A simple anti-spam system for
[question2answer](https://www.question2answer.org/qa/), using [the
stopforumspam API](https://www.stopforumspam.com/usage) and system firewall
([pf](https://www.openbsd.org/faq/pf/filter.html) or
[ufw](https://launchpad.net/ufw)).

To deploy:

1. Modify the configuration variables in the scripts as needed.

2. Copy the scripts to `/usr/local/bin` (requires root):

        install -m 755 -o root -g bin forumspam.sh /usr/local/bin/forumspam.sh
        install -m 755 -o root -g bin q2a_usercheck.sh /usr/local/bin/q2a_usercheck.sh
        install -m 640 -o _forumspam /dev/null /var/log/forumspam.log

3. Create the user the scripts will run as:

        useradd -s $(which nologin) _forumspam

4. Set up the firewall program

If using `ufw`, install it:

        apt update
        apt install ufw

If using `pf`:

Create appropriate permissions for the file:

        install -m 640 -o _forumspam -g wheel /dev/null /etc/pf-forumspam.txt

Add the following to `/etc/pf.conf`, preferably high up in the ruleset:

        table <forumspam> persist file "/etc/pf-forumspam.txt"
        block in quick on egress from <forumspam>
        block out quick on egress to <forumspam>

5. Give the `_forumspam` user restrictive sudo or doas permissions:

If using doas, add the following to `/etc/doas.conf`:

        permit nopass _forumspam cmd pfctl args -nf /etc/pf.conf
        permit nopass _forumspam cmd pfctl args -t forumspam -T replace -f /etc/pf-forumspam.txt

If using sudo, add to your sudo config file:

          _forumspam ALL = NOPASSWD: /usr/sbin/ufw

Note: the path to `ufw` may be different depending on your linux distribution.

6. Register the systemd unit or rc script.

systemd:

    sudo cp forumspam.service /etc/systemd/system/
    sudo systemctl enable forumspam
    sudo systemctl start forumspam

TODO:

* also check against [botscout](http://botscout.com/api.htm)
* give the scripts more sensible names
* also create an rc script
* support `iptables`
* create a Makefile
* merge the two scripts into one