debian-cis/bin/hardening/4.2.1.6_remote_syslog-ng_acl.sh

#!/bin/bash

# run-shellcheck
#
# CIS Debian Hardening
#

#
# 4.2.1.6 Ensure remote syslog-ng messages are only accepted on designated log hosts. (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="Configure syslog to accept remote syslog messages only on designated log hosts."

PACKAGE='syslog-ng'
SYSLOG_BASEDIR='/etc/syslog-ng'
REMOTE_HOST=""
PATTERN='source[[:alnum:][:space:]*_*{]+(tcp|network|udp)[[:space:]]*\([[:space:]]*\"?[[:alnum:]\-.]+\"?.'

# This function will be called if the script status is on enabled / audit mode
audit() {
    is_pkg_installed "$PACKAGE"
    if [ "$FNRET" != 0 ]; then
        crit "$PACKAGE is not installed!"
    else
        FOUND=0
        FILES="$SYSLOG_BASEDIR/syslog-ng.conf $($SUDO_CMD find -L "$SYSLOG_BASEDIR"/conf.d/ -type f)"
        for FILE in $FILES; do
            does_pattern_exist_in_file_multiline "$FILE" "$PATTERN"
            if [ "$FNRET" = 0 ]; then
                FOUND=1
            fi
        done

        if [[ "$REMOTE_HOST" ]] && [[ "$REMOTE_HOST" != 'false' ]]; then
            info "This is the remote host, checking that it only accepts logs from specified zone"
            if [ "$FOUND" = 1 ]; then
                ok "$PATTERN is present in $FILES"
            else
                crit "$PATTERN is not present in $FILES"
            fi
        else
            info "This is the not the remote host checking that it doesn't accept remote logs"
            if [ "$FOUND" = 1 ]; then
                crit "$PATTERN is present in $FILES"
            else
                ok "$PATTERN is not present in $FILES"
            fi
        fi
    fi
}

# This function will be called if the script status is on enabled mode
apply() {
    is_pkg_installed "$PACKAGE"
    if [ "$FNRET" != 0 ]; then
        crit "$PACKAGE is not installed!"
    else
        FOUND=0
        FILES="$SYSLOG_BASEDIR/syslog-ng.conf $(find -L "$SYSLOG_BASEDIR"/conf.d/ -type f)"
        for FILE in $FILES; do
            does_pattern_exist_in_file_multiline "$FILE" "$PATTERN"
            if [ "$FNRET" = 0 ]; then
                FOUND=1
            fi
        done

        if [[ "$REMOTE_HOST" ]] && [[ "$REMOTE_HOST" != 'false' ]]; then
            info "This is the remote host, checking that it only accepts logs from specified zone"
            if [ "$FOUND" = 1 ]; then
                ok "$PATTERN is present in $FILES"
            else
                crit "$PATTERN is not present in $FILES, setup the machine to receive the logs"
            fi
        else
            info "This is the not the remote host checking that it doesn't accept remote logs"
            if [ "$FOUND" = 1 ]; then
                warn "$PATTERN is present in $FILES, "
            else
                ok "$PATTERN is not present in $FILES"
            fi
        fi
    fi
}

# This function will create the config file for this check with default values
create_config() {
    cat <<EOF
status=audit
SYSLOG_BASEDIR='/etc/syslog-ng'
# Put here if it's the remote host or not
REMOTE_HOST=false
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