encryption.py 文件源码

def decrypt(self, signature, encrypted_msg, host):
        '''
        Decrypt received message. If this message can't be verified then
        return None.

        Args:
            encrypted_msg (bytes) Encrypted message from a user in the chat
        Return:
            None if message isn't verified else decrypted message
        '''

        user_id = self._client.host2user_id[host]
        decrypted_msg = self._keypair.decrypt(encrypted_msg)
        decrypted_msg_hash = SHA256.new(decrypted_msg).digest()

        if self.verify(decrypted_msg_hash, signature, user_id):
            return decrypted_msg.decode('utf-8')