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From: Lowell Gilbert <freebsd-questions-local@be-well.ilk.org>
To: doug@safeport.com
References: <20101118145239.10937b78@adolfputzen>
	<alpine.BSF.2.00.1011181013090.97870@fledge.watson.org>
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Cc: freebsd-questions@freebsd.org, Julian Fagir <gnrp@physik.tu-berlin.de>
Subject: Re: Escaping from shell-scripts
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doug <doug@fledge.watson.org> writes:

> If you make a program a shell AFAIK to escape is to logff. Bash has a
> chroot like facility that might work. However if you write a simple C
> program as a wrapper for your shell script and make that program a
> shell, I would think that is pretty secure.

As long as you don't call anything that can create an inferior shell.
A common mistake when doing this kind of thing is to allow some file
editing or mail reading, using programs that have a "shell escape"
capability.