1 files changed, 34 insertions, 0 deletions
diff --git a/cryptography/primitives/block/ciphers.py b/cryptography/primitives/block/ciphers.py
new file mode 100644
index 00000000..2e478705
--- /dev/null
+++ b/cryptography/primitives/block/ciphers.py
@@ -0,0 +1,34 @@
+# 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 __future__ import absolute_import, division, print_function
+
+
+class AES(object):
+    name = "AES"
+    block_size = 128
+    key_sizes = set([128, 192, 256])
+
+    def __init__(self, key):
+        super(AES, self).__init__()
+        self.key = key
+
+        # Verify that the key size matches the expected key size
+        if self.key_size not in self.key_sizes:
+            raise ValueError("Invalid key size (%s) for %s".format(
+                self.key_size, self.name
+            ))
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8