diff --git a/ctaocrypt/src/hmac.c b/ctaocrypt/src/hmac.c
index f9a8b0adfd..9b03087f4d 100644
--- a/ctaocrypt/src/hmac.c
+++ b/ctaocrypt/src/hmac.c
@@ -487,5 +487,10 @@ static void HmacCaviumSetKey(Hmac* hmac, int type, const byte* key,
 
 #endif /* HAVE_CAVIUM */
 
+int CyaSSL_GetHmacMaxSize(void)
+{
+    return MAX_DIGEST_SIZE;
+}
+
 #endif /* NO_HMAC */
 
diff --git a/cyassl/ctaocrypt/hmac.h b/cyassl/ctaocrypt/hmac.h
index 596d6e4c10..8a71450a7a 100644
--- a/cyassl/ctaocrypt/hmac.h
+++ b/cyassl/ctaocrypt/hmac.h
@@ -147,6 +147,7 @@ CYASSL_API void HmacFinal(Hmac*, byte*);
     CYASSL_API void HmacFreeCavium(Hmac*);
 #endif
 
+CYASSL_API int CyaSSL_GetHmacMaxSize(void);
 
 #ifdef __cplusplus
     } /* extern "C" */