Peter,
You would be correct if we were talking about PKCS#7 where ContentInfo was used
within SignedData to carry the content. This would clearly have to be optional
in the detached signature case. But, in CMS we now only use ContentInfo for
carrying SignedData, EnvelopedData etc., so even when detached signatures are
being used the Content field of ContentInfo must be present to carry your
SignedData.
I agree with John and other posters that the definition in the main body of the
document is correct. Content is not optional.
Regards,
Darren
--------------------------------------------------------------------------------
Darren Harter BSc (Hons) CEng MBCS
Entegrity Solutions
E-Mail: dharter(_at_)sapher(_dot_)com
Tel: +44 (0) 1452 371 383, or +44 (0) 181 876 8666
Fax: +44 (0) 1452 371 384, or +44 (0) 181 876 8660
Cell: +44 (0) 7801 812 850
-----Original Message-----
From: Peter Gutmann [SMTP:pgut001(_at_)cs(_dot_)auckland(_dot_)ac(_dot_)nz]
Sent: Tuesday, February 23, 1999 3:46 AM
To: ietf-smime(_at_)imc(_dot_)org;
ross(_at_)jgross(_dot_)demon(_dot_)co(_dot_)uk
Subject: Re: Correct definition of ContentInfo in CMS-10
The content is optional. Think about how detached sigs work.
Peter.