From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Steffen Bisgaard" <sbisgaard@xtrasource.com>
Subject: SMTP
Date: Tue, 21 Jan 2003 16:24:36 +0100
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To: netfilter@lists.netfilter.org

Hallo all,

Can anybody tell me why the following doesn't allow me to send and receive
email?

# POP server (110)
# ----------------
iptables -A INPUT -i $EXTERNAL_INTERFACE -p tcp \
--source-port $UNPRIVPORTS \
-d $IPADDR --destination-port 110 -j ACCEPT
iptables -A OUTPUT -o $EXTERNAL_INTERFACE -p tcp ! --syn \
-s $IPADDR --source-port 110 \
--destination-port $UNPRIVPORTS -j ACCEPT
# POP client (110)
# ----------------
iptables -A INPUT -i $EXTERNAL_INTERFACE -p tcp ! --syn \
--source-port 110 \
-d $IPADDR --destination-port $UNPRIVPORTS -j ACCEPT
iptables -A OUTPUT -o $EXTERNAL_INTERFACE -p tcp \
-s $IPADDR --source-port $UNPRIVPORTS \
--destination-port 110 -j ACCEPT


# ------------------------------------------------------------------
# SMTP server (25)
# ----------------
iptables -A INPUT -i $EXTERNAL_INTERFACE -p tcp \
--source-port $UNPRIVPORTS \
-d $IPADDR --destination-port 25 -j ACCEPT
iptables -A OUTPUT -o $EXTERNAL_INTERFACE -p tcp ! --syn \
-s $IPADDR --source-port 25 \
--destination-port $UNPRIVPORTS -j ACCEPT
#
#
#
# ------------------------------------------------------------------
# SMTP client (25)
# ----------------
iptables -A INPUT -i $EXTERNAL_INTERFACE -p tcp ! --syn \
--source-port 25 \
-d $IPADDR --destination-port $UNPRIVPORTS -j ACCEPT
iptables -A OUTPUT -o $EXTERNAL_INTERFACE -p tcp \
-s $IPADDR --source-port $UNPRIVPORTS \
--destination-port 25 -j ACCEPT