Public key AuthMethod

[biran@il.ibm.com]

In Minneapolis I proposed to add the public key AuthMethod based on
SPKM (public key implementation of GSS-API, RFC-2025). SPKM is really
suitable (it gives the exact definition of tokens to be exchange in iSCSI
text
messages for public key authentication including optional certificates
exchange, and MAC digest based on shared key generated by the
exchange, that might be negotiated in the iSCSI login).

However, there is a question mark about the status of RFC-2025. It is on
standards truck at Proposed Standard level, but it is from 1996... I had
a correspondence with the CAT-WG chair, and here are two citations:

"I'm unaware, however, of any current plans for advancement of this
document
beyond Proposed and it hasn't been actively discussed within the WG for
some
time. I'm also unsure as to its number of existing implementations."

"Nonetheless, I believe that it remains well suited as a specification for
an
X.509-based authentication mechanism.  I'm not aware of an alternative
specification with comparable scope currently defined within an Internet
standards-track RFC"

(BTW, if you look at the version linked from the RFC pages, the
"Status of this Memo" section states:
"This memo defines an Experimental Protocol for the Internet community..."
however the same section in the version fetched from the RFC Editor-pages
states:
"This document specifies an Internet standards track protocol for the
   Internet community..."
the CAT-WG chair confirmed that the first copy is a mistake.)

In anyway, can we (/ should we) rely on RFC that its plan for becoming a
standard is not clear at all?

Another option for the public key AuthMethod might be a reduced version
of the TLS handshake (implemented in the iSCSI text messages, not using
the TLS record layer).  This can provide authentication (with optional
certificate exchange) and a shared secret that can be used for MAC
digest according to the TLS MAC specification (but used of course as
optional iSCSI digest and not inside TLS).

I believe it's preferable to adopt an existing security standard as much
as possible than inventing something new for iSCSI.

I'd like to hear some opinions on these before we decide how to define
the public key AuthMethod.

Regards,
  Ofer


Ofer Biran
Storage and Systems Technology
IBM Research Lab in Haifa
biran@il.ibm.com  972-4-8296253