Encrypt DNS Traffic in Ubuntu Linux with DNSCrypt - DNSCrypt is a protocol that authenticates communications between a DNS client and a DNS resolver. This is great tool for securing communications, prevents DNS spoofing, man-in-the-middle attacks (MITM), and spoofing.
DNSCrypt uses cryptographic signatures to verify that responses originate from the chosen DNS resolver and haven't been tampered with.
DNSCrypt uses cryptographic signatures to verify that responses originate from the chosen DNS resolver and haven't been tampered with.
DNSCrypt available for major operating systems, including Linux, OSX, Android, iOS, BSD and Windows. Start from Ubuntu 16.04 LTS, DNSCrypt can now be installed without adding the PPA into the system.
Installing Dnscrypt-Proxy in Ubuntu Linux
To install dnscrypt-proxy package on Ubuntu 16.04 LTS Xenial Xerus and based Linux distribution is as easy. We can easily install the package without adding a PPA into the system.
Step 1 - First, please ensure you have the universe repository is enabled. You can enable the repository by adding this line :
deb http://us.archive.ubuntu.com/ubuntu xenial main universe
into Ubuntu sources.list that located in /etc/apt/ directory. Well, if you love the GUI based, you can easily enable it in Software & Updates.
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Step 2 - After any changes you should run this command in terminal window to update your system :
sudo apt-get update
Step 3 - You can now install the package just like this :
sudo apt-get install dnscrypt-proxySetting Up Network Connection DNS Server
After installing DNSCrypt, you need to set the network connection DNS server to 127.0.0.2. We can use Network Manager GUI to change the DHCP settings.
Step 1 - Head to Ubuntu panel, then click at Network Manager indicator
Step 2 - Open Edit Connections, then select your connection and click Edit
Step 3 - Switch to the IPv4 Settings tab
If you're using Manual / static IP, enter 127.0.0.2 under DNS servers, then save the configuration. See the screenshot :
If you're using Automatic (DHCP), change it to Automatic (DHCP) addresses only, then simply add 127.0.0.2 under DNS servers as shown :
Step 4 - Final touch, now restart the network connection. Head to Network indicator then Enable Networking twice. It's mean disable and then re-enable.
Checking The DNS
Time to check the new configuration. Visit https://www.opendns.com/welcome/. If you have changed the DNS correctly to OpenDNS, the page will tell you as shown :
Another way to checking if dnscrypt-proxy is working is run this command from your Ubuntu's terminal :
sudo tcpdump -i eth0
Change eth0 with your with your current network interface like wlan0, wlan1, etc. You can find the network interface using ifconfig.
If you see resolver2.opendns.com.https then it means the OpenDNS via DNSCrypt works correctly.
Well, that's all I can write about step-by-step to do to install and configure DNSCrypt / dnscrypt-proxy in Ubuntu 16.04 LTS. Visit http://dnscrypt.org/ for more information.