DNS over HTTPS in VyOS

Categories: dns cloudflare firewall

VyOS is using PowerDNS recurser for DNS forwarding. Unfortunately it’s not possible to make encrypted DNS queries from it, so here’s a work around with cloudflared tunnel as a DNS Proxy

1. Log in to vyos as root and create a directory in /etc for cloudflared

ssh [email protected] # Change the ip to your routers ip
vyos@vyos:~$ conf
vyos@vyos# sudo -s
root@vyos# mkdir /etc/cloudflared

2. Install cloudflared

root@vyos# wget https://github.com/cloudflare/cloudflared/releases/latest/download/cloudflared-linux-amd64.deb
root@vyos# dpkg -i cloudflared-linux-amd64.deb

3. Configure cloudflared

root@vyos# cloudflared tunnel login
root@vyos# cloudflared tunnel create vyos
# This will create a tunnel-id.json file with your cloudflare credentials.

echo "
tunnel: <YOUR-TUNNEL-ID>
credentials-file: /etc/cloudflared/<YOUR-TUNNEL-ID>.json

proxy-dns: true
proxy-dns-port: 53
 - https://cloudflare-dns.com/dns-query
 - https://security.cloudflare-dns.com/dns-query # Blocks Malware
 - https://family.cloudflare-dns.com/dns-query # Blocks Malware and Adult Content
 - https://dns.quad9.net/dns-query
 - https://dns.google/dns-query
 - https://doh.opendns.com/dns-query
 - https://doh.familyshield.opendns.com/dns-query # This is their familyshield with adult content filtering
" > /etc/cloudflared/config.yml

root@vyos# cloudflared service Install
root@vyos# systemctl enable --now cloudflared.service

You can choose the proxy-dns-upstream server of your liking. I have listed a few of the public resolvers with support for DoH (RFC 8484)

4. Configure VyOS to use the dns-proxy

vyos@vyos# set system name-server
vyos@vyos# delete system name-server x.x.x.x # This is optional and is needed if your system is already configured to use a dns resolver
vyos@vyos# commit
vyos@vyos# save

5. Verify it’s working

vyos@vyos# dig google.com

; <<>> DiG 9.16.27-Debian <<>> google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 444
;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 1

; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 91031139f2dce048 (echoed)
;google.com.			IN	A

google.com.		217	IN	A
google.com.		217	IN	A
google.com.		217	IN	A
google.com.		217	IN	A
google.com.		217	IN	A
google.com.		217	IN	A

;; Query time: 43 msec
;; WHEN: Mon Oct 03 10:45:01 CEST 2022
;; MSG SIZE  rcvd: 207

As shown above, VyOS is now using port 53 on localhost for dns resolution