lsdb: recover lost LSA seqNo from network via sync

agawande · agawande · commit 73a96d2cecbd · 2026-03-26T12:54:02.000+05:30
refs: #5386

Change-Id: I35167fa0ba4ab5821ccbb4b95e537a645de10799
diff --git a/.mailmap b/.mailmap
@@ -1,6 +1,7 @@
 A K M Mahmudul Hoque <akmhoque@gmail.com>
 <aa@cs.fiu.edu> <alexander.afanasyev@ucla.edu>
-<agawande@memphis.edu> <ashu2493@gmail.com>
+Ashlesh Gawande <git@ashlesh.me> <ashu2493@gmail.com>
+Ashlesh Gawande <git@ashlesh.me> <agawande@memphis.edu>
 Alexander Lane <awlane@memphis.edu>
 <davidepesa@gmail.com> <davide.pesavento@lip6.fr>
 <enewberry@email.arizona.edu> <enewberry@cs.arizona.edu>
diff --git a/src/communication/sync-logic-handler.cpp b/src/communication/sync-logic-handler.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2024,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -31,9 +31,8 @@ INIT_LOGGER(SyncLogicHandler);
 const std::string LSA_COMPONENT{"LSA"};
 
 SyncLogicHandler::SyncLogicHandler(ndn::Face& face, ndn::KeyChain& keyChain,
-                                   IsLsaNew isLsaNew, const SyncLogicOptions& opts)
-  : m_isLsaNew(std::move(isLsaNew))
-  , m_routerPrefix(opts.routerPrefix)
+                                   const SyncLogicOptions& opts)
+  : m_routerPrefix(opts.routerPrefix)
   , m_hyperbolicState(opts.hyperbolicState)
   , m_nameLsaUserPrefix(makeLsaUserPrefix(opts.userPrefix, Lsa::Type::NAME))
   , m_adjLsaUserPrefix(makeLsaUserPrefix(opts.userPrefix, Lsa::Type::ADJACENCY))
@@ -69,42 +68,7 @@ SyncLogicHandler::processUpdate(const ndn::Name& updateName, uint64_t highSeq, u
   ndn::Name originRouter = networkName;
   originRouter.append(routerName);
 
-  processUpdateFromSync(originRouter, updateName, highSeq, incomingFaceId);
-}
-
-void
-SyncLogicHandler::processUpdateFromSync(const ndn::Name& originRouter,
-                                        const ndn::Name& updateName, uint64_t seqNo,
-                                        uint64_t incomingFaceId)
-{
-  NLSR_LOG_DEBUG("Origin Router of update: " << originRouter);
-
-  if (originRouter == m_routerPrefix) {
-    // A router should not try to fetch its own LSA
-    return;
-  }
-
-  auto lsaType = boost::lexical_cast<Lsa::Type>(updateName.get(-1).toUri());
-  NLSR_LOG_DEBUG("Received sync update with higher " << lsaType <<
-                  " sequence number than entry in LSDB");
-
-  if (m_isLsaNew(originRouter, lsaType, seqNo, incomingFaceId)) {
-    if (lsaType == Lsa::Type::ADJACENCY && seqNo != 0 &&
-        m_hyperbolicState == HYPERBOLIC_STATE_ON) {
-      NLSR_LOG_ERROR("Got an update for adjacency LSA when hyperbolic routing "
-                      "is enabled. Not going to fetch.");
-      return;
-    }
-
-    if (lsaType == Lsa::Type::COORDINATE && seqNo != 0 &&
-        m_hyperbolicState == HYPERBOLIC_STATE_OFF) {
-      NLSR_LOG_ERROR("Got an update for coordinate LSA when link-state "
-                      "is enabled. Not going to fetch.");
-      return;
-    }
-
-    onNewLsa(updateName, seqNo, originRouter, incomingFaceId);
-  }
+  onSyncUpdate(updateName, highSeq, originRouter, incomingFaceId);
 }
 
 void
diff --git a/src/communication/sync-logic-handler.hpp b/src/communication/sync-logic-handler.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2024,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -62,12 +62,8 @@ class SyncLogicHandler
     using std::runtime_error::runtime_error;
   };
 
-  using IsLsaNew = std::function<
-    bool (const ndn::Name& routerName, Lsa::Type lsaType, uint64_t seqNo, uint64_t inFace)
-  >;
-
   SyncLogicHandler(ndn::Face& face, ndn::KeyChain& keyChain,
-                   IsLsaNew isLsaNew, const SyncLogicOptions& opts);
+                   const SyncLogicOptions& opts);
 
   /*! \brief Instruct ChronoSync to publish an update.
    *
@@ -91,23 +87,10 @@ class SyncLogicHandler
   void
   processUpdate(const ndn::Name& updateName, uint64_t highSeq, uint64_t incomingFaceId);
 
-  /*! \brief Determine which kind of LSA was updated and fetch it.
-   *
-   * Checks that the received update is not from us, which can happen,
-   * and then inspects the update to determine which kind of LSA the
-   * update is for. Finally, it expresses interest for the correct LSA
-   * type.
-   * \throws SyncUpdate::Error If the sync update doesn't look like a sync LSA update.
-   */
-  void
-  processUpdateFromSync(const ndn::Name& originRouter,
-                        const ndn::Name& updateName, uint64_t seqNo, uint64_t incomingFaceId);
-
 public:
-  OnNewLsa onNewLsa;
+  OnSyncUpdate onSyncUpdate;
 
 private:
-  IsLsaNew m_isLsaNew;
   ndn::Name m_routerPrefix;
   HyperbolicState m_hyperbolicState;
 
diff --git a/src/lsdb.cpp b/src/lsdb.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2024,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -36,9 +36,6 @@ Lsdb::Lsdb(ndn::Face& face, ndn::KeyChain& keyChain, ConfParameter& confParam)
   , m_scheduler(face.getIoContext())
   , m_confParam(confParam)
   , m_sync(m_face, keyChain,
-      [this] (const auto& routerName, Lsa::Type lsaType, uint64_t seqNo, uint64_t) {
-        return isLsaNew(routerName, lsaType, seqNo);
-      },
       SyncLogicOptions{
         confParam.getSyncProtocol(),
         confParam.getSyncPrefix(),
@@ -51,12 +48,10 @@ Lsdb::Lsdb(ndn::Face& face, ndn::KeyChain& keyChain, ConfParameter& confParam)
   , m_adjLsaBuildInterval(m_confParam.getAdjLsaBuildInterval())
   , m_thisRouterPrefix(m_confParam.getRouterPrefix())
   , m_sequencingManager(m_confParam.getStateFileDir(), m_confParam.getHyperbolicState())
-  , m_onNewLsaConnection(m_sync.onNewLsa.connect(
+  , m_onSyncUpdate(m_sync.onSyncUpdate.connect(
       [this] (const ndn::Name& updateName, uint64_t sequenceNumber,
               const ndn::Name& originRouter, uint64_t incomingFaceId) {
-        ndn::Name lsaInterest{updateName};
-        lsaInterest.appendNumber(sequenceNumber);
-        expressInterest(lsaInterest, 0, incomingFaceId);
+        processUpdateFromSync(updateName, sequenceNumber, originRouter, incomingFaceId);
       }))
   , m_segmenter(keyChain, m_confParam.getSigningInfo())
   , m_segmentFifo(100)
@@ -89,6 +84,63 @@ Lsdb::~Lsdb()
   }
 }
 
+void
+Lsdb::processUpdateFromSync(const ndn::Name& updateName, uint64_t seqNo,
+                            const ndn::Name& originRouter, uint64_t incomingFaceId)
+{
+  NLSR_LOG_DEBUG("Origin Router of update: " << originRouter << " seq: " << seqNo);
+  auto lsaType = boost::lexical_cast<Lsa::Type>(updateName.get(-1).toUri());
+
+  if (originRouter == m_thisRouterPrefix) {
+    NLSR_LOG_TRACE("Received sync update for own router");
+    // Other routers might be telling us that they have higher sequence number
+    // than what we started with because of our sequence file corruption
+    // So we adapt that sequence number
+    if (isLsaNew(originRouter, lsaType, seqNo)) {
+      if (lsaType == Lsa::Type::NAME) {
+        m_sequencingManager.setNameLsaSeq(seqNo);
+        buildAndInstallOwnNameLsa();
+      }
+      if (lsaType == Lsa::Type::ADJACENCY &&
+          m_confParam.getHyperbolicState() == HYPERBOLIC_STATE_OFF) {
+        m_sequencingManager.setAdjLsaSeq(seqNo);
+        buildAndInstallOwnAdjLsa();
+      }
+      if (lsaType == Lsa::Type::COORDINATE &&
+          m_confParam.getHyperbolicState() == HYPERBOLIC_STATE_ON) {
+        m_sequencingManager.setCorLsaSeq(seqNo);
+        buildAndInstallOwnCoordinateLsa();
+      }
+    }
+    // A router should not try to fetch its own LSA
+    return;
+  }
+
+  NLSR_LOG_DEBUG("Received sync update with higher " << lsaType << " sequence number than entry in LSDB");
+
+  if (isLsaNew(originRouter, lsaType, seqNo)) {
+    if (lsaType == Lsa::Type::ADJACENCY && seqNo != 0 &&
+        m_confParam.getHyperbolicState() == HYPERBOLIC_STATE_ON) {
+      NLSR_LOG_ERROR("Got an update for adjacency LSA when hyperbolic routing "
+                      "is enabled. Not going to fetch.");
+      return;
+    }
+
+    if (lsaType == Lsa::Type::COORDINATE && seqNo != 0 &&
+        m_confParam.getHyperbolicState() == HYPERBOLIC_STATE_OFF) {
+      NLSR_LOG_ERROR("Got an update for coordinate LSA when link-state "
+                      "is enabled. Not going to fetch.");
+      return;
+    }
+
+    onNewLsa(updateName, seqNo, originRouter, incomingFaceId);
+
+    ndn::Name lsaInterest{updateName};
+    lsaInterest.appendNumber(seqNo);
+    expressInterest(lsaInterest, 0, incomingFaceId);
+  }
+}
+
 void
 Lsdb::buildAndInstallOwnNameLsa()
 {
diff --git a/src/lsdb.hpp b/src/lsdb.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2025,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -29,6 +29,7 @@
 #include "lsa/coordinate-lsa.hpp"
 #include "lsa/adj-lsa.hpp"
 #include "sequencing-manager.hpp"
+#include "signals.hpp"
 #include "statistics.hpp"
 #include "test-access-control.hpp"
 
@@ -82,6 +83,21 @@ class Lsdb
   void
   buildAndInstallOwnCoordinateLsa();
 
+  /*! \brief Determine which kind of LSA was updated and fetch it.
+   *
+   * If the received update is for our own router then the network
+   * is telling us that we are recovering from a sequence file corruption.
+   * So we use the sequence number provided in this update as a base
+   * and publish a new update.
+   *
+   * Otherwise if the update is for another router we inspect the update to determine
+   * which kind of LSA the update is for and expresses interest for the correct LSA
+   * type.
+   */
+  void
+  processUpdateFromSync(const ndn::Name& updateName, uint64_t seqNo,
+                        const ndn::Name& originRouter, uint64_t incomingFaceId);
+
 public:
   /*! \brief Schedules a build of this router's LSA. */
   void
@@ -337,6 +353,7 @@ class Lsdb
   using AfterLsdbModified = ndn::signal::Signal<Lsdb, std::shared_ptr<Lsa>, LsdbUpdate,
                                                 std::list<nlsr::PrefixInfo>, std::list<nlsr::PrefixInfo>>;
   AfterLsdbModified onLsdbModified;
+  OnLsaUpdate onNewLsa;
 
 PUBLIC_WITH_TESTS_ELSE_PRIVATE:
   ndn::Face& m_face;
@@ -357,7 +374,7 @@ class Lsdb
 
   SequencingManager m_sequencingManager;
 
-  ndn::signal::ScopedConnection m_onNewLsaConnection;
+  ndn::signal::ScopedConnection m_onSyncUpdate;
 
   std::set<std::shared_ptr<ndn::SegmentFetcher>> m_fetchers;
   ndn::Segmenter m_segmenter;
diff --git a/src/nlsr.cpp b/src/nlsr.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2025,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -47,7 +47,7 @@ Nlsr::Nlsr(ndn::Face& face, ndn::KeyChain& keyChain, ConfParameter& confParam)
   , m_namePrefixTable(confParam.getRouterPrefix(), m_fib, m_routingTable,
                       m_routingTable.afterRoutingChange, m_lsdb.onLsdbModified)
   , m_helloProtocol(m_face, keyChain, confParam, m_routingTable, m_lsdb)
-  , m_onNewLsaConnection(m_lsdb.getSync().onNewLsa.connect(
+  , m_onNewLsaConnection(m_lsdb.onNewLsa.connect(
       [this] (const ndn::Name& updateName, uint64_t sequenceNumber,
               const ndn::Name& originRouter, uint64_t incomingFaceId) {
         registerStrategyForCerts(originRouter);
diff --git a/src/signals.hpp b/src/signals.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2023,  The University of Memphis,
+ * Copyright (c) 2014-2026,  The University of Memphis,
  *                           Regents of the University of California,
  *                           Arizona Board of Regents.
  *
@@ -31,9 +31,11 @@ namespace nlsr {
 class RoutingTable;
 class RoutingTableEntry;
 class SyncLogicHandler;
+class Lsdb;
 
 using AfterRoutingChange = ndn::signal::Signal<RoutingTable, std::list<RoutingTableEntry>>;
-using OnNewLsa = ndn::signal::Signal<SyncLogicHandler, ndn::Name, uint64_t, ndn::Name, uint64_t>;
+using OnSyncUpdate = ndn::signal::Signal<SyncLogicHandler, ndn::Name, uint64_t, ndn::Name, uint64_t>;
+using OnLsaUpdate = ndn::signal::Signal<Lsdb, ndn::Name, uint64_t, ndn::Name, uint64_t>;
 
 } // namespace nlsr
 
diff --git a/tests/communication/test-seq-no-recovery.cpp b/tests/communication/test-seq-no-recovery.cpp
diff --git a/tests/communication/test-sync-logic-handler.cpp b/tests/communication/test-sync-logic-handler.cpp
diff --git a/tests/test-lsdb.cpp b/tests/test-lsdb.cpp
