1 files changed, 125 insertions, 115 deletions

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 74deb2dddc..ddeff8ba09 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -935,19 +935,19 @@ void CWallet::LoadToWallet(const CWalletTx& wtxIn)
     }
 }
 
-bool CWallet::AddToWalletIfInvolvingMe(const CTransactionRef& ptx, const CBlockIndex* pIndex, int posInBlock, bool fUpdate)
+bool CWallet::AddToWalletIfInvolvingMe(const CTransactionRef& ptx, const uint256& block_hash, int posInBlock, bool fUpdate)
 {
     const CTransaction& tx = *ptx;
     {
         AssertLockHeld(cs_wallet);
 
-        if (pIndex != nullptr) {
+        if (!block_hash.IsNull()) {
             for (const CTxIn& txin : tx.vin) {
                 std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range = mapTxSpends.equal_range(txin.prevout);
                 while (range.first != range.second) {
                     if (range.first->second != tx.GetHash()) {
-                        WalletLogPrintf("Transaction %s (in block %s) conflicts with wallet transaction %s (both spend %s:%i)\n", tx.GetHash().ToString(), pIndex->GetBlockHash().ToString(), range.first->second.ToString(), range.first->first.hash.ToString(), range.first->first.n);
-                        MarkConflicted(pIndex->GetBlockHash(), range.first->second);
+                        WalletLogPrintf("Transaction %s (in block %s) conflicts with wallet transaction %s (both spend %s:%i)\n", tx.GetHash().ToString(), block_hash.ToString(), range.first->second.ToString(), range.first->first.hash.ToString(), range.first->first.n);
+                        MarkConflicted(block_hash, range.first->second);
                     }
                     range.first++;
                 }
@@ -983,8 +983,8 @@ bool CWallet::AddToWalletIfInvolvingMe(const CTransactionRef& ptx, const CBlockI
             CWalletTx wtx(this, ptx);
 
             // Get merkle branch if transaction was found in a block
-            if (pIndex != nullptr)
-                wtx.SetMerkleBranch(pIndex, posInBlock);
+            if (!block_hash.IsNull())
+                wtx.SetMerkleBranch(block_hash, posInBlock);
 
             return AddToWallet(wtx, false);
         }
@@ -1071,11 +1071,7 @@ void CWallet::MarkConflicted(const uint256& hashBlock, const uint256& hashTx)
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
-    int conflictconfirms = 0;
-    CBlockIndex* pindex = LookupBlockIndex(hashBlock);
-    if (pindex && chainActive.Contains(pindex)) {
-        conflictconfirms = -(chainActive.Height() - pindex->nHeight + 1);
-    }
+    int conflictconfirms = -locked_chain->getBlockDepth(hashBlock);
     // If number of conflict confirms cannot be determined, this means
     // that the block is still unknown or not yet part of the main chain,
     // for example when loading the wallet during a reindex. Do nothing in that
@@ -1121,8 +1117,8 @@ void CWallet::MarkConflicted(const uint256& hashBlock, const uint256& hashTx)
     }
 }
 
-void CWallet::SyncTransaction(const CTransactionRef& ptx, const CBlockIndex *pindex, int posInBlock, bool update_tx) {
-    if (!AddToWalletIfInvolvingMe(ptx, pindex, posInBlock, update_tx))
+void CWallet::SyncTransaction(const CTransactionRef& ptx, const uint256& block_hash, int posInBlock, bool update_tx) {
+    if (!AddToWalletIfInvolvingMe(ptx, block_hash, posInBlock, update_tx))
         return; // Not one of ours
 
     // If a transaction changes 'conflicted' state, that changes the balance
@@ -1134,7 +1130,7 @@ void CWallet::SyncTransaction(const CTransactionRef& ptx, const CBlockIndex *pin
 void CWallet::TransactionAddedToMempool(const CTransactionRef& ptx) {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
-    SyncTransaction(ptx);
+    SyncTransaction(ptx, {} /* block hash */, 0 /* position in block */);
 
     auto it = mapWallet.find(ptx->GetHash());
     if (it != mapWallet.end()) {
@@ -1162,15 +1158,15 @@ void CWallet::BlockConnected(const std::shared_ptr<const CBlock>& pblock, const
     // the notification that the conflicted transaction was evicted.
 
     for (const CTransactionRef& ptx : vtxConflicted) {
-        SyncTransaction(ptx);
+        SyncTransaction(ptx, {} /* block hash */, 0 /* position in block */);
         TransactionRemovedFromMempool(ptx);
     }
     for (size_t i = 0; i < pblock->vtx.size(); i++) {
-        SyncTransaction(pblock->vtx[i], pindex, i);
+        SyncTransaction(pblock->vtx[i], pindex->GetBlockHash(), i);
         TransactionRemovedFromMempool(pblock->vtx[i]);
     }
 
-    m_last_block_processed = pindex;
+    m_last_block_processed = pindex->GetBlockHash();
 }
 
 void CWallet::BlockDisconnected(const std::shared_ptr<const CBlock>& pblock) {
@@ -1178,7 +1174,7 @@ void CWallet::BlockDisconnected(const std::shared_ptr<const CBlock>& pblock) {
     LOCK(cs_wallet);
 
     for (const CTransactionRef& ptx : pblock->vtx) {
-        SyncTransaction(ptx);
+        SyncTransaction(ptx, {} /* block hash */, 0 /* position in block */);
     }
 }
 
@@ -1195,9 +1191,8 @@ void CWallet::BlockUntilSyncedToCurrentChain() {
         // protected by cs_wallet instead of cs_main, but as long as we need
         // cs_main here anyway, it's easier to just call it cs_main-protected.
         auto locked_chain = chain().lock();
-        const CBlockIndex* initialChainTip = chainActive.Tip();
 
-        if (m_last_block_processed && m_last_block_processed->GetAncestor(initialChainTip->nHeight) == initialChainTip) {
+        if (!m_last_block_processed.IsNull() && locked_chain->isPotentialTip(m_last_block_processed)) {
             return;
         }
     }
@@ -1591,132 +1586,143 @@ int64_t CWallet::RescanFromTime(int64_t startTime, const WalletRescanReserver& r
     // Find starting block. May be null if nCreateTime is greater than the
     // highest blockchain timestamp, in which case there is nothing that needs
     // to be scanned.
-    CBlockIndex* startBlock = nullptr;
+    uint256 start_block;
     {
         auto locked_chain = chain().lock();
-        startBlock = chainActive.FindEarliestAtLeast(startTime - TIMESTAMP_WINDOW);
-        WalletLogPrintf("%s: Rescanning last %i blocks\n", __func__, startBlock ? chainActive.Height() - startBlock->nHeight + 1 : 0);
+        const Optional<int> start_height = locked_chain->findFirstBlockWithTime(startTime - TIMESTAMP_WINDOW, &start_block);
+        const Optional<int> tip_height = locked_chain->getHeight();
+        WalletLogPrintf("%s: Rescanning last %i blocks\n", __func__, tip_height && start_height ? *tip_height - *start_height + 1 : 0);
     }
 
-    if (startBlock) {
-        const CBlockIndex *failedBlock, *stop_block;
+    if (!start_block.IsNull()) {
         // TODO: this should take into account failure by ScanResult::USER_ABORT
-        if (ScanResult::FAILURE == ScanForWalletTransactions(startBlock, nullptr, reserver, failedBlock, stop_block, update)) {
-            return failedBlock->GetBlockTimeMax() + TIMESTAMP_WINDOW + 1;
+        ScanResult result = ScanForWalletTransactions(start_block, {} /* stop_block */, reserver, update);
+        if (result.status == ScanResult::FAILURE) {
+            int64_t time_max;
+            if (!chain().findBlock(result.failed_block, nullptr /* block */, nullptr /* time */, &time_max)) {
+                throw std::logic_error("ScanForWalletTransactions returned invalid block hash");
+            }
+            return time_max + TIMESTAMP_WINDOW + 1;
         }
     }
     return startTime;
 }
 
 /**
- * Scan the block chain (starting in pindexStart) for transactions
+ * Scan the block chain (starting in start_block) for transactions
  * from or to us. If fUpdate is true, found transactions that already
  * exist in the wallet will be updated.
  *
- * @param[in] pindexStop if not a nullptr, the scan will stop at this block-index
- * @param[out] failed_block if FAILURE is returned, the most recent block
- *     that could not be scanned, otherwise nullptr
- * @param[out] stop_block the most recent block that could be scanned,
- *     otherwise nullptr if no block could be scanned
+ * @param[in] start_block if not null, the scan will start at this block instead
+ *            of the genesis block
+ * @param[in] stop_block if not null, the scan will stop at this block instead
+ *            of the chain tip
  *
  * @return ScanResult indicating success or failure of the scan. SUCCESS if
  * scan was successful. FAILURE if a complete rescan was not possible (due to
  * pruning or corruption). USER_ABORT if the rescan was aborted before it
  * could complete.
  *
- * @pre Caller needs to make sure pindexStop (and the optional pindexStart) are on
+ * @pre Caller needs to make sure start_block (and the optional stop_block) are on
  * the main chain after to the addition of any new keys you want to detect
  * transactions for.
  */
-CWallet::ScanResult CWallet::ScanForWalletTransactions(const CBlockIndex* const pindexStart, const CBlockIndex* const pindexStop, const WalletRescanReserver& reserver, const CBlockIndex*& failed_block, const CBlockIndex*& stop_block, bool fUpdate)
+CWallet::ScanResult CWallet::ScanForWalletTransactions(const uint256& start_block, const uint256& stop_block, const WalletRescanReserver& reserver, bool fUpdate)
 {
     int64_t nNow = GetTime();
-    const CChainParams& chainParams = Params();
 
     assert(reserver.isReserved());
-    if (pindexStop) {
-        assert(pindexStop->nHeight >= pindexStart->nHeight);
-    }
 
-    const CBlockIndex* pindex = pindexStart;
-    failed_block = nullptr;
-    stop_block = nullptr;
+    uint256 block_hash = start_block;
+    ScanResult result;
 
-    if (pindex) WalletLogPrintf("Rescan started from block %d...\n", pindex->nHeight);
+    WalletLogPrintf("Rescan started from block %s...\n", start_block.ToString());
 
     {
         fAbortRescan = false;
         ShowProgress(strprintf("%s " + _("Rescanning..."), GetDisplayName()), 0); // show rescan progress in GUI as dialog or on splashscreen, if -rescan on startup
-        CBlockIndex* tip = nullptr;
+        uint256 tip_hash;
+        Optional<int> block_height;
         double progress_begin;
         double progress_end;
         {
             auto locked_chain = chain().lock();
-            progress_begin = GuessVerificationProgress(chainParams.TxData(), pindex);
-            if (pindexStop == nullptr) {
-                tip = chainActive.Tip();
-                progress_end = GuessVerificationProgress(chainParams.TxData(), tip);
-            } else {
-                progress_end = GuessVerificationProgress(chainParams.TxData(), pindexStop);
+            if (Optional<int> tip_height = locked_chain->getHeight()) {
+                tip_hash = locked_chain->getBlockHash(*tip_height);
             }
+            block_height = locked_chain->getBlockHeight(block_hash);
+            progress_begin = chain().guessVerificationProgress(block_hash);
+            progress_end = chain().guessVerificationProgress(stop_block.IsNull() ? tip_hash : stop_block);
         }
         double progress_current = progress_begin;
-        while (pindex && !fAbortRescan && !ShutdownRequested()) {
-            if (pindex->nHeight % 100 == 0 && progress_end - progress_begin > 0.0) {
+        while (block_height && !fAbortRescan && !ShutdownRequested()) {
+            if (*block_height % 100 == 0 && progress_end - progress_begin > 0.0) {
                 ShowProgress(strprintf("%s " + _("Rescanning..."), GetDisplayName()), std::max(1, std::min(99, (int)((progress_current - progress_begin) / (progress_end - progress_begin) * 100))));
             }
             if (GetTime() >= nNow + 60) {
                 nNow = GetTime();
-                WalletLogPrintf("Still rescanning. At block %d. Progress=%f\n", pindex->nHeight, progress_current);
+                WalletLogPrintf("Still rescanning. At block %d. Progress=%f\n", *block_height, progress_current);
             }
 
             CBlock block;
-            if (ReadBlockFromDisk(block, pindex, Params().GetConsensus())) {
+            if (chain().findBlock(block_hash, &block) && !block.IsNull()) {
                 auto locked_chain = chain().lock();
                 LOCK(cs_wallet);
-                if (pindex && !chainActive.Contains(pindex)) {
+                if (!locked_chain->getBlockHeight(block_hash)) {
                     // Abort scan if current block is no longer active, to prevent
                     // marking transactions as coming from the wrong block.
-                    failed_block = pindex;
+                    // TODO: This should return success instead of failure, see
+                    // https://github.com/bitcoin/bitcoin/pull/14711#issuecomment-458342518
+                    result.failed_block = block_hash;
+                    result.status = ScanResult::FAILURE;
                     break;
                 }
                 for (size_t posInBlock = 0; posInBlock < block.vtx.size(); ++posInBlock) {
-                    SyncTransaction(block.vtx[posInBlock], pindex, posInBlock, fUpdate);
+                    SyncTransaction(block.vtx[posInBlock], block_hash, posInBlock, fUpdate);
                 }
                 // scan succeeded, record block as most recent successfully scanned
-                stop_block = pindex;
+                result.stop_block = block_hash;
+                result.stop_height = *block_height;
             } else {
                 // could not scan block, keep scanning but record this block as the most recent failure
-                failed_block = pindex;
+                result.failed_block = block_hash;
+                result.status = ScanResult::FAILURE;
             }
-            if (pindex == pindexStop) {
+            if (block_hash == stop_block) {
                 break;
             }
             {
                 auto locked_chain = chain().lock();
-                pindex = chainActive.Next(pindex);
-                progress_current = GuessVerificationProgress(chainParams.TxData(), pindex);
-                if (pindexStop == nullptr && tip != chainActive.Tip()) {
-                    tip = chainActive.Tip();
+                Optional<int> tip_height = locked_chain->getHeight();
+                if (!tip_height || *tip_height <= block_height || !locked_chain->getBlockHeight(block_hash)) {
+                    // break successfully when rescan has reached the tip, or
+                    // previous block is no longer on the chain due to a reorg
+                    break;
+                }
+
+                // increment block and verification progress
+                block_hash = locked_chain->getBlockHash(++*block_height);
+                progress_current = chain().guessVerificationProgress(block_hash);
+
+                // handle updated tip hash
+                const uint256 prev_tip_hash = tip_hash;
+                tip_hash = locked_chain->getBlockHash(*tip_height);
+                if (stop_block.IsNull() && prev_tip_hash != tip_hash) {
                     // in case the tip has changed, update progress max
-                    progress_end = GuessVerificationProgress(chainParams.TxData(), tip);
+                    progress_end = chain().guessVerificationProgress(tip_hash);
                 }
             }
         }
         ShowProgress(strprintf("%s " + _("Rescanning..."), GetDisplayName()), 100); // hide progress dialog in GUI
-        if (pindex && fAbortRescan) {
-            WalletLogPrintf("Rescan aborted at block %d. Progress=%f\n", pindex->nHeight, progress_current);
-            return ScanResult::USER_ABORT;
-        } else if (pindex && ShutdownRequested()) {
-            WalletLogPrintf("Rescan interrupted by shutdown request at block %d. Progress=%f\n", pindex->nHeight, progress_current);
-            return ScanResult::USER_ABORT;
+        if (block_height && fAbortRescan) {
+            WalletLogPrintf("Rescan aborted at block %d. Progress=%f\n", block_height.value_or(0), progress_current);
+            result.status = ScanResult::USER_ABORT;
+        } else if (block_height && ShutdownRequested()) {
+            WalletLogPrintf("Rescan interrupted by shutdown request at block %d. Progress=%f\n", block_height.value_or(0), progress_current);
+            result.status = ScanResult::USER_ABORT;
         }
     }
-    if (failed_block) {
-        return ScanResult::FAILURE;
-    } else {
-        return ScanResult::SUCCESS;
-    }
+    return result;
 }
 
 void CWallet::ReacceptWalletTransactions()
@@ -2573,6 +2579,7 @@ static bool IsCurrentForAntiFeeSniping(interfaces::Chain::Lock& locked_chain)
  */
 static uint32_t GetLocktimeForNewTransaction(interfaces::Chain::Lock& locked_chain)
 {
+    uint32_t const height = locked_chain.getHeight().value_or(-1);
     uint32_t locktime;
     // Discourage fee sniping.
     //
@@ -2595,7 +2602,7 @@ static uint32_t GetLocktimeForNewTransaction(interfaces::Chain::Lock& locked_cha
     // now we ensure code won't be written that makes assumptions about
     // nLockTime that preclude a fix later.
     if (IsCurrentForAntiFeeSniping(locked_chain)) {
-        locktime = chainActive.Height();
+        locktime = height;
 
         // Secondly occasionally randomly pick a nLockTime even further back, so
         // that transactions that are delayed after signing for whatever reason,
@@ -2609,7 +2616,7 @@ static uint32_t GetLocktimeForNewTransaction(interfaces::Chain::Lock& locked_cha
         // unique "nLockTime fingerprint", set nLockTime to a constant.
         locktime = 0;
     }
-    assert(locktime <= (unsigned int)chainActive.Height());
+    assert(locktime <= height);
     assert(locktime < LOCKTIME_THRESHOLD);
     return locktime;
 }
@@ -3718,11 +3725,12 @@ void CWallet::GetKeyBirthTimes(interfaces::Chain::Lock& locked_chain, std::map<C
     }
 
     // map in which we'll infer heights of other keys
-    CBlockIndex *pindexMax = chainActive[std::max(0, chainActive.Height() - 144)]; // the tip can be reorganized; use a 144-block safety margin
-    std::map<CKeyID, CBlockIndex*> mapKeyFirstBlock;
+    const Optional<int> tip_height = locked_chain.getHeight();
+    const int max_height = tip_height && *tip_height > 144 ? *tip_height - 144 : 0; // the tip can be reorganized; use a 144-block safety margin
+    std::map<CKeyID, int> mapKeyFirstBlock;
     for (const CKeyID &keyid : GetKeys()) {
         if (mapKeyBirth.count(keyid) == 0)
-            mapKeyFirstBlock[keyid] = pindexMax;
+            mapKeyFirstBlock[keyid] = max_height;
     }
 
     // if there are no such keys, we're done
@@ -3733,17 +3741,15 @@ void CWallet::GetKeyBirthTimes(interfaces::Chain::Lock& locked_chain, std::map<C
     for (const auto& entry : mapWallet) {
         // iterate over all wallet transactions...
         const CWalletTx &wtx = entry.second;
-        CBlockIndex* pindex = LookupBlockIndex(wtx.hashBlock);
-        if (pindex && chainActive.Contains(pindex)) {
+        if (Optional<int> height = locked_chain.getBlockHeight(wtx.hashBlock)) {
             // ... which are already in a block
-            int nHeight = pindex->nHeight;
             for (const CTxOut &txout : wtx.tx->vout) {
                 // iterate over all their outputs
                 for (const auto &keyid : GetAffectedKeys(txout.scriptPubKey, *this)) {
                     // ... and all their affected keys
-                    std::map<CKeyID, CBlockIndex*>::iterator rit = mapKeyFirstBlock.find(keyid);
-                    if (rit != mapKeyFirstBlock.end() && nHeight < rit->second->nHeight)
-                        rit->second = pindex;
+                    std::map<CKeyID, int>::iterator rit = mapKeyFirstBlock.find(keyid);
+                    if (rit != mapKeyFirstBlock.end() && *height < rit->second)
+                        rit->second = *height;
                 }
             }
         }
@@ -3751,7 +3757,7 @@ void CWallet::GetKeyBirthTimes(interfaces::Chain::Lock& locked_chain, std::map<C
 
     // Extract block timestamps for those keys
     for (const auto& entry : mapKeyFirstBlock)
-        mapKeyBirth[entry.first] = entry.second->GetBlockTime() - TIMESTAMP_WINDOW; // block times can be 2h off
+        mapKeyBirth[entry.first] = locked_chain.getBlockTime(entry.second) - TIMESTAMP_WINDOW; // block times can be 2h off
 }
 
 /**
@@ -3779,7 +3785,8 @@ unsigned int CWallet::ComputeTimeSmart(const CWalletTx& wtx) const
 {
     unsigned int nTimeSmart = wtx.nTimeReceived;
     if (!wtx.hashUnset()) {
-        if (const CBlockIndex* pindex = LookupBlockIndex(wtx.hashBlock)) {
+        int64_t blocktime;
+        if (chain().findBlock(wtx.hashBlock, nullptr /* block */, &blocktime)) {
             int64_t latestNow = wtx.nTimeReceived;
             int64_t latestEntry = 0;
 
@@ -3805,7 +3812,6 @@ unsigned int CWallet::ComputeTimeSmart(const CWalletTx& wtx) const
                 }
             }
 
-            int64_t blocktime = pindex->GetBlockTime();
             nTimeSmart = std::max(latestEntry, std::min(blocktime, latestNow));
         } else {
             WalletLogPrintf("%s: found %s in block %s not in index\n", __func__, wtx.GetHash().ToString(), wtx.hashBlock.ToString());
@@ -4067,7 +4073,7 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
         }
 
         auto locked_chain = chain.assumeLocked();  // Temporary. Removed in upcoming lock cleanup
-        walletInstance->ChainStateFlushed(chainActive.GetLocator());
+        walletInstance->ChainStateFlushed(locked_chain->getLocator());
     } else if (wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS) {
         // Make it impossible to disable private keys after creation
         InitError(strprintf(_("Error loading %s: Private keys can only be disabled during creation"), walletFile));
@@ -4154,58 +4160,67 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
     // Try to top up keypool. No-op if the wallet is locked.
     walletInstance->TopUpKeyPool();
 
-    LockAnnotation lock(::cs_main); // Temporary, for FindForkInGlobalIndex below. Removed in upcoming commit.
     auto locked_chain = chain.lock();
     LOCK(walletInstance->cs_wallet);
 
-    CBlockIndex *pindexRescan = chainActive.Genesis();
+    int rescan_height = 0;
     if (!gArgs.GetBoolArg("-rescan", false))
     {
         WalletBatch batch(*walletInstance->database);
         CBlockLocator locator;
-        if (batch.ReadBestBlock(locator))
-            pindexRescan = FindForkInGlobalIndex(chainActive, locator);
+        if (batch.ReadBestBlock(locator)) {
+            if (const Optional<int> fork_height = locked_chain->findLocatorFork(locator)) {
+                rescan_height = *fork_height;
+            }
+        }
     }
 
-    walletInstance->m_last_block_processed = chainActive.Tip();
+    const Optional<int> tip_height = locked_chain->getHeight();
+    if (tip_height) {
+        walletInstance->m_last_block_processed = locked_chain->getBlockHash(*tip_height);
+    } else {
+        walletInstance->m_last_block_processed.SetNull();
+    }
 
-    if (chainActive.Tip() && chainActive.Tip() != pindexRescan)
+    if (tip_height && *tip_height != rescan_height)
     {
         //We can't rescan beyond non-pruned blocks, stop and throw an error
         //this might happen if a user uses an old wallet within a pruned node
         // or if he ran -disablewallet for a longer time, then decided to re-enable
         if (fPruneMode)
         {
-            CBlockIndex *block = chainActive.Tip();
-            while (block && block->pprev && (block->pprev->nStatus & BLOCK_HAVE_DATA) && block->pprev->nTx > 0 && pindexRescan != block)
-                block = block->pprev;
+            int block_height = *tip_height;
+            while (block_height > 0 && locked_chain->haveBlockOnDisk(block_height - 1) && rescan_height != block_height) {
+                --block_height;
+            }
 
-            if (pindexRescan != block) {
+            if (rescan_height != block_height) {
                 InitError(_("Prune: last wallet synchronisation goes beyond pruned data. You need to -reindex (download the whole blockchain again in case of pruned node)"));
                 return nullptr;
             }
         }
 
         uiInterface.InitMessage(_("Rescanning..."));
-        walletInstance->WalletLogPrintf("Rescanning last %i blocks (from block %i)...\n", chainActive.Height() - pindexRescan->nHeight, pindexRescan->nHeight);
+        walletInstance->WalletLogPrintf("Rescanning last %i blocks (from block %i)...\n", *tip_height - rescan_height, rescan_height);
 
         // No need to read and scan block if block was created before
         // our wallet birthday (as adjusted for block time variability)
-        while (pindexRescan && walletInstance->nTimeFirstKey && (pindexRescan->GetBlockTime() < (walletInstance->nTimeFirstKey - TIMESTAMP_WINDOW))) {
-            pindexRescan = chainActive.Next(pindexRescan);
+        if (walletInstance->nTimeFirstKey) {
+            if (Optional<int> first_block = locked_chain->findFirstBlockWithTimeAndHeight(walletInstance->nTimeFirstKey - TIMESTAMP_WINDOW, rescan_height)) {
+                rescan_height = *first_block;
+            }
         }
 
         nStart = GetTimeMillis();
         {
             WalletRescanReserver reserver(walletInstance.get());
-            const CBlockIndex *stop_block, *failed_block;
-            if (!reserver.reserve() || (ScanResult::SUCCESS != walletInstance->ScanForWalletTransactions(pindexRescan, nullptr, reserver, failed_block, stop_block, true))) {
+            if (!reserver.reserve() || (ScanResult::SUCCESS != walletInstance->ScanForWalletTransactions(locked_chain->getBlockHash(rescan_height), {} /* stop block */, reserver, true /* update */).status)) {
                 InitError(_("Failed to rescan the wallet during initialization"));
                 return nullptr;
             }
         }
         walletInstance->WalletLogPrintf("Rescan completed in %15dms\n", GetTimeMillis() - nStart);
-        walletInstance->ChainStateFlushed(chainActive.GetLocator());
+        walletInstance->ChainStateFlushed(locked_chain->getLocator());
         walletInstance->database->IncrementUpdateCounter();
 
         // Restore wallet transaction metadata after -zapwallettxes=1
@@ -4282,10 +4297,10 @@ CWalletKey::CWalletKey(int64_t nExpires)
     nTimeExpires = nExpires;
 }
 
-void CMerkleTx::SetMerkleBranch(const CBlockIndex* pindex, int posInBlock)
+void CMerkleTx::SetMerkleBranch(const uint256& block_hash, int posInBlock)
 {
     // Update the tx's hashBlock
-    hashBlock = pindex->GetBlockHash();
+    hashBlock = block_hash;
 
     // set the position of the transaction in the block
     nIndex = posInBlock;
@@ -4298,12 +4313,7 @@ int CMerkleTx::GetDepthInMainChain(interfaces::Chain::Lock& locked_chain) const
 
     AssertLockHeld(cs_main);
 
-    // Find the block it claims to be in
-    CBlockIndex* pindex = LookupBlockIndex(hashBlock);
-    if (!pindex || !chainActive.Contains(pindex))
-        return 0;
-
-    return ((nIndex == -1) ? (-1) : 1) * (chainActive.Height() - pindex->nHeight + 1);
+    return locked_chain.getBlockDepth(hashBlock) * (nIndex == -1 ? -1 : 1);
 }
 
 int CMerkleTx::GetBlocksToMaturity(interfaces::Chain::Lock& locked_chain) const