From 2079a6d110ae12f12497605a03deae6720434a6c Mon Sep 17 00:00:00 2001 From: Nadezhda Ivanova Date: Wed, 8 Dec 2010 12:12:34 +0200 Subject: s4-acl: Changed the mechanism of attribute removal to speed it up. Instead of using ldb_msg_remove_attr, now we are flagging the attributes to be removed, and allocating the new elements array to be returned at once. This seems to decrease the overhead by 50 percent. Autobuild-User: Nadezhda Ivanova Autobuild-Date: Wed Dec 8 12:00:27 CET 2010 on sn-devel-104 --- source4/dsdb/samdb/ldb_modules/acl_read.c | 129 ++++++++++++++++++++---------- 1 file changed, 88 insertions(+), 41 deletions(-) diff --git a/source4/dsdb/samdb/ldb_modules/acl_read.c b/source4/dsdb/samdb/ldb_modules/acl_read.c index 87144f92c4..c7aaf113c7 100644 --- a/source4/dsdb/samdb/ldb_modules/acl_read.c +++ b/source4/dsdb/samdb/ldb_modules/acl_read.c @@ -53,12 +53,22 @@ struct aclread_private { bool enabled; }; +static void aclread_mark_inaccesslible(struct ldb_message_element *el) { + el->flags |= LDB_FLAG_INTERNAL_INACCESSIBLE_ATTRIBUTE; +} + +static bool aclread_is_inaccessible(struct ldb_message_element *el) { + return el->flags & LDB_FLAG_INTERNAL_INACCESSIBLE_ATTRIBUTE; +} + static int aclread_callback(struct ldb_request *req, struct ldb_reply *ares) { struct ldb_context *ldb; struct aclread_context *ac; - int ret; - unsigned int i; + struct ldb_message *ret_msg; + struct ldb_message *msg; + int ret, num_of_attrs = 0; + unsigned int i, k = 0; struct security_descriptor *sd; struct dom_sid *sid = NULL; TALLOC_CTX *tmp_ctx; @@ -76,20 +86,21 @@ static int aclread_callback(struct ldb_request *req, struct ldb_reply *ares) tmp_ctx = talloc_new(ac); switch (ares->type) { case LDB_REPLY_ENTRY: - ret = dsdb_get_sd_from_ldb_message(ldb, tmp_ctx, ares->message, &sd); + msg = ares->message; + ret = dsdb_get_sd_from_ldb_message(ldb, tmp_ctx, msg, &sd); if (ret != LDB_SUCCESS) { DEBUG(10, ("acl_read: cannot get descriptor\n")); ret = LDB_ERR_OPERATIONS_ERROR; goto fail; } - sid = samdb_result_dom_sid(tmp_ctx, ares->message, "objectSid"); + sid = samdb_result_dom_sid(tmp_ctx, msg, "objectSid"); /* get the object instance type */ - instanceType = ldb_msg_find_attr_as_uint(ares->message, + instanceType = ldb_msg_find_attr_as_uint(msg, "instanceType", 0); - if (!ldb_dn_is_null(ares->message->dn) && !(instanceType & INSTANCE_TYPE_IS_NC_HEAD)) + if (!ldb_dn_is_null(msg->dn) && !(instanceType & INSTANCE_TYPE_IS_NC_HEAD)) { /* the object has a parent, so we have to check for visibility */ - struct ldb_dn *parent_dn = ldb_dn_get_parent(tmp_ctx, ares->message->dn); + struct ldb_dn *parent_dn = ldb_dn_get_parent(tmp_ctx, msg->dn); ret = dsdb_module_check_access_on_dn(ac->module, tmp_ctx, parent_dn, @@ -103,61 +114,97 @@ static int aclread_callback(struct ldb_request *req, struct ldb_reply *ares) } } /* for every element in the message check RP */ - i = 0; - while (i < ares->message->num_elements) { + for (i=0; i < msg->num_elements; i++) { const struct dsdb_attribute *attr; + bool is_sd, is_objectsid, is_instancetype; + uint32_t access_mask; attr = dsdb_attribute_by_lDAPDisplayName(ac->schema, - ares->message->elements[i].name); + msg->elements[i].name); if (!attr) { DEBUG(2, ("acl_read: cannot find attribute %s in schema\n", - ares->message->elements[i].name)); + msg->elements[i].name)); ret = LDB_ERR_OPERATIONS_ERROR; goto fail; } + is_sd = ldb_attr_cmp("nTSecurityDescriptor", + msg->elements[i].name) == 0; + is_objectsid = ldb_attr_cmp("objectSid", + msg->elements[i].name) == 0; + is_instancetype = ldb_attr_cmp("instanceType", + msg->elements[i].name) == 0; + /* these attributes were added to perform access checks and must be removed */ + if (is_objectsid && ac->object_sid) { + aclread_mark_inaccesslible(&msg->elements[i]); + continue; + } + if (is_instancetype && ac->instance_type) { + aclread_mark_inaccesslible(&msg->elements[i]); + continue; + } + if (is_sd && ac->sd) { + aclread_mark_inaccesslible(&msg->elements[i]); + continue; + } /* nTSecurityDescriptor is a special case */ - if (ldb_attr_cmp("nTSecurityDescriptor", - ares->message->elements[i].name) == 0) { - if (ac->sd) { - ldb_msg_remove_attr(ares->message, ares->message->elements[i].name); - ret = LDB_SUCCESS; - } - ret = acl_check_access_on_attribute(ac->module, - tmp_ctx, - sd, - sid, - SEC_FLAG_SYSTEM_SECURITY|SEC_STD_READ_CONTROL, - attr); + if (is_sd) { + access_mask = SEC_FLAG_SYSTEM_SECURITY|SEC_STD_READ_CONTROL; } else { - ret = acl_check_access_on_attribute(ac->module, - tmp_ctx, - sd, - sid, - SEC_ADS_READ_PROP, - attr); + access_mask = SEC_ADS_READ_PROP; } - if (ret == LDB_SUCCESS) { - i++; - } else if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) { + ret = acl_check_access_on_attribute(ac->module, + tmp_ctx, + sd, + sid, + access_mask, + attr); + + if (ret == LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS) { /* do not return this entry if attribute is - part of the search filter */ + part of the search filter */ if (dsdb_attr_in_parse_tree(ac->req->op.search.tree, - ares->message->elements[i].name)) { + msg->elements[i].name)) { talloc_free(tmp_ctx); return LDB_SUCCESS; } - ldb_msg_remove_attr(ares->message, ares->message->elements[i].name); - } else { + aclread_mark_inaccesslible(&msg->elements[i]); + } else if (ret != LDB_SUCCESS) { goto fail; } } - if (ac->instance_type) { - ldb_msg_remove_attr(ares->message, "instanceType"); + for (i=0; i < msg->num_elements; i++) { + if (!aclread_is_inaccessible(&msg->elements[i])) { + num_of_attrs++; + } } - if (ac->object_sid) { - ldb_msg_remove_attr(ares->message, "objectSid"); + /*create a new message to return*/ + ret_msg = ldb_msg_new(req); + ret_msg->dn = msg->dn; + ret_msg->num_elements = num_of_attrs; + if (num_of_attrs > 0) { + ret_msg->elements = talloc_array(ret_msg, + struct ldb_message_element, + num_of_attrs); + if (ret_msg->elements == NULL) { + return ldb_oom(ldb); + } + for (i=0; i < msg->num_elements; i++) { + bool to_remove = aclread_is_inaccessible(&msg->elements[i]); + if (!to_remove) { + ret_msg->elements[k] = msg->elements[i]; + if (!talloc_reference(ret_msg->elements, + msg->elements[i].values)) { + talloc_free(tmp_ctx); + return ldb_operr(ldb); + } + k++; + } + } + } else { + ret_msg->elements = NULL; } talloc_free(tmp_ctx); - return ldb_module_send_entry(ac->req, ares->message, ares->controls); + + return ldb_module_send_entry(ac->req, ret_msg, ares->controls); case LDB_REPLY_REFERRAL: return ldb_module_send_referral(ac->req, ares->referral); case LDB_REPLY_DONE: -- cgit