W3C

Web Security Context Working Group Teleconference
24 Sep 2008

See also: IRC log

Attendees

Present
Mary Ellen Zurko, Thomas Roessler, Yngve Pettersen, Maritza Johnson, Jan Vidar Krey, Tyler Close, Rachna Dhamija, Bill Doyle, Dan Schutzer
Regrets
Ian Fette, Joe Steele, Anil Saldhana
Chair
Mary Ellen Zurko
Scribe
Tyler Close

Contents


Minutes approved

Pending Actions

mez: nothing that needs discussion in the telecon

<Mez> http://www.w3.org/2006/WSC/track/actions/open

Open Action items

Agenda Bashing

Mez: We will be looking at the comments from Vijay of the IETF applications area.
... Want to do more with the Features at Risk over the next couple of weeks.

<Mez> http://lists.w3.org/Archives/Public/public-wsc-wg/2008Sep/0019.html

Last call comments from Vijay

Mez: Thanks to Lisa for coordinating this feedback
... There's an RFC reference that needs to be corrected

TLR: on it!

Mez: There's an editorial comment in about the second paragraph

TLR: got that one too

<tlr> +1 to MEz

Mez: Vijay believes our interpretation of the AA-qualified certificate fields is incorrect
... Thought the use of the OID in the certificate was the correct mechanism

TLR: thinks this might be an issue with the clarity of the text
... will try to clarify

Mez: Looking at the question about the SAN field.

Yngve: There are requirements on what must be in these certificates

Mez: So we should specify that certificates that are missing required fields are not AA?

Yngve: Some close checking of the specification is needed here
... Need to check into the exact contents of the SubjectAltName

<tlr> ACTION: yngve to check EV expectations for subjectAltName [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action02]

<trackbot> Created ACTION-517 - Check EV expectations for subjectAltName [on Yngve Pettersen - due 2008-10-01].

Mez: Moving on to the comment on Section 5.1.5
... We didn't think we needed to specify a number of visits.
... Anyone have other opinions?
... OK, so no we don't think we need to specify a number of visits
... Moving on to section 5.1.6

TLR: Tyler has an ACTION here

tyler: Part of the response is the new petname rec text

Mez: Section 5.4.1

<Mez> http://www.w3.org/TR/wsc-ui/#sec-tlserrors

Mez: I think "these interactions" refers to interactions resulting from a TLS error
... I think part of the confusion comes from ambiguity about which certificates the comment is about

TLR: Yes, I think we need to clarify the text here.
... thinking...

<Mez> When certificate information is presented in these interactions, human-readable information derived from the certificates in question (and any other certificates not trusted) MUST NOT be presented as trustworthy. Examples of such certificate information within those certificates not to be presented as trustworthy include Common Name or Organization attributes.

<tlr> ACTION: thomas to refine text above this action in the minutes [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action03]

<trackbot> Created ACTION-518 - Refine text above this action in the minutes [on Thomas Roessler - due 2008-10-01].

Mez: Moving on to comment on Section 6.1.1

<Mez> http://www.w3.org/TR/wsc-ui/#identity-requirement

TLR: This is about IETF view that DNS names shouldn't be used in the CN field, although the Internet currently works that way.

<tlr> ... then it MUST include an applicable DNS name. The DNS name MUST be derived from a subjectAltName extension. If this extension is not present, and a DNS name is included with the certificate's Common Name attribute, then the latter MUST be used.

Yngve: Perhaps we should just reference the rules in HTTPS RFC, and so just say "according to the rules".

TLR: I fear it is actually specified in 2817
... the TLS upgrade spec

<tlr> http://www.ietf.org/rfc/rfc2818.txt

<tlr> RFC 2818 section 3.1

Yngve: RFC 2818 is informational
... its old

tyler: Think we don't want to reference any of the fields in the certificate, but use the hostname from the URL, as validated by the certificate. After all, there may be multiple hostnames in the certificate.

<tlr> *.w3.org -> w3.org if there's a wildcard?

rachna: What are we trying to convey to the user?
... do we want the user to know there is a wildcard certificate in use?

tlr: I am worried about a wildcard cert letting the attacker choose an arbitrary string to present to the user

tyler: Perhaps the base domain concept could be useful here.

tlr: Don't want to use that here
... For example, phisher has cert for *.foo.com and puts up a site at bankofamerica.foo.com
... Perhaps show the longest validated part of the hostname.
... which would be similar to the base domain concept

<Mez> cutting off the asterisk is a little odd

<Mez> .foo.com and foo.com look pretty similiar

<Mez> in the former case it's a "good" match, in the latter, it's not

TLR: prefers string transform to the base domain algorithm which uses a separate database

<tlr> "E.g., *.a.com matches foo.a.com but not bar.foo.a.com. f*.com matches foo.com but not bar.com."

<tlr> (from 2818)

Yngve: Opera shows the wildcard value from the certificate.

TLR: Let's also look at how the other browsers are handling this

Yngve: discussing the particulars of wildcard matching in PKIX

<tlr> ACTION: thomas to solicit input on wildcard implementation [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action04]

<trackbot> Created ACTION-519 - Solicit input on wildcard implementation [on Thomas Roessler - due 2008-10-01].

<tlr> ACTION: thomas to draft explanation of wildcard & scaling of attacks [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action05]

<trackbot> Created ACTION-520 - Draft explanation of wildcard & scaling of attacks [on Thomas Roessler - due 2008-10-01].

<tlr> ISSUE: What information should be shown in the identity signal if no human readable information except for domain names is available? (6.1.1, LC-2088)

<trackbot> Created ISSUE-216 - What information should be shown in the identity signal if no human readable information except for domain names is available? (6.1.1, LC-2088) ; please complete additional details at http://www.w3.org/2006/WSC/track/issues/216/edit .

Mez: Moving on to Section 7.1.1

<Mez> http://www.w3.org/TR/wsc-ui/#sharedsecret-goodpractice

Mez: I thought this whole section was about the user agent rather than the server. So am looking for the place where Vijay found the text about the server
... Ah I see in section 7.1.1 we talk about a site spoofing the browser

Yngve: Perhaps the first sentence should call out the motivation for having a trusted path.

<tlr> oooops, wasn't totally tuned in

<tlr> ACTION: mez to propose clarification for 7.1.1 [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action06]

<trackbot> Created ACTION-521 - Propose clarification for 7.1.1 [on Mary Ellen Zurko - due 2008-10-01].

Mez: Give me an ACTION to propose clearer text
... 6.1.1 looks like it requires the most thought, though the petnames comments may also
... What are the next steps.

TLR: We're still reviewing the comments. Will need to draft a response eventually.

<tlr> http://lists.w3.org/Archives/Public/public-usable-authentication/2008Sep/

Summary of Action Items

[NEW] ACTION: mez to propose clarification for 7.1.1 [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action06]
[NEW] ACTION: thomas to draft explanation of wildcard & scaling of attacks [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action05]
[NEW] ACTION: thomas to put information about upcoming f2f on group homepage [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action01]
[NEW] ACTION: thomas to refine text above this action in the minutes [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action03]
[NEW] ACTION: thomas to solicit input on wildcard implementation [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action04]
[NEW] ACTION: yngve to check EV expectations for subjectAltName [recorded in http://www.w3.org/2008/09/24-wsc-minutes.html#action02]
 
[End of minutes]