.. currentmodule:: cryptography.x509
.. testsetup::
pem_req_data = b"""
-----BEGIN CERTIFICATE REQUEST-----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-----END CERTIFICATE REQUEST-----
""".strip()
pem_data = b"""
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
""".strip()
cryptography_cert_pem = b"""
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
""".strip()
X.509 is an ITU-T standard for a public key infrastructure. X.509v3 is defined in RFC 5280 (which obsoletes RFC 2459 and RFC 3280). X.509 certificates are commonly used in protocols like TLS.
.. function:: load_pem_x509_certificate(data, backend)
.. versionadded:: 0.7
Deserialize a certificate from PEM encoded data. PEM certificates are
base64 decoded and have delimiters that look like
``-----BEGIN CERTIFICATE-----``.
:param bytes data: The PEM encoded certificate data.
:param backend: A backend supporting the
:class:`~cryptography.hazmat.backends.interfaces.X509Backend`
interface.
:returns: An instance of :class:`~cryptography.x509.Certificate`.
.. function:: load_der_x509_certificate(data, backend)
.. versionadded:: 0.7
Deserialize a certificate from DER encoded data. DER is a binary format
and is commonly found in files with the ``.cer`` extension (although file
extensions are not a guarantee of encoding type).
:param bytes data: The DER encoded certificate data.
:param backend: A backend supporting the
:class:`~cryptography.hazmat.backends.interfaces.X509Backend`
interface.
:returns: An instance of :class:`~cryptography.x509.Certificate`.
>>> from cryptography import x509
>>> from cryptography.hazmat.backends import default_backend
>>> cert = x509.load_pem_x509_certificate(pem_data, default_backend())
>>> cert.serial
2.. function:: load_pem_x509_csr(data, backend)
.. versionadded:: 0.9
Deserialize a certificate signing request (CSR) from PEM encoded data. PEM
requests are base64 decoded and have delimiters that look like
``-----BEGIN CERTIFICATE REQUEST-----``. This format is also known as
PKCS#10.
:param bytes data: The PEM encoded request data.
:param backend: A backend supporting the
:class:`~cryptography.hazmat.backends.interfaces.X509Backend`
interface.
:returns: An instance of
:class:`~cryptography.x509.CertificateSigningRequest`.
.. function:: load_der_x509_csr(data, backend)
.. versionadded:: 0.9
Deserialize a certificate signing request (CSR) from DER encoded data. DER
is a binary format and is not commonly used with CSRs.
:param bytes data: The DER encoded request data.
:param backend: A backend supporting the
:class:`~cryptography.hazmat.backends.interfaces.X509Backend`
interface.
:returns: An instance of
:class:`~cryptography.x509.CertificateSigningRequest`.
>>> from cryptography import x509
>>> from cryptography.hazmat.backends import default_backend
>>> from cryptography.hazmat.primitives import hashes
>>> csr = x509.load_pem_x509_csr(pem_req_data, default_backend())
>>> isinstance(csr.signature_hash_algorithm, hashes.SHA1)
True.. versionadded:: 0.7
.. attribute:: version
:type: :class:`~cryptography.x509.Version`
The certificate version as an enumeration. Version 3 certificates are
the latest version and also the only type you should see in practice.
:raises cryptography.x509.InvalidVersion: If the version in the
certificate is not a known
:class:`X.509 version <cryptography.x509.Version>`.
.. doctest::
>>> cert.version
<Version.v3: 2>
.. method:: fingerprint(algorithm)
:param algorithm: The
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
that will be used to generate the fingerprint.
:return bytes: The fingerprint using the supplied hash algorithm, as
bytes.
.. doctest::
>>> from cryptography.hazmat.primitives import hashes
>>> cert.fingerprint(hashes.SHA256())
'\x86\xd2\x187Gc\xfc\xe7}[+E9\x8d\xb4\x8f\x10\xe5S\xda\x18u\xbe}a\x03\x08[\xac\xa04?'
.. attribute:: serial
:type: int
The serial as a Python integer.
.. doctest::
>>> cert.serial
2
.. method:: public_key()
:type:
:class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey` or
:class:`~cryptography.hazmat.primitives.asymmetric.dsa.DSAPublicKey` or
:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicKey`
The public key associated with the certificate.
.. doctest::
>>> from cryptography.hazmat.primitives.asymmetric import rsa
>>> public_key = cert.public_key()
>>> isinstance(public_key, rsa.RSAPublicKey)
True
.. attribute:: not_valid_before
:type: :class:`datetime.datetime`
A naïve datetime representing the beginning of the validity period for
the certificate in UTC. This value is inclusive.
.. doctest::
>>> cert.not_valid_before
datetime.datetime(2010, 1, 1, 8, 30)
.. attribute:: not_valid_after
:type: :class:`datetime.datetime`
A naïve datetime representing the end of the validity period for the
certificate in UTC. This value is inclusive.
.. doctest::
>>> cert.not_valid_after
datetime.datetime(2030, 12, 31, 8, 30)
.. attribute:: issuer
.. versionadded:: 0.8
:type: :class:`Name`
The :class:`Name` of the issuer.
.. attribute:: subject
.. versionadded:: 0.8
:type: :class:`Name`
The :class:`Name` of the subject.
.. attribute:: signature_hash_algorithm
:type: :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
Returns the
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm` which
was used in signing this certificate.
.. doctest::
>>> from cryptography.hazmat.primitives import hashes
>>> isinstance(cert.signature_hash_algorithm, hashes.SHA256)
True
.. attribute:: extensions
:type: :class:`Extensions`
The extensions encoded in the certificate.
:raises cryptography.x509.DuplicateExtension: If more than one
extension of the same type is found within the certificate.
:raises cryptography.x509.UnsupportedExtension: If the certificate
contains an extension that is not supported.
:raises cryptography.x509.UnsupportedGeneralNameType: If an extension
contains a general name that is not supported.
:raises UnicodeError: If an extension contains IDNA encoding that is
invalid or not compliant with IDNA 2008.
.. doctest::
>>> for ext in cert.extensions:
... print(ext)
<Extension(oid=<ObjectIdentifier(oid=2.5.29.35, name=authorityKeyIdentifier)>, critical=False, value=<AuthorityKeyIdentifier(key_identifier='\xe4}_\xd1\\\x95\x86\x08,\x05\xae\xbeu\xb6e\xa7\xd9]\xa8f', authority_cert_issuer=None, authority_cert_serial_number=None)>)>
<Extension(oid=<ObjectIdentifier(oid=2.5.29.14, name=subjectKeyIdentifier)>, critical=False, value=<SubjectKeyIdentifier(digest='X\x01\x84$\x1b\xbc+R\x94J=\xa5\x10r\x14Q\xf5\xaf:\xc9')>)>
<Extension(oid=<ObjectIdentifier(oid=2.5.29.15, name=keyUsage)>, critical=True, value=<KeyUsage(digital_signature=False, content_commitment=False, key_encipherment=False, data_encipherment=False, key_agreement=False, key_cert_sign=True, crl_sign=True, encipher_only=None, decipher_only=None)>)>
<Extension(oid=<ObjectIdentifier(oid=2.5.29.32, name=certificatePolicies)>, critical=False, value=<CertificatePolicies([<PolicyInformation(policy_identifier=<ObjectIdentifier(oid=2.16.840.1.101.3.2.1.48.1, name=Unknown OID)>, policy_qualifiers=None)>])>)>
<Extension(oid=<ObjectIdentifier(oid=2.5.29.19, name=basicConstraints)>, critical=True, value=<BasicConstraints(ca=True, path_length=None)>)>
.. method:: public_bytes(encoding)
:param encoding: The
:class:`~cryptography.hazmat.primitives.serialization.Encoding`
that will be used to serialize the certificate.
:return bytes: The data that can be written to a file or sent
over the network to be verified by clients.
.. versionadded:: 1.0
.. method:: fingerprint(algorithm)
:param algorithm: The
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
that will be used to generate the fingerprint.
:return bytes: The fingerprint using the supplied hash algorithm, as
bytes.
.. attribute:: signature_hash_algorithm
:type: :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
Returns the
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm` which
was used in signing this CRL.
.. attribute:: issuer
:type: :class:`Name`
The :class:`Name` of the issuer.
.. attribute:: next_update
:type: :class:`datetime.datetime`
A naïve datetime representing when the next update to this CRL is
expected.
.. attribute:: last_update
:type: :class:`datetime.datetime`
A naïve datetime representing when the this CRL was last updated.
.. attribute:: revoked_certificates
:type: list of :class:`RevokedCertificate`
The revoked certificates listed in this CRL.
.. attribute:: extensions
:type: :class:`Extensions`
The extensions encoded in the CRL.
.. versionadded:: 0.9
.. method:: public_key()
:type:
:class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey` or
:class:`~cryptography.hazmat.primitives.asymmetric.dsa.DSAPublicKey` or
:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePublicKey`
The public key associated with the request.
.. doctest::
>>> from cryptography.hazmat.primitives.asymmetric import rsa
>>> public_key = csr.public_key()
>>> isinstance(public_key, rsa.RSAPublicKey)
True
.. attribute:: subject
:type: :class:`Name`
The :class:`Name` of the subject.
.. attribute:: signature_hash_algorithm
:type: :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
Returns the
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm` which
was used in signing this request.
.. doctest::
>>> from cryptography.hazmat.primitives import hashes
>>> isinstance(csr.signature_hash_algorithm, hashes.SHA1)
True
.. method:: public_bytes(encoding)
:param encoding: The
:class:`~cryptography.hazmat.primitives.serialization.Encoding`
that will be used to serialize the certificate request.
:return bytes: The data that can be written to a file or sent
over the network to be signed by the certificate
authority.
.. versionadded:: 1.0
.. attribute:: serial_number
:type: :class:`int`
An integer representing the serial number of the revoked certificate.
.. attribute:: revocation_date
:type: :class:`datetime.datetime`
A naïve datetime representing the date this certificates was revoked.
.. attribute:: extensions
:type: :class:`Extensions`
The extensions encoded in the revoked certificate.
.. versionadded:: 1.0
>>> from cryptography import x509
>>> from cryptography.hazmat.backends import default_backend
>>> from cryptography.hazmat.primitives import hashes
>>> from cryptography.hazmat.primitives.asymmetric import rsa
>>> private_key = rsa.generate_private_key(
... public_exponent=65537,
... key_size=2048,
... backend=default_backend()
... )
>>> builder = x509.CertificateSigningRequestBuilder()
>>> builder = builder.subject_name(x509.Name([
... x509.NameAttribute(x509.OID_COMMON_NAME, u'cryptography.io'),
... ]))
>>> builder = builder.add_extension(
... x509.BasicConstraints(ca=False, path_length=None), critical=True,
... )
>>> request = builder.sign(
... private_key, hashes.SHA256(), default_backend()
... )
>>> isinstance(request, x509.CertificateSigningRequest)
True.. method:: subject_name(name)
:param name: The :class:`~cryptography.x509.Name` of the certificate
subject.
:returns: A new
:class:`~cryptography.x509.CertificateSigningRequestBuilder`.
.. method:: add_extension(extension, critical)
:param extension: The :class:`~cryptography.x509.Extension` to add to
the request.
:param critical: Set to `True` if the extension must be understood and
handled by whoever reads the certificate.
:returns: A new
:class:`~cryptography.x509.CertificateSigningRequestBuilder`.
.. method:: sign(private_key, algorithm, backend)
:param backend: Backend that will be used to sign the request.
Must support the
:class:`~cryptography.hazmat.backends.interfaces.X509Backend`
interface.
:param private_key: The
:class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey`,
:class:`~cryptography.hazmat.primitives.asymmetric.dsa.DSAPrivateKey` or
:class:`~cryptography.hazmat.primitives.asymmetric.ec.EllipticCurvePrivateKey`
that will be used to sign the request. When the request is
signed by a certificate authority, the private key's associated
public key will be stored in the resulting certificate.
:param algorithm: The
:class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
that will be used to generate the request signature.
:returns: A new
:class:`~cryptography.x509.CertificateSigningRequest`.
.. versionadded:: 0.8
An X509 Name is an ordered list of attributes. The object is iterable to
get every attribute or you can use :meth:`Name.get_attributes_for_oid` to
obtain the specific type you want. Names are sometimes represented as a
slash or comma delimited string (e.g. /CN=mydomain.com/O=My Org/C=US or
CN=mydomain.com, O=My Org, C=US).
>>> len(cert.subject)
3
>>> for attribute in cert.subject:
... print(attribute)
<NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.6, name=countryName)>, value=u'US')>
<NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.10, name=organizationName)>, value=u'Test Certificates 2011')>
<NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.3, name=commonName)>, value=u'Good CA')>.. method:: get_attributes_for_oid(oid)
:param oid: An :class:`ObjectIdentifier` instance.
:returns: A list of :class:`NameAttribute` instances that match the
OID provided. If nothing matches an empty list will be returned.
.. doctest::
>>> cert.subject.get_attributes_for_oid(x509.OID_COMMON_NAME)
[<NameAttribute(oid=<ObjectIdentifier(oid=2.5.4.3, name=commonName)>, value=u'Good CA')>]
.. versionadded:: 0.7
An enumeration for X.509 versions.
.. attribute:: v1
For version 1 X.509 certificates.
.. attribute:: v3
For version 3 X.509 certificates.
.. versionadded:: 0.8
An X.509 name consists of a list of NameAttribute instances.
.. attribute:: oid
:type: :class:`ObjectIdentifier`
The attribute OID.
.. attribute:: value
:type: :term:`text`
The value of the attribute.
.. versionadded:: 0.8
Object identifiers (frequently seen abbreviated as OID) identify the type of a value (see: :class:`NameAttribute`).
.. attribute:: dotted_string
:type: :class:`str`
The dotted string value of the OID (e.g. ``"2.5.4.3"``)
.. versionadded:: 0.9
This is the generic interface that all the following classes are registered against.
.. versionadded:: 0.9
This corresponds to an email address. For example, user@example.com.
.. attribute:: value
:type: :term:`text`
.. versionadded:: 0.9
This corresponds to a domain name. For example, cryptography.io.
.. attribute:: value
:type: :term:`text`
.. versionadded:: 0.9
This corresponds to a directory name.
.. attribute:: value
:type: :class:`Name`
.. versionadded:: 0.9
This corresponds to a uniform resource identifier. For example,
https://cryptography.io. The URI is parsed and IDNA decoded (see
RFC 5895).
Note
URIs that do not contain :// in them will not be decoded.
.. attribute:: value
:type: :term:`text`
.. versionadded:: 0.9
This corresponds to an IP address.
.. attribute:: value
:type: :class:`~ipaddress.IPv4Address`,
:class:`~ipaddress.IPv6Address`, :class:`~ipaddress.IPv4Network`,
or :class:`~ipaddress.IPv6Network`.
.. versionadded:: 0.9
This corresponds to a registered ID.
.. attribute:: value
:type: :class:`ObjectIdentifier`
.. versionadded:: 1.0
This corresponds to an otherName. An otherName has a type identifier and a value represented in binary DER format.
.. attribute:: type_id
:type: :class:`ObjectIdentifier`
.. attribute:: value
:type: `bytes`
.. versionadded:: 0.9
An X.509 Extensions instance is an ordered list of extensions. The object is iterable to get every extension.
.. method:: get_extension_for_oid(oid)
:param oid: An :class:`ObjectIdentifier` instance.
:returns: An instance of the extension class.
:raises cryptography.x509.ExtensionNotFound: If the certificate does
not have the extension requested.
.. doctest::
>>> cert.extensions.get_extension_for_oid(x509.OID_BASIC_CONSTRAINTS)
<Extension(oid=<ObjectIdentifier(oid=2.5.29.19, name=basicConstraints)>, critical=True, value=<BasicConstraints(ca=True, path_length=None)>)>
.. versionadded:: 0.9
.. attribute:: oid
:type: :class:`ObjectIdentifier`
The :ref:`extension OID <extension_oids>`.
.. attribute:: critical
:type: bool
Determines whether a given extension is critical or not. :rfc:`5280`
requires that "A certificate-using system MUST reject the certificate
if it encounters a critical extension it does not recognize or a
critical extension that contains information that it cannot process".
.. attribute:: value
Returns an instance of the extension type corresponding to the OID.
.. versionadded:: 0.9
The key usage extension defines the purpose of the key contained in the certificate. The usage restriction might be employed when a key that could be used for more than one operation is to be restricted. It corresponds to :data:`OID_KEY_USAGE`.
.. attribute:: digital_signature
:type: bool
This purpose is set to true when the subject public key is used for verifying
digital signatures, other than signatures on certificates
(``key_cert_sign``) and CRLs (``crl_sign``).
.. attribute:: content_commitment
:type: bool
This purpose is set to true when the subject public key is used for verifying
digital signatures, other than signatures on certificates
(``key_cert_sign``) and CRLs (``crl_sign``). It is used to provide a
non-repudiation service that protects against the signing entity
falsely denying some action. In the case of later conflict, a
reliable third party may determine the authenticity of the signed
data. This was called ``non_repudiation`` in older revisions of the
X.509 specification.
.. attribute:: key_encipherment
:type: bool
This purpose is set to true when the subject public key is used for
enciphering private or secret keys.
.. attribute:: data_encipherment
:type: bool
This purpose is set to true when the subject public key is used for
directly enciphering raw user data without the use of an intermediate
symmetric cipher.
.. attribute:: key_agreement
:type: bool
This purpose is set to true when the subject public key is used for key
agreement. For example, when a Diffie-Hellman key is to be used for
key management, then this purpose is set to true.
.. attribute:: key_cert_sign
:type: bool
This purpose is set to true when the subject public key is used for
verifying signatures on public key certificates. If this purpose is set
to true then ``ca`` must be true in the :class:`BasicConstraints`
extension.
.. attribute:: crl_sign
:type: bool
This purpose is set to true when the subject public key is used for
verifying signatures on certificate revocation lists.
.. attribute:: encipher_only
:type: bool
When this purposes is set to true and the ``key_agreement`` purpose is
also set, the subject public key may be used only for enciphering data
while performing key agreement.
:raises ValueError: This is raised if accessed when ``key_agreement``
is false.
.. attribute:: decipher_only
:type: bool
When this purposes is set to true and the ``key_agreement`` purpose is
also set, the subject public key may be used only for deciphering data
while performing key agreement.
:raises ValueError: This is raised if accessed when ``key_agreement``
is false.
.. versionadded:: 0.9
Basic constraints is an X.509 extension type that defines whether a given certificate is allowed to sign additional certificates and what path length restrictions may exist. It corresponds to :data:`OID_BASIC_CONSTRAINTS`.
.. attribute:: ca
:type: bool
Whether the certificate can sign certificates.
.. attribute:: path_length
:type: int or None
The maximum path length for certificates subordinate to this
certificate. This attribute only has meaning if ``ca`` is true.
If ``ca`` is true then a path length of None means there's no
restriction on the number of subordinate CAs in the certificate chain.
If it is zero or greater then it defines the maximum length for a
subordinate CA's certificate chain. For example, a ``path_length`` of 1
means the certificate can sign a subordinate CA, but the subordinate CA
is not allowed to create subordinates with ``ca`` set to true.
.. versionadded:: 0.9
This extension indicates one or more purposes for which the certified public key may be used, in addition to or in place of the basic purposes indicated in the key usage extension. The object is iterable to obtain the list of :ref:`extended key usage OIDs <eku_oids>`.
.. versionadded:: 1.0
This presence of this extension indicates that an OCSP client can trust a responder for the lifetime of the responder's certificate. CAs issuing such a certificate should realize that a compromise of the responder's key is as serious as the compromise of a CA key used to sign CRLs, at least for the validity period of this certificate. CA's may choose to issue this type of certificate with a very short lifetime and renew it frequently. This extension is only relevant when the certificate is an authorized OCSP responder.
.. versionadded:: 1.0
The name constraints extension, which only has meaning in a CA certificate, defines a name space within which all subject names in certificates issued beneath the CA certificate must (or must not) be in. For specific details on the way this extension should be processed see RFC 5280.
.. attribute:: permitted_subtrees
:type: list of :class:`GeneralName` objects or None
The set of permitted name patterns. If a name matches this and an
element in ``excluded_subtrees`` it is invalid. At least one of
``permitted_subtrees`` and ``excluded_subtrees`` will be non-None.
.. attribute:: excluded_subtrees
:type: list of :class:`GeneralName` objects or None
Any name matching a restriction in the ``excluded_subtrees`` field is
invalid regardless of information appearing in the
``permitted_subtrees``. At least one of ``permitted_subtrees`` and
``excluded_subtrees`` will be non-None.
.. versionadded:: 0.9
The authority key identifier extension provides a means of identifying the public key corresponding to the private key used to sign a certificate. This extension is typically used to assist in determining the appropriate certificate chain. For more information about generation and use of this extension see RFC 5280 section 4.2.1.1.
.. attribute:: key_identifier
:type: bytes
A value derived from the public key used to verify the certificate's
signature.
.. attribute:: authority_cert_issuer
:type: :class:`Name` or None
The :class:`Name` of the issuer's issuer.
.. attribute:: authority_cert_serial_number
:type: int or None
The serial number of the issuer's issuer.
.. versionadded:: 0.9
The subject key identifier extension provides a means of identifying certificates that contain a particular public key.
.. attribute:: digest
:type: bytes
The binary value of the identifier.
.. versionadded:: 0.9
Subject alternative name is an X.509 extension that provides a list of :ref:`general name <general_name_classes>` instances that provide a set of identities for which the certificate is valid. The object is iterable to get every element.
.. method:: get_values_for_type(type)
:param type: A :class:`GeneralName` provider. This is one of the
:ref:`general name classes <general_name_classes>`.
:returns: A list of values extracted from the matched general names.
The type of the returned values depends on the :class:`GeneralName`.
.. doctest::
>>> from cryptography import x509
>>> from cryptography.hazmat.backends import default_backend
>>> from cryptography.hazmat.primitives import hashes
>>> cert = x509.load_pem_x509_certificate(cryptography_cert_pem, default_backend())
>>> # Get the subjectAltName extension from the certificate
>>> ext = cert.extensions.get_extension_for_oid(x509.OID_SUBJECT_ALTERNATIVE_NAME)
>>> # Get the dNSName entries from the SAN extension
>>> ext.value.get_values_for_type(x509.DNSName)
[u'www.cryptography.io', u'cryptography.io']
.. versionadded:: 1.0
Issuer alternative name is an X.509 extension that provides a list of :ref:`general name <general_name_classes>` instances that provide a set of identities for the certificate issuer. The object is iterable to get every element.
.. method:: get_values_for_type(type)
:param type: A :class:`GeneralName` provider. This is one of the
:ref:`general name classes <general_name_classes>`.
:returns: A list of values extracted from the matched general names.
.. versionadded:: 0.9
The authority information access extension indicates how to access information and services for the issuer of the certificate in which the extension appears. Information and services may include online validation services (such as OCSP) and issuer data. It is an iterable, containing one or more :class:`AccessDescription` instances.
.. versionadded:: 0.9
.. attribute:: access_method
:type: :class:`ObjectIdentifier`
The access method defines what the ``access_location`` means. It must
be either :data:`OID_OCSP` or :data:`OID_CA_ISSUERS`. If it is
:data:`OID_OCSP` the access location will be where to obtain OCSP
information for the certificate. If it is :data:`OID_CA_ISSUERS` the
access location will provide additional information about the issuing
certificate.
.. attribute:: access_location
:type: :class:`GeneralName`
Where to access the information defined by the access method.
.. versionadded:: 0.9
The CRL distribution points extension identifies how CRL information is obtained. It is an iterable, containing one or more :class:`DistributionPoint` instances.
.. versionadded:: 0.9
.. attribute:: full_name
:type: list of :class:`GeneralName` instances or None
This field describes methods to retrieve the CRL. At most one of
``full_name`` or ``relative_name`` will be non-None.
.. attribute:: relative_name
:type: :class:`Name` or None
This field describes methods to retrieve the CRL relative to the CRL
issuer. At most one of ``full_name`` or ``relative_name`` will be
non-None.
.. attribute:: crl_issuer
:type: list of :class:`GeneralName` instances or None
Information about the issuer of the CRL.
.. attribute:: reasons
:type: frozenset of :class:`ReasonFlags` or None
The reasons a given distribution point may be used for when performing
revocation checks.
.. versionadded:: 0.9
An enumeration for CRL reasons.
.. attribute:: unspecified
It is unspecified why the certificate was revoked. This reason cannot
be used as a reason flag in a :class:`DistributionPoint`.
.. attribute:: key_compromise
This reason indicates that the private key was compromised.
.. attribute:: ca_compromise
This reason indicates that the CA issuing the certificate was
compromised.
.. attribute:: affiliation_changed
This reason indicates that the subject's name or other information has
changed.
.. attribute:: superseded
This reason indicates that a certificate has been superseded.
.. attribute:: cessation_of_operation
This reason indicates that the certificate is no longer required.
.. attribute:: certificate_hold
This reason indicates that the certificate is on hold.
.. attribute:: privilege_withdrawn
This reason indicates that the privilege granted by this certificate
have been withdrawn.
.. attribute:: aa_compromise
When an attribute authority has been compromised.
.. attribute:: remove_from_crl
This reason indicates that the certificate was on hold and should be
removed from the CRL. This reason cannot be used as a reason flag
in a :class:`DistributionPoint`.
.. versionadded:: 1.0
The inhibit anyPolicy extension indicates that the special OID
:data:`OID_ANY_POLICY`, is not considered an explicit match for other
:class:`CertificatePolicies` except when it appears in an intermediate
self-issued CA certificate. The value indicates the number of additional
non-self-issued certificates that may appear in the path before
:data:`OID_ANY_POLICY` is no longer permitted. For example, a value
of one indicates that :data:`OID_ANY_POLICY` may be processed in
certificates issued by the subject of this certificate, but not in
additional certificates in the path.
.. attribute:: skip_certs
:type: int
.. versionadded:: 0.9
The certificate policies extension is an iterable, containing one or more :class:`PolicyInformation` instances.
These classes may be present within a :class:`CertificatePolicies` instance.
.. versionadded:: 0.9
Contains a policy identifier and an optional list of qualifiers.
.. attribute:: policy_identifier
:type: :class:`ObjectIdentifier`
.. attribute:: policy_qualifiers
:type: list
A list consisting of :term:`text` and/or :class:`UserNotice` objects.
If the value is text it is a pointer to the practice statement
published by the certificate authority. If it is a user notice it is
meant for display to the relying party when the certificate is
used.
.. versionadded:: 0.9
User notices are intended for display to a relying party when a certificate is used. In practice, few if any UIs expose this data and it is a rarely encoded component.
.. attribute:: notice_reference
:type: :class:`NoticeReference` or None
The notice reference field names an organization and identifies,
by number, a particular statement prepared by that organization.
.. attribute:: explicit_text
This field includes an arbitrary textual statement directly in the
certificate.
:type: :term:`text`
Notice reference can name an organization and provide information about notices related to the certificate. For example, it might identify the organization name and notice number 1. Application software could have a notice file containing the current set of notices for the named organization; the application would then extract the notice text from the file and display it. In practice this is rarely seen.
.. versionadded:: 0.9
.. attribute:: organization
:type: :term:`text`
.. attribute:: notice_numbers
:type: list
A list of integers.
X.509 elements are frequently identified by :class:`ObjectIdentifier` instances. The following common OIDs are available as constants.
.. data:: OID_COMMON_NAME
Corresponds to the dotted string ``"2.5.4.3"``. Historically the domain
name would be encoded here for server certificates. :rfc:`2818` deprecates
this practice and names of that type should now be located in a
SubjectAlternativeName extension. This OID is typically seen in X.509 names.
.. data:: OID_COUNTRY_NAME
Corresponds to the dotted string ``"2.5.4.6"``. This OID is typically seen
in X.509 names.
.. data:: OID_LOCALITY_NAME
Corresponds to the dotted string ``"2.5.4.7"``. This OID is typically seen
in X.509 names.
.. data:: OID_STATE_OR_PROVINCE_NAME
Corresponds to the dotted string ``"2.5.4.8"``. This OID is typically seen
in X.509 names.
.. data:: OID_ORGANIZATION_NAME
Corresponds to the dotted string ``"2.5.4.10"``. This OID is typically seen
in X.509 names.
.. data:: OID_ORGANIZATIONAL_UNIT_NAME
Corresponds to the dotted string ``"2.5.4.11"``. This OID is typically seen
in X.509 names.
.. data:: OID_SERIAL_NUMBER
Corresponds to the dotted string ``"2.5.4.5"``. This is distinct from the
serial number of the certificate itself (which can be obtained with
:func:`Certificate.serial`). This OID is typically seen in X.509 names.
.. data:: OID_SURNAME
Corresponds to the dotted string ``"2.5.4.4"``. This OID is typically seen
in X.509 names.
.. data:: OID_GIVEN_NAME
Corresponds to the dotted string ``"2.5.4.42"``. This OID is typically seen
in X.509 names.
.. data:: OID_TITLE
Corresponds to the dotted string ``"2.5.4.12"``. This OID is typically seen
in X.509 names.
.. data:: OID_GENERATION_QUALIFIER
Corresponds to the dotted string ``"2.5.4.44"``. This OID is typically seen
in X.509 names.
.. data:: OID_DN_QUALIFIER
Corresponds to the dotted string ``"2.5.4.46"``. This specifies
disambiguating information to add to the relative distinguished name of an
entry. See :rfc:`2256`. This OID is typically seen in X.509 names.
.. data:: OID_PSEUDONYM
Corresponds to the dotted string ``"2.5.4.65"``. This OID is typically seen
in X.509 names.
.. data:: OID_DOMAIN_COMPONENT
Corresponds to the dotted string ``"0.9.2342.19200300.100.1.25"``. A string
holding one component of a domain name. See :rfc:`4519`. This OID is
typically seen in X.509 names.
.. data:: OID_EMAIL_ADDRESS
Corresponds to the dotted string ``"1.2.840.113549.1.9.1"``. This OID is
typically seen in X.509 names.
.. data:: OID_RSA_WITH_MD5
Corresponds to the dotted string ``"1.2.840.113549.1.1.4"``. This is
an MD5 digest signed by an RSA key.
.. data:: OID_RSA_WITH_SHA1
Corresponds to the dotted string ``"1.2.840.113549.1.1.5"``. This is
a SHA1 digest signed by an RSA key.
.. data:: OID_RSA_WITH_SHA224
Corresponds to the dotted string ``"1.2.840.113549.1.1.14"``. This is
a SHA224 digest signed by an RSA key.
.. data:: OID_RSA_WITH_SHA256
Corresponds to the dotted string ``"1.2.840.113549.1.1.11"``. This is
a SHA256 digest signed by an RSA key.
.. data:: OID_RSA_WITH_SHA384
Corresponds to the dotted string ``"1.2.840.113549.1.1.12"``. This is
a SHA384 digest signed by an RSA key.
.. data:: OID_RSA_WITH_SHA512
Corresponds to the dotted string ``"1.2.840.113549.1.1.13"``. This is
a SHA512 digest signed by an RSA key.
.. data:: OID_ECDSA_WITH_SHA1
Corresponds to the dotted string ``"1.2.840.10045.4.1"``. This is a SHA1
digest signed by an ECDSA key.
.. data:: OID_ECDSA_WITH_SHA224
Corresponds to the dotted string ``"1.2.840.10045.4.3.1"``. This is
a SHA224 digest signed by an ECDSA key.
.. data:: OID_ECDSA_WITH_SHA256
Corresponds to the dotted string ``"1.2.840.10045.4.3.2"``. This is
a SHA256 digest signed by an ECDSA key.
.. data:: OID_ECDSA_WITH_SHA384
Corresponds to the dotted string ``"1.2.840.10045.4.3.3"``. This is
a SHA384 digest signed by an ECDSA key.
.. data:: OID_ECDSA_WITH_SHA512
Corresponds to the dotted string ``"1.2.840.10045.4.3.4"``. This is
a SHA512 digest signed by an ECDSA key.
.. data:: OID_DSA_WITH_SHA1
Corresponds to the dotted string ``"1.2.840.10040.4.3"``. This is
a SHA1 digest signed by a DSA key.
.. data:: OID_DSA_WITH_SHA224
Corresponds to the dotted string ``"2.16.840.1.101.3.4.3.1"``. This is
a SHA224 digest signed by a DSA key.
.. data:: OID_DSA_WITH_SHA256
Corresponds to the dotted string ``"2.16.840.1.101.3.4.3.2"``. This is
a SHA256 digest signed by a DSA key.
.. data:: OID_SERVER_AUTH
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.1"``. This is used to
denote that a certificate may be used for TLS web server authentication.
.. data:: OID_CLIENT_AUTH
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.2"``. This is used to
denote that a certificate may be used for TLS web client authentication.
.. data:: OID_CODE_SIGNING
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.3"``. This is used to
denote that a certificate may be used for code signing.
.. data:: OID_EMAIL_PROTECTION
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.4"``. This is used to
denote that a certificate may be used for email protection.
.. data:: OID_TIME_STAMPING
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.8"``. This is used to
denote that a certificate may be used for time stamping.
.. data:: OID_OCSP_SIGNING
Corresponds to the dotted string ``"1.3.6.1.5.5.7.3.9"``. This is used to
denote that a certificate may be used for signing OCSP responses.
.. data:: OID_OCSP
Corresponds to the dotted string ``"1.3.6.1.5.5.7.48.1"``. Used as the
identifier for OCSP data in :class:`AccessDescription` objects.
.. data:: OID_CA_ISSUERS
Corresponds to the dotted string ``"1.3.6.1.5.5.7.48.2"``. Used as the
identifier for CA issuer data in :class:`AccessDescription` objects.
.. data:: OID_CPS_QUALIFIER
Corresponds to the dotted string ``"1.3.6.1.5.5.7.2.1"``.
.. data:: OID_CPS_USER_NOTICE
Corresponds to the dotted string ``"1.3.6.1.5.5.7.2.2"``.
.. data:: OID_ANY_POLICY
Corresponds to the dotted string ``"2.5.29.32.0"``.
.. data:: OID_BASIC_CONSTRAINTS
Corresponds to the dotted string ``"2.5.29.19"``. The identifier for the
:class:`BasicConstraints` extension type.
.. data:: OID_KEY_USAGE
Corresponds to the dotted string ``"2.5.29.15"``. The identifier for the
:class:`KeyUsage` extension type.
.. data:: OID_SUBJECT_ALTERNATIVE_NAME
Corresponds to the dotted string ``"2.5.29.17"``. The identifier for the
:class:`SubjectAlternativeName` extension type.
.. data:: OID_ISSUER_ALTERNATIVE_NAME
Corresponds to the dotted string ``"2.5.29.18"``. The identifier for the
:class:`IssuerAlternativeName` extension type.
.. data:: OID_SUBJECT_KEY_IDENTIFIER
Corresponds to the dotted string ``"2.5.29.14"``. The identifier for the
:class:`SubjectKeyIdentifier` extension type.
.. data:: OID_NAME_CONSTRAINTS
Corresponds to the dotted string ``"2.5.29.30"``. The identifier for the
:class:`NameConstraints` extension type.
.. data:: OID_CRL_DISTRIBUTION_POINTS
Corresponds to the dotted string ``"2.5.29.31"``. The identifier for the
:class:`CRLDistributionPoints` extension type.
.. data:: OID_CERTIFICATE_POLICIES
Corresponds to the dotted string ``"2.5.29.32"``. The identifier for the
:class:`CertificatePolicies` extension type.
.. data:: OID_AUTHORITY_KEY_IDENTIFIER
Corresponds to the dotted string ``"2.5.29.35"``. The identifier for the
:class:`AuthorityKeyIdentifier` extension type.
.. data:: OID_EXTENDED_KEY_USAGE
Corresponds to the dotted string ``"2.5.29.37"``. The identifier for the
:class:`ExtendedKeyUsage` extension type.
.. data:: OID_AUTHORITY_INFORMATION_ACCESS
Corresponds to the dotted string ``"1.3.6.1.5.5.7.1.1"``. The identifier
for the :class:`AuthorityInformationAccess` extension type.
.. data:: OID_OCSP_NO_CHECK
Corresponds to the dotted string ``"1.3.6.1.5.5.7.48.1.5"``. The identifier
for the :class:`OCSPNoCheck` extension type.
This is raised when an X.509 certificate has an invalid version number.
.. attribute:: parsed_version
:type: int
Returns the raw version that was parsed from the certificate.
This is raised when more than one X.509 extension of the same type is found within a certificate.
.. attribute:: oid
:type: :class:`ObjectIdentifier`
Returns the OID.
This is raised when a certificate contains an unsupported extension type.
.. attribute:: oid
:type: :class:`ObjectIdentifier`
Returns the OID.
This is raised when calling :meth:`Extensions.get_extension_for_oid` with an extension OID that is not present in the certificate.
.. attribute:: oid
:type: :class:`ObjectIdentifier`
Returns the OID.
This is raised when a certificate contains an unsupported general name type in an extension.
.. attribute:: type
:type: int
The integer value of the unsupported type. The complete list of
types can be found in `RFC 5280 section 4.2.1.6`_.