John the Ripper 是一个快速的口令破解器 ，支持多种操作系统，如Unix、DOS、Win32、BeOS和OpenVMS等。它设计的主要目的是用于检查 Unix系统的弱口令，支持几乎所有Unix平台上经crypt函数加密后的口令哈希类型，也支持Kerberos AFS和Windows NT/2000 /XP LM哈希等。目前John the Ripper更新至1.7.8版,新版主要改变如下:

  • The bitslice DES S-box expressions have been replaced with those generated by Roman Rusakov specifically for John the Ripper.  The corresponding assembly
  •  code for x86 with MMX, SSE2, and for x86-64 with SSE2 has been re-generated. For other CPUs and for AVX/XOP, C compilers do a reasonably good job of generating the code from the supplied C source files (with intrinsics where relevant).  The S-box expressions that we were using before had a 21% larger gate count, so theoretically this could provide a 21% speedup.  In practice, though, a 12% to 14% speedup at DES-based crypt(3) hashes is typical. This effort has been sponsored by Rapid7
  •  Corrected support for bcrypt (OpenBSD Blowfish) hashes of passwords containing non-ASCII characters (that is, characters with the 8th bit set). Added support for such hashes produced by crypt_blowfish up to 1.0.4, which contained a sign extension bug (inherited from older versions of John). The old buggy behavior may be enabled per-hash, using the “$2x$” prefix.
  •  The external mode virtual machine’s performance has been improved through additional multi-op instructions matching common instruction sequences
  •  (assign-pop and some triple- and quad-push VM instructions were added).
  •  A few minor bug fixes and enhancements were made.

工具下载:http://download.openwall.net/pub/projects/john/1.7.8/