prerm is in freeradius 2.2.5+dfsg-0.2+deb8u1.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51  | #! /bin/sh
set -e
case "$1" in
  remove)
        if [ -x "`which invoke-rc.d 2>/dev/null`" ]; then
		invoke-rc.d freeradius stop
	else
		/etc/init.d/freeradius stop
	fi
        for file in /etc/freeradius/preproxy_users \
          /etc/freeradius/policy.conf \
          /etc/freeradius/eap.conf \
          /etc/freeradius/experimental.conf \
          /etc/freeradius/huntgroups \
          /etc/freeradius/proxy.conf \
          /etc/freeradius/attrs.pre-proxy \
          /etc/freeradius/hints \
          /etc/freeradius/sql.conf \
          /etc/freeradius/ldap.attrmap \
          /etc/freeradius/attrs \
          /etc/freeradius/policy.txt \
          /etc/freeradius/attrs.accounting_response \
          /etc/freeradius/attrs.access_reject \
          /etc/freeradius/attrs.access_challenge \
          /etc/freeradius/clients.conf \
          /etc/freeradius/acct_users
        do
          if dpkg-statoverride --list $file >/dev/null; then
            dpkg-statoverride --remove $file
          fi
        done
        for dir in /etc/freeradius/certs \
          /etc/freeradius/sites-available \
          /etc/freeradius/sites-enabled \
          /var/run/freeradius \
          /var/log/freeradius
        do
          if dpkg-statoverride --list $dir >/dev/null; then
            dpkg-statoverride --remove $dir
          fi
        done
	;;
esac
exit 0
 |