topic Re: New john the ripper patch in Operating System - OpenVMS

New john the ripper patch

David Jones_21 — Wed, 22 Jul 2009 12:50:22 GMT

I attached a zip file with a new patch for John the Ripper (1.7.3.1) to support OpenVMS password hashes. The major difference between this patch and the 2002 patch by Jean-loup Gailly is that this version supports mixed-case passwords (UAI flag UAI$M_PWDMIX). It is also multi-threaded, increasing performance up to 50-65% on a dual-processor system (splitting your password file into multiple jobs is probably more effective).

The only builds done so far are on OpenVMS Alpha 8.3, OS X 10.5.7 (Mac Mini), and an old PC linux distro.

Re: New john the ripper patch

David Jones_21 — Thu, 06 Aug 2009 13:14:01 GMT

I've refined the patch to improve performance and attached a new kit.

The first refinement is a rewrite of the exponentiation function, which had it's long-ago origin as transliterated VAX macro. I changed a complicated loop into 2 simpler loops that the compiler has an easier time optimizing. I then applied Gailly's exponent factorization trick to the hash computation. My comments, though, give a more correct analysis of the effect of the optimization (38 extended precision multiplies versus 48).

Re: New john the ripper patch

vman — Sun, 21 Aug 2011 17:03:10 GMT

I made a new patch kit compatible with John the Ripper 1.7.8. There were only minor changes.