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Comment by tptacek | Hacker News Reader

Certificate pinning cannot stop this type of mass-surveillance. It is a band-aid that some companies use to mitigate the problem for their specific applications.

PKP is obviously a band-aid, and nobody involved with it says otherwise; it's a static list delivered with browsers. But the idea of pinning scales just fine and isn't simply a band-aid. The TACK proposal allows every site to assert their own pins, and does in fact largely mitigate the risks of compromised certificate authority.

https://tools.ietf.org/html/draft-perrin-tls-tack-02

It's disingenuous to argue that Google and Mozilla implement PKP simply to protect their own properties. They protect many properties other than their own.

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But Google and Mozilla aren't implementing TACK, are they?

The code exists for NSS. There are multiple CA mitigation technologies under consideration right now. CT seems to be the priority. Watch Chris Palmer's TrustyCon presentation for more details.

There are multiple CA mitigation technologies under consideration right now.

Do these "mitigation technologies" require us to continue paying CAs protection money? From what I read about TACK, it seems like it doesn't require that, but what's actually being done?

"Protection money" meaning paying for them to run a CA infrastructure, handle audits, and verify identity as per requirements? (Admittedly, "domain control" verification is sorta useless and completely automated.) Are HSMs and all these people supposed to just be paid on goodwill?

Not that some CAs aren't overpriced, but calling it "protection money" is just silly. You're free to go use your own CA. Once you've got it all setup and meet criteria, I'm sure Mozilla and others will let you in.

It's protection money, no way to sugar coat it.

It's not necessary, at all.

An untrusted cert looks identical to an attack. So the CA, while perhaps a circus, is necessary with current technology. Without that, there's no way to determine if you've been MITM'd or not - that's like the whole point of using TLS.

I know there are other proposals, but within the current constraints of the "global PKI", there's no alternative.

On a side note, for an EV cert, the CA must verify the registrant of the domain. They usually do a phone call to verify a phone number matching some other record with the name of the registrant. That takes some human effort to verify; more than an automated email. (In addition to just running a company, keeping a CA online but secure, etc.)

So the CA, while perhaps a circus, is necessary with current technology.

With current technology, it is not necessary.

Because of the blockchain (current tech) they serve absolutely no useful purpose.

You cannot claim that because web browsers voluntarily choose not to use it that it somehow disqualifies it as current tech.

Same goes for the EV cert and phone calls and all that jazz. Simply not necessary, and adds no extra value. In fact, it makes all of us less secure as the article points out.

If, to take one of my favorite companies as an example, Mozilla were to support the blockchain for authentication, they would register themselves there, and that's that. No phone calls necessary, they simply own their identity, and can, via established existing channels (@mozilla twitter account, their newsletter, their .com, etc.) declare what is and isn't official.

They can even get their .com into the blockchain, although that isn't yet current tech:

http://forum.namecoin.info/viewtopic.php?f=5&t=1439

It's just protection money. No regular user actually cares about EV certs. The lowest thing that passes validation (domain validated certs) is fine and that's trivially automated.

The exorbitant fees are a joke that don't result in any improved security for the end user.

I'm not so sure about that, the way the browser vendors and companies beat it into their user's heads to look for the green bar with the company name on it.

Granted, it's still a scam. "Pay us money or all your customer's browsers will get scary and misleading error messages!"

The browser message is not misleading. A untrusted cert is indistinguishable from a MiTM attack.

and 99.99999999% of the time, a self signed cert represents... not much of anything, other than the fact that a site owner declined the to pay the PKI racket's protection money.

And even if we ignore that, the whole "EV Cert" thing is a total sham. All the EV cert does is indicate that you overpaid for it.

> It's disingenuous to argue that Google and Mozilla implement PKP simply to protect their own properties.

The post didn't name specific companies or products, but on that note, is there a list of sites that Chrome and/or Firefox have pinned somewhere? I don't think TACK has been implemented in them.

The thing with TACK is that it doesn't actually solve the key distribution problem. The draft itself states:

   TACK pins are easily shared between clients.  For example, a TACK
   client may scan the internet to discover TACK pins, then publish
   these pins through some 3rd-party trust infrastructure for other
   clients to rely upon.

Keywords: "some 3rd-party trust infrastructure"

That is what DNSChain and the blockchain provides. It provides more than that though, and thus providing everything that TACK proposes too.

This is a misrepresentation of TACK. TACK will ordinarily be deployed similarly to HSTS: it's a key continuity scheme, like SSH. It doesn't require a "third party trust infrastructure". But unlike the CA system, TACK also supports the notion of a third-party root; the EFF could run a site that would provide trustworthy pinned keys for arbitrary sites on the Internet, and you could subscribe to that site.

Contrast to DNSChain, which requires that ordinary users trust a third-party server.

DNSChain isn't going to happen.

the EFF could run a site that would provide trustworthy pinned keys for arbitrary sites on the Internet, and you could subscribe to that site.

So how do you know that your subscription to EFF is secure?

Contrast to DNSChain, which requires that ordinary users trust a third-party server.

First-party, not third-party. What you described with EFF is a third-party, whereas DNSChain is a first (or 2nd) party, because either you own the server (1st party), or your friend does (2nd? party).

DNSChain isn't going to happen.

It's already happened. I'm using it right now. Where's TACK?

You're playing semantic games with "first party" and "second party" and "third party".

If I didn't think EFF was trustworthy, I wouldn't subscribe. Key continuity would still make TACK valuable; even without trusted third parties, widespread deployment of TACK would practically eradicate dragnet surveillance through compromised CAs, because every attempt to forge a certificate would quickly be detected.

You're playing semantic games

I am not. Those words have real meaning that doesn't disappear when you accuse me of playing semantic games.

If I didn't think EFF was trustworthy, I wouldn't subscribe.

I asked how do you _know_?

With DNSChain, you actually have a great deal of certainty that is based on math, not public reputation.

widespread deployment of TACK would practically eradicate dragnet surveillance through compromised CAs, because every attempt to forge a certificate would quickly be detected.

With DNSChain there are no compromised CAs to eradicate, and therefore no problem. You also get to keep your money, no more need to pay for SSL certificates.

Ok, you have fun with that.

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