diff --git a/src/init.cpp b/src/init.cpp index 584b148affd..a1c026f8068 100644 --- a/src/init.cpp +++ b/src/init.cpp @@ -1698,29 +1698,17 @@ bool AppInitMain(const util::Ref& context, NodeContext& node, interfaces::BlockA break; } - bool failed_rewind{false}; - // Can't hold cs_main while calling RewindBlockIndex, so retrieve the relevant - // chainstates beforehand. - for (CChainState* chainstate : WITH_LOCK(::cs_main, return chainman.GetAll())) { - if (!fReset) { - // Note that RewindBlockIndex MUST run even if we're about to -reindex-chainstate. - // It both disconnects blocks based on the chainstate, and drops block data in - // BlockIndex() based on lack of available witness data. - uiInterface.InitMessage(_("Rewinding blocks...").translated); - if (!chainstate->RewindBlockIndex(chainparams)) { - strLoadError = _( - "Unable to rewind the database to a pre-fork state. " - "You will need to redownload the blockchain"); - failed_rewind = true; - break; // out of the per-chainstate loop - } + if (!fReset) { + LOCK(cs_main); + auto chainstates{chainman.GetAll()}; + if (std::any_of(chainstates.begin(), chainstates.end(), + [&chainparams](const CChainState* cs) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { return cs->NeedsRedownload(chainparams); })) { + strLoadError = strprintf(_("Witness data for blocks after height %d requires validation. Please restart with -reindex."), + chainparams.GetConsensus().SegwitHeight); + break; } } - if (failed_rewind) { - break; // out of the chainstate activation do-while - } - bool failed_verification = false; try { diff --git a/src/validation.cpp b/src/validation.cpp index 0c3aeced933..fdc7ef8845a 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -4431,143 +4431,23 @@ bool CChainState::ReplayBlocks(const CChainParams& params) return true; } -//! Helper for CChainState::RewindBlockIndex -void CChainState::EraseBlockData(CBlockIndex* index) +bool CChainState::NeedsRedownload(const CChainParams& params) const { AssertLockHeld(cs_main); - assert(!m_chain.Contains(index)); // Make sure this block isn't active - // Reduce validity - index->nStatus = std::min(index->nStatus & BLOCK_VALID_MASK, BLOCK_VALID_TREE) | (index->nStatus & ~BLOCK_VALID_MASK); - // Remove have-data flags. - index->nStatus &= ~(BLOCK_HAVE_DATA | BLOCK_HAVE_UNDO); - // Remove storage location. - index->nFile = 0; - index->nDataPos = 0; - index->nUndoPos = 0; - // Remove various other things - index->nTx = 0; - index->nChainTx = 0; - index->nSequenceId = 0; - // Make sure it gets written. - setDirtyBlockIndex.insert(index); - // Update indexes - setBlockIndexCandidates.erase(index); - auto ret = m_blockman.m_blocks_unlinked.equal_range(index->pprev); - while (ret.first != ret.second) { - if (ret.first->second == index) { - m_blockman.m_blocks_unlinked.erase(ret.first++); - } else { - ++ret.first; - } - } - // Mark parent as eligible for main chain again - if (index->pprev && index->pprev->IsValid(BLOCK_VALID_TRANSACTIONS) && index->pprev->HaveTxsDownloaded()) { - setBlockIndexCandidates.insert(index->pprev); - } -} - -bool CChainState::RewindBlockIndex(const CChainParams& params) -{ - // Note that during -reindex-chainstate we are called with an empty m_chain! - - // First erase all post-segwit blocks without witness not in the main chain, - // as this can we done without costly DisconnectTip calls. Active - // blocks will be dealt with below (releasing cs_main in between). - { - LOCK(cs_main); - for (const auto& entry : m_blockman.m_block_index) { - if (IsWitnessEnabled(entry.second->pprev, params.GetConsensus()) && !(entry.second->nStatus & BLOCK_OPT_WITNESS) && !m_chain.Contains(entry.second)) { - EraseBlockData(entry.second); - } + // At and above params.SegwitHeight, segwit consensus rules must be validated + CBlockIndex* block{m_chain.Tip()}; + const int segwit_height{params.GetConsensus().SegwitHeight}; + + while (block != nullptr && block->nHeight >= segwit_height) { + if (!(block->nStatus & BLOCK_OPT_WITNESS)) { + // block is insufficiently validated for a segwit client + return true; } + block = block->pprev; } - // Find what height we need to reorganize to. - CBlockIndex *tip; - int nHeight = 1; - { - LOCK(cs_main); - while (nHeight <= m_chain.Height()) { - // Although SCRIPT_VERIFY_WITNESS is now generally enforced on all - // blocks in ConnectBlock, we don't need to go back and - // re-download/re-verify blocks from before segwit actually activated. - if (IsWitnessEnabled(m_chain[nHeight - 1], params.GetConsensus()) && !(m_chain[nHeight]->nStatus & BLOCK_OPT_WITNESS)) { - break; - } - nHeight++; - } - - tip = m_chain.Tip(); - } - // nHeight is now the height of the first insufficiently-validated block, or tipheight + 1 - - BlockValidationState state; - // Loop until the tip is below nHeight, or we reach a pruned block. - while (!ShutdownRequested()) { - { - LOCK(cs_main); - LOCK(m_mempool.cs); - // Make sure nothing changed from under us (this won't happen because RewindBlockIndex runs before importing/network are active) - assert(tip == m_chain.Tip()); - if (tip == nullptr || tip->nHeight < nHeight) break; - if (fPruneMode && !(tip->nStatus & BLOCK_HAVE_DATA)) { - // If pruning, don't try rewinding past the HAVE_DATA point; - // since older blocks can't be served anyway, there's - // no need to walk further, and trying to DisconnectTip() - // will fail (and require a needless reindex/redownload - // of the blockchain). - break; - } - - // Disconnect block - if (!DisconnectTip(state, params, nullptr)) { - return error("RewindBlockIndex: unable to disconnect block at height %i (%s)", tip->nHeight, state.ToString()); - } - - // Reduce validity flag and have-data flags. - // We do this after actual disconnecting, otherwise we'll end up writing the lack of data - // to disk before writing the chainstate, resulting in a failure to continue if interrupted. - // Note: If we encounter an insufficiently validated block that - // is on m_chain, it must be because we are a pruning node, and - // this block or some successor doesn't HAVE_DATA, so we were unable to - // rewind all the way. Blocks remaining on m_chain at this point - // must not have their validity reduced. - EraseBlockData(tip); - - tip = tip->pprev; - } - // Make sure the queue of validation callbacks doesn't grow unboundedly. - LimitValidationInterfaceQueue(); - - // Occasionally flush state to disk. - if (!FlushStateToDisk(params, state, FlushStateMode::PERIODIC)) { - LogPrintf("RewindBlockIndex: unable to flush state to disk (%s)\n", state.ToString()); - return false; - } - } - - { - LOCK(cs_main); - if (m_chain.Tip() != nullptr) { - // We can't prune block index candidates based on our tip if we have - // no tip due to m_chain being empty! - PruneBlockIndexCandidates(); - - CheckBlockIndex(params.GetConsensus()); - - // FlushStateToDisk can possibly read ::ChainActive(). Be conservative - // and skip it here, we're about to -reindex-chainstate anyway, so - // it'll get called a bunch real soon. - BlockValidationState state; - if (!FlushStateToDisk(params, state, FlushStateMode::ALWAYS)) { - LogPrintf("RewindBlockIndex: unable to flush state to disk (%s)\n", state.ToString()); - return false; - } - } - } - - return true; + return false; } void CChainState::UnloadBlockIndex() { diff --git a/src/validation.h b/src/validation.h index 512b3062191..3c7f593c825 100644 --- a/src/validation.h +++ b/src/validation.h @@ -722,7 +722,9 @@ public: /** Replay blocks that aren't fully applied to the database. */ bool ReplayBlocks(const CChainParams& params); - bool RewindBlockIndex(const CChainParams& params) LOCKS_EXCLUDED(cs_main); + + /** Whether the chain state needs to be redownloaded due to lack of witness data */ + [[nodiscard]] bool NeedsRedownload(const CChainParams& params) const EXCLUSIVE_LOCKS_REQUIRED(cs_main); /** Ensures we have a genesis block in the block tree, possibly writing one to disk. */ bool LoadGenesisBlock(const CChainParams& chainparams); @@ -769,9 +771,6 @@ private: bool RollforwardBlock(const CBlockIndex* pindex, CCoinsViewCache& inputs, const CChainParams& params) EXCLUSIVE_LOCKS_REQUIRED(cs_main); - //! Mark a block as not having block data - void EraseBlockData(CBlockIndex* index) EXCLUSIVE_LOCKS_REQUIRED(cs_main); - void CheckForkWarningConditions() EXCLUSIVE_LOCKS_REQUIRED(cs_main); void InvalidChainFound(CBlockIndex* pindexNew) EXCLUSIVE_LOCKS_REQUIRED(cs_main); diff --git a/test/functional/p2p_segwit.py b/test/functional/p2p_segwit.py index 54891b07e1c..14a4afc2d76 100755 --- a/test/functional/p2p_segwit.py +++ b/test/functional/p2p_segwit.py @@ -1956,22 +1956,33 @@ class SegWitTest(BitcoinTestFramework): def test_upgrade_after_activation(self): """Test the behavior of starting up a segwit-aware node after the softfork has activated.""" - self.restart_node(2, extra_args=["-segwitheight={}".format(SEGWIT_HEIGHT)]) + # All nodes are caught up and node 2 is a pre-segwit node that will soon upgrade. + for n in range(2): + assert_equal(self.nodes[n].getblockcount(), self.nodes[2].getblockcount()) + assert softfork_active(self.nodes[n], "segwit") + assert SEGWIT_HEIGHT < self.nodes[2].getblockcount() + assert 'segwit' not in self.nodes[2].getblockchaininfo()['softforks'] + + # Restarting node 2 should result in a shutdown because the blockchain consists of + # insufficiently validated blocks per segwit consensus rules. + self.stop_node(2) + with self.nodes[2].assert_debug_log(expected_msgs=[ + f"Witness data for blocks after height {SEGWIT_HEIGHT} requires validation. Please restart with -reindex."], timeout=10): + self.nodes[2].start([f"-segwitheight={SEGWIT_HEIGHT}"]) + + # As directed, the user restarts the node with -reindex + self.start_node(2, extra_args=["-reindex", f"-segwitheight={SEGWIT_HEIGHT}"]) + + # With the segwit consensus rules, the node is able to validate only up to SEGWIT_HEIGHT - 1 + assert_equal(self.nodes[2].getblockcount(), SEGWIT_HEIGHT - 1) self.connect_nodes(0, 2) # We reconnect more than 100 blocks, give it plenty of time + # sync_blocks() also verifies the best block hash is the same for all nodes self.sync_blocks(timeout=240) - # Make sure that this peer thinks segwit has activated. - assert softfork_active(self.nodes[2], 'segwit') - - # Make sure this peer's blocks match those of node0. - height = self.nodes[2].getblockcount() - while height >= 0: - block_hash = self.nodes[2].getblockhash(height) - assert_equal(block_hash, self.nodes[0].getblockhash(height)) - assert_equal(self.nodes[0].getblock(block_hash), self.nodes[2].getblock(block_hash)) - height -= 1 + # The upgraded node should now have segwit activated + assert softfork_active(self.nodes[2], "segwit") @subtest # type: ignore def test_witness_sigops(self):