[mle] invalidate EID-to-RLOC cache entries while removing a neighbor

Signed-off-by: Duda, Lukasz <[email protected]>

src/core/thread/address_resolver.cpp

@@ -97,17 +97,28 @@ exit:
     return error;
 }
 
-void AddressResolver::Remove(uint8_t routerId)
+void AddressResolver::Remove(uint8_t aRouterId)
 {
     for (int i = 0; i < kCacheEntries; i++)
     {
-        if (Mle::Mle::GetRouterId(mCache[i].mRloc16) == routerId)
+        if (Mle::Mle::GetRouterId(mCache[i].mRloc16) == aRouterId)
         {
             InvalidateCacheEntry(mCache[i], kReasonRemovingRouterId);
         }
     }
 }
 
+void AddressResolver::Remove(uint16_t aRloc16)
+{
+    for (int i = 0; i < kCacheEntries; i++)
+    {
+        if (mCache[i].mRloc16 == aRloc16)
+        {
+            InvalidateCacheEntry(mCache[i], kReasonRemovingRloc16);
+        }
+    }
+}
+
 AddressResolver::Cache *AddressResolver::NewCacheEntry(void)
 {
     Cache *rval = NULL;
@@ -156,6 +167,10 @@ const char *AddressResolver::ConvertInvalidationReasonToString(InvalidationReaso
         str = "removing router id";
         break;
 
+    case kReasonRemovingRloc16:
+        str = "removing rloc16";
+        break;
+
     case kReasonReceivedIcmpDstUnreachNoRoute:
         str = "received icmp no route";
         break;

src/core/thread/address_resolver.hpp

@@ -94,7 +94,15 @@ public:
     otError GetEntry(uint8_t aIndex, otEidCacheEntry &aEntry) const;
 
     /**
-     * This method removes a Router ID from the EID-to-RLOC cache.
+     * This method removes the EID-to-RLOC cache entries corresponding to an RLOC16.
+     *
+     * @param[in]  aRloc16  The RLOC16 address.
+     *
+     */
+    void Remove(uint16_t aRloc16);
+
+    /**
+     * This method removes all EID-to-RLOC cache entries assossiated with a Router ID.
      *
      * @param[in]  aRouterId  The Router ID.
      *
@@ -169,6 +177,7 @@ private:
     enum InvalidationReason
     {
         kReasonRemovingRouterId,
+        kReasonRemovingRloc16,
         kReasonReceivedIcmpDstUnreachNoRoute,
         kReasonEvictingForNewEntry,
     };

src/core/thread/mle_router.cpp

@@ -3244,6 +3244,13 @@ otError MleRouter::RemoveNeighbor(Neighbor &aNeighbor)
             aNeighbor.SetState(Neighbor::kStateInvalid);
             netif.GetMeshForwarder().UpdateIndirectMessages();
             netif.GetNetworkDataLeader().SendServerDataNotification(aNeighbor.GetRloc16());
+
+            if (aNeighbor.GetDeviceMode() & ModeTlv::kModeFFD)
+            {
+                // Clear all EID-to-RLOC entries assossiated with the child.
+                netif.GetAddressResolver().Remove(aNeighbor.GetRloc16());
+            }
+
             RemoveStoredChild(aNeighbor.GetRloc16());
         }
         else if ((aNeighbor.GetState() == Neighbor::kStateValid) && IsActiveRouter(aNeighbor.GetRloc16()))
@@ -3270,6 +3277,9 @@ otError MleRouter::RemoveNeighbor(Neighbor &aNeighbor)
             if (routerToRemove.GetNextHop() == kInvalidRouterId)
             {
                 ResetAdvertiseInterval();
+
+                // Clear all EID-to-RLOC entries assossiated with the router.
+                netif.GetAddressResolver().Remove(GetRouterId(aNeighbor.GetRloc16()));
             }
         }