add cast5 (cbc, cfb, ofb) vector source info to docs

1 files changed, 26 insertions, 0 deletions

diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index 2a071d7c..3b8632e6 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -54,8 +54,34 @@ Symmetric Ciphers
 * Camellia (ECB) from NTT's `Camellia page`_ as linked by `CRYPTREC`_.
 * Camellia (CBC, CFB, OFB) from `OpenSSL's test vectors`_.
 * CAST5 (ECB) from :rfc:`2144`.
+* CAST5 (CBC, CFB, OFB) generated by this project.
+  See: :doc:`/development/custom-vectors/cast5`
 
 
+Creating Test Vectors
+---------------------
+
+When official vectors are unavailable ``cryptography`` may choose to build
+its own using existing vectors as source material. Current custom vectors:
+
+.. toctree::
+    :maxdepth: 1
+
+    custom-vectors/cast5
+
+If official test vectors appear in the future the custom generated vectors
+should be discarded.
+
+Any vectors generated by this method must also be prefixed with the following
+header format (substituting the correct information):
+
+.. code-block:: python
+
+    # CAST5 CBC vectors built for https://github.com/pyca/cryptography
+    # Derived from the AESVS MMT test data for CBC
+    # Verified against the CommonCrypto and Go crypto packages
+    # Key Length : 128
+
 .. _`NIST`: http://www.nist.gov/
 .. _`IETF`: https://www.ietf.org/
 .. _`NIST CAVP`: http://csrc.nist.gov/groups/STM/cavp/