From Qmail Info Wiki
#!/bin/bash
# ftpauth: This program is called by pure-authd to check if the email l/p are correct
# Copyright (C) 2005 Roman Volf
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
VPOPHOME=/home/vpopmail
## Do not change anything below here
PATH=$PATH:$VPOPHOME/bin
VPOPMAIL_UID=`printf "%s\0%s\0%s\0" $AUTHD_ACCOUNT $AUTHD_PASSWORD Y123457 | vchkpw id -u vpopmail 3<&0`
VPOPMAIL_GID=`id -g vpopmail`
DOMAIN_DIR=`vdominfo -d $DOMAIN`
USER_DIR=`vuserinfo -d $AUTHD_ACCOUNT`
if [ $VPOPMAIL_UID ]; then
DOMAIN=`echo $AUTHD_ACCOUNT|cut -d "@" -f 2`
USER=`echo $AUTHD_ACCOUNT|cut -d "@" -f 1`
DOMAIN_DIR=`vdominfo -d $DOMAIN`
if [ ! -f $DOMAIN_DIR/.qmail-$USER ]; then
echo "| /var/qmail/bin/preline /usr/local/bin/preprocmail" > $DOMAIN_DIR/.qmail-$USER
echo "| $VPOPHOME/bin/vdelivermail '' $USER_DIR/Maildir/" >> $DOMAIN_DIR/.qmail-$USER
chown vpopmail $DOMAIN_DIR/.qmail-$USER
chmod 600 $DOMAIN_DIR/.qmail-$USER
fi
echo "auth_ok:1"
echo "uid:$VPOPMAIL_UID"
echo "gid:$VPOPMAIL_GID"
echo "dir:$USER_DIR"
echo "end"
exit
fi
echo "auth_ok:0"
echo "end"