A sendmail milter to reject any commands from a host that HELO's as ylmf-pc, which is commonly seen as performing a dictionary attack on the SMTP server.
This was originally part of me playing around with the milter interface.
Author: David L. Cathey c/o Montagar Software, Inc. P.O.Box 260772 Plano, TX 750226-0772
Copyright (c) 2014, Montagar Software, Inc.
See COPYING for license information.
sendmail
./configure --prefix=/usr
Add a similar line to /etc/mail/sendmail.mc:
INPUT_MAIL_FILTER(`milter-ylmf', `S=unix:/var/run/milter-ylmf.sock, T=S:30s;R:30s;E:5m')
Add the following file to /etc/init:
milter-ylmf.conf
Rebuild sendmail.cf, and restart:
make
systemctl restart sendmail
This file will insure the milter is started before sendmail is started