Learn about taint mode in Perl and Ruby. How does it compare to sandbox creation via binary rewriting, as described in Sidebar 16.5? What sorts of security problems does it catch? What sorts of...

Learn about taint mode in Perl and Ruby. How does it compare to sandbox creation via binary rewriting, as described in Sidebar 16.5? What sorts of security problems does it catch? What sorts of problems does it not catch? Learn about proof-carrying code, a technique in which the supplier of mobile code includes a proof of its safety, and the user simply verifies the proof, rather than regenerating it (start with the work of Necula [Nec97]). How does this technique compare to other forms of sandboxing? What properties can it guarantee?