Simon Josefsson simon@josefsson.org writes:
and the link for "algorithm specification" is
I think this is the authoritative spec, and same document which was included in the submission package (floppy5/serpent.pdf).
The user key length is variable, but for the purposes of this submission we fix it at 128, 192 or 256 bits
That is a bit vague, either it is variable or it isn't.
I agree, this is not as definitive as I remembered it. Anyway, it defines how short keys of any bitsize <= 256 bits should be padded, in case anybody ever wants to use it, and gives 40-bit keys as an example.
The Serpent-0 specification says
The user key can be of any length between 64 and 256 bits.[5]
[5] We define key lengths to be multiples of 32 bits for ease of implementation, and ...
I don't think this is relevant.
Regards, /Niels