CLIF the StreamingAead primitive.

PiperOrigin-RevId: 268436776

cc/python/streaming_aead.clif

+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from "tink/python/util/clif.h" import *  # StatusOr
+
+from "tink/cc/streaming_aead.h":
+  namespace `crypto::tink`:
+    # Interface for streaming authenticated encryption with associated data.
+    # Streaming encryption is typically used for encrypting large plaintexts
+    # such as large files. This interface supports a streaming interface for
+    # symmetric encryption with authentication. The underlying encryption modes
+    # are selected so that partial plaintext can be obtained fast by decrypting
+    # and authenticating just a part of the ciphertext.
+    class StreamingAead:
+        # Intentionally empty.
+        #
+        # The cliffed CC primitive's only purpose is to be stored as a member
+        # variable and later be passed to a wrapper function (which sidesteps
+        # cliffing an OutputStream). Therefore Python doesn't need to know about
+        # its methods, just that it exists.
+        pass