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943 lines
28 KiB
943 lines
28 KiB
.. hazmat::
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Elliptic curve cryptography
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===========================
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.. module:: cryptography.hazmat.primitives.asymmetric.ec
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.. function:: generate_private_key(curve, backend)
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.. versionadded:: 0.5
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Generate a new private key on ``curve`` for use with ``backend``.
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:param curve: An instance of :class:`EllipticCurve`.
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:param backend: An instance of
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:class:`~cryptography.hazmat.backends.interfaces.EllipticCurveBackend`.
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:returns: A new instance of :class:`EllipticCurvePrivateKey`.
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.. function:: derive_private_key(private_value, curve, backend)
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.. versionadded:: 1.6
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Derive a private key from ``private_value`` on ``curve`` for use with
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``backend``.
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:param int private_value: The secret scalar value.
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:param curve: An instance of :class:`EllipticCurve`.
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:param backend: An instance of
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:class:`~cryptography.hazmat.backends.interfaces.EllipticCurveBackend`.
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:returns: A new instance of :class:`EllipticCurvePrivateKey`.
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Elliptic Curve Signature Algorithms
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-----------------------------------
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.. class:: ECDSA(algorithm)
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.. versionadded:: 0.5
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The ECDSA signature algorithm first standardized in NIST publication
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`FIPS 186-3`_, and later in `FIPS 186-4`_.
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:param algorithm: An instance of
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:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`.
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.. doctest::
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>>> from cryptography.hazmat.backends import default_backend
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>>> from cryptography.hazmat.primitives import hashes
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>>> from cryptography.hazmat.primitives.asymmetric import ec
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>>> private_key = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... )
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>>> data = b"this is some data I'd like to sign"
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>>> signature = private_key.sign(
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... data,
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... ec.ECDSA(hashes.SHA256())
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... )
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The ``signature`` is a ``bytes`` object, whose contents is DER encoded as
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described in :rfc:`3279`. This can be decoded using
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:func:`~cryptography.hazmat.primitives.asymmetric.utils.decode_dss_signature`.
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If your data is too large to be passed in a single call, you can hash it
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separately and pass that value using
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:class:`~cryptography.hazmat.primitives.asymmetric.utils.Prehashed`.
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.. doctest::
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>>> from cryptography.hazmat.primitives.asymmetric import utils
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>>> chosen_hash = hashes.SHA256()
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>>> hasher = hashes.Hash(chosen_hash, default_backend())
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>>> hasher.update(b"data & ")
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>>> hasher.update(b"more data")
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>>> digest = hasher.finalize()
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>>> sig = private_key.sign(
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... digest,
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... ec.ECDSA(utils.Prehashed(chosen_hash))
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... )
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Verification requires the public key, the signature itself, the signed
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data, and knowledge of the hashing algorithm that was used when producing
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the signature:
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>>> public_key = private_key.public_key()
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>>> public_key.verify(signature, data, ec.ECDSA(hashes.SHA256()))
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If the signature is not valid, an
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:class:`~cryptography.exceptions.InvalidSignature` exception will be raised.
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If your data is too large to be passed in a single call, you can hash it
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separately and pass that value using
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:class:`~cryptography.hazmat.primitives.asymmetric.utils.Prehashed`.
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.. doctest::
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>>> chosen_hash = hashes.SHA256()
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>>> hasher = hashes.Hash(chosen_hash, default_backend())
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>>> hasher.update(b"data & ")
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>>> hasher.update(b"more data")
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>>> digest = hasher.finalize()
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>>> public_key.verify(
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... sig,
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... digest,
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... ec.ECDSA(utils.Prehashed(chosen_hash))
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... )
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.. note::
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Although in this case the public key was derived from the private one,
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in a typical setting you will not possess the private key. The
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`Key loading`_ section explains how to load the public key from other
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sources.
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.. class:: EllipticCurvePrivateNumbers(private_value, public_numbers)
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.. versionadded:: 0.5
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The collection of integers that make up an EC private key.
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.. attribute:: public_numbers
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:type: :class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicNumbers`
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The :class:`EllipticCurvePublicNumbers` which makes up the EC public
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key associated with this EC private key.
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.. attribute:: private_value
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:type: int
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The private value.
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.. method:: private_key(backend)
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Convert a collection of numbers into a private key suitable for doing
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actual cryptographic operations.
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:param backend: An instance of
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:class:`~cryptography.hazmat.backends.interfaces.EllipticCurveBackend`.
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:returns: A new instance of :class:`EllipticCurvePrivateKey`.
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.. class:: EllipticCurvePublicNumbers(x, y, curve)
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.. warning::
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The point represented by this object is not validated in any way until
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:meth:`EllipticCurvePublicNumbers.public_key` is called and may not
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represent a valid point on the curve. You should not attempt to perform
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any computations using the values from this class until you have either
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validated it yourself or called ``public_key()`` successfully.
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.. versionadded:: 0.5
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The collection of integers that make up an EC public key.
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.. attribute:: curve
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:type: :class:`EllipticCurve`
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The elliptic curve for this key.
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.. attribute:: x
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:type: int
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The affine x component of the public point used for verifying.
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.. attribute:: y
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:type: int
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The affine y component of the public point used for verifying.
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.. method:: public_key(backend)
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Convert a collection of numbers into a public key suitable for doing
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actual cryptographic operations.
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:param backend: An instance of
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:class:`~cryptography.hazmat.backends.interfaces.EllipticCurveBackend`.
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:raises ValueError: Raised if the point is invalid for the curve.
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:returns: A new instance of :class:`EllipticCurvePublicKey`.
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.. method:: encode_point()
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.. warning::
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This method is deprecated as of version 2.5. Callers should migrate
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to using
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:meth:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicKey.public_bytes`.
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.. versionadded:: 1.1
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Encodes an elliptic curve point to a byte string as described in
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`SEC 1 v2.0`_ section 2.3.3. This method only supports uncompressed
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points.
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:return bytes: The encoded point.
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.. classmethod:: from_encoded_point(curve, data)
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.. versionadded:: 1.1
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.. note::
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This has been deprecated in favor of
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:meth:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicKey.from_encoded_point`
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Decodes a byte string as described in `SEC 1 v2.0`_ section 2.3.3 and
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returns an :class:`EllipticCurvePublicNumbers`. This method only
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supports uncompressed points.
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:param curve: An
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:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurve`
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instance.
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:param bytes data: The serialized point byte string.
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:returns: An :class:`EllipticCurvePublicNumbers` instance.
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:raises ValueError: Raised on invalid point type or data length.
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:raises TypeError: Raised when curve is not an
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:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurve`.
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Elliptic Curve Key Exchange algorithm
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-------------------------------------
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.. class:: ECDH()
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.. versionadded:: 1.1
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The Elliptic Curve Diffie-Hellman Key Exchange algorithm first standardized
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in NIST publication `800-56A`_, and later in `800-56Ar2`_.
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For most applications the ``shared_key`` should be passed to a key
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derivation function. This allows mixing of additional information into the
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key, derivation of multiple keys, and destroys any structure that may be
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present.
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.. warning::
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This example does not give `forward secrecy`_ and is only provided as a
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demonstration of the basic Diffie-Hellman construction. For real world
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applications always use the ephemeral form described after this example.
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.. doctest::
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>>> from cryptography.hazmat.backends import default_backend
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>>> from cryptography.hazmat.primitives import hashes
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>>> from cryptography.hazmat.primitives.asymmetric import ec
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>>> from cryptography.hazmat.primitives.kdf.hkdf import HKDF
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>>> # Generate a private key for use in the exchange.
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>>> server_private_key = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... )
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>>> # In a real handshake the peer is a remote client. For this
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>>> # example we'll generate another local private key though.
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>>> peer_private_key = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... )
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>>> shared_key = server_private_key.exchange(
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... ec.ECDH(), peer_private_key.public_key())
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>>> # Perform key derivation.
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>>> derived_key = HKDF(
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... algorithm=hashes.SHA256(),
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... length=32,
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... salt=None,
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... info=b'handshake data',
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... backend=default_backend()
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... ).derive(shared_key)
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>>> # And now we can demonstrate that the handshake performed in the
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>>> # opposite direction gives the same final value
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>>> same_shared_key = peer_private_key.exchange(
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... ec.ECDH(), server_private_key.public_key())
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>>> # Perform key derivation.
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>>> same_derived_key = HKDF(
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... algorithm=hashes.SHA256(),
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... length=32,
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... salt=None,
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... info=b'handshake data',
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... backend=default_backend()
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... ).derive(same_shared_key)
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>>> derived_key == same_derived_key
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True
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ECDHE (or EECDH), the ephemeral form of this exchange, is **strongly
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preferred** over simple ECDH and provides `forward secrecy`_ when used.
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You must generate a new private key using :func:`generate_private_key` for
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each :meth:`~EllipticCurvePrivateKey.exchange` when performing an ECDHE key
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exchange. An example of the ephemeral form:
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.. doctest::
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>>> from cryptography.hazmat.backends import default_backend
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>>> from cryptography.hazmat.primitives import hashes
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>>> from cryptography.hazmat.primitives.asymmetric import ec
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>>> from cryptography.hazmat.primitives.kdf.hkdf import HKDF
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>>> # Generate a private key for use in the exchange.
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>>> private_key = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... )
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>>> # In a real handshake the peer_public_key will be received from the
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>>> # other party. For this example we'll generate another private key
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>>> # and get a public key from that.
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>>> peer_public_key = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... ).public_key()
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>>> shared_key = private_key.exchange(ec.ECDH(), peer_public_key)
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>>> # Perform key derivation.
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>>> derived_key = HKDF(
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... algorithm=hashes.SHA256(),
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... length=32,
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... salt=None,
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... info=b'handshake data',
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... backend=default_backend()
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... ).derive(shared_key)
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>>> # For the next handshake we MUST generate another private key.
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>>> private_key_2 = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... )
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>>> peer_public_key_2 = ec.generate_private_key(
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... ec.SECP384R1(), default_backend()
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... ).public_key()
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>>> shared_key_2 = private_key_2.exchange(ec.ECDH(), peer_public_key_2)
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>>> derived_key_2 = HKDF(
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... algorithm=hashes.SHA256(),
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... length=32,
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... salt=None,
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... info=b'handshake data',
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... backend=default_backend()
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... ).derive(shared_key_2)
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Elliptic Curves
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---------------
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Elliptic curves provide equivalent security at much smaller key sizes than
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other asymmetric cryptography systems such as RSA or DSA. For many operations
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elliptic curves are also significantly faster; `elliptic curve diffie-hellman
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is faster than diffie-hellman`_.
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.. note::
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Curves with a size of `less than 224 bits`_ should not be used. You should
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strongly consider using curves of at least 224 :term:`bits`.
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Generally the NIST prime field ("P") curves are significantly faster than the
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other types suggested by NIST at both signing and verifying with ECDSA.
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Prime fields also `minimize the number of security concerns for elliptic-curve
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cryptography`_. However, there is `some concern`_ that both the prime field and
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binary field ("B") NIST curves may have been weakened during their generation.
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Currently `cryptography` only supports NIST curves, none of which are
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considered "safe" by the `SafeCurves`_ project run by Daniel J. Bernstein and
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Tanja Lange.
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All named curves are instances of :class:`EllipticCurve`.
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.. class:: SECP256R1
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.. versionadded:: 0.5
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SECG curve ``secp256r1``. Also called NIST P-256.
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.. class:: SECP384R1
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.. versionadded:: 0.5
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SECG curve ``secp384r1``. Also called NIST P-384.
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.. class:: SECP521R1
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.. versionadded:: 0.5
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SECG curve ``secp521r1``. Also called NIST P-521.
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.. class:: SECP224R1
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.. versionadded:: 0.5
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SECG curve ``secp224r1``. Also called NIST P-224.
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.. class:: SECP192R1
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.. versionadded:: 0.5
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SECG curve ``secp192r1``. Also called NIST P-192.
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.. class:: SECP256K1
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.. versionadded:: 0.9
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SECG curve ``secp256k1``.
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.. class:: BrainpoolP256R1
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.. versionadded:: 2.2
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Brainpool curve specified in :rfc:`5639`. These curves are discouraged
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for new systems.
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.. class:: BrainpoolP384R1
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.. versionadded:: 2.2
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Brainpool curve specified in :rfc:`5639`. These curves are discouraged
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for new systems.
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.. class:: BrainpoolP512R1
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.. versionadded:: 2.2
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Brainpool curve specified in :rfc:`5639`. These curves are discouraged
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for new systems.
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.. class:: SECT571K1
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.. versionadded:: 0.5
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SECG curve ``sect571k1``. Also called NIST K-571. These binary curves are
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discouraged for new systems.
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.. class:: SECT409K1
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.. versionadded:: 0.5
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SECG curve ``sect409k1``. Also called NIST K-409. These binary curves are
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discouraged for new systems.
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.. class:: SECT283K1
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.. versionadded:: 0.5
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SECG curve ``sect283k1``. Also called NIST K-283. These binary curves are
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discouraged for new systems.
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.. class:: SECT233K1
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.. versionadded:: 0.5
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SECG curve ``sect233k1``. Also called NIST K-233. These binary curves are
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discouraged for new systems.
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.. class:: SECT163K1
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.. versionadded:: 0.5
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SECG curve ``sect163k1``. Also called NIST K-163. These binary curves are
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discouraged for new systems.
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.. class:: SECT571R1
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.. versionadded:: 0.5
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SECG curve ``sect571r1``. Also called NIST B-571. These binary curves are
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discouraged for new systems.
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.. class:: SECT409R1
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.. versionadded:: 0.5
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SECG curve ``sect409r1``. Also called NIST B-409. These binary curves are
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discouraged for new systems.
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.. class:: SECT283R1
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.. versionadded:: 0.5
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SECG curve ``sect283r1``. Also called NIST B-283. These binary curves are
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discouraged for new systems.
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.. class:: SECT233R1
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.. versionadded:: 0.5
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SECG curve ``sect233r1``. Also called NIST B-233. These binary curves are
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discouraged for new systems.
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.. class:: SECT163R2
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.. versionadded:: 0.5
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SECG curve ``sect163r2``. Also called NIST B-163. These binary curves are
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discouraged for new systems.
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Key Interfaces
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~~~~~~~~~~~~~~
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.. class:: EllipticCurve
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.. versionadded:: 0.5
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A named elliptic curve.
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.. attribute:: name
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:type: str
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The name of the curve. Usually the name used for the ASN.1 OID such as
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``secp256k1``.
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.. attribute:: key_size
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:type: int
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Size (in :term:`bits`) of a secret scalar for the curve (as generated
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by :func:`generate_private_key`).
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.. class:: EllipticCurveSignatureAlgorithm
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.. versionadded:: 0.5
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.. versionchanged:: 1.6
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:class:`~cryptography.hazmat.primitives.asymmetric.utils.Prehashed`
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can now be used as an ``algorithm``.
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A signature algorithm for use with elliptic curve keys.
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.. attribute:: algorithm
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:type: :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm` or
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:class:`~cryptography.hazmat.primitives.asymmetric.utils.Prehashed`
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The digest algorithm to be used with the signature scheme.
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.. class:: EllipticCurvePrivateKey
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.. versionadded:: 0.5
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An elliptic curve private key for use with an algorithm such as `ECDSA`_ or
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`EdDSA`_. An elliptic curve private key that is not an
|
|
:term:`opaque key` also implements
|
|
:class:`EllipticCurvePrivateKeyWithSerialization` to provide serialization
|
|
methods.
|
|
|
|
.. method:: exchange(algorithm, peer_public_key)
|
|
|
|
.. versionadded:: 1.1
|
|
|
|
Performs a key exchange operation using the provided algorithm with
|
|
the peer's public key.
|
|
|
|
For most applications the ``shared_key`` should be passed to a key
|
|
derivation function. This allows mixing of additional information into the
|
|
key, derivation of multiple keys, and destroys any structure that may be
|
|
present.
|
|
|
|
:param algorithm: The key exchange algorithm, currently only
|
|
:class:`~cryptography.hazmat.primitives.asymmetric.ec.ECDH` is
|
|
supported.
|
|
:param EllipticCurvePublicKey peer_public_key: The public key for the
|
|
peer.
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|
|
|
:returns bytes: A shared key.
|
|
|
|
.. method:: public_key()
|
|
|
|
:return: :class:`EllipticCurvePublicKey`
|
|
|
|
The EllipticCurvePublicKey object for this private key.
|
|
|
|
.. method:: sign(data, signature_algorithm)
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|
|
|
.. versionadded:: 1.5
|
|
|
|
Sign one block of data which can be verified later by others using the
|
|
public key.
|
|
|
|
:param bytes data: The message string to sign.
|
|
|
|
:param signature_algorithm: An instance of
|
|
:class:`EllipticCurveSignatureAlgorithm`, such as :class:`ECDSA`.
|
|
|
|
:return bytes: Signature.
|
|
|
|
.. attribute:: key_size
|
|
|
|
.. versionadded:: 1.9
|
|
|
|
:type: int
|
|
|
|
Size (in :term:`bits`) of a secret scalar for the curve (as generated
|
|
by :func:`generate_private_key`).
|
|
|
|
|
|
.. class:: EllipticCurvePrivateKeyWithSerialization
|
|
|
|
.. versionadded:: 0.8
|
|
|
|
This interface contains additional methods relating to serialization.
|
|
Any object with this interface also has all the methods from
|
|
:class:`EllipticCurvePrivateKey`.
|
|
|
|
.. method:: private_numbers()
|
|
|
|
Create a :class:`EllipticCurvePrivateNumbers` object.
|
|
|
|
:returns: An :class:`EllipticCurvePrivateNumbers` instance.
|
|
|
|
.. method:: private_bytes(encoding, format, encryption_algorithm)
|
|
|
|
Allows serialization of the key to bytes. Encoding (
|
|
:attr:`~cryptography.hazmat.primitives.serialization.Encoding.PEM` or
|
|
:attr:`~cryptography.hazmat.primitives.serialization.Encoding.DER`),
|
|
format (
|
|
:attr:`~cryptography.hazmat.primitives.serialization.PrivateFormat.TraditionalOpenSSL`
|
|
or
|
|
:attr:`~cryptography.hazmat.primitives.serialization.PrivateFormat.PKCS8`)
|
|
and encryption algorithm (such as
|
|
:class:`~cryptography.hazmat.primitives.serialization.BestAvailableEncryption`
|
|
or :class:`~cryptography.hazmat.primitives.serialization.NoEncryption`)
|
|
are chosen to define the exact serialization.
|
|
|
|
:param encoding: A value from the
|
|
:class:`~cryptography.hazmat.primitives.serialization.Encoding` enum.
|
|
|
|
:param format: A value from the
|
|
:class:`~cryptography.hazmat.primitives.serialization.PrivateFormat` enum.
|
|
|
|
:param encryption_algorithm: An instance of an object conforming to the
|
|
:class:`~cryptography.hazmat.primitives.serialization.KeySerializationEncryption`
|
|
interface.
|
|
|
|
:return bytes: Serialized key.
|
|
|
|
|
|
.. class:: EllipticCurvePublicKey
|
|
|
|
.. versionadded:: 0.5
|
|
|
|
An elliptic curve public key.
|
|
|
|
.. attribute:: curve
|
|
|
|
:type: :class:`EllipticCurve`
|
|
|
|
The elliptic curve for this key.
|
|
|
|
.. method:: public_numbers()
|
|
|
|
Create a :class:`EllipticCurvePublicNumbers` object.
|
|
|
|
:returns: An :class:`EllipticCurvePublicNumbers` instance.
|
|
|
|
.. method:: public_bytes(encoding, format)
|
|
|
|
Allows serialization of the key data to bytes. When encoding the public
|
|
key the encodings (
|
|
:attr:`~cryptography.hazmat.primitives.serialization.Encoding.PEM`,
|
|
:attr:`~cryptography.hazmat.primitives.serialization.Encoding.DER`) and
|
|
format (
|
|
:attr:`~cryptography.hazmat.primitives.serialization.PublicFormat.SubjectPublicKeyInfo`)
|
|
are chosen to define the exact serialization. When encoding the point
|
|
the encoding
|
|
:attr:`~cryptography.hazmat.primitives.serialization.Encoding.X962`
|
|
should be used with the formats (
|
|
:attr:`~cryptography.hazmat.primitives.serialization.PublicFormat.UncompressedPoint`
|
|
or
|
|
:attr:`~cryptography.hazmat.primitives.serialization.PublicFormat.CompressedPoint`
|
|
).
|
|
|
|
:param encoding: A value from the
|
|
:class:`~cryptography.hazmat.primitives.serialization.Encoding` enum.
|
|
|
|
:param format: A value from the
|
|
:class:`~cryptography.hazmat.primitives.serialization.PublicFormat` enum.
|
|
|
|
:return bytes: Serialized data.
|
|
|
|
.. method:: verify(signature, data, signature_algorithm)
|
|
|
|
.. versionadded:: 1.5
|
|
|
|
Verify one block of data was signed by the private key associated
|
|
with this public key.
|
|
|
|
:param bytes signature: The signature to verify.
|
|
|
|
:param bytes data: The message string that was signed.
|
|
|
|
:param signature_algorithm: An instance of
|
|
:class:`EllipticCurveSignatureAlgorithm`.
|
|
|
|
:raises cryptography.exceptions.InvalidSignature: If the signature does
|
|
not validate.
|
|
|
|
.. attribute:: key_size
|
|
|
|
.. versionadded:: 1.9
|
|
|
|
:type: int
|
|
|
|
Size (in :term:`bits`) of a secret scalar for the curve (as generated
|
|
by :func:`generate_private_key`).
|
|
|
|
.. classmethod:: from_encoded_point(curve, data)
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Decodes a byte string as described in `SEC 1 v2.0`_ section 2.3.3 and
|
|
returns an :class:`EllipticCurvePublicKey`. This class method supports
|
|
compressed points.
|
|
|
|
:param curve: An
|
|
:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurve`
|
|
instance.
|
|
|
|
:param bytes data: The serialized point byte string.
|
|
|
|
:returns: An :class:`EllipticCurvePublicKey` instance.
|
|
|
|
:raises ValueError: Raised when an invalid point is supplied.
|
|
|
|
:raises TypeError: Raised when curve is not an
|
|
:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurve`.
|
|
|
|
|
|
.. class:: EllipticCurvePublicKeyWithSerialization
|
|
|
|
.. versionadded:: 0.6
|
|
|
|
Alias for :class:`EllipticCurvePublicKey`.
|
|
|
|
|
|
|
|
Serialization
|
|
~~~~~~~~~~~~~
|
|
|
|
This sample demonstrates how to generate a private key and serialize it.
|
|
|
|
|
|
.. doctest::
|
|
|
|
>>> from cryptography.hazmat.backends import default_backend
|
|
>>> from cryptography.hazmat.primitives import hashes
|
|
>>> from cryptography.hazmat.primitives.asymmetric import ec
|
|
>>> from cryptography.hazmat.primitives import serialization
|
|
|
|
>>> private_key = ec.generate_private_key(ec.SECP384R1(), default_backend())
|
|
|
|
>>> serialized_private = private_key.private_bytes(
|
|
... encoding=serialization.Encoding.PEM,
|
|
... format=serialization.PrivateFormat.PKCS8,
|
|
... encryption_algorithm=serialization.BestAvailableEncryption(b'testpassword')
|
|
... )
|
|
>>> serialized_private.splitlines()[0]
|
|
b'-----BEGIN ENCRYPTED PRIVATE KEY-----'
|
|
|
|
You can also serialize the key without a password, by relying on
|
|
:class:`~cryptography.hazmat.primitives.serialization.NoEncryption`.
|
|
|
|
The public key is serialized as follows:
|
|
|
|
|
|
.. doctest::
|
|
|
|
>>> public_key = private_key.public_key()
|
|
>>> serialized_public = public_key.public_bytes(
|
|
... encoding=serialization.Encoding.PEM,
|
|
... format=serialization.PublicFormat.SubjectPublicKeyInfo
|
|
... )
|
|
>>> serialized_public.splitlines()[0]
|
|
b'-----BEGIN PUBLIC KEY-----'
|
|
|
|
This is the part that you would normally share with the rest of the world.
|
|
|
|
|
|
Key loading
|
|
~~~~~~~~~~~
|
|
|
|
This extends the sample in the previous section, assuming that the variables
|
|
``serialized_private`` and ``serialized_public`` contain the respective keys
|
|
in PEM format.
|
|
|
|
.. doctest::
|
|
|
|
>>> loaded_public_key = serialization.load_pem_public_key(
|
|
... serialized_public,
|
|
... backend=default_backend()
|
|
... )
|
|
|
|
>>> loaded_private_key = serialization.load_pem_private_key(
|
|
... serialized_private,
|
|
... # or password=None, if in plain text
|
|
... password=b'testpassword',
|
|
... backend=default_backend()
|
|
... )
|
|
|
|
|
|
Elliptic Curve Object Identifiers
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
.. class:: EllipticCurveOID
|
|
|
|
.. versionadded:: 2.4
|
|
|
|
.. attribute:: SECP192R1
|
|
|
|
Corresponds to the dotted string ``"1.2.840.10045.3.1.1"``.
|
|
|
|
.. attribute:: SECP224R1
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.33"``.
|
|
|
|
.. attribute:: SECP256K1
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.10"``.
|
|
|
|
.. attribute:: SECP256R1
|
|
|
|
Corresponds to the dotted string ``"1.2.840.10045.3.1.7"``.
|
|
|
|
.. attribute:: SECP384R1
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.34"``.
|
|
|
|
.. attribute:: SECP521R1
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.35"``.
|
|
|
|
.. attribute:: BRAINPOOLP256R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.36.3.3.2.8.1.1.7"``.
|
|
|
|
.. attribute:: BRAINPOOLP384R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.36.3.3.2.8.1.1.11"``.
|
|
|
|
.. attribute:: BRAINPOOLP512R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.36.3.3.2.8.1.1.13"``.
|
|
|
|
.. attribute:: SECT163K1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.1"``.
|
|
|
|
.. attribute:: SECT163R2
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.15"``.
|
|
|
|
.. attribute:: SECT233K1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.26"``.
|
|
|
|
.. attribute:: SECT233R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.27"``.
|
|
|
|
.. attribute:: SECT283K1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.16"``.
|
|
|
|
.. attribute:: SECT283R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.17"``.
|
|
|
|
.. attribute:: SECT409K1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.36"``.
|
|
|
|
.. attribute:: SECT409R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.37"``.
|
|
|
|
.. attribute:: SECT571K1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.38"``.
|
|
|
|
.. attribute:: SECT571R1
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
Corresponds to the dotted string ``"1.3.132.0.39"``.
|
|
|
|
|
|
.. _`FIPS 186-3`: https://csrc.nist.gov/csrc/media/publications/fips/186/3/archive/2009-06-25/documents/fips_186-3.pdf
|
|
.. _`FIPS 186-4`: https://csrc.nist.gov/publications/detail/fips/186/4/final
|
|
.. _`800-56A`: https://csrc.nist.gov/publications/detail/sp/800-56a/revised/archive/2007-03-14
|
|
.. _`800-56Ar2`: https://csrc.nist.gov/publications/detail/sp/800-56a/rev-2/final
|
|
.. _`some concern`: https://crypto.stackexchange.com/questions/10263/should-we-trust-the-nist-recommended-ecc-parameters
|
|
.. _`less than 224 bits`: https://www.cosic.esat.kuleuven.be/ecrypt/ecrypt2/documents/D.SPA.20.pdf
|
|
.. _`elliptic curve diffie-hellman is faster than diffie-hellman`: https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1100&context=cseconfwork
|
|
.. _`minimize the number of security concerns for elliptic-curve cryptography`: https://cr.yp.to/ecdh/curve25519-20060209.pdf
|
|
.. _`SafeCurves`: https://safecurves.cr.yp.to/
|
|
.. _`ECDSA`: https://en.wikipedia.org/wiki/ECDSA
|
|
.. _`EdDSA`: https://en.wikipedia.org/wiki/EdDSA
|
|
.. _`forward secrecy`: https://en.wikipedia.org/wiki/Forward_secrecy
|
|
.. _`SEC 1 v2.0`: http://www.secg.org/sec1-v2.pdf
|