Commit 1998890a authored by Luc Libralesso's avatar Luc Libralesso
Browse files

add unit tests for aes192 keyschedule + aes192 tests

parent f8b57f71
#!/usr/bin/python
#
# aes.py: implements AES - Advanced Encryption Standard
# from the SlowAES project, http://code.google.com/p/slowaes/
#
# Copyright (c) 2008 Josh Davis ( http://www.josh-davis.org ),
# Alex Martelli ( http://www.aleax.it )
#
# Ported from C code written by Laurent Haan ( http://www.progressive-coding.com )
#
# Licensed under the Apache License, Version 2.0
# http://www.apache.org/licenses/
#
import os
import sys
import math
class AES(object):
'''AES funtions for a single block
'''
# Very annoying code: all is for an object, but no state is kept!
# Should just be plain functions in a AES modlule.
# valid key sizes
keySize = dict(SIZE_128=16, SIZE_192=24, SIZE_256=32)
# Rijndael S-box
sbox = [0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67,
0x2b, 0xfe, 0xd7, 0xab, 0x76, 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59,
0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 0xb7,
0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1,
0x71, 0xd8, 0x31, 0x15, 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05,
0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83,
0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29,
0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 0xd0, 0xef, 0xaa,
0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c,
0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc,
0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec,
0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19,
0x73, 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee,
0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, 0xe0, 0x32, 0x3a, 0x0a, 0x49,
0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4,
0xea, 0x65, 0x7a, 0xae, 0x08, 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6,
0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, 0x70,
0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9,
0x86, 0xc1, 0x1d, 0x9e, 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e,
0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, 0x8c, 0xa1,
0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0,
0x54, 0xbb, 0x16]
def getSBoxValue(self,num):
"""Retrieves a given S-Box Value"""
return self.sbox[num]
def rotate(self, word):
""" Rijndael's key schedule rotate operation.
Rotate a word eight bits to the left: eg, rotate(1d2c3a4f) == 2c3a4f1d
Word is an char list of size 4 (32 bits overall).
"""
return word[1:] + word[:1]
# Rijndael Rcon
Rcon = [0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97,
0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72,
0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66,
0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04,
0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d,
0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3,
0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61,
0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,
0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40,
0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc,
0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5,
0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a,
0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d,
0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c,
0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35,
0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4,
0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc,
0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08,
0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a,
0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d,
0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2,
0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74,
0xe8, 0xcb ]
def getRconValue(self, num):
"""Retrieves a given Rcon Value"""
return self.Rcon[num]
def core(self, word, iteration):
"""Key schedule core."""
# rotate the 32-bit word 8 bits to the left
word = self.rotate(word)
# apply S-Box substitution on all 4 parts of the 32-bit word
for i in range(4):
word[i] = self.getSBoxValue(word[i])
# XOR the output of the rcon operation with i to the first part
# (leftmost) only
word[0] = word[0] ^ self.getRconValue(iteration)
return word
def expandKey(self, key, size, expandedKeySize):
"""Rijndael's key expansion.
Expands an 128,192,256 key into an 176,208,240 bytes key
expandedKey is a char list of large enough size,
key is the non-expanded key.
"""
print("EXPAND_KEY: key:{}\tsize:{}\texpandedKeySize:{}".format(key,size,expandedKeySize))
# current expanded keySize, in bytes
currentSize = 0
rconIteration = 1
expandedKey = [0] * expandedKeySize
# set the 16, 24, 32 bytes of the expanded key to the input key
for j in range(size):
expandedKey[j] = key[j]
currentSize += size
while currentSize < expandedKeySize:
# assign the previous 4 bytes to the temporary value t
t = expandedKey[currentSize-4:currentSize]
# every 16,24,32 bytes we apply the core schedule to t
# and increment rconIteration afterwards
if currentSize % size == 0:
t = self.core(t, rconIteration)
rconIteration += 1
# For 256-bit keys, we add an extra sbox to the calculation
if size == self.keySize["SIZE_256"] and ((currentSize % size) == 16):
for l in range(4): t[l] = self.getSBoxValue(t[l])
# We XOR t with the four-byte block 16,24,32 bytes before the new
# expanded key. This becomes the next four bytes in the expanded
# key.
for m in range(4):
expandedKey[currentSize] = expandedKey[currentSize - size] ^ \
t[m]
currentSize += 1
print("expandedKey: {}".format(["{}".format(e) for e in expandedKey]))
for i in range(len(expandedKey)/(4*6)):
print(",\t".join([str(e) for e in expandedKey[i*4*6:((i+1)*4*6)]]))
print("expandedKey (nb columns): {}".format(len(expandedKey)/4))
print("rounds covered: {}".format(len(expandedKey)/16))
return expandedKey
def addRoundKey(self, state, roundKey):
"""Adds (XORs) the round key to the state."""
for i in range(16):
state[i] ^= roundKey[i]
return state
def createRoundKey(self, expandedKey, roundKeyPointer):
"""Create a round key.
Creates a round key from the given expanded key and the
position within the expanded key.
"""
roundKey = [0] * 16
for i in range(4):
for j in range(4):
roundKey[j*4+i] = expandedKey[roundKeyPointer + i*4 + j] # correct
# roundKey[j*4+i] = expandedKey[roundKeyPointer + j*4 + i] # incorrect
return roundKey
def galois_multiplication(self, a, b):
"""Galois multiplication of 8 bit characters a and b."""
p = 0
for counter in range(8):
if b & 1: p ^= a
hi_bit_set = a & 0x80
a <<= 1
# keep a 8 bit
a &= 0xFF
if hi_bit_set:
a ^= 0x1b
b >>= 1
return p
#
# substitute all the values from the state with the value in the SBox
# using the state value as index for the SBox
#
def subBytes(self, state, isInv):
if isInv: getter = self.getSBoxInvert
else: getter = self.getSBoxValue
for i in range(16): state[i] = getter(state[i])
return state
# iterate over the 4 rows and call shiftRow() with that row
def shiftRows(self, state, isInv):
for i in range(4):
state = self.shiftRow(state, i*4, i, isInv)
return state
# each iteration shifts the row to the left by 1
def shiftRow(self, state, statePointer, nbr, isInv):
for i in range(nbr):
if isInv:
state[statePointer:statePointer+4] = \
state[statePointer+3:statePointer+4] + \
state[statePointer:statePointer+3]
else:
state[statePointer:statePointer+4] = \
state[statePointer+1:statePointer+4] + \
state[statePointer:statePointer+1]
return state
# galois multiplication of the 4x4 matrix
def mixColumns(self, state, isInv):
# iterate over the 4 columns
for i in range(4):
# construct one column by slicing over the 4 rows
column = state[i:i+16:4]
# apply the mixColumn on one column
column = self.mixColumn(column, isInv)
# put the values back into the state
state[i:i+16:4] = column
return state
# galois multiplication of 1 column of the 4x4 matrix
def mixColumn(self, column, isInv):
if isInv: mult = [14, 9, 13, 11]
else: mult = [2, 1, 1, 3]
cpy = list(column)
g = self.galois_multiplication
column[0] = g(cpy[0], mult[0]) ^ g(cpy[3], mult[1]) ^ \
g(cpy[2], mult[2]) ^ g(cpy[1], mult[3])
column[1] = g(cpy[1], mult[0]) ^ g(cpy[0], mult[1]) ^ \
g(cpy[3], mult[2]) ^ g(cpy[2], mult[3])
column[2] = g(cpy[2], mult[0]) ^ g(cpy[1], mult[1]) ^ \
g(cpy[0], mult[2]) ^ g(cpy[3], mult[3])
column[3] = g(cpy[3], mult[0]) ^ g(cpy[2], mult[1]) ^ \
g(cpy[1], mult[2]) ^ g(cpy[0], mult[3])
return column
# applies the 4 operations of the forward round in sequence
def aes_round(self, state, roundKey):
state = self.subBytes(state, False)
state = self.shiftRows(state, False)
state = self.mixColumns(state, False)
state = self.addRoundKey(state, roundKey)
return state
# Perform the initial operations, the standard round, and the final
# operations of the forward aes, creating a round key for each round
def aes_main(self, state, expandedKey, nbrRounds):
print("RK:\t{}".format("\t,".join([ "0x{:0x}".format(e) for e in self.createRoundKey(expandedKey, 0)])))
state = self.addRoundKey(state, self.createRoundKey(expandedKey, 0))
i = 1
while i < nbrRounds:
print("RK:\t{}".format("\t,".join([ "0x{:0x}".format(e) for e in self.createRoundKey(expandedKey, 16*i)])))
state = self.aes_round(state,
self.createRoundKey(expandedKey, 16*i))
i += 1
state = self.subBytes(state, False)
state = self.shiftRows(state, False)
print("RK:\t{}".format("\t,".join([ "0x{:0x}".format(e) for e in self.createRoundKey(expandedKey, 16*nbrRounds)])))
state = self.addRoundKey(state,
self.createRoundKey(expandedKey, 16*nbrRounds))
return state
# encrypts a 128 bit input block against the given key of size specified
def encrypt(self, iput, key, size):
output = [0] * 16
# the number of rounds
nbrRounds = 0
# the 128 bit block to encode
block = [0] * 16
# set the number of rounds
if size == self.keySize["SIZE_128"]: nbrRounds = 10
elif size == self.keySize["SIZE_192"]: nbrRounds = 12
elif size == self.keySize["SIZE_256"]: nbrRounds = 14
else: return None
# the expanded keySize
expandedKeySize = 16*(nbrRounds+1)
# Set the block values, for the block:
# a0,0 a0,1 a0,2 a0,3
# a1,0 a1,1 a1,2 a1,3
# a2,0 a2,1 a2,2 a2,3
# a3,0 a3,1 a3,2 a3,3
# the mapping order is a0,0 a1,0 a2,0 a3,0 a0,1 a1,1 ... a2,3 a3,3
#
# iterate over the columns
for i in range(4):
# iterate over the rows
for j in range(4):
block[(i+(j*4))] = iput[(i*4)+j]
# expand the key into an 176, 208, 240 bytes key
# the expanded key
expandedKey = self.expandKey(key, size, expandedKeySize)
# encrypt the block using the expandedKey
block = self.aes_main(block, expandedKey, nbrRounds)
# unmap the block again into the output
for k in range(4):
# iterate over the rows
for l in range(4):
output[(k*4)+l] = block[(k+(l*4))]
return output
if __name__ == "__main__":
# encrypt(self, iput, key, size):
aes = AES()
# k = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]
k = [255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255]
# m = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]
m = [255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255]
c = aes.encrypt(m,k,aes.keySize["SIZE_192"])
print(", ".join(["0x{:0x}".format(e) for e in c]))
# moo = AESModeOfOperation()
# cleartext = "This is a test with several blocks!"
# cypherkey = [143,194,34,208,145,203,230,143,177,246,97,206,145,92,255,84 ,145,92,255,84,145,92,255,84]
# iv = [103,35,148,239,76,213,47,118,255,222,123,176,106,134,98,92]
# mode, orig_len, ciph = moo.encrypt(cleartext, moo.modeOfOperation["CBC"],
# cypherkey, moo.aes.keySize["SIZE_192"], iv)
# print 'm=%s, ol=%s (%s), ciph=%s' % (mode, orig_len, len(cleartext), ciph)
# decr = moo.decrypt(ciph, orig_len, mode, cypherkey,
# moo.aes.keySize["SIZE_192"], iv)
# print decr
# testStr(cleartext, 16, "CBC")
......@@ -13,35 +13,32 @@ require_relative '../../nodes/mixcolumn.rb'
require_relative '../../nodes/aeskeyschedule.rb'
def extract_columns(e, i,j)
res = []
(i..j).each do |k|
tmp = []
4.times do |l|
tmp.append(e[l][k])
##
# combine the 2 first columns of m1 starting at x coordinate i1 and the 2 last columns of m2 starting at x coordinate i2
def combine_columns_2h(m1, i1, m2, i2)
matrix = MultiMatrix.build(m1.type, [4,4])
for i in 0..1
4.times do |j|
matrix[j][i] = m1[j][i1+i]
end
res.append(tmp)
end
return res
end
def combine_columns(a,b)
res = []
for e in a
tmp = []
4.times do |i|
tmp.append(e[i])
for i in 0..1
4.times do |j|
matrix[j][i+2] = m2[j][i2+i]
end
res.append(tmp)
end
for e in b
tmp = []
4.times do |i|
tmp.append(e[i])
return matrix
end
def extract_four_first(m1)
matrix = MultiMatrix.build(m1.type, [4,4])
for i in 0..3
4.times do |j|
# matrix[j][i] = m1[j][i]
matrix[i][j] = m1[j][i]
end
res.append(tmp)
end
return res
return matrix
end
......@@ -62,32 +59,41 @@ class AES192_Dag < CryptoDag
nodes.push(@k)
key_nodes = []
key_nodes.push(@k)
for i in 1..(nb_rounds*4/6).ceil-1
kprev = key_nodes[key_nodes.length-1]
k_current = AESKeyScheduleNode.new(name:"K_#{i}", input:kprev.outputs[0], subtable:@sbox, rcon:@rcon[i])
key_nodes.push(k_current)
nodes.push(k_current)
for i in 0..(nb_rounds/1.5).ceil
if i > 0
k_current = AESKeyScheduleNode.new(
name:"K_#{i}",
input:key_nodes[key_nodes.length-1].outputs[0],
subtable:@sbox,rcon:@rcon[i]
)
key_nodes.push(k_current)
nodes.push(k_current)
end
end
# puts "keynodes size: #{key_nodes.length}"
#define internal nodes
addkey = XorNode.new(name:"ARK_0", inputs:[@x.outputs[0],@k.outputs[0]])
# p "##### #{@x.outputs[0].dimensions}\t#{@k.outputs[0].dimensions}"
# addkey = XorNode.new(name:"ARK_0", inputs:[@x.outputs[0],extract_four_first(@k.outputs[0])])
c1 = 0
c2 = 2
addkey = XorNode.new(name:"ARK_0", inputs:[
@x.outputs[0],
combine_columns_2h(
key_nodes[(c1/6).floor].outputs[0], c1%6,
key_nodes[(c2/6).floor].outputs[0], c2%6,
)
])
nodes.push(addkey)
kprev = @k
for i in 1..nb_rounds do
ki = []
for c in (i*4)..(i*4+3)
current_key_block = (c / 6).floor()
current_block_col = c-current_key_block*6
tmp = []
4.times do |j|
tmp.append(key_nodes[current_key_block].outputs[0][j][current_block_col])
end
ki.append(tmp)
end
# dirty hack ahead
ki.define_singleton_method(:dimensions) do
return [4,4]
end
# end
c1 = (i)*4
c2 = (i)*4 + 2
# puts "round #{i}:\tm1:#{(c1/6).floor}\tm2:#{(c2/6).floor}"
ki = combine_columns_2h(
key_nodes[(c1/6).floor].outputs[0], c1%6,
key_nodes[(c2/6).floor].outputs[0], c2%6,
)
# p ki
subbytes = SubBytesNode.new(name:"SB_#{i}", input:addkey.outputs[0], subtable:@sbox)
nodes.push(subbytes)
shiftrows = ShiftRowsNode.new(name:"SR_#{i}", input:subbytes.outputs[0])
......@@ -101,7 +107,7 @@ class AES192_Dag < CryptoDag
addkey = XorNode.new(name:"ARK_#{i}", inputs:[mixcolumns.outputs[0],ki])
nodes.push(addkey)
end
define dag inputs/outputs
# define dag inputs/outputs
super([@x,@k], [addkey], nodes)
end
......
......@@ -25,7 +25,7 @@ class AESKeyScheduleNode < CryptoDagNode
]
4.times do |i|
operators.push(EqualityOperator.new(
input[(i+1) % 4][3], # last column of the input
input[(i+1) % 4][nb_cols-1], # last column of the input
@rotated_bytes[i],
))
end
......@@ -71,12 +71,12 @@ class AESKeyScheduleNode < CryptoDagNode
4.times do |j|
operators.push(SOperator.new(
output[j][index-1],
sub_vars[j],
@sub_vars[j],
@subtable
))
operators.push(XorOperator.new(
input[j][index],
sub_vars[j],
@sub_vars[j],
output[j][index]
))
end
......
#!/usr/bin/ruby
require 'minitest/autorun'
require_relative "../../cryptosystems/aes/aes192.rb"
class TestAES192 < Minitest::Unit::TestCase
def test_construction()
# create DAG
dag = AES192_Dag.new()
# # simulate behavior
output = dag.simulate_behavior(
[ # M
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff]
],
[ # K
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff]
]
)
assert_equal(output, [
191, 41, 228, 187, 112, 255, 141, 129, 3, 113, 223, 116, 78, 142, 54, 239
])
end
end
\ No newline at end of file
#!/usr/bin/ruby
require 'minitest/autorun'
require_relative '../../cryptosystems/aes/aes192.rb'
require_relative '../../cryptosystems/aes/constants.rb'
require_relative '../../cryptodag.rb'
require_relative '../../simulate_cryptodag.rb'
require_relative '../../nodes/input.rb'
require_relative '../../nodes/xor.rb'
require_relative '../../nodes/subbytes.rb'
require_relative '../../nodes/shiftrows.rb'
require_relative '../../nodes/mixcolumn.rb'
require_relative '../../nodes/aeskeyschedule.rb'
class TestAES192 < Minitest::Unit::TestCase
def setup()
@rcon = rcon
@mc = mixcolumns_matrix()
@sbox = s_box()
# define input nodes
@nodes = []
@nb_rounds = 12
@x = InputNode.new(name:"X", dimensions:[4,4])
@nodes.push(@x)
@k = InputNode.new(name:"K", dimensions:[4,6])
@nodes.push(@k)
@key_nodes = []
@key_nodes.push(@k)
for i in 0..(@nb_rounds/1.5).ceil
if i > 0
k_current = AESKeyScheduleNode.new(
name:"K_#{i}",
input:@key_nodes[@key_nodes.length-1].outputs[0],
subtable:@sbox,
rcon:@rcon[i]
)
@key_nodes.push(k_current)
@nodes.push(k_current)
end
end
@input_values = [ # M
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff]
].flatten + [ # K
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
[0xff, 0xff, 0xff, 0xff, 0xff, 0xff]
].flatten
end
def get_round_key(i)
c1 = (i)*4
c2 = (i)*4 + 2
return combine_columns_2h(