1#!/usr/bin/perl -w
2#
3# CDDL HEADER START
4#
5# The contents of this file are subject to the terms of the
6# Common Development and Distribution License (the "License").
7# You may not use this file except in compliance with the License.
8#
9# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10# or http://www.opensolaris.org/os/licensing.
11# See the License for the specific language governing permissions
12# and limitations under the License.
13#
14# When distributing Covered Code, include this CDDL HEADER in each
15# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16# If applicable, add the following below this CDDL HEADER, with the
17# fields enclosed by brackets "[]" replaced with your own identifying
18# information: Portions Copyright [yyyy] [name of copyright owner]
19#
20# CDDL HEADER END
21#
22
23#
24# Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
25# Use is subject to license terms.
26#
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#
30# get.ipv6remote.pl
31#
32# Find an IPv6 reachable remote host using both ifconfig(1M) and ping(1M).
33# Print the local address and the remote address, or print nothing if either
34# no IPv6 interfaces or remote hosts were found.  (Remote IPv6 testing is
35# considered optional, and so not finding another IPv6 host is not an error
36# state we need to log.)  Exit status is 0 if a host was found.
37#
38
39use strict;
40use IO::Socket;
41
42my $MAXHOSTS = 32;			# max hosts to scan
43my $TIMEOUT = 3;			# connection timeout
44my $MULTICAST = "FF02::1";		# IPv6 multicast address
45
46#
47# Determine local IP address
48#
49my $local = "";
50my $remote = "";
51my $interf = "";
52my %Local;
53my %Addr;
54my $up;
55open IFCONFIG, '/sbin/ifconfig -a inet6 |'
56    or die "Couldn't run ifconfig: $!\n";
57while (<IFCONFIG>) {
58	next if /^lo/;
59
60	# "UP" is always printed first (see print_flags() in ifconfig.c):
61	$up = 1 if /^[a-z].*<UP,/;
62	$up = 0 if /^[a-z].*<,/;
63
64	if (m:(\S+\d+)\: :) {
65		$interf = $1;
66	}
67
68	# assume output is "inet6 ...":
69	if (m:inet6 (\S+) :) {
70		my $addr = $1;
71                $Local{$addr} = 1;
72                $Addr{$interf} = $addr;
73		$up = 0;
74		$interf = "";
75	}
76}
77close IFCONFIG;
78
79#
80# Find the first remote host that responds to an icmp echo,
81# which isn't a local address. Try each IPv6-enabled interface.
82#
83foreach $interf (split(' ', `ifconfig -l -u inet6`)) {
84	next if $interf =~ /lo[0-9]+/;
85	open PING, "/sbin/ping6 -n -s 56 -c $MAXHOSTS $MULTICAST\%$interf |" or next;
86	while (<PING>) {
87		if (/bytes from (.*), / and not defined $Local{$1}) {
88			$remote = $1;
89			$local = $Addr{$interf};
90			last;
91		}
92	}
93}
94close PING;
95exit 2 if $remote eq "";
96
97print "$local $remote\n";
98