// Copyright (c) 2014-2017 The Dash Core developers // Distributed under the MIT/X11 software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #include "activemasternode.h" #include "instantx.h" #include "key.h" #include "main.h" #include "masternode-sync.h" #include "masternodeman.h" #include "messagesigner.h" #include "net.h" #include "protocol.h" #include "spork.h" #include "sync.h" #include "txmempool.h" #include "util.h" #include "consensus/validation.h" #include #include extern CWallet* pwalletMain; extern CTxMemPool mempool; bool fEnableInstantSend = true; int nInstantSendDepth = DEFAULT_INSTANTSEND_DEPTH; int nCompleteTXLocks; CInstantSend instantsend; // Transaction Locks // // step 1) Some node announces intention to lock transaction inputs via "txlreg" message // step 2) Top COutPointLock::SIGNATURES_TOTAL masternodes per each spent outpoint push "txvote" message // step 3) Once there are COutPointLock::SIGNATURES_REQUIRED valid "txvote" messages per each spent outpoint // for a corresponding "txlreg" message, all outpoints from that tx are treated as locked // // CInstantSend // void CInstantSend::ProcessMessage(CNode* pfrom, std::string& strCommand, CDataStream& vRecv) { if(fLiteMode) return; // disable all Dash specific functionality if(!sporkManager.IsSporkActive(SPORK_2_INSTANTSEND_ENABLED)) return; // Ignore any InstantSend messages until masternode list is synced if(!masternodeSync.IsMasternodeListSynced()) return; // NOTE: NetMsgType::TXLOCKREQUEST is handled via ProcessMessage() in main.cpp if (strCommand == NetMsgType::TXLOCKVOTE) // InstantSend Transaction Lock Consensus Votes { if(pfrom->nVersion < MIN_INSTANTSEND_PROTO_VERSION) return; CTxLockVote vote; vRecv >> vote; LOCK2(cs_main, cs_instantsend); uint256 nVoteHash = vote.GetHash(); if(mapTxLockVotes.count(nVoteHash)) return; mapTxLockVotes.insert(std::make_pair(nVoteHash, vote)); ProcessTxLockVote(pfrom, vote); return; } } bool CInstantSend::ProcessTxLockRequest(const CTxLockRequest& txLockRequest) { LOCK2(cs_main, cs_instantsend); uint256 txHash = txLockRequest.GetHash(); // Check to see if we conflict with existing completed lock, // fail if so, there can't be 2 completed locks for the same outpoint BOOST_FOREACH(const CTxIn& txin, txLockRequest.vin) { std::map::iterator it = mapLockedOutpoints.find(txin.prevout); if(it != mapLockedOutpoints.end()) { // Conflicting with complete lock, ignore this one // (this could be the one we have but we don't want to try to lock it twice anyway) LogPrintf("CInstantSend::ProcessTxLockRequest -- WARNING: Found conflicting completed Transaction Lock, skipping current one, txid=%s, completed lock txid=%s\n", txLockRequest.GetHash().ToString(), it->second.ToString()); return false; } } // Check to see if there are votes for conflicting request, // if so - do not fail, just warn user BOOST_FOREACH(const CTxIn& txin, txLockRequest.vin) { std::map >::iterator it = mapVotedOutpoints.find(txin.prevout); if(it != mapVotedOutpoints.end()) { BOOST_FOREACH(const uint256& hash, it->second) { if(hash != txLockRequest.GetHash()) { LogPrint("instantsend", "CInstantSend::ProcessTxLockRequest -- Double spend attempt! %s\n", txin.prevout.ToStringShort()); // do not fail here, let it go and see which one will get the votes to be locked } } } } if(!CreateTxLockCandidate(txLockRequest)) { // smth is not right LogPrintf("CInstantSend::ProcessTxLockRequest -- CreateTxLockCandidate failed, txid=%s\n", txHash.ToString()); return false; } LogPrintf("CInstantSend::ProcessTxLockRequest -- accepted, txid=%s\n", txHash.ToString()); std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); CTxLockCandidate& txLockCandidate = itLockCandidate->second; Vote(txLockCandidate); ProcessOrphanTxLockVotes(); // Masternodes will sometimes propagate votes before the transaction is known to the client. // If this just happened - lock inputs, resolve conflicting locks, update transaction status // forcing external script notification. TryToFinalizeLockCandidate(txLockCandidate); return true; } bool CInstantSend::CreateTxLockCandidate(const CTxLockRequest& txLockRequest) { // Normally we should require all outpoints to be unspent, but in case we are reprocessing // because of a lot of legit orphan votes we should also check already spent outpoints. uint256 txHash = txLockRequest.GetHash(); if(!txLockRequest.IsValid(!IsEnoughOrphanVotesForTx(txLockRequest))) return false; LOCK(cs_instantsend); std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); if(itLockCandidate == mapTxLockCandidates.end()) { LogPrintf("CInstantSend::CreateTxLockCandidate -- new, txid=%s\n", txHash.ToString()); CTxLockCandidate txLockCandidate(txLockRequest); // all inputs should already be checked by txLockRequest.IsValid() above, just use them now BOOST_REVERSE_FOREACH(const CTxIn& txin, txLockRequest.vin) { txLockCandidate.AddOutPointLock(txin.prevout); } mapTxLockCandidates.insert(std::make_pair(txHash, txLockCandidate)); } else { LogPrint("instantsend", "CInstantSend::CreateTxLockCandidate -- seen, txid=%s\n", txHash.ToString()); } return true; } void CInstantSend::Vote(CTxLockCandidate& txLockCandidate) { if(!fMasterNode) return; LOCK2(cs_main, cs_instantsend); uint256 txHash = txLockCandidate.GetHash(); // check if we need to vote on this candidate's outpoints, // it's possible that we need to vote for several of them std::map::iterator itOutpointLock = txLockCandidate.mapOutPointLocks.begin(); while(itOutpointLock != txLockCandidate.mapOutPointLocks.end()) { int nPrevoutHeight = GetUTXOHeight(itOutpointLock->first); if(nPrevoutHeight == -1) { LogPrint("instantsend", "CInstantSend::Vote -- Failed to find UTXO %s\n", itOutpointLock->first.ToStringShort()); return; } int nLockInputHeight = nPrevoutHeight + 4; int n = mnodeman.GetMasternodeRank(activeMasternode.vin, nLockInputHeight, MIN_INSTANTSEND_PROTO_VERSION); if(n == -1) { LogPrint("instantsend", "CInstantSend::Vote -- Can't calculate rank for masternode %s\n", activeMasternode.vin.prevout.ToStringShort()); ++itOutpointLock; continue; } int nSignaturesTotal = COutPointLock::SIGNATURES_TOTAL; if(n > nSignaturesTotal) { LogPrint("instantsend", "CInstantSend::Vote -- Masternode not in the top %d (%d)\n", nSignaturesTotal, n); ++itOutpointLock; continue; } LogPrint("instantsend", "CInstantSend::Vote -- In the top %d (%d)\n", nSignaturesTotal, n); std::map >::iterator itVoted = mapVotedOutpoints.find(itOutpointLock->first); // Check to see if we already voted for this outpoint, // refuse to vote twice or to include the same outpoint in another tx bool fAlreadyVoted = false; if(itVoted != mapVotedOutpoints.end()) { BOOST_FOREACH(const uint256& hash, itVoted->second) { std::map::iterator it2 = mapTxLockCandidates.find(hash); if(it2->second.HasMasternodeVoted(itOutpointLock->first, activeMasternode.vin.prevout)) { // we already voted for this outpoint to be included either in the same tx or in a competing one, // skip it anyway fAlreadyVoted = true; LogPrintf("CInstantSend::Vote -- WARNING: We already voted for this outpoint, skipping: txHash=%s, outpoint=%s\n", txHash.ToString(), itOutpointLock->first.ToStringShort()); break; } } } if(fAlreadyVoted) { ++itOutpointLock; continue; // skip to the next outpoint } // we haven't voted for this outpoint yet, let's try to do this now CTxLockVote vote(txHash, itOutpointLock->first, activeMasternode.vin.prevout); if(!vote.Sign()) { LogPrintf("CInstantSend::Vote -- Failed to sign consensus vote\n"); return; } if(!vote.CheckSignature()) { LogPrintf("CInstantSend::Vote -- Signature invalid\n"); return; } // vote constructed sucessfully, let's store and relay it uint256 nVoteHash = vote.GetHash(); mapTxLockVotes.insert(std::make_pair(nVoteHash, vote)); if(itOutpointLock->second.AddVote(vote)) { LogPrintf("CInstantSend::Vote -- Vote created successfully, relaying: txHash=%s, outpoint=%s, vote=%s\n", txHash.ToString(), itOutpointLock->first.ToStringShort(), nVoteHash.ToString()); if(itVoted == mapVotedOutpoints.end()) { std::set setHashes; setHashes.insert(txHash); mapVotedOutpoints.insert(std::make_pair(itOutpointLock->first, setHashes)); } else { mapVotedOutpoints[itOutpointLock->first].insert(txHash); if(mapVotedOutpoints[itOutpointLock->first].size() > 1) { // it's ok to continue, just warn user LogPrintf("CInstantSend::Vote -- WARNING: Vote conflicts with some existing votes: txHash=%s, outpoint=%s, vote=%s\n", txHash.ToString(), itOutpointLock->first.ToStringShort(), nVoteHash.ToString()); } } vote.Relay(); } ++itOutpointLock; } } //received a consensus vote bool CInstantSend::ProcessTxLockVote(CNode* pfrom, CTxLockVote& vote) { LOCK2(cs_main, cs_instantsend); uint256 txHash = vote.GetTxHash(); if(!vote.IsValid(pfrom)) { // could be because of missing MN LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Vote is invalid, txid=%s\n", txHash.ToString()); return false; } // Masternodes will sometimes propagate votes before the transaction is known to the client, // will actually process only after the lock request itself has arrived std::map::iterator it = mapTxLockCandidates.find(txHash); if(it == mapTxLockCandidates.end()) { if(!mapTxLockVotesOrphan.count(vote.GetHash())) { mapTxLockVotesOrphan[vote.GetHash()] = vote; LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Orphan vote: txid=%s masternode=%s new\n", txHash.ToString(), vote.GetMasternodeOutpoint().ToStringShort()); bool fReprocess = true; std::map::iterator itLockRequest = mapLockRequestAccepted.find(txHash); if(itLockRequest == mapLockRequestAccepted.end()) { itLockRequest = mapLockRequestRejected.find(txHash); if(itLockRequest == mapLockRequestRejected.end()) { // still too early, wait for tx lock request fReprocess = false; } } if(fReprocess && IsEnoughOrphanVotesForTx(itLockRequest->second)) { // We have enough votes for corresponding lock to complete, // tx lock request should already be received at this stage. LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Found enough orphan votes, reprocessing Transaction Lock Request: txid=%s\n", txHash.ToString()); ProcessTxLockRequest(itLockRequest->second); return true; } } else { LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Orphan vote: txid=%s masternode=%s seen\n", txHash.ToString(), vote.GetMasternodeOutpoint().ToStringShort()); } // This tracks those messages and allows only the same rate as of the rest of the network // TODO: make sure this works good enough for multi-quorum int nMasternodeOrphanExpireTime = GetTime() + 60*10; // keep time data for 10 minutes if(!mapMasternodeOrphanVotes.count(vote.GetMasternodeOutpoint())) { mapMasternodeOrphanVotes[vote.GetMasternodeOutpoint()] = nMasternodeOrphanExpireTime; } else { int64_t nPrevOrphanVote = mapMasternodeOrphanVotes[vote.GetMasternodeOutpoint()]; if(nPrevOrphanVote > GetTime() && nPrevOrphanVote > GetAverageMasternodeOrphanVoteTime()) { LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- masternode is spamming orphan Transaction Lock Votes: txid=%s masternode=%s\n", txHash.ToString(), vote.GetMasternodeOutpoint().ToStringShort()); // Misbehaving(pfrom->id, 1); return false; } // not spamming, refresh mapMasternodeOrphanVotes[vote.GetMasternodeOutpoint()] = nMasternodeOrphanExpireTime; } return true; } LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Transaction Lock Vote, txid=%s\n", txHash.ToString()); std::map >::iterator it1 = mapVotedOutpoints.find(vote.GetOutpoint()); if(it1 != mapVotedOutpoints.end()) { BOOST_FOREACH(const uint256& hash, it1->second) { if(hash != txHash) { // same outpoint was already voted to be locked by another tx lock request, // find out if the same mn voted on this outpoint before std::map::iterator it2 = mapTxLockCandidates.find(hash); if(it2->second.HasMasternodeVoted(vote.GetOutpoint(), vote.GetMasternodeOutpoint())) { // yes, it did, refuse to accept a vote to include the same outpoint in another tx // from the same masternode. // TODO: apply pose ban score to this masternode? // NOTE: if we decide to apply pose ban score here, this vote must be relayed further // to let all other nodes know about this node's misbehaviour and let them apply // pose ban score too. LogPrintf("CInstantSend::ProcessTxLockVote -- masternode sent conflicting votes! %s\n", vote.GetMasternodeOutpoint().ToStringShort()); return false; } } } // we have votes by other masternodes only (so far), let's continue and see who will win it1->second.insert(txHash); } else { std::set setHashes; setHashes.insert(txHash); mapVotedOutpoints.insert(std::make_pair(vote.GetOutpoint(), setHashes)); } CTxLockCandidate& txLockCandidate = it->second; if(!txLockCandidate.AddVote(vote)) { // this should never happen return false; } int nSignatures = txLockCandidate.CountVotes(); int nSignaturesMax = txLockCandidate.txLockRequest.GetMaxSignatures(); LogPrint("instantsend", "CInstantSend::ProcessTxLockVote -- Transaction Lock signatures count: %d/%d, vote hash=%s\n", nSignatures, nSignaturesMax, vote.GetHash().ToString()); TryToFinalizeLockCandidate(txLockCandidate); vote.Relay(); return true; } void CInstantSend::ProcessOrphanTxLockVotes() { LOCK2(cs_main, cs_instantsend); std::map::iterator it = mapTxLockVotesOrphan.begin(); while(it != mapTxLockVotesOrphan.end()) { if(ProcessTxLockVote(NULL, it->second)) { mapTxLockVotesOrphan.erase(it++); } else { ++it; } } } bool CInstantSend::IsEnoughOrphanVotesForTx(const CTxLockRequest& txLockRequest) { // There could be a situation when we already have quite a lot of votes // but tx lock request still wasn't received. Let's scan through // orphan votes to check if this is the case. BOOST_FOREACH(const CTxIn& txin, txLockRequest.vin) { if(!IsEnoughOrphanVotesForTxAndOutPoint(txLockRequest.GetHash(), txin.prevout)) { return false; } } return true; } bool CInstantSend::IsEnoughOrphanVotesForTxAndOutPoint(const uint256& txHash, const COutPoint& outpoint) { // Scan orphan votes to check if this outpoint has enough orphan votes to be locked in some tx. LOCK2(cs_main, cs_instantsend); int nCountVotes = 0; std::map::iterator it = mapTxLockVotesOrphan.begin(); while(it != mapTxLockVotesOrphan.end()) { if(it->second.GetTxHash() == txHash && it->second.GetOutpoint() == outpoint) { nCountVotes++; if(nCountVotes >= COutPointLock::SIGNATURES_REQUIRED) { return true; } } ++it; } return false; } void CInstantSend::TryToFinalizeLockCandidate(const CTxLockCandidate& txLockCandidate) { LOCK2(cs_main, cs_instantsend); uint256 txHash = txLockCandidate.txLockRequest.GetHash(); if(txLockCandidate.IsAllOutPointsReady() && !IsLockedInstantSendTransaction(txHash)) { // we have enough votes now LogPrint("instantsend", "CInstantSend::TryToFinalizeLockCandidate -- Transaction Lock is ready to complete, txid=%s\n", txHash.ToString()); if(ResolveConflicts(txLockCandidate, Params().GetConsensus().nInstantSendKeepLock)) { LockTransactionInputs(txLockCandidate); UpdateLockedTransaction(txLockCandidate); } } } void CInstantSend::UpdateLockedTransaction(const CTxLockCandidate& txLockCandidate) { LOCK(cs_instantsend); uint256 txHash = txLockCandidate.GetHash(); if(!IsLockedInstantSendTransaction(txHash)) return; // not a locked tx, do not update/notify #ifdef ENABLE_WALLET if(pwalletMain && pwalletMain->UpdatedTransaction(txHash)) { // bumping this to update UI nCompleteTXLocks++; // notify an external script once threshold is reached std::string strCmd = GetArg("-instantsendnotify", ""); if(!strCmd.empty()) { boost::replace_all(strCmd, "%s", txHash.GetHex()); boost::thread t(runCommand, strCmd); // thread runs free } } #endif GetMainSignals().NotifyTransactionLock(txLockCandidate.txLockRequest); LogPrint("instantsend", "CInstantSend::UpdateLockedTransaction -- done, txid=%s\n", txHash.ToString()); } void CInstantSend::LockTransactionInputs(const CTxLockCandidate& txLockCandidate) { LOCK(cs_instantsend); uint256 txHash = txLockCandidate.GetHash(); if(!txLockCandidate.IsAllOutPointsReady()) return; std::map::const_iterator it = txLockCandidate.mapOutPointLocks.begin(); while(it != txLockCandidate.mapOutPointLocks.end()) { mapLockedOutpoints.insert(std::make_pair(it->first, txHash)); ++it; } LogPrint("instantsend", "CInstantSend::LockTransactionInputs -- done, txid=%s\n", txHash.ToString()); } bool CInstantSend::GetLockedOutPointTxHash(const COutPoint& outpoint, uint256& hashRet) { LOCK(cs_instantsend); std::map::iterator it = mapLockedOutpoints.find(outpoint); if(it == mapLockedOutpoints.end()) return false; hashRet = it->second; return true; } bool CInstantSend::ResolveConflicts(const CTxLockCandidate& txLockCandidate, int nMaxBlocks) { if(nMaxBlocks < 1) return false; LOCK2(cs_main, cs_instantsend); uint256 txHash = txLockCandidate.GetHash(); // make sure the lock is ready if(!txLockCandidate.IsAllOutPointsReady()) return true; // not an error LOCK(mempool.cs); // protect mempool.mapNextTx, mempool.mapTx bool fMempoolConflict = false; BOOST_FOREACH(const CTxIn& txin, txLockCandidate.txLockRequest.vin) { uint256 hashConflicting; if(GetLockedOutPointTxHash(txin.prevout, hashConflicting) && txHash != hashConflicting) { // conflicting with complete lock, ignore current one LogPrintf("CInstantSend::ResolveConflicts -- WARNING: Found conflicting completed Transaction Lock, skipping current one, txid=%s, conflicting txid=%s\n", txHash.ToString(), hashConflicting.ToString()); return false; // can't/shouldn't do anything } else if (mempool.mapNextTx.count(txin.prevout)) { // check if it's in mempool hashConflicting = mempool.mapNextTx[txin.prevout].ptx->GetHash(); if(txHash == hashConflicting) continue; // matches current, not a conflict, skip to next txin // conflicting with tx in mempool fMempoolConflict = true; if(HasTxLockRequest(hashConflicting)) { // There can be only one completed lock, the other lock request should never complete LogPrintf("CInstantSend::ResolveConflicts -- WARNING: Found conflicting Transaction Lock Request, replacing by completed Transaction Lock, txid=%s, conflicting txid=%s\n", txHash.ToString(), hashConflicting.ToString()); } else { // If this lock is completed, we don't really care about normal conflicting txes. LogPrintf("CInstantSend::ResolveConflicts -- WARNING: Found conflicting transaction, replacing by completed Transaction Lock, txid=%s, conflicting txid=%s\n", txHash.ToString(), hashConflicting.ToString()); } } } // FOREACH if(fMempoolConflict) { std::list removed; // remove every tx conflicting with current Transaction Lock Request mempool.removeConflicts(txLockCandidate.txLockRequest, removed); // and try to accept it in mempool again CValidationState state; bool fMissingInputs = false; if(!AcceptToMemoryPool(mempool, state, txLockCandidate.txLockRequest, true, &fMissingInputs)) { LogPrintf("CInstantSend::ResolveConflicts -- ERROR: Failed to accept completed Transaction Lock to mempool, txid=%s\n", txHash.ToString()); return false; } LogPrintf("CInstantSend::ResolveConflicts -- Accepted completed Transaction Lock, txid=%s\n", txHash.ToString()); return true; } // No conflicts were found so far, check to see if it was already included in block CTransaction txTmp; uint256 hashBlock; if(GetTransaction(txHash, txTmp, Params().GetConsensus(), hashBlock, true) && hashBlock != uint256()) { LogPrint("instantsend", "CInstantSend::ResolveConflicts -- Done, %s is included in block %s\n", txHash.ToString(), hashBlock.ToString()); return true; } // Not in block yet, make sure all its inputs are still unspent BOOST_FOREACH(const CTxIn& txin, txLockCandidate.txLockRequest.vin) { CCoins coins; if(!pcoinsTip->GetCoins(txin.prevout.hash, coins) || (unsigned int)txin.prevout.n>=coins.vout.size() || coins.vout[txin.prevout.n].IsNull()) { // Not in UTXO anymore? A conflicting tx was mined while we were waiting for votes. // Reprocess tip to make sure tx for this lock is included. LogPrintf("CTxLockRequest::ResolveConflicts -- Failed to find UTXO %s - disconnecting tip...\n", txin.prevout.ToStringShort()); if(!DisconnectBlocks(1)) { return false; } // Recursively check at "new" old height. Conflicting tx should be rejected by AcceptToMemoryPool. ResolveConflicts(txLockCandidate, nMaxBlocks - 1); LogPrintf("CTxLockRequest::ResolveConflicts -- Failed to find UTXO %s - activating best chain...\n", txin.prevout.ToStringShort()); // Activate best chain, block which includes conflicting tx should be rejected by ConnectBlock. CValidationState state; if(!ActivateBestChain(state, Params()) || !state.IsValid()) { LogPrintf("CTxLockRequest::ResolveConflicts -- ActivateBestChain failed, txid=%s\n", txin.prevout.ToStringShort()); return false; } LogPrintf("CTxLockRequest::ResolveConflicts -- Failed to find UTXO %s - fixed!\n", txin.prevout.ToStringShort()); } } LogPrint("instantsend", "CInstantSend::ResolveConflicts -- Done, txid=%s\n", txHash.ToString()); return true; } int64_t CInstantSend::GetAverageMasternodeOrphanVoteTime() { LOCK(cs_instantsend); // NOTE: should never actually call this function when mapMasternodeOrphanVotes is empty if(mapMasternodeOrphanVotes.empty()) return 0; std::map::iterator it = mapMasternodeOrphanVotes.begin(); int64_t total = 0; while(it != mapMasternodeOrphanVotes.end()) { total+= it->second; ++it; } return total / mapMasternodeOrphanVotes.size(); } void CInstantSend::CheckAndRemove() { if(!pCurrentBlockIndex) return; LOCK(cs_instantsend); std::map::iterator itLockCandidate = mapTxLockCandidates.begin(); // remove expired candidates while(itLockCandidate != mapTxLockCandidates.end()) { CTxLockCandidate &txLockCandidate = itLockCandidate->second; uint256 txHash = txLockCandidate.GetHash(); if(txLockCandidate.IsExpired(pCurrentBlockIndex->nHeight)) { LogPrintf("CInstantSend::CheckAndRemove -- Removing expired Transaction Lock Candidate: txid=%s\n", txHash.ToString()); std::map::iterator itOutpointLock = txLockCandidate.mapOutPointLocks.begin(); while(itOutpointLock != txLockCandidate.mapOutPointLocks.end()) { mapLockedOutpoints.erase(itOutpointLock->first); mapVotedOutpoints.erase(itOutpointLock->first); ++itOutpointLock; } mapLockRequestAccepted.erase(txHash); mapLockRequestRejected.erase(txHash); mapTxLockCandidates.erase(itLockCandidate++); } else { ++itLockCandidate; } } // remove expired votes std::map::iterator itVote = mapTxLockVotes.begin(); while(itVote != mapTxLockVotes.end()) { if(itVote->second.IsExpired(pCurrentBlockIndex->nHeight)) { LogPrint("instantsend", "CInstantSend::CheckAndRemove -- Removing expired vote: txid=%s masternode=%s\n", itVote->second.GetTxHash().ToString(), itVote->second.GetMasternodeOutpoint().ToStringShort()); mapTxLockVotes.erase(itVote++); } else { ++itVote; } } // remove expired orphan votes std::map::iterator itOrphanVote = mapTxLockVotesOrphan.begin(); while(itOrphanVote != mapTxLockVotesOrphan.end()) { if(GetTime() - itOrphanVote->second.GetTimeCreated() > ORPHAN_VOTE_SECONDS) { LogPrint("instantsend", "CInstantSend::CheckAndRemove -- Removing expired orphan vote: txid=%s masternode=%s\n", itOrphanVote->second.GetTxHash().ToString(), itOrphanVote->second.GetMasternodeOutpoint().ToStringShort()); mapTxLockVotes.erase(itOrphanVote->first); mapTxLockVotesOrphan.erase(itOrphanVote++); } else { ++itOrphanVote; } } // remove expired masternode orphan votes (DOS protection) std::map::iterator itMasternodeOrphan = mapMasternodeOrphanVotes.begin(); while(itMasternodeOrphan != mapMasternodeOrphanVotes.end()) { if(itMasternodeOrphan->second < GetTime()) { LogPrint("instantsend", "CInstantSend::CheckAndRemove -- Removing expired orphan masternode vote: masternode=%s\n", itMasternodeOrphan->first.ToStringShort()); mapMasternodeOrphanVotes.erase(itMasternodeOrphan++); } else { ++itMasternodeOrphan; } } LogPrintf("CInstantSend::CheckAndRemove -- %s\n", ToString()); } bool CInstantSend::AlreadyHave(const uint256& hash) { LOCK(cs_instantsend); return mapLockRequestAccepted.count(hash) || mapLockRequestRejected.count(hash) || mapTxLockVotes.count(hash); } void CInstantSend::AcceptLockRequest(const CTxLockRequest& txLockRequest) { LOCK(cs_instantsend); mapLockRequestAccepted.insert(make_pair(txLockRequest.GetHash(), txLockRequest)); } void CInstantSend::RejectLockRequest(const CTxLockRequest& txLockRequest) { LOCK(cs_instantsend); mapLockRequestRejected.insert(make_pair(txLockRequest.GetHash(), txLockRequest)); } bool CInstantSend::HasTxLockRequest(const uint256& txHash) { CTxLockRequest txLockRequestTmp; return GetTxLockRequest(txHash, txLockRequestTmp); } bool CInstantSend::GetTxLockRequest(const uint256& txHash, CTxLockRequest& txLockRequestRet) { LOCK(cs_instantsend); std::map::iterator it = mapTxLockCandidates.find(txHash); if(it == mapTxLockCandidates.end()) return false; txLockRequestRet = it->second.txLockRequest; return true; } bool CInstantSend::GetTxLockVote(const uint256& hash, CTxLockVote& txLockVoteRet) { LOCK(cs_instantsend); std::map::iterator it = mapTxLockVotes.find(hash); if(it == mapTxLockVotes.end()) return false; txLockVoteRet = it->second; return true; } bool CInstantSend::IsInstantSendReadyToLock(const uint256& txHash) { if(!fEnableInstantSend || fLargeWorkForkFound || fLargeWorkInvalidChainFound || !sporkManager.IsSporkActive(SPORK_2_INSTANTSEND_ENABLED)) return false; LOCK(cs_instantsend); // There must be a successfully verified lock request // and all outputs must be locked (i.e. have enough signatures) std::map::iterator it = mapTxLockCandidates.find(txHash); return it != mapTxLockCandidates.end() && it->second.IsAllOutPointsReady(); } bool CInstantSend::IsLockedInstantSendTransaction(const uint256& txHash) { if(!fEnableInstantSend || fLargeWorkForkFound || fLargeWorkInvalidChainFound || !sporkManager.IsSporkActive(SPORK_2_INSTANTSEND_ENABLED)) return false; LOCK(cs_instantsend); // there must be a lock candidate std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); if(itLockCandidate == mapTxLockCandidates.end()) return false; // which should have outpoints if(itLockCandidate->second.mapOutPointLocks.empty()) return false; // and all of these outputs must be included in mapLockedOutpoints with correct hash std::map::iterator itOutpointLock = itLockCandidate->second.mapOutPointLocks.begin(); while(itOutpointLock != itLockCandidate->second.mapOutPointLocks.end()) { uint256 hashLocked; if(!GetLockedOutPointTxHash(itOutpointLock->first, hashLocked) || hashLocked != txHash) return false; ++itOutpointLock; } return true; } int CInstantSend::GetTransactionLockSignatures(const uint256& txHash) { if(!fEnableInstantSend) return -1; if(fLargeWorkForkFound || fLargeWorkInvalidChainFound) return -2; if(!sporkManager.IsSporkActive(SPORK_2_INSTANTSEND_ENABLED)) return -3; LOCK(cs_instantsend); std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); if(itLockCandidate != mapTxLockCandidates.end()) { return itLockCandidate->second.CountVotes(); } return -1; } bool CInstantSend::IsTxLockRequestTimedOut(const uint256& txHash) { if(!fEnableInstantSend) return false; LOCK(cs_instantsend); std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); if (itLockCandidate != mapTxLockCandidates.end()) { return !itLockCandidate->second.IsAllOutPointsReady() && itLockCandidate->second.txLockRequest.IsTimedOut(); } return false; } void CInstantSend::Relay(const uint256& txHash) { LOCK(cs_instantsend); std::map::const_iterator itLockCandidate = mapTxLockCandidates.find(txHash); if (itLockCandidate != mapTxLockCandidates.end()) { itLockCandidate->second.Relay(); } } void CInstantSend::UpdatedBlockTip(const CBlockIndex *pindex) { pCurrentBlockIndex = pindex; } void CInstantSend::SyncTransaction(const CTransaction& tx, const CBlock* pblock) { // Update lock candidates and votes if corresponding tx confirmed // or went from confirmed to 0-confirmed or conflicted. if (tx.IsCoinBase()) return; LOCK2(cs_main, cs_instantsend); uint256 txHash = tx.GetHash(); // When tx is 0-confirmed or conflicted, pblock is NULL and nHeightNew should be set to -1 CBlockIndex* pblockindex = NULL; if(pblock) { uint256 blockHash = pblock->GetHash(); BlockMap::iterator mi = mapBlockIndex.find(blockHash); if(mi == mapBlockIndex.end() || !mi->second) { // shouldn't happen LogPrint("instantsend", "CTxLockRequest::SyncTransaction -- Failed to find block %s\n", blockHash.ToString()); return; } pblockindex = mi->second; } int nHeightNew = pblockindex ? pblockindex->nHeight : -1; LogPrint("instantsend", "CInstantSend::SyncTransaction -- txid=%s nHeightNew=%d\n", txHash.ToString(), nHeightNew); // Check lock candidates std::map::iterator itLockCandidate = mapTxLockCandidates.find(txHash); if(itLockCandidate != mapTxLockCandidates.end()) { LogPrint("instantsend", "CInstantSend::SyncTransaction -- txid=%s nHeightNew=%d lock candidate updated\n", txHash.ToString(), nHeightNew); itLockCandidate->second.SetConfirmedHeight(nHeightNew); // Loop through outpoint locks std::map::iterator itOutpointLock = itLockCandidate->second.mapOutPointLocks.begin(); while(itOutpointLock != itLockCandidate->second.mapOutPointLocks.end()) { // Check corresponding lock votes std::vector vVotes = itOutpointLock->second.GetVotes(); std::vector::iterator itVote = vVotes.begin(); std::map::iterator it; while(itVote != vVotes.end()) { uint256 nVoteHash = itVote->GetHash(); LogPrint("instantsend", "CInstantSend::SyncTransaction -- txid=%s nHeightNew=%d vote %s updated\n", txHash.ToString(), nHeightNew, nVoteHash.ToString()); it = mapTxLockVotes.find(nVoteHash); if(it != mapTxLockVotes.end()) { it->second.SetConfirmedHeight(nHeightNew); } ++itVote; } ++itOutpointLock; } } // check orphan votes std::map::iterator itOrphanVote = mapTxLockVotesOrphan.begin(); while(itOrphanVote != mapTxLockVotesOrphan.end()) { if(itOrphanVote->second.GetTxHash() == txHash) { LogPrint("instantsend", "CInstantSend::SyncTransaction -- txid=%s nHeightNew=%d vote %s updated\n", txHash.ToString(), nHeightNew, itOrphanVote->first.ToString()); mapTxLockVotes[itOrphanVote->first].SetConfirmedHeight(nHeightNew); } ++itOrphanVote; } } std::string CInstantSend::ToString() { LOCK(cs_instantsend); return strprintf("Lock Candidates: %llu, Votes %llu", mapTxLockCandidates.size(), mapTxLockVotes.size()); } // // CTxLockRequest // bool CTxLockRequest::IsValid(bool fRequireUnspent) const { if(vout.size() < 1) return false; if(vin.size() > WARN_MANY_INPUTS) { LogPrint("instantsend", "CTxLockRequest::IsValid -- WARNING: Too many inputs: tx=%s", ToString()); } LOCK(cs_main); if(!CheckFinalTx(*this)) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Transaction is not final: tx=%s", ToString()); return false; } CAmount nValueIn = 0; CAmount nValueOut = 0; BOOST_FOREACH(const CTxOut& txout, vout) { // InstantSend supports normal scripts and unspendable (i.e. data) scripts. // TODO: Look into other script types that are normal and can be included if(!txout.scriptPubKey.IsNormalPaymentScript() && !txout.scriptPubKey.IsUnspendable()) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Invalid Script %s", ToString()); return false; } nValueOut += txout.nValue; } BOOST_FOREACH(const CTxIn& txin, vin) { CCoins coins; int nPrevoutHeight = 0; CAmount nValue = 0; if(!pcoinsTip->GetCoins(txin.prevout.hash, coins) || (unsigned int)txin.prevout.n>=coins.vout.size() || coins.vout[txin.prevout.n].IsNull()) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Failed to find UTXO %s\n", txin.prevout.ToStringShort()); // Normally above sould be enough, but in case we are reprocessing this because of // a lot of legit orphan votes we should also check already spent outpoints. if(fRequireUnspent) return false; CTransaction txOutpointCreated; uint256 nHashOutpointConfirmed; if(!GetTransaction(txin.prevout.hash, txOutpointCreated, Params().GetConsensus(), nHashOutpointConfirmed, true) || nHashOutpointConfirmed == uint256()) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Failed to find outpoint %s\n", txin.prevout.ToStringShort()); return false; } if(txin.prevout.n >= txOutpointCreated.vout.size()) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Outpoint %s is out of bounds, size() = %lld\n", txin.prevout.ToStringShort(), txOutpointCreated.vout.size()); return false; } BlockMap::iterator mi = mapBlockIndex.find(nHashOutpointConfirmed); if(mi == mapBlockIndex.end() || !mi->second) { // shouldn't happen LogPrint("instantsend", "CTxLockRequest::IsValid -- Failed to find block %s for outpoint %s\n", nHashOutpointConfirmed.ToString(), txin.prevout.ToStringShort()); return false; } nPrevoutHeight = mi->second->nHeight; nValue = txOutpointCreated.vout[txin.prevout.n].nValue; } else { nPrevoutHeight = coins.nHeight; nValue = coins.vout[txin.prevout.n].nValue; } int nTxAge = chainActive.Height() - nPrevoutHeight + 1; // 1 less than the "send IX" gui requires, in case of a block propagating the network at the time int nConfirmationsRequired = INSTANTSEND_CONFIRMATIONS_REQUIRED - 1; if(nTxAge < nConfirmationsRequired) { LogPrint("instantsend", "CTxLockRequest::IsValid -- outpoint %s too new: nTxAge=%d, nConfirmationsRequired=%d, txid=%s\n", txin.prevout.ToStringShort(), nTxAge, nConfirmationsRequired, GetHash().ToString()); return false; } nValueIn += nValue; } if(nValueOut > sporkManager.GetSporkValue(SPORK_5_INSTANTSEND_MAX_VALUE)*COIN) { LogPrint("instantsend", "CTxLockRequest::IsValid -- Transaction value too high: nValueOut=%d, tx=%s", nValueOut, ToString()); return false; } if(nValueIn - nValueOut < GetMinFee()) { LogPrint("instantsend", "CTxLockRequest::IsValid -- did not include enough fees in transaction: fees=%d, tx=%s", nValueOut - nValueIn, ToString()); return false; } return true; } CAmount CTxLockRequest::GetMinFee() const { CAmount nMinFee = MIN_FEE; return std::max(nMinFee, CAmount(vin.size() * nMinFee)); } int CTxLockRequest::GetMaxSignatures() const { return vin.size() * COutPointLock::SIGNATURES_TOTAL; } bool CTxLockRequest::IsTimedOut() const { return GetTime() - nTimeCreated > TIMEOUT_SECONDS; } // // CTxLockVote // bool CTxLockVote::IsValid(CNode* pnode) const { if(!mnodeman.Has(CTxIn(outpointMasternode))) { LogPrint("instantsend", "CTxLockVote::IsValid -- Unknown masternode %s\n", outpointMasternode.ToStringShort()); mnodeman.AskForMN(pnode, CTxIn(outpointMasternode)); return false; } int nPrevoutHeight = GetUTXOHeight(outpoint); if(nPrevoutHeight == -1) { LogPrint("instantsend", "CTxLockVote::IsValid -- Failed to find UTXO %s\n", outpoint.ToStringShort()); // Validating utxo set is not enough, votes can arrive after outpoint was already spent, // if lock request was mined. We should process them too to count them later if they are legit. CTransaction txOutpointCreated; uint256 nHashOutpointConfirmed; if(!GetTransaction(outpoint.hash, txOutpointCreated, Params().GetConsensus(), nHashOutpointConfirmed, true) || nHashOutpointConfirmed == uint256()) { LogPrint("instantsend", "CTxLockVote::IsValid -- Failed to find outpoint %s\n", outpoint.ToStringShort()); return false; } LOCK(cs_main); BlockMap::iterator mi = mapBlockIndex.find(nHashOutpointConfirmed); if(mi == mapBlockIndex.end() || !mi->second) { // not on this chain? LogPrint("instantsend", "CTxLockVote::IsValid -- Failed to find block %s for outpoint %s\n", nHashOutpointConfirmed.ToString(), outpoint.ToStringShort()); return false; } nPrevoutHeight = mi->second->nHeight; } int nLockInputHeight = nPrevoutHeight + 4; int n = mnodeman.GetMasternodeRank(CTxIn(outpointMasternode), nLockInputHeight, MIN_INSTANTSEND_PROTO_VERSION); if(n == -1) { //can be caused by past versions trying to vote with an invalid protocol LogPrint("instantsend", "CTxLockVote::IsValid -- Can't calculate rank for masternode %s\n", outpointMasternode.ToStringShort()); return false; } LogPrint("instantsend", "CTxLockVote::IsValid -- Masternode %s, rank=%d\n", outpointMasternode.ToStringShort(), n); int nSignaturesTotal = COutPointLock::SIGNATURES_TOTAL; if(n > nSignaturesTotal) { LogPrint("instantsend", "CTxLockVote::IsValid -- Masternode %s is not in the top %d (%d), vote hash=%s\n", outpointMasternode.ToStringShort(), nSignaturesTotal, n, GetHash().ToString()); return false; } if(!CheckSignature()) { LogPrintf("CTxLockVote::IsValid -- Signature invalid\n"); return false; } return true; } uint256 CTxLockVote::GetHash() const { CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION); ss << txHash; ss << outpoint; ss << outpointMasternode; return ss.GetHash(); } bool CTxLockVote::CheckSignature() const { std::string strError; std::string strMessage = txHash.ToString() + outpoint.ToStringShort(); masternode_info_t infoMn = mnodeman.GetMasternodeInfo(CTxIn(outpointMasternode)); if(!infoMn.fInfoValid) { LogPrintf("CTxLockVote::CheckSignature -- Unknown Masternode: masternode=%s\n", outpointMasternode.ToString()); return false; } if(!CMessageSigner::VerifyMessage(infoMn.pubKeyMasternode, vchMasternodeSignature, strMessage, strError)) { LogPrintf("CTxLockVote::CheckSignature -- VerifyMessage() failed, error: %s\n", strError); return false; } return true; } bool CTxLockVote::Sign() { std::string strError; std::string strMessage = txHash.ToString() + outpoint.ToStringShort(); if(!CMessageSigner::SignMessage(strMessage, vchMasternodeSignature, activeMasternode.keyMasternode)) { LogPrintf("CTxLockVote::Sign -- SignMessage() failed\n"); return false; } if(!CMessageSigner::VerifyMessage(activeMasternode.pubKeyMasternode, vchMasternodeSignature, strMessage, strError)) { LogPrintf("CTxLockVote::Sign -- VerifyMessage() failed, error: %s\n", strError); return false; } return true; } void CTxLockVote::Relay() const { CInv inv(MSG_TXLOCK_VOTE, GetHash()); g_connman->RelayInv(inv); } bool CTxLockVote::IsExpired(int nHeight) const { // Locks and votes expire nInstantSendKeepLock blocks after the block corresponding tx was included into. return (nConfirmedHeight != -1) && (nHeight - nConfirmedHeight > Params().GetConsensus().nInstantSendKeepLock); } // // COutPointLock // bool COutPointLock::AddVote(const CTxLockVote& vote) { if(mapMasternodeVotes.count(vote.GetMasternodeOutpoint())) return false; mapMasternodeVotes.insert(std::make_pair(vote.GetMasternodeOutpoint(), vote)); return true; } std::vector COutPointLock::GetVotes() const { std::vector vRet; std::map::const_iterator itVote = mapMasternodeVotes.begin(); while(itVote != mapMasternodeVotes.end()) { vRet.push_back(itVote->second); ++itVote; } return vRet; } bool COutPointLock::HasMasternodeVoted(const COutPoint& outpointMasternodeIn) const { return mapMasternodeVotes.count(outpointMasternodeIn); } void COutPointLock::Relay() const { std::map::const_iterator itVote = mapMasternodeVotes.begin(); while(itVote != mapMasternodeVotes.end()) { itVote->second.Relay(); ++itVote; } } // // CTxLockCandidate // void CTxLockCandidate::AddOutPointLock(const COutPoint& outpoint) { mapOutPointLocks.insert(make_pair(outpoint, COutPointLock(outpoint))); } bool CTxLockCandidate::AddVote(const CTxLockVote& vote) { std::map::iterator it = mapOutPointLocks.find(vote.GetOutpoint()); if(it == mapOutPointLocks.end()) return false; return it->second.AddVote(vote); } bool CTxLockCandidate::IsAllOutPointsReady() const { if(mapOutPointLocks.empty()) return false; std::map::const_iterator it = mapOutPointLocks.begin(); while(it != mapOutPointLocks.end()) { if(!it->second.IsReady()) return false; ++it; } return true; } bool CTxLockCandidate::HasMasternodeVoted(const COutPoint& outpointIn, const COutPoint& outpointMasternodeIn) { std::map::iterator it = mapOutPointLocks.find(outpointIn); return it !=mapOutPointLocks.end() && it->second.HasMasternodeVoted(outpointMasternodeIn); } int CTxLockCandidate::CountVotes() const { // Note: do NOT use vote count to figure out if tx is locked, use IsAllOutPointsReady() instead int nCountVotes = 0; std::map::const_iterator it = mapOutPointLocks.begin(); while(it != mapOutPointLocks.end()) { nCountVotes += it->second.CountVotes(); ++it; } return nCountVotes; } bool CTxLockCandidate::IsExpired(int nHeight) const { // Locks and votes expire nInstantSendKeepLock blocks after the block corresponding tx was included into. return (nConfirmedHeight != -1) && (nHeight - nConfirmedHeight > Params().GetConsensus().nInstantSendKeepLock); } void CTxLockCandidate::Relay() const { g_connman->RelayTransaction(txLockRequest); std::map::const_iterator itOutpointLock = mapOutPointLocks.begin(); while(itOutpointLock != mapOutPointLocks.end()) { itOutpointLock->second.Relay(); ++itOutpointLock; } }