def concatAndEncrypt(plaintext):
prepend = b"comment1=cooking%20MCs;userdata="
append = b";comment2=%20like%20a%20pound%20of%20bacon"
plaintext = cleanPlaintext(plaintext)
longPlaintext = prepend + plaintext + append
nextMult = next16Multiple(len(longPlaintext))
fullPlaintext = PKCS7pad(longPlaintext, nextMult)
ciphertext = CBCencrypt(fullPlaintext, KEY, IV)
return ciphertext
def ECBOracle(yourString):
#yourString should be a BYTEstring
unknownString = "Um9sbGluJyBpbiBteSA1LjAKV2l0aCBteSByYWctdG9wIGRvd24gc28gbXkgaGFpciBjYW4gYmxvdwpUaGUgZ2lybGllcyBvbiBzdGFuZGJ5IHdhdmluZyBqdXN0IHRvIHNheSBoaQpEaWQgeW91IHN0b3A/IE5vLCBJIGp1c3QgZHJvdmUgYnkK"
decodedString = base64.b64decode(unknownString)
totalString = yourString + decodedString
targetLen = next16Multiple(len(totalString))
paddedPlaintext = PKCS7pad(totalString, targetLen)
ciphertext = AESencrypt(paddedPlaintext, KEY)
return ciphertext
def getListOfBlocks(plaintext):
#assuming we want 128 bit blocks -- 16 byte blocks
result = []
for i in range(len(plaintext)):
if i % 16 == 0:
result.append(bytes([plaintext[i]]))
else:
result[-1] += bytes([plaintext[i]])
if len(result[-1]) != 16:
result[-1] = PKCS7pad(result[-1], 16)
return result
def encryptionOracle(plaintext):
key = random16Bytes()
padLens = randrange(5, 11)
plaintext = padPlaintext(plaintext, padLens, padLens)
ECBorCBC = randrange(0, 2)
if ECBorCBC == 1:
print("using ECB")
length = next16Multiple(len(plaintext))
plaintext = PKCS7pad(plaintext, length)
ciphertext = AESencrypt(plaintext, key)
else:
print("using CBC")
IV = random16Bytes()
ciphertext = CBCencrypt(plaintext, key, IV)
return ciphertext
def encryptAString():
possibilities = [b"MDAwMDAwTm93IHRoYXQgdGhlIHBhcnR5IGlzIGp1bXBpbmc=",
b"MDAwMDAxV2l0aCB0aGUgYmFzcyBraWNrZWQgaW4gYW5kIHRoZSBWZWdhJ3MgYXJlIHB1bXBpbic=",
b"MDAwMDAyUXVpY2sgdG8gdGhlIHBvaW50LCB0byB0aGUgcG9pbnQsIG5vIGZha2luZw==",
b"MDAwMDAzQ29va2luZyBNQydzIGxpa2UgYSBwb3VuZCBvZiBiYWNvbg==",
b"MDAwMDA0QnVybmluZyAnZW0sIGlmIHlvdSBhaW4ndCBxdWljayBhbmQgbmltYmxl",
b"MDAwMDA1SSBnbyBjcmF6eSB3aGVuIEkgaGVhciBhIGN5bWJhbA==",
b"MDAwMDA2QW5kIGEgaGlnaCBoYXQgd2l0aCBhIHNvdXBlZCB1cCB0ZW1wbw==",
b"MDAwMDA3SSdtIG9uIGEgcm9sbCwgaXQncyB0aW1lIHRvIGdvIHNvbG8=",
b"MDAwMDA4b2xsaW4nIGluIG15IGZpdmUgcG9pbnQgb2g=",
b"MDAwMDA5aXRoIG15IHJhZy10b3AgZG93biBzbyBteSBoYWlyIGNhbiBibG93"]
#index = randrange(0, len(possibilities))
#MAKE IT RANDOM HERE TOO
index = 2
mult = next16Multiple(len(possibilities[index]))
padded = PKCS7pad(possibilities[index], mult)
ciphertext = CBCencrypt(padded, KEY, IV)
return ciphertext
def decryptUserProfile(ciphertext):
ciphertext = ciphertext #################
targetLen = next16Multiple(len(ciphertext))
paddedCiphertext = PKCS7pad(ciphertext, targetLen)
plaintext = AESdecrypt(paddedCiphertext, KEY)
return plaintext
def encryptUserProfile(string):
byteString = string ###################
targetLen = next16Multiple(len(byteString))
paddedPlaintext = PKCS7pad(byteString, targetLen)
ciphertext = AESencrypt(paddedPlaintext, KEY)
return ciphertext