#!/usr/local/bin/perl
#Encode IP addresses for fr/er packet trace files.
#The output format equals the input format, except that the IP
#addresses are encoded and consist of a 12 bit wide encoded network number
#field, followed by a 20 bit wide encoded host number field.

$infile=$ARGV[0];
open(infile,$infile) || die;

while(read(infile,$record,24)){
 $count++;
 ($tsec,$tusec,$src,$dst,$misc,$ports)=unpack(L6,$record);

 $srcn = $src & 0xffffff00; $srch = $src & 0x000000ff;
 if($src < 0xc0000000) {$srcn = $src & 0xffff0000;$srch = $src & 0x0000ffff;}
 if($src < 0x80000000) {$srcn = $src & 0xff000000;$srch = $src & 0x00ffffff;}
 if(!$id{$srcn,-1})    {$id{$srcn,-1}    = ++$netcount;}
 if(!$id{$srcn,$srch}) {$id{$srcn,$srch} = ++$hstcount{$srcn};}
 $src=($id{$srcn,-1}<<16) + $id{$srcn,$srch};

 $dstn = $dst & 0xffffff00; $dsth = $dst & 0x000000ff;
 if($dst < 0xc0000000) {$dstn = $dst & 0xffff0000;$dsth = $dst & 0x0000ffff;}
 if($dst < 0x80000000) {$dstn = $dst & 0xff000000;$dsth = $dst & 0x00ffffff;}
 if(!$id{$dstn,-1})    {$id{$dstn,-1}    = ++$netcount;}
 if(!$id{$dstn,$dsth}) {$id{$dstn,$dsth} = ++$hstcount{$dstn};}
 $dst=($id{$dstn,-1}<<16) + $id{$dstn,$dsth};

 $record = pack("L6", $tsec, $tusec, $src, $dst, $misc, $ports);
 syswrite(stdout,$record,24) || die;
}

close(infile); close(stdout);
printf "Processed $count records.\n";