#!/usr/bin/perl
#
# $Copyright$
#
# $TAHI: ct/spec/HL_ZeroToRouter.seq,v 1.23 2003/04/23 12:44:27 ozoe Exp $
#
######################################################################
BEGIN {
	$V6evalTool::TestVersion = '$Name:  $';
}

use V6evalTool;

if ($V6evalTool::NutDef{Type} ne 'router') {
    vLogHTML("This test is for the router only<BR>");
    exit $V6evalTool::exitRouterOnly;
}

%pktdesc = (
	echo_request_to_link0	=> 'Send Echo Request to Link0  (Hop Limit 0)',
	icmp_type3_code0	=> 'Recv ICMP Error at Link0 (Time Exceeded, hop limit exceeded in transit)',
	icmp_type3_code0_link1	=> 'Recv ICMP Error at Link1 (Time Exceeded, hop limit exceeded in transit)',
	ns_from_link0		=> 'Recv Neighbor Solicitation from Link0 (Global Address)',
	na_to_link0		=> 'Send Neighbor Advertisement to Link0 (Global Address)',
);

$IF0 = Link0;

vCapture($IF0);

vSend($IF0, echo_request_to_link0);

%ret = vRecv($IF0, 5, 0, 0, ns_from_link0, icmp_type3_code0, icmp_type3_code0_link1);
if ($ret{status} != 0) {
	vLogHTML('<FONT COLOR="#FF0000">NG</FONT>');
	exit $V6evalTool::exitFail;
}

if ($ret{recvFrame} eq 'ns_from_link0') {

	vSend($IF0, na_to_link0);

	%ret = vRecv($IF0, 5, 0, 0, icmp_type3_code0, icmp_type3_code0_link1);
	if ($ret{status} != 0) {
		vLogHTML('<FONT COLOR="#FF0000">NG</FONT>');
		exit $V6evalTool::exitFail;
	}
}
if ($ret{recvFrame} eq 'icmp_type3_code0') {
	vLogHTML('OK');
	exit $V6evalTool::exitPass;
}
if ($ret{recvFrame} eq 'icmp_type3_code0_link1') {
	vLogHTML('OK');
	exit $V6evalTool::exitPass;
}

vLogHTML('<FONT COLOR="#FF0000">NG</FONT>');
exit $V6evalTool::exitFail;

######################################################################
__END__

=head1 NAME

  HL_ZeroToRouter - check Hop Limit 0 to Router

=head1 TARGET

  Router

=head1 SYNOPSIS

=begin html
<PRE>
  <A HREF="./HL_ZeroToRouter.seq">HL_ZeroToRouter.seq</A> [-tooloption ...] -pkt <A HREF="./HL_ZeroToRouter.def">HL_ZeroToRouter.def</A>
    -tooloption : v6eval tool option
  See also <A HREF="./IH_Router.def">IH_Router.def</A>
</PRE>

=end html

=head1 INITIALIZATION

  None

=head1 TEST PROCEDURE

  Tester                      Target                      Tester
              (Link0)                     (Link1)
    |                           |                           |
    |-------------------------->|                           |
    |   Echo Request to Link0   |                           |
    |                           |     (no forwarding)       |
    |                           |                           |
    |<--------------------------|                           |
    |   Neighbor Solicitation   |                           |
    |                           |                           |
    |-------------------------->|                           |
    |   Neighbor Advertisement  |                           |
    |                           |                           |
    |<--------------------------|                           |
    |    ICMP Error at Link0    |                           |
    |            or             |                           |
    |    ICMP Error at Link1    |                           |
    |                           |                           |
    v                           v                           v

  1. Send Echo Request to Link0
  2. Wait ICMP Error or NS from Link0
  3. If NS received then send NA to Link0, and wait ICMP Error again
  4. Receive ICMP Error

  Echo Request to Link0 Data is:

        IPv6 Header
            Version            = 6
            Traffic Class      = 0
            FlowLabel          = 0
            PayloadLength      = 16
            NextHeader         = 58 (ICMP)
            HopLimit           = 0
            SourceAddress      = Tester Global Address (Link0)
            DestinationAddress = Tester Global Address (Link1)

        ICMP Echo Request
            Type           = 128 (Echo Request)
            Code           = 0
            Checksum       = (auto)
            Identifier     = 0xffff
            SequenceNumber = 1
            PayloadData    = {1,2,3,4,5,6,7,8}

=head1 JUDGMENT

  PASS: ICMP Error at Link0 Received

        IPv6 Header
            Version             = 6
            Traffic Class       = 0
            FlowLabel           = 0
            PayloadLength       = 16
            NextHeader          = 58 (ICMP)
            SourceAddress      = Target Global Address (Link0)
            DestinationAddress = Tester Global Address (Link0)

        ICMP Error
            Type           = 3 (Time Exceeded)
            Code           = 0 (hop limit exceeded in transit)
            Checksum       = (auto)
            PayloadData    = (Echo Request)

  PASS: ICMP Error at Link1 Received

        IPv6 Header
            Version             = 6
            Traffic Class       = 0
            FlowLabel           = 0
            PayloadLength       = 16
            NextHeader          = 58 (ICMP)
            SourceAddress      = Target Global Address (Link1)
            DestinationAddress = Tester Global Address (Link0)

        ICMP Error
            Type           = 3 (Time Exceeded)
            Code           = 0 (hop limit exceeded in transit)
            Checksum       = (auto)
            PayloadData    = (Echo Request)

=head1 REFERENCE

RFC2460

3.  IPv6 Header Format

   Hop Limit            8-bit unsigned integer.  Decremented by 1 by
                        each node that forwards the packet. The packet

RFC2463

3.3 Time Exceeded Message

   ICMPv6 Fields:

   Type           3

   Code           0 - hop limit exceeded in transit

   Description

=begin html
<PRE>
   <B>If a router receives a packet with a Hop Limit of zero, or a router
   decrements a packet's Hop Limit to zero, it MUST discard the packet
   and send an ICMPv6 Time Exceeded message with Code 0 to the source of
   the packet.  This indicates either a routing loop or too small an
   initial Hop Limit value.</B>
</PRE>

=end html

=head1 SEE ALSO

  perldoc V6evalTool

=cut