[Python-Dev] new features for 2.3?

[Guido van Rossum]

> I have always wondered, why does both ``cPickle`` (which uses camel-style
> naming which I thought was a no-no)  and ``Pickle``?  They do exactly the
> same thing (in theory).

pickle.py is the specification of the protocol; cPickle.c is a
reimplementation that's up to 1000x faster.  I always prototype new
features in pickle.py.

> Is there any other place where security has been built into
> something?  Sounds like we should do a security inaudit (is that a
> word?) and rip out pretty much all security code.

There's very little code devoted specifically to security.  However,
there's a feature called "restricted mode", and in restricted mode,
certain introspections are disallowed.  Restricted mode is on when a
particular stack frame's __builtins__ dictionary isn't the default one
(which is __builtin__.__dict__ -- note the difference between
__builtin__, which is a module, and __builtins__, which is a global
with magic meaning).  Read the source for PyFrame_New().

It turns out that in 2.2 and beyond, not enough restrictions were
placed on disallowing new introspections that were enabled by virtue
of the class/type integration, and that's the cause of most rexec
vulnerabilities.

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