- From: peter williams <home_pw@msn.com>
- Date: Mon, 11 Apr 2011 09:09:49 -0700
- To: "Kingsley Idehen" <kidehen@openlinksw.com>
- CC: "'WebID XG'" <public-xg-webid@w3.org>
- Message-ID: <SNT143-ds12124A61B0B5BCB3A499E592A80@phx.gbl>
One of the arguments I hear, is that CAs can be made irrelevant when the DNS naming authority takes on the role of binding a name to a key. This will help webid, therefore - getting things beyond the assurance limits being encountered today as browser-based trust anchoring systems show their age, under the scale that https is used today. Poor arguments are made to support this point (based on conventions like: CAs and trust anchoring as seen in browsers can only be used in the piss-poor manner of today, and IETF's PKIX specified constraints don't work). The poor arguments fail to take into consideration that things are piss-poor because of the quality of implementation and level of profile interoperability testing, by unmotivated vendors. Constraints don't "work" mostly, because half the browser just don't implement them. This is a world in which one fails the exam by not turning up to the testing center before the door closes. Poor rhetoricians then blame the exam system, itself! In Webid land, I see a political compromise coming about, in this space. But, something has to give, as always. First, I don't mind DNSsec (or stuffing an old DER-encoded self-signed cert in an RR, so DNSsec countersigns the blob). Its just a counter-signature scheme, like 10 others. What I mind is the impact on resilience, survivability, and control - if one centralizes the counter-signing apparatus. One simply has to shout "wikileaks" - to remember what happens when the DNS is manipulated by powers that be. Things disappear, globally (until the resilience features are properly used). With CAs being offline from naming authorities and DNS, this doesnt happen with X.509 certs - BY DESIGN. Obviously, some national security authorities (working on 1960s assumptions about who should have crypto) would like certs to disappear from the public space, just like DNS records. If we endorse counter-signing by DNS, we need a political re-balancing - to disrupt the downsides of DNS on resilience metrics. I like what Kingsley your group is doing, in allowing resolvable webids of the form "https://uriburner.com/?uri=<webid>. This indirection allows uriburner to resolve the authority in the https URI, within <webid>. uriburner may not bother with the DNS or DNSsec as the basis for testing the name. It may use its own replicated store of domain-name -> Ip address mappings. It's a counter-signing authority, perhaps using the counter-signatures of DNSsec but deciding for itself when (and when not) to project forward the naming authorities opinion to the consumer. I can see webid resolvers working with a world of DNSsec and specifically not DNSsec - to retain survivability elements from the CA world design for commodity-class browsers. I can imagine queries I issue, as webid consuming resource server, that ask: tell me how the webid validates in several validation models: (i) the assumption that DNSsec is authoritative for domain-names, and (ii) tell me under non DNS-Sec assumptions about the authoritiveness of domain-names. One might be tempted to say: well doesn't that centralize validation (using n scheme) in the uriburners of the world- thus centralizing (and making them easy subversion points, impacting huge populations a la wikileaks)? Yes! until we recall that our self-signed certs have multiple SANs, enabling the consuming relying party to be hint-directed to multiple uriburners. Assuming some independence of these validation authorities, it makes it hard to subvert all of them, on a subversion directed at a particular record (a la wikileaks, and US orders on DNS providers). This means giving up (for https webid) the notion that "only" direct URIs are proper. We have to legitimatize proxy naming of webids, so as to re-balance the downsides of DNS and DNSsec concerning the wider goals of survivability, resilience and provider autonomy, that motivated the design of the current browser-based CA system for name/key bindings (and despite all the whining, works very well).
Received on Monday, 11 April 2011 16:10:22 UTC