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Re:72% of smart TVs and 46% of game consoles hardcode DNS se... by mindslight on Saturday December 05, 2020 @12:36PM (#25316400)
Your technical description doesn't really respond to the meat of the critique of DoH, which is that it prevents the technique described in this article - transparent proxying for all traffic of a certain service, in this case DNS.

The problem is that your relationship with your network devices is logically the same as a totalitarian country's/company's relationship with their citizens/users. So any protocol that prevents censorship/surveillance by ISPs also impinges upon bona fide network administrators. Corporate networks have the same dynamic, although there are few tears shed when it becomes harder for them to tamper with users' traffic.

The right answer is to make sure devices that have any Internet access run code you control. The root of the problem here is buying a "smart" TV, hooking it up to the network, and then expecting to tame all of its user-hostile anti-features by policing its communication. The only way to use black box IoT devices is to remove all general Internet access from them, allowing communication only with hosts you do control. For instance I've got a network of tp-link bulbs that are all controlled from a Home Assistant instance, and they never have and never will get a packet out to the larger Internet.

Re:72% of smart TVs and 46% of game consoles hardcode DNS se... by acdha on Saturday December 05, 2020 @01:06PM (#25316719)
My point was simply that DNS was never an effective measure. Corporate operators don’t need it since they can configure proxies and install endpoint monitoring, but the people building untrustworthy IoT devices or malware can’t be relied upon to cooperate.

I agree that the core problem here is blocking egress entirely – and that’d be a good area for home routers to add UI polish so you could easily allow your TV to hit Samsung.com if there’s an update you need before turning it back off. Unfortunately that’s going to be a losing game for many devices and that really hits at the root cause: we need strong regulation controlling privacy because trying to stop a well-funded company with purely technical measures is almost always a losing game.

Re:72% of smart TVs and 46% of game consoles hardcode DNS se... by mindslight on Saturday December 05, 2020 @02:02PM (#25317269)
Well DNS has been a pragmatic measure for quite some time. I've definitely seen jailbreaks of embedded devices that start off by MITMing DNS to proxy all traffic. DoH is changing that, and I can see how that's annoying.

> hit Samsung.com if there’s an update you need

Why would you need an update? Updates are mainly necessary for security, which you don't need if the device isn't on the Internet. If the device doesn't have all the features you expect out of the box, return it within the return period. There's a small corner case where an update could carry significantly increased functionality, but it seems easier to ad-hoc address that down the line rather than plan for it. Carelessly doing updates is a good way to break your device.

> Unfortunately that’s going to be a losing game for many devices

I don't see how it's a losing game if you play it correctly. Fine grained policing of types of traffic is a losing game, but wholesale denying transit isn't. There is little difference between my network of tp-link bulbs and a local modbus network.

Re:72% of smart TVs and 46% of game consoles hardcode DNS se... by acdha on Saturday December 05, 2020 @02:32PM (#25317556)
> Why would you need an update? Updates are mainly necessary for security, which you don't need if the device isn't on the Internet.

You've never had a problem which was fixed by an update or something which added support for, say, a new model peripheral? I have, which is why I allowed for the possibility of wanting to do this on the schedule of your choosing but not the default case.

> I don't see how it's a losing game if you play it correctly. Fine grained policing of types of traffic is a losing game, but wholesale denying transit isn't. There is little difference between my network of tp-link bulbs and say a local modbus network.

I was thinking less narrowly than devices which never need to be online. A TV connected to other players can run entirely offline but there are many other things which legitimately need connectivity and there's no good way to prevent that. For example, think about a device like a Chromecast or Fire TV, or those Facebook video chat appliances — people buy those to stream content so the most you can do is force the vendor to send marketing stuff through the same endpoint they use for your content, and that's increasingly hard to filter (think how useful a “it goes to an IP in AWS. Block y/n?” prompt is). That's why I said it'll require a legal fix since a large fraction of the most invasive devices either already do or could trivially be modified to mix other data in with the traffic needed to function.

Re:72% of smart TVs and 46% of game consoles hardcode DNS se... by mindslight on Saturday December 05, 2020 @03:12PM (#25317861)
> You've never had a problem which was fixed by an update or something which added support for, say, a new model peripheral

For embedded devices? No. I can imagine it happening in general, but I don't think I would ever buy into a proprietary ecosystem so hard that there would be peripherals, and newly released ones at that. Still I would be cautious about doing said updates, lest they ruin the device I already have. Like I've got a newer Marantz receiver that works great and hasn't seen the Internet in several years. Even if they developed some new desirable feature, why would I want to let it reflash itself and possibly break, or even just get slower (software bloat)? I'd rather just continue using it as I bought it.

> there are many other things which legitimately need connectivity and there's no good way to prevent that

I sort things into categories. A TV would be in the category of "wtf would you ever hook that up online" - Internet access can only enable anti-features. A Chromecast is a different category - single purpose disposable device that if it turns into shit you just throw it out. Ads and surveillance are part of its price, and if your goal is to avoid them, you should just setup a Kodi box and call it a day.

Legally I don't really see what you're getting at here. I can see a law for my TV category, but leaving it disconnected or pulling the 5G modem will also solve that. How would you even begin to solve the Chromecast problem with a law? Maybe in the EU you could convince them to mandate unbundling ads from a service, but in the US exploiting consumers by shoving ads at them is one of the most popular business models. I don't see that ever changing via the legal system.