Re: signature overview question/comment


I more or less made up the format. It was intended to be a way to give
a less detailed skeleton so you could see the structure without being
buried in details.

If I recall properly, initially <> meant that either there was no
element content or the element content was given explicitly while ()
meant there was element content that was suppressed. But what's there
now has been changed considerably from the initial version....

I don't really care that much at this point and would be happy to
go with your version.


From:  Amir Herzberg <>
Message-ID:  <078EE8822DCFD411AAA1000629D56ADC0B7E7C@IMP01>
To:  "Dsig (E-mail)" <>
Date:  Tue, 14 Aug 2001 15:15:54 +0300

>At section 2.0 there's a simplified overview of DSIG structure:
>     <SignedInfo>
>       (CanonicalizationMethod)
>       (SignatureMethod)
>       (<Reference (URI=)? >
>         (Transforms)?
>         (DigestMethod)
>         (DigestValue)
>       </Reference>)+
>     </SignedInfo>
>     (SignatureValue) 
>    (KeyInfo)?
>    (Object)*
>I think this text is pretty old, definitely before I first looked at the
>draft. So I have some questions, and please excuse me if this was discussed
>already (probably long ago) on the list:
>1. Is this a common format?
>2. Is there a reason that some tags are given as tags, e.g. SignedInfo,
>while others are without the brackets, e.g. SignatureValue? 
>3. Is there a reason that some mandatory elements are in parenthesis, e.g.
>CanonicalizationMethod, while others are not, e.g. SignedInfo?
>4. Is it correct that when a parenthesis is closed without "?", "+" or "*",
>then the element should appear exactly once? If so, it may be clearer to use
>a sign for `appear exactly once`, e.g. the numeral 1. Or better yet simply
>not put such element in parenthesis. 
>Just in case all the above points are simply minor mistakes, here's a
>potential new text:
>     <SignedInfo>
>       <CanonicalizationMethod>
>       <SignatureMethod>
>       (<Reference (URI=)? >
>         (<Transforms>)?
>         <DigestMethod>
>         <DigestValue>
>       </Reference>)+
>     </SignedInfo>
>     <SignatureValue>
>    (<KeyInfo>)?
>    (<Object>)*
>Best regards, 
>Amir Herzberg
>CTO, NewGenPay Inc.  
>SMS (urgent only!): _subject_ of email to

Received on Tuesday, 21 August 2001 22:40:33 UTC