If unknown port role is received in RSTP version, treat the RSTP BPDU as a STP Config...

If unknown port role is received in RSTP version, treat the RSTP BPDU as a STP Config BPDU instead and set the role to be designated role

Ixia RSTP ANVL Failure:

>> RSTP-1.2
Tue Apr 30 13:28:03 2013: TEST_DESCRIPTION
Quick test to verify that DUT transmits RST BPDU from each port.
The Unknown value of Port Role cannot be generated by a valid
implementation; however, this value is accepted on receipt.
(NOTE: The DUT will treat this RST-BPDU as a Configuration BPDU)
(Test to verify that the incoming RST BPDU with Unknown Port role
plays a role in the calculation of Active Spanning Tree)

Tue Apr 30 13:28:03 2013: TEST_REFERENCE
NEGATIVE
IEEE Std 802.1D-2004 S9.2.9 Page 61

Verification:

  DUT: Treat the received RST BPDU as CONFIG BPDU
  DUT: Select <bestBridgeID> B1 as Root Bridge
  ANVL: Listen (for upto 3 * <configBridgeHelloTime> seconds) on <DIface-1>
  DUT: Send RST BPDU
  Root Identifier field set to <bestBridgeID> B1

  Failure:
  ! Received RST BPDU doesn't contain expected
  ! Root Indentifier : 0 / 02:02:00:00:00:01Tue Apr 30 13:28:13 2013:

Signed-off-by: Satish Ashok <sashok@cumulusnetworks.com>
Signed-off-by: Vitalii Demianets <dvitasgs@gmail.com>
git-svn-id: svn://svn.code.sf.net/p/mstpd/code/trunk@40 fbe50366-0c72-4402-a84b-5d246361dba7