[pycrypto] FYI: PyCrypto on Google App Engine

Dwayne C. Litzenberger dlitz at dlitz.net
Sun May 3 10:49:54 CST 2009

On Sat, May 02, 2009 at 03:15:42PM +0200, Mads Kiilerich wrote:
> http://code.google.com/appengine/docs/python/tools/libraries.html#PyCrypto
> App Engine includes a custom version of the Python Cryptography Toolkit 
> <http://www.amk.ca/python/code/crypto>, also known as PyCrypto. The version 
> included with App Engine is based on pycrypto 2.0.1. This is not the latest 
> version <http://pycrypto.org>, but should be largely compatible with more 
> recent versions.

Neat.  Thanks for pointing this out.

> For reasons both technical and legal, the App Engine version of PyCrypto 
> has the following differences from the original PyCrypto 2.0.1:
>    * The RC5 and IDEA ciphers have been removed.

Makes sense.  RC5 and IDEA are patent-encumbered.

>    * The MODE_PGP encryption mode has been removed.

Hmm.  Does anybody know why MODE_PGP would have been removed?

>    * All public key cryptography routines are implemented in pure
>      Python code. They do not use any native acceleration (C code).

In other words, they built PyCrypto without the optional support for libgmp 

Dwayne C. Litzenberger <dlitz at dlitz.net>
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