GPL command-line shred alternative for Windows

Ryan Malayter
Fri Nov 9 22:55:01 2001

Hmm... I'll have to look into that. There must be some differences between
the way CryptoAPI is called on 9x versus NT/2k, although that didn't appear
to be the case from the CryptGenRandom() documentation in the MS platform
SDK. According to that, all versions of Windows newer than 95A have
CryptoAPI functionality.

Perhaps I'll add code to gshred for the ISAAC random number generator, and
then allow a manual RNG seed for systems that don't have CryptoAPI. I
thought about doing that from the start, but CryptoAPI seemed to be a good
way to get secure random numbers without user input. (CryptoAPI's entropy
pool is similar to Linux's /dev/random - it slowly hashes in entropy based
on user activity on the system).

I'm copying this to the gnupg-list in the faint hope that someone else might
know of a better a way to get at the Windows entropy pool other than

:::Ryan Malayter, MCSE
:::Bank Administration Institute
:::Chicago, Illinois, USA

-----Original Message-----
From: Samuel }slund [] 
Sent: Friday, November 09, 2001 6:17 AM
To: Ryan Malayter
Subject: Re: GPL command-line shred alternative for Windows


I just tested gshred on a vanilla Windows 98 machine and got this result:

gshred: overwrote with 1s
gshred: overwrote with 0s
gshred: overwrote with 1s
gshred: overwrote with 0s
gshred: unable to get CryptoAPI context.


Notice that it handles the long filename ok.
An option to skip the random overwrite would quickly make it (less secure
but) usable on Windows 98.

Just a thought.

(Who do not have a Mingw32 instalation.)