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Re: byte order
>>>>> "C" == C Harald Koch <chk@utcc.utoronto.ca> writes:
C> ...
C> In the case of DES, the inputs and outputs are all octet strings,
C> at least in every definition I've seen.
Matt Thomas said much the same thing.
Part of the reason I raised the issue is that all the DES descriptions
I have (such as FIPS 46, though admittedly the 1977 edition) describe
DES as a BLOCK cypher, operating on 64 bit blocks. Neither FIPS 46
nor 1026 nor 1027, as far as I can find, describe any mapping of octet
strings into DES blocks.
Another consideration is that I couldn't readily tell the byte order
of a popular DES implementation (the one by Eric Young); some of what
it does suggests it might be little endian, but the way it describes
the IP suggests that it may be big endian after all.
Unless there is a clear statement of the octet string mapping to DES
blocks in some existing document (if so, I'd appreciate a pointer) I
feel very strongly that this has to be added to the (3)DES transform
specs.
paul
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