Archive for the ‘IETF’ Category

RFC6125 “TLS/SSL Server Identity Check” is published

Tuesday, April 5th, 2011

RFC6125TLS/SSL Server Identity Check” (aka “TLS Server ID Check“, “SSL Server ID
Check
“, “TLS/SSL Server ID Check“, “SSL Server ID“) is now available:

Representation and Verification of Domain-Based Application Service
Identity within Internet Public Key Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer Security (TLS)


http://tools.ietf.org/html/rfc6125

Alas, we messed up by not including this “short form” title directly in the spec:

TLS/SSL Server Identity Check

But hopefully people will know what spec is meant if someone uses that short-form title.

I’ve written about the spec and its background before:

of TLS/SSL Server Identity Checking

Although we produced the spec without a formal working group, many people contributed to it one way or another. From the Contributors and Acknowledgments sections:

The following individuals made important contributions to the text of this document: Shumon Huque, RL ‘Bob’ Morgan, and Kurt Zeilenga.

The editors and contributors wish to thank the following individuals for their feedback and suggestions: Bernard Aboba, Richard Barnes, Uri Blumenthal, Nelson Bolyard, Kaspar Brand, Anthony Bryan, Scott Cantor, Wan-Teh Chang, Bil Corry, Dave Cridland, Dave Crocker, Cyrus Daboo, Charles Gardiner, Philip Guenther, Phillip Hallam-Baker, Bruno Harbulot, Wes Hardaker, David Harrington, Paul Hoffman, Love Hornquist Astrand, Henry Hotz, Russ Housley, Jeffrey Hutzelman, Cullen Jennings, Simon Josefsson, Geoff Keating, John Klensin, Scott Lawrence, Matt McCutchen, Alexey Melnikov, Subramanian Moonesamy, Eddy Nigg, Ludwig Nussel, Joe Orton, Tom Petch, Yngve N. Pettersen, Tim Polk, Robert Relyea, Eric Rescorla, Pete Resnick, Martin Rex, Joe Salowey, Stefan Santesson, Jim Schaad, Rob Stradling, Michael Stroeder, Andrew Sullivan, Peter Sylvester, Martin Thomson, Paul Tiemann, Sean Turner, Nicolas Williams, Dan Wing, Dan Winship, and Stefan Winter.

Thanks also to Barry Leiba and Ben Campbell for their reviews on behalf of the Security Directorate and the General Area Review Team, respectively.

The responsible Area Director was Alexey Melnikov.

(i.e. 59 people besides PeterSA and myself (wow))

TLS/SSL Server Identity Check will be RFC6125

Tuesday, March 15th, 2011

As I’ve previously mentioned, I’ve been working on a specification for “TLS/SSL Server Identity Checking” along with Peter Saint-Andre.

We’ve now heard back from the RFC Editor, and we’re in the so-called “AUTH48 state” where we, the spec’s authors/editors, work with the RFC Editor folks to turn the Internet-Draft into a RFC.

At this point we know the RFC number-to-be: 6125.

So, we’re close to getting this thing out the door, whew. :)

‘HTTP State Management Mechanism’ (”cookies”) to Proposed Standard

Monday, March 7th, 2011

There’s been various fundamental issues with “HTTP cookies” for ages, e.g. technically and policy-wise (i.e. privacy). The two extant formal specifications of cookies, IETF RFCs 2109 and 2965, as well as the original informal and incomplete “Netscape cookie spec”, have not been implemented uniformly across browsers and servers. Thus how cookies are actually constructed, parsed, and used in practice has been essentially technical folklore. Anyone wanting to craft a new browser or some other application or tool that needs to consume or send cookie headers had to reverse engineer how the browsers were actually doing it as there wasn’t (until now) an accurate specification an implementer could use for reference. This has led to divergence on edge-cases for cookies within various browsers, servers, and other tools.

We’ve been working with browser, server, and web app folk in an IETF working group, “httpstate“, to rectify this, and the draft spec was recently approved for publication as an IETF RFC at the “Proposed Standard” maturity level. This spec differs from the prior specs in that it specifies how cookies are actually used on the Internet today. Anyone crafting a new client or server can implement the spec and have an interoperable implementation as a result.

This is great in that getting this finally explicitly documented will be a key underlying piece of moving “the Web“, and the wider Internet its built upon, on towards its next stage(s). Hopefully, browsers and servers can now converge their “cookie behaviors” :)

Our more detailed blog post (which includes some history) is here..

‘HTTP State Management Mechanism’ to Proposed Standard
http://www.thesecuritypractice.com/the_security_practice/2011/03/http-state-management-mechanism-to-proposed-standard.html

=JeffH sez check it out :)

Web (In)Security: Remediation Efforts - Status and Outlook

Monday, March 7th, 2011

We have a blog post over at my work cohort’s blog, w.r.t. a recent preso we gave, here’s the link…

Web (In)Security: Remediation Efforts - Status and Outlook
http://www.thesecuritypractice.com/the_security_practice/2011/03/web-insecurity-remediation-efforts-status-and-outlook.html

Check it out :)

of TLS/SSL Server Identity Checking

Tuesday, February 1st, 2011

[ Update (23-Apr-2011): This spec was published as RFC6125 on 30-Mar-2011. See also this more recent post. ]

Aside from HSTS, which I’ve written about here earlier, I’ve also been working on a specification for “TLS/SSL Server Identity Checking” along with Peter Saint-Andre.

The basic summary is: you have a DNS domain name identifying some application service (aka “a server”) you wish to connect to over TLS/SSL, e.g. “www.example.org”, and once you do so, how do you really know (and check) that the returned PKIX Certificate contains an identifier(s) that maps to the name of the application service you intended to interact with?

This turns out to be a fairly complex endeavor, and up to the present here, various protocol specs have either specified it on their own, or have referenced another spec that has addressed the problem. One such referenced spec is RFC2830, “Lightweight Directory Access Protocol (v3): Extension for Transport Layer Security“, which I co-authored. So anyway, I got involved a few years back in trying to concoct a dedicated specification for how to do TLS/SSL server identity checking in an application protocol neutral fashion. Eventually, Peter Saint-Andre and I signed up to buckle down and make the spec a reality. Much of this work occurred during 2010.

The resulting internet-draft, draft-saintandre-tls-server-id-check, was approved on 20-Jan-2011 as a Proposed Standard RFC, and will be published as such in the next couple of months. It has this fairly precise but unwieldy title:

Representation and Verification of Domain-Based Application Service Identity within Internet Public Key Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer Security (TLS)

In the spec (which has been referred to as “-tls-server-id-check” in various email discussion threads (e.g. see the certid@ietf.org list), we provide an appendix of extracts from various current RFCs that specify performing such a check. The hope is that, going forward, emerging specifications can simply reference (i.e. “re-use”), and profile if necessary, the -tls-server-id-check spec. In fact, there’s presently four Internet-Drafts in the RFC-Editor’s work queue that do just that.

=JeffH sez check it out :)

New rev of SIP-SAML profile

Tuesday, November 4th, 2008

There’s a new revision of the SIP-SAML profile spec..

SIP SAML Profile and Binding
http://www.ietf.org/internet-drafts/draft-ietf-sip-saml-05.txt

The key changes in this revision are that we’re aiming for experimental track (for now) due to a subtle-but-important impedance mismatch with the “SIP Identity” spec (RFC 4474, which we build upon), and we’ve add an additional profile to the spec. This new profile simply specifies SAML assertion conveyance “by value” in the body of SIP message(s) rather than “by reference”.

Note that the overall notion of “SIP Identity” has been in-flux over the last year+. Once that set of issues is (hopefully) resolved, then we can do another SIP-SAML spec on the standards track.

Also, the SIP WG co-chairs have called for Working Group Last Call on this -05 revision.

=JeffH sez getcher comments in!

A Passel of IETF Internet-Drafts Reference SAML

Wednesday, October 11th, 2006

I did a cursory analysis of the number of current (as of 4-Oct-2006) IETF Internet-Drafts (I-Ds) that reference or employ SAML, and to what extent they do so. The executive summary of my findings is (click here to skip intro):

SUBSTANTIVE SAML employment:     8   I-Ds
Some SAML Incorporation:        10    ''
SAML referenced 'in passing':   10    ''

Seems to me this is a non-trivial number and that SAML is acquiring some decent traction there.

My overall analysis write-up is here, it lists the I-Ds my simple grepping turned up, as well as the bits of text where the term SAML occurs.