FAQ 8.11 How do I decode encrypted password files?
in [Perl]
|
Prev: How to submit utility - not module - to CPAN
Next: FAQ 4.57 What happens if I add or remove keys from a hash while iterating over it?
From: PerlFAQ Server on 21 Jun 2010 12:00 This is an excerpt from the latest version perlfaq8.pod, which comes with the standard Perl distribution. These postings aim to reduce the number of repeated questions as well as allow the community to review and update the answers. The latest version of the complete perlfaq is at http://faq.perl.org . -------------------------------------------------------------------- 8.11: How do I decode encrypted password files? You spend lots and lots of money on dedicated hardware, but this is bound to get you talked about. Seriously, you can't if they are Unix password files--the Unix password system employs one-way encryption. It's more like hashing than encryption. The best you can do is check whether something else hashes to the same string. You can't turn a hash back into the original string. Programs like Crack can forcibly (and intelligently) try to guess passwords, but don't (can't) guarantee quick success. If you're worried about users selecting bad passwords, you should proactively check when they try to change their password (by modifying passwd(1), for example). -------------------------------------------------------------------- The perlfaq-workers, a group of volunteers, maintain the perlfaq. They are not necessarily experts in every domain where Perl might show up, so please include as much information as possible and relevant in any corrections. The perlfaq-workers also don't have access to every operating system or platform, so please include relevant details for corrections to examples that do not work on particular platforms. Working code is greatly appreciated. If you'd like to help maintain the perlfaq, see the details in perlfaq.pod. |