_done(ac->req, NULL, NULL, ret); } break; } return LDB_SUCCESS; } static int oc_op_callback(struct ldb_request *req, struct ldb_reply *ares) { struct oc_context *ac; struct ldb_context *ldb; struct ldb_request *search_req; struct ldb_dn *base_dn; int ret; ac = talloc_get_type(req->context, struct oc_context); ldb = ldb_module_get_ctx(ac->module); if (!ares) { return ldb_module_done(ac->req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR); } if (ares->type == LDB_REPLY_REFERRAL) { return ldb_module_send_referral(ac->req, ares->referral); } if (ares->error != LDB_SUCCESS) { return ldb_module_done(ac->req, ares->controls, ares->response, ares->error); } if (ares->type != LDB_REPLY_DONE) { talloc_free(ares); return ldb_module_done(ac->req, NULL, NULL, LDB_ERR_OPERATIONS_ERROR); } ac->search_res = NULL; ac->mod_ares = talloc_steal(ac, ares); /* This looks up all attributes of our just added/modified entry */ base_dn = ac->req->operation == LDB_ADD ? ac->req->op.add.message->dn : ac->req->op.mod.message->dn; ret = ldb_build_search_req(&search_req, ldb, ac, base_dn, LDB_SCOPE_BASE, "(objectClass=*)", NULL, NULL, ac, get_search_callback, ac->req); LDB_REQ_SET_LOCATION(search_req); if (ret != LDB_SUCCESS) { return ldb_module_done(ac->req, NULL, NULL, ret); } ret = ldb_request_add_control(search_req, LDB_CONTROL_SHOW_RECYCLED_OID, true, NULL); if (ret != LDB_SUCCESS) { return ldb_module_done(ac->req, NULL, NULL, ret); } ret = ldb_next_request(ac->module, search_req); if (ret != LDB_SUCCESS) { return ldb_module_done(ac->req, NULL, NULL, ret); } /* "ldb_module_done" isn't called here since we need to do additional * checks. It is called at the end of "attr_handler2". */ return LDB_SUCCESS; } static int objectclass_attrs_add(struct ldb_module *module, struct ldb_request *req) { struct ldb_context *ldb; struct oc_context *ac; ldb = ldb_module_get_ctx(module); ldb_debug(ldb, LDB_DEBUG_TRACE, "objectclass_attrs_add\n"); /* do not manipulate our control entries */ if (ldb_dn_is_special(req->op.add.message->dn)) { return ldb_next_request(module, req); } ac = oc_init_context(module, req); if (ac == NULL) { return ldb_operr(ldb); } /* without schema, there isn't much to do here */ if (ac->schema == NULL) { talloc_free(ac); return ldb_next_request(module, req); } return attr_handler(ac); } static int objectclass_attrs_modify(struct ldb_module *module, struct ldb_request *req) { struct ldb_context *ldb; struct oc_context *ac; ldb = ldb_module_get_ctx(module); ldb_debug(ldb, LDB_DEBUG_TRACE, "objectclass_attrs_modify\n"); /* do not manipulate our control entries */ if (ldb_dn_is_special(req->op.mod.message->dn)) { return ldb_next_request(module, req); } ac = oc_init_context(module, req); if (ac == NULL) { return ldb_operr(ldb); } /* without schema, there isn't much to do here */ if (ac->schema == NULL) { talloc_free(ac); return ldb_next_request(module, req); } return attr_handler(ac); } static const struct ldb_module_ops ldb_objectclass_attrs_module_ops = { .name = "objectclass_attrs", .add = objectclass_attrs_add, .modify = objectclass_attrs_modify }; int ldb_objectclass_attrs_module_init(const char *version) { LDB_MODULE_CHECK_VERSION(version); return ldb_register_module(&ldb_objectclass_attrs_module_ops); }