def __init__(self, private_k_path):
'''
Initiate encryptor with the private key and public key
:param private_k_path:
:return:
'''
self.private_key = PrivateKeyUtil(private_k_path) if private_k_path is not None else None
class Decryptor():
sender_pub_key = None
private_key = None
def __init__(self, private_k_path):
'''
Initiate encryptor with the private key and public key
:param private_k_path:
:return:
'''
self.private_key = PrivateKeyUtil(private_k_path) if private_k_path is not None else None
def rsa_decrypt(self, c_text):
if len(c_text) > c.C_TEXT_LEN_4096:
c_text_1 = c_text[:c.C_TEXT_LEN_4096]
c_text_2 = c_text[c.C_TEXT_LEN_4096:]
p_text_1 = self.private_key.decrypt(c_text_1)
p_text_2 = self.private_key.decrypt(c_text_2)
p_text = p_text_1 + p_text_2
else:
p_text = self.private_key.decrypt(c_text)
return p_text
def sym_decrypt(self, secret, c_file):
# separate the header and content from c_text
c_header = c_file[:c.HEADER_LENGTH]
c_text = c_file[c.HEADER_LENGTH:]
# parse header to get digest
iv = c_header
# decrypt the cipher text
cipher = Cipher(algorithms.AES(secret), modes.CBC(iv), backend=default_backend())
decryptor = cipher.decryptor()
p_text = decryptor.update(c_text) + decryptor.finalize()
# unpadding
unpadder = padding.PKCS7(128).unpadder()
unpadded_data = unpadder.update(p_text)
unpadded_data += unpadder.finalize()
return unpadded_data
def parse_header(self, header):
# TODO exception handling
iv = header
return iv
def rsa_sign(self, msg):
sign = self.private_key.sign(msg)
return sign
