dns crap

scripts and info related to dnscrypt and alternative dns systems

root script: dnscrapt 🡇

A script designed to make managing dnscrypt (and regular dns) easier for me on my CentOS servers.

Requirements:
A properly installed dnscrypt-proxy (see the next section on installing that)

Install:

chmod +x dnscrapt
mv dnscrapt /usr/sbin/

Usage:
dnscrapt update -- updates dnscrypt-resolvers.csv
dnscrapt list -- lists the best dnscrypt resolvers. DNSSEC+NO_LOGS+NAMECOIN come first and then DNSSEC+NO_LOGS
dnscrapt <dnscrypt-resolver> [<backup-dnscrypt-resolver>] -- runs the dnscrypt-proxy service with the chosen resolver(s). max: 2
dnscrapt <opennic-au|opennic-ch|opennic-de|opennic-ec|opennic-fr|opennic-it|opennic-jp|opennic-ro|opennic-si|opennic-uk|opennic-us -- switches to regular dns and uses opennic resolvers belonging to the specified region
dnscrapt <okturtles|level3|opendns> -- switches to one of the regular dns providers listed

Notes:
I like to use dnscrapt soltysiak-ipv6 soltysiak, which makes soltysiak-ipv6 the primary resolver and soltysiak as a backup (for when ipv6 is acting up). The non-dnscrypt options are available only as backups for when no dnscrypt resolvers are working (for whatever reason). okturtles would be the preferred non-dnscrypt backup option, with the opennic servers following. level3 and opendns probably cant be trusted much but they work when nothing else does.
I manually added the opennic servers from opennicproject and they can change any time. I also added in IPv6 servers and gave them priority, so it might cause problems on servers without IPv6. I got the okTurtles dnschain server from dnschain github. To have it run on boot just add your dnscrapt command to your start up scripts. I add the command to the file /etc/rc.local

TODO:

1. Add a way to scrape the opennic servers page and deliver best results
2. Add an option to list ALL dnscrypt resolvers or search through them
3. Put non-dnscrypt resolvers in a config file of some sort instead of hardcoding them, which also lets users add their own custom servers

installing dnscrypt on linux (centOS)

I don't think the instructions will be very different on other UNIX sytems. The instructions below download+install the latest version of the dependency libsodium and then download+install the latest version of dnscrypt-proxy. Then it downloads the latest dnscrypt-resolvers.csv and adds the system user dnscrypt for running the service.

wget https://download.libsodium.org/libsodium/releases/LATEST.tar.gz -O libsodium.tar.gz
tar -xzvf libsodium*.tar.gz
cd libsodium*
./configure
make && make install
echo /usr/local/lib > /etc/ld.so.conf.d/usr_local_lib.conf
ldconfig
cd ..
rm -rf libsodium*

wget https://download.dnscrypt.org/dnscrypt-proxy/LATEST.tar.gz -O dnscrypt-proxy.tar.gz
tar -xzvf dnscrypt*.tar.gz
cd dnscrypt*
./configure
make && make install
cd ..
rm -rf dnscrypt*

wget https://raw.githubusercontent.com/jedisct1/dnscrypt-proxy/master/dnscrypt-resolvers.csv -O /usr/local/share/dnscrypt-proxy/dnscrypt-resolvers.csv

groupadd dnscrypt
useradd -r -g dnscrypt -s /sbin/nologin dnscrypt -d /var/lib/dnscrypt
mkdir /var/lib/dnscrypt
chown -R dnscrypt.dnscrypt /var/lib/dnscrypt
chmod -R 600 /var/lib/dnscrypt

That's it! Now use my dnscrapt script which is above or run the proxy manually and then edit your system dns settings. CentOS example:

dnscrypt-proxy -E -R cloudns-syd -d -u dnscrypt
echo "nameserver 127.0.0.1" > /etc/resolv.conf

or you could run another one as a backup resolver, on another port, and specify the ports in your resolv.conf like this:

dnscrypt-proxy -a 127.0.0.1:53 -E -R cloudns-syd -d -u dnscrypt
dnscrypt-proxy -a 127.0.0.1:54 -E -R cloudns-can -d -u dnscrypt
echo "nameserver 127.0.0.1#53" > /etc/resolv.conf
echo "nameserver 127.0.0.1#54" >> /etc/resolv.conf

To have it run on boot just add the commands you use to run it in your start up scripts. I add the commands to the file /etc/rc.local

dnscrypt resolvers list

I'm working on a page https://berr.yt/h/dnscrypt-resolvers/ which aims to make it easier to view dnscrypt-resolvers.csv since there is currently no good way to do so. It's a WIP.

TODO:

1. sorting of columns

sources and further reading

• http://dnscrypt.org/
• https://github.com/jedisct1/dnscrypt-proxy
• https://github.com/okTurtles/dnschain
• https://namecoin.info/
• http://emercoin.com/EMCDNS_and_NVS
• https://www.opennicproject.org/

TODO

1. Add my windows version of dnscrapt
2. Talk about alt dns like opennic and namecoin/dnschain