index : iCE40/yosys	master
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	Commit message (Collapse)	Author	Age	Files	Lines
*	Merge remote-tracking branch 'origin/master' into ice40dsp	Eddie Hung	2019-07-18	14	-51/+146
|\
| *	Merge pull request #1184 from whitequark/synth-better-labels	Clifford Wolf	2019-07-18	5	-17/+21
| |\ | | | | | |	synth_{ice40,ecp5}: more sensible pass label naming
| | *	synth_ecp5: rename dram to lutram everywhere.	whitequark	2019-07-16	4	-13/+13
| | |
| | *	synth_{ice40,ecp5}: more sensible pass label naming.	whitequark	2019-07-16	2	-5/+9
| | |
| * |	Merge pull request #1204 from smunaut/fix_1187	David Shah	2019-07-17	2	-4/+4
| |\ \ | | | | | | | |	ice40: Adapt the relut process passes to the new $lut/SB_LUT4 port map
| | * |	ice40: Adapt the relut process passes to the new $lut <=> SB_LUT4 port map	Sylvain Munaut	2019-07-16	2	-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |	The new mapping introduced in 437fec0d88b4a2ad172edf0d1a861a38845f3b1d needed matching adaptation when converting and optimizing LUTs during the relut process Fixes #1187 (Diagnosis of the issue by @daveshah1 on IRC) Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
| * | |	gen_lut to return correctly sized LUT mask	Eddie Hung	2019-07-16	1	-1/+1
| |/ /
| * |	Merge pull request #1186 from YosysHQ/eddie/abc9_ice40_fix	Eddie Hung	2019-07-16	8	-29/+120
| |\ \ | | |/ | |/|	abc9/ice40: encapsulate SB_CARRY+SB_LUT4 into one box
| | *	$__ICE40_CARRY_LUT4 -> $__ICE40_FULL_ADDER as per @whitequark	Eddie Hung	2019-07-15	7	-8/+8
| | |
| | *	ice40_opt to $__ICE40_CARRY_LUT4 into $lut not SB_LUT	Eddie Hung	2019-07-13	1	-9/+7
| | |
| | *	Use Const::from_string() not its constructor...	Eddie Hung	2019-07-12	1	-1/+1
| | |
| | *	Off by one	Eddie Hung	2019-07-12	1	-1/+1
| | |
| | *	Fix spacing	Eddie Hung	2019-07-12	1	-1/+1
| | |
| | *	Remove double push	Eddie Hung	2019-07-12	1	-1/+0
| | |
| | *	Map to and from this box if -abc9	Eddie Hung	2019-07-12	1	-2/+3
| | |
| | *	ice40_opt to handle this box and opt back to SB_LUT4	Eddie Hung	2019-07-12	1	-0/+48
| | |
| | *	Add new box to cells_sim.v	Eddie Hung	2019-07-12	1	-2/+25
| | |
| | *	_ABC macro will map and unmap to this new box	Eddie Hung	2019-07-12	2	-0/+34
| | |
| | *	Combine SB_CARRY+SB_LUT into one $__ICE40_CARRY_LUT4 box	Eddie Hung	2019-07-12	3	-25/+13
| | |
* | |	synth_ice40 to decompose into 16x16	Eddie Hung	2019-07-18	1	-1/+3
| | |
* | |	mul2dsp to create cells that can be interchanged with $mul	Eddie Hung	2019-07-18	1	-1/+7
| | |
* | |	Make consistent	Eddie Hung	2019-07-18	1	-1/+2
| | |
* | |	Fix signed multiplier decomposition	Eddie Hung	2019-07-18	1	-29/+36
| | |
* | |	Use single DSP_SIGNEDONLY macro	Eddie Hung	2019-07-18	1	-1/+1
| | |
* | |	Working for unsigned	Eddie Hung	2019-07-18	1	-52/+28
| | |
* | |	Cleanup	Eddie Hung	2019-07-18	1	-70/+58
| | |
* | |	Merge branch 'xc7dsp' of github.com:YosysHQ/yosys into xc7dsp	Eddie Hung	2019-07-18	1	-31/+41
|\ \ \
| * | |	mul2dsp: Lower partial products always have unsigned inputs	David Shah	2019-07-18	1	-31/+41
| | | | | | | | | | | | | | | |	Signed-off-by: David Shah <dave@ds0.me>
* | | |	Make all operands signed	Eddie Hung	2019-07-17	1	-1/+1
| | | |
* | | |	Update comment	Eddie Hung	2019-07-17	1	-5/+3
|/ / /
* | |	Fix mul2dsp signedness	Eddie Hung	2019-07-17	1	-42/+38
| | |
* | |	A_SIGNED == B_SIGNED so flip both	Eddie Hung	2019-07-17	1	-21/+12
| | |
* | |	Add DSP_{A,B}_SIGNEDONLY macro	Eddie Hung	2019-07-16	1	-11/+40
| | |
* | |	Signedness	Eddie Hung	2019-07-16	2	-8/+8
| | |
* | |	Revert drop down to 24x16 multipliers for all	Eddie Hung	2019-07-16	2	-4/+4
| | |
* | |	Merge branch 'xc7dsp' of github.com:YosysHQ/yosys into xc7dsp	Eddie Hung	2019-07-16	4	-27/+35
|\ \ \
| * | |	xilinx: Add correct signed behaviour to DSP48E1 model	David Shah	2019-07-16	1	-1/+1
| | | | | | | | | | | | | | | |	Signed-off-by: David Shah <dave@ds0.me>
| * | |	xilinx: Treat DSP48E1 as 24x17 unsigned for now (actual behaviour is 25x18 ↵	David Shah	2019-07-16	2	-4/+8
| | | | | | | | | | | | | | | | | | | | | | | |	signed) Signed-off-by: David Shah <dave@ds0.me>
| * | |	mul2dsp: Fix edge case where Y_WIDTH is less than B_WIDTH+`DSP_A_MAXWIDTH	David Shah	2019-07-16	1	-18/+22
| | | | | | | | | | | | | | | |	Signed-off-by: David Shah <dave@ds0.me>
| * | |	mul2dsp: Fix indentation	David Shah	2019-07-16	1	-7/+7
| | | | | | | | | | | | | | | |	Signed-off-by: David Shah <dave@ds0.me>
* | | |	Add support for {A,B,P}REG in DSP48E1	Eddie Hung	2019-07-16	1	-5/+21
| | | |
* | | |	Do not swap if equals	Eddie Hung	2019-07-15	1	-1/+1
| | | |
* | | |	Oops forgot these files	Eddie Hung	2019-07-15	2	-0/+5
| | | |
* | | |	OUT port to Y in generic DSP	Eddie Hung	2019-07-15	2	-3/+3
| | | |
* | | |	Move DSP mapping back out to dsp_map.v	Eddie Hung	2019-07-15	2	-41/+40
|/ / /
* | |	Only swap if B_WIDTH > A_WIDTH	Eddie Hung	2019-07-15	1	-1/+1
| | |
* | |	Tidy up	Eddie Hung	2019-07-15	1	-39/+26
| | |
* | |	Move DSP48E1 model out of cells_xtra, initial multiply one in cells_sim	Eddie Hung	2019-07-15	2	-82/+131
| | |
* | |	Merge remote-tracking branch 'origin/master' into xc7dsp	Eddie Hung	2019-07-15	12	-25/+609
|\| |
| * |	Merge pull request #1183 from whitequark/ice40-always-relut	Clifford Wolf	2019-07-12	1	-11/+5
| |\ \ | | |/ | |/|	synth_ice40: switch -relut to be always on

• [next]

generated by cgit v1.2.3 (git 2.25.1) at 2025-04-09 11:41:36 +0000

# 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 binascii
import datetime
import ipaddress
import os

from pyasn1.codec.der import decoder

from pyasn1_modules import rfc2459

import pytest

import six

from cryptography import utils, x509
from cryptography.exceptions import UnsupportedAlgorithm
from cryptography.hazmat.backends.interfaces import (
    DSABackend, EllipticCurveBackend, RSABackend, X509Backend
)
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import dsa, ec, padding, rsa
from cryptography.hazmat.primitives.asymmetric.utils import (
    decode_dss_signature
)
from cryptography.x509.oid import (
    AuthorityInformationAccessOID, ExtendedKeyUsageOID, ExtensionOID, NameOID
)

from .hazmat.primitives.fixtures_dsa import DSA_KEY_2048
from .hazmat.primitives.fixtures_rsa import RSA_KEY_2048, RSA_KEY_512
from .hazmat.primitives.test_ec import _skip_curve_unsupported
from .utils import load_vectors_from_file


@utils.register_interface(x509.ExtensionType)
class DummyExtension(object):
    oid = x509.ObjectIdentifier("1.2.3.4")


@utils.register_interface(x509.GeneralName)
class FakeGeneralName(object):
    def __init__(self, value):
        self._value = value

    value = utils.read_only_property("_value")


def _load_cert(filename, loader, backend):
    cert = load_vectors_from_file(
        filename=filename,
        loader=lambda pemfile: loader(pemfile.read(), backend),
        mode="rb"
    )
    return cert


@pytest.mark.requires_backend_interface(interface=X509Backend)
class TestCertificateRevocationList(object):
    def test_load_pem_crl(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        assert isinstance(crl, x509.CertificateRevocationList)
        fingerprint = binascii.hexlify(crl.fingerprint(hashes.SHA1()))
        assert fingerprint == b"3234b0cb4c0cedf6423724b736729dcfc9e441ef"
        assert isinstance(crl.signature_hash_algorithm, hashes.SHA256)

    def test_load_der_crl(self, backend):
        crl = _load_cert(
            os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
            x509.load_der_x509_crl,
            backend
        )

        assert isinstance(crl, x509.CertificateRevocationList)
        fingerprint = binascii.hexlify(crl.fingerprint(hashes.SHA1()))
        assert fingerprint == b"dd3db63c50f4c4a13e090f14053227cb1011a5ad"
        assert isinstance(crl.signature_hash_algorithm, hashes.SHA256)

    def test_invalid_pem(self, backend):
        with pytest.raises(ValueError):
            x509.load_pem_x509_crl(b"notacrl", backend)

    def test_invalid_der(self, backend):
        with pytest.raises(ValueError):
            x509.load_der_x509_crl(b"notacrl", backend)

    def test_unknown_signature_algorithm(self, backend):
        crl = _load_cert(
            os.path.join(
                "x509", "custom", "crl_md2_unknown_crit_entry_ext.pem"
            ),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(UnsupportedAlgorithm):
                crl.signature_hash_algorithm()

    def test_issuer(self, backend):
        crl = _load_cert(
            os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
            x509.load_der_x509_crl,
            backend
        )

        assert isinstance(crl.issuer, x509.Name)
        assert list(crl.issuer) == [
            x509.NameAttribute(x509.OID_COUNTRY_NAME, u'US'),
            x509.NameAttribute(
                x509.OID_ORGANIZATION_NAME, u'Test Certificates 2011'
            ),
            x509.NameAttribute(x509.OID_COMMON_NAME, u'Good CA')
        ]
        assert crl.issuer.get_attributes_for_oid(x509.OID_COMMON_NAME) == [
            x509.NameAttribute(x509.OID_COMMON_NAME, u'Good CA')
        ]

    def test_equality(self, backend):
        crl1 = _load_cert(
            os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
            x509.load_der_x509_crl,
            backend
        )

        crl2 = _load_cert(
            os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
            x509.load_der_x509_crl,
            backend
        )

        crl3 = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        assert crl1 == crl2
        assert crl1 != crl3
        assert crl1 != object()

    def test_update_dates(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        assert isinstance(crl.next_update, datetime.datetime)
        assert isinstance(crl.last_update, datetime.datetime)

        assert crl.next_update.isoformat() == "2016-01-01T00:00:00"
        assert crl.last_update.isoformat() == "2015-01-01T00:00:00"

    def test_revoked_cert_retrieval(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        for r in crl:
            assert isinstance(r, x509.RevokedCertificate)

        # Check that len() works for CRLs.
        assert len(crl) == 12

    def test_revoked_cert_retrieval_retain_only_revoked(self, backend):
        """
        This test attempts to trigger the crash condition described in
        https://github.com/pyca/cryptography/issues/2557
        PyPy does gc at its own pace, so it will only be reliable on CPython.
        """
        revoked = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )[11]
        assert revoked.revocation_date == datetime.datetime(2015, 1, 1, 0, 0)
        assert revoked.serial_number == 11

    def test_extensions(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_ian_aia_aki.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        crl_number = crl.extensions.get_extension_for_oid(
            ExtensionOID.CRL_NUMBER
        )
        aki = crl.extensions.get_extension_for_class(
            x509.AuthorityKeyIdentifier
        )
        aia = crl.extensions.get_extension_for_class(
            x509.AuthorityInformationAccess
        )
        ian = crl.extensions.get_extension_for_class(
            x509.IssuerAlternativeName
        )
        assert crl_number.value == x509.CRLNumber(1)
        assert crl_number.critical is False
        assert aki.value == x509.AuthorityKeyIdentifier(
            key_identifier=(
                b'yu\xbb\x84:\xcb,\xdez\t\xbe1\x1bC\xbc\x1c*MSX'
            ),
            authority_cert_issuer=None,
            authority_cert_serial_number=None
        )
        assert aia.value == x509.AuthorityInformationAccess([
            x509.AccessDescription(
                AuthorityInformationAccessOID.CA_ISSUERS,
                x509.DNSName(u"cryptography.io")
            )
        ])
        assert ian.value == x509.IssuerAlternativeName([
            x509.UniformResourceIdentifier(u"https://cryptography.io"),
        ])

    def test_signature(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        assert crl.signature == binascii.unhexlify(
            b"536a5a0794f68267361e7bc2f19167a3e667a2ab141535616855d8deb2ba1af"
            b"9fd4546b1fe76b454eb436af7b28229fedff4634dfc9dd92254266219ae0ea8"
            b"75d9ff972e9a2da23d5945f073da18c50a4265bfed9ca16586347800ef49dd1"
            b"6856d7265f4f3c498a57f04dc04404e2bd2e2ada1f5697057aacef779a18371"
            b"c621edc9a5c2b8ec1716e8fa22feeb7fcec0ce9156c8d344aa6ae8d1a5d99d0"
            b"9386df36307df3b63c83908f4a61a0ff604c1e292ad63b349d1082ddd7ae1b7"
            b"c178bba995523ec6999310c54da5706549797bfb1230f5593ba7b4353dade4f"
            b"d2be13a57580a6eb20b5c4083f000abac3bf32cd8b75f23e4c8f4b3a79e1e2d"
            b"58a472b0"
        )

    def test_tbs_certlist_bytes(self, backend):
        crl = _load_cert(
            os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
            x509.load_der_x509_crl,
            backend
        )

        ca_cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )

        verifier = ca_cert.public_key().verifier(
            crl.signature, padding.PKCS1v15(), crl.signature_hash_algorithm
        )
        verifier.update(crl.tbs_certlist_bytes)
        verifier.verify()

    def test_public_bytes_pem(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_empty.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        # Encode it to PEM and load it back.
        crl = x509.load_pem_x509_crl(crl.public_bytes(
            encoding=serialization.Encoding.PEM,
        ), backend)

        assert len(crl) == 0
        assert crl.last_update == datetime.datetime(2015, 12, 20, 23, 44, 47)
        assert crl.next_update == datetime.datetime(2015, 12, 28, 0, 44, 47)

    def test_public_bytes_der(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        # Encode it to DER and load it back.
        crl = x509.load_der_x509_crl(crl.public_bytes(
            encoding=serialization.Encoding.DER,
        ), backend)

        assert len(crl) == 12
        assert crl.last_update == datetime.datetime(2015, 1, 1, 0, 0, 0)
        assert crl.next_update == datetime.datetime(2016, 1, 1, 0, 0, 0)

    @pytest.mark.parametrize(
        ("cert_path", "loader_func", "encoding"),
        [
            (
                os.path.join("x509", "custom", "crl_all_reasons.pem"),
                x509.load_pem_x509_crl,
                serialization.Encoding.PEM,
            ),
            (
                os.path.join("x509", "PKITS_data", "crls", "GoodCACRL.crl"),
                x509.load_der_x509_crl,
                serialization.Encoding.DER,
            ),
        ]
    )
    def test_public_bytes_match(self, cert_path, loader_func, encoding,
                                backend):
        crl_bytes = load_vectors_from_file(
            cert_path, lambda pemfile: pemfile.read(), mode="rb"
        )
        crl = loader_func(crl_bytes, backend)
        serialized = crl.public_bytes(encoding)
        assert serialized == crl_bytes

    def test_public_bytes_invalid_encoding(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_empty.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(TypeError):
            crl.public_bytes('NotAnEncoding')


@pytest.mark.requires_backend_interface(interface=X509Backend)
class TestRevokedCertificate(object):
    def test_revoked_basics(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        for i, rev in enumerate(crl):
            assert isinstance(rev, x509.RevokedCertificate)
            assert isinstance(rev.serial_number, int)
            assert isinstance(rev.revocation_date, datetime.datetime)
            assert isinstance(rev.extensions, x509.Extensions)

            assert rev.serial_number == i
            assert rev.revocation_date.isoformat() == "2015-01-01T00:00:00"

    def test_revoked_extensions(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        exp_issuer = [
            x509.DirectoryName(x509.Name([
                x509.NameAttribute(x509.OID_COUNTRY_NAME, u"US"),
                x509.NameAttribute(x509.OID_COMMON_NAME, u"cryptography.io"),
            ]))
        ]

        # First revoked cert doesn't have extensions, test if it is handled
        # correctly.
        rev0 = crl[0]
        # It should return an empty Extensions object.
        assert isinstance(rev0.extensions, x509.Extensions)
        assert len(rev0.extensions) == 0
        with pytest.raises(x509.ExtensionNotFound):
            rev0.extensions.get_extension_for_oid(x509.OID_CRL_REASON)
        with pytest.raises(x509.ExtensionNotFound):
            rev0.extensions.get_extension_for_oid(x509.OID_CERTIFICATE_ISSUER)
        with pytest.raises(x509.ExtensionNotFound):
            rev0.extensions.get_extension_for_oid(x509.OID_INVALIDITY_DATE)

        # Test manual retrieval of extension values.
        rev1 = crl[1]
        assert isinstance(rev1.extensions, x509.Extensions)

        reason = rev1.extensions.get_extension_for_class(
            x509.CRLReason).value
        assert reason == x509.CRLReason(x509.ReasonFlags.unspecified)

        issuer = rev1.extensions.get_extension_for_class(
            x509.CertificateIssuer).value
        assert issuer == x509.CertificateIssuer(exp_issuer)

        date = rev1.extensions.get_extension_for_class(
            x509.InvalidityDate).value
        assert date == x509.InvalidityDate(datetime.datetime(2015, 1, 1, 0, 0))

        # Check if all reason flags can be found in the CRL.
        flags = set(x509.ReasonFlags)
        for rev in crl:
            try:
                r = rev.extensions.get_extension_for_class(x509.CRLReason)
            except x509.ExtensionNotFound:
                # Not all revoked certs have a reason extension.
                pass
            else:
                flags.discard(r.value.reason)

        assert len(flags) == 0

    def test_no_revoked_certs(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_empty.pem"),
            x509.load_pem_x509_crl,
            backend
        )
        assert len(crl) == 0

    def test_duplicate_entry_ext(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_dup_entry_ext.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(x509.DuplicateExtension):
            crl[0].extensions

    def test_unsupported_crit_entry_ext(self, backend):
        crl = _load_cert(
            os.path.join(
                "x509", "custom", "crl_md2_unknown_crit_entry_ext.pem"
            ),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(x509.UnsupportedExtension):
            crl[0].extensions

    def test_unsupported_reason(self, backend):
        crl = _load_cert(
            os.path.join(
                "x509", "custom", "crl_unsupported_reason.pem"
            ),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(ValueError):
            crl[0].extensions

    def test_invalid_cert_issuer_ext(self, backend):
        crl = _load_cert(
            os.path.join(
                "x509", "custom", "crl_inval_cert_issuer_entry_ext.pem"
            ),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(ValueError):
            crl[0].extensions

    def test_indexing(self, backend):
        crl = _load_cert(
            os.path.join("x509", "custom", "crl_all_reasons.pem"),
            x509.load_pem_x509_crl,
            backend
        )

        with pytest.raises(IndexError):
            crl[-13]
        with pytest.raises(IndexError):
            crl[12]

        assert crl[-1].serial_number == crl[11].serial_number
        assert len(crl[2:4]) == 2
        assert crl[2:4][0].serial_number == crl[2].serial_number
        assert crl[2:4][1].serial_number == crl[3].serial_number


@pytest.mark.requires_backend_interface(interface=RSABackend)
@pytest.mark.requires_backend_interface(interface=X509Backend)
class TestRSACertificate(object):
    def test_load_pem_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert isinstance(cert, x509.Certificate)
        assert cert.serial == 11559813051657483483
        fingerprint = binascii.hexlify(cert.fingerprint(hashes.SHA1()))
        assert fingerprint == b"2b619ed04bfc9c3b08eb677d272192286a0947a8"
        assert isinstance(cert.signature_hash_algorithm, hashes.SHA1)

    def test_load_der_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )
        assert isinstance(cert, x509.Certificate)
        assert cert.serial == 2
        fingerprint = binascii.hexlify(cert.fingerprint(hashes.SHA1()))
        assert fingerprint == b"6f49779533d565e8b7c1062503eab41492c38e4d"
        assert isinstance(cert.signature_hash_algorithm, hashes.SHA256)

    def test_signature(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert.signature == binascii.unhexlify(
            b"8e0f72fcbebe4755abcaf76c8ce0bae17cde4db16291638e1b1ce04a93cdb4c"
            b"44a3486070986c5a880c14fdf8497e7d289b2630ccb21d24a3d1aa1b2d87482"
            b"07f3a1e16ccdf8daa8a7ea1a33d49774f513edf09270bd8e665b6300a10f003"
            b"66a59076905eb63cf10a81a0ca78a6ef3127f6cb2f6fb7f947fce22a30d8004"
            b"8c243ba2c1a54c425fe12310e8a737638f4920354d4cce25cbd9dea25e6a2fe"
            b"0d8579a5c8d929b9275be221975479f3f75075bcacf09526523b5fd67f7683f"
            b"3cda420fabb1e9e6fc26bc0649cf61bb051d6932fac37066bb16f55903dfe78"
            b"53dc5e505e2a10fbba4f9e93a0d3b53b7fa34b05d7ba6eef869bfc34b8e514f"
            b"d5419f75"
        )
        assert len(cert.signature) == cert.public_key().key_size // 8

    def test_tbs_certificate_bytes(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert.tbs_certificate_bytes == binascii.unhexlify(
            b"308202d8a003020102020900a06cb4b955f7f4db300d06092a864886f70d010"
            b"10505003058310b3009060355040613024155311330110603550408130a536f"
            b"6d652d53746174653121301f060355040a1318496e7465726e6574205769646"
            b"769747320507479204c74643111300f0603550403130848656c6c6f20434130"
            b"1e170d3134313132363231343132305a170d3134313232363231343132305a3"
            b"058310b3009060355040613024155311330110603550408130a536f6d652d53"
            b"746174653121301f060355040a1318496e7465726e657420576964676974732"
            b"0507479204c74643111300f0603550403130848656c6c6f2043413082012230"
            b"0d06092a864886f70d01010105000382010f003082010a0282010100b03af70"
            b"2059e27f1e2284b56bbb26c039153bf81f295b73a49132990645ede4d2da0a9"
            b"13c42e7d38d3589a00d3940d194f6e6d877c2ef812da22a275e83d8be786467"
            b"48b4e7f23d10e873fd72f57a13dec732fc56ab138b1bb308399bb412cd73921"
            b"4ef714e1976e09603405e2556299a05522510ac4574db5e9cb2cf5f99e8f48c"
            b"1696ab3ea2d6d2ddab7d4e1b317188b76a572977f6ece0a4ad396f0150e7d8b"
            b"1a9986c0cb90527ec26ca56e2914c270d2a198b632fa8a2fda55079d3d39864"
            b"b6fb96ddbe331cacb3cb8783a8494ccccd886a3525078847ca01ca5f803e892"
            b"14403e8a4b5499539c0b86f7a0daa45b204a8e079d8a5b03db7ba1ba3d7011a"
            b"70203010001a381bc3081b9301d0603551d0e04160414d8e89dc777e4472656"
            b"f1864695a9f66b7b0400ae3081890603551d23048181307f8014d8e89dc777e"
            b"4472656f1864695a9f66b7b0400aea15ca45a3058310b300906035504061302"
            b"4155311330110603550408130a536f6d652d53746174653121301f060355040"
            b"a1318496e7465726e6574205769646769747320507479204c74643111300f06"
            b"03550403130848656c6c6f204341820900a06cb4b955f7f4db300c0603551d1"
            b"3040530030101ff"
        )
        verifier = cert.public_key().verifier(
            cert.signature, padding.PKCS1v15(), cert.signature_hash_algorithm
        )
        verifier.update(cert.tbs_certificate_bytes)
        verifier.verify()

    def test_issuer(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "Validpre2000UTCnotBeforeDateTest3EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )
        issuer = cert.issuer
        assert isinstance(issuer, x509.Name)
        assert list(issuer) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(
                NameOID.ORGANIZATION_NAME, u'Test Certificates 2011'
            ),
            x509.NameAttribute(NameOID.COMMON_NAME, u'Good CA')
        ]
        assert issuer.get_attributes_for_oid(NameOID.COMMON_NAME) == [
            x509.NameAttribute(NameOID.COMMON_NAME, u'Good CA')
        ]

    def test_all_issuer_name_types(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "custom",
                "all_supported_names.pem"
            ),
            x509.load_pem_x509_certificate,
            backend
        )
        issuer = cert.issuer

        assert isinstance(issuer, x509.Name)
        assert list(issuer) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'CA'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Illinois'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Chicago'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'Zero, LLC'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'One, LLC'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'common name 0'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'common name 1'),
            x509.NameAttribute(NameOID.ORGANIZATIONAL_UNIT_NAME, u'OU 0'),
            x509.NameAttribute(NameOID.ORGANIZATIONAL_UNIT_NAME, u'OU 1'),
            x509.NameAttribute(NameOID.DN_QUALIFIER, u'dnQualifier0'),
            x509.NameAttribute(NameOID.DN_QUALIFIER, u'dnQualifier1'),
            x509.NameAttribute(NameOID.SERIAL_NUMBER, u'123'),
            x509.NameAttribute(NameOID.SERIAL_NUMBER, u'456'),
            x509.NameAttribute(NameOID.TITLE, u'Title 0'),
            x509.NameAttribute(NameOID.TITLE, u'Title 1'),
            x509.NameAttribute(NameOID.SURNAME, u'Surname 0'),
            x509.NameAttribute(NameOID.SURNAME, u'Surname 1'),
            x509.NameAttribute(NameOID.GIVEN_NAME, u'Given Name 0'),
            x509.NameAttribute(NameOID.GIVEN_NAME, u'Given Name 1'),
            x509.NameAttribute(NameOID.PSEUDONYM, u'Incognito 0'),
            x509.NameAttribute(NameOID.PSEUDONYM, u'Incognito 1'),
            x509.NameAttribute(NameOID.GENERATION_QUALIFIER, u'Last Gen'),
            x509.NameAttribute(NameOID.GENERATION_QUALIFIER, u'Next Gen'),
            x509.NameAttribute(NameOID.DOMAIN_COMPONENT, u'dc0'),
            x509.NameAttribute(NameOID.DOMAIN_COMPONENT, u'dc1'),
            x509.NameAttribute(NameOID.EMAIL_ADDRESS, u'test0@test.local'),
            x509.NameAttribute(NameOID.EMAIL_ADDRESS, u'test1@test.local'),
        ]

    def test_subject(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "Validpre2000UTCnotBeforeDateTest3EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )
        subject = cert.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(
                NameOID.ORGANIZATION_NAME, u'Test Certificates 2011'
            ),
            x509.NameAttribute(
                NameOID.COMMON_NAME,
                u'Valid pre2000 UTC notBefore Date EE Certificate Test3'
            )
        ]
        assert subject.get_attributes_for_oid(NameOID.COMMON_NAME) == [
            x509.NameAttribute(
                NameOID.COMMON_NAME,
                u'Valid pre2000 UTC notBefore Date EE Certificate Test3'
            )
        ]

    def test_unicode_name(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "custom",
                "utf8_common_name.pem"
            ),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert.subject.get_attributes_for_oid(NameOID.COMMON_NAME) == [
            x509.NameAttribute(
                NameOID.COMMON_NAME,
                u'We heart UTF8!\u2122'
            )
        ]
        assert cert.issuer.get_attributes_for_oid(NameOID.COMMON_NAME) == [
            x509.NameAttribute(
                NameOID.COMMON_NAME,
                u'We heart UTF8!\u2122'
            )
        ]

    def test_all_subject_name_types(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "custom",
                "all_supported_names.pem"
            ),
            x509.load_pem_x509_certificate,
            backend
        )
        subject = cert.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'AU'),
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'DE'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'California'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'New York'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'San Francisco'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Ithaca'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'Org Zero, LLC'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'Org One, LLC'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'CN 0'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'CN 1'),
            x509.NameAttribute(
                NameOID.ORGANIZATIONAL_UNIT_NAME, u'Engineering 0'
            ),
            x509.NameAttribute(
                NameOID.ORGANIZATIONAL_UNIT_NAME, u'Engineering 1'
            ),
            x509.NameAttribute(NameOID.DN_QUALIFIER, u'qualified0'),
            x509.NameAttribute(NameOID.DN_QUALIFIER, u'qualified1'),
            x509.NameAttribute(NameOID.SERIAL_NUMBER, u'789'),
            x509.NameAttribute(NameOID.SERIAL_NUMBER, u'012'),
            x509.NameAttribute(NameOID.TITLE, u'Title IX'),
            x509.NameAttribute(NameOID.TITLE, u'Title X'),
            x509.NameAttribute(NameOID.SURNAME, u'Last 0'),
            x509.NameAttribute(NameOID.SURNAME, u'Last 1'),
            x509.NameAttribute(NameOID.GIVEN_NAME, u'First 0'),
            x509.NameAttribute(NameOID.GIVEN_NAME, u'First 1'),
            x509.NameAttribute(NameOID.PSEUDONYM, u'Guy Incognito 0'),
            x509.NameAttribute(NameOID.PSEUDONYM, u'Guy Incognito 1'),
            x509.NameAttribute(NameOID.GENERATION_QUALIFIER, u'32X'),
            x509.NameAttribute(NameOID.GENERATION_QUALIFIER, u'Dreamcast'),
            x509.NameAttribute(NameOID.DOMAIN_COMPONENT, u'dc2'),
            x509.NameAttribute(NameOID.DOMAIN_COMPONENT, u'dc3'),
            x509.NameAttribute(NameOID.EMAIL_ADDRESS, u'test2@test.local'),
            x509.NameAttribute(NameOID.EMAIL_ADDRESS, u'test3@test.local'),
        ]

    def test_load_good_ca_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )

        assert cert.not_valid_before == datetime.datetime(2010, 1, 1, 8, 30)
        assert cert.not_valid_after == datetime.datetime(2030, 12, 31, 8, 30)
        assert cert.serial == 2
        public_key = cert.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        assert cert.version is x509.Version.v3
        fingerprint = binascii.hexlify(cert.fingerprint(hashes.SHA1()))
        assert fingerprint == b"6f49779533d565e8b7c1062503eab41492c38e4d"

    def test_utc_pre_2000_not_before_cert(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "Validpre2000UTCnotBeforeDateTest3EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )

        assert cert.not_valid_before == datetime.datetime(1950, 1, 1, 12, 1)

    def test_pre_2000_utc_not_after_cert(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "Invalidpre2000UTCEEnotAfterDateTest7EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )

        assert cert.not_valid_after == datetime.datetime(1999, 1, 1, 12, 1)

    def test_post_2000_utc_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert.not_valid_before == datetime.datetime(
            2014, 11, 26, 21, 41, 20
        )
        assert cert.not_valid_after == datetime.datetime(
            2014, 12, 26, 21, 41, 20
        )

    def test_generalized_time_not_before_cert(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "ValidGeneralizedTimenotBeforeDateTest4EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )
        assert cert.not_valid_before == datetime.datetime(2002, 1, 1, 12, 1)
        assert cert.not_valid_after == datetime.datetime(2030, 12, 31, 8, 30)
        assert cert.version is x509.Version.v3

    def test_generalized_time_not_after_cert(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "ValidGeneralizedTimenotAfterDateTest8EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )
        assert cert.not_valid_before == datetime.datetime(2010, 1, 1, 8, 30)
        assert cert.not_valid_after == datetime.datetime(2050, 1, 1, 12, 1)
        assert cert.version is x509.Version.v3

    def test_invalid_version_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "invalid_version.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        with pytest.raises(x509.InvalidVersion) as exc:
            cert.version

        assert exc.value.parsed_version == 7

    def test_eq(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        cert2 = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert == cert2

    def test_ne(self, backend):
        cert = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        cert2 = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "ValidGeneralizedTimenotAfterDateTest8EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )
        assert cert != cert2
        assert cert != object()

    def test_hash(self, backend):
        cert1 = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        cert2 = _load_cert(
            os.path.join("x509", "custom", "post2000utctime.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        cert3 = _load_cert(
            os.path.join(
                "x509", "PKITS_data", "certs",
                "ValidGeneralizedTimenotAfterDateTest8EE.crt"
            ),
            x509.load_der_x509_certificate,
            backend
        )

        assert hash(cert1) == hash(cert2)
        assert hash(cert1) != hash(cert3)

    def test_version_1_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "v1_cert.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        assert cert.version is x509.Version.v1

    def test_invalid_pem(self, backend):
        with pytest.raises(ValueError):
            x509.load_pem_x509_certificate(b"notacert", backend)

    def test_invalid_der(self, backend):
        with pytest.raises(ValueError):
            x509.load_der_x509_certificate(b"notacert", backend)

    def test_unsupported_signature_hash_algorithm_cert(self, backend):
        cert = _load_cert(
            os.path.join("x509", "verisign_md2_root.pem"),
            x509.load_pem_x509_certificate,
            backend
        )
        with pytest.raises(UnsupportedAlgorithm):
            cert.signature_hash_algorithm

    def test_public_bytes_pem(self, backend):
        # Load an existing certificate.
        cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )

        # Encode it to PEM and load it back.
        cert = x509.load_pem_x509_certificate(cert.public_bytes(
            encoding=serialization.Encoding.PEM,
        ), backend)

        # We should recover what we had to start with.
        assert cert.not_valid_before == datetime.datetime(2010, 1, 1, 8, 30)
        assert cert.not_valid_after == datetime.datetime(2030, 12, 31, 8, 30)
        assert cert.serial == 2
        public_key = cert.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        assert cert.version is x509.Version.v3
        fingerprint = binascii.hexlify(cert.fingerprint(hashes.SHA1()))
        assert fingerprint == b"6f49779533d565e8b7c1062503eab41492c38e4d"

    def test_public_bytes_der(self, backend):
        # Load an existing certificate.
        cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )

        # Encode it to DER and load it back.
        cert = x509.load_der_x509_certificate(cert.public_bytes(
            encoding=serialization.Encoding.DER,
        ), backend)

        # We should recover what we had to start with.
        assert cert.not_valid_before == datetime.datetime(2010, 1, 1, 8, 30)
        assert cert.not_valid_after == datetime.datetime(2030, 12, 31, 8, 30)
        assert cert.serial == 2
        public_key = cert.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        assert cert.version is x509.Version.v3
        fingerprint = binascii.hexlify(cert.fingerprint(hashes.SHA1()))
        assert fingerprint == b"6f49779533d565e8b7c1062503eab41492c38e4d"

    def test_public_bytes_invalid_encoding(self, backend):
        cert = _load_cert(
            os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
            x509.load_der_x509_certificate,
            backend
        )

        with pytest.raises(TypeError):
            cert.public_bytes('NotAnEncoding')

    @pytest.mark.parametrize(
        ("cert_path", "loader_func", "encoding"),
        [
            (
                os.path.join("x509", "v1_cert.pem"),
                x509.load_pem_x509_certificate,
                serialization.Encoding.PEM,
            ),
            (
                os.path.join("x509", "PKITS_data", "certs", "GoodCACert.crt"),
                x509.load_der_x509_certificate,
                serialization.Encoding.DER,
            ),
        ]
    )
    def test_public_bytes_match(self, cert_path, loader_func, encoding,
                                backend):
        cert_bytes = load_vectors_from_file(
            cert_path, lambda pemfile: pemfile.read(), mode="rb"
        )
        cert = loader_func(cert_bytes, backend)
        serialized = cert.public_bytes(encoding)
        assert serialized == cert_bytes

    def test_certificate_repr(self, backend):
        cert = _load_cert(
            os.path.join(
                "x509", "cryptography.io.pem"
            ),
            x509.load_pem_x509_certificate,
            backend
        )
        if six.PY3:
            assert repr(cert) == (
                "<Certificate(subject=<Name([<NameAttribute(oid=<ObjectIdentif"
                "ier(oid=2.5.4.11, name=organizationalUnitName)>, value='GT487"
                "42965')>, <NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.11, "
                "name=organizationalUnitName)>, value='See www.rapidssl.com/re"
                "sources/cps (c)14')>, <NameAttribute(oid=<ObjectIdentifier(oi"
                "d=2.5.4.11, name=organizationalUnitName)>, value='Domain Cont"
                "rol Validated - RapidSSL(R)')>, <NameAttribute(oid=<ObjectIde"
                "ntifier(oid=2.5.4.3, name=commonName)>, value='www.cryptograp"
                "hy.io')>])>, ...)>"
            )
        else:
            assert repr(cert) == (
                "<Certificate(subject=<Name([<NameAttribute(oid=<ObjectIdentif"
                "ier(oid=2.5.4.11, name=organizationalUnitName)>, value=u'GT48"
                "742965')>, <NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.11,"
                " name=organizationalUnitName)>, value=u'See www.rapidssl.com/"
                "resources/cps (c)14')>, <NameAttribute(oid=<ObjectIdentifier("
                "oid=2.5.4.11, name=organizationalUnitName)>, value=u'Domain C"
                "ontrol Validated - RapidSSL(R)')>, <NameAttribute(oid=<Object"
                "Identifier(oid=2.5.4.3, name=commonName)>, value=u'www.crypto"
                "graphy.io')>])>, ...)>"
            )


@pytest.mark.requires_backend_interface(interface=RSABackend)
@pytest.mark.requires_backend_interface(interface=X509Backend)
class TestRSACertificateRequest(object):
    @pytest.mark.parametrize(
        ("path", "loader_func"),
        [
            [
                os.path.join("x509", "requests", "rsa_sha1.pem"),
                x509.load_pem_x509_csr
            ],
            [
                os.path.join("x509", "requests", "rsa_sha1.der"),
                x509.load_der_x509_csr
            ],
        ]
    )
    def test_load_rsa_certificate_request(self, path, loader_func, backend):
        request = _load_cert(path, loader_func, backend)
        assert isinstance(request.signature_hash_algorithm, hashes.SHA1)
        public_key = request.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        subject = request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'cryptography.io'),
        ]
        extensions = request.extensions
        assert isinstance(extensions, x509.Extensions)
        assert list(extensions) == []

    @pytest.mark.parametrize(
        "loader_func",
        [x509.load_pem_x509_csr, x509.load_der_x509_csr]
    )
    def test_invalid_certificate_request(self, loader_func, backend):
        with pytest.raises(ValueError):
            loader_func(b"notacsr", backend)

    def test_unsupported_signature_hash_algorithm_request(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_md4.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        with pytest.raises(UnsupportedAlgorithm):
            request.signature_hash_algorithm

    def test_duplicate_extension(self, backend):
        request = _load_cert(
            os.path.join(
                "x509", "requests", "two_basic_constraints.pem"
            ),
            x509.load_pem_x509_csr,
            backend
        )
        with pytest.raises(x509.DuplicateExtension) as exc:
            request.extensions

        assert exc.value.oid == ExtensionOID.BASIC_CONSTRAINTS

    def test_unsupported_critical_extension(self, backend):
        request = _load_cert(
            os.path.join(
                "x509", "requests", "unsupported_extension_critical.pem"
            ),
            x509.load_pem_x509_csr,
            backend
        )
        with pytest.raises(x509.UnsupportedExtension) as exc:
            request.extensions

        assert exc.value.oid == x509.ObjectIdentifier('1.2.3.4')

    def test_unsupported_extension(self, backend):
        request = _load_cert(
            os.path.join(
                "x509", "requests", "unsupported_extension.pem"
            ),
            x509.load_pem_x509_csr,
            backend
        )
        extensions = request.extensions
        assert len(extensions) == 1
        assert extensions[0].oid == x509.ObjectIdentifier("1.2.3.4")
        assert extensions[0].value == x509.UnrecognizedExtension(
            x509.ObjectIdentifier("1.2.3.4"), b"value"
        )

    def test_request_basic_constraints(self, backend):
        request = _load_cert(
            os.path.join(
                "x509", "requests", "basic_constraints.pem"
            ),
            x509.load_pem_x509_csr,
            backend
        )
        extensions = request.extensions
        assert isinstance(extensions, x509.Extensions)
        assert list(extensions) == [
            x509.Extension(
                ExtensionOID.BASIC_CONSTRAINTS,
                True,
                x509.BasicConstraints(ca=True, path_length=1),
            ),
        ]

    def test_subject_alt_name(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "san_rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend,
        )
        ext = request.extensions.get_extension_for_oid(
            ExtensionOID.SUBJECT_ALTERNATIVE_NAME
        )
        assert list(ext.value) == [
            x509.DNSName(u"cryptography.io"),
            x509.DNSName(u"sub.cryptography.io"),
        ]

    def test_public_bytes_pem(self, backend):
        # Load an existing CSR.
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        # Encode it to PEM and load it back.
        request = x509.load_pem_x509_csr(request.public_bytes(
            encoding=serialization.Encoding.PEM,
        ), backend)

        # We should recover what we had to start with.
        assert isinstance(request.signature_hash_algorithm, hashes.SHA1)
        public_key = request.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        subject = request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'cryptography.io'),
        ]

    def test_public_bytes_der(self, backend):
        # Load an existing CSR.
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        # Encode it to DER and load it back.
        request = x509.load_der_x509_csr(request.public_bytes(
            encoding=serialization.Encoding.DER,
        ), backend)

        # We should recover what we had to start with.
        assert isinstance(request.signature_hash_algorithm, hashes.SHA1)
        public_key = request.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        subject = request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'cryptography.io'),
        ]

    def test_signature(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        assert request.signature == binascii.unhexlify(
            b"8364c86ffbbfe0bfc9a21f831256658ca8989741b80576d36f08a934603a43b1"
            b"837246d00167a518abb1de7b51a1e5b7ebea14944800818b1a923c804f120a0d"
            b"624f6310ef79e8612755c2b01dcc7f59dfdbce0db3f2630f185f504b8c17af80"
            b"cbd364fa5fda68337153930948226cd4638287a0aed6524d3006885c19028a1e"
            b"e2f5a91d6e77dbaa0b49996ee0a0c60b55b61bd080a08bb34aa7f3e07e91f37f"
            b"6a11645be2d8654c1570dcda145ed7cc92017f7d53225d7f283f3459ec5bda41"
            b"cf6dd75d43676c543483385226b7e4fa29c8739f1b0eaf199613593991979862"
            b"e36181e8c4c270c354b7f52c128db1b70639823324c7ea24791b7bc3d7005f3b"
        )

    def test_tbs_certrequest_bytes(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        assert request.tbs_certrequest_bytes == binascii.unhexlify(
            b"308201840201003057310b3009060355040613025553310e300c060355040813"
            b"055465786173310f300d0603550407130641757374696e310d300b060355040a"
            b"130450794341311830160603550403130f63727970746f6772617068792e696f"
            b"30820122300d06092a864886f70d01010105000382010f003082010a02820101"
            b"00a840a78460cb861066dfa3045a94ba6cf1b7ab9d24c761cffddcc2cb5e3f1d"
            b"c3e4be253e7039ef14fe9d6d2304f50d9f2e1584c51530ab75086f357138bff7"
            b"b854d067d1d5f384f1f2f2c39cc3b15415e2638554ef8402648ae3ef08336f22"
            b"b7ecc6d4331c2b21c3091a7f7a9518180754a646640b60419e4cc6f5c798110a"
            b"7f030a639fe87e33b4776dfcd993940ec776ab57a181ad8598857976dc303f9a"
            b"573ca619ab3fe596328e92806b828683edc17cc256b41948a2bfa8d047d2158d"
            b"3d8e069aa05fa85b3272abb1c4b4422b6366f3b70e642377b145cd6259e5d3e7"
            b"db048d51921e50766a37b1b130ee6b11f507d20a834001e8de16a92c14f2e964"
            b"a30203010001a000"
        )
        verifier = request.public_key().verifier(
            request.signature,
            padding.PKCS1v15(),
            request.signature_hash_algorithm
        )
        verifier.update(request.tbs_certrequest_bytes)
        verifier.verify()

    def test_public_bytes_invalid_encoding(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        with pytest.raises(TypeError):
            request.public_bytes('NotAnEncoding')

    def test_signature_invalid(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "invalid_signature.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        assert not request.is_signature_valid

    def test_signature_valid(self, backend):
        request = _load_cert(
            os.path.join("x509", "requests", "rsa_sha256.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        assert request.is_signature_valid

    @pytest.mark.parametrize(
        ("request_path", "loader_func", "encoding"),
        [
            (
                os.path.join("x509", "requests", "rsa_sha1.pem"),
                x509.load_pem_x509_csr,
                serialization.Encoding.PEM,
            ),
            (
                os.path.join("x509", "requests", "rsa_sha1.der"),
                x509.load_der_x509_csr,
                serialization.Encoding.DER,
            ),
        ]
    )
    def test_public_bytes_match(self, request_path, loader_func, encoding,
                                backend):
        request_bytes = load_vectors_from_file(
            request_path, lambda pemfile: pemfile.read(), mode="rb"
        )
        request = loader_func(request_bytes, backend)
        serialized = request.public_bytes(encoding)
        assert serialized == request_bytes

    def test_eq(self, backend):
        request1 = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        request2 = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        assert request1 == request2

    def test_ne(self, backend):
        request1 = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        request2 = _load_cert(
            os.path.join("x509", "requests", "san_rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        assert request1 != request2
        assert request1 != object()

    def test_hash(self, backend):
        request1 = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        request2 = _load_cert(
            os.path.join("x509", "requests", "rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )
        request3 = _load_cert(
            os.path.join("x509", "requests", "san_rsa_sha1.pem"),
            x509.load_pem_x509_csr,
            backend
        )

        assert hash(request1) == hash(request2)
        assert hash(request1) != hash(request3)

    def test_build_cert(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'cryptography.io'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            x509.NameAttribute(NameOID.COMMON_NAME, u'cryptography.io'),
        ])).public_key(
            subject_private_key.public_key()
        ).add_extension(
            x509.BasicConstraints(ca=False, path_length=None), True,
        ).add_extension(
            x509.SubjectAlternativeName([x509.DNSName(u"cryptography.io")]),
            critical=False,
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        )

        cert = builder.sign(issuer_private_key, hashes.SHA1(), backend)

        assert cert.version is x509.Version.v3
        assert cert.not_valid_before == not_valid_before
        assert cert.not_valid_after == not_valid_after
        basic_constraints = cert.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.ca is False
        assert basic_constraints.value.path_length is None
        subject_alternative_name = cert.extensions.get_extension_for_oid(
            ExtensionOID.SUBJECT_ALTERNATIVE_NAME
        )
        assert list(subject_alternative_name.value) == [
            x509.DNSName(u"cryptography.io"),
        ]

    def test_build_cert_printable_string_country_name(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        )

        cert = builder.sign(issuer_private_key, hashes.SHA256(), backend)

        parsed, _ = decoder.decode(
            cert.public_bytes(serialization.Encoding.DER),
            asn1Spec=rfc2459.Certificate()
        )
        tbs_cert = parsed.getComponentByName('tbsCertificate')
        subject = tbs_cert.getComponentByName('subject')
        issuer = tbs_cert.getComponentByName('issuer')
        # \x13 is printable string. The first byte of the value of the
        # node corresponds to the ASN.1 string type.
        assert subject[0][0][0][1][0] == b"\x13"[0]
        assert issuer[0][0][0][1][0] == b"\x13"[0]


class TestCertificateBuilder(object):
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_checks_for_unsupported_extensions(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            private_key.public_key()
        ).serial_number(
            777
        ).not_valid_before(
            datetime.datetime(1999, 1, 1)
        ).not_valid_after(
            datetime.datetime(2020, 1, 1)
        ).add_extension(
            DummyExtension(), False
        )

        with pytest.raises(NotImplementedError):
            builder.sign(private_key, hashes.SHA1(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_encode_nonstandard_aia(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        aia = x509.AuthorityInformationAccess([
            x509.AccessDescription(
                x509.ObjectIdentifier("2.999.7"),
                x509.UniformResourceIdentifier(u"http://example.com")
            ),
        ])

        builder = x509.CertificateBuilder().subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            private_key.public_key()
        ).serial_number(
            777
        ).not_valid_before(
            datetime.datetime(1999, 1, 1)
        ).not_valid_after(
            datetime.datetime(2020, 1, 1)
        ).add_extension(
            aia, False
        )

        builder.sign(private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_subject_name(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_issuer_name(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().serial_number(
            777
        ).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_public_key(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_not_valid_before(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_not_valid_after(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_no_serial_number(self, backend):
        subject_private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder().issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )
        with pytest.raises(ValueError):
            builder.sign(subject_private_key, hashes.SHA256(), backend)

    def test_issuer_name_must_be_a_name_type(self):
        builder = x509.CertificateBuilder()

        with pytest.raises(TypeError):
            builder.issuer_name("subject")

        with pytest.raises(TypeError):
            builder.issuer_name(object)

    def test_issuer_name_may_only_be_set_once(self):
        name = x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])
        builder = x509.CertificateBuilder().issuer_name(name)

        with pytest.raises(ValueError):
            builder.issuer_name(name)

    def test_subject_name_must_be_a_name_type(self):
        builder = x509.CertificateBuilder()

        with pytest.raises(TypeError):
            builder.subject_name("subject")

        with pytest.raises(TypeError):
            builder.subject_name(object)

    def test_subject_name_may_only_be_set_once(self):
        name = x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])
        builder = x509.CertificateBuilder().subject_name(name)

        with pytest.raises(ValueError):
            builder.subject_name(name)

    def test_not_valid_before_after_not_valid_after(self):
        builder = x509.CertificateBuilder()

        builder = builder.not_valid_after(
            datetime.datetime(2002, 1, 1, 12, 1)
        )
        with pytest.raises(ValueError):
            builder.not_valid_before(
                datetime.datetime(2003, 1, 1, 12, 1)
            )

    def test_not_valid_after_before_not_valid_before(self):
        builder = x509.CertificateBuilder()

        builder = builder.not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        )
        with pytest.raises(ValueError):
            builder.not_valid_after(
                datetime.datetime(2001, 1, 1, 12, 1)
            )

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_public_key_must_be_public_key(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder()

        with pytest.raises(TypeError):
            builder.public_key(private_key)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_public_key_may_only_be_set_once(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)
        public_key = private_key.public_key()
        builder = x509.CertificateBuilder().public_key(public_key)

        with pytest.raises(ValueError):
            builder.public_key(public_key)

    def test_serial_number_must_be_an_integer_type(self):
        with pytest.raises(TypeError):
            x509.CertificateBuilder().serial_number(10.0)

    def test_serial_number_must_be_non_negative(self):
        with pytest.raises(ValueError):
            x509.CertificateBuilder().serial_number(-10)

    def test_serial_number_must_be_less_than_160_bits_long(self):
        with pytest.raises(ValueError):
            # 2 raised to the 160th power is actually 161 bits
            x509.CertificateBuilder().serial_number(2 ** 160)

    def test_serial_number_may_only_be_set_once(self):
        builder = x509.CertificateBuilder().serial_number(10)

        with pytest.raises(ValueError):
            builder.serial_number(20)

    def test_invalid_not_valid_after(self):
        with pytest.raises(TypeError):
            x509.CertificateBuilder().not_valid_after(104204304504)

        with pytest.raises(TypeError):
            x509.CertificateBuilder().not_valid_after(datetime.time())

        with pytest.raises(ValueError):
            x509.CertificateBuilder().not_valid_after(
                datetime.datetime(1960, 8, 10)
            )

    def test_not_valid_after_may_only_be_set_once(self):
        builder = x509.CertificateBuilder().not_valid_after(
            datetime.datetime.now()
        )

        with pytest.raises(ValueError):
            builder.not_valid_after(
                datetime.datetime.now()
            )

    def test_invalid_not_valid_before(self):
        with pytest.raises(TypeError):
            x509.CertificateBuilder().not_valid_before(104204304504)

        with pytest.raises(TypeError):
            x509.CertificateBuilder().not_valid_before(datetime.time())

        with pytest.raises(ValueError):
            x509.CertificateBuilder().not_valid_before(
                datetime.datetime(1960, 8, 10)
            )

    def test_not_valid_before_may_only_be_set_once(self):
        builder = x509.CertificateBuilder().not_valid_before(
            datetime.datetime.now()
        )

        with pytest.raises(ValueError):
            builder.not_valid_before(
                datetime.datetime.now()
            )

    def test_add_extension_checks_for_duplicates(self):
        builder = x509.CertificateBuilder().add_extension(
            x509.BasicConstraints(ca=False, path_length=None), True,
        )

        with pytest.raises(ValueError):
            builder.add_extension(
                x509.BasicConstraints(ca=False, path_length=None), True,
            )

    def test_add_invalid_extension_type(self):
        builder = x509.CertificateBuilder()

        with pytest.raises(TypeError):
            builder.add_extension(object(), False)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_sign_with_unsupported_hash(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)
        builder = x509.CertificateBuilder()
        builder = builder.subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).serial_number(
            1
        ).public_key(
            private_key.public_key()
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2032, 1, 1, 12, 1)
        )

        with pytest.raises(TypeError):
            builder.sign(private_key, object(), backend)

    @pytest.mark.parametrize(
        "cdp",
        [
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=None,
                    relative_name=x509.Name([
                        x509.NameAttribute(
                            NameOID.COMMON_NAME,
                            u"indirect CRL for indirectCRL CA3"
                        ),
                    ]),
                    reasons=None,
                    crl_issuer=[x509.DirectoryName(
                        x509.Name([
                            x509.NameAttribute(NameOID.COUNTRY_NAME, u"US"),
                            x509.NameAttribute(
                                NameOID.ORGANIZATION_NAME,
                                u"Test Certificates 2011"
                            ),
                            x509.NameAttribute(
                                NameOID.ORGANIZATIONAL_UNIT_NAME,
                                u"indirectCRL CA3 cRLIssuer"
                            ),
                        ])
                    )],
                )
            ]),
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=[x509.DirectoryName(
                        x509.Name([
                            x509.NameAttribute(NameOID.COUNTRY_NAME, u"US"),
                        ])
                    )],
                    relative_name=None,
                    reasons=None,
                    crl_issuer=[x509.DirectoryName(
                        x509.Name([
                            x509.NameAttribute(
                                NameOID.ORGANIZATION_NAME,
                                u"cryptography Testing"
                            ),
                        ])
                    )],
                )
            ]),
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=[
                        x509.UniformResourceIdentifier(
                            u"http://myhost.com/myca.crl"
                        ),
                        x509.UniformResourceIdentifier(
                            u"http://backup.myhost.com/myca.crl"
                        )
                    ],
                    relative_name=None,
                    reasons=frozenset([
                        x509.ReasonFlags.key_compromise,
                        x509.ReasonFlags.ca_compromise
                    ]),
                    crl_issuer=[x509.DirectoryName(
                        x509.Name([
                            x509.NameAttribute(NameOID.COUNTRY_NAME, u"US"),
                            x509.NameAttribute(
                                NameOID.COMMON_NAME, u"cryptography CA"
                            ),
                        ])
                    )],
                )
            ]),
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=[x509.UniformResourceIdentifier(
                        u"http://domain.com/some.crl"
                    )],
                    relative_name=None,
                    reasons=frozenset([
                        x509.ReasonFlags.key_compromise,
                        x509.ReasonFlags.ca_compromise,
                        x509.ReasonFlags.affiliation_changed,
                        x509.ReasonFlags.superseded,
                        x509.ReasonFlags.privilege_withdrawn,
                        x509.ReasonFlags.cessation_of_operation,
                        x509.ReasonFlags.aa_compromise,
                        x509.ReasonFlags.certificate_hold,
                    ]),
                    crl_issuer=None
                )
            ]),
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=None,
                    relative_name=None,
                    reasons=None,
                    crl_issuer=[x509.DirectoryName(
                        x509.Name([
                            x509.NameAttribute(
                                NameOID.COMMON_NAME, u"cryptography CA"
                            ),
                        ])
                    )],
                )
            ]),
            x509.CRLDistributionPoints([
                x509.DistributionPoint(
                    full_name=[x509.UniformResourceIdentifier(
                        u"http://domain.com/some.crl"
                    )],
                    relative_name=None,
                    reasons=frozenset([x509.ReasonFlags.aa_compromise]),
                    crl_issuer=None
                )
            ])
        ]
    )
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_crl_distribution_points(self, backend, cdp):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        builder = x509.CertificateBuilder().serial_number(
            4444444
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.LOCALITY_NAME, u'Austin'),
        ])).public_key(
            subject_private_key.public_key()
        ).add_extension(
            cdp,
            critical=False,
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        )

        cert = builder.sign(issuer_private_key, hashes.SHA1(), backend)

        ext = cert.extensions.get_extension_for_oid(
            ExtensionOID.CRL_DISTRIBUTION_POINTS
        )
        assert ext.critical is False
        assert ext.value == cdp

    @pytest.mark.requires_backend_interface(interface=DSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_build_cert_with_dsa_private_key(self, backend):
        if backend._lib.OPENSSL_VERSION_NUMBER < 0x10001000:
            pytest.skip("Requires a newer OpenSSL. Must be >= 1.0.1")

        issuer_private_key = DSA_KEY_2048.private_key(backend)
        subject_private_key = DSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).add_extension(
            x509.BasicConstraints(ca=False, path_length=None), True,
        ).add_extension(
            x509.SubjectAlternativeName([x509.DNSName(u"cryptography.io")]),
            critical=False,
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        )

        cert = builder.sign(issuer_private_key, hashes.SHA1(), backend)

        assert cert.version is x509.Version.v3
        assert cert.not_valid_before == not_valid_before
        assert cert.not_valid_after == not_valid_after
        basic_constraints = cert.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.ca is False
        assert basic_constraints.value.path_length is None
        subject_alternative_name = cert.extensions.get_extension_for_oid(
            ExtensionOID.SUBJECT_ALTERNATIVE_NAME
        )
        assert list(subject_alternative_name.value) == [
            x509.DNSName(u"cryptography.io"),
        ]

    @pytest.mark.requires_backend_interface(interface=EllipticCurveBackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_build_cert_with_ec_private_key(self, backend):
        if backend._lib.OPENSSL_VERSION_NUMBER < 0x10001000:
            pytest.skip("Requires a newer OpenSSL. Must be >= 1.0.1")

        _skip_curve_unsupported(backend, ec.SECP256R1())
        issuer_private_key = ec.generate_private_key(ec.SECP256R1(), backend)
        subject_private_key = ec.generate_private_key(ec.SECP256R1(), backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).add_extension(
            x509.BasicConstraints(ca=False, path_length=None), True,
        ).add_extension(
            x509.SubjectAlternativeName([x509.DNSName(u"cryptography.io")]),
            critical=False,
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        )

        cert = builder.sign(issuer_private_key, hashes.SHA1(), backend)

        assert cert.version is x509.Version.v3
        assert cert.not_valid_before == not_valid_before
        assert cert.not_valid_after == not_valid_after
        basic_constraints = cert.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.ca is False
        assert basic_constraints.value.path_length is None
        subject_alternative_name = cert.extensions.get_extension_for_oid(
            ExtensionOID.SUBJECT_ALTERNATIVE_NAME
        )
        assert list(subject_alternative_name.value) == [
            x509.DNSName(u"cryptography.io"),
        ]

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_build_cert_with_rsa_key_too_small(self, backend):
        issuer_private_key = RSA_KEY_512.private_key(backend)
        subject_private_key = RSA_KEY_512.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        builder = x509.CertificateBuilder().serial_number(
            777
        ).issuer_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).subject_name(x509.Name([
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ])).public_key(
            subject_private_key.public_key()
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        )

        with pytest.raises(ValueError):
            builder.sign(issuer_private_key, hashes.SHA512(), backend)

    @pytest.mark.parametrize(
        "cp",
        [
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    [u"http://other.com/cps"]
                )
            ]),
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    None
                )
            ]),
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    [
                        u"http://example.com/cps",
                        u"http://other.com/cps",
                        x509.UserNotice(
                            x509.NoticeReference(u"my org", [1, 2, 3, 4]),
                            u"thing"
                        )
                    ]
                )
            ]),
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    [
                        u"http://example.com/cps",
                        x509.UserNotice(
                            x509.NoticeReference(u"UTF8\u2122'", [1, 2, 3, 4]),
                            u"We heart UTF8!\u2122"
                        )
                    ]
                )
            ]),
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    [x509.UserNotice(None, u"thing")]
                )
            ]),
            x509.CertificatePolicies([
                x509.PolicyInformation(
                    x509.ObjectIdentifier("2.16.840.1.12345.1.2.3.4.1"),
                    [
                        x509.UserNotice(
                            x509.NoticeReference(u"my org", [1, 2, 3, 4]),
                            None
                        )
                    ]
                )
            ])
        ]
    )
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_certificate_policies(self, cp, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(x509.OID_COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(x509.OID_COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            cp, critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(
            x509.OID_CERTIFICATE_POLICIES
        )
        assert ext.value == cp

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_issuer_alt_name(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            x509.IssuerAlternativeName([
                x509.DNSName(u"myissuer"),
                x509.RFC822Name(u"email@domain.com"),
            ]), critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(
            ExtensionOID.ISSUER_ALTERNATIVE_NAME
        )
        assert ext.critical is False
        assert ext.value == x509.IssuerAlternativeName([
            x509.DNSName(u"myissuer"),
            x509.RFC822Name(u"email@domain.com"),
        ])

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_extended_key_usage(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            x509.ExtendedKeyUsage([
                ExtendedKeyUsageOID.CLIENT_AUTH,
                ExtendedKeyUsageOID.SERVER_AUTH,
                ExtendedKeyUsageOID.CODE_SIGNING,
            ]), critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        eku = cert.extensions.get_extension_for_oid(
            ExtensionOID.EXTENDED_KEY_USAGE
        )
        assert eku.critical is False
        assert eku.value == x509.ExtendedKeyUsage([
            ExtendedKeyUsageOID.CLIENT_AUTH,
            ExtendedKeyUsageOID.SERVER_AUTH,
            ExtendedKeyUsageOID.CODE_SIGNING,
        ])

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_inhibit_any_policy(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            x509.InhibitAnyPolicy(3), critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(
            ExtensionOID.INHIBIT_ANY_POLICY
        )
        assert ext.value == x509.InhibitAnyPolicy(3)

    @pytest.mark.parametrize(
        "pc",
        [
            x509.PolicyConstraints(
                require_explicit_policy=None,
                inhibit_policy_mapping=1
            ),
            x509.PolicyConstraints(
                require_explicit_policy=3,
                inhibit_policy_mapping=1
            ),
            x509.PolicyConstraints(
                require_explicit_policy=0,
                inhibit_policy_mapping=None
            ),
        ]
    )
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_policy_constraints(self, backend, pc):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            pc, critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_class(
            x509.PolicyConstraints
        )
        assert ext.critical is False
        assert ext.value == pc

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_name_constraints(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        excluded = [x509.DNSName(u"name.local")]
        nc = x509.NameConstraints(
            permitted_subtrees=None, excluded_subtrees=excluded
        )

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            nc, critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(
            ExtensionOID.NAME_CONSTRAINTS
        )
        assert ext.value == nc

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_key_usage(self, backend):
        issuer_private_key = RSA_KEY_2048.private_key(backend)
        subject_private_key = RSA_KEY_2048.private_key(backend)

        not_valid_before = datetime.datetime(2002, 1, 1, 12, 1)
        not_valid_after = datetime.datetime(2030, 12, 31, 8, 30)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(NameOID.COUNTRY_NAME, u'US')])
        ).not_valid_before(
            not_valid_before
        ).not_valid_after(
            not_valid_after
        ).public_key(
            subject_private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            x509.KeyUsage(
                digital_signature=True,
                content_commitment=True,
                key_encipherment=False,
                data_encipherment=False,
                key_agreement=False,
                key_cert_sign=True,
                crl_sign=False,
                encipher_only=False,
                decipher_only=False
            ),
            critical=False
        ).sign(issuer_private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(ExtensionOID.KEY_USAGE)
        assert ext.critical is False
        assert ext.value == x509.KeyUsage(
            digital_signature=True,
            content_commitment=True,
            key_encipherment=False,
            data_encipherment=False,
            key_agreement=False,
            key_cert_sign=True,
            crl_sign=False,
            encipher_only=False,
            decipher_only=False
        )

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_build_ca_request_with_path_length_none(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        request = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([
                x509.NameAttribute(NameOID.ORGANIZATION_NAME,
                                   u'PyCA'),
            ])
        ).add_extension(
            x509.BasicConstraints(ca=True, path_length=None), critical=True
        ).sign(private_key, hashes.SHA1(), backend)

        loaded_request = x509.load_pem_x509_csr(
            request.public_bytes(encoding=serialization.Encoding.PEM), backend
        )
        subject = loaded_request.subject
        assert isinstance(subject, x509.Name)
        basic_constraints = request.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.path_length is None

    @pytest.mark.parametrize(
        "unrecognized", [
            x509.UnrecognizedExtension(
                x509.ObjectIdentifier("1.2.3.4.5"),
                b"abcdef",
            )
        ]
    )
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    @pytest.mark.requires_backend_interface(interface=X509Backend)
    def test_unrecognized_extension(self, backend, unrecognized):
        private_key = RSA_KEY_2048.private_key(backend)

        cert = x509.CertificateBuilder().subject_name(
            x509.Name([x509.NameAttribute(x509.OID_COUNTRY_NAME, u'US')])
        ).issuer_name(
            x509.Name([x509.NameAttribute(x509.OID_COUNTRY_NAME, u'US')])
        ).not_valid_before(
            datetime.datetime(2002, 1, 1, 12, 1)
        ).not_valid_after(
            datetime.datetime(2030, 12, 31, 8, 30)
        ).public_key(
            private_key.public_key()
        ).serial_number(
            123
        ).add_extension(
            unrecognized, critical=False
        ).sign(private_key, hashes.SHA256(), backend)

        ext = cert.extensions.get_extension_for_oid(unrecognized.oid)

        assert ext.value == unrecognized


@pytest.mark.requires_backend_interface(interface=X509Backend)
class TestCertificateSigningRequestBuilder(object):
    @pytest.mark.requires_backend_interface(interface=RSABackend)
    def test_sign_invalid_hash_algorithm(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        builder = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([])
        )
        with pytest.raises(TypeError):
            builder.sign(private_key, 'NotAHash', backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    def test_no_subject_name(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        builder = x509.CertificateSigningRequestBuilder()
        with pytest.raises(ValueError):
            builder.sign(private_key, hashes.SHA256(), backend)

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    def test_build_ca_request_with_rsa(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        request = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([
                x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
            ])
        ).add_extension(
            x509.BasicConstraints(ca=True, path_length=2), critical=True
        ).sign(private_key, hashes.SHA1(), backend)

        assert isinstance(request.signature_hash_algorithm, hashes.SHA1)
        public_key = request.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        subject = request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA'),
        ]
        basic_constraints = request.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.ca is True
        assert basic_constraints.value.path_length == 2

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    def test_build_ca_request_with_unicode(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        request = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([
                x509.NameAttribute(NameOID.ORGANIZATION_NAME,
                                   u'PyCA\U0001f37a'),
            ])
        ).add_extension(
            x509.BasicConstraints(ca=True, path_length=2), critical=True
        ).sign(private_key, hashes.SHA1(), backend)

        loaded_request = x509.load_pem_x509_csr(
            request.public_bytes(encoding=serialization.Encoding.PEM), backend
        )
        subject = loaded_request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.ORGANIZATION_NAME, u'PyCA\U0001f37a'),
        ]

    @pytest.mark.requires_backend_interface(interface=RSABackend)
    def test_build_nonca_request_with_rsa(self, backend):
        private_key = RSA_KEY_2048.private_key(backend)

        request = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([
                x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
            ])
        ).add_extension(
            x509.BasicConstraints(ca=False, path_length=None), critical=True,
        ).sign(private_key, hashes.SHA1(), backend)

        assert isinstance(request.signature_hash_algorithm, hashes.SHA1)
        public_key = request.public_key()
        assert isinstance(public_key, rsa.RSAPublicKey)
        subject = request.subject
        assert isinstance(subject, x509.Name)
        assert list(subject) == [
            x509.NameAttribute(NameOID.COUNTRY_NAME, u'US'),
        ]
        basic_constraints = request.extensions.get_extension_for_oid(
            ExtensionOID.BASIC_CONSTRAINTS
        )
        assert basic_constraints.value.ca is False
        assert basic_constraints.value.path_length is None

    @pytest.mark.requires_backend_interface(interface=EllipticCurveBackend)
    def test_build_ca_request_with_ec(self, backend):
        if backend._lib.OPENSSL_VERSION_NUMBER < 0x10001000:
            pytest.skip("Requires a newer OpenSSL. Must be >= 1.0.1")

        _skip_curve_unsupported(backend, ec.SECP256R1())
        private_key = ec.generate_private_key(ec.SECP256R1(), backend)

        request = x509.CertificateSigningRequestBuilder().subject_name(
            x509.Name([
                x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, u'Texas'),