How to easily create your own adblock using Dnsmasq
Hi folks, today we will learn how to build your own adblock, one that does not sell your navigation data to big corporations.
We will be using Dnsmasq as our DNS server which will have a list of domains to block (spoiler: domain ads). And we will update that list everyday by cron. Of course that means that you should then update your DNS to use the one we are configuring.
apt update && apt install dnsmasq
yum update && yum install dnsmasq
We copy the original file in case we want to restore it
cp /etc/dnsmasq.conf /etc/dnsmasq.conf.ori
Then create a configuration file named /etc/dnsmasq.conf and put the following content
domain-needed bogus-priv resolv-file=/etc/dnsmasq-dns.conf strict-order user=dnsmasq group=dnsmasq addn-hosts=/etc/dnsmasq-hosts.conf expand-hosts domain=mydomain.lan
Replace mydomain.lan by a custom domain you would like to be served via your DNS.
Omit the line if you don't want to serve one.
Open your firewall on port 53 both in UDP and TCP.
Create a file named /etc/dnsmasq-dns.conf and put the following inside:
nameserver 22.214.171.124 nameserver 126.96.36.199
If you don't like Cloudflare's DNS, feel free to use others.
If you've put the line "domain" in /etc/dnsmasq.conf, then create a file named /etc/dnsmasq-custom.conf where you will put custom domain resolution like :
127.0.0.1 alpha 127.0.0.1 beta
They will resolve as alpha.mydomain.lan and beta.mydomain.lan
Create a file called /etc/cron.daily/adblocker and put the following content
#!/bin/bash curl -s -o /etc/dnsmasq-adblock https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts cat /etc/dnsmasq-custom > /etc/dnsmasq-hosts.conf cat /etc/dnsmasq-adblock >> /etc/dnsmasq-hosts.conf systemctl restart dnsmasq
Basically what we are doing is :
- getting the last version of the ads domains
- put any custom domain to dnsmasq hosts file
- append ads domain to the previous list
- restart dnsmasq
We are using the excellent project https://github.com/StevenBlack/hosts
Feel free to use another list or even run your own. It will work as long as it's a list in the same format than an hosts file.
Setting up and maintaining your own adblock is really easy.
Also if you wish to use it as you go like on your mobile phone, feel free to use my tutorial about Wireguard.
That's all folks!