#!/bin/bash
#
 
RC_OK=0
RC_WARN=1
RC_CRIT=2
RC_UNKNOWN=3
 
CURL=/usr/bin/curl
 
usage()
{
    echo "usage: check_fritz -d -h hostname -f <function> [-w <warn>] [-c crit]"
    echo "    -d: enable debug output"
    echo "    -w: warn limit, depends on function"
    echo "    -c: critical limit, depends on function"
    echo "functions:"
    echo "    linkuptime = connection time in seconds."
    echo "    connection = connection status".
    echo "    ipaddress  = external ip address".
    echo "    upstream   = maximum upstream on current connection."
    echo "    downstream = maximum downstream on current connection."
    exit ${RC_UNKNOWN}
}
 
require_number()
{
    VAR=$1
    MSG=$2
 
    if [[ ! "${VAR}" =~ ^[0-9]+$ ]] ; then
        echo "ERROR - ${MSG} (${VAR})"
        exit ${RC_UNKNOWN}
    fi
}
 
require_ip()
{
    VAR=$1
    MSG=$2
    # echo "Check if ip address: $1"  
    if [[ ! "${VAR}" =~ ^[[:digit:]]{1,3}(\.[[:digit:]]{1,3}){3} ]] ; then
        echo "ERROR - ${MSG} (${VAR})"
        exit ${RC_UNKNOWN}
    fi
}
 
find_xml_value()
{
    XML=$1
    VAL=$2
 
    echo "${XML}" | grep "${VAL}" | sed "s/<${VAL}>\([^<]*\)<\/${VAL}>/\1/"
}
 
check_greater()
{
    VAL=$1
    WARN=$2
    CRIT=$3
    MSG=$4
 
    if [ ${VAL} -gt ${WARN} ] || [ ${WARN} -eq 0 ]; then
        echo "OK - ${MSG}"
        exit ${RC_OK}
    elif [ ${VAL} -gt ${CRIT} ] || [ ${CRIT} -eq 0 ]; then
        echo "WARNING - ${MSG}"
        exit ${RC_WARN}
    else
        echo "CRITICAL - ${MSG}"
        exit ${RC_CRIT}
    fi
}
 
HOSTNAME=192.168.178.1
PORT=49000
CHECK=linkuptime
DEBUG=0
WARN=0
CRIT=0
 
while getopts h:f:w:c:d OPTNAME; do
    case "${OPTNAME}" in
    h)
        HOSTNAME="${OPTARG}"
        ;;
    f)
        CHECK="${OPTARG}"
        ;;
    d)
        DEBUG=1
        ;;
    w)
        WARN="${OPTARG}"
        ;;
    c)
        CRIT="${OPTARG}"
        ;;
    *)
        usage
        ;;
    esac
done
 
case ${CHECK} in
    linkuptime|connection)
        VERB=GetStatusInfo
        URL=WANIPConn1
        NS=WANIPConnection
        ;;
    ipaddress)
        VERB=GetExternalIPAddress
        URL=WANIPConn1
        NS=WANIPConnection
        ;;
    downstream|upstream)
        VERB=GetAddonInfos
        URL=WANCommonIFC1
        NS=WANCommonInterfaceConfig
        ;;
    *)
        echo "ERROR - Unknown service check ${CHECK}"
        exit ${RC_UNKNOWN}
        ;;
esac
 
STATUS=`curl "http://${HOSTNAME}:${PORT}/igdupnp/control/${URL}" \
    -H "Content-Type: text/xml; charset="utf-8"" \
    -H "SoapAction:urn:schemas-upnp-org:service:${NS}:1#${VERB}" \
    -d "<?xml version='1.0' encoding='utf-8'?> <s:Envelope s:encodingStyle='http://schemas.xmlsoap.org/soap/encoding/' xmlns:s='http://schemas.xmlsoap.org/soap/envelope/'> <s:Body> <u:${VERB} xmlns:u="urn:schemas-upnp-org:service:${NS}:1" /> </s:Body> </s:Envelope>" \
    -s`
 
if [ "$?" -ne "0" ]; then
    echo "ERROR - Could not retrieve status from FRITZ!Box"
    exit ${RC_CRIT}
fi
 
if [ ${DEBUG} -eq 1 ]; then
    echo "DEBUG - Status:"
    echo "${STATUS}"
fi
 
case ${CHECK} in
linkuptime)
    UPTIME=$(find_xml_value "${STATUS}" NewUptime)
    require_number "${UPTIME}" "Could not parse uptime"
 
    HOURS=$((${UPTIME}/3600))
    MINUTES=$(((${UPTIME}-(${HOURS}*3600))/60))
    SECONDS=$((${UPTIME}-(${HOURS}*3600)-(${MINUTES}*60)))
    RESULT="Link uptime ${UPTIME} seconds (${HOURS}h ${MINUTES}m ${SECONDS}s)| uptime=${UPTIME} "
    check_greater ${UPTIME} 1 0 "${RESULT}"
    ;;
ipaddress)
    IPADDRESS=$(find_xml_value "${STATUS}" NewExternalIPAddress)
    require_ip "${IPADDRESS}" "Could not parse IP address"
    RESULT="The external IP address is: ${IPADDRESS}"
	echo ${RESULT}
    ;;
upstream)
    UPSTREAM=$(find_xml_value "${STATUS}" NewByteSendRate)
    require_number "${UPSTREAM}" "Could not parse upstream"
 
    KBUP=$((${UPSTREAM}/1024))
    RESULT="Upstream ${UPSTREAM} bits per second | Upstream=${UPSTREAM}"
    check_greater ${UPSTREAM} ${WARN} ${CRIT} "${RESULT} "
    ;;
downstream)
    DOWNSTREAM=$(find_xml_value "${STATUS}" NewByteReceiveRate)
    require_number "${DOWNSTREAM}" "Could not parse downstream"
    KBDOWN=$((${DOWNSTREAM}/1024))
    RESULT="Downstream ${DOWNSTREAM} bits per second | Downstream=${DOWNSTREAM}"
 
    check_greater ${DOWNSTREAM} ${WARN} ${CRIT} "${RESULT}"
    ;;
connection)
    STATE=$(find_xml_value "${STATUS}" NewConnectionStatus)
    case ${STATE} in
    Connected)
        echo "OK - Connected"
        exit ${RC_OK}
        ;;
    Connecting | Disconnected)
        echo "WARNING - Connection lost"
        exit ${RC_WARN}
        ;;
    *)
        echo "ERROR - Unknown connection state ${STATE}"
        exit ${RC_UNKNOWN}
        ;;
    esac
    ;;
*)
    echo "ERROR - Unknown service check ${CHECK}"
    exit ${RC_UNKNOWN}
esac