hostblock

Block domains using hosts file entries.

Installation

install from pypi (recommend)

pip3 install hostblock

install from github (latest master)

pip3 install -U git+https://github.com/nul-one/hostblock.git

Usage

Run hostblock apply to add list of undesired hosts to your /etc/hosts file resolving to 0.0.0.0. It will ask for sudo password.

Local blacklist and whitelist

Hostblock will automatically create a json file ~/.hostblock where it keeps your local blacklist and whitelist. When using hostblock apply your local whitelist will be subtracted from your blacklist and the result will be then put into your /etc/hosts.

Here is how you can control your local list:

• hostblock ab HOST1 HOST2 ... this will add single or multiple hosts to your blacklist
• hostblock rb HOST1 HOST2 ... remove single or multiple hosts from your blacklist
• hostblock cb remove (clear) all hosts from your blacklist
• hostblock lb list all hosts currently in your blacklist
• hostblock aw HOST1 HOST2 ... this will add single or multiple hosts to your whitelist
• hostblock rw HOST1 HOST2 ... remove single or multiple hosts from your whitelist
• hostblock cw remove (clear) all hosts from your whitelist
• hostblock lw list all hosts currently in your whitelist
• hostblock list list hosts from blacklist that do not appear in whitelist
• hostblock count show counts for blacklist and whitelist

Commands that don't change config files such as lw, lb, list and count can be followed by a list of configuration files. In that case default config file or --config option will be ignored and unified data will be displayed. Config files will not be touched in either case:

hostblock count first.config second.config third.config

The apply option can be followed by list of configs in similar manner. If so, unified config data will be applied to /etc/hosts or other selected hostname:

hostblock apply .hostblock first.config second.config third.config

In example above, we listed the default .hostblock config file. If we didn't, it wouldn't be used.

Importing

To import a list of hosts, just pass it as argument to ab or aw command.
Here is an example bash script that will import lists from http://someonewhocares.org and https://github.com/notracking/hosts-blocklists lists into blacklist of multiple config files and then apply those including your default one to your hosts file:

#!/bin/bash

set -e

echo "Updating 'notracking/hosts'..."
curl -s https://raw.githubusercontent.com/notracking/hosts-blocklists/master/domains.txt \
    | fdump -p '^address=/(.*)/.*$' '{0}' \
    | xargs hostblock -c ~/.hostblock.notracking ab

echo "Updating 'notracking/domains'..."
curl -s https://raw.githubusercontent.com/notracking/hosts-blocklists/master/domains.txt \
    | fdump -p '^address=/(.*)/.*$' '{0}' \
    | xargs hostblock -c ~/.hostblock.notracking ab

echo "Updating 'someonewhocares/hosts'..."
curl -s http://someonewhocares.org/hosts/zero/hosts \
    | fdump -d "130.211.230.53" -p '^0\.0\.0\.0 ([a-zA-Z0-9\._-]+)\s.*' '{0}' \
    | xargs hostblock -c .hostblock.someonewhocares ab

hostblock count ~/.hostblock*

echo "Applying to /etc/hosts..."
hostblock apply ~/.hostblock*

The above example uses fdump tool for easy filtering. You may install the tool with pip3 install fdump or use grep/awk alternatives in it's place.
I use the above script as a daily cron-job. I only add new things manually into my default config file to keep it separate.

Merging

To merge your friend's whitelist and blacklist, see the following example:

hostblock --config friends.hostblock lb | xargs hostblock ab
hostblock --config friends.hostblock lw | xargs hostblock aw

Notes

• Do not use sudo when running hostblock commands. Hostblock will ask for sudo password when required to modify hosts file. If you use sudo then hostblock will think you are root user and will look for settings file in /root/.hostblock thinking that's your home dir. If you really need to use sudo, make sure to specify proper hostblock config with --config option.
• When adding duplicate domains to your blacklist or whitelist, hostblock will keep only single entry, so no worries!