Files
debian-cis/bin/hardening/iptables_outbound_established.sh
damien cavagnini 4be1a9d9e4 feat: add debian12 scripts
- iptables_loopback.sh 			-> 4.3.2.2
- iptables_rule_them_all.sh 		-> 4.3.2.4
- iptables_outbound_established.sh 	-> 4.3.2.3
- ip6tables_loopback.sh			-> 4.3.3.2
- ip6tables_outbound_established.sh	-> 4.3.3.3
- ip6tables_rule_them_all.sh		-> 4.3.3.4
- ip6tables_default_deny_policy.sh 	-> 4.3.3.1
2025-08-08 15:34:14 +02:00

87 lines
2.6 KiB
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Executable File

#!/bin/bash
# run-shellcheck
#
# CIS Debian Hardening
#
#
# Ensure iptables outbound and established connections are configured (Manual)
#
set -e # One error, it's over
set -u # One variable unset, it's over
# shellcheck disable=2034
HARDENING_LEVEL=2
# shellcheck disable=2034
DESCRIPTION="Ensure iptables outbound and established connections are configured"
PACKAGE="iptables"
# This function will be called if the script status is on enabled / audit mode
audit() {
is_pkg_installed "$PACKAGE"
if [ "$FNRET" -ne 0 ]; then
crit "$PACKAGE is not installed"
return
fi
INPUT_ESTABLISHED=1
OUTPUT_ESTABLISHED=1
local output_established_rules
if $SUDO_CMD iptables -S INPUT | grep ESTABLISHED >/dev/null 2>&1; then
INPUT_ESTABLISHED=0
ok "INPUT ESTABLISHED connections are allowed"
else
crit "INPUT ESTABLISHED connections are not allowed"
fi
if $SUDO_CMD iptables -S OUTPUT | grep state >/dev/null 2>&1; then
output_established_rules=$($SUDO_CMD iptables -S OUTPUT | grep state)
# shellcheck disable=2086
if grep ESTABLISHED <<<$output_established_rules >/dev/null && grep NEW <<<$output_established_rules >/dev/null; then
OUTPUT_ESTABLISHED=0
ok "OUTPUT NEW and ESTABLISHED connections are allowed"
else
crit "OUTPUT NEW and ESTABLISHED connections are not allowed"
fi
else
crit "OUTPUT NEW and ESTABLISHED connections are not allowed"
fi
}
# This function will be called if the script status is on enabled mode
apply() {
if [ "$INPUT_ESTABLISHED" -ne 0 ] || [ "$OUTPUT_ESTABLISHED" -ne 0 ]; then
info "Please review manually your outbound and established connection, and update them accordingly to your site policies"
fi
}
# This function will check config parameters required
check_config() {
:
}
# Source Root Dir Parameter
if [ -r /etc/default/cis-hardening ]; then
# shellcheck source=../../debian/default
. /etc/default/cis-hardening
fi
if [ -z "$CIS_LIB_DIR" ]; then
echo "There is no /etc/default/cis-hardening file nor cis-hardening directory in current environment."
echo "Cannot source CIS_LIB_DIR variable, aborting."
exit 128
fi
# Main function, will call the proper functions given the configuration (audit, enabled, disabled)
if [ -r "${CIS_LIB_DIR}"/main.sh ]; then
# shellcheck source=../../lib/main.sh
. "${CIS_LIB_DIR}"/main.sh
else
echo "Cannot find main.sh, have you correctly defined your root directory? Current value is $CIS_LIB_DIR in /etc/default/cis-hardening"
exit 128
fi