Support loading a custom TLS server name from kubeconfig

kubernetes_asyncio/client/configuration.py

@@ -189,6 +189,10 @@ def __init__(self, host=None,
         self.assert_hostname = None
         """Set this to True/False to enable/disable SSL hostname verification.
         """
+        self.tls_server_name = None
+        """SSL/TLS Server Name Indication (SNI)
+           Set this to the SNI value expected by Kubernetes API.
+        """
 
         self.connection_pool_maxsize = 100
         """This value is passed to the aiohttp to limit simultaneous connections.

kubernetes_asyncio/client/rest.py

@@ -56,6 +56,8 @@
                 configuration.cert_file, keyfile=configuration.key_file
             )
 
+        self.server_hostname = configuration.tls_server_name
+
         if not configuration.verify_ssl:
             ssl_context.check_hostname = False
             ssl_context.verify_mode = ssl.CERT_NONE
@@ -135,6 +137,9 @@
         if query_params:
             args["url"] += '?' + urlencode(query_params)
 
+        if self.server_hostname:
+            args["server_hostname"] = self.server_hostname
+
         # For `POST`, `PUT`, `PATCH`, `OPTIONS`, `DELETE`
         if method in ['POST', 'PUT', 'PATCH', 'OPTIONS', 'DELETE']:
             if (

kubernetes_asyncio/config/kube_config.py

@@ -393,14 +393,16 @@ def _load_cluster_info(self):
                         temp_file_path=self._temp_file_path).as_file()
         if 'insecure-skip-tls-verify' in self._cluster:
             self.verify_ssl = not self._cluster['insecure-skip-tls-verify']
+        if 'tls-server-name' in self._cluster:
+            self.tls_server_name = self._cluster['tls-server-name']
 
     def _set_config(self, client_configuration):
 
         if 'token' in self.__dict__:
             client_configuration.api_key['BearerToken'] = self.token
 
         # copy these keys directly from self to configuration object
-        keys = ['host', 'ssl_ca_cert', 'cert_file', 'key_file', 'verify_ssl']
+        keys = ['host', 'ssl_ca_cert', 'cert_file', 'key_file', 'verify_ssl', 'tls_server_name']
         for key in keys:
             if key in self.__dict__:
                 setattr(client_configuration, key, getattr(self, key))

kubernetes_asyncio/config/kube_config_test.py

@@ -72,6 +72,7 @@ def _raise_exception(st):
 TEST_CLIENT_KEY_BASE64 = _base64(TEST_CLIENT_KEY)
 TEST_CLIENT_CERT = "client-cert"
 TEST_CLIENT_CERT_BASE64 = _base64(TEST_CLIENT_CERT)
+TEST_TLS_SERVER_NAME = "kubernetes.io"
 
 TEST_OIDC_TOKEN = "test-oidc-token"
 TEST_OIDC_INFO = "{\"name\": \"test\"}"
@@ -443,6 +444,13 @@ class TestKubeConfigLoader(BaseTestCase):
                     "user": "exec_cred_user_certificate"
                 }
             },
+            {
+                "name": "tls-server-name",
+                "context": {
+                    "cluster": "tls-server-name",
+                    "user": "ssl"
+                }
+            },
         ],
         "clusters": [
             {
@@ -488,6 +496,16 @@ class TestKubeConfigLoader(BaseTestCase):
                     "insecure-skip-tls-verify": False,
                 }
             },
+            {
+                "name": "tls-server-name",
+                "cluster": {
+                    "server": TEST_SSL_HOST,
+                    "certificate-authority-data":
+                        TEST_CERTIFICATE_AUTH_BASE64,
+                    "insecure-skip-tls-verify": False,
+                    "tls-server-name": TEST_TLS_SERVER_NAME,
+                }
+            },
         ],
         "users": [
             {
@@ -863,6 +881,22 @@ async def test_ssl_verification(self):
             active_context="ssl_verification").load_and_set(actual)
         self.assertEqual(expected, actual)
 
+    async def test_tls_server_name(self):
+        expected = FakeConfig(
+            host=TEST_SSL_HOST,
+            token=BEARER_TOKEN_FORMAT % TEST_DATA_BASE64,
+            cert_file=self._create_temp_file(TEST_CLIENT_CERT),
+            key_file=self._create_temp_file(TEST_CLIENT_KEY),
+            ssl_ca_cert=self._create_temp_file(TEST_CERTIFICATE_AUTH),
+            verify_ssl=True,
+            tls_server_name=TEST_TLS_SERVER_NAME
+        )
+        actual = FakeConfig()
+        await KubeConfigLoader(
+            config_dict=self.TEST_KUBE_CONFIG,
+            active_context="tls-server-name").load_and_set(actual)
+        self.assertEqual(expected, actual)
+
     def test_list_contexts(self):
         loader = KubeConfigLoader(
             config_dict=self.TEST_KUBE_CONFIG,

requirements.txt

@@ -4,4 +4,4 @@ python-dateutil>=2.5.3  # BSD
 setuptools>=21.0.0  # PSF/ZPL
 urllib3>=1.24.2  # MIT
 pyyaml>=3.12  # MIT
-aiohttp>=3.7.0,<4.0.0 # # Apache-2.0
+aiohttp>=3.9.0,<4.0.0 # # Apache-2.0

scripts/rest_client_server_hostname_patch.diff

@@ -0,0 +1,23 @@
+diff --git a/kubernetes_asyncio/client/rest.py b/kubernetes_asyncio/client/rest.py
+index c5be7990..9e0daab4 100644
+--- a/kubernetes_asyncio/client/rest.py
++++ b/kubernetes_asyncio/client/rest.py
+@@ -56,6 +56,8 @@ class RESTClientObject(object):
+                 configuration.cert_file, keyfile=configuration.key_file
+             )
+
++        self.server_hostname = configuration.tls_server_name
++
+         if not configuration.verify_ssl:
+             ssl_context.check_hostname = False
+             ssl_context.verify_mode = ssl.CERT_NONE
+@@ -135,6 +137,9 @@ class RESTClientObject(object):
+         if query_params:
+             args["url"] += '?' + urlencode(query_params)
+
++        if self.server_hostname:
++            args["server_hostname"] = self.server_hostname
++
+         # For `POST`, `PUT`, `PATCH`, `OPTIONS`, `DELETE`
+         if method in ['POST', 'PUT', 'PATCH', 'OPTIONS', 'DELETE']:
+             if re.search('json', headers['Content-Type'], re.IGNORECASE):

scripts/update-client.sh

@@ -68,6 +68,8 @@ echo ">>> fix generated rest client for patching with strategic merge..."
 patch "${CLIENT_ROOT}/client/rest.py" "${SCRIPT_ROOT}/rest_client_patch.diff"
 echo ">>> fix generated rest client by increasing aiohttp read buffer to 2MiB..."
 patch "${CLIENT_ROOT}/client/rest.py" "${SCRIPT_ROOT}/rest_client_patch_read_bufsize.diff"
+echo ">>> fix generated rest client to support customer server hostname TLS verification..."
+patch "${CLIENT_ROOT}/client/rest.py" "${SCRIPT_ROOT}/rest_client_server_hostname_patch.diff"
 
 
 echo ">>> Remove invalid tests (workaround https://github.com/OpenAPITools/openapi-generator/issues/5377)"