def FK(word, sub_key):
leftBlock = word[0:4]
rightBlock = word[4:]
expension_p = expension_permutation(rightBlock)
helper.debug(["SubKEY", sub_key])
helper.debug(["E/P", expension_p])
for i in range(0,2) :
for j in range(0,4) :
expension_p[i][j] = xor(expension_p[i][j],sub_key[i*4+j])
helper.debug(["XOR(KEY1 and E/EP)", expension_p])
sboxResult = sbox(expension_p)
helper.debug(["sboxResult", sboxResult])
sboxResult = helper.mask_permutation(sboxResult, [1, 3, 2, 0])
helper.debug(["LeftBloc", leftBlock])
helper.debug(["P4", sboxResult])
for j in range(0, 4):
sboxResult[j] = xor(sboxResult[j], leftBlock[j])
helper.debug(["XOR P4", sboxResult])
return sboxResult + rightBlock
def PC2(key):
PC2Mask = [
13, 16, 10, 23, 0, 4, 2, 27, 14, 5, 20, 9, 22, 18, 11, 3, 25, 7, 15, 6,
26, 19, 12, 1, 40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47, 43, 48,
38, 55, 33, 52, 45, 41, 49, 35, 28, 31
]
return helper.mask_permutation(key, PC2Mask)
def PC1(key):
PC1Mask = [
56, 48, 40, 32, 24, 16, 8, 0, 57, 49, 41, 33, 25, 17, 9, 1, 58, 50, 42,
34, 26, 18, 10, 2, 59, 51, 43, 35, 62, 54, 46, 38, 30, 22, 14, 6, 61,
53, 45, 37, 29, 21, 13, 5, 60, 52, 44, 36, 28, 20, 12, 4, 27, 19, 11, 3
]
return helper.mask_permutation(key, PC1Mask)
def IP1(plainText):
ip1Mask = [
39, 7, 47, 15, 55, 23, 63, 31, 38, 6, 46, 14, 54, 22, 62, 30, 37, 5,
45, 13, 53, 21, 61, 29, 36, 4, 44, 12, 52, 20, 60, 28, 35, 3, 43, 11,
51, 19, 59, 27, 34, 2, 42, 10, 50, 18, 58, 26, 33, 1, 41, 9, 49, 17,
57, 25, 32, 0, 40, 8, 48, 16, 56, 24
]
return helper.mask_permutation(plainText, ip1Mask)
def expension_permutation(plainText):
expension_table = [
31, 0, 1, 2, 3, 4, 3, 4, 5, 6, 7, 8, 7, 8, 9, 10, 11, 12, 11, 12, 13,
14, 15, 16, 15, 16, 17, 18, 19, 20, 19, 20, 21, 22, 23, 24, 23, 24, 25,
26, 27, 28, 27, 28, 29, 30, 31, 0
]
expension_mask_applied = helper.mask_permutation(plainText,
expension_table)
# prepare expensions to Sboxs
expension = []
for i in range(0, 8):
expension.insert(i, expension_mask_applied[6 * i:6 * i + 6])
return expension
def FK(word, sub_key):
leftBlock = word[0:32]
rightBlock = word[32:]
############# EXPENSION PERMUATION ###########
expension_p = expension_permutation(rightBlock)
helper.debug(["SubKEY", sub_key])
helper.debug(["E/P", expension_p])
for i in range(0, 8):
for j in range(0, 6):
expension_p[i][j] = xor(expension_p[i][j], sub_key[i * 6 + j])
helper.debug(["XOR(KEY1 and E/EP)", expension_p])
############# XBOX ###############
sboxResult = sbox(expension_p)
helper.debug(["sboxResult", sboxResult])
############ PERmutation P ##########
sboxResultPermutation = helper.mask_permutation(sboxResult, p)
helper.debug(["LeftBloc", leftBlock])
helper.debug(["P", sboxResultPermutation])
############ XOR ############
for j in range(0, 32):
sboxResultPermutation[j] = xor(sboxResultPermutation[j], leftBlock[j])
helper.debug(["XOR LEFT and P", sboxResultPermutation])
return rightBlock + sboxResultPermutation
def IP(plainText):
return helper.mask_permutation(plainText, [1, 5, 2, 0, 3, 7, 4, 6])
def IP_1(plainText):
return helper.mask_permutation(plainText, [3, 0, 2, 4, 6, 1, 7, 5])
def p10_first_permutation(p10key):
P10mask = [2, 4, 1, 6, 3, 9, 0, 8, 7, 5]
return helper.mask_permutation(p10key, P10mask)
def P10_to_P8(key):
P8mask = [5, 2, 6, 3, 7, 4, 9, 8]
return helper.mask_permutation(key, P8mask)
def expension_permutation (plainText) :
expension =[]
expension.insert(0, helper.mask_permutation(plainText[0:4], [3, 0, 1, 2]))
expension.insert(1, helper.mask_permutation(plainText[0:4], [1, 2, 3, 0]))
return expension
