From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Thu, 17 Oct 1996 11:07:17 +0200
From: Boyd Roberts boyd@france3.fr
Subject: encrypt/decrypt not thread safe
Topicbox-Message-UUID: 4f7addbe-eac8-11e9-9e20-41e7f4b1d025
Message-ID: <19961017090717.lLRHkeqDxa62UVb4--TtSifHg5G90gWdirxicEPJnt8@z>

    From: forsyth@plan9.cs.york.ac.uk

    boyd might be able to offer a safe replacement that's not subject
    to pointless controls.

you can certainly take my des from ftp://www.plan9.cs.su.oz.au/~boyd/des.msg
but it's not thread safe.  it assumes it's being called by a single
threaded program.  to fix it you need to have a per thread expanded
key.  all you need to do is to change deskey() to accept a parameter
for where to store the expanded key , rather than storing it in a
global static.  not real hard.