ip functions (check whether ip is in given range e.g.)

iptools.bash

# ip functions (check whether ip is in given range e.g.)
# collected from https://github.com/caquino/bash-functions/blob/master/network-lib


iscidr () {
    [[ ${1} =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\/?[0-9]{1,2}?$ ]] && echo $1
}

inet_ntoa () {
    [[ ${1} =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]] || return 255
    IFS=".";set - ${1};unset IFS
    local OCT1 OCT2 OCT3 OCT4
    OCT1=$(($1<<24));OCT2=$(($2<<16));OCT3=$(($3<<8));OCT4=$4
    echo $(($OCT1+$OCT2+$OCT3+$OCT4))
}

inet_aton () {
    [[ ${1} =~ ^[0-9]+$ ]] || return 255
    ADDRESS=${1}
    OCT4=$((${ADDRESS} % 256));ADDRESS=$((${ADDRESS}-${OCT4}));ADDRESS=$((${ADDRESS}/256))
    OCT3=$((${ADDRESS} % 256));ADDRESS=$((${ADDRESS}-${OCT3}));ADDRESS=$((${ADDRESS}/256))
    OCT2=$((${ADDRESS} % 256));ADDRESS=$((${ADDRESS}-${OCT2}));ADDRESS=$((${ADDRESS}/256))
    OCT1=$((${ADDRESS} % 256))
    echo "${OCT1}.${OCT2}.${OCT3}.${OCT4}"
}

isipinrange () {
    [[ ${1} =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]] || return 255
    [[ ${2} =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\/?[0-9]{1,2}?$ ]] || return 255
    NETWORK=$(inet_ntoa ${2%%/*})
    BITMASK=${2##*/}
    BITMASK=$((~((1<<(32 - $BITMASK))-1)))
    IPDEC=$(inet_ntoa ${1})
    IPNET=$((${IPDEC}&${BITMASK}))
    [[ ${IPNET} == ${NETWORK} ]] && return 0
    return 1
}