diff --git a/sys/crypto/chacha20/_chacha.h b/sys/crypto/chacha20/_chacha.h
new file mode 100644
index 000000000000..a7217b628d0e
--- /dev/null
+++ b/sys/crypto/chacha20/_chacha.h
@@ -0,0 +1,12 @@
+/* $FreeBSD$ */
+
+#ifndef _CHACHA_H
+#define _CHACHA_H
+
+#include <sys/types.h>
+
+struct chacha_ctx {
+	u_int input[16];
+};
+
+#endif
diff --git a/sys/crypto/chacha20/chacha.h b/sys/crypto/chacha20/chacha.h
index e67cc81264cd..d150093c6f93 100644
--- a/sys/crypto/chacha20/chacha.h
+++ b/sys/crypto/chacha20/chacha.h
@@ -1,38 +1,35 @@
 /* $OpenBSD: chacha.h,v 1.4 2016/08/27 04:04:56 guenther Exp $ */
 
 /*
 chacha-merged.c version 20080118
 D. J. Bernstein
 Public domain.
 
  $FreeBSD$
 */
 
 #ifndef CHACHA_H
 #define CHACHA_H
 
 #include <sys/types.h>
-
-struct chacha_ctx {
-	u_int input[16];
-};
+#include <crypto/chacha20/_chacha.h>
 
 #define CHACHA_MINKEYLEN 	16
 #define CHACHA_NONCELEN		8
 #define CHACHA_CTRLEN		8
 #define CHACHA_STATELEN		(CHACHA_NONCELEN+CHACHA_CTRLEN)
 #define CHACHA_BLOCKLEN		64
 
 #ifdef _KERNEL
 #define LOCAL
 #else
 #define LOCAL static
 #endif
 
 LOCAL void chacha_keysetup(struct chacha_ctx *x, const u_char *k, u_int kbits);
 LOCAL void chacha_ivsetup(struct chacha_ctx *x, const u_char *iv, const u_char *ctr);
 LOCAL void chacha_encrypt_bytes(struct chacha_ctx *x, const u_char *m,
     u_char *c, u_int bytes);
 
 #endif	/* CHACHA_H */