282 lines
10 KiB
Python
282 lines
10 KiB
Python
# AES
|
|
|
|
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 ]
|
|
|
|
inv_sbox = [ 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB,
|
|
0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB,
|
|
0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E,
|
|
0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25,
|
|
0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92,
|
|
0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84,
|
|
0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06,
|
|
0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B,
|
|
0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73,
|
|
0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E,
|
|
0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B,
|
|
0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4,
|
|
0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F,
|
|
0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF,
|
|
0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
|
|
0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D ]
|
|
|
|
rcon = [ 0x00, 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, ]
|
|
|
|
|
|
|
|
def hex_to_4x4_hex_matrix(hex_string):
|
|
matrix = []
|
|
for i in range(0, len(hex_string), 8):
|
|
matrix.append([int(hex_string[i:i+2], 16), int(hex_string[i+2:i+4], 16), int(hex_string[i+4:i+6], 16), int(hex_string[i+6:i+8], 16)])
|
|
return matrix
|
|
|
|
|
|
def sub_word(word):
|
|
for i in range(4):
|
|
word[i] = sbox[word[i]]
|
|
return word
|
|
|
|
def rot_word(word):
|
|
return word[1:] + word[:1]
|
|
|
|
def key_expansion(key_matrix):
|
|
expanded_key = key_matrix[:]
|
|
for i in range(4, 44):
|
|
temp = expanded_key[i-1]
|
|
if i % 4 == 0:
|
|
temp = sub_word(rot_word(temp))
|
|
temp[0] ^= rcon[i//4]
|
|
expanded_key.append([a ^ b for a, b in zip(expanded_key[i-4], temp)])
|
|
return expanded_key
|
|
|
|
def sub_bytes(state):
|
|
for i in range(4):
|
|
for j in range(4):
|
|
if state[i][j] < 0 or state[i][j] >= len(sbox):
|
|
raise ValueError(f"Invalid value in state: {state[i][j]}")
|
|
state[i][j] = sbox[state[i][j]]
|
|
return state
|
|
|
|
|
|
def shift_rows(state):
|
|
state = [list(row) for row in zip(*state)] # Transpose the state matrix
|
|
for i in range(1, 4):
|
|
state[i] = state[i][i:] + state[i][:i]
|
|
state = [list(row) for row in zip(*state)] # Transpose back to original
|
|
return state
|
|
|
|
def mix_columns(state):
|
|
for i in range(4):
|
|
a = state[i][0]
|
|
b = state[i][1]
|
|
c = state[i][2]
|
|
d = state[i][3]
|
|
state[i][0] = gmul(a, 2) ^ gmul(b, 3) ^ c ^ d
|
|
state[i][1] = a ^ gmul(b, 2) ^ gmul(c, 3) ^ d
|
|
state[i][2] = a ^ b ^ gmul(c, 2) ^ gmul(d, 3)
|
|
state[i][3] = gmul(a, 3) ^ b ^ c ^ gmul(d, 2)
|
|
return state
|
|
|
|
def gmul(a, b):
|
|
p = 0
|
|
for _ in range(8):
|
|
if b & 1:
|
|
p ^= a
|
|
hi_bit_set = a & 0x80
|
|
a <<= 1
|
|
if hi_bit_set:
|
|
a ^= 0x1b
|
|
b >>= 1
|
|
return p & 0xFF
|
|
|
|
def add_round_key(state, round_key):
|
|
for i in range(4):
|
|
for j in range(4):
|
|
state[i][j] ^= round_key[i][j]
|
|
return state
|
|
|
|
def convert_state_to_hex_string(state):
|
|
state_hex = ""
|
|
for col in range(4):
|
|
for row in range(4):
|
|
state_hex += format(state[row][col], '02x')
|
|
return state_hex
|
|
|
|
def count_differing_bits(state1, state2):
|
|
differing_bits = 0
|
|
for row1, row2 in zip(state1, state2):
|
|
for byte1, byte2 in zip(row1, row2):
|
|
differing_bits += bin(byte1 ^ byte2).count('1')
|
|
return differing_bits
|
|
|
|
def encrypt(plaintext, key):
|
|
# Convert plaintext and key to matrix
|
|
plaintext_matrix = hex_to_4x4_hex_matrix(plaintext)
|
|
key_matrix = hex_to_4x4_hex_matrix(key)
|
|
|
|
# Print plaintext and key
|
|
# print("Plaintext:")
|
|
# for row in plaintext_matrix:
|
|
# print(row)
|
|
|
|
# print("\nKey:")
|
|
# for row in key_matrix:
|
|
# print(row)
|
|
|
|
# Key Expansion
|
|
expanded_key = key_expansion(key_matrix)
|
|
# print("\nExpanded Key:", expanded_key)
|
|
|
|
# Initial Round
|
|
state = add_round_key(plaintext_matrix, key_matrix)
|
|
#print("\nInitial Round:")
|
|
# for row in state:
|
|
# print(row)
|
|
|
|
original_state = state
|
|
bits_changed_per_round = []
|
|
|
|
print ("\nInitial Round text:", convert_state_to_hex_string(state))
|
|
# Rounds
|
|
for i in range(9):
|
|
state = sub_bytes(state)
|
|
#print("\nSub Bytes:", convert_state_to_hex_string(state))
|
|
state = shift_rows(state)
|
|
#print("\nShift Rows:", convert_state_to_hex_string(state))
|
|
state = mix_columns(state)
|
|
#print("\nMix Columns:", convert_state_to_hex_string(state))
|
|
state = add_round_key(state, expanded_key[4*(i+1):4*(i+2)])
|
|
print("\nRound", i+1)
|
|
# for row in state:
|
|
# print(row)
|
|
print("Round text:", convert_state_to_hex_string(state))
|
|
|
|
# Avalanche effect
|
|
bits_changed = count_differing_bits(original_state, state)
|
|
bits_changed_per_round.append(bits_changed)
|
|
print("Bits changed due to avalanche effect:", bits_changed)
|
|
|
|
# Final Round
|
|
state = sub_bytes(state)
|
|
# print("\nSub Bytes:", state)
|
|
state = shift_rows(state)
|
|
# print("\nShift Rows:", state)
|
|
state = add_round_key(state, expanded_key[40:])
|
|
print("\nFinal Round:")
|
|
# for row in state:
|
|
# print(row)
|
|
|
|
# Convert state to hex string
|
|
ciphertext = convert_state_to_hex_string(state)
|
|
|
|
print("\nCiphertext:", ciphertext)
|
|
|
|
# Avalanche effect
|
|
bits_changed = count_differing_bits(original_state, state)
|
|
bits_changed_per_round.append(bits_changed)
|
|
print("Bits changed due to avalanche effect:", bits_changed)
|
|
|
|
return ciphertext
|
|
|
|
|
|
def inv_sub_bytes(state):
|
|
for i in range(4):
|
|
for j in range(4):
|
|
if state[i][j] < 0 or state[i][j] >= len(inv_sbox):
|
|
raise ValueError(f"Invalid value in state: {state[i][j]}")
|
|
state[i][j] = inv_sbox[state[i][j]]
|
|
return state
|
|
|
|
def inv_shift_rows(state):
|
|
state = [list(row) for row in zip(*state)] # Transpose the state matrix
|
|
for i in range(1, 4):
|
|
state[i] = state[i][-i:] + state[i][:-i]
|
|
state = [list(row) for row in
|
|
zip(*state)] # Transpose back to original
|
|
return state
|
|
|
|
def inv_mix_columns(state):
|
|
for i in range(4):
|
|
a = state[i][0]
|
|
b = state[i][1]
|
|
c = state[i][2]
|
|
d = state[i][3]
|
|
state[i][0] = gmul(a, 0x0e) ^ gmul(b, 0x0b) ^ gmul(c, 0x0d) ^ gmul(d, 0x09)
|
|
state[i][1] = gmul(a, 0x09) ^ gmul(b, 0x0e) ^ gmul(c, 0x0b) ^ gmul(d, 0x0d)
|
|
state[i][2] = gmul(a, 0x0d) ^ gmul(b, 0x09) ^ gmul(c, 0x0e) ^ gmul(d, 0x0b)
|
|
state[i][3] = gmul(a, 0x0b) ^ gmul(b, 0x0d) ^ gmul(c, 0x09) ^ gmul(d, 0x0e)
|
|
return state
|
|
|
|
def inv_add_round_key(state, round_key):
|
|
for i in range(4):
|
|
for j in range(4):
|
|
state[i][j] ^= round_key[i][j]
|
|
return state
|
|
|
|
def decrypt(ciphertext, key):
|
|
# Convert ciphertext and key to matrix
|
|
ciphertext_matrix = hex_to_4x4_hex_matrix(ciphertext)
|
|
key_matrix = hex_to_4x4_hex_matrix(key)
|
|
|
|
# Key Expansion
|
|
expanded_key = key_expansion(key_matrix)
|
|
|
|
# Initial Round
|
|
state = add_round_key(ciphertext_matrix, expanded_key[40:])
|
|
|
|
# Rounds
|
|
for i in range(9):
|
|
state = inv_add_round_key(state, expanded_key[36-4*i:40-4*i])
|
|
state = inv_shift_rows(state)
|
|
state = inv_sub_bytes(state)
|
|
state = inv_mix_columns(state)
|
|
|
|
|
|
|
|
# Final Round
|
|
state = inv_add_round_key(state, key_matrix)
|
|
state = inv_shift_rows(state)
|
|
state = inv_sub_bytes(state)
|
|
|
|
|
|
# Convert state to hex string
|
|
plaintext = convert_state_to_hex_string(state)
|
|
print("\nPlaintext:", plaintext)
|
|
return plaintext
|
|
|
|
|
|
def main():
|
|
plaintext = "0123456789abcdeffedcba9876543210" # 128-bit plaintext
|
|
key = "0f1571c947d9e8590cb7add6af7f6798" # 128-bit key
|
|
|
|
print ("Plaintext:", plaintext)
|
|
print ("Key:", key)
|
|
|
|
print ("\nEncrypting with AES")
|
|
ciphertext = encrypt(plaintext, key)
|
|
|
|
print ("\nDecrypting with AES")
|
|
plaintext = decrypt(ciphertext, key)
|
|
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main()
|