From bca53f92f18a5e41fdfcf86281b37f60d90b8c5a Mon Sep 17 00:00:00 2001
From: Frank Morgner <morgner@informatik.hu-berlin.de>
Date: Mon, 18 May 2015 07:28:24 +0200
Subject: [PATCH] import Crypto only when needed

---
 virtualsmartcard/src/vpicc/virtualsmartcard/CryptoUtils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/virtualsmartcard/src/vpicc/virtualsmartcard/CryptoUtils.py b/virtualsmartcard/src/vpicc/virtualsmartcard/CryptoUtils.py
index 9203d9c..aac9901 100644
--- a/virtualsmartcard/src/vpicc/virtualsmartcard/CryptoUtils.py
+++ b/virtualsmartcard/src/vpicc/virtualsmartcard/CryptoUtils.py
@@ -17,7 +17,6 @@
 # virtualsmartcard.  If not, see <http://www.gnu.org/licenses/>.
 #
 import sys, binascii, random, logging
-from Crypto.Cipher import DES3, DES, AES, ARC4#@UnusedImport
 from struct import pack
 from binascii import b2a_hex, a2b_hex
 from random import randint
@@ -264,6 +263,7 @@ def calculate_MAC(session_key, message, iv=CYBERFLEX_IV):
     Cyberflex MAC is the last Block of the input encrypted with DES3-CBC
     """
     
+    from Crypto.Cipher import DES3
     cipher = DES3.new(session_key, DES3.MODE_CBC, iv)
     padded = append_padding(8, message, 0x01)
     block_count = len(padded) / cipher.block_size