From: dv1tas <dv1tas@fbe50366-0c72-4402-a84b-5d246361dba7>
Date: Wed, 17 Jul 2013 08:15:19 +0000 (+0000)
Subject: In BPDUs use configured Hello_Time, not received from other bridge
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b14bad4888a5c3776a9fc9889e759dbd4d6c00ee;p=people%2Fms%2Fmstpd.git

In BPDUs use configured Hello_Time, not received from other bridge

>> RSTP-8.1
Tue Apr 30 13:33:08 2013: TEST_DESCRIPTION
If the physical connectivity of the network or management
parameters change, new spanning tree information will propagate
rapidly. Each Bridge accepts better information from any Bridge on
a LAN or revised information from the prior Designated Bridge for
that LAN. Updated Configuration Messages are transmitted through
Designated Ports, until the leaves of the Spanning Tree defined
by a new configuration are reached.
AND
The designatedTimes (17.19.5) for each Port, set equal to
the value of rootTimes, except for the Hello Time component,
which is set equal to BridgeTime's Hello Time
Tue Apr 30 13:33:08 2013: TEST_REFERENCE
IEEE Std 802.1D-2004 S17.9 P145
Changing Spanning Tree Information
IEEE Std 802.1D-2004 S17.21.25 P169
updtRolesTree()

Failure:

! Hello time in the received RST BPDU incorrectly set
! Expected Value : 2.000
! Received Value : 3.000

Reported-by: Satish Ashok <sashok@cumulusnetworks.com>
Signed-off-by: Vitalii Demianets <dvitasgs@gmail.com>
Reviewed-by: Satish Ashok <sashok@cumulusnetworks.com>


git-svn-id: svn://svn.code.sf.net/p/mstpd/code/trunk@58 fbe50366-0c72-4402-a84b-5d246361dba7
---

diff --git a/mstp.c b/mstp.c
index 3b3feea..dbf07ae 100644
--- a/mstp.c
+++ b/mstp.c
@@ -920,6 +920,11 @@ int MSTP_IN_set_cist_bridge_config(bridge_t *br, CIST_BridgeConfig *cfg)
             {
                 ptp->selected = false;
                 ptp->reselect = true;
+                /* TODO: change this when Hello_Time will be configurable
+                 *   per-port. For now, copy Bridge's Hello_Time
+                 *   to the port's Hello_Time.
+                 */
+                assign(ptp->portTimes.Hello_Time, br->Hello_Time);
             }
         }
     }
@@ -2090,10 +2095,18 @@ static void recordProposal(per_tree_port_t *ptp)
 /* 13.26.11 recordTimes */
 static void recordTimes(per_tree_port_t *ptp)
 {
+    /* 802.1Q-2005 and 802.1D-2004 both say that we have to copy
+     *   Hello_Time from msgTimes to portTimes.
+     * 802.1Q-2011, on the other hand, says that Hello_Time should be set
+     *   to the default here.
+     * As we have configurable Hello_Time, I choose the third option:
+     *   preserve the configured Hello_Time, It is in accordance with the
+     *   spirit of 802.1Q-2011, if we allow Hello_Time to be configurable.
+     */
+    __u8 prev_Hello_Time;
+    assign(prev_Hello_Time, ptp->portTimes.Hello_Time);
     assign(ptp->portTimes, ptp->msgTimes);
-
-    if(MIN_COMPAT_HELLO_TIME > ptp->portTimes.Hello_Time)
-        ptp->portTimes.Hello_Time = MIN_COMPAT_HELLO_TIME;
+    assign(ptp->portTimes.Hello_Time, prev_Hello_Time);
 }
 
 /* 13.24.s) + 17.19.7 of 802.1D : fdbFlush */
@@ -2643,6 +2656,13 @@ static void updtRolesTree(tree_t *tree)
 
         /* e) Set new designatedTimes */
         assign(ptp->designatedTimes, tree->rootTimes);
+        /* Keep the configured Hello_Time for the port.
+         * NOTE: this is in accordance with the spirit of 802.1D-2004.
+         *    Also, this does not contradict 802.1Q-2005(-2011), as in these
+         *    standards both designatedTimes and rootTimes structures
+         *    don't have Hello_Time member.
+         */
+        assign(ptp->designatedTimes.Hello_Time, ptp->portTimes.Hello_Time);
     }
 
     /* syncMaster */
diff --git a/mstp.h b/mstp.h
index 6443efc..2e7caad 100644
--- a/mstp.h
+++ b/mstp.h
@@ -106,9 +106,6 @@ typedef struct
     __be32 ExtRootPathCost;
 } port_priority_vector_t;
 
-/* 17.14 of 802.1D, Table 17-1 */
-#define MIN_COMPAT_HELLO_TIME   1
-
 typedef struct
 {
     __u8 remainingHops;