DoH is working even if deactivated

[OniriCorpe]

Prerequisites

• [X] I have checked the Wiki and Discussions and found no answer

• [X] I have searched other issues and found no duplicates

• [X] I want to report a bug and not ask a question or ask for help

• [X] I have set up AdGuard Home correctly and configured clients to use it. (Use the Discussions for help with installing and configuring clients.)

Platform (OS and CPU architecture)

Linux, AMD64 (aka x86_64)

Installation

Custom package (OpenWrt, HomeAssistant, etc; please mention in the description)

Setup

On one machine

AdGuard Home version

0.107.48

Action

even when tls: enabled: false, the AGH server reply to DoH requests:

q example.com MX @https://adguard.example.com
example.com. 21h57m8s MX 0 .

full TLS config section:

tls:
  enabled: false
  server_name: adguard.example.com
  force_https: false
  port_https: 13120
  port_dns_over_tls: 853
  port_dns_over_quic: 784
  port_dnscrypt: 0
  dnscrypt_config_file: ""
  allow_unencrypted_doh: true
  certificate_chain: ""
  private_key: ""
  certificate_path: /etc/yunohost/certs/adguard.example.com/crt.pem
  private_key_path: /etc/yunohost/certs/adguard.example.com/key.pem
  strict_sni_check: false

Expected result

if tls: enabled: false, AGH should refuse any DoH requests, as stated in the interface:

Actual result

Instead of refusing the DoH request, AGH reply with the right answer

The setting is working properly for DoT and DoQ

Additional information and/or screenshots

The installation is using the YunoHost package I'm one of its maintainers, btw

[ainar-g]

Thanks for the report. This seems to be an unintended consequence of allow_unencrypted_doh: true. DoH on port 443 doesn't work, but on port 80 does.

[OniriCorpe]

just in case: the nginx config for the /dns-query path:

location /dns-query {
  proxy_set_header Host $host;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_bind 127.0.0.1;
  proxy_pass http://127.0.0.1:3002/dns-query;
}

[ainar-g]

On a second thought, I'm not sure whether this is an issue. Enabling the DoH server over plain HTTP is precisely what the setting is supposed to do. @OniriCorpe, what's the expected behavior here from your point of view? As in, why wasn't the connection between allow_unencrypted_doh and serving DNS over plain HTTP isn't obvious?

[tjharman]

Hi @OniriCorpe are you able to answer the query? Thanks!