dlitz/pycrypto — pull request #14 by stefanor (2012-05-27 12:19:04+00:00)
Title: Make IVs optional again

As mentioned in [#997464](https://bugs.launchpad.net/pycrypto/+bug/997464/comments/2), a side-effect of the IV-length checking patch was to require IVs for all modes using IVs.
In the past, and in the documentation, IVs defaulted to all-zeroes if not provided.

This patch restores that behavior.