From a1324157b3186dba4eafb376901706b009735575 Mon Sep 17 00:00:00 2001 From: Randy Bush Date: Sat, 4 Jul 2020 14:08:30 -0700 Subject: [PATCH] from wiki --- pages/UbuntuSMTP.md | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/pages/UbuntuSMTP.md b/pages/UbuntuSMTP.md index e69de29..557644e 100644 --- a/pages/UbuntuSMTP.md +++ b/pages/UbuntuSMTP.md @@ -0,0 +1,40 @@ +# Blocking Unwanted SMTP + +``` +iptables -A INPUT -i eth0 -p tcp --destination-port 25 -s 127.0.0.1 -j ACCEPT +iptables -A INPUT -i eth0 -p tcp --destination-port 25 -s 147.28.0.62 -j ACCEPT +iptables -A INPUT -i eth0 -s 198.180.150.1 -j ACCEPT +ip6tables -A INPUT -i eth0 -p tcp --destination-port 25 -s ::1 -j ACCEPT +ip6tables -A INPUT -i eth0 -p tcp --destination-port 25 -s 2001:418:1::62 -j ACCEPT +ip6tables -A INPUT -i eth0 -s 2001:418:8006::1 -j ACCEPT +iptables -A INPUT -i eth0 -p tcp --destination-port 25 -j DROP +ip6tables -A INPUT -i eth0 -p tcp --destination-port 25 -j DROP +iptables-save -c > /etc/iptables.rules +ip6tables-save -c > /etc/ip6tables.rules +cat > /etc/network/if-pre-up.d/iptables << EOF +#!/bin/sh + +iptables-restore < /etc/iptables.rules +ip6tables-restore < /etc/ip6tables.rules + +exit 0 +EOF +cat > /etc/network/if-post-down.d/iptables << EOF +#!/bin/sh + +iptables-save -c > /etc/iptables.rules +ip6tables-save -c > /etc/ip6tables.rules + +if [ -f /etc/iptables.rules ]; then + iptables-restore < /etc/iptables.rules + fi + +if [ -f /etc/ip6tables.rules ]; then + ip6tables-restore < /etc/ip6tables.rules + fi + +exit 0 +EOF +chmod 755 /etc/network/if-pre-up.d/iptables /etc/network/if-post-down.d/iptables +``` +