s4-dsdb: Moved some helper functions to a separate file

We need these to be accessible to the aclread module as well.

1 files changed, 255 insertions, 0 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/acl_util.c b/source4/dsdb/samdb/ldb_modules/acl_util.c
new file mode 100644
index 0000000000..27d7fa8cdd
--- /dev/null
+++ b/source4/dsdb/samdb/ldb_modules/acl_util.c
@@ -0,0 +1,255 @@
+/*
+  ACL utility functions
+
+  Copyright (C) Nadezhda Ivanova 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 General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ *  Name: acl_util
+ *
+ *  Component: ldb ACL modules
+ *
+ *  Description: Some auxiliary functions used for access checking
+ *
+ *  Author: Nadezhda Ivanova
+ */
+#include "includes.h"
+#include "ldb_module.h"
+#include "auth/auth.h"
+#include "libcli/security/security.h"
+#include "dsdb/samdb/samdb.h"
+#include "librpc/gen_ndr/ndr_security.h"
+#include "param/param.h"
+#include "dsdb/samdb/ldb_modules/util.h"
+
+struct security_token *acl_user_token(struct ldb_module *module)
+{
+	struct ldb_context *ldb = ldb_module_get_ctx(module);
+	struct auth_session_info *session_info
+		= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
+	if(!session_info) {
+		return NULL;
+	}
+	return session_info->security_token;
+}
+
+/* performs an access check from inside the module stack
+ * given the dn of the object to be checked, the required access
+ * guid is either the guid of the extended right, or NULL
+ */
+
+int dsdb_module_check_access_on_dn(struct ldb_module *module,
+				   TALLOC_CTX *mem_ctx,
+				   struct ldb_dn *dn,
+				   uint32_t access,
+				   const struct GUID *guid)
+{
+	int ret;
+	struct ldb_result *acl_res;
+	static const char *acl_attrs[] = {
+		"nTSecurityDescriptor",
+		"objectSid",
+		NULL
+	};
+	struct ldb_context *ldb = ldb_module_get_ctx(module);
+	struct auth_session_info *session_info
+		= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
+	if(!session_info) {
+		return ldb_operr(ldb);
+	}
+	ret = dsdb_module_search_dn(module, mem_ctx, &acl_res, dn,
+				    acl_attrs,
+				    DSDB_FLAG_NEXT_MODULE |
+				    DSDB_SEARCH_SHOW_DELETED);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,("access_check: failed to find object %s\n", ldb_dn_get_linearized(dn)));
+		return ret;
+	}
+	return dsdb_check_access_on_dn_internal(ldb, acl_res,
+						mem_ctx,
+						session_info->security_token,
+						dn,
+						access,
+						guid);
+}
+
+int acl_check_access_on_attribute(struct ldb_module *module,
+				  TALLOC_CTX *mem_ctx,
+				  struct security_descriptor *sd,
+				  struct dom_sid *rp_sid,
+				  uint32_t access,
+				  const struct dsdb_attribute *attr)
+{
+	int ret;
+	NTSTATUS status;
+	uint32_t access_granted;
+	struct object_tree *root = NULL;
+	struct object_tree *new_node = NULL;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	struct security_token *token = acl_user_token(module);
+	if (attr) {
+		if (!GUID_all_zero(&attr->attributeSecurityGUID)) {
+			if (!insert_in_object_tree(tmp_ctx,
+						   &attr->attributeSecurityGUID, access,
+						   &root, &new_node)) {
+				DEBUG(10, ("acl_search: cannot add to object tree securityGUID\n"));
+				goto fail;
+			}
+
+			if (!insert_in_object_tree(tmp_ctx,
+						   &attr->schemaIDGUID, access, &new_node, &new_node)) {
+				DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
+				goto fail;
+			}
+		}
+		else {
+			if (!insert_in_object_tree(tmp_ctx,
+						   &attr->schemaIDGUID, access, &root, &new_node)) {
+				DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
+				goto fail;
+			}
+		}
+	}
+	status = sec_access_check_ds(sd, token,
+				     access,
+				     &access_granted,
+				     root,
+				     rp_sid);
+	if (!NT_STATUS_IS_OK(status)) {
+		ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
+	}
+	else {
+		ret = LDB_SUCCESS;
+	}
+	talloc_free(tmp_ctx);
+	return ret;
+fail:
+	talloc_free(tmp_ctx);
+	return ldb_operr(ldb_module_get_ctx(module));
+}
+
+int acl_check_access_on_class(struct ldb_module *module,
+			      const struct dsdb_schema *schema,
+			      TALLOC_CTX *mem_ctx,
+			      struct security_descriptor *sd,
+			      struct dom_sid *rp_sid,
+			      uint32_t access,
+			      const char *class_name)
+{
+	int ret;
+	NTSTATUS status;
+	uint32_t access_granted;
+	struct object_tree *root = NULL;
+	struct object_tree *new_node = NULL;
+	const struct GUID *guid;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	struct security_token *token = acl_user_token(module);
+	if (class_name) {
+		guid = class_schemaid_guid_by_lDAPDisplayName(schema, class_name);
+		if (!guid) {
+			DEBUG(10, ("acl_search: cannot find class %s\n",
+				   class_name));
+			goto fail;
+		}
+		if (!insert_in_object_tree(tmp_ctx,
+					   guid, access,
+					   &root, &new_node)) {
+			DEBUG(10, ("acl_search: cannot add to object tree guid\n"));
+			goto fail;
+		}
+	}
+	status = sec_access_check_ds(sd, token,
+				     access,
+				     &access_granted,
+				     root,
+				     rp_sid);
+	if (!NT_STATUS_IS_OK(status)) {
+		ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
+	}
+	else {
+		ret = LDB_SUCCESS;
+	}
+	return ret;
+fail:
+	return ldb_operr(ldb_module_get_ctx(module));
+}
+
+const struct GUID *get_oc_guid_from_message(struct ldb_module *module,
+						   const struct dsdb_schema *schema,
+						   struct ldb_message *msg)
+{
+	struct ldb_message_element *oc_el;
+
+	oc_el = ldb_msg_find_element(msg, "objectClass");
+	if (!oc_el) {
+		return NULL;
+	}
+
+	return class_schemaid_guid_by_lDAPDisplayName(schema,
+						      (char *)oc_el->values[oc_el->num_values-1].data);
+}
+
+
+/* checks for validated writes */
+int acl_check_extended_right(TALLOC_CTX *mem_ctx,
+			     struct security_descriptor *sd,
+			     struct security_token *token,
+			     const char *ext_right,
+			     uint32_t right_type,
+			     struct dom_sid *sid)
+{
+	struct GUID right;
+	NTSTATUS status;
+	uint32_t access_granted;
+	struct object_tree *root = NULL;
+	struct object_tree *new_node = NULL;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+
+	GUID_from_string(ext_right, &right);
+
+	if (!insert_in_object_tree(tmp_ctx, &right, right_type,
+				   &root, &new_node)) {
+		DEBUG(10, ("acl_ext_right: cannot add to object tree\n"));
+		talloc_free(tmp_ctx);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	status = sec_access_check_ds(sd, token,
+				     right_type,
+				     &access_granted,
+				     root,
+				     sid);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		talloc_free(tmp_ctx);
+		return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
+	}
+	talloc_free(tmp_ctx);
+	return LDB_SUCCESS;
+}
+
+const char *acl_user_name(TALLOC_CTX *mem_ctx, struct ldb_module *module)
+{
+	struct ldb_context *ldb = ldb_module_get_ctx(module);
+	struct auth_session_info *session_info
+		= (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
+	if (!session_info) {
+		return "UNKNOWN (NULL)";
+	}
+
+	return talloc_asprintf(mem_ctx, "%s\\%s",
+			       session_info->server_info->domain_name,
+			       session_info->server_info->account_name);
+}