1 /*
2  *  Copyright (c) 2019, The OpenThread Authors.
3  *  All rights reserved.
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5  *  Redistribution and use in source and binary forms, with or without
6  *  modification, are permitted provided that the following conditions are met:
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8  *     notice, this list of conditions and the following disclaimer.
9  *  2. Redistributions in binary form must reproduce the above copyright
10  *     notice, this list of conditions and the following disclaimer in the
11  *     documentation and/or other materials provided with the distribution.
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13  *     names of its contributors may be used to endorse or promote products
14  *     derived from this software without specific prior written permission.
15  *
16  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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27  */
28 
29 /**
30  * @file
31  *   This file implements Primary Backbone Router service management in the Thread Network.
32  */
33 
34 #include "bbr_leader.hpp"
35 
36 #if (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
37 
38 #include "common/locator_getters.hpp"
39 #include "instance/instance.hpp"
40 
41 namespace ot {
42 namespace BackboneRouter {
43 
44 RegisterLogModule("BbrLeader");
45 
Leader(Instance & aInstance)46 Leader::Leader(Instance &aInstance)
47     : InstanceLocator(aInstance)
48 {
49     Reset();
50 }
51 
Reset(void)52 void Leader::Reset(void)
53 {
54     // Invalid server short address indicates no available Backbone Router service in the Thread Network.
55     mConfig.mServer16 = Mac::kShortAddrInvalid;
56 
57     // Domain Prefix Length 0 indicates no available Domain Prefix in the Thread network.
58     mDomainPrefix.SetLength(0);
59 }
60 
GetConfig(Config & aConfig) const61 Error Leader::GetConfig(Config &aConfig) const
62 {
63     Error error = kErrorNone;
64 
65     VerifyOrExit(HasPrimary(), error = kErrorNotFound);
66 
67     aConfig = mConfig;
68 
69 exit:
70     return error;
71 }
72 
GetServiceId(uint8_t & aServiceId) const73 Error Leader::GetServiceId(uint8_t &aServiceId) const
74 {
75     Error error = kErrorNone;
76 
77     VerifyOrExit(HasPrimary(), error = kErrorNotFound);
78     error = Get<NetworkData::Service::Manager>().GetServiceId<NetworkData::Service::BackboneRouter>(
79         /* aServerStable */ true, aServiceId);
80 
81 exit:
82     return error;
83 }
84 
85 #if OT_SHOULD_LOG_AT(OT_LOG_LEVEL_INFO)
86 
LogBackboneRouterPrimary(State aState,const Config & aConfig) const87 void Leader::LogBackboneRouterPrimary(State aState, const Config &aConfig) const
88 {
89     OT_UNUSED_VARIABLE(aConfig);
90 
91     LogInfo("PBBR state: %s", StateToString(aState));
92 
93     if (aState != kStateRemoved && aState != kStateNone)
94     {
95         LogInfo("Rloc16:0x%4x, seqno:%u, delay:%u, timeout:%lu", aConfig.mServer16, aConfig.mSequenceNumber,
96                 aConfig.mReregistrationDelay, ToUlong(aConfig.mMlrTimeout));
97     }
98 }
99 
StateToString(State aState)100 const char *Leader::StateToString(State aState)
101 {
102     static const char *const kStateStrings[] = {
103         "None",            //  (0) kStateNone
104         "Added",           //  (1) kStateAdded
105         "Removed",         //  (2) kStateRemoved
106         "Rereg triggered", //  (3) kStateToTriggerRereg
107         "Refreshed",       //  (4) kStateRefreshed
108         "Unchanged",       //  (5) kStateUnchanged
109     };
110 
111     static_assert(0 == kStateNone, "kStateNone value is incorrect");
112     static_assert(1 == kStateAdded, "kStateAdded value is incorrect");
113     static_assert(2 == kStateRemoved, "kStateRemoved value is incorrect");
114     static_assert(3 == kStateToTriggerRereg, "kStateToTriggerRereg value is incorrect");
115     static_assert(4 == kStateRefreshed, "kStateRefreshed value is incorrect");
116     static_assert(5 == kStateUnchanged, "kStateUnchanged value is incorrect");
117 
118     return kStateStrings[aState];
119 }
120 
DomainPrefixEventToString(DomainPrefixEvent aEvent)121 const char *Leader::DomainPrefixEventToString(DomainPrefixEvent aEvent)
122 {
123     static const char *const kEventStrings[] = {
124         "Added",     // (0) kDomainPrefixAdded
125         "Removed",   // (1) kDomainPrefixRemoved
126         "Refreshed", // (2) kDomainPrefixRefreshed
127         "Unchanged", // (3) kDomainPrefixUnchanged
128     };
129 
130     static_assert(0 == kDomainPrefixAdded, "kDomainPrefixAdded value is incorrect");
131     static_assert(1 == kDomainPrefixRemoved, "kDomainPrefixRemoved value is incorrect");
132     static_assert(2 == kDomainPrefixRefreshed, "kDomainPrefixRefreshed value is incorrect");
133     static_assert(3 == kDomainPrefixUnchanged, "kDomainPrefixUnchanged value is incorrect");
134 
135     return kEventStrings[aEvent];
136 }
137 
138 #endif // OT_SHOULD_LOG_AT(OT_LOG_LEVEL_INFO)
139 
Update(void)140 void Leader::Update(void)
141 {
142     UpdateBackboneRouterPrimary();
143     UpdateDomainPrefixConfig();
144 }
145 
UpdateBackboneRouterPrimary(void)146 void Leader::UpdateBackboneRouterPrimary(void)
147 {
148     Config config;
149     State  state;
150 
151     Get<NetworkData::Service::Manager>().GetBackboneRouterPrimary(config);
152 
153     if (config.mServer16 != mConfig.mServer16)
154     {
155         if (config.mServer16 == Mac::kShortAddrInvalid)
156         {
157             state = kStateRemoved;
158         }
159         else if (mConfig.mServer16 == Mac::kShortAddrInvalid)
160         {
161             state = kStateAdded;
162         }
163         else
164         {
165             // Short Address of PBBR changes.
166             state = kStateToTriggerRereg;
167         }
168     }
169     else if (config.mServer16 == Mac::kShortAddrInvalid)
170     {
171         // If no Primary all the time.
172         state = kStateNone;
173     }
174     else if (config.mSequenceNumber != mConfig.mSequenceNumber)
175     {
176         state = kStateToTriggerRereg;
177     }
178     else if (config.mReregistrationDelay != mConfig.mReregistrationDelay || config.mMlrTimeout != mConfig.mMlrTimeout)
179     {
180         state = kStateRefreshed;
181     }
182     else
183     {
184         state = kStateUnchanged;
185     }
186 
187     // Restrain the range of MLR timeout to be always valid
188     if (config.mServer16 != Mac::kShortAddrInvalid)
189     {
190         uint32_t origTimeout = config.mMlrTimeout;
191 
192         config.mMlrTimeout = Clamp(config.mMlrTimeout, kMinMlrTimeout, kMaxMlrTimeout);
193 
194         if (config.mMlrTimeout != origTimeout)
195         {
196             LogNote("Leader MLR Timeout is normalized from %lu to %lu", ToUlong(origTimeout),
197                     ToUlong(config.mMlrTimeout));
198         }
199     }
200 
201     mConfig = config;
202     LogBackboneRouterPrimary(state, mConfig);
203 
204 #if OPENTHREAD_FTD && OPENTHREAD_CONFIG_BACKBONE_ROUTER_ENABLE
205     Get<BackboneRouter::Local>().HandleBackboneRouterPrimaryUpdate(state, mConfig);
206 #endif
207 
208 #if OPENTHREAD_CONFIG_MLR_ENABLE || (OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_MLR_ENABLE)
209     Get<MlrManager>().HandleBackboneRouterPrimaryUpdate(state, mConfig);
210 #endif
211 
212 #if OPENTHREAD_CONFIG_DUA_ENABLE || (OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_DUA_ENABLE)
213     Get<DuaManager>().HandleBackboneRouterPrimaryUpdate(state, mConfig);
214 #endif
215 }
216 
UpdateDomainPrefixConfig(void)217 void Leader::UpdateDomainPrefixConfig(void)
218 {
219     NetworkData::Iterator           iterator = NetworkData::kIteratorInit;
220     NetworkData::OnMeshPrefixConfig config;
221     DomainPrefixEvent               event;
222     bool                            found = false;
223 
224     while (Get<NetworkData::Leader>().GetNextOnMeshPrefix(iterator, config) == kErrorNone)
225     {
226         if (config.mDp)
227         {
228             found = true;
229             break;
230         }
231     }
232 
233     if (!found)
234     {
235         VerifyOrExit(HasDomainPrefix());
236 
237         // Domain Prefix does not exist any more.
238         mDomainPrefix.Clear();
239         event = kDomainPrefixRemoved;
240     }
241     else if (config.GetPrefix() == mDomainPrefix)
242     {
243         event = kDomainPrefixUnchanged;
244     }
245     else
246     {
247         event         = HasDomainPrefix() ? kDomainPrefixRefreshed : kDomainPrefixAdded;
248         mDomainPrefix = config.GetPrefix();
249     }
250 
251     LogInfo("%s domain Prefix: %s", DomainPrefixEventToString(event), mDomainPrefix.ToString().AsCString());
252 
253 #if OPENTHREAD_FTD && OPENTHREAD_CONFIG_BACKBONE_ROUTER_ENABLE
254     Get<Local>().HandleDomainPrefixUpdate(event);
255 #if OPENTHREAD_CONFIG_BACKBONE_ROUTER_DUA_NDPROXYING_ENABLE
256     Get<NdProxyTable>().HandleDomainPrefixUpdate(event);
257 #endif
258 #endif
259 
260 #if OPENTHREAD_CONFIG_DUA_ENABLE || (OPENTHREAD_FTD && OPENTHREAD_CONFIG_TMF_PROXY_DUA_ENABLE)
261     Get<DuaManager>().HandleDomainPrefixUpdate(event);
262 #else
263     OT_UNUSED_VARIABLE(event);
264 #endif
265 
266 exit:
267     return;
268 }
269 
IsDomainUnicast(const Ip6::Address & aAddress) const270 bool Leader::IsDomainUnicast(const Ip6::Address &aAddress) const
271 {
272     return HasDomainPrefix() && aAddress.MatchesPrefix(mDomainPrefix);
273 }
274 
275 } // namespace BackboneRouter
276 } // namespace ot
277 
278 #endif // (OPENTHREAD_CONFIG_THREAD_VERSION >= OT_THREAD_VERSION_1_2)
279