RE: Encrypting entire documents in XML Proposal?

It is true that well-formed documents require a prologue but it is
also true that the prologue may be empty.  In other words,

<?xml version="1.0" encoding="UTF-16"?>
<root>
<a><b>
</root>

is well-formed but so is

<root>
<a><b>
</root>

In both cases, if encrypting the entire XML instance, one
would end up with

<EncryptedData Type="Document" 
               xmlns=".../xml/encryption">
...
</EncryptedData>

which is also a well-formed document which has an empty prologue and
is therefore, by default, UTF-8 and version 1.0.

A question which remains to be answered is whether this model
stands the test of various character encodings.  I believe 
Hiroshi and Takeshi feel that various character encodings could
cause problems (Hiroshi and Takeshi, please correct me if I
misunderstand).  As for me, I expect that there could be a
problem here, but I don't want to introduce a requirement for
canonicalization unless I see proof of it.  

Ed 
-----Original Message-----
From: Thane Plambeck [mailto:tplambeck@verisign.com]
Sent: Thursday, December 21, 2000 12:57 PM
To: 'xml-encryption@w3.org'
Subject: FW: Encrypting entire documents in XML Proposal?










In section 5.7 of this doc (encrypting an entire XML document)
perhaps the prologue should not be encrypted?  At least we perserve
well-formedness then for entire documents.

I realize that encrypting just the root element and not the prologue
is already covered by the case of encrypting an entire element.
So I guess the question is, should XML Encryption really say anything
about encrypting entire documents, including the prologue?  If it does
then we are left with the consequence of XML Document encryption leaving
us with non-well formed XML, which requires a prologue.  


Thane






Thane Plambeck
tplambeck@verisign.com
http://www.verisign.com
650 429 5247 direct, Mt View Office
650 321 4884 home office
650 323 4928 home office fax



-----Original Message-----
From: Blair Dillaway [mailto:blaird@microsoft.com]
Sent: Friday, December 15, 2000 2:41 PM
To: xml-encryption@w3.org
Cc: Hiroshi Maruyama; Brian LaMacchia; Barb Fox; 'Ed Simon'; 'Takeshi
Imamura'; jimsch@nwlink.com
Subject: Proposal for XML Encryption Syntax and Processing


We respectfully submit the attached specification 
as a suggested starting point for the XML Encryption Working 
Group effort.  This work builds on earlier papers and 
on-going discussions.

We look forward to comments and continuing discussions 
to resolve the open issues identified in this document.

Regards,
Blair Dillaway, Barbara Fox, Takeshi Imamura, 
Brian LaMacchia, Hiroshi Maruyama, Jim Schaad, 
Ed Simon