mirror of
https://github.com/BlackLight/Snort_AIPreproc.git
synced 2024-12-26 03:05:11 +01:00
132 lines
2.7 KiB
Perl
Executable file
132 lines
2.7 KiB
Perl
Executable file
#!/usr/bin/perl
|
|
|
|
use strict;
|
|
use warnings;
|
|
use MIME::Base64;
|
|
use Env qw(QUERY_STRING DOCUMENT_ROOT);
|
|
|
|
sub url_decode {
|
|
my $str = shift;
|
|
$str =~ s/%([A-Fa-f0-9]{2})/pack('C', hex($1))/seg;;
|
|
return $str;
|
|
}
|
|
|
|
sub print_pcap_header {
|
|
my $out = shift;
|
|
|
|
# pcap magic_number
|
|
print $out pack ( 'L', 0xa1b2c3d4 );
|
|
|
|
# pcap version_major
|
|
print $out pack ( 'S', 0x2 );
|
|
|
|
# pcap version_minor
|
|
print $out pack ( 'S', 0x4 );
|
|
|
|
# pcap thiszone
|
|
print $out pack ( 'l', 0x0 );
|
|
|
|
# pcap sigfigs
|
|
print $out pack ( 'L', 0x0 );
|
|
|
|
# pcap snaplen
|
|
print $out pack ( 'L', 0xffff );
|
|
|
|
# pcap network
|
|
print $out pack ( 'L', 0x1 );
|
|
}
|
|
|
|
sub print_packet {
|
|
my ( $out, $packet ) = @_;
|
|
|
|
# ts_sec
|
|
print $out pack ( 'L', $packet->{'time'} );
|
|
|
|
# ts_usec
|
|
print $out pack ( 'L', 0x0 );
|
|
|
|
my $pkt_data = decode_base64 ( url_decode ( $packet->{'content'} ));
|
|
my $hex = unpack ( 'H*', $pkt_data );
|
|
my @pairs = $hex =~ /([a-fA-F0-9]{2})/g;
|
|
|
|
# If this is not an IP packet, trust what the client has told you as packet length
|
|
if (( $pairs[0] ne '45' && $pairs[1] ne '00' ) || ( @pairs < 5 ))
|
|
{
|
|
# incl_len
|
|
print $out pack ( 'L', $packet->{'length'} + 12 );
|
|
|
|
# orig_len
|
|
print $out pack ( 'L', $packet->{'length'} + 12 );
|
|
} else {
|
|
# Otherwise, the length of the packet is the one specified in the IP header
|
|
my $length = hex ( $pairs[2].$pairs[3] );
|
|
|
|
# If the lengths differ (IP length and actual length of the stream received), pad
|
|
# the end of the packet with some 0's so that its length matches the one
|
|
# specified in the IP header
|
|
if ( $length > ( length ( $hex ) / 2 ))
|
|
{
|
|
my $pad_size = $length - ( length ( $hex ) / 2 );
|
|
$hex .= '00' for ( 0..$pad_size-1 );
|
|
$pkt_data = pack ( 'H*', $hex );
|
|
}
|
|
|
|
# Add the length of a pseudo-ethernet header
|
|
$length += 14;
|
|
|
|
# incl_len
|
|
print $out pack ( 'L', $length );
|
|
|
|
# orig_len
|
|
print $out pack ( 'L', $length );
|
|
}
|
|
|
|
# pseudo ethernet header
|
|
print $out pack ( 'H*', 0 x24 );
|
|
|
|
# ethernet type (IP)
|
|
print $out pack ( 'S', 0x8 );
|
|
|
|
# packet content
|
|
print $out $pkt_data;
|
|
}
|
|
|
|
$QUERY_STRING =~ /packets=([0-9]+)/;
|
|
my $packets_num = $1;
|
|
my %packets = ();
|
|
|
|
for ( my $i=0; $i < $packets_num; $i++ )
|
|
{
|
|
$QUERY_STRING =~ /packet_len$i=([0-9]+)/;
|
|
my $length = $1;
|
|
|
|
$QUERY_STRING =~ /time$i=([0-9]+)/;
|
|
my $time = $1;
|
|
|
|
$QUERY_STRING =~ /packet$i=(.+?)(&|$)/;
|
|
my $content = $1;
|
|
|
|
$packets{$i} = {
|
|
'length' => $length,
|
|
'time' => $time,
|
|
'content' => $content
|
|
};
|
|
}
|
|
|
|
print "Content-Type: application/pcap\n\n";
|
|
|
|
# open my $out, "> $DOCUMENT_ROOT/out.pcap";
|
|
open my $out, ">&STDOUT";
|
|
binmode $out;
|
|
print_pcap_header $out;
|
|
|
|
for ( my $i=0; $i < $packets_num; $i++ )
|
|
{
|
|
print_packet $out, $packets{$i};
|
|
}
|
|
|
|
close $out;
|
|
|
|
# print "Content-Type: text/html\\n\\n";
|
|
# print "<meta http-equiv=\\"refresh\\" content=\\"0;url=/out.pcap\\">\\n";
|
|
|