feat: add debian12 scripts

- nftables_is_enabled.sh -> 4.2.9 - nftables_has_table.sh -> 4.2.4 - nftables_has_base_chains.sh -> 4.2.5 - nftables_rules_permanent.sh -> 4.2.10
2025-08-04 22:31:16 +02:00 · 2025-08-01 16:20:58 +02:00
parent 0cf11ca4cf
commit dfd3773129
9 changed files with 419 additions and 1 deletions
--- a/bin/hardening/nftables_rules_permanent.sh
+++ b/bin/hardening/nftables_rules_permanent.sh
@@ -0,0 +1,111 @@
+#!/bin/bash
+
+# run-shellcheck
+#
+# CIS Debian Hardening
+#
+
+#
+# Ensure nftables rules are permanent (Automated)
+#
+
+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 nftables rules are permanent"
+NFTABLES_CONF="/etc/nftables.conf"
+
+# default to "/etc/nftables.rules"
+# May be changed in config, see "create_config" below
+NFTABLES_RULES=""
+
+# This function will be called if the script status is on enabled / audit mode
+audit() {
+    NFTABLES_INCLUDE=1
+    NFTABLES_INCLUDE_INPUT=1
+    NFTABLES_INCLUDE_OUTPUT=1
+    NFTABLES_INCLUDE_FORWARD=1
+    # the CIS recommendation is to have one or many nftables rules outside nftables.conf
+    if grep -E '^\s*include' "$NFTABLES_CONF" >/dev/null; then
+        NFTABLES_INCLUDE=0
+        ok "There is an included file in $NFTABLES_CONF"
+
+        # shellcheck disable=2046
+        if [ $(awk '/hook input/,/}/' $(awk '$1 ~ /^\s*include/ { gsub("\"","",$2);print $2 }' $NFTABLES_CONF) | wc -l) -gt 0 ]; then
+            NFTABLES_INCLUDE_INPUT=0
+            ok "nftables input is configured to be persistent"
+        else
+            crit "nftables input is not configured to be persistent"
+        fi
+
+        # shellcheck disable=2046
+        if [ $(awk '/hook forward/,/}/' $(awk '$1 ~ /^\s*include/ { gsub("\"","",$2);print $2 }' $NFTABLES_CONF) | wc -l) -gt 0 ]; then
+            NFTABLES_INCLUDE_FORWARD=0
+            ok "nftables forward is configured to be persistent"
+        else
+            crit "nftables forward is not configured to be persistent"
+        fi
+
+        # shellcheck disable=2046
+        if [ $(awk '/hook output/,/}/' $(awk '$1 ~ /^\s*include/ { gsub("\"","",$2);print $2 }' $NFTABLES_CONF) | wc -l) -gt 0 ]; then
+            NFTABLES_INCLUDE_OUTPUT=0
+            ok "nftables output is configured to be persistent"
+        else
+            crit "nftables output is not configured to be persistent"
+        fi
+
+    else
+        crit "There is no 'include' in $NFTABLES_CONF"
+    fi
+}
+
+# This function will be called if the script status is on enabled mode
+apply() {
+    audit
+    if [ "$NFTABLES_INCLUDE" -ne 0 ]; then
+        add_end_of_file "$NFTABLES_CONF" "include \"$NFTABLES_RULES\""
+    fi
+
+    if [ "$NFTABLES_INCLUDE_INPUT" -ne 0 ] || [ "$NFTABLES_INCLUDE_FORWARD" -ne 0 ] || [ "$NFTABLES_INCLUDE_OUTPUT" -ne 0 ]; then
+        info "some basic chains are not persisted in $NFTABLES_RULES, please review them manually"
+    fi
+
+}
+
+create_config() {
+    cat <<EOF
+# shellcheck disable=2034
+status=audit
+# Put here the nftables rules file for persistent rules
+NFTABLES_RULES="/etc/nftables.rules"
+EOF
+}
+
+# This function will check config parameters required
+check_config() {
+    :
+}
+
+# Source Root Dir Parameter
+if [ -r /etc/default/cis-hardening ]; then
+    # shellcheck source=../../debian/default
+    . /etc/default/cis-hardening
+fi
+
+if [ -z "$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