[Python-Dev] Algoritmic Complexity Attack on Python (original) (raw)

Guido van Rossum guido@python.org
Sat, 31 May 2003 12:55:21 -0400

On Fri, May 30, 2003 at 08:41:54PM -0400, Guido van Rossum wrote: > Of course, such programs are already vulnerable to changes in the hash > implementation between Python versions (which has happened before).

Is there at least a guarantee that the hashing algorithm won't change in a bugfix release? For instance, can I depend that python222 -c 'print hash(1), hash("a")' python223 -c 'print hash(1), hash("a")' will both output the same thing, even if python23 -c 'print hash(1), hash("a")' and python3000 -c 'print hash(1), hash("a")' may print something different?

That's a reasonable assumption, yes. We realize that changing the hash algorithm is a feature change, even if it is a very subtle one.

--Guido van Rossum (home page: http://www.python.org/~guido/)