* Eirik: > On 5 August 2015 22:35:10 CEST, Florian Weimer <f...@deneb.enyo.de> wrote: >>Suppose I have a sequence of words over some alphabet, and I want to >>compute a cryptographically secure hash over that. Simply >>concatenating the hashes to form a single word does not work because >>the word boundaries might have been meaningful and not implicit in the >>inputs, and then you have second preimages etc. I guess this is why >>we have DER, among other reasons. > > Isn't the normal way to effectively introduce an alphabet A' that is a > superset of A plus a word separator? You know like A=a-z A'=A+ space?
Explicit framing instead of quoting/escaping is probably more robust and easier to implement, at least for digest computation. >>I've been asked to provide some citation for this observation, but I >>can't find a proper reference. Any suggestions? > > Isn't this trivial? {a,aa} != {aaa} ? I think it is, but sufficiently many people accept something as true only if it is published in a peer-reviewed paper. _______________________________________________ cryptography mailing list cryptography@randombit.net http://lists.randombit.net/mailman/listinfo/cryptography