Timing; generate roundkeys on initialisation

1 files changed, 12 insertions, 13 deletions

diff --git a/pypride.py b/pypride.py
index 935d8c4..b30b565 100644
--- a/pypride.py
+++ b/pypride.py
@@ -61,13 +61,12 @@ class Pride:
     def __init__(self,key):
         """Create a PRIDE cipher object
 
-        key:    the key as a 128-bit raw string"""
+        Input:  the key as a 128-bit raw string"""
 
-        if len(key) * 8 == 128:
-            self.key_whitening = string2number(key[:8])
-            self.key_1 = key[8:]
-        else:
+        if len(key) != 16:
             raise ValueError, "Key must be a 128-bit raw string"
+        self.whitening_key = string2number(key[:8])
+        self.roundkeys = [roundKey(key[8:], i) for i in xrange(0,21)]
 
     def encrypt(self,block):
         """Encrypt 1 block (8 bytes)
@@ -79,17 +78,17 @@ class Pride:
 
         # Initial permutation & pre-whitening
         state = pLayer_dec(state)
-        state = addRoundKey(state, self.key_whitening)
+        state = addRoundKey(state, self.whitening_key)
         # 19 rounds R
         for i in xrange (1,20):
-            state = addRoundKey(state, roundKey(self.key_1, i))
+            state = addRoundKey(state, self.roundkeys[i])
             state = sBoxLayer(state)
             state = lLayer(state)
         # Last round R'
-        state = addRoundKey(state, roundKey(self.key_1, 20))
+        state = addRoundKey(state, self.roundkeys[20])
         state = sBoxLayer(state)
         # Post-whitening & final permutation
-        state = addRoundKey(state, self.key_whitening)
+        state = addRoundKey(state, self.whitening_key)
         state = pLayer(state)
 
         return number2string_N(state,8)
@@ -104,17 +103,17 @@ class Pride:
 
         # Final permutation & post-whitening
         state = pLayer_dec(state)
-        state = addRoundKey(state, self.key_whitening)
+        state = addRoundKey(state, self.whitening_key)
         # Last round R'
         state = sBoxLayer_dec(state)
-        state = addRoundKey(state, roundKey(self.key_1, 20))
+        state = addRoundKey(state, self.roundkeys[20])
         # 19 rounds R
         for i in xrange(19,0,-1):
             state = lLayer_dec(state)
             state = sBoxLayer_dec(state)
-            state = addRoundKey(state, roundKey(self.key_1, i))
+            state = addRoundKey(state, self.roundkeys[i])
         # Pre-whitening & initial permutation
-        state = addRoundKey(state, self.key_whitening)
+        state = addRoundKey(state, self.whitening_key)
         state = pLayer(state)
 
         return number2string_N(state,8)