DNS over HTTPS servers

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Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: While this article currently focuses on python-doh-proxyAUR for the DoH proxy with bind for the DNS server and stunnel for the DoT implementation, the general setup is the same whichever software you choose to use. Stubs have been added and it is my hope that the other package maintainers will contribute for their preferred software. Additionally, the flow of this article is a bit confusing and I will be providing some clean-up (beyond the initial commit) to describe the various configurations in more detail. (Discuss in Talk:DNS over HTTPS servers#)

DNS, since its inception, has been unencrypted on UDP/53, and later TCP/53, making it susceptible to snooping attacks. For additional information on the available protocols that can be used to address this vulnerability, see Domain name resolution#Privacy and security. This article covers two of the three available protocols for DNS servers with the necessary proxy configuration to provide both DNS over HTTPS (DoH) and DNS over TLS (DoT). Multiple DoH utilities are available in the AUR including corednsAUR, dns-over-https, doh-proxyAUR, and python-doh-proxyAUR. Which of the available solutions is appropriate, depends on the needs of your network.

corednsAUR provides both a caching, non-authoritative DNS server, and DoH services (citation needed).

dns-over-https, doh-proxyAUR, and python-doh-proxyAUR all provide an HTTP listener for proxying behind your existing HTTPS server, and a stub resolver to forward regular queries on UDP/53 to a secure DNS server. Additionally, both doh-proxyAUR and python-doh-proxyAUR provide a standalone HTTPS/2 server.

DoH server/proxy software configuration

coreDNS

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Reason: please use the first argument of the template to provide a brief explanation. (Discuss in Talk:DNS over HTTPS servers#)

dns-over-https

Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: please use the first argument of the template to provide a brief explanation. (Discuss in Talk:DNS over HTTPS servers#)

doh-proxy

Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: please use the first argument of the template to provide a brief explanation. (Discuss in Talk:DNS over HTTPS servers#)

python-doh-proxy

Install the following packages: python-requests_downloadAUR; install-wheel-scriptsAUR; python-flit; and python-doh-proxyAUR.

Stub resolver

If you intend to provide encrypted queries to your local network for legacy applications, configure the stub resolver:

/etc/conf.d/doh-stub
LISTENPORT=5353
ADDR=127.0.0.1
DOMAIN=mydomain.tld
NS=127.0.0.1
PORT=443

If you do not have a way to provide a secure forward DNS lookoup to your real DNS server, you should configure both DOMAIN and NS to use one of the upstream providers (CloudFlare, OpenDNS, etc., instead of localhost). If you only need to provide lookups to localhost, this is fine. If you need to provide them for the entire network, the you could listen on 53 directly if you do not have a local caching or authoritative DNS server - you would also want to use the real IP address instead of the loopback adapter in this case.

DoH proxy

If you have an existing HTTP server and wish to proxy DNS lookups with it, setup the HTTP proxy to listen on port 8080:

/etc/conf.d/doh-httpproxy
NS=127.0.0.1
PORT=8080
ADDR=127.0.0.1

Optionally, you can utilize either the doh-proxy service or an upstream DoH provider to forward queries.

DoH proxy

If you do not have an existing http server, you can configure the HTTPS/2 lisener:

/etc/conf.d/doh-proxy
NS=127.0.0.1
UPSTREAMPORT=5353
ADDR=127.0.0.1
LISTENPORT=443
CERT=/etc/ssl/private/fullchain.pem
KEY=/etc/ssl/private/privkey.pem

Again, adjust as necessary, but be certain that the upstream server has a way to perform secure queries, or you will be creating a loop.

Standalone DNS server configuration

Bind

Typical: If using ISC bind as the current DNS provider, and you will be providing both forwarding services for legacy clients and DoH to modern clients, you will likely want to configure named to forward all non-local queries to your stub resolver, comment out any forwarding lines an forward to the stub resolver (omit forward only if you would like to fall back to roots):

/etc/named.conf
options {
...
    //forwarders { 8.8.8.8; 8.8.4.4; };
    forwarders { 127.0.0.1 port 5353; };
    forward only;
...
};
...

If you want to forward to an external TLS proxy (via stunnel), do the same but use only TCP/54 (see stunnel configuration below):

/etc/named.conf
options {
...
    //forwarders { 8.8.8.8; 8.8.4.4; };
    forwarders { 127.0.0.1 port 54; };
    forward only;
...
};
...
server 127.0.0.1 {
    tcp-only yes;
};
...

Optional: If using ISC bind as the the current DNS provider, and you will be providing both forwarding services for legacy clients and DoH to modern clients, you might want to configure named to listen on an alternate port, for example TCP|UDP/54, rather than the default of 53 so that your stub resolver will listen on the standard port. Comment out any existing 'listen' lines and add the following (omit the v6 line if not needed):

/etc/named.conf
...
    //listen-on { any; };
    listen-on port 54 { any; };
    listen-on-v6 port 54 { any; };
...

Unbound

You can easily setup DoT server by adding to your config file port 853 to listening and specify certificate and key paths:

/etc/unbound/unbound.conf
server:
...
interface: 127.0.0.1@853
tls-service-pem: /etc/unbound/public.pem
tls-service-key: /etc/unbound/private.pem
...

DoH server setup is same as DoT, but needed port is 443:

/etc/unbound/unbound.conf
server:
...
interface: 127.0.0.1@443
tls-service-pem: /etc/unbound/public.pem
tls-service-key: /etc/unbound/private.pem
...

Web server configuration

Apache httpd proxy configuration

Configure a proxy in your primary httpd.conf or appropriate vhost listening on 443:

/etc/httpd/conf/vhosts/yourhost.conf
...
    ProxyPass /dns-query http://[127.0.0.1]:8080/dns-query
    ProxyPassReverse /dns-query http://[127.0.0.1]:8080/dns-query
...

Nginx proxy configuration

DoT Proxy

With Nginx stream module you can setup proxy to upstream DNS. Note that you can use local dns as well as third parties.

/etc/nginx/nginx.conf
...
stream {
    upstream dns {
        zone dns 64k;
        server 8.8.8.8:53;
    }
    
    server {
        listen 853 ssl;
        ssl_certificate /etc/nginx/ssl/certs/public.pem;
        ssl_certificate_key /etc/nginx/ssl/private/private.pem;
        proxy_pass dns;
    }
}
...

DoH Proxy

For DoH implementation you need for use additional NJS scripts. You need to get it from this GitHub's page, put it to /etc/nginx/njs.d/ and be sure package nginx-mod-njs is installed.

At first you need to setup stream service, which will be get dns request from nginx's HTTP/2 service, process it with js_filter to find dns packets and pass it to upstream dns server.

/etc/nginx/nginx.conf
...
stream {
    upstream dns {
        zone dns 64k;
        server 1.1.1.1:53;
        
    server {
        listen 127.0.0.1:8053;
        js_filter doh_filter_request;
        proxy_ssl on;
        proxy_pass dns;
        }
}
...

Then, setup HTTP/2 service to listen dns requests at URI /dns-query and relay them to stream service. Note that to a need change certificates to valid

/etc/nginx/nginx.conf
...
upstream dohloop {
   zone dohloop 64k;
   server 127.0.0.1:8053;
}

server {
    listen 443 ssl http2;
    ssl_certificate /etc/nginx/ssl/certs/public.pem;
    ssl_certificate_key /etc/nginx/ssl/private/private.pem;

    location /dns-query {
        proxy_http_version 1.0;
        proxy_pass http://dohloop;
   }
}
...

You can use both DoT and DoH services at same time, caching and multiple upstream dns. For more examples see this config files

DNS over TLS configuration via stunnel

Merge-arrows-2.pngThis article or section is a candidate for merging with stunnel#DNS over TLS.Merge-arrows-2.png

Notes: Some info is provided on the main stunnel page. (Discuss in Talk:DNS over HTTPS servers#)

Configure stunnel to listen on TCP/853 for TLS connections, and forward to your local DNS provider:

/etc/stunnel/conf.d/DoT.conf
[dns]
accept = 853
connect = 127.0.0.1:53
cert = /etc/ssl/private/fullchain.pem
key = /etc/ssl/private/privkey.pem

Configure stunnel to listen on TCP/54 and forward to an upstream secure provider:

/etc/stunnel/conf.d/DoT-Remote.conf
[dnsovertls]
client = yes
accept = 54
connect = 10.10.10.1:853
verifyChain = yes
CAPath = /etc/ssl/certs
checkHost = <your_host_name>

DNS over HTTPS server Docker images

See https://hub.docker.com/r/satishweb/doh-server.