diff --git a/cryptography/bindings/openssl/api.py b/cryptography/bindings/openssl/api.py
index ee6e49d..abdaef0 100644
--- a/cryptography/bindings/openssl/api.py
+++ b/cryptography/bindings/openssl/api.py
@@ -57,6 +57,7 @@
         if res == 0:
             # TODO: figure out openssl errors
             raise Exception
+        # TODO: this should depend on mode.padding
         self._lib.EVP_CIPHER_CTX_set_padding(ctx, 0)
         return ctx