From 81a948b4d8923924e53ae2dd28a0262c9fde0ed3 Mon Sep 17 00:00:00 2001 From: Jonathan Hui Date: Fri, 27 May 2022 13:15:58 -0700 Subject: [PATCH] [mle] evaluate neighbor links before upgrade to router (#7765) OpenThread only etablishes links when the link margin is above a certain threshold, to help ensure that links in the routing topology are stable. However, if a device has no existing links to neighboring routers above threshold, then upgrading to a router is useless and disruptive. This commit adds a check to ensure there is at least one neighbor above the link margin threshold before upgrading to a router. --- src/core/thread/mle_router.cpp | 37 ++++++- src/core/thread/mle_router.hpp | 1 + tests/scripts/thread-cert/Makefile.am | 2 + .../thread-cert/test_router_upgrade.py | 99 +++++++++++++++++++ 4 files changed, 138 insertions(+), 1 deletion(-) create mode 100755 tests/scripts/thread-cert/test_router_upgrade.py diff --git a/src/core/thread/mle_router.cpp b/src/core/thread/mle_router.cpp index 69c10b58c..813f1a2a1 100644 --- a/src/core/thread/mle_router.cpp +++ b/src/core/thread/mle_router.cpp @@ -1764,6 +1764,41 @@ exit: LogProcessError(kTypeParentRequest, error); } +bool MleRouter::HasNeighborWithGoodLinkQuality(void) const +{ + bool haveNeighbor = true; + uint8_t linkMargin; + + linkMargin = + LinkQualityInfo::ConvertRssToLinkMargin(Get().GetNoiseFloor(), mParent.GetLinkInfo().GetLastRss()); + + if (linkMargin >= OPENTHREAD_CONFIG_MLE_LINK_REQUEST_MARGIN_MIN) + { + ExitNow(); + } + + for (Router &router : Get().Iterate()) + { + if (!router.IsStateValid()) + { + continue; + } + + linkMargin = + LinkQualityInfo::ConvertRssToLinkMargin(Get().GetNoiseFloor(), router.GetLinkInfo().GetLastRss()); + + if (linkMargin >= OPENTHREAD_CONFIG_MLE_LINK_REQUEST_MARGIN_MIN) + { + ExitNow(); + } + } + + haveNeighbor = false; + +exit: + return haveNeighbor; +} + void MleRouter::HandleTimeTick(void) { bool routerStateUpdate = false; @@ -1833,7 +1868,7 @@ void MleRouter::HandleTimeTick(void) case kRoleChild: if (routerStateUpdate) { - if (mRouterTable.GetActiveRouterCount() < mRouterUpgradeThreshold) + if (mRouterTable.GetActiveRouterCount() < mRouterUpgradeThreshold && HasNeighborWithGoodLinkQuality()) { // upgrade to Router IgnoreError(BecomeRouter(ThreadStatusTlv::kTooFewRouters)); diff --git a/src/core/thread/mle_router.hpp b/src/core/thread/mle_router.hpp index 0ae422ed2..3ccd231fb 100644 --- a/src/core/thread/mle_router.hpp +++ b/src/core/thread/mle_router.hpp @@ -633,6 +633,7 @@ private: Error UpdateChildAddresses(const Message &aMessage, uint16_t aOffset, Child &aChild); void UpdateRoutes(const RouteTlv &aRoute, uint8_t aRouterId); bool UpdateLinkQualityOut(const RouteTlv &aRoute, Router &aNeighbor, bool &aResetAdvInterval); + bool HasNeighborWithGoodLinkQuality(void) const; static void HandleAddressSolicitResponse(void * aContext, otMessage * aMessage, diff --git a/tests/scripts/thread-cert/Makefile.am b/tests/scripts/thread-cert/Makefile.am index 1b517e190..4b115e902 100644 --- a/tests/scripts/thread-cert/Makefile.am +++ b/tests/scripts/thread-cert/Makefile.am @@ -184,6 +184,7 @@ EXTRA_DIST = \ test_reset.py \ test_route_table.py \ test_router_reattach.py \ + test_router_upgrade.py \ test_service.py \ test_set_mliid.py \ test_srp_auto_start_mode.py \ @@ -258,6 +259,7 @@ check_SCRIPTS = \ test_reset.py \ test_route_table.py \ test_router_reattach.py \ + test_router_upgrade.py \ test_service.py \ test_srp_auto_start_mode.py \ test_srp_client_remove_host.py \ diff --git a/tests/scripts/thread-cert/test_router_upgrade.py b/tests/scripts/thread-cert/test_router_upgrade.py new file mode 100755 index 000000000..bb1374fea --- /dev/null +++ b/tests/scripts/thread-cert/test_router_upgrade.py @@ -0,0 +1,99 @@ +#!/usr/bin/env python3 +# +# Copyright (c) 2022, The OpenThread Authors. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# 3. Neither the name of the copyright holder nor the +# names of its contributors may be used to endorse or promote products +# derived from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE +# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. +# + +import unittest + +import config +import mle +import network_layer +import thread_cert + +LEADER = 1 +REED = 2 + +RSSI_LOW = -95 +RSSI_HIGH = -45 + +ROUTER_UPGRADE_DELAY = 150 + +# Test Purpose and Description: +# ----------------------------- +# The purpose of this test case is to show that a REED does not +# upgrade to router if it does not have a neighbor with link margin +# above threshold. +# +# Test Topology: +# ------------- +# Leader +# | +# REED +# +# DUT Types: +# ---------- +# Leader +# REED + + +class TestRouterUpgrade(thread_cert.TestCase): + USE_MESSAGE_FACTORY = False + + TOPOLOGY = { + LEADER: { + 'name': 'LEADER', + 'mode': 'rdn', + 'allowlist': [REED] + }, + REED: { + 'name': 'REED', + 'mode': 'rdn', + 'allowlist': [LEADER] + }, + } + + def test(self): + self.nodes[LEADER].start() + self.simulator.go(5) + self.assertEqual(self.nodes[LEADER].get_state(), 'leader') + + self.nodes[REED].add_allowlist(self.nodes[LEADER].get_addr64(), rssi=RSSI_LOW) + self.nodes[REED].enable_allowlist() + + self.nodes[REED].start() + self.simulator.go(ROUTER_UPGRADE_DELAY) + self.assertEqual(self.nodes[REED].get_state(), 'child') + + self.nodes[REED].add_allowlist(self.nodes[LEADER].get_addr64(), rssi=RSSI_HIGH) + self.nodes[REED].enable_allowlist() + + self.simulator.go(ROUTER_UPGRADE_DELAY) + self.assertEqual(self.nodes[REED].get_state(), 'router') + + +if __name__ == '__main__': + unittest.main()