pftbld(8)

pftbld(8) is a lightweight OpenBSD daemon written to automate pf(4) table content management and is typically used for building and maintaining dynamic firewall blocklists.

For further information, please have a look at the manpages of pftbld(8), its configuration file pftbld.conf(5), and its control tool pftblctl(8).

How to interface

Other programs usually interact with pftbld by sending plain text messages to specified UNIX-domain sockets.

The most common cases probably are:

• httpd(8)
  • via FastCGI as outlined in pftbld.conf(5)
  • natively through the httpd-plus add-on package
• sshd(8)
  • by means of saltan(8) which is tracking the authentication log file

How to install

pftbld needs to be built from sources and installed manually. Luckily, this is easy and straightforward. Just follow the steps below.

First of all, make sure you're running OpenBSD-current. Otherwise, one of the following branches might be more appropriate:

• 7.5-stable
• 7.4-stable

Then, make sure your user (e.g. mpfr) has sufficient doas permissions.

$ cat /etc/doas.conf
permit nopass mpfr

Download and extract the source files into the user's home directory, here /home/mpfr.

$ cd
$ pwd
/home/mpfr
$ doas rm -rf pftbld-current/
$ ftp -Vo - https://codeload.github.com/mpfr/pftbld/tar.gz/current | tar xzvf -
pftbld-current
pftbld-current/LICENSE
pftbld-current/README.md
pftbld-current/docs
pftbld-current/docs/pftblctl.8.html
pftbld-current/docs/pftbld.8.html
pftbld-current/docs/pftbld.conf.5.html
pftbld-current/pkg
pftbld-current/pkg/pftbld.conf
pftbld-current/pkg/pftbld.rc
pftbld-current/src
pftbld-current/src/Makefile
pftbld-current/src/config.c
pftbld-current/src/listener.c
pftbld-current/src/log.c
pftbld-current/src/log.h
pftbld-current/src/logger.c
pftbld-current/src/parse.y
pftbld-current/src/persist.c
pftbld-current/src/pftblctl.8
pftbld-current/src/pftblctl.sh
pftbld-current/src/pftbld.8
pftbld-current/src/pftbld.c
pftbld-current/src/pftbld.conf.5
pftbld-current/src/pftbld.h
pftbld-current/src/scheduler.c
pftbld-current/src/sockpipe.c
pftbld-current/src/tinypfctl.c
pftbld-current/src/util.c

Compile the source files.

$ cd pftbld-current/src
$ doas make
yacc  -o parse.c parse.y
cc -O2 -pipe  -Wall -I/home/mpfr/pftbld-current/src -Wstrict-prototypes ...
.
.
.
cc   -o pftbld parse.o config.o listener.o log.o logger.o persist.o ...

Install daemon, manpages, service script, the daemon's user/group and a sample configuration file.

$ doas make fullinstall
install -c -s  -o root -g bin  -m 555 pftbld /usr/local/sbin/pftbld
install -c -o root -g bin -m 555  /home/mpfr/pftbld-current/src/pftblctl.sh ...
install -c -o root -g bin -m 444  pftblctl.8 /usr/local/man/man8/pftblctl.8
install -c -o root -g bin -m 444  pftbld.8 /usr/local/man/man8/pftbld.8
install -c -o root -g bin -m 444  pftbld.conf.5 /usr/local/man/man5/pftbld.conf.5
install -c -o root -g bin -m 555  /home/mpfr/pftbld-current/src/../pkg/pftbld...
useradd -c "pftbld unprivileged user" -d /var/empty -g =uid -r 100..999 -s ...
cp /home/mpfr/pftbld-current/src/../pkg/pftbld.conf /etc/pftbld

For further usage, the following list of available installation targets might be helpful:

target name	description
fullinstall	installs daemon, manpages, service script, user/group and a sample configuration file if a configuration file not yet exists
fulluninstall	deletes everything installed by fullinstall but leaves the configuation file untouched if it was changed
install	installs daemon and manpages only
reinstall	runs fulluninstall, then fullinstall
uninstall	deletes daemon and manpages
update	compiles the sources and runs fullinstall

Activate the service script.

$ doas rcctl enable pftbld

Adapt the sample configuration file at /etc/pftbld/pftbld.conf to your needs. Make sure your configuration is valid.

$ doas vi /etc/pftbld/pftbld.conf
...
$ doas pftbld -n
configuration OK

Start the pftbld daemon.

$ doas rcctl start pftbld
pftbld(ok)

How to uninstall

Stop the pftbld daemon.

$ doas rcctl stop pftbld
pftbld(ok)

Deactivate the service script.

$ doas rcctl disable pftbld

Uninstall daemon, manpages, service script and the daemon's user/group.

$ cd ~/pftbld-current/src
$ doas make fulluninstall
rm /usr/local/sbin/pftbl* /usr/local/man/man{5,8}/pftbl*
rm /etc/rc.d/pftbld
userdel _pftbld
groupdel _pftbld
(configuration directory has changed, not touching /etc/pftbld)

Configuration and source directory need to be removed manually, if no longer needed.

$ doas rm -rf /etc/pftbld ~/pftbld-current