4 files changed, 211 insertions, 0 deletions
diff --git a/cryptography/hazmat/primitives/block/__init__.py b/cryptography/hazmat/primitives/block/__init__.py
new file mode 100644
index 00000000..5b8942b6
--- /dev/null
+++ b/cryptography/hazmat/primitives/block/__init__.py
@@ -0,0 +1,21 @@
+# 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
+
+from cryptography.hazmat.primitives.block.base import BlockCipher
+
+
+__all__ = [
+    "BlockCipher",
+]
diff --git a/cryptography/hazmat/primitives/block/base.py b/cryptography/hazmat/primitives/block/base.py
new file mode 100644
index 00000000..ece3b32d
--- /dev/null
+++ b/cryptography/hazmat/primitives/block/base.py
@@ -0,0 +1,56 @@
+# 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
+
+from cryptography.hazmat.primitives import interfaces
+
+
+class BlockCipher(object):
+    def __init__(self, cipher, mode, backend=None):
+        super(BlockCipher, self).__init__()
+
+        if backend is None:
+            from cryptography.hazmat.bindings import (
+                _default_backend as backend,
+            )
+
+        self.cipher = cipher
+        self.mode = mode
+        self._backend = backend
+
+    def encryptor(self):
+        return _CipherContext(
+            self._backend.ciphers.create_encrypt_ctx(self.cipher, self.mode))
+
+    def decryptor(self):
+        return _CipherContext(
+            self._backend.ciphers.create_decrypt_ctx(self.cipher, self.mode))
+
+
+@interfaces.register(interfaces.CipherContext)
+class _CipherContext(object):
+    def __init__(self, ctx):
+        self._ctx = ctx
+
+    def update(self, data):
+        if self._ctx is None:
+            raise ValueError("Context was already finalized")
+        return self._ctx.update(data)
+
+    def finalize(self):
+        if self._ctx is None:
+            raise ValueError("Context was already finalized")
+        data = self._ctx.finalize()
+        self._ctx = None
+        return data
diff --git a/cryptography/hazmat/primitives/block/ciphers.py b/cryptography/hazmat/primitives/block/ciphers.py
new file mode 100644
index 00000000..4143b89d
--- /dev/null
+++ b/cryptography/hazmat/primitives/block/ciphers.py
@@ -0,0 +1,78 @@
+# 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 = frozenset([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 ({0}) for {1}".format(
+                self.key_size, self.name
+            ))
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+class Camellia(object):
+    name = "camellia"
+    block_size = 128
+    key_sizes = frozenset([128, 192, 256])
+
+    def __init__(self, key):
+        super(Camellia, 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 ({0}) for {1}".format(
+                self.key_size, self.name
+            ))
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+class TripleDES(object):
+    name = "3DES"
+    block_size = 64
+    key_sizes = frozenset([64, 128, 192])
+
+    def __init__(self, key):
+        super(TripleDES, self).__init__()
+        if len(key) == 8:
+            key += key + key
+        elif len(key) == 16:
+            key += key[:8]
+        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 ({0}) for {1}".format(
+                self.key_size, self.name
+            ))
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
diff --git a/cryptography/hazmat/primitives/block/modes.py b/cryptography/hazmat/primitives/block/modes.py
new file mode 100644
index 00000000..a60e8a34
--- /dev/null
+++ b/cryptography/hazmat/primitives/block/modes.py
@@ -0,0 +1,56 @@
+# 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
+
+from cryptography.hazmat.primitives import interfaces
+
+
+@interfaces.register(interfaces.ModeWithInitializationVector)
+class CBC(object):
+    name = "CBC"
+
+    def __init__(self, initialization_vector):
+        super(CBC, self).__init__()
+        self.initialization_vector = initialization_vector
+
+
+class ECB(object):
+    name = "ECB"
+
+
+@interfaces.register(interfaces.ModeWithInitializationVector)
+class OFB(object):
+    name = "OFB"
+
+    def __init__(self, initialization_vector):
+        super(OFB, self).__init__()
+        self.initialization_vector = initialization_vector
+
+
+@interfaces.register(interfaces.ModeWithInitializationVector)
+class CFB(object):
+    name = "CFB"
+
+    def __init__(self, initialization_vector):
+        super(CFB, self).__init__()
+        self.initialization_vector = initialization_vector
+
+
+@interfaces.register(interfaces.ModeWithNonce)
+class CTR(object):
+    name = "CTR"
+
+    def __init__(self, nonce):
+        super(CTR, self).__init__()
+        self.nonce = nonce