1 files changed, 1 insertions, 1 deletions

diff --git a/crypto/src/crypto/macs/CMac.cs b/crypto/src/crypto/macs/CMac.cs

index b55a05605..682c12bac 100644
--- a/crypto/src/crypto/macs/CMac.cs
+++ b/crypto/src/crypto/macs/CMac.cs
@@ -107,7 +107,7 @@ namespace Org.BouncyCastle.Crypto.Macs
 
         private static int ShiftLeft(byte[] block, byte[] output)
         {
-            int i = 16;
+            int i = block.Length;
             uint bit = 0;
             while (--i >= 0)
             {