aes-vial 0.1.0

A simple wrapper for AES CTR mode.

Vial is a simple wrapper for AES CTR mode. You have to set the key to

an appropriate length:

AES-128bit (16 bytes/characters)
AES-192bit (24 bytes/characters)
AES-256bit (32 bytes/characters)

or use a hashing package that’ll provide more security and ease your pain of

typing exactly the 16, 24 or 32 characters.

Usage:

import vial

vial = vial.Vial(key)
vial.encrypt(plaintext, output_counter_file)
vial.decrypt(plaintext, output_counter_file)
vial.encrypt_stream(input, output, block_size)
vial.decrypt_stream(input, output, block_size)

encrypt(text, counter_path)

This function needs as an extra argument a path where you want

the file with initial Counter value stored. The file is important,

you need to use it to decrypt.

Returns: encrypted text (bytes)

decrypt(text, counter_path)

This function needs as an extra argument the path where you saved

the file from Vial.encrypt(). Without this file the text won’t be

decrypted.

Returns: decrypted text (bytes)

encrypt_stream(input, output, block_size=4096)

This function needs as extra arguments only input file and a path

for the output file. A file with Counter’s initial value will be

created automatically in the same location and with the same name as

output file.

Args:

input, output: Expects a file object ( f = open(...) )
block_size (optional): The max block_size to encrypt with the same
                       AES encrypt()

Example:

vial = Vial(key)
input = open('encrypt_me.png', 'rb')
output = open('im_encrypted.png', 'wb')
vial.encrypt_stream(input, output)
input.close()
output.close()

Result:

root/
    encrypt_me.png
    im_encrypted.png
    im_encrypted.ctr

decrypt_stream(input, output, block_size=4096)

This function needs as extra arguments only input file and a path

for the output file. The file with Counter’s initial value has to be

placed in the same folder as the input file as the function

automatically checks for it and gets the value to decrypt it.

Args:

input, output: Expects a file object ( f = open(...) )
block_size (optional): The max block_size to decrypt with the same
                       AES decrypt()

Example:

vial = Vial(key)
input = open('im_encrypted.png', 'rb')
output = open('im_decrypted.png', 'wb')
vial.encrypt_stream(input, output)
input.close()
output.close()

Result:

root/
    im_encrypted.png
    im_encrypted.ctr
    im_decrypted.png