[implem-python] Retrait des variables globales de lilliput_tbc

On  peut tout  déduire  de len(tweak)  / len(key)  ;  la seule  raison
d'utiliser autant de constantes en C est que les tableaux se dégradent
en  pointeurs,  donc  c'est  où  les  constantes,  où  une  tétrachiée
d'arguments.

1 files changed, 21 insertions, 40 deletions

diff --git a/python/lilliput_tbc.py b/python/lilliput_tbc.py
index 515a671..0dbfb31 100644
--- a/python/lilliput_tbc.py
+++ b/python/lilliput_tbc.py
@@ -4,17 +4,6 @@
 from constants import BLOCK_BYTES, Sbox
 import multiplications
 
-KEY_BITS = 128
-TWEAK_BITS = 192
-LANE_BITS = 64
-LANE_BYTES = LANE_BITS / 8
-LANES = int((TWEAK_BITS+KEY_BITS) / LANE_BITS)
-
-TWEAKEY_BITS = KEY_BITS + TWEAK_BITS
-KEY_BYTES = int(KEY_BITS / 8)
-TWEAK_BYTES = int(TWEAK_BITS / 8)
-TWEAKEY_BYTES = int(TWEAKEY_BITS / 8)
-
 MultiplyM = multiplications.MultiplyM
 MultiplyM2 = multiplications.MultiplyM2
 MultiplyM3 = multiplications.MultiplyM3
@@ -28,46 +17,38 @@ permutationInv = [13, 9, 14, 8, 10, 11, 12, 15, 4, 5, 3, 1, 2, 6 ,0 ,7]
 ################################################################################
 
 def BuildTweakey(tweak, key) :
-
-    tweakey = [0 for byte in range(0, TWEAKEY_BYTES)]
-    for byte in range(0, TWEAK_BYTES) :
-        tweakey[byte] = tweak[byte]
-
-    for byte in range(0, KEY_BYTES) :
-        tweakey[byte + TWEAK_BYTES] = key[byte]
-
-    return tweakey
+    return tweak+key
 
 #############################
 
+def _lane(TK, j):
+    return TK[j*8:(j+1)*8]
+
 def RoundTweakeySchedule(tweakey) :
+    p = len(tweakey)//8
 
     # Multiplication
-    lanes = [tweakey[word * 8:(word+1) * 8] for word in range(0, LANES)]
-    tweakey_multiplied = []
-    for word in range(0, LANES) :
-        if word == 0 :
-            tweakey_multiplied += list(lanes[0])
-        elif word == 1 :
-            tweakey_multiplied += MultiplyM(lanes[1])
-        elif word == 2 :
-            tweakey_multiplied += MultiplyM2(lanes[2])
-        elif word == 3 :
-            tweakey_multiplied += MultiplyM3(lanes[3])
-        elif word == 4 :
-            tweakey_multiplied += MultiplyMR(lanes[4])
-        elif word == 5 :
-            tweakey_multiplied += MultiplyMR2(lanes[5])
-        elif word == 6 :
-            tweakey_multiplied += MultiplyMR3(lanes[6])
-
-    return tweakey_multiplied ;
+    alphas = (
+        list,                   # Identity.
+        MultiplyM,
+        MultiplyM2,
+        MultiplyM3,
+        MultiplyMR,
+        MultiplyMR2,
+        MultiplyMR3
+    )
+
+    return [
+        byte 
+        for j in range(p)
+        for byte in alphas[j](_lane(tweakey, j)) 
+    ]
 
 
 def SubTweakeyExtract(tweakey, Ci):
     subtweakey = [0 for byte in range(0, 8)]
 
-    for byte in range(0, TWEAKEY_BYTES) :
+    for byte in range(len(tweakey)):
         subtweakey[byte % 8] ^= tweakey[byte]
 
     subtweakey[0] ^= Ci