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> DNSSEC secures server-to-server DNS lookups, not the client-to-server lookups that your browser generates. That is just an implementation detail is it not? M
by magila 11y ago
> DNSSEC secures server-to-server DNS lookups, not the client-to-server lookups that your browser generates.
That is just an implementation detail is it not? My understanding is that there is nothing stopping a user (or more likely, the suppler of the user's OS) from setting up a local DNS server which verifies DNSSEC records.
> its real use case, that of replacing the CAs with DNS TLD operators, has the net effect of signing Internet cryptographic trust over to the world governments that control the most important TLDs.
Those governments can already get fraudulent certs issued to them either by directly coercing a CA located within their jurisdiction, exploiting a vulnerability in one of the hundreds of CAs worldwide, or by temporarily falsifying the records of the target domain to trick an unsuspecting CA. The difference with DNSSEC+DANE is that governments can only impersonate domains under TLDs that they control. No longer can Iran impersonate google.com by hacking a Belgium CA.
I'm not going to defend all of the implementation details of DNSSEC. Suffice to say, mistakes were made, but the concept is sound.
- tptacek 11y ago(a) Users are actively discouraged against setting up full resolvers on their desktops, (b) browser vendors (at least at Apple, Mozilla, and Google) had experimental support for DNSSEC that has now been withdrawn, (c) if we get to stipulate that end-users will install additional security software of our choosing, we can do way better than DNSSEC! So no, I don't concede that this is simply an "implementation detail". Governments can't simply subvert CAs anymore, because of key pinning. If they do that, there's a very good chance they'll get caught, and when they get caught their CA gets restrictions imposed by the browser vendors, or removed altogether. There are no meaningful consequences for the hard-to-detect forgeries DNSSEC enables NSA/GCHQ to make. Google can't simply restrict .COM, or switch to another domain. Google Mail just has to live with the security/privacy policies of all the TLDs it operates on, forever, with no recourse. That's a terribly unsound concept.
- throwaway2048 11y agoHypotheticly, lets say an intelligence agency/whoever keeps hijacking domains and then getting CAs to issue certs for them. The CA cannot automatically detect when a domain has been hijacked, it will issue the certs. In this situation (with either the present DNS world, or dnscrypt), agencies are frankly 100% as unaccountable as they would be under DNSSEC world, because they still control the TLDs. DNSCrypt does as little as DNSSEC to fix this issue. Pinning and certificate transparency can help detect under either scenario however. Another concern in DNSCrypt is how does it handle the MITM problem between DNS servers? Trust on first sight is a lousy unscalable model (what if keys change, what if the badguys are already there before first contact) that is way more vulnerable than DNSSEC to forged replies.
- tptacek 11y agoWhile I don't agree with the particulars, I am not in fact a DNSCrypt advocate. I think the right next step for DNS security is "do nothing".
- throwaway2048 11y agoThe problem of "asshole controls the TLD" is not solvable via ANY protocol. That dosen't mean DNSSEC is worthless, or handing over the keys of the internet to the government or miscellaneous hyperventilating. You are falling into the classic trap of "this dosent solve every problem so we cannot permit it to solve any problem" that has held back security for decades. DNSSEC is real, it is deployable and stuff is capable of supporting it, and it does solve very real issues. That counts.
- tptacek 11y agoSorry, that's simply not true. Assholes control TLDs today, and they do not get to easily bypass Gmail TLS. My point is, of course, that DNSSEC creates more serious problems than it solves. If you think my argument is "DNSSEC isn't perfect and we should wait for perfection", you haven't read what I'm saying carefully enough.
- magila 11y agoKey pinning is not a panacea either, it just makes browser/OS vendors another authority to be compromised and subverted. While a healthy dose of cynicism is appropriate with-respect-to government control of TLDs, in the western world they are still at least nominally accountable to their constituents. Wholesale forgery is not likely to go over well with them, most importantly not with large tech companies. Targeted one-off forgeries would be easier to get away with, but they are also still perfectly doable today.
- tptacek 11y agoThat's a hand-waving argument. It basically says there's not much point in being concerned about communications security because someone who owns up your endpoint can bypass it anyways.