zopefoundation / RestrictedPython

A restricted execution environment for Python to run untrusted code.

RestrictedPython

RestrictedPython is a tool that helps to define a subset of the Python language which allows to provide a program input into a trusted environment. RestrictedPython is not a sandbox system or a secured environment, but it helps to define a trusted environment and execute untrusted code inside of it.

Warning

RestrictedPython only supports CPython. It does _not_ support PyPy and other Python implementations as it cannot provide its restrictions there.

For full documentation please see http://restrictedpython.readthedocs.io/.

Example

To give a basic understanding what RestrictedPython does here two examples:

An unproblematic code example

Python allows you to execute a large set of commands. This would not harm any system.

>>> from RestrictedPython import compile_restricted
>>> from RestrictedPython import safe_globals
>>>
>>> source_code = """
... def example():
...     return 'Hello World!'
... """
>>>
>>> loc = {}
>>> byte_code = compile_restricted(source_code, '<inline>', 'exec')
>>> exec(byte_code, safe_globals, loc)
>>>
>>> loc['example']()
'Hello World!'

Problematic code example

This example directly executed in Python could harm your system.

>>> from RestrictedPython import compile_restricted
>>> from RestrictedPython import safe_globals
>>>
>>> source_code = """
... import os
...
... os.listdir('/')
... """
>>> byte_code = compile_restricted(source_code, '<inline>', 'exec')
>>> exec(byte_code, safe_globals, {})
Traceback (most recent call last):
ImportError: __import__ not found

Contributing to RestrictedPython

If you want to help maintain RestrictedPython and contribute, please refer to the documentation Contributing page.