"Safe" Embedded Python

[Chris Liechti]

Gerhard Häring <gh_pythonlist at gmx.de> wrote in
news:mailman.1009917181.18293.python-list at python.org: 
> Le 01/01/02 à 12:16, Hervey Wilson écrivit:
>> I am contemplating embedding Python in my application in order to
>> support end-user scripting. Having done some initial investigation, I
>> am happy with the functionality that I can expose but now I find
>> myself concerned with safety / security, specifically I want to limit
>> scripting activities to the core language features and the object
>> model that my application exposes. Put another way, I don't want the
>> scripts to be able to read / write to the hard-disk, open sockets and
>> so on. 
>> 
>> Can anyone provide some tips / links on the viability of doing this
>> and any implementation examples ? 
> 
> I've never done this myself, but I can give a few tips:
> 
> The rexec module might offer most of what you need.

yes with rexec and bastion you can control what modules and classes are 
available to the client.
you can write a open and import filter and let pass the files/modules you 
want and block on others.

bastion protects your classes you want to expose to the client (e.g. real 
private attributes).

> You'll need to restrict the modules users can import and remove some
> builtins, like with:
> 
> del __builtins__.__dict__['open']

there is only one __builtins__ and when you remove the open function not 
even the server can write files... better use rexec, its simpler and saver.
 
> The rexec module probably already offers this, I haven't checked.
> 
> In the PostgreSQL source tree (http://www.postgresql.org/) you can find
> plpython, a module for implementing server-side Python procedures for
> the PostgreSQL database. I have seen it restricts the modules you can
> load.
> 
> Gerhard



-- 
Chris <cliechti at gmx.net>