eric: comparison Utilities/crypto/py3AES.py

-:c6f16f1b9958
+:7f0ef975da9e
 # from the SlowAES project, http://code.google.com/p/slowaes/
 #
 # Copyright (c) 2008    Josh Davis ( http://www.josh-davis.org ),
 #           Alex Martelli ( http://www.aleax.it )
 #
-# Ported from C code written by Laurent Haan ( http://www.progressive-coding.com )
+# Ported from C code written by Laurent Haan
+# ( http://www.progressive-coding.com )
 #
 # Licensed under the Apache License, Version 2.0
 # http://www.apache.org/licenses/
 #
 @param b data to be stripped (bytes)
 @return stripped data (bytes)
 """
 if len(b) % 16 or not b:
-raise ValueError("Data of len {0} can't be PCKS7-padded".format(len(b)))
+raise ValueError(
+"Data of len {0} can't be PCKS7-padded".format(len(b)))
 numpads = b[-1]
 if numpads > 16:
-raise ValueError("Data ending with {0} can't be PCKS7-padded".format(b[-1]))
+raise ValueError(
+"Data ending with {0} can't be PCKS7-padded".format(b[-1]))
 return b[:-numpads]
 class AES(object):
 """
 def __rotate(self, data):
 """
 Private method performing Rijndael's key schedule rotate operation.
-Rotate the data word eight bits to the left: eg, rotate(1d2c3a4f) == 2c3a4f1d.
+Rotate the data word eight bits to the left: eg,
+rotate(1d2c3a4f) == 2c3a4f1d.
 @param data data of size 4 (bytearray)
 """
 return data[1:] + data[:1]
 # and increment rconIteration afterwards
 if currentSize % size == 0:
 t = self.__core(t, rconIteration)
 rconIteration += 1
 # For 256-bit keys, we add an extra sbox to the calculation
-if size == self.KeySize["SIZE_256"] and ((currentSize % size) == 16):
+if size == self.KeySize["SIZE_256"] and \
+((currentSize % size) == 16):
 for l in range(4):
 t[l] = self.__getSBoxValue(t[l])
 # We XOR t with the four-byte block 16, 24, 32 bytes before the new
-# expanded key. This becomes the next four bytes in the expanded key.
+# expanded key. This becomes the next four bytes in the expanded
+# key.
 for m in range(4):
 expandedKey[currentSize] = \
 expandedKey[currentSize - size] ^ t[m]
 currentSize += 1
 roundKey[j * 4 + i] = expandedKey[roundKeyPointer + i * 4 + j]
 return roundKey
 def __galois_multiplication(self, a, b):
 """
-Private method to perform a Galois multiplication of 8 bit characters a and b.
+Private method to perform a Galois multiplication of 8 bit characters
+a and b.
 @param a first factor (byte)
 @param b second factor (byte)
 @return result (byte)
 """
 b >>= 1
 return p
 def __subBytes(self, state, isInv):
 """
-Private method to substitute all the values from the state with the value in
+Private method to substitute all the values from the state with the
-the SBox using the state value as index for the SBox.
+value in the SBox using the state value as index for the SBox.
 @param state state to be worked on (bytearray)
 @param isInv flag indicating an inverse operation (boolean)
 @return modified state (bytearray)
 """
 return state
 # galois multiplication of 1 column of the 4x4 matrix
 def __mixColumn(self, column, isInv):
 """
-Private method to perform a galois multiplication of 1 column the 4x4 matrix.
+Private method to perform a galois multiplication of 1 column the
+4x4 matrix.
 @param column column to be worked on (bytearray)
 @param isInv flag indicating an inverse operation (boolean)
 @return modified column (bytearray)
 """
 g(cpy[1], mult[2]) ^ g(cpy[0], mult[3])
 return column
 def __aes_round(self, state, roundKey):
 """
-Private method to apply the 4 operations of the forward round in sequence.
+Private method to apply the 4 operations of the forward round in
+sequence.
 @param state state to be worked on (bytearray)
 @param roundKey round key to be used (bytearray)
 @return modified state (bytearray)
 """
 state = self.__addRoundKey(state, roundKey)
 return state
 def __aes_invRound(self, state, roundKey):
 """
-Private method to apply the 4 operations of the inverse round in sequence.
+Private method to apply the 4 operations of the inverse round in
+sequence.
 @param state state to be worked on (bytearray)
 @param roundKey round key to be used (bytearray)
 @return modified state (bytearray)
 """
 state = self.__mixColumns(state, True)
 return state
 def __aes_main(self, state, expandedKey, nbrRounds):
 """
-Private method to perform the initial operations, the standard round, and the
+Private method to do the AES encryption for one round.
-final operations of the forward AES, creating a round key for each round.
+Perform the initial operations, the standard round, and the
+final operations of the forward AES, creating a round key for
+each round.
 @param state state to be worked on (bytearray)
 @param expandedKey expanded key to be used (bytearray)
 @param nbrRounds number of rounds to be done (integer)
 @return modified state (bytearray)
 """
-state = self.__addRoundKey(state, self.__createRoundKey(expandedKey, 0))
+state = self.__addRoundKey(
+state, self.__createRoundKey(expandedKey, 0))
 i = 1
 while i < nbrRounds:
 state = self.__aes_round(
 state, self.__createRoundKey(expandedKey, 16 * i))
 i += 1
 state, self.__createRoundKey(expandedKey, 16 * nbrRounds))
 return state
 def __aes_invMain(self, state, expandedKey, nbrRounds):
 """
-Private method to perform the initial operations, the standard round, and the
+Private method to do the inverse AES encryption for one round.
-final operations of the inverse AES, creating a round key for each round.
+Perform the initial operations, the standard round, and the
+final operations of the inverse AES, creating a round key for
+each round.
 @param state state to be worked on (bytearray)
 @param expandedKey expanded key to be used (bytearray)
 @param nbrRounds number of rounds to be done (integer)
 @return modified state (bytearray)
 state = self.__aes_invRound(
 state, self.__createRoundKey(expandedKey, 16 * i))
 i -= 1
 state = self.__shiftRows(state, True)
 state = self.__subBytes(state, True)
-state = self.__addRoundKey(state, self.__createRoundKey(expandedKey, 0))
+state = self.__addRoundKey(
+state, self.__createRoundKey(expandedKey, 0))
 return state
 def encrypt(self, iput, key, size):
 """
-Public method to encrypt a 128 bit input block against the given key of size
+Public method to encrypt a 128 bit input block against the given key
-specified.
+of size specified.
 @param iput input data (bytearray)
 @param key key to be used (bytes or bytearray)
 @param size key size (16, 24 or 32)
 @return encrypted data (bytes)
 return bytes(output)
 # decrypts a 128 bit input block against the given key of size specified
 def decrypt(self, iput, key, size):
 """
-Public method to decrypt a 128 bit input block against the given key of size
+Public method to decrypt a 128 bit input block against the given key
-specified.
+of size specified.
 @param iput input data (bytearray)
 @param key key to be used (bytes or bytearray)
 @param size key size (16, 24 or 32)
 @return decrypted data (bytes)
 """
 key = bytearray(key)
 if mode == AESModeOfOperation.ModeOfOperation["CBC"]:
 data = append_PKCS7_padding(data)
 keysize = len(key)
-assert keysize in AES.KeySize.values(), 'invalid key size: {0}'.format(keysize)
+assert keysize in AES.KeySize.values(), \
+'invalid key size: {0}'.format(keysize)
 # create a new iv using random data
 iv = bytearray([i for i in os.urandom(16)])
 moo = AESModeOfOperation()
 mode, length, ciph = moo.encrypt(data, mode, key, keysize, iv)
 # With padding, the original length does not need to be known. It's a bad
 def decryptData(key, data, mode=AESModeOfOperation.ModeOfOperation["CBC"]):
 """
 Module function to decrypt the given data with the given key.
 @param key key to be used for decryption (bytes)
-@param data data to be decrypted (with initialization vector prepended) (bytes)
+@param data data to be decrypted (with initialization vector prepended)
+(bytes)
 @param mode mode of operations (0, 1 or 2)
 @return decrypted data (bytes)
 @exception ValueError key size is invalid or decrypted data is invalid
 """
 key = bytearray(key)

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comparison: Utilities/crypto/py3AES.py

Utilities/crypto/py3AES.py