stablestud / adsorber

Ad-blocker for Linux systems purely built on POSIX-compliant shell scripts.

Adsorber

(Ad)sorber blocks ads by 'absorbing' and dumbing them into the void.

Technically speaking, it adds ad-domains to the hostname / DNS lookup file /etc/hosts,
with a redirection to a non-existent ip 0.0.0.0, which prevents ads from being loaded system-wide.

You can consider it as AdAway for non Android systems running on Linux.

Overview

• Features
• Requirements
• Installation
• Removal
• Usage
• Configuration
• Logging
• License

Features

• Blocks advertisements system-wide, not only in the browser
• Prevents annoying anti-adblockers from triggering
• Update your ad-domain list with domains from external external sources (like https://adaway.org/hosts.txt)
• Revert to the previous hosts file if the current hosts file contains broken ad-domains
• Automatically update the hosts file with schedulers (cronjob or systemd service)
• White- and blacklist specific domains

Confirmed working on:

• arch linux
• debian on jessie and buster
• ubuntu on bionic
• gentoo
• solus on fortitude
• fedora on v30+

Adsorber will very likely work on every distribution, as it runs on POSIX shell.

Requirements

• root rights (e.g. with sudo)
• The following should be supported on all distros by default:
  • /bin/sh
  • /etc/hosts
  • curl or wget

Installation

Download Adsorber from releases or clone it.

Two possibilites:

• Install to system (recommended)
• Portable mode without installation

Install (recommended)

Adsorber will be placed onto your system (to /usr/local/).

1. Execute the file ./place_files_onto_system.sh as root
2. Run the command adsorber enable
3. Answer the prompts to configure Adsorber
4. Finished! You can remove the downloaded files.

If you have a super custom system you can configure where Adsorber should be placed, edit the relevant lines in place_files_onto_system.sh and remove_files_from_system.sh
However the default path (/usr/local/) is the default for external scripts on Linux (see here) and should be fine for most systems.

Placing Adsorber has the advantage to run it independently from the user who downloaded it, preventing broken cronjobs/services as there is no risk that the files/directories of Adsorber will be accidentally deleted or moved.

To reverse the steps (complete uninstall) see removal

Portable mode

This mode will only download the recent ad-domains and merges them into your hosts file.
Note: You won't be able to set a scheduler.

1. Execute ./portable_adsorber.sh enable to generate the config files
2. Execute ./portable_adsorber.sh enable again to continue
3. Finished!

If you want to update your hosts file you need to do it yourself by running ./portable_adsorber.sh start If you want to restore your hosts file to its default run ./portable_adsorber.sh stop

Portable-mode won't touch the system except for /etc/hosts which is required to block ad-domains. A backup will be created at /etc/hosts.original.

Removal

Automatic removal

To completely remove Adsorber and all its changes run the script ./remove_files_from_system.sh as root.
The script also works on portable mode setups. However running ./portable_adsorber.sh disable instead should suffice.

Manual removal

If you prefer manual removal, here you go:

1. delete inline:

• /etc/hosts
  Delete everything between the lines: # BEGIN OF ADSORBER SECTION and # END OF ADSORBER SECTION

2. remove:

• /etc/hosts.original
• /usr/local/bin/adsorber
• /usr/local/etc/adsorber/
• /usr/local/lib/adsorber/
• /usr/local/share/adsorber/
• /etc/systemd/system/adsorber.service
• /etc/systemd/system/adsorber.time
• /etc/cron.hourly/80adsorber
• /etc/cron.daily/80adsorber
• /etc/cron.weekly/80adsorber
• /etc/cron.monthly/80adsorber
• /var/cache/adsorber
• /var/log/adsorber.log <- won't be removed automatically
• /etc/hosts.original <- won't be removed automatically
• /tmp/adsorber/

Not all files of the above will exist, so dont worry if they are not found.

Usage

adsorber <operation> [<options>]

Quick link to all operations or options.

Note: if you use portable mode, use ./portable_adsorber.sh instead of adsorber

Default help screen of adsorber help

Usage: adsorber <operation> [<options>|--help]

(Ad)sorber blocks ads by "absorbing" and dumbing them into void.
     (with the help of the hosts file)

Operations (required):
  - enable, setup
      setup necessary things needed for Adsorber
        e.g., create backup file of hosts file,
              create scheduler which updates the host file once a week
  - disable
      completely remove changes made by Adsorber
         e.g., disable scheduler (if set)
               restore hosts file to its original state
  - start, update
      update hosts file with newest ad-domains
  - stop, restore
      restore hosts file to its original state
      (it does not remove the scheduler, this should be used temporary)
  - revert
      reverts the hosts file to the last applied (previous) ad-domains
  - version
      show version of this shell script
  - help
      show this help

Options (optional):
  -y,  --yes, --assume-yes - answer all prompts with 'yes'
  -f,  --force             - force the update if no /etc/hosts backup
                             has been created (dangerous!)
  -h,  --help              - show specific help of specified operations
                             (e.g 'adsorber update --help)
  --noformatting           - turn off coloured and formatted output

Scheduler options (use with 'enable'):
  -ns, --no-scheduler      - skip scheduler creation
  -s,  --systemd           - setup Systemd as scheduler
  -c,  --cron              - setup Cronjob ...
  -H,  --hourly            - run scheduler once hourly
  -D,  --daily                              ... daily
  -W,  --weekly                             ... weekly
  -M,  --monthly                            ... monthly
  -Q,  --quarterly                          ... quarterly (4x a year)
  -S,  --semiannually                       ... semiannually (2x a year)
  -Y,  --yearly                             ... yearly

Config files are located at: /usr/local/etc/adsorber/

Documentation: https://github.com/stablestud/adsorber/blob/master/README.md
If you encounter any issues please report them to the Github repository.

Operations (required):

To run Adsorber one of the following operations must be given:

• enable
• disable
• start
• stop
• revert

Note: to get further information about a operation run it with --help,
e.g.: adsorber start --help

adsorber enable/setup {options}:

You should run this command first. It is required to make Adsorber functional.

The command will:

• backup your /etc/hosts file to /etc/hosts.original (if not other specified in adsorber.conf)
• setup a scheduler which updates your hosts file with ad-server domains once a week. (either systemd, cronjob or none)
• fetch the newest ad-server domains in your hosts file. (same as update)

Possible options are:

• -s, --systemd
• -c, --cronjon
• -ns, --no-scheduler
• -y, --yes, --assume-yes
• -h, --help
• -H, --hourly
• -D, --daily
• -W, --weekly
• -M, --monthly
• -Q, --quarterly
• -S, --semiannually
• -Y, --yearly

adsorber disable {options}:

Completely disable all background tasks (schedulers) and remove all changes made by Adsorber.
However it will not remove Adsorber from the system. The adsorber command will be still available.
To completely uninstall see removal.

The command will:

• disable all schedulers (systemd, cronjob)
• restore the hosts file to it's original state
• remove all leftovers (cache, etc)

Possible options are:

• -y, --yes, --assume-yes
• -h, --help

Options (optional):

• -s, --systemd
• -c, --cronjon
• -ns, --no-scheduler
• -y, --yes, --assume-yes
• -f, --force
• -h, --help
• --noformatting

adsorber stop/revert {options}:

Reverts the last applied hosts-file by Adsorber.

The command will:

• downgrade /etc/hosts with ad-domains applied previously

This is useful if the newest hosts file contains less or no ad-domains, because a source
was unreachable and you don't want to loose the ad-servers supplied previously from this source.

Possible option:

• -h, --help

adsorber start/restore {options}:

Updates the hosts file with the latest ad-domains.

The command will:

• copy the current /etc/hosts to /etc/hosts.previous, if not disabled in adsorber.conf
• download ad-server domains from servers listed in sources.list
• filter those and apply them to the systems hosts file /etc/hosts

Possible options are:

• -f, --force
• -h, --help

adsorber stop/restore {options}:

Restores the hosts file to its original state, without removing its backup and scheduler.

The command will:

• Remove Adsorber's inserted lines from /etc/hosts.

Note: If Adsorber's scheduler was set-up, it'll re-apply ad-server domains to your hosts file when triggered.
For this reason this command is used to temporary disable Adsorber,
e.g. when it's blocking some sites you need to access for a short period of time.

To re-apply run adsorber revert (for previous host file) or adsorber update (for updated version).

Possible option:

• -h, --help

-s, --systemd:

Option is only available with operation setup.
Adsorber uses Systemd as a scheduler to update your hosts file periodically.

• Setup systemd scheduler, skipping the scheduler prompt.

Files are placed into /etc/systemd/system by default.

-c, --cronjob:

Option is only available with operation setup.
Adsorber uses Cronjob as a default scheduler to update your hosts file periodically.

• Setup the cron scheduler, skipping the scheduler prompt.

File is placed into /etc/cron.weekly/ by default.

-ns, --no-scheduler:

Option is only available with operation setup.
Tells Adsorber to not install a scheduler.

• Skips the setup of a scheduler, therefore skipping the scheduler prompt.

Adsorber won't update the host file periodically, therefore
you'll have to update it manually with adsorber update.

-y, --yes, --assume-yes:

Answers all prompts with yes e.g.,

• Do you really want to setup Adsorber?
• Do you really want to disable Adsorber?

Note: it'll not answer prompts which may harm your system. But --force will.

-f, --force:

Option is only available with operation update.

This will force the script to continue (dangerous!) the update e.g.,

• Continues if no backup has been created, overwriting the existing hosts file.

-h, --help:

Show general help or if specified with an operation,
show specific help about operation e.g.,
adsorber setup --help

--noformatting:

Disables coloured and formatted output by Adsorber.
Can be used with every operation or option.
Useful for logging to files and output processing by other scripts.

Configuration:

By default the config files are located at /usr/local/etc/adsorber/.
In portable-mode the config files are being created at the scripts root directory after the first run.

Config files you may want to edit:

• adsorber.conf - general configuration
• sources.list - sources to fetch from
• whitelist - domains which should not be blocked
• blacklist - domains which should be always blocked

By default Adsorber uses the following external sources:

• adaway.org (also used by AdAway)
• yoyo.org (also used by AdAway)

To add your own ad-domain sources, just add them to sources.list.

Logging:

Schedulers (systemd service or cronjob) will pass their output to the Syslog process and to /var/log/adsorber.log.
The syslog can be examined at /var/log/syslog.

Todo for future releases

You're free to implement things listed -or- not listed in TODO.md to Adsorber. Any additions are always appreciated. :)

License

MIT License

Copyright (c) 2017 stablestud

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the Software), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.