diff --git a/ChangeLog b/ChangeLog
index 5ea79f136..3d8ba00e4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-12  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* include/grub/crypto.h: Add maximums on hash size and cipher block
+	size.
+
 2013-11-12  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/commands/xnu_uuid.c: Remove variable length arrays.
diff --git a/include/grub/crypto.h b/include/grub/crypto.h
index 0e8820ed6..d7ba697c6 100644
--- a/include/grub/crypto.h
+++ b/include/grub/crypto.h
@@ -85,6 +85,10 @@ enum gcry_cipher_modes
   };
 #endif
 
+/* Don't rely on this. Check!  */
+#define GRUB_CRYPTO_MAX_MDLEN 64
+#define GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE 16
+
 /* Type for the cipher_setkey function.  */
 typedef gcry_err_code_t (*gcry_cipher_setkey_t) (void *c,
 						 const unsigned char *key,