s4-drs: Do not allow system-critical attributes to be RODC filtered

Signed-off-by: Andrew Tridgell <tridge@samba.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/objectclass.c b/source4/dsdb/samdb/ldb_modules/objectclass.c
index 329bd81ae3..e51038d06f 100644
--- a/source4/dsdb/samdb/ldb_modules/objectclass.c
+++ b/source4/dsdb/samdb/ldb_modules/objectclass.c
@@ -378,6 +378,27 @@ static int fix_check_attributes(struct ldb_context *ldb,
 	return LDB_SUCCESS;
 }
 
+/*
+ * return true if msg carries an attributeSchema that is intended to be RODC
+ * filtered but is also a system-critical attribute.
+ */
+static bool check_rodc_critical_attribute(struct ldb_message *msg)
+{
+	uint32_t schemaFlagsEx, searchFlags, rodc_filtered_flags;
+
+	schemaFlagsEx = ldb_msg_find_attr_as_uint(msg, "schemaFlagsEx", 0);
+	searchFlags = ldb_msg_find_attr_as_uint(msg, "searchFlags", 0);
+	rodc_filtered_flags = (SEARCH_FLAG_RODC_ATTRIBUTE | SEARCH_FLAG_CONFIDENTIAL);
+
+	if ((schemaFlagsEx & SCHEMA_FLAG_ATTR_IS_CRITICAL) &&
+		((searchFlags & rodc_filtered_flags) == rodc_filtered_flags)) {
+		return true;
+	} else {
+		return false;
+	}
+}
+
+
 static int objectclass_do_add(struct oc_context *ac);
 
 static int objectclass_add(struct ldb_module *module, struct ldb_request *req)
@@ -404,6 +425,12 @@ static int objectclass_add(struct ldb_module *module, struct ldb_request *req)
 		return LDB_ERR_OBJECT_CLASS_VIOLATION;
 	}
 
+	/* do not allow to mark an attributeSchema as RODC filtered if it
+	 * is system-critical */
+	if (check_rodc_critical_attribute(req->op.add.message)) {
+		return LDB_ERR_UNWILLING_TO_PERFORM;
+	}
+
 	ac = oc_init_context(module, req);
 	if (ac == NULL) {
 		return LDB_ERR_OPERATIONS_ERROR;
@@ -722,6 +749,12 @@ static int objectclass_modify(struct ldb_module *module, struct ldb_request *req
 		return LDB_ERR_UNWILLING_TO_PERFORM;
 	}
 
+	/* do not allow to mark an attributeSchema as RODC filtered if it
+	 * is system-critical */
+	if (check_rodc_critical_attribute(req->op.mod.message)) {
+		return LDB_ERR_UNWILLING_TO_PERFORM;
+	}
+
 	ac = oc_init_context(module, req);
 	if (ac == NULL) {
 		ldb_oom(ldb);