Re: Chartering work has started for a Linked Data Signature Working Group @W3C

On Fri, 2021-06-04 at 19:38 +0100, Dan Brickley wrote:
> 
> 
> On Fri, 4 Jun 2021 at 19:28, Peter Patel-Schneider <  
> pfpschneider@gmail.com> wrote

[...]
> :
> > 
> > I'm coming to the conclusion that there is no way to reliably sign
> > and
> > verify JSON-LD documents as linked data.  About all I'm willing to
> > guess is that it is likely possible to reliably sign and verify
> > NQUADS
> > documents that do not contain relative IRIs 
> > 
> 
> 
> If the relative IRIs are in a syntactic context that expects IRIs,
> then it would be invalid NQUAD syntax.
> 
> https://www.w3.org/TR/n-quads/#sec-iri
> 
> “ IRIs may be written only as absolute IRIs.”
> 
> ... so presumably careful software would object strenuously.


I thought that this was the case but then the grammar for NQuads didn't
seem to have any restrictions on the form of the IRIREF so I
incorrectly convinced myself that relative IRIs were allowed.  My
mistake.

> 
> > or blank nodes because
> > canonicalization reduces to canonicalizing IRIs and strings,
> > removing
> > comments, and then sorting the file and eliminating duplicate
> > lines.
> > 
> 
> 
> I don’t follow this point
> 
> Dan

Part of the process of signing an LD document is coming up with the
canonical serialization of "the" RDF dataset that it serializes.  For
NQuad documents that don't have blank nodes you don't need to do much
to come up with a canonical form, just make sure that the IRIREFs and
literals are in canonical form and then sort the lines of the document
and remove any duplicates.  Or at least this is all that I think is
required.

peter

Received on Friday, 4 June 2021 19:00:37 UTC