Proof of concept that we can use bytes or buffers

TODO.md

@@ -1,3 +1,7 @@
+- Anything which takes bytes should be able to take a bytearray or memoryview
+  as well. See: http://docs.cython.org/src/userguide/memoryviews.html
+
+
 - expose all the pkcs5/oaep/pss padding functions
 - passing `hash=None` to sign/verify will cause it to assume it was passed a digest
 

src/cipher.pyx

@@ -348,7 +348,7 @@ cdef class Cipher(Descriptor):
             len(header)))
 
     % for type in 'encrypt decrypt'.split():
-    cpdef ${type}(self, bytes input):
+    cpdef ${type}(self, input_):
         """${type}(input)
 
         ${type.capitalize()} a string.
@@ -365,17 +365,31 @@ cdef class Cipher(Descriptor):
 
         % endif
         """
+
+        # Accept something that can be coerced into a writable buffer, or
+        # directly into a pointer.
+        # TODO: abstract this into a utility somewhere for further use.
+        cdef unsigned char[::1] input_view
+        cdef unsigned char *input_ptr
         cdef int length
-        length = len(input)
+        try:
+            input_view = input_
+            length = input_view.shape[0] * input_view.itemsize
+            input_ptr = &input_view[0]
+        except BufferError:
+            input_ptr = input_
+            length = len(input_)
+
         # We need to make sure we have a brand new string as it is going to be
         # modified. The input will not be, so we can use the python one.
         output = PyBytes_FromStringAndSize(NULL, length)
+
         % for mode, i in cipher_mode_items:
         ${'el' if i else ''}if self.mode_i == ${i}: # ${mode}
             % if mode in cipher_auth_modes:
-            check_for_error(${mode}_${type}(<${mode}_state*>&self.state, input, output, length))
+            check_for_error(${mode}_${type}(<${mode}_state*>&self.state, input_ptr, output, length))
             % else:
-            check_for_error(${mode}_${type}(input, output, length, <symmetric_${mode}*>&self.state))
+            check_for_error(${mode}_${type}(input_ptr, output, length, <symmetric_${mode}*>&self.state))
             % endif
         % endfor
         return output

tests/test_cipher.py

@@ -120,3 +120,11 @@ def test_api(self):
         msg = b'hello, world'
         enc = cipher.aes(key, iv).encrypt(msg)
         self.assertEqual(cipher.aes(key, iv).decrypt(enc), msg)
+
+    def test_bytearrays(self):
+        key = b'0123456789abcdef'
+        iv  = b'0' * 16
+        msg = bytearray(b'hello, world')
+        enc = cipher.aes(key, iv).encrypt(msg)
+        self.assertEqual(cipher.aes(key, iv).decrypt(enc), msg)
+