diff --git a/include/mbedtls/cmac.h b/include/mbedtls/cmac.h
index a0563b1..65c831c 100644
--- a/include/mbedtls/cmac.h
+++ b/include/mbedtls/cmac.h
@@ -25,6 +25,7 @@
 
 #ifndef MBEDTLS_CMAC_H
 #define MBEDTLS_CMAC_H
+#include "mbedtls/private_access.h"
 
 #if !defined(MBEDTLS_CONFIG_FILE)
 #include "mbedtls/config.h"
@@ -55,14 +56,14 @@
 struct mbedtls_cmac_context_t
 {
     /** The internal state of the CMAC algorithm.  */
-    unsigned char       state[MBEDTLS_CIPHER_BLKSIZE_MAX];
+    unsigned char       MBEDTLS_PRIVATE(state)[MBEDTLS_CIPHER_BLKSIZE_MAX];
 
     /** Unprocessed data - either data that was not block aligned and is still
      *  pending processing, or the final block. */
-    unsigned char       unprocessed_block[MBEDTLS_CIPHER_BLKSIZE_MAX];
+    unsigned char       MBEDTLS_PRIVATE(unprocessed_block)[MBEDTLS_CIPHER_BLKSIZE_MAX];
 
     /** The length of data pending processing. */
-    size_t              unprocessed_len;
+    size_t              MBEDTLS_PRIVATE(unprocessed_len);
 };
 
 #else  /* !MBEDTLS_CMAC_ALT */