NAME

  FH_1stOnly - check Fragment Reassembly (1st fragment only)

TARGET

  Host and Router

SYNOPSIS

  FH_1stOnly.seq [-tooloption ...] -pkt Fragment.def
    -tooloption : v6eval tool option

INITIALIZATION

  1. Ping to Target (create Neighbor Cache Entries, if not exist)
  2. Override Neighbor Cache Entries

TEST PROCEDURE

  Tester                      Target
    |                           |
    |-------------------------->|
    |   Echo Request (1st)      |
    |                           |
    |                           |
    |<--------------------------|
    |   ICMP Error              |
    |                           |
    |                           |
    v                           v

  1. Send Echo Request (1st fragment)
  2. Wait ICMP Error (timeout = 60 sec)
  3. Receive ICMP Error

  Echo Request Data (original) is:

        IPv6 Header
            Version            = 6
            Traffic Class      = 0
            FlowLabel          = 0
            PayloadLength      = 1032
            NextHeader         = 58 (ICMP)
            SourceAddress      = Tester Link Local Address
            DestinationAddress = Target Link Local Address

        ICMP Echo Request
            Type           = 128 (Echo Request)
            Code           = 0
            Checksum       = (auto)
            Identifier     = (auto)
            SequenceNumber = 0
            PayloadData    = data repeat{0x1, 512}
                             data repeat{0x2, 512}

  Echo Request Data (1st fragment) is:

        IPv6 Header
            Version            = 6
            Traffic Class      = 0
            FlowLabel          = 0
            PayloadLength      = 528
            NextHeader         = 44 (Fragment Header)
            SourceAddress      = Tester Link Local Address
            DestinationAddress = Target Link Local Address

        Fragment Header
            NextHeader         = 58 (ICMP)
            FragmentOffset     = 0
            MFlag              = 1
            Identification     = 32bit (Automatic generation)

        Payload
            data               = 520 octets from the head of ICMP Echo request

JUDGMENT

  PASS: ICMP Error Received

        IPv6 Header
            Version             = 6
            Traffic Class       = 0
            FlowLabel           = 0
            PayloadLength       = 16
            NextHeader          = 58 (ICMP)
            SourceAddress       = Target Link Local Address
            Destination Address = Tester Link Local Address

        ICMP Error
            Type           = 3 (Time Exceeded)
            Code           = 1 (fragment reassembly time exceeded)
            Checksum       = (auto)
            PayloadData    = (Echo Request)

REFERENCE

RFC2460

4.5 Fragment Header

                        :

   The following error conditions may arise when reassembling fragmented
   packets:

      If insufficient fragments are received to complete reassembly of a
      packet within 60 seconds of the reception of the first-arriving
      fragment of that packet, reassembly of that packet must be
      abandoned and all the fragments that have been received for that
      packet must be discarded.  If the first fragment (i.e., the one
      with a Fragment Offset of zero) has been received, an ICMP Time
      Exceeded -- Fragment Reassembly Time Exceeded message should be
      sent to the source of that fragment.



SEE ALSO

  perldoc V6evalTool