[mjg59]

You're moving the goalposts to a ridiculous degree. Chrome will be incredibly angry at you if you haven't updated in 70 days. How will a smart TV behave? I've no idea. It's probably not paying any attention to dnssec (otherwise pihole and co wouldn't work), so I don't think you're presenting a credible alternative.

[matthew9219]

That's just not what's happening. Reread the conversation. I started from here:

> Certificate transparency is cool, but it's not clear it really works for many classes of devices

Smart TVs aren't some gotcha I'm throwing in at the end. It's literally the first thing I said about CT. CT works ok for mobile phones, laptops, and other devices where you can make certain assumptions about multiple networks and frequent updates. If you want a technology that doesn't require these assumptions, you want DNSSec.

[mjg59]

Once you've got a 70 day old browser you're just waiting for it to hit one domain you can MITM or serve content from and then you've got arbitrary code execution and who cares whether dnssec is involved or not. Attacking CT is just not the threat model to be concerned about.

[matthew9219]

The example I gave was a router or gaming system updating itself (e.g. using CUrl) not a full browser. Don't strawman please - if my argument is as weak as you say, you shouldn't need to.

I want a version of Web PKI strong enough that I can turn off my tablet for a year, turn it back on in a coffee shop, apply automatic updates, and not have my web traffic monitored, even if I'm gay and the coffee shop is in Saudi Arabia.

From what I can see, DNSSec+CAA+.com+US CA+US hosting for the Android update server does the trick. No version of CT does.

[mjg59]

The Play Store has cert pinning, so this all works just fine in the scenario you're describing.

[matthew9219]

Web PKI so strong that we recommend not using it for critical scenarios.. /s

It's late and I maybe haven't been super constructive here, but I think when you try to write out the actual assumptions behind CT as the whole solution, you realize you've got something that mostly works assuming assuming assuming - and worse, we'll never do any better, because those assumptions are fundamental technical limits. DNSSec may be ugly but at least its problems (like validators failing open) are just deployment issues, not fundamental technical issues.

I'm sick and tired of using technologies that provide security or correctness subject to a long list of preconditions and ways for folks to tell me I'm using it wrong. To build secure systems, we need technology that provides correct security without so much asterisks and fine print.

[tptacek]

The whole premise of your argument about set-top boxes and CT was refuted, and you've used that as evidence that you were right all along.