EH_HBHOptAfterDstOpt - check Hop-by-Hop Options Header position
Host and Router
EH_HBHOptAfterDstOpt.seq [-tooloption ...] -pkt EH_HBHOptAfterDstOpt.def -tooloption : v6eval tool option
None
Tester Target | | |-------------------------->| | Echo Request | | | | | |<--------------------------| | Neighbor Solicitation | | | | | |-------------------------->| | Neighbor Advertisement | | | | | |<--------------------------| | ICMP Error | | | v v
1. Send Echo Request 2. Wait ICMP Error or NS 3. If NS received then send NA, and wait ICMP Error again 4. Receive ICMP Error
Test Packet to Target Data is:
IPv6 Header Version = 6 Traffic Class = 0 FlowLabel = 0 PayloadLength = 32 NextHeader = 60 (Destination Options Header) SourceAddress = Tester Address DestinationAddress = Tester Address
Destination Options Header NextHeader = 0 (Hop-by-Hop Options Header) HeaderExtLength = 0 OptionType = 1 (PadN) OptDataLength = 4 pad = {0,0,0,0}
Hop-by-Hop Options Header NextHeader = 58 (ICMP) HeaderExtLength = 0 OptionType = 1 (PadN) OptDataLength = 4 pad = {0,0,0,0}
ICMP Echo Request Type = 128 (Echo Request) Code = 0 Checksum = (auto) Identifier = 0xffff SequenceNumber = 1 PayloadData = {1,2,3,4,5,6,7,8}
PASS: ICMP Error Received
IPv6 Header Version = 6 Traffic Class = 0 FlowLabel = 0 PayloadLength = 80 NextHeader = 58 (ICMP) SourceAddress = Target Address DestinationAddress = Tester Address
ICMP Error Type = 4 (Parameter Problem) Code = 1 (unrecognized Next Header type encountered) Checksum = (auto) Pointer = 40 (Offset to Next Header type) PayloadData = (Sent Packet)
RFC2460
4. IPv6 Extension Headers
If, as a result of processing a header, a node is required to proceed to the next header but the Next Header value in the current header is unrecognized by the node, it should discard the packet and send an ICMP Parameter Problem message to the source of the packet, with an ICMP Code value of 1 ("unrecognized Next Header type encountered") and the ICMP Pointer field containing the offset of the unrecognized value within the original packet. The same action should be taken if a node encounters a Next Header value of zero in any header other than an IPv6 header.
4.1 Extension Header Order
When more than one extension header is used in the same packet, it is recommended that those headers appear in the following order:
IPv6 header Hop-by-Hop Options header Destination Options header (note 1) Routing header Fragment header Authentication header (note 2) Encapsulating Security Payload header (note 2) Destination Options header (note 3) upper-layer header
IPv6 nodes must accept and attempt to process extension headers in any order and occurring any number of times in the same packet, except for the Hop-by-Hop Options header which is restricted to appear immediately after an IPv6 header only. Nonetheless, it is strongly advised that sources of IPv6 packets adhere to the above recommended order until and unless subsequent specifications revise that recommendation.
perldoc V6evalTool