debian-cis/bin/hardening/2.2.1.4_configure_ntp.sh

#!/bin/bash

# run-shellcheck
#
# CIS Debian Hardening
#

#
# 2.2.1.2 Ensure ntp is configured (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="Configure Network Time Protocol (ntp). Check restrict parameters and ntp daemon runs ad unprivileged user."
# shellcheck disable=2034
HARDENING_EXCEPTION=ntp

PACKAGE='ntp'
NTP_CONF_DEFAULT_PATTERN='^restrict -4 default (kod nomodify notrap nopeer noquery|kod notrap nomodify nopeer noquery|ignore)'
NTP_CONF_FILE='/etc/ntp.conf'
NTP_INIT_PATTERN='RUNASUSER=ntp'
NTP_INIT_FILE='/etc/init.d/ntp'

# This function will be called if the script status is on enabled / audit mode
audit() {
    does_pattern_exist_in_file "$NTP_CONF_FILE" "$NTP_CONF_DEFAULT_PATTERN"
    if [ "$FNRET" != 0 ]; then
        crit "$NTP_CONF_DEFAULT_PATTERN not found in $NTP_CONF_FILE"
    else
        ok "$NTP_CONF_DEFAULT_PATTERN found in $NTP_CONF_FILE"
    fi
    does_pattern_exist_in_file "$NTP_INIT_FILE" "^$NTP_INIT_PATTERN"
    if [ "$FNRET" != 0 ]; then
        crit "$NTP_INIT_PATTERN not found in $NTP_INIT_FILE"
    else
        ok "$NTP_INIT_PATTERN found in $NTP_INIT_FILE"
    fi
}

# This function will be called if the script status is on enabled mode
apply() {
    is_pkg_installed "$PACKAGE"
    if [ "$FNRET" = 0 ]; then
        ok "$PACKAGE is installed"
    else
        crit "$PACKAGE is absent, installing it"
        apt_install "$PACKAGE"
        info "Checking $PACKAGE configuration"
    fi
    does_pattern_exist_in_file "$NTP_CONF_FILE" "$NTP_CONF_DEFAULT_PATTERN"
    if [ "$FNRET" != 0 ]; then
        warn "$NTP_CONF_DEFAULT_PATTERN not found in $NTP_CONF_FILE, adding it"
        backup_file "$NTP_CONF_FILE"
        add_end_of_file "$NTP_CONF_FILE" "restrict -4 default kod notrap nomodify nopeer noquery"
    else
        ok "$NTP_CONF_DEFAULT_PATTERN found in $NTP_CONF_FILE"
    fi
    does_pattern_exist_in_file "$NTP_INIT_FILE" "^$NTP_INIT_PATTERN"
    if [ "$FNRET" != 0 ]; then
        warn "$NTP_INIT_PATTERN not found in $NTP_INIT_FILE, adding it"
        backup_file "$NTP_INIT_FILE"
        add_line_file_before_pattern "$NTP_INIT_FILE" "$NTP_INIT_PATTERN" "^UGID"
    else
        ok "$NTP_INIT_PATTERN found in $NTP_INIT_FILE"
    fi
}

# This function will check config parameters required
check_config() {
    is_pkg_installed "$PACKAGE"
    if [ "$FNRET" != 0 ]; then
        warn "$PACKAGE is not installed, not handling configuration"
        exit 2
    fi
}

# 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