Support native DoH on Android 13

Google has started the rollout of native DoH to Android 13.

DoH is now on by default.

It will require Google Play to push the mainline module to the Android 13 devices as a staged rollout.

At the bottom of this article it shows that some addressing doesn't work whereas Google and Cloudflares addressing does.

Something to note is that Android 13 seems to favour DoH over DoT.

As an example, Google's dns.google which is both their DoT and DoH address will resolve as DoH and not DoT, as tested by a user on Telegram.
Given this, I'm not sure how a user would select DoT if they wanted to as the dev docs haven't been updated to reflect the changes yet.

AdGuard's public DoH addresses currently do not get accepted by Android 13, and if AdGuard DNS 2 is used, it defaults to DoT.

As Android has taken the choice out of whether DoT is preferred over DoH, it might be worth looking into differentiating the DoT and DoH addressing somehow to be accepted on Android 13.

User reporting issue: https://t.me/AlZullino

[ameshkov]

Android only enables DoH3 for a predefined list of DNS resolvers:
https://security.googleblog.com/2022/07/dns-over-http3-in-android.html#fnref2

Android devices from Android 11 onwards1 will use DoH3 instead of DoT for well-known2 DNS servers which support it

At this moment the list consists of Cloudflare DNS and Google DNS.

Tbh, we don't want to be on that list. At this point DoH3 support on our side is experimental and we're not ready to all Android devices switching to DoH3.

I'm referring to DoH support, not support for DoH3 (I know that's the flavour of the day at the moment :)).
The article only refers to HTTP or HTTP/2.

[ameshkov]

To my knowledge they didn't implement HTTP/2 :). What they refer as doh is actually doh3.

What a shame!
Ah well, back to my box.

Maybe this will be a future thing someday. :)