#!/usr/bin/env perl
use warnings;
use strict;  

# Description: Networking for Unix systems

our $VERSION = '1.3';

# Linux network module for sysinfo client
# Author: R. W. Rodolico
# Date:   2016-04-08

# module to get network interface information for Linux systems
# assumes ifconfig is on the system and executable by the user
# NOTE: this takes the ifconfig output and parses it, so changes to 
#       this output invalidates this module
#
# 2018-05-20 RWR
# Modified to use ip vs ifconfig, and changed the regex's.
# kept the original ifconfig code but commented it out

BEGIN {
   push @INC, shift;
}

use library;

exit 1 unless lc ( &getOperatingSystem() ) eq 'linux';

my $command = &validCommandOnSystem('ip');

exit 1 unless $command;

my $CATEGORY = 'network';

# get list of all interfaces except lo
my @interfaces = `$command -o a s | cut -d' ' -f2 | sort | uniq | grep -v 'lo'`;
chomp @interfaces;

my $ipv4Regex = '\b(?:[0-9]{1,3}\.){3}[0-9]{1,3}\b';
my $ipv6Regex = '(([a-f0-9]+):{1,2})+[a-z0-9]+';

foreach my $if ( @interfaces ) {
   foreach my $line ( `$command address show $if` ) {
      # mtu
      if ( $line =~ m/mtu\s+(\d+)/i ) {
         print "$CATEGORY\t$if\tmtu\t$1\n";
      # MAC
      } elsif ( $line =~ m/((([a-f0-9]{2}):){5}[a-f0-9]+)/i ) {
         print "$CATEGORY\t$if\tmac\t$1\n";
      # inet 6
      } elsif ( $line =~ m"inet6\s*((([a-f0-9]+):{1,2})+[a-z0-9]+)/(\d{1,2})"i ) {
         print "$CATEGORY\t$if\tip6address\t$1\n";
         print "$CATEGORY\t$if\tip6networkbits\t$4\n";
      # inet 4
      } elsif ( $line =~ m"inet.*($ipv4Regex)/(\d{2})" ) {
         print "$CATEGORY\t$if\taddress\t$1\n";
         print "$CATEGORY\t$if\tnetmask\t$2\n";
      }
   }
}

# this is the original code, in case we ever need it again

## eth1      Link encap:Ethernet  HWaddr 00:16:3E:1F:EF:4F
#my $regexHWADDR = 'hwaddr[^0-9a-f:]+([0-9a-f:]+)[^0-9a-f:]';
## inet addr:10.110.110.2  Bcast:10.110.110.255  Mask:255.255.255.0
#my $regexINET = 'inet addr:\s*([0-9.]+)[^0-9].*mask:([0-9.]+)';
## inet6 addr: fe80::216:3eff:fe1f:ef4f/64 Scope:Link
#my $regexINET6 = 'inet6 addr: ([0-9a-f:]+)\/([0-9]+)[^0-9]';
## UP LOOPBACK RUNNING  MTU:16436  Metric:1
#my $regexMTU = 'mtu:([0-9]+)[^0-9]';
#my $temp = qx/$command/;
#my @temp = split( "\n", $temp );
#my $currentIF;
#while ( @temp ) {
#   my $line = shift @temp;
#   next unless $line;
#   if ( $line =~ m/^([^ ]+) /) { # if the first character is not a space, starting new entry
#      $currentIF = $1;
#      if ( $line =~ m/$regexHWADDR/i ) {
#         print "$CATEGORY\t$currentIF\tmac\t$1\n";
#      } else {
#         print "$CATEGORY\t$currentIF\tmac\tunknown\n";
#      }
#   } elsif ( $line =~ m/$regexINET/i ) {
#      print "$CATEGORY\t$currentIF\taddress\t$1\n";
#      print "$CATEGORY\t$currentIF\tnetmask\t$2\n";
#   } elsif ( $line =~ m/$regexINET6/i )  {
#      print "$CATEGORY\t$currentIF\tip6address\t$1\n";
#      print "$CATEGORY\t$currentIF\tip6networkbits\t$2\n";
#   } elsif ( $line =~ m/$regexMTU/i )  {
#      print "$CATEGORY\t$currentIF\tmtu\t$1\n";
#   }
#}
#