diff --git a/crypto/cast.c b/crypto/cast.c
index 8ad184197a..abfb07f875 100644
--- a/crypto/cast.c
+++ b/crypto/cast.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * crypto/cast.c
  *
- * $OpenBSD: cast.c,v 1.4 2012/04/25 04:12:27 matthew Exp $
+ * SPDX-License-Identifier: NuttX-PublicDomain
  *
  * CAST-128 in C
  * Written by Steve Reid <sreid@sea-to-sky.net>
diff --git a/crypto/castsb.h b/crypto/castsb.h
index 3dd5435041..24ecb8ed76 100644
--- a/crypto/castsb.h
+++ b/crypto/castsb.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * crypto/castsb.h
  *
- * $OpenBSD: castsb.h,v 1.1 2000/02/28 23:13:04 deraadt Exp $
+ * SPDX-License-Identifier: NuttX-PublicDomain
  *
  * CAST-128 in C
  * Written by Steve Reid <sreid@sea-to-sky.net>