package/base-files/files/bin/ipcalc.sh

   1 #!/bin/sh
   2
   3 awk -f /usr/lib/common.awk -f - $* <<EOF
   4 BEGIN {
   5         slpos=index(ARGV[1],"/")
   6         if (slpos == 0) {
   7                 ipaddr=ip2int(ARGV[1])
   8                 netmask=ip2int(ARGV[2])
   9         } else {
  10                 ipaddr=ip2int(substr(ARGV[1],0,slpos-1))
  11                 netmask=compl(2**(32-int(substr(ARGV[1],slpos+1)))-1)
  12                 ARGV[4]=ARGV[3]
  13                 ARGV[3]=ARGV[2]
  14         }
  15
  16         network=and(ipaddr,netmask)
  17         broadcast=or(network,compl(netmask))
  18
  19         start=or(network,and(ip2int(ARGV[3]),compl(netmask)))
  20         limit=network+1
  21         if (start<limit) start=limit
  22
  23         end=start+ARGV[4]
  24         limit=or(network,compl(netmask))-1
  25         if (end>limit) end=limit
  26
  27         print "IP="int2ip(ipaddr)
  28         print "NETMASK="int2ip(netmask)
  29         print "BROADCAST="int2ip(broadcast)
  30         print "NETWORK="int2ip(network)
  31         print "PREFIX="32-bitcount(compl(netmask))
  32
  33         # range calculations:
  34         # ipcalc <ip> <netmask> <start> <num>
  35
  36         if (ARGC > 3) {
  37                 print "START="int2ip(start)
  38                 print "END="int2ip(end)
  39         }
  40 }
  41 EOF