Make the lib and ffi public for the OpenSSL binding and document them
diff --git a/docs/bindings/index.rst b/docs/bindings/index.rst
new file mode 100644
index 0000000..80f5359
--- /dev/null
+++ b/docs/bindings/index.rst
@@ -0,0 +1,7 @@
+Bindings
+========
+
+.. toctree::
+    :maxdepth: 1
+
+    openssl
diff --git a/docs/bindings/openssl.rst b/docs/bindings/openssl.rst
new file mode 100644
index 0000000..144ed9b
--- /dev/null
+++ b/docs/bindings/openssl.rst
@@ -0,0 +1,23 @@
+OpenSSL
+=======
+
+These are `CFFI`_ bindings to the `OpenSSL`_ C library.
+
+.. data:: cryptography.bindings.openssl.api
+
+    This is the exposed API for the OpenSSL bindings. It has two public
+    attributes:
+
+    .. attribute:: ffi
+
+        This is a :class:`cffi.FFI` instance. It can be used to allocate and
+        otherwise manipulate OpenSSL structures.
+
+    .. attribute:: lib
+
+        This is a ``cffi`` library. It can be used to call OpenSSL functions,
+        and access constants.
+
+
+.. _`CFFI`: http://cffi.readthedocs.org/
+.. _`OpenSSL`: https://www.openssl.org/
diff --git a/docs/index.rst b/docs/index.rst
index c8f6388..5cc455f 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -32,5 +32,6 @@
 
     architecture
     primitives/index
+    bindings/index
     contributing
     community