- From: Matt DeMoss <demoss.matt@gmail.com>
- Date: Fri, 24 Jun 2011 16:45:46 -0400
- To: Henry Story <henry.story@bblfish.net>
- Cc: Kingsley Idehen <kidehen@openlinksw.com>, public-xg-webid@w3.org
>Its spec concepttually little or no different to using a directory object from ldap, looking for existance of a cert value in the directory attribute.. >that is why I distinguish - and we should distinguish more clearly in the spec - between a claimed WebID and a verified one. A WebID presented in the SAN fields of an X509 certificate is a claimed WebID. The Relying Party/IDP then fetches the canonical document for each WebID I find the contrast with a directory object to be particularly interesting. It's usually the case that the CA is trusted to sign a DN that corresponds to a directory object in a directory we trust to have the correct attributes, but I would be interested to know more about other systems where (as with WebID) the trust relationship is a bit different. Do any of the SAML profiles do something you would consider comparable? On Fri, Jun 24, 2011 at 4:31 PM, Henry Story <henry.story@bblfish.net> wrote: > > On 24 Jun 2011, at 22:00, Kingsley Idehen wrote: > > On 6/24/11 7:08 PM, Peter Williams wrote: > > The defacto owl sameAs part is really interesting (and its the semweb part > of webid that most interests me, since its about the potential logic of > enforcement....) > > are we saying that should n URIs be present in a cert and one of them > validates to the satisfaction of the verifying party, then this combination > of events is the statement: verifer says owl:sameAs x, where x is each > member of the set of SAN URIs in the cert, whether or not all x were > verified . > > No. > > When an IdP is presented with a Cert, it is going to have its own heuristic > for picking one WebID. Now, when there are several to choose from I would > expect that any choice results in a path to a Public Key -> WebID match. > Basically, inference such as owl:sameAs would occur within the realm of the > IdP that verifiers a WebID. Such inference cannot be based on the existence > of multiple URIs serving as WebIDs in SAN (or anywhere else). > > Yes, that is why I distinguish - and we should distinguish more clearly in > the spec - between a claimed WebID and a verified one. A WebID presented in > the SAN fields of an X509 certificate is a claimed WebID. > The Relying Party/IDP then fetches the canonical document for each WebID. > These documents define the meaning of the WebID, of that URI, via a > definitive description tying the URI to knowledge of the private key of the > public key published in the certificate. > If the meaning of two or more URIs is tied to knowledge of the same public > key, then the relying agent has proven of each of these URIs that its > referent is the agent at the end of the https connection. Since that is one > agent, the two URIs refer to the same thing. > > > > > Thats quite a claim to make. An more restrcitied claim could be that > > Yes, but I don't believe the spec infers that. > > > verifier says webid says owl:sameAs x, where x is each member of the set of > SAN URIs in the cert, whether or not all x were verified . > > No, don't think that's the implication from spec or what one would expect to > happen. > > Kingsley > > > ________________________________ > From: henry.story@bblfish.net > Date: Fri, 24 Jun 2011 19:12:59 +0200 > CC: public-xg-webid@w3.org; foaf-protocols@lists.foaf-project.org > To: home_pw@msn.com > Subject: Re: [foaf-protocols] WebID test suite > > > On 24 Jun 2011, at 18:45, Peter Williams wrote: > > one thing the spec does not state is what is correct behaviour when a > consumer is prersented with a cert with multiple SAN URIs. > > Well it does say something, even if perhaps not in the best way. It says: > in 3.1.4 > "The Verification Agent must attempt to verify the public key information > associated with at least one of the claimed WebID URIs. The Verification > Agent may attempt to verify more than one claimed WebID URI." > then in 3.1.7 > If the public key in the Identification Certificate matches one in the set > given by the profile document graph given above then the Verification > Agentknows that the Identification Agent is indeed identified by the WebID > URI. > I think the language that was going to be used for this was the language of > "Claimed WebIDs" - the SANs in the certificate, which each get verified. The > verified WebIDs are the ones the server can use to identify the user. They > are de-facto owl:sameAs each other. > > If the test suite is run at site A (that cannot connect to a particular part > of the interent, becuase of proxy rules) presumably the test suite would > provide a different result to another site which can perform an act of > de-referencing. > > That is ok, the server would state declaratively which WebIDs were claimed > and which were verified. It could state why it could not verify one of the > WebIDs. Network problems is a fact of life, less likely than strikes in > France - though those have been not been happening that often recently - or > congestions on the road. > > > This is a general issue. The degenrate case occurs for 1 SAN URI, obviously > - since siteA may not be able to connect to its agent. Thus, the issue of 1 > or more multiple URIs is perhaps not the essential requirement at issue. > > A variation of the topic occurs when a given site (B say) is using a caching > proxy, that returns a cached copy of a webid document (even though that > document may have been removed from the web). This is the topic of trusted > caches, upon which it seems that webid depends. > > That is what the meta testing agent will be able to tell. He will be able to > put up WebID profiles log in somewhere, then login a few days later after > having removed the profile, or changed it and report on how the servers > respond. > > We would look silly if the average site grants access to a resource when > the identity document has been removed from the web, > > It all depends on what the cache control statements on the WebID Profile > says. If they state they should last a year, then it is partly the fault of > the WebID profile publisher. (Could Web Servers offer buttons to their users > to update a cache?) > In any case it also depends on how serious the transaction is. In a serious > transaction it might be worth doing a quick check right before the > transaction, just in case. > > yet cache continue to make consuemr believe that the identity is valid. At > the same time, given the comments from the US identity conference (that > pinging the internet during a de-referencing act is probably > unsunstainable), caches seem to be required (so consuming sites dont > generate observable network activity). > > WebID works with caches. I don't think we could think without. Even X509 > works with caches as is, since really an X509 signed cert is just a cache of > the one offered by the CA. > > This all seems to be pointing at the issue that we have a trusted cache > issue at the heart of the webid proposal, and of course we all know that the > general web is supposed to be a (semi-trusted at best) cache. > > Caches need to be taken into account. But I don't see this as a major > problem. > > > > > >> From: henry.story@bblfish.net >> Date: Fri, 24 Jun 2011 13:37:26 +0200 >> CC: foaf-protocols@lists.foaf-project.org >> To: public-xg-webid@w3.org >> Subject: WebID test suite >> >> Hi, >> >> In the spirit of test driven development, and in order to increate the >> rate at which we can evolve WebID, we need to develop test suites and >> reports based on those test suites. >> >> I put up a wiki page describing where we are now, where we want to go. >> >> http://www.w3.org/2005/Incubator/webid/wiki/Test_Suite# >> >> Please don't hesitate to improve it, and place your own library test end >> points up there - even if they >> are only human readable. >> >> The next thing is to look at the EARL ontology I wrote and see if your >> library can also generate a test report, that folows the lead of the one I >> put up on bblfish.net. I expect a lot of detailed criticism, because I did >> just hack this together. As others implement their test reports, and as >> bergi builds his meta tests we will quickly notice our disagreements, and so >> be able to discuss them, and put the results into the spec. >> >> Henry >> >> Social Web Architect >> http://bblfish.net/ >> >> > _______________________________________________ > foaf-protocols mailing list > foaf-protocols@lists.foaf-project.org > http://lists.foaf-project.org/mailman/listinfo/foaf-protocols > > Social Web Architect > http://bblfish.net/ > > > -- > > Regards, > > Kingsley Idehen > President & CEO > OpenLink Software > Web: http://www.openlinksw.com > Weblog: http://www.openlinksw.com/blog/~kidehen > Twitter/Identi.ca: kidehen > > > > > > Social Web Architect > http://bblfish.net/ >
Received on Sunday, 26 June 2011 12:37:38 UTC