bpo-31453: Add setter for min/max protocol version (#5259)
OpenSSL 1.1 has introduced a new API to set the minimum and maximum
supported protocol version. The API is easier to use than the old
OP_NO_TLS1 option flags, too.
Since OpenSSL has no call to set minimum version to highest supported,
the implementation emulate maximum_version = MINIMUM_SUPPORTED and
minimum_version = MAXIMUM_SUPPORTED by figuring out the minumum and
maximum supported version at compile time.
Signed-off-by: Christian Heimes <christian@python.org>
diff --git a/Lib/ssl.py b/Lib/ssl.py
index 75ebcc1..2db8873 100644
--- a/Lib/ssl.py
+++ b/Lib/ssl.py
@@ -112,9 +112,11 @@
pass
-from _ssl import HAS_SNI, HAS_ECDH, HAS_NPN, HAS_ALPN, HAS_TLSv1_3
-from _ssl import _DEFAULT_CIPHERS
-from _ssl import _OPENSSL_API_VERSION
+from _ssl import (
+ HAS_SNI, HAS_ECDH, HAS_NPN, HAS_ALPN, HAS_SSLv2, HAS_SSLv3, HAS_TLSv1,
+ HAS_TLSv1_1, HAS_TLSv1_2, HAS_TLSv1_3
+)
+from _ssl import _DEFAULT_CIPHERS, _OPENSSL_API_VERSION
_IntEnum._convert(
@@ -153,6 +155,16 @@
_SSLv2_IF_EXISTS = getattr(_SSLMethod, 'PROTOCOL_SSLv2', None)
+class TLSVersion(_IntEnum):
+ MINIMUM_SUPPORTED = _ssl.PROTO_MINIMUM_SUPPORTED
+ SSLv3 = _ssl.PROTO_SSLv3
+ TLSv1 = _ssl.PROTO_TLSv1
+ TLSv1_1 = _ssl.PROTO_TLSv1_1
+ TLSv1_2 = _ssl.PROTO_TLSv1_2
+ TLSv1_3 = _ssl.PROTO_TLSv1_3
+ MAXIMUM_SUPPORTED = _ssl.PROTO_MAXIMUM_SUPPORTED
+
+
if sys.platform == "win32":
from _ssl import enum_certificates, enum_crls
@@ -467,6 +479,25 @@
self._load_windows_store_certs(storename, purpose)
self.set_default_verify_paths()
+ if hasattr(_SSLContext, 'minimum_version'):
+ @property
+ def minimum_version(self):
+ return TLSVersion(super().minimum_version)
+
+ @minimum_version.setter
+ def minimum_version(self, value):
+ if value == TLSVersion.SSLv3:
+ self.options &= ~Options.OP_NO_SSLv3
+ super(SSLContext, SSLContext).minimum_version.__set__(self, value)
+
+ @property
+ def maximum_version(self):
+ return TLSVersion(super().maximum_version)
+
+ @maximum_version.setter
+ def maximum_version(self, value):
+ super(SSLContext, SSLContext).maximum_version.__set__(self, value)
+
@property
def options(self):
return Options(super().options)