Shell Programming and Scripting

222.104.193.5/32
222.106.31.112/32
222.106.31.123/32
222.126.13.224/32
222.191.251.186/32

222.104.193.5  222.104.193.5
222.106.31.112  222.106.31.112
222.106.31.123  222.106.31.123
222.126.13.224  222.126.13.231
222.191.251.186  222.191.251.186

#!/usr/local/bin/gawk

# Library with various ip manipulation functions
# convert ip ranges to CIDR notation

function range2cidr(ipStart, ipEnd, bits, mask, newip) {
    bits = 1
    mask = 1
    while (bits < 32) {
        newip = or(ipStart, mask)
        if ((newip>ipEnd) || ((lshift(rshift(ipStart,bits),bits)) != ipStart)) {
           bits--
           mask = rshift(mask,1)
           break
        }
        bits++
        mask = lshift(mask,1)+1
    }
    newip = or(ipStart, mask)
    bits = 32 - bits
    result = dec2ip(ipStart) "/" bits
    if (newip < ipEnd) result = range2cidr(newip + 1, ipEnd)
    return result
}

# convert dotted quads to long decimal ip
#       int ip2dec("192.168.0.15")
#
function ip2dec(ip, slice) {
        split(ip, slice, ".")
        return (slice[1] * 2^24) + (slice[2] * 2^16) + (slice[3] * 2^8) + slice[4]
}

# convert decimal long ip to dotted quads
#       str dec2ip(1171259392)
#
function dec2ip(dec, ip, quad) {
        for (i=3; i>=1; i--) {
                quad = 256^i
                ip = ip int(dec/quad) "."
                dec = dec%quad
        }
        return ip dec
}

function sanitize(ip) {
        split(ip, slice, ".")
        return slice[1]/1 "." slice[2]/1 "." slice[3]/1 "." slice[4]/1
}

BEGIN{
        FS=" | - "
}

# sanitize ip's
{$1 = sanitize($1); $2 = sanitize($2)}

{print range2cidr(ip2dec($1), ip2dec($2))}

END {print ""}

real    0m12.081s
user    0m10.202s
sys     0m0.967s

function range2cidr(ipStart, ipEnd, bits, mask, newip) {
    bits = 1
    mask = 1
    while (bits < 32) {
        newip = or(ipStart, mask)
        if ((newip>ipEnd) || ((lshift(rshift(ipStart,bits),bits)) != ipStart)) {
           bits--
           mask = rshift(mask,1)
           break
        }
        bits++
        mask = lshift(mask,1)+1
    }
    newip = or(ipStart, mask)
    bits = 32 - bits
    result = dec2ip(ipStart) "/" bits
    if (newip < ipEnd) result = range2cidr(newip + 1, ipEnd)
    return result
}

# convert dotted quads to long decimal ip
#       int ip2dec("192.168.0.15")
#
function ip2dec(ip, slice) {
        split(ip, slice, ".")
        return (slice[1] * 2^24) + (slice[2] * 2^16) + (slice[3] * 2^8) + slice[4]
}

# convert decimal long ip to dotted quads
#       str dec2ip(1171259392)
#
function dec2ip(dec, ip, quad) {
        for (i=3; i>=1; i--) {
                quad = 256^i
                ip = ip int(dec/quad) "."
                dec = dec%quad
        }
        return ip dec
}

function sanitize(ip) {
        split(ip, slice, ".")
        return slice[1]/1 "." slice[2]/1 "." slice[3]/1 "." slice[4]/1
}

BEGIN{
        FS="[- :]"
}

# sanitize ip's
!/^#/ && NF {$1 = sanitize($(NF-1)); $2 = sanitize($NF)}

!/^#/ && NF {print range2cidr(ip2dec($(NF-1)), ip2dec($NF))}

END {print ""}