[10662] in cryptography@c2.net mail archive
Re: ciphersaber-2 human memorable test vectors
daemon@ATHENA.MIT.EDU (Bill Frantz)
Fri Mar 29 20:40:40 2002
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Date: Fri, 29 Mar 2002 13:49:30 -0800
To: Adam Back <adam@cypherspace.org>, cryptography@wasabisystems.com
From: Bill Frantz <frantz@pwpconsult.com>
Cc: Anton Stiglic <stiglic@cs.mcgill.ca>
At 10:15 AM -0800 3/26/02, Adam Back wrote:
>In general purely human readable test vectors are not ideal as they
>are 7 bit, and there have been cases where implementation errors or
>related to the 7th bit (for example one blowfish implementation had
>problems with signd / unsigned chars), but it is kind of an
>interesting though experiment.
If this issue seems to be a problem for a particular cypher, there are a
couple of ways to try to solve it:
* Compress out the eighth bit (requiring 10 characters for a 64 bit block
cypher instead of 8).
* Remember a pattern of high order bits. Something like 11110000 would be
relatively easy to remember, and would help mitigate signed vs. unsigned
number problems on 32 bit machines.
Cheers - Bill
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