From 58f42a7913625afda9550ce99328af9e8ede2df7 Mon Sep 17 00:00:00 2001 From: Jon Lockwood Date: Fri, 18 Feb 2022 11:58:59 +0930 Subject: [PATCH] feat(postfix): Enforce SMTPD sender restrictions Default is to accept all mail from sender after filtering. smtpd_sender_restrictions rules and order are as follows: 1. permit_mynetworks permit my network (localhost). Placed first as sometimes the sender will not be a FQDN sender. (i.e. cron) 2. reject_non_fqdn_sender bounce mail where sender not in format of FQDN. 3. reject Reject all remaining senders MR !7 --- dockerfile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/dockerfile b/dockerfile index c3adde7..0666c58 100644 --- a/dockerfile +++ b/dockerfile @@ -197,6 +197,8 @@ RUN postconf -e "maillog_file=/var/log/postfix.log" \ && postconf -e "smtpd_client_restrictions=reject_unauth_destination,reject_unauth_pipelining,permit_mynetworks,permit_auth_destination,reject" \ # HELO/EHLO restrictions && postconf -e "smtpd_helo_restrictions=permit_mynetworks,reject_invalid_helo_hostname,permit" \ + # MAIL FROM restrictions + && postconf -e "smtpd_sender_restrictions=permit_mynetworks,reject_non_fqdn_sender,permit" \ EXPOSE 25 587 993 4190