don't sort the serial numbers in a parsed CRL (#4457)
* don't sort the serial numbers in a parsed CRL
OpenSSL sorts them in place and this breaks the signature and more.
fixes #4456
* cache the sorted CRL (but create it lazily)
* use the cache decorator
diff --git a/src/cryptography/hazmat/backends/openssl/x509.py b/src/cryptography/hazmat/backends/openssl/x509.py
index a7a2c70..ad838b7 100644
--- a/src/cryptography/hazmat/backends/openssl/x509.py
+++ b/src/cryptography/hazmat/backends/openssl/x509.py
@@ -238,11 +238,21 @@
h.update(der)
return h.finalize()
+ @utils.cached_property
+ def _sorted_crl(self):
+ # X509_CRL_get0_by_serial sorts in place, which breaks a variety of
+ # things we don't want to break (like iteration and the signature).
+ # Let's dupe it and sort that instead.
+ dup = self._backend._lib.X509_CRL_dup(self._x509_crl)
+ self._backend.openssl_assert(dup != self._backend._ffi.NULL)
+ dup = self._backend._ffi.gc(dup, self._backend._lib.X509_CRL_free)
+ return dup
+
def get_revoked_certificate_by_serial_number(self, serial_number):
revoked = self._backend._ffi.new("X509_REVOKED **")
asn1_int = _encode_asn1_int_gc(self._backend, serial_number)
res = self._backend._lib.X509_CRL_get0_by_serial(
- self._x509_crl, revoked, asn1_int
+ self._sorted_crl, revoked, asn1_int
)
if res == 0:
return None
@@ -251,7 +261,7 @@
revoked[0] != self._backend._ffi.NULL
)
return _RevokedCertificate(
- self._backend, self._x509_crl, revoked[0]
+ self._backend, self._sorted_crl, revoked[0]
)
@property
diff --git a/tests/x509/test_x509.py b/tests/x509/test_x509.py
index a866d81..4ce4d95 100644
--- a/tests/x509/test_x509.py
+++ b/tests/x509/test_x509.py
@@ -550,6 +550,35 @@
assert crl[2:4][0].serial_number == crl[2].serial_number
assert crl[2:4][1].serial_number == crl[3].serial_number
+ def test_get_revoked_certificate_doesnt_reorder(self, backend):
+ private_key = RSA_KEY_2048.private_key(backend)
+ last_update = datetime.datetime(2002, 1, 1, 12, 1)
+ next_update = datetime.datetime(2030, 1, 1, 12, 1)
+ builder = x509.CertificateRevocationListBuilder().issuer_name(
+ x509.Name([
+ x509.NameAttribute(NameOID.COMMON_NAME, u"cryptography.io CA")
+ ])
+ ).last_update(
+ last_update
+ ).next_update(
+ next_update
+ )
+ for i in [2, 500, 3, 49, 7, 1]:
+ revoked_cert = x509.RevokedCertificateBuilder().serial_number(
+ i
+ ).revocation_date(
+ datetime.datetime(2012, 1, 1, 1, 1)
+ ).build(backend)
+ builder = builder.add_revoked_certificate(revoked_cert)
+ crl = builder.sign(private_key, hashes.SHA256(), backend)
+ assert crl[0].serial_number == 2
+ assert crl[2].serial_number == 3
+ # make sure get_revoked_certificate_by_serial_number doesn't affect
+ # ordering after being invoked
+ crl.get_revoked_certificate_by_serial_number(500)
+ assert crl[0].serial_number == 2
+ assert crl[2].serial_number == 3
+
@pytest.mark.requires_backend_interface(interface=RSABackend)
@pytest.mark.requires_backend_interface(interface=X509Backend)