3 files changed, 33 insertions, 2 deletions
diff --git a/src/cryptography/hazmat/backends/openssl/x509.py b/src/cryptography/hazmat/backends/openssl/x509.py
index 2650b5d4..1376ab72 100644
--- a/src/cryptography/hazmat/backends/openssl/x509.py
+++ b/src/cryptography/hazmat/backends/openssl/x509.py
@@ -717,7 +717,9 @@ def _decode_invalidity_date(backend, inv_date):
             backend._ffi.cast("ASN1_STRING *", generalized_time)
         )
     ).decode("ascii")
-    return datetime.datetime.strptime(time, "%Y%m%d%H%M%SZ")
+    return x509.InvalidityDate(
+        datetime.datetime.strptime(time, "%Y%m%d%H%M%SZ")
+    )
 
 
 def _decode_cert_issuer(backend, ext):
diff --git a/src/cryptography/x509/__init__.py b/src/cryptography/x509/__init__.py
index 89e7f063..dc19161e 100644
--- a/src/cryptography/x509/__init__.py
+++ b/src/cryptography/x509/__init__.py
@@ -18,7 +18,7 @@ from cryptography.x509.extensions import (
     CRLNumber, CRLReason, CertificateIssuer, CertificatePolicies,
     DistributionPoint, DuplicateExtension, ExtendedKeyUsage, Extension,
     ExtensionNotFound, ExtensionType, Extensions, GeneralNames,
-    InhibitAnyPolicy, IssuerAlternativeName, KeyUsage,
+    InhibitAnyPolicy, InvalidityDate, IssuerAlternativeName, KeyUsage,
     NameConstraints, NoticeReference, OCSPNoCheck, PolicyInformation,
     ReasonFlags, SubjectAlternativeName, SubjectKeyIdentifier,
     UnsupportedExtension, UserNotice
@@ -168,4 +168,5 @@ __all__ = [
     "CRLExtensionOID",
     "CertificateIssuer",
     "CRLReason",
+    "InvalidityDate",
 ]
diff --git a/src/cryptography/x509/extensions.py b/src/cryptography/x509/extensions.py
index 6ae00927..22cba682 100644
--- a/src/cryptography/x509/extensions.py
+++ b/src/cryptography/x509/extensions.py
@@ -5,6 +5,7 @@
 from __future__ import absolute_import, division, print_function
 
 import abc
+import datetime
 import hashlib
 import ipaddress
 from enum import Enum
@@ -1001,3 +1002,30 @@ class CRLReason(object):
         return not self == other
 
     reason = utils.read_only_property("_reason")
+
+
+@utils.register_interface(ExtensionType)
+class InvalidityDate(object):
+    oid = CRLEntryExtensionOID.INVALIDITY_DATE
+
+    def __init__(self, invalidity_date):
+        if not isinstance(invalidity_date, datetime.datetime):
+            raise TypeError("invalidity_date must be a datetime.datetime")
+
+        self._invalidity_date = invalidity_date
+
+    def __repr__(self):
+        return "<InvalidityDate(invalidity_date={0})>".format(
+            self._invalidity_date
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, InvalidityDate):
+            return NotImplemented
+
+        return self.invalidity_date == other.invalidity_date
+
+    def __ne__(self, other):
+        return not self == other
+
+    invalidity_date = utils.read_only_property("_invalidity_date")