comment on

# extract the source IP addr into dotted quad form my($source) = sprintf("%d.%d.%d.%d", ord( substr($packet, $src_ip, 1) ), ord( substr($packet, $src_ip+1, 1) ), ord( substr($packet, $src_ip+2, 1) ), ord( substr($packet, $src_ip+3, 1) )); # extract the destination IP addr into dotted quad form my($destination) = sprintf("%d.%d.%d.%d", ord( substr($packet, $dst_ip, 1) ), ord( substr($packet, $dst_ip+1, 1) ), ord( substr($packet, $dst_ip+2, 1) ), ord( substr($packet, $dst_ip+3, 1) )); #the above part is directly taken from "hacking linux exposed" (sorry +but couldn't figure out this part)
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An easier way to do that is through the Socket module:

use Socket;
# extract the source IP addr into dotted quad form
my $source = inet_ntoa substr $packet, $src_ip, 4;

# extract the destination IP addr into dotted quad form
my $destination = inet_ntoa substr $packet, $dst_ip, 4;
[download]

In reply to Re: my first packet sniffer in perl by jwkrahn
in thread my first packet sniffer in perl by hnd

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