- From: Joseph Reagle <reagle@w3.org>
- Date: Wed, 11 Sep 2002 14:49:16 -0400
- To: "Richard Whitcomb" <rwhitcomb@inforev.com>, "'Paul Grosso'" <pgrosso@arbortext.com>, "'Richard Tobin'" <richard@cogsci.ed.ac.uk>
- Cc: "'XML Signature \(W3C/IETF\)'" <w3c-ietf-xmldsig@w3.org>
On Wednesday 11 September 2002 01:16 pm, Richard Whitcomb wrote: > I don't agree that changes would be required to exc-c14n, but would like > to hear more about why this would be the case. I don't think this is the case either, but I'm not sure. My present understanding is all the specs would have to change anyway to normatively reference NS 1.1, and while I think I know what would have to be done, I'm content to have the denizens of the future be sure of the details! <smile/> The example I'm thinking is: <a xmlns="http://example.com/default" xmlns:foo="http://example.com/foo" foo:value="f"> <b xmlns:foo=""> <c/> </b> </a> Where the subset "c" is selected for canonicalization. Now of course, you couldn't use c14n or exc-c14n presently because xmlns:foo="" is an illegal NS 1.0 . But let's assume were making new versions for NS 1.1. At first I was thinking the Canonical Form (without any other changes to the spec) would be: <c xmlns="http://example.com/default" xmlns:foo=""/> At least that's what would happen in the python implementation, but if we're using a NS1.1 compliant parser the xmlns:foo won't be in the namespace axis anyway so the actual result would be: <c xmlns="http://example.com/default"/> (I'd have to tweak the implementation to do this since we don't have axis to a real namespace axis but pull them out of the attribute axis...) The Exclusive Canonical Form (without any other changes to the spec other than to permit xmlns:foo="") would also be: <c xmlns="http://example.com/default"/> and I know I wouldn't have to make any changes to my code even because "unutilized" namespace/prefix declarations are never emitted, and there's no way a valid XML document would have a prefix in use for which there was not a declaration.
Received on Wednesday, 11 September 2002 14:49:47 UTC