John the Ripper is a fast password cracker, currently available for many flavors of Unix (11 are officially supported, not counting different architectures), Win32, DOS, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types which are most commonly found on various Unix flavors, as well as Kerberos AFS and Windows NT/2000/XP LM hashes. Several other hash types are added with contributed patches. License: GNU General Public License (GPL) Changes:
This release focuses on better x86-64 support. Most notably, two Blowfish-based crypt(3) hashes may now be computed in parallel for much better performance on x86-64, and new make targets have been added for Mac OS X 10.5+ (Leopard) and recent versions of Solaris on 64-bit capable x86 processors, producing 64-bit builds that make use of the 64-bit mode extended SSE2. As a bonus, "DumbForce" and "KnownForce" external mode samples have been added to the default john.conf.

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