NAME

  DupCookieEchoBadMD5.seq - Duplicate COOKIE-ECHO chunk is received with wrong MD5 signature


PURPOSE

  To check that if COOKIE-ECHO chunk is received with wrong MD5 signature
  when a TCB exists then the endpoint should silent discard the COOKIE-ECHO
  chunk.


SYNOPSIS

  ./DupCookieEchoBadMD5.seq [-tooloption ...] -pkt ./DupCookieEchoBadMD5.def
    -tooloption : v6eval tool option
  See Also: ../common/STD_PKT_COMMON.def
            ../common/SCTP_COMMON.def


PRE-TEST CONDITION

  Association is established between endpoint A and B. Arrange the data
  in endpoint A such that COOKIE-ECHO message with invalid secret key
  is sent to B.


TEST PROCEDURE

  Endpoint A                           Endpoint B                ULP
  (ESTABLISHED)                        (ESTABLISHED)
  COOKIE-ECHO   ----------------->      Silently discarded
  (with wrong MD5 signature)
  TEST DESCRIPTION:
  1. Send duplicate COOKIE-ECHO message with wrong MD5 signature. 
  2. Check A: COOKIE-ECHO message is silently discarded 
  3. Check B: Existing association is not disturbed.


NOTE

  None


REFERENCE

  RFC 4960
  5.2.4.  Handle a COOKIE ECHO when a TCB Exists
    When a COOKIE ECHO chunk is received by an endpoint in any state for
    an existing association (i.e., not in the CLOSED state) the following
    rules shall be applied:
    1)  Compute a MAC as described in step 1 of Section 5.1.5,
    2)  Authenticate the State Cookie as described in step 2 of Section
        5.1.5 (this is case C or D above).