Concerns over DNS Blocking

Hirom@beehaw.org to Technology@beehaw.org – 31 points –
medium.com

"Concerns over DNS Blocking" by Vinton Cerf

23

PiHole with upstream dns-over-tls or dns-over-https.

Anybody who wants to can get around DNS blocks. Sure it'll stop Aunt Sally, but anyone who cares will get around it. It's a really dumb way of doing things.

Well our government likes doing dumb things. That is kind of their platform lately.

As as US idiot, it feels good to have been right about how much of a corpo scumfuck Macron is.

We knew. Well, at least some of us did. Why call yourself an idiot though ?

It’s trivial for me to detect and block dns over https with modern firewalls.

How? I don't see what could find dns-over-https in the middle of other https traffic?

there is a lot more to modern firewall app detection than ports. My Palo Alto has a specific category to detect and block dns over https.

Even Palo Alto notes that they can only effectively block DoH if you're MITMing all https traffic already (e.g. using a root certificate on corporate-managed devices). If not able to MITM the connection, it will still try to block popular DoH providers, though.

https://live.paloaltonetworks.com/t5/blogs/protecting-organizations-in-a-world-of-doh-and-dot/ba-p/313171

For rather cheap I can see what traffic is suspicious. If you throw more resources at the problem and scale up it becomes simple to see traffic that looks like dns over https without having to decrypt it. Indicators such as size, frequency, consistent traffic going from your host to your DoH provider and then traffic going to other parts of the internet….these patterns become easy to establish. Once you have a good idea that a host on the internet is a DoH provider you can drop it into that category and block it.

Fair enough. Doesn't bode well for DoH in authoritarian regimes.

Port number is pretty indicative of DNS traffic, if we're talking IPv4.

French people really like to protest, so maybe we can teach them all to set up their own DNS resolvers with Raspberry Pis?

It would be a really, really difficult law to police if individuals were all managing their own DNS resolvers.

Sure we do, but you cannot expect everyone to simply run their own DNS and call it a day.

The vast majority of people don't even know that DNS even exist, let alone that your ISP can monitor/alter your traffic through it.

I'll admit, it's a much less "exciting" way to protest than flipping cop cars and starting fires.

And eventually they'll just ban personal DNS resolvers and force you to do the latter anyways.

Technology cannot fix bad government/politics.

I'm out of the loop, what is France trying to do with regard to DNS?

Government-mandated DNS blocklists.

As much as I dislike wasteful cryptography, this seems like an really good use case for cryptographically signed and owned names. Kind of like ENS domain names.

That way no single third party you can remove you from the internet effectively

demand non-identifying traffic data from electronic communications operators on-demand

I'm not sure what this means. Almost all traffic data identifies someone, whether it's the customer or their destination. I'm assuming they just don't care about the latter, but it's still identifying information.

I swear there was just a case of a German judge doing exactly what they're worried about in the article, though, telling a DNS resolver that they had to censor a site from the whole internet to comply with their law.