John the Ripper, a password cracker.

[rahimonline]

John the Ripper is a password cracker, currently available for UNIX, DOS, WinNT and Win95. Its primary purpose is to detect weak UNIX passwords. It has been tested with Linux x86/Alpha/SPARC, FreeBSD x86, OpenBSD x86, Solaris 2.x SPARC and x86, Digital UNIX, AIX, HP-UX, and IRIX.

It contains a lot of features and performance optimizations over the well-known "Crack" password cracker. John the Ripper combines several cracking modes in one program, and is fully configurable for your particular needs (you can even define a custom-cracking mode using the built-in compiler supporting a subset of the C programming language). Also, John is available for several different platforms, which enables you to use the same cracker everywhere (for example, you can even continue a cracking session that you started on another platform). Out of the box, John supports (and autodetects) the following ciphertext formats: standard and double-length DES-based, BSDI's extended DES-based, FreeBSD's (and not only) MD5-based, and OpenBSD's Blowfish-based.

With just one extra command (required to extract the passwords), John can crack AFS passwords and WinNT LM hashes.

Unlike other crackers, John doesn't use a crypt(3)-style routine. Instead, it has its own highly optimized modules for different ciphertext formats and architectures. Some of the algorithms used couldn't be implemented in a crypt(3)-style routine: they require a more powerful interface (bitslice DES is an example). Additionally, there're assembly routines for several processors and architectures (special Intel Pentium version, x86 with MMX, generic x86, Alpha EV4, SPARC V8).

John the Ripper v1.6 (UNIX -- source distribution) can be downloaded from: http://www.false.com/security/john/john-1.6.tar.gz John the Ripper v1.6 (DOS -- binaries) can be downloaded from: http://www.false.com/security/john/john-16d.zip John the Ripper v1.6 (Win32 -- binaries) can be downloaded from: http://www.false.com/security/john/john-16w.zip. A few ftp sites mirror the distribution: ftp://ftp.cdrom.com/.3/security/coas...alse.com/john/ ftp://ftp.hkstar.com/.3/COAST/mirror...alse.com/john/ ftp://ftp.rge.com/pub/security/coast...alse.com/john/