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The following archive was created by hippie-mail 7.98617-22 on Fri Aug 21 1998 - 17:18:23 ADT
Peter Gutmann (pgut001@cs.auckland.ac.nz)
Sat, 6 Jun 1998 02:54:10 (NZST)
>>I am looking for hardware accelerator cards that include DES/Triple
>>DES (additional symmetric key algorthms okay). They must run on
>>Windows computers. Most likely they will be PCI cards.
>http://www.ce-infosys.com/english/oem/index.htm
>The databooks for the SuperCrypt part have enough sample code to get it up and
>running from scratch.
The CEI chips are rather nice to work with, they're very easy to program and
have some nice features (red/black separation in the hardware, encrypted key
load, and various other things). One thing about the CEI-supplied drivers,
they're rather inefficient and a bit difficult to use. I wrote my own drivers
which auto-detect the hardware (without hanging the machine in the presence of
broken hardware like some NE2000 clones which lock up the system if you probe
them), and which do more or less what the CEI drivers do in a few hundred
bytes instead of 20-30K. The CEI software also tends to concentrate on single
DES, which I wasn't too interested in since the hardware does triple DES just
as well.
The chips have a 3-stage pipelined DES implementation where you have to push
in two more 64-bit blocks before the first one drops out, the idea behind
doing efficient drivers is to keep the pipeline full at all times. The driver
I wrote does this and gets (for the ISA card) exactly 1.0MB/s throughput,
which indicates it's doing all you can on the ISA bus. That's not too
spectacular for pure DES, but it's not bad for triple DES on an old 386 (you'd
need about a PII-300 to do the same in software for 3DES-CBC, something which
didn't appear until several years after I wrote the code). In any case the
limiting factor is the bus interface, the chips are capable of doing 20MB/s on
a proper bus (newer cards have a PCI interface so you can actually make use of
this throughput). Because you can get them on ISA/PCI cards, you can develop
and debug the drivers using standard PC development tools before you use them
in an embedded application.
The SuperCrypt chips are rather nice, they do all the usual modes (ECB, CFB,
CBC, OFB) in the hardware, have onboard storage for 8 (from memory, this was
some time ago) keys (so 8 single DES or 2-and-a-bit triple DES keys), and
user-loadable S-boxes (so you can use Biham's method of getting a larger
effective keysize with user-defined S-boxes).
If anyone's working with the SuperCrypt chips and wants the drivers I wrote,
let me know. The only condition is that you have to send me any changes you
make. It'd be nice if someone could do drivers for newer OS's for them
(Win'95 or NT).
>Finally, if you need to do this internationally, you're in luck, they are
>german company.
They tend to be a bit stuffy about selling them to you though, I don't know
what it's like getting them from outside Germany. It's easiest to get someone
over there to get them for you.
If anyone's after one of the cards, I've got a spare one here which has never
been used - I'll have to go back and figure out what the thing's worth if
anyone wants it.
Peter.
The following archive was created by hippie-mail 7.98617-22 on Fri Aug 21 1998 - 17:18:23 ADT