def ShiftRows(inState): rows = toRows(inState) outState = [] for x in range(4): word = narwhal( rows[x] ) for y in range(x): word = rotWord(word) outState.append(word) return toState(outState)
def rotWord(inWord, inv=False): outWord = narwhal( inWord ) if inv: f = outWord.pop() outWord = [f] + outWord else: f = outWord[0] outWord.remove(f) outWord.append(f) return outWord
def InvCipher(inState, key, Nb, Nk, Nr, l=False):
state = narwhal( inState )
w = KeyExpansion(key, Nb=Nb, Nk=Nk, Nr=Nr)
if l:
print "State: " + printState(state)
state = AddRoundKey(state, w[Nr*Nb:(Nr+1)*Nb])
if l:
print "AddRoundKey: " + printState(state)
sleep(1)
rng = range(1, Nr)
rng.reverse()
for x in rng:
if l:
print "ROUND {round}".format(round=str(x))
state = InvShiftRows(state)
if l:
print "InvShiftRows: " + printState(state)
state = InvSubBytes(state)
if l:
print "InvSubBytes: " + printState(state)
state = AddRoundKey(state, w[x*Nb:(x+1)*Nb])
if l:
print "AddRoundKey: " + printState(state)
state = InvMixColumns(state)
if l:
print "InvMixColumns: " + printState(state)
sleep(1)
state = InvShiftRows(state)
if l:
print "\nFINAL ROUND"
print "InvShiftRows: " + printState(state)
state = InvSubBytes(state)
if l:
print "InvSubBytes: " + printState(state)
state = AddRoundKey(state, w[0:Nb])
if l:
print "AddRoundKey (FINAL DECIPHERED TEXT): " + printState(state)
return state
