Update cryptography to 3.1

[pyup-bot]

This PR updates cryptography from 2.8 to 3.1.

Changelog

3.1

~~~~~~~~~~~~~~~~

* **BACKWARDS INCOMPATIBLE:** Removed support for ``idna`` based
:term:`U-label` parsing in various X.509 classes. This support was originally
deprecated in version 2.1 and moved to an extra in 2.5.
* Deprecated OpenSSL 1.0.2 support. OpenSSL 1.0.2 is no longer supported by
the OpenSSL project. The next version of ``cryptography`` will drop support
for it.
* Deprecated support for Python 3.5. This version sees very little use and will
be removed in the next release.
* ``backend`` arguments to functions are no longer required and the
default backend will automatically be selected if no ``backend`` is provided.
* Added initial support for parsing certificates from PKCS7 files with
:func:`~cryptography.hazmat.primitives.serialization.pkcs7.load_pem_pkcs7_certificates`
and
:func:`~cryptography.hazmat.primitives.serialization.pkcs7.load_der_pkcs7_certificates`
.
* Calling ``update`` or ``update_into`` on
:class:`~cryptography.hazmat.primitives.ciphers.CipherContext` with ``data``
longer than 2\ :sup:`31` bytes no longer raises an ``OverflowError``. This
also resolves the same issue in :doc:`/fernet`.

.. _v3-0:

3.0

~~~~~~~~~~~~~~~~

* **BACKWARDS INCOMPATIBLE:** Removed support for passing an
:class:`~cryptography.x509.Extension` instance to
:meth:`~cryptography.x509.AuthorityKeyIdentifier.from_issuer_subject_key_identifier`,
as per our deprecation policy.
* **BACKWARDS INCOMPATIBLE:** Support for LibreSSL 2.7.x, 2.8.x, and 2.9.0 has
been removed (2.9.1+ is still supported).
* **BACKWARDS INCOMPATIBLE:** Dropped support for macOS 10.9, macOS users must
upgrade to 10.10 or newer.
* **BACKWARDS INCOMPATIBLE:** RSA
:meth:`~cryptography.hazmat.primitives.asymmetric.rsa.generate_private_key`
no longer accepts ``public_exponent`` values except 65537 and 3 (the latter
for legacy purposes).
* **BACKWARDS INCOMPATIBLE:** X.509 certificate parsing now enforces that the
``version`` field contains a valid value, rather than deferring this check
until :attr:`~cryptography.x509.Certificate.version` is accessed.
* Deprecated support for Python 2. At the time there is no time table for
actually dropping support, however we strongly encourage all users to upgrade
their Python, as Python 2 no longer receives support from the Python core
team.

If you have trouble suppressing this warning in tests view the :ref:`FAQ
entry addressing this issue <faq-howto-handle-deprecation-warning>`.

* Added support for ``OpenSSH`` serialization format for
``ec``, ``ed25519``, ``rsa`` and ``dsa`` private keys:
:func:`~cryptography.hazmat.primitives.serialization.load_ssh_private_key`
for loading and
:attr:`~cryptography.hazmat.primitives.serialization.PrivateFormat.OpenSSH`
for writing.
* Added support for ``OpenSSH`` certificates to
:func:`~cryptography.hazmat.primitives.serialization.load_ssh_public_key`.
* Added :meth:`~cryptography.fernet.Fernet.encrypt_at_time` and
:meth:`~cryptography.fernet.Fernet.decrypt_at_time` to
:class:`~cryptography.fernet.Fernet`.
* Added support for the :class:`~cryptography.x509.SubjectInformationAccess`
X.509 extension.
* Added support for parsing
:class:`~cryptography.x509.SignedCertificateTimestamps` in OCSP responses.
* Added support for parsing attributes in certificate signing requests via
:meth:`~cryptography.x509.CertificateSigningRequest.get_attribute_for_oid`.
* Added support for encoding attributes in certificate signing requests via
:meth:`~cryptography.x509.CertificateSigningRequestBuilder.add_attribute`.
* On OpenSSL 1.1.1d and higher ``cryptography`` now uses OpenSSL's
built-in CSPRNG instead of its own OS random engine because these versions of
OpenSSL properly reseed on fork.
* Added initial support for creating PKCS12 files with
:func:`~cryptography.hazmat.primitives.serialization.pkcs12.serialize_key_and_certificates`.

.. _v2-9-2:

2.9.2

~~~~~~~~~~~~~~~~~~

* Updated the macOS wheel to fix an issue where it would not run on macOS
versions older than 10.15.

.. _v2-9-1:

2.9.1

~~~~~~~~~~~~~~~~~~

* Updated Windows, macOS, and ``manylinux`` wheels to be compiled with
OpenSSL 1.1.1g.

.. _v2-9:

2.9

~~~~~~~~~~~~~~~~

* **BACKWARDS INCOMPATIBLE:** Support for Python 3.4 has been removed due to
low usage and maintenance burden.
* **BACKWARDS INCOMPATIBLE:** Support for OpenSSL 1.0.1 has been removed.
Users on older version of OpenSSL will need to upgrade.
* **BACKWARDS INCOMPATIBLE:** Support for LibreSSL 2.6.x has been removed.
* Removed support for calling
:meth:`~cryptography.hazmat.primitives.asymmetric.x25519.X25519PublicKey.public_bytes`
with no arguments, as per our deprecation policy. You must now pass
``encoding`` and ``format``.
* **BACKWARDS INCOMPATIBLE:** Reversed the order in which
:meth:`~cryptography.x509.Name.rfc4514_string` returns the RDNs
as required by :rfc:`4514`.
* Updated Windows, macOS, and ``manylinux`` wheels to be compiled with
OpenSSL 1.1.1f.
* Added support for parsing
:attr:`~cryptography.x509.ocsp.OCSPResponse.single_extensions` in an OCSP
response.
* :class:`~cryptography.x509.NameAttribute` values can now be empty strings.

.. _v2-8:

Links

• PyPI: https://pypi.org/project/cryptography
• Changelog: https://pyup.io/changelogs/cryptography/
• Repo: https://github.com/pyca/cryptography

[coveralls]

Coverage remained the same at 42.065% when pulling 14f2ead on pyup-update-cryptography-2.8-to-3.1 into 10a4d82 on master.

[pyup-bot]

Closing this in favor of #482