# Hexadecimal to binary conversion
def hex2bin(s):
	mp = {'0': "0000",
		'1': "0001",
		'2': "0010",
		'3': "0011",
		'4': "0100",
		'5': "0101",
		'6': "0110",
		'7': "0111",
		'8': "1000",
		'9': "1001",
		'A': "1010",
		'B': "1011",
		'C': "1100",
		'D': "1101",
		'E': "1110",
		'F': "1111"}
	bin = ""
	for i in range(len(s)):
		bin = bin + mp[s[i]]
	return bin

# Binary to hexadecimal conversion


def bin2hex(s):
	mp = {"0000": '0',
		"0001": '1',
		"0010": '2',
		"0011": '3',
		"0100": '4',
		"0101": '5',
		"0110": '6',
		"0111": '7',
		"1000": '8',
		"1001": '9',
		"1010": 'A',
		"1011": 'B',
		"1100": 'C',
		"1101": 'D',
		"1110": 'E',
		"1111": 'F'}
	hex = ""
	for i in range(0, len(s), 4):
		ch = ""
		ch = ch + s[i]
		ch = ch + s[i + 1]
		ch = ch + s[i + 2]
		ch = ch + s[i + 3]
		hex = hex + mp[ch]

	return hex

# Binary to decimal conversion


def bin2dec(binary):

	binary1 = binary
	decimal, i, n = 0, 0, 0
	while(binary != 0):
		dec = binary % 10
		decimal = decimal + dec * pow(2, i)
		binary = binary//10
		i += 1
	return decimal

# Decimal to binary conversion


def dec2bin(num):
	res = bin(num).replace("0b", "")
	if(len(res) % 4 != 0):
		div = len(res) / 4
		div = int(div)
		counter = (4 * (div + 1)) - len(res)
		for i in range(0, counter):
			res = '0' + res
	return res

# Permute function to rearrange the bits


def permute(k, arr, n):
	permutation = ""
	for i in range(0, n):
		permutation = permutation + k[arr[i] - 1]
	return permutation

# shifting the bits towards left by nth shifts


def shift_left(k, nth_shifts):
	s = ""
	for i in range(nth_shifts):
		for j in range(1, len(k)):
			s = s + k[j]
		s = s + k[0]
		k = s
		s = ""
	return k

# calculating xow of two strings of binary number a and b


def xor(a, b):
	ans = ""
	for i in range(len(a)):
		if a[i] == b[i]:
			ans = ans + "0"
		else:
			ans = ans + "1"
	return ans


# Table of Position of 64 bits at initial level: Initial Permutation Table
initial_perm = [58, 50, 42, 34, 26, 18, 10, 2,
				60, 52, 44, 36, 28, 20, 12, 4,
				62, 54, 46, 38, 30, 22, 14, 6,
				64, 56, 48, 40, 32, 24, 16, 8,
				57, 49, 41, 33, 25, 17, 9, 1,
				59, 51, 43, 35, 27, 19, 11, 3,
				61, 53, 45, 37, 29, 21, 13, 5,
				63, 55, 47, 39, 31, 23, 15, 7]

# Expansion D-box Table
exp_d = [32, 1, 2, 3, 4, 5, 4, 5,
		6, 7, 8, 9, 8, 9, 10, 11,
		12, 13, 12, 13, 14, 15, 16, 17,
		16, 17, 18, 19, 20, 21, 20, 21,
		22, 23, 24, 25, 24, 25, 26, 27,
		28, 29, 28, 29, 30, 31, 32, 1]

# Straight Permutation Table
per = [16, 7, 20, 21,
	29, 12, 28, 17,
	1, 15, 23, 26,
	5, 18, 31, 10,
	2, 8, 24, 14,
	32, 27, 3, 9,
	19, 13, 30, 6,
	22, 11, 4, 25]

# S-box Table
sbox = [[[14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7],
		[0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8],
		[4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0],
		[15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13]],

		[[15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10],
		[3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5],
		[0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15],
		[13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9]],

		[[10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8],
		[13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1],
		[13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7],
		[1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12]],

		[[7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15],
		[13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9],
		[10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4],
		[3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14]],

		[[2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9],
		[14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6],
		[4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14],
		[11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3]],

		[[12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11],
		[10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8],
		[9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6],
		[4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13]],

		[[4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1],
		[13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6],
		[1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2],
		[6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12]],

		[[13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7],
		[1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2],
		[7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8],
		[2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11]]]

# Final Permutation Table
final_perm = [40, 8, 48, 16, 56, 24, 64, 32,
			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]

def splitStr(string, length):
    return ' '.join(string[i:i+length] for i in range(0,len(string),length))

def encrypt(pt, rkb, rk):
    pt = hex2bin(pt)
    print(splitStr(pt,4))
    

    # Initial Permutation
    pt = permute(pt, initial_perm, 64)
    print("After initial permutation", bin2hex(pt))
    print(splitStr(pt,4))

    # Splitting
    left = pt[0:32]
    right = pt[32:64]
    for i in range(0, 16):
            # Expansion D-box: Expanding the 32 bits data into 48 bits
            right_expanded = permute(right, exp_d, 48)

            # XOR RoundKey[i] and right_expanded
            xor_x = xor(right_expanded, rkb[i])

            # S-boxex: substituting the value from s-box table by calculating row and column
            sbox_str = ""
            for j in range(0, 8):
                    row = bin2dec(int(xor_x[j * 6] + xor_x[j * 6 + 5]))
                    col = bin2dec(
                            int(xor_x[j * 6 + 1] + xor_x[j * 6 + 2] + xor_x[j * 6 + 3] + xor_x[j * 6 + 4]))
                    val = sbox[j][row][col]
                    sbox_str = sbox_str + dec2bin(val)

            # Straight D-box: After substituting rearranging the bits
            sbox_str = permute(sbox_str, per, 32)

            # XOR left and sbox_str
            result = xor(left, sbox_str)
            left = result

            # Swapper
            if(i != 15):
                    left, right = right, left
            print("Round ", i + 1, " ", bin2hex(left),
                    " ", bin2hex(right), " ", rk[i])

    # Combination
    combine = left + right

    # Final permutation: final rearranging of bits to get cipher text
    cipher_text = permute(combine, final_perm, 64)
    return cipher_text


pt = "123456ABCD132536"
key = "AABB09182736CCDD"
pt = "BADFACE2FACE4DAD"
key = "01234567DEADCAFE"
# Key generation
# --hex to binary
key = hex2bin(key)

# --parity bit drop table
keyp = [57, 49, 41, 33, 25, 17, 9,
		1, 58, 50, 42, 34, 26, 18,
		10, 2, 59, 51, 43, 35, 27,
		19, 11, 3, 60, 52, 44, 36,
		63, 55, 47, 39, 31, 23, 15,
		7, 62, 54, 46, 38, 30, 22,
		14, 6, 61, 53, 45, 37, 29,
		21, 13, 5, 28, 20, 12, 4]

# getting 56 bit key from 64 bit using the parity bits
key = permute(key, keyp, 56)

# Number of bit shifts
shift_table = [1, 1, 2, 2,
			2, 2, 2, 2,
			1, 2, 2, 2,
			2, 2, 2, 1]

# Key- Compression Table : Compression of key from 56 bits to 48 bits
key_comp = [14, 17, 11, 24, 1, 5,
			3, 28, 15, 6, 21, 10,
			23, 19, 12, 4, 26, 8,
			16, 7, 27, 20, 13, 2,
			41, 52, 31, 37, 47, 55,
			30, 40, 51, 45, 33, 48,
			44, 49, 39, 56, 34, 53,
			46, 42, 50, 36, 29, 32]

# Splitting
left = key[0:28] # rkb for RoundKeys in binary
right = key[28:56] # rk for RoundKeys in hexadecimal

rkb = []
rk = []
for i in range(0, 16):
	# Shifting the bits by nth shifts by checking from shift table
	left = shift_left(left, shift_table[i])
	right = shift_left(right, shift_table[i])

	# Combination of left and right string
	combine_str = left + right

	# Compression of key from 56 to 48 bits
	round_key = permute(combine_str, key_comp, 48)

	rkb.append(round_key)
	rk.append(bin2hex(round_key))

print("Encryption")
cipher_text = bin2hex(encrypt(pt, rkb, rk))
print("Cipher Text : ", cipher_text)

print("Decryption")
rkb_rev = rkb[::-1]
rk_rev = rk[::-1]
text = bin2hex(encrypt(cipher_text, rkb_rev, rk_rev))
print("Plain Text : ", text)

# This code is contributed by Aditya Jain