type ChaCha

Pure python implementation of ChaCha cipher

Instance Methods

__init__(self, key, nonce, counter=0, rounds=20)
Set the initial state for the ChaCha cipher

source code

decrypt(self, ciphertext)
Decrypt the data

source code

encrypt(self, plaintext)
Encrypt the data

source code

Class Methods

double_round(cls, x)
Perform two rounds of ChaCha cipher

source code

Static Methods

_bytearray_to_words(data)
Convert a bytearray to array of word sized ints

source code

chacha_block(key, counter, nonce, rounds)
Generate a state of a single block

source code

quarter_round(x, a, b, c, d)
Perform a ChaCha quarter round

source code

rotl32(v, c)
Rotate left a 32 bit integer v by c bits

source code

word_to_bytearray(state)
Convert state to little endian bytestream

source code

Class Variables

_round_mixup_box = [(0, 4, 8, 12), (1, 5, 9, 13), (2, 6, 10, 1...

constants = [1634760805, 857760878, 2036477234, 1797285236]

Method Details

Set the initial state for the ChaCha cipher

Class Variable Details

Value:

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