# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.
from __future__ import absolute_import, division, print_function
import abc
import six
from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
[docs]@six.add_metaclass(abc.ABCMeta)
class X25519PublicKey(object):
[docs] @classmethod
def from_public_bytes(cls, data):
from cryptography.hazmat.backends.openssl.backend import backend
if not backend.x25519_supported():
raise UnsupportedAlgorithm(
"X25519 is not supported by this version of OpenSSL.",
_Reasons.UNSUPPORTED_EXCHANGE_ALGORITHM,
)
return backend.x25519_load_public_bytes(data)
[docs] @abc.abstractmethod
def public_bytes(self, encoding, format):
"""
The serialized bytes of the public key.
"""
[docs]@six.add_metaclass(abc.ABCMeta)
class X25519PrivateKey(object):
[docs] @classmethod
def generate(cls):
from cryptography.hazmat.backends.openssl.backend import backend
if not backend.x25519_supported():
raise UnsupportedAlgorithm(
"X25519 is not supported by this version of OpenSSL.",
_Reasons.UNSUPPORTED_EXCHANGE_ALGORITHM,
)
return backend.x25519_generate_key()
[docs] @classmethod
def from_private_bytes(cls, data):
from cryptography.hazmat.backends.openssl.backend import backend
if not backend.x25519_supported():
raise UnsupportedAlgorithm(
"X25519 is not supported by this version of OpenSSL.",
_Reasons.UNSUPPORTED_EXCHANGE_ALGORITHM,
)
return backend.x25519_load_private_bytes(data)
[docs] @abc.abstractmethod
def public_key(self):
"""
The serialized bytes of the public key.
"""
[docs] @abc.abstractmethod
def private_bytes(self, encoding, format, encryption_algorithm):
"""
The serialized bytes of the private key.
"""
[docs] @abc.abstractmethod
def exchange(self, peer_public_key):
"""
Performs a key exchange operation using the provided peer's public key.
"""