NAME

hostRecvRaRFlag - Verifying that a RA sets a IsRouter flag true

TARGET

Host only

SYNOPSIS

  hostRecvRaRFlag.seq [-tooloption ...] -p hostRecvRaRFlag.def

INITIALIZATION

Create an neighbor cache entry for TN where a IsRouter flag is FALSE.
Set its state to REACHABLE.
Cache either TN's LLA or a bogus LLA.

Cache a LLA of TN

  TN                 NUT
  ----------------------
  State: NONCE (for TN)


  ==== echo-request ===>
        src=TN's link-local
        dst=NUT's link-local


  State: INCOMPLETE (for TN)


  <=== multicast NS ====
        src:NUT's link-local
        dst:solicited-node[TN's link-local]
        target=TN's link-local
        SLLA=NUT's LLA
        timeout: RETRANS_TIMER * MAX_MULTICAST_SOLICIT


  ==== solicited NA ===>
        src:TN's link
        dst:NUT's link-local
        R=0, S=1, O=1
        target=TN's link-local
        TLLA=TN's LLA


  State: REACHABLE (for TN)

Cache a bogus LLA

  TN                 NUT
  ----------------------
  State: NONCE (for TN)


  ==== echo-request ===>
        src=TN's link-local
        dst=NUT's link-local


  State: INCOMPLETE (for TN)


  <=== multicast NS ====
        src:NUT's link-local
        dst:solicited-node[TN's link-local]
        target=TN's link-local
        SLLA=NUT's LLA
        timeout: RETRANS_TIMER * MAX_MULTICAST_SOLICIT


  ==== solicited NA ===>
        src:TN's link
        dst:NUT's link-local
        R=0, S=1, O=1
        target=TN's link-local
        TLLA=a bogus LLA (0:0:0:0:a9:a9)


  State: REACHABLE (for TN)

TEST PROCEDURE

hostRecvRaRFlag verifies that a RA sets a IsRouter flag true.

  TN                 NUT
  ----------------------


  State: REACHABLE (for TN), NONCE(for X)


  ==== unsolicited RA ===>
       src=X's link-local
       dst=all-node
       M=0, O=0
       RouterLifetime=10
       ReachableTime=0
       RetransTimer=0
       w/ SLLA
       Prefix Option:
           L=1, A=1
           ValidLifetime=2592000
           PreferredLifetime=604800
           Prefix=3ffe:501:ffff:100::/64


  State: REACHABLE (for TN), STALE(for X)


  ==== solicited NA ===>
        src:X's link
        dst:NUT's link-local
        R=1, S=1, O=1
        target=X's link-local
        w/ TLLA


  Wait for 2 sec to ignore DAD NS


  State: REACHABLE (for TN, X)


  ==== echo-request ===>
       src=off-link global, but LLA is X's one
       dst=NUT's global


  <=== Judgment #1: echo-reply ====
       src=NUT's global
       dst=off-link global, but LLA is X's one


  ==== unsolicited RA ===>
       src=TN's link-local
       dst=all-node
       M=0, O=0
       RouterLifetime=600
       ReachableTime=0
       RetransTimer=0
       w/ or w/o SLLA
       Prefix Option:
           L=1, A=1
           ValidLifetime=2592000
           PreferredLifetime=604800
           Prefix=3ffe:501:ffff:100::/64


  State: REACHABLE/STALE (for TN), REACHABLE (for X)


  Wait (10 sec) for X's router lifetime to be expired


  ==== echo-request ===>
       src=off-link global, but LLA is TN's one
       dst=NUT's global


  <=== Judgment #3: echo-reply ====
       src=NUT's global
       dst=off-link global, but LLA is TN's one


  State: REACHABLE/DELAY (for TN), REACHABLE (for X)

JUDGMENT

  1. NUT throw an echo-reply to the default router (i.e. X).


  2. RA set IsRouter flag.

6.3.4.  Processing Received Router Advertisements


   After extracting information from the fixed part of the Router
   Advertisement message, the advertisement is scanned for valid
   options.  If the advertisement contains a Source Link-Layer Address
   option the link-layer address SHOULD be recorded in the Neighbor
   Cache entry for the router (creating an entry if necessary) and the
   IsRouter flag in the Neighbor Cache entry MUST be set to TRUE.
   If no Source Link-Layer Address is included, but a corresponding Neighbor
   Cache entry exists, its IsRouter flag MUST be set to TRUE.  The
   IsRouter flag is used by Neighbor Unreachability Detection to
   determine when a router changes to being a host (i.e., no longer
   capable of forwarding packets).  If a Neighbor Cache entry is created
   for the router its reachability state MUST be set to STALE as
   specified in Section 7.3.3.  If a cache entry already exists and is
   updated with a different link-layer address the reachability state
   MUST also be set to STALE.

  ============+===========+===============================
  RA received by the NUT  | NUT's Neighbor Cache State
  ------------+-----------+---------+---------------------
  Destination | SLLA      | Current | New
  ============+===========+=========+=====================
  all-node    | none      | 0       | 1
  ------------+-----------+---------+---------------------
  all-node    | same      | 0       | 1
  ------------+-----------+---------+---------------------
  all-node    | different | 0       | 1
  ============+===========+=========+=====================


  3. NUT throw an echo-reply to NUT instead of X.

TERMINATION

  Send the following RAs to clear the Default Router List:
  - RA (src: TN) with RouterLifetime=0
  - RA (src: X)  with RouterLifetime=0

NOTE

  The test does not invoke any remote command.