W3C home > Mailing lists > Public > public-xmlsec@w3.org > June 2011

RE: Special cases for PrefixRewrite in C14N 2.0 ( LC-2486)

From: Pratik Datta <pratik.datta@oracle.com>
Date: Tue, 14 Jun 2011 11:47:44 -0700 (PDT)
Message-ID: <5f3cea2f-ac45-41ef-a845-5d4db36357da@default>
To: frederick.hirsch@nokia.com
Cc: public-xmlsec@w3.org
Yes, I agree with the resolution.

Pratik

-----Original Message-----
From: frederick.hirsch@nokia.com [mailto:frederick.hirsch@nokia.com] 
Sent: Monday, June 13, 2011 8:18 AM
To: Pratik Datta
Cc: public-xmlsec@w3.org
Subject: Re: Special cases for PrefixRewrite in C14N 2.0 ( LC-2486)


 Dear Pratik Datta ,

The XML Security Working Group has reviewed the comments you sent [1] on
the Last Call Working Draft [2] of the Canonical XML Version 2.0 published
on 21 Apr 2011. Thank you for having taken the time to review the document
and to send us comments!

The Working Group's response to your comment is included below.

Please review it carefully and let us know by email at
public-xmlsec@w3.org if you agree with it or not before 28 June 2011. In
case of disagreement, you are requested to provide a specific solution for
or a path to a consensus with the Working Group. If such a consensus cannot
be achieved, you will be given the opportunity to raise a formal objection
which will then be reviewed by the Director during the transition of this
document to the next stage in the W3C Recommendation Track.

Thanks,

For the XML Security Working Group,
Thomas Roessler
W3C Staff Contact

 1. http://www.w3.org/mid/97690808-8f1e-4dca-a4dd-58cede862fbb@default
 2. http://www.w3.org/TR/2011/WD-xml-c14n2-20110421/


=====

Your comment on 2.5.2 Namespace processing algorithm Step 1: At first
deter...:
> For these following three XML documents 1, 2, and 3 here is what I think
> they should canonicalize to with prefixRewrite according to the current
> spec - 1a, 2a and 3a. But I have also put an alternative  for each - 1b,
> 2b and 3b.    
> 
>  
> 
> Example 1:  with namespace redefinition
> 
>  
> 
> <a:foo xmlns:a="http://a1">
> 
>   <a:bar xmlns:a="http://a2"/>
> 
> </a:foo>
> 
>  
> 
> In the above example at first  prefix "a" is defined to  namespace
> http://a1  and then redefined to http://a2
> 
>  
> 
> With prefix rewriting should prefix "a" be rewritten to two different
> namespaces ns0 and ns1? Or should it be one namespace ns0 with
> redefinition.   I.e. should it be 
> 
>  
> 
> 1a)
> 
> <ns0:foo xmlns:ns0="http://a1" >
> 
>   <ns1:bar xmlns:ns1="http://a2"/>
> 
> </ns0:foo>
> 
>  
> 
> Or should it be 
> 
>  
> 
> 1b)
> 
> <ns0:foo xmlns:ns0="http://a1" >
> 
>   <ns0:bar xmlns:ns0="http://a2"/>
> 
> </ns0:foo>
> 
>  
> 
> I think the spec says it should be 1a)
> 
>  
> 
>  
> 
>  
> 
> Example 2: with two prefixes defining the same namespace
> 
> <a:foo xmlns:a="http://a1">
> 
>   <b:bar xmlns:b="http://a1"/>
> 
> </a:foo>
> 
>  
> 
> In this example both "a" and "b" are defined to the same namespace 
> http://a1
> 
>  
> 
> So should they be rewritten to two different prefixes or to the same
> prefix?
> 
>  
> 
> I.e. should it be canonicalized to
> 
> 2a)
> 
> <ns0:foo xmlns:ns0="http://a1">
> 
>   <ns1:bar xmlns:ns1="http://a1"/>
> 
> </ns0:foo>
> 
>  
> 
> Or should it be 
> 
> 2b)
> 
> <ns0:foo xmlns:ns0="http://a1">
> 
>   <ns0:bar/>
> 
> </ns0:foo>
> 
>  
> 
> Again I think the spec says it should be 2a).       But maybe 2b) makes
> more sense, i.e. should we say that each URI should be mapped to one
> prefix?
> 
>  
> 
>  
> 
> Example 3: With prefixes being pushed down
> 
> <a:foo xmlns:a="http://a1" xmlns:b="http://a2" >
> 
>   <b:bar>
> 
>   <b:bar>
> 
> </a:foo>
> 
>  
> 
> Should each b get mapped to different prefixes?  I.e. Should it be
> 
>  
> 
> 3a)
> 
> <ns0:foo xmlns:ns0="http://a1" >
> 
>   <ns1:bar xmlns:ns1="http://a2" >
> 
>   <ns2:bar xmlns:ns2="http://a2" >
> 
> </ns0:foo>
> 
>  
> 
> Or should it be
> 
> 3b)
> 
> <ns0:foo xmlns:ns0="http://a1" >
> 
>   <ns1:bar xmlns:ns1="http://a2" >
> 
>   <ns1:bar xmlns:ns1="http://a2" >
> 
> </ns0:foo>
> 
>  
> 
>  
> 
> Again according to the spec , it should be 3a)
> 
>  
> 
> I am thinking that we should change the definition of prefixRewrite so
> that we go by URI and not by prefix.  i.e.  each visibility utilized
> prefix gets mapped to a new prefix, so that there is a 1:1 mapping
> between URIs and new prefixes, but not a 1:1 mapping between original
> prefixes and new prefixes.  With this definition  we would get 1a), 2b
> and 3b) which I think makes more sense.
> 
>  
> 
>  
> 
> Pratik


Working Group Resolution (LC-2486):
http://lists.w3.org/Archives/Public/public-xmlsec/2011Jun/0002.html

Changes for prefix rewrite
 - Added new section 2.5.2 Namespace Prefix Rewriting
 - Modified section 2.5.3 , Removed Step 1, and added a new Step 3 for
prefix rewriting
 - Changed example 2.5.4.2,   earlier the wsu prefix would map to n1, and
then n2. Now it maps to n1 only



----
Received on Tuesday, 14 June 2011 18:48:33 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 14 June 2011 18:49:30 GMT