diff --git a/src/signature.h b/src/signature.h
new file mode 100644
--- /dev/null
+++ b/src/signature.h
@@ -0,0 +1,15 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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, version 2.
+ * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file signature.h Routines to validate signature files. */
+
+#ifndef SIGNATURE_H
+#define SIGNATURE_H
+
+bool ValidateSignatureFile(const std::string &filename);
+
+#endif /* SIGNATURE_H */