Ben Laurie <[EMAIL PROTECTED]> writes: >Anne & Lynn Wheeler wrote: >> Peter Gutmann wrote: >>> That cuts both ways though. Since so many systems *do* screw with >>> data (in >>> insignificant ways, e.g. stripping trailing blanks), anyone who does >>> massage >>> data in such a way that any trivial change will be detected is going >>> to be >>> inundated with false positives. Just ask any OpenPGP implementor about >>> handling text canonicalisation. >> >> this was one of the big issues in the asn.1 encoding vis-a-vis xml >> encoding wars. >> >> asn.1 encoding provided deterministic encoding for signed material, > >You mean it _would_ have done if anyone could implement it correctly. Sadly, >experience shows that no-one can.
Right, but that's lead to a de-facto encoding rule of "The originator encodes it however they like, and everyone else re-encodes it (if required) using memcpy()". The advantage of the format is that it's never tried to be anything other than a pure binary-only format, so moving it over text-only channels is handled at the next layer down (usually base64), rather than trying to make the encoding itself text-only-capable and then finding yourself in a world of pain when half the systems the stuff passes through mangle the text. Peter. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]