def keyExchangeProtocol():
p_A, g_A = DiffieHellman.p, DiffieHellman.g
keyPairA = DiffieHellman.generateKeyPair(p_A, g_A)
A = keyPairA[1]
print("A to B: p, g, A")
keyPairB = DiffieHellman.generateKeyPair(p_A, g_A)
B = keyPairB[1]
print("B to A: B")
secretKeyA = DiffieHellman.DH(B, keyPairA, p_A)
secretKeyB = DiffieHellman.DH(A, keyPairB, p_A)
messageA = 'This is my message suckerr.\nYour\'s Sincerely\nA'
messageA = bytes(messageA.encode('latin1'))
secretKeyA_bytes = bytes.fromhex(hex(secretKeyA)[2:])
AESkeyA = hashlib.sha1(secretKeyA_bytes).digest()[:16]
IV_A = helpers.getRandBytes(16)
ct = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(messageA, 16), AESkeyA, IV_A)
secretKeyB_bytes = bytes.fromhex(hex(secretKeyB)[2:])
AESkeyB = hashlib.sha1(secretKeyB_bytes).digest()[:16]
pt = AES_CBC.AES_CBCdecrypt(ct, AESkeyB, IV_A)
if PKCS7.PKCS7validate(pt, 16):
pt = PKCS7.PKCS7unpad(pt)
else:
raise Exception('Something is wrong')
IV_B = helpers.getRandBytes(16)
ct_BtoA = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(pt, 16), AESkeyB, IV_B)
messageA2 = AES_CBC.AES_CBCdecrypt(ct_BtoA, AESkeyA, IV_B)
if PKCS7.PKCS7validate(messageA2, 16):
messageA2 = PKCS7.PKCS7unpad(messageA2)
else:
raise Exception('Something is wrong')
if messageA == messageA2:
print('Connection established')
else:
print('No connection')
def encrypt(ipBytes):
global GLOBAL_KEY
global GLOBAL_IV
if GLOBAL_KEY == None:
GLOBAL_KEY = helpers.getRandBytes(16)
if GLOBAL_IV == None:
GLOBAL_IV = GLOBAL_KEY
ct = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(ipBytes, 16), GLOBAL_KEY,
GLOBAL_IV)
return ct
def encrypt(userInputString):
global GLOBAL_KEY
global IV
if GLOBAL_KEY == None:
GLOBAL_KEY = getRandBytes(16)
if IV == None:
IV = getRandBytes(16)
userInputString = quoteMetachars(userInputString)
stringToPrepend = "comment1=cooking%20MCs;userdata="
stringToAppend = ";comment2=%20like%20a%20pound%20of%20bacon"
finalString = stringToPrepend + userInputString + stringToAppend
ipBytes = bytes(finalString.encode('utf-8'))
ct = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(ipBytes, 16), GLOBAL_KEY, IV)
return ct
def encryptRandString():
global GLOBAL_KEY
if GLOBAL_KEY == None:
GLOBAL_KEY = helper.getRandBytes(16)
IV = helper.getRandBytes(16)
ipFile = open("input.txt", 'r')
choice = random.randrange(1, 11)
randString = ''
for i in range(choice):
randString = ipFile.readline()
randString = randString[:len(randString) - 1]
randString = base64.b64decode(randString)
ptInput = PKCS7.PKCS7(randString, 16)
ct = AES_CBC.AES_CBCencrypt(ptInput, GLOBAL_KEY, IV)
return IV, ct
def blackBox(ptByteArray):
padBefore = random.randrange(5, 11)
padAfter = random.randrange(5, 11)
randPaddedPt = randPadPlaintext(ptByteArray, padBefore, padAfter)
key = getRandBytes(16)
encMode = random.randrange(0, 2)
if encMode == 0:
ptInput = PKCS7.PKCS7(randPaddedPt, 16)
ct = AES_ECB.AESencrypt(ptInput, key)
#print('Original: ECB')
return ct
else:
ptInput = PKCS7.PKCS7(randPaddedPt, 16)
IV = getRandBytes(16)
ct = AES_CBC.AES_CBCencrypt(ptInput, key, IV)
#print('Original: CBC')
return ct
def MITM():
p_A, g_A = DiffieHellman.p, DiffieHellman.g
keyPairA = DiffieHellman.generateKeyPair(p_A, g_A)
A = keyPairA[1]
print("A to B: p, g, A")
print("Intercepted by M")
keyPairB = DiffieHellman.generateKeyPair(p_A, g_A)
B = keyPairB[1]
print("M to B: p, g, p")
print("B to M: B")
print("M to A: p")
secretKeyA = DiffieHellman.DH(p_A, keyPairA, p_A)
secretKeyB = DiffieHellman.DH(p_A, keyPairB, p_A)
messageA = 'This is my message suckerr.\nYour\'s Sincerely\nA'
messageA = bytes(messageA.encode('latin1'))
secretKeyA_bytes = bytes.fromhex(
hex(secretKeyA)[2:] if len(hex(secretKeyA)[2:]) % 2 == 0 else '0' +
hex(secretKeyA)[2:])
AESkeyA = hashlib.sha1(secretKeyA_bytes).digest()[:16]
IV_A = helpers.getRandBytes(16)
ct = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(messageA, 16), AESkeyA, IV_A)
secretKeyB_bytes = bytes.fromhex(
hex(secretKeyB)[2:] if len(hex(secretKeyB)[2:]) % 2 == 0 else '0' +
hex(secretKeyB)[2:])
AESkeyB = hashlib.sha1(secretKeyB_bytes).digest()[:16]
pt = AES_CBC.AES_CBCdecrypt(ct, AESkeyB, IV_A)
if PKCS7.PKCS7validate(pt, 16):
pt = PKCS7.PKCS7unpad(pt)
else:
raise Exception('Something is wrong')
IV_B = helpers.getRandBytes(16)
ct_BtoA = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(pt, 16), AESkeyB, IV_B)
messageA2 = AES_CBC.AES_CBCdecrypt(ct_BtoA, AESkeyA, IV_B)
if PKCS7.PKCS7validate(messageA2, 16):
messageA2 = PKCS7.PKCS7unpad(messageA2)
else:
raise Exception('Something is wrong')
if messageA == messageA2:
print('Connection established')
else:
print('No connection')
AESkeyM = hashlib.sha1(bytes.fromhex('00')).digest()[:16]
messageA = 'Message 1'
messageA = bytes(messageA.encode('latin1'))
IV_A = helpers.getRandBytes(16)
ct = AES_CBC.AES_CBCencrypt(PKCS7.PKCS7(messageA, 16), AESkeyA, IV_A)
print('A:', messageA)
messageM = AES_CBC.AES_CBCdecrypt(ct, AESkeyM, IV_A)
if PKCS7.PKCS7validate(messageM, 16):
messageM = PKCS7.PKCS7unpad(messageM)
print('M:', messageM)
else:
raise Exception('Something is wrong')
messageB = AES_CBC.AES_CBCdecrypt(ct, AESkeyB, IV_A)
if PKCS7.PKCS7validate(messageB, 16):
messageB = PKCS7.PKCS7unpad(messageB)
print('B:', messageB)
else:
raise Exception('Something is wrong')