Re: [smime] FW: I-D Action:draft-freeman-message-access-control-req-00.txt

["Jim Schaad" <[e-mail]>]

I have additionally released two documents which provide a potential method
of implementing the requirements

These are:
      http://www.ietf.org/id/draft-schaad-eps-smime-00.txt  which describes
the additions to the CMS and S/MIME formats to support the concept and
     http://www.ietf.org/id/draft-schaad-eps-trust-00.txt which gives a
possible description of how to communicate between the mail client and the
enforcement server.

Jim


> -----Original Message-----
> From: [e-mail] [mailto:[e-mail]] On Behalf
> Of Trevor Freeman
> Sent: Friday, January 21, 2011 9:28 AM
> To: Smime ([e-mail])
> Subject: [smime] FW: I-D Action:draft-freeman-message-access-control-req-
> 00.txt
> 
> This should be of interest to members of the members of the list.
> 
> -----Original Message-----
> From: [e-mail] [mailto:i-d-announce-
> [e-mail]] On Behalf Of [e-mail]
> Sent: Thursday, January 20, 2011 3:15 PM
> To: [e-mail]
> Subject: I-D Action:draft-freeman-message-access-control-req-00.txt
> 
> A New Internet-Draft is available from the on-line Internet-Drafts
directories.
> 
> 	Title           : Requirements for Message Access Control
> 	Author(s)       : T. Freeman, et al.
> 	Filename        : draft-freeman-message-access-control-req-00.txt
> 	Pages           : 17
> 	Date            : 2011-01-20
> 
> There are many situations where organizations want to include
>   information which is subject to regulatory or other complex access
>   control policy in email. Regulated information requires some form of
>   robust access control to protect the confidentiality of the
>   information. The Enhanced Security Services for S/MIME [rfc2634]
>   defines an access control mechanism for S/MIME (eSSSecurityLabel).
>   This is a signed attribute of a SignedData object which indicates the
>   access control policy for the message. The fact that this is a signed
>   attribute protects the integrity of the data and the binding of the
>   label to the message but does not protect the confidentiality of the
>   information i.e. at the point where you lean the access control policy
>   to the data you also have access to the data. While the signature
>   provides integrity for the label over the clear text, it is
>   susceptible to unauthorized removal i.e. if you only have SignedData
>   message, any MTA in the mail path can remove a signature layer and
>   therefore remove the access control data.  Encrypting the signed
>   message protects the confidentiality of the data and protects the
>   SignedData from unauthorized removal but this hides the ESS security
>   label.
> 
>   From a regulatory enforcement perspective this is an extremely weak
>   form of access control because cryptographic access to the data is
>   given before the access check. The correct enforcement of the access
>   check totally depends on the configuration of the recipients email
>   client. Since the cryptographic access is granted before the access
>   checks, there is no significant impediment for a recipient who is
>   unauthorized under the policy to access the data. A stronger
>   enforcement model is needed for regulatory control for email where
>   cryptographic access is only granted after the access check.
> 
>   There are also many users on the Internet today who have some form of
>   authentication credential but they are not X.509 certificates and who
>   therefore cannot use S/MIME. There are now available, standard based
>   services (e.g. [SAML-overview]) which abstract the specifics of a
>   technology used to authenticate uses from the application itself (S/MIME
in
> this case). Adoption of this abstraction model would enable
>   a broader set of users who have other types to authentication
>   credentials to be able to use S/MIME to secure email. It also allows
>   for new authentication technology to be deployed without impacting the
>   core S/MIME protocol.
> 
>   This document specifies the requirements for:-
> 
> 
> Providing robust access control for S/MIME
> 
> 
> An abstraction layer for supporting other types of credentials for
> 
> using S/MIME.
> 
> A URL for this Internet-Draft is:
> http://www.ietf.org/internet-drafts/draft-freeman-message-access-
> control-req-00.txt
> 
> Internet-Drafts are also available by anonymous FTP at:
> ftp://ftp.ietf.org/internet-drafts/
> 
> Below is the data which will enable a MIME compliant mail reader
> implementation to automatically retrieve the ASCII version of the
Internet-
> Draft.