feat: add debian12 scripts

- nftables_loopback_is_configured.sh 	-> 4.2.6
- nftables_established_connections.sh 	-> 4.2.7
- iptables_flushed_with_nftables.sh 	-> 4.2.3
- ufw_loopback_is_configured.sh 	-> 4.1.4
- ufw_outbound_connection.sh 		-> 4.1.5
- ufw_default_deny.sh 			-> 4.1.7
- ufw_rules_them_all.sh 		-> 4.1.6

bin/hardening/ufw_outbound_connection.sh

@@ -0,0 +1,85 @@
+#!/bin/bash
+
+# run-shellcheck
+#
+# CIS Debian Hardening
+#
+
+#
+# Ensure ufw outbound 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 ufw outbound connections are configured"
+UFW_RULES_FILE="/etc/ufw/user.rules"
+# variable defined in config file
+ALLOW_OUTBOUND_ALL=""
+
+# This function will be called if the script status is on enabled / audit mode
+audit() {
+    UFW_RULE_IS_VALID=1
+    # rules are saved in /etc/ufw/user.rules
+    # easier to parse than ufw output
+    if $SUDO_CMD grep "^[^#]*-[A,I].*output -o all -j ACCEPT" "$UFW_RULES_FILE" >/dev/null 2>&1; then
+        if [ "$ALLOW_OUTBOUND_ALL" -eq 0 ]; then
+            UFW_RULE_IS_VALID=0
+            ok "ufw output is allowed for all"
+        else
+            crit "ufw output is allowed for all, and ALLOW_OUTBOUND_ALL=1"
+        fi
+    else
+        if [ "$ALLOW_OUTBOUND_ALL" -eq 1 ]; then
+            UFW_RULE_IS_VALID=0
+            ok "ufw output is not allowed for all"
+        else
+            crit "ufw output is not allowed for all, and ALLOW_OUTBOUND_ALL=0"
+        fi
+    fi
+}
+
+# This function will be called if the script status is on enabled mode
+apply() {
+    if [ "$UFW_RULE_IS_VALID" -ne 0 ]; then
+        info "Please review the output rules according to your site policy, and update 'ALLOW_OUTBOUND_ALL' in configuration accordingly"
+    fi
+}
+
+create_config() {
+    cat <<EOF
+# shellcheck disable=2034
+status=audit
+# ALLOW_OUTBOUND_ALL=0 means true, we want the rule to be present
+# ALLOW_OUTBOUND_ALL=1 means false, we don't want the rule to be present
+ALLOW_OUTBOUND_ALL=0
+EOF
+}
+
+# This function will check config parameters required
+check_config() {
+    :
+}
+
+# Source Root Dir Parameter
+if [ -r /etc/default/cis-hardening ]; then
+    # shellcheck source=../../debian/default
+    . /etc/default/cis-hardening
+fi
+if [ -z "$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