debian-cis/bin/hardening/99.3.3.3_hosts_deny.sh

#!/bin/bash

# run-shellcheck
#
# CIS Debian Hardening
#

#
# 99.3.3.3 Ensure /etc/hosts.deny is configured (Not Scored)
#

set -e # One error, it's over
set -u # One variable unset, it's over

# shellcheck disable=2034
HARDENING_LEVEL=3
# shellcheck disable=2034
DESCRIPTION="Create /etc/hosts.deny ."

FILE='/etc/hosts.deny'
PATTERN='ALL: ALL'

# This function will be called if the script status is on enabled / audit mode
audit() {
    does_file_exist "$FILE"
    if [ "$FNRET" != 0 ]; then
        crit "$FILE does not exist"
    else
        ok "$FILE exists, checking configuration"
        does_pattern_exist_in_file "$FILE" "$PATTERN"
        if [ "$FNRET" != 0 ]; then
            crit "$PATTERN is not present in $FILE, we have to deny everything"
        else
            ok "$PATTERN is present in $FILE"
        fi
    fi
}

# This function will be called if the script status is on enabled mode
apply() {
    does_file_exist "$FILE"
    if [ "$FNRET" != 0 ]; then
        warn "$FILE does not exist, creating it"
        touch "$FILE"
    else
        ok "$FILE exists"
    fi
    does_pattern_exist_in_file "$FILE" "$PATTERN"
    if [ "$FNRET" != 0 ]; then
        crit "$PATTERN is not present in $FILE, we have to deny everything"
        add_end_of_file "$FILE" "$PATTERN"
        warn "YOU MAY HAVE CUT YOUR ACCESS, CHECK BEFORE DISCONNECTING"
    else
        ok "$PATTERN is present in $FILE"
    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_ROOT_DIR" ]; then
    echo "There is no /etc/default/cis-hardening file nor cis-hardening directory in current environment."
    echo "Cannot source CIS_ROOT_DIR variable, aborting."
    exit 128
fi

# Main function, will call the proper functions given the configuration (audit, enabled, disabled)
if [ -r "$CIS_ROOT_DIR"/lib/main.sh ]; then
    # shellcheck source=../../lib/main.sh
    . "$CIS_ROOT_DIR"/lib/main.sh
else
    echo "Cannot find main.sh, have you correctly defined your root directory? Current value is $CIS_ROOT_DIR in /etc/default/cis-hardening"
    exit 128
fi