helpers.py 文件源码

def encrypt(plaintext, key=config.SECRET, key_salt='', no_iv=False):
    """Encrypt shit the right way"""

    # sanitize inputs
    key = SHA256.new(key + key_salt).digest()
    if len(key) not in AES.key_size:
        raise Exception()
    if isinstance(plaintext, unicode):
        plaintext = plaintext.encode('utf-8')

    # pad plaintext using PKCS7 padding scheme
    padlen = AES.block_size - len(plaintext) % AES.block_size
    plaintext += chr(padlen) * padlen

    # generate random initialization vector using CSPRNG
    iv = '\0' * AES.block_size if no_iv else get_random_bytes(AES.block_size)

    # encrypt using AES in CFB mode
    ciphertext = AES.new(key, AES.MODE_CFB, iv).encrypt(plaintext)

    # prepend iv to ciphertext
    if not no_iv:
        ciphertext = iv + ciphertext

    # return ciphertext in hex encoding
    return ciphertext.encode('hex')