[mailto:owner-ietf-smime(_at_)mail(_dot_)imc(_dot_)org] On Behalf Of Denis
Sent: Wednesday, May 03, 2006 4:55 PM
Subject: Re: I-D ACTION:draft-ietf-smime-escertid-01.txt
I have several problems with draft-ietf-smime-escertid-01.txt.
In RFC 2634, we have section "5.4 called Signing Certificate
The proposal is to add a section 5.4.1 to define the v2
version first (!) and then the current version (with SHA-1).
This should be done in the reverse way:
- first a section 5.4.1 to define the current version (with SHA-1),
- then a section 5.4.2 to define the v2 version.
I prefer the existing ordering. I would rather have the items that people
are to be using occur first and then obsolete items rather than the other
way around. I have not changed this.
After this restructuring, I have some problems with the text itself :
Issue 1 (page 4):
"Applications SHOULD recognize both attributes as long as
they consider SHA-1 to be sufficiently descriminating".
"descriminating" is not crystal clear for me. Would it be
possible to have the same idea expressed using a different wording ?
Issue 2 (pages 4 & 5):
There is a duplication of the same paragraph (one is enough):
"The signing certificate attribute is designed to prevent
substitution and re-issue attacks, and to allow for a
of authorization certificates to be used in verifying a signature".
I believe that not having any descriptive text at these locations and
jumping directly into the ASN.1 to be a poor choice. I have not changed
Issue 3 (page 7):
"The issuer/serial number pair would therefore normally be
to identify the correct signing certificate. (This
assumes the same
issuer name is not re-used from the set of trust anchors.)"
The assumption between the parenthesis is insufficient to
correctly identify the correct signing certificate. The
sentence needs to be changed.
I do not understand your statement. If the statement in parenthesis is
true, then it is sufficent. If the statement in the parenthesis is not
true, then issuer/serial number is not sufficent. Please re-read the text
and explain better what your problem is.
Issue 4 (page 7):
"In the cases
where the issuer/serial number pair is not used in the sid or the
issuer/serial number need to be signed, they should be
placed in the
issuerSerial field of the ESSCertIDv2 structure."
The issuer/serial number pair can be used in the sid, but
since it is unsigned, it is insufficient to correctly
identify the correct signing certificate.
So this rational is incorrect. The sentence needs to be changed.
I have no idea what you are trying to state here. My sentence and your
comment do not seem to be coming from the same context. Please re-read the
Finally, I would propose that the next draft proposes a
for section 5.4 to make sure that the whole section is consistent
(and that the text in it is not redondant).
I can understand your concern, however I believe that the current layout is
better and more explicit for the RFC editor.
A New Internet-Draft is available from the on-line
This draft is a work item of the S/MIME Mail Security
Working Group of the IETF.
Title : ESS Update: Adding CertID Algorithm Agility
Author(s) : J. Schaad
Filename : draft-ietf-smime-escertid-01.txt
Pages : 18
Date : 2006-4-18
In the original Enhanced Security Services for S/MIME draft, a
structure for cryptographically linking the certificate to be used in
validation with the signature was introduced, this structure was
hardwired to use SHA-1. This document allows for the structure to
have algorithm agility and defines new attributes to deal with the
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