Re: Multiple signatures on multiple files

"David Wall" <[email protected]> Mon, 29 Jul 2002 11:54:15 -0700
Newsgroups gmane.ietf.xmldsig
Organization Yozons, Inc.
Message-ID <[email protected]>
> Signing "real data", i.e. signing the message directly is not such a good
idea as it opens the algorithm to some attacks, especially if you use plain
RSA (which would be a very bad idea).

True, but a lot of typical signing includes a hash (RSA/DSA with SHA1), but
the SHA1 works against the actual data being signed (in both digital
signature and legal sense).  In XML Signature, there's a two step process of
doing an SHA1 on the actual data, and then digital signing (hash the hash
and encrypt with the private key), so the digital signature is "signing" a
hash, not the original data.  Anyway, I believe it's sound technically, just
wondered if there's anything "odd" from a legal standpoint since the
signature is once removed from the data being signed.

David