tcpdump/tcpdump-qeth

81 lines
2.4 KiB
Perl

#!/usr/bin/perl
# (C)2002 by IBM Corporation, published under terms of the GPL V2
# Author: Holger Smolinski <smolinsk@de.ibm.com>
# this file is a wrapper around tcpdump, which provides the capability
# for debugging qeth and/or HiperSocket(TM) network interfaces under
# Linux for S/390 and zSeries. tcpdump Syntax is preserved.
# Bugs: When the input pipe ends the process is not stopped.
use Getopt::Std;
my $incmd,$outcmd;
getopts ("adeflnNOpqRStuvxXc:C:F:i:m:r:s:T:w:E:",\%options);
# Check which options to replace for the reader process
if ( defined($options{'r'}) ) {
$incmd = "cat $options{'r'}";
$filter_out = 1;
} else {
$incmd = "tcpdump -l -w -";
$filter_out = 0;
if ( defined($options{'i'}) ) {
$incmd .= " -i ".$options{'i'};
delete $options{'i'}; # remove -i option from option list
}
foreach $key (@ARGV) {
$incmd .= " $key";
}
}
$outcmd = "tcpdump -r -";
# Rebuild arglist for the writer process
delete $options{'r'}; # remove -r option from option list
foreach $key (keys %options) {
if ((index "adeflnNOpqRStuvxX",$key) >= 0 ) {
$outcmd .= " -$key";
} else {
$outcmd .= " -$key $options{$key}";
}
if ( $filter_out == 1 ) {
foreach $key (@ARGV) {
$outcmd .= " $key";
}
}
}
open READER,"$incmd|" or die "Cannot spawn reader command $incmd";
open WRITER,"|$outcmd" or die "Cannot spawn writer command $outcmd";
sysread READER,$filehdr,24 or die "Cannot read file header";
($magic,$version_major,$version_minor,$thiszone,$sigfigs,$snaplen,$linktype) =
unpack("ISSIIII",$filehdr);
$snaplen += 14;
$filehdr = pack ("ISSIIII",($magic,$version_major,$version_minor,$thiszone,$sigfigs,$snaplen,$linktype));
syswrite WRITER,$filehdr,24;
$etherheaderip6 = pack ("IIIS",(0,0,0,0x8dd));
$etherheaderip4 = pack ("IIIS",(0,0,0,0x800));
while ( 1 ) {
$hdrd = 0;
do {$hdrd += sysread READER, $pkthdr, 16-$hdrd, $hdrd; } while ($hdrd < 16);
($seconds,$usecs,$caplen,$len) = unpack ("IIII",$pkthdr);
$hdrd = 0;
do {$hdrd += sysread READER, $packet,$caplen-$hdrd, $hdrd; } while ($hdrd < $caplen);
$paktype = unpack("C",$packet);
if ( $paktype & 0xf0 == 0x60 ) {
$caplen += 14;
$len += 14;
$header = $etehrheaderip6;
} elsif ($paktype >= 0x45 && $paktype <= 0x4f ) {
$caplen += 14;
$len += 14;
$header = $etherheaderip4;
} else {
$header = "";
}
$pkthdr = pack ("IIII",($seconds,$usecs,$caplen,$len));
syswrite WRITER,"$pkthdr$header$packet",16+$caplen;
}