diff options
Diffstat (limited to 'src/wallet')
| -rw-r--r-- | src/wallet/rpcwallet.cpp | 258 | ||||
| -rw-r--r-- | src/wallet/wallet.cpp | 67 | ||||
| -rw-r--r-- | src/wallet/wallet.h | 6 |
3 files changed, 331 insertions, 0 deletions
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp index ffe0827bef..dc2c6d292e 100644 --- a/src/wallet/rpcwallet.cpp +++ b/src/wallet/rpcwallet.cpp @@ -11,8 +11,10 @@ #include "init.h" #include "validation.h" #include "net.h" +#include "policy/policy.h" #include "policy/rbf.h" #include "rpc/server.h" +#include "script/sign.h" #include "timedata.h" #include "util.h" #include "utilmoneystr.h" @@ -2595,6 +2597,261 @@ UniValue fundrawtransaction(const JSONRPCRequest& request) return result; } +UniValue bumpfee(const JSONRPCRequest& request) +{ + if (!EnsureWalletIsAvailable(request.fHelp)) { + return NullUniValue; + } + + if (request.fHelp || request.params.size() < 1 || request.params.size() > 2) { + throw runtime_error( + "bumpfee \"txid\" ( options ) \n" + "\nBumps the fee of an opt-in-RBF transaction T, replacing it with a new transaction B.\n" + "An opt-in RBF transaction with the given txid must be in the wallet.\n" + "The command will pay the additional fee by decreasing (or perhaps removing) its change output.\n" + "If the change output is not big enough to cover the increased fee, the command will currently fail\n" + "instead of adding new inputs to compensate. (A future implementation could improve this.)\n" + "The command will fail if the wallet or mempool contains a transaction that spends one of T's outputs.\n" + "By default, the new fee will be calculated automatically using estimatefee.\n" + "The user can specify a confirmation target for estimatefee.\n" + "Alternatively, the user can specify totalFee, or use RPC setpaytxfee to set a higher fee rate.\n" + "At a minimum, the new fee rate must be high enough to pay a new relay fee (relay fee amount returned\n" + "by getnetworkinfo RPC) and to enter the node's mempool.\n" + "\nArguments:\n" + "1. txid (string, required) The txid to be bumped\n" + "2. options (object, optional)\n" + " {\n" + " \"confTarget\" (numeric, optional) Confirmation target (in blocks)\n" + " \"totalFee\" (numeric, optional) Total fee (NOT feerate) to pay, in satoshis.\n" + " In rare cases, the actual fee paid might be slightly higher than the specified\n" + " totalFee if the tx change output has to be removed because it is too close to\n" + " the dust threshold.\n" + " \"replaceable\" (boolean, optional, default true) Whether the new transaction should still be\n" + " marked bip-125 replaceable. If true, the sequence numbers in the transaction will\n" + " be left unchanged from the original. If false, any input sequence numbers in the\n" + " original transaction that were less than 0xfffffffe will be increased to 0xfffffffe\n" + " so the new transaction will not be explicitly bip-125 replaceable (though it may\n" + " still be replacable in practice, for example if it has unconfirmed ancestors which\n" + " are replaceable).\n" + " }\n" + "\nResult:\n" + "{\n" + " \"txid\": \"value\", (string) The id of the new transaction\n" + " \"oldfee\": n, (numeric) Fee of the replaced transaction\n" + " \"fee\": n, (numeric) Fee of the new transaction\n" + "}\n" + "\nExamples:\n" + "\nBump the fee, get the new transaction\'s txid\n" + + HelpExampleCli("bumpfee", "<txid>")); + } + + RPCTypeCheck(request.params, boost::assign::list_of(UniValue::VSTR)(UniValue::VOBJ)); + uint256 hash; + hash.SetHex(request.params[0].get_str()); + + // retrieve the original tx from the wallet + LOCK2(cs_main, pwalletMain->cs_wallet); + EnsureWalletIsUnlocked(); + if (!pwalletMain->mapWallet.count(hash)) { + throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid or non-wallet transaction id"); + } + CWalletTx& wtx = pwalletMain->mapWallet[hash]; + + if (pwalletMain->HasWalletSpend(hash)) { + throw JSONRPCError(RPC_MISC_ERROR, "Transaction has descendants in the wallet"); + } + + { + LOCK(mempool.cs); + auto it = mempool.mapTx.find(hash); + if (it != mempool.mapTx.end() && it->GetCountWithDescendants() > 1) { + throw JSONRPCError(RPC_MISC_ERROR, "Transaction has descendants in the mempool"); + } + } + + if (wtx.GetDepthInMainChain() != 0) { + throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction has been mined, or is conflicted with a mined transaction"); + } + + if (!SignalsOptInRBF(wtx)) { + throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction is not BIP 125 replaceable"); + } + + if (wtx.mapValue.count("replaced_by_txid")) { + throw JSONRPCError(RPC_INVALID_REQUEST, strprintf("Cannot bump transaction %s which was already bumped by transaction %s", hash.ToString(), wtx.mapValue.at("replaced_by_txid"))); + } + + // check that original tx consists entirely of our inputs + // if not, we can't bump the fee, because the wallet has no way of knowing the value of the other inputs (thus the fee) + if (!pwalletMain->IsAllFromMe(wtx, ISMINE_SPENDABLE)) { + throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction contains inputs that don't belong to this wallet"); + } + + // figure out which output was change + // if there was no change output or multiple change outputs, fail + int nOutput = -1; + for (size_t i = 0; i < wtx.tx->vout.size(); ++i) { + if (pwalletMain->IsChange(wtx.tx->vout[i])) { + if (nOutput != -1) { + throw JSONRPCError(RPC_MISC_ERROR, "Transaction has multiple change outputs"); + } + nOutput = i; + } + } + if (nOutput == -1) { + throw JSONRPCError(RPC_MISC_ERROR, "Transaction does not have a change output"); + } + + // optional parameters + bool specifiedConfirmTarget = false; + int newConfirmTarget = nTxConfirmTarget; + CAmount totalFee = 0; + bool replaceable = true; + if (request.params.size() > 1) { + UniValue options = request.params[1]; + RPCTypeCheckObj(options, + { + {"confTarget", UniValueType(UniValue::VNUM)}, + {"totalFee", UniValueType(UniValue::VNUM)}, + {"replaceable", UniValueType(UniValue::VBOOL)}, + }, + true, true); + + if (options.exists("confTarget") && options.exists("totalFee")) { + throw JSONRPCError(RPC_INVALID_PARAMETER, "confTarget and totalFee options should not both be set. Please provide either a confirmation target for fee estimation or an explicit total fee for the transaction."); + } else if (options.exists("confTarget")) { + specifiedConfirmTarget = true; + newConfirmTarget = options["confTarget"].get_int(); + if (newConfirmTarget <= 0) { // upper-bound will be checked by estimatefee/smartfee + throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid confTarget (cannot be <= 0)"); + } + } else if (options.exists("totalFee")) { + totalFee = options["totalFee"].get_int64(); + if (totalFee <= 0) { + throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid totalFee (cannot be <= 0)"); + } else if (totalFee > maxTxFee) { + throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid totalFee (cannot be higher than maxTxFee)"); + } + } + + if (options.exists("replaceable")) { + replaceable = options["replaceable"].get_bool(); + } + } + + // signature sizes can vary by a byte, so add 1 for each input when calculating the new fee + int64_t txSize = GetVirtualTransactionSize(*(wtx.tx)); + const int64_t maxNewTxSize = txSize + wtx.tx->vin.size(); + + // calculate the old fee and fee-rate + CAmount nOldFee = wtx.GetDebit(ISMINE_SPENDABLE) - wtx.tx->GetValueOut(); + CFeeRate nOldFeeRate(nOldFee, txSize); + CAmount nNewFee; + CFeeRate nNewFeeRate; + + if (totalFee > 0) { + CAmount minTotalFee = nOldFeeRate.GetFee(maxNewTxSize) + minRelayTxFee.GetFee(maxNewTxSize); + if (totalFee < minTotalFee) { + throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid totalFee, must be at least %s (oldFee %s + relayFee %s)", FormatMoney(minTotalFee), nOldFeeRate.GetFee(maxNewTxSize), minRelayTxFee.GetFee(maxNewTxSize))); + } + nNewFee = totalFee; + nNewFeeRate = CFeeRate(totalFee, maxNewTxSize); + } else { + // use the user-defined payTxFee if possible, otherwise use smartfee / fallbackfee + if (!specifiedConfirmTarget && payTxFee.GetFeePerK() != 0) { + nNewFeeRate = payTxFee; + } else { + nNewFeeRate = mempool.estimateSmartFee(newConfirmTarget); + } + if (nNewFeeRate.GetFeePerK() == 0) { + nNewFeeRate = CWallet::fallbackFee; + } + + // new fee rate must be at least old rate + minimum relay rate + if (nNewFeeRate.GetFeePerK() < nOldFeeRate.GetFeePerK() + ::minRelayTxFee.GetFeePerK()) { + nNewFeeRate = CFeeRate(nOldFeeRate.GetFeePerK() + ::minRelayTxFee.GetFeePerK()); + } + + nNewFee = nNewFeeRate.GetFee(maxNewTxSize); + } + + // check that fee rate is higher than mempool's minimum fee + // (no point in bumping fee if we know that the new tx won't be accepted to the mempool) + // This may occur if the user set TotalFee or paytxfee too low, if fallbackfee is too low, or, perhaps, + // in a rare situation where the mempool minimum fee increased significantly since the fee estimation just a + // moment earlier. In this case, we report an error to the user, who may use totalFee to make an adjustment. + CFeeRate minMempoolFeeRate = mempool.GetMinFee(GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000); + if (nNewFeeRate.GetFeePerK() < minMempoolFeeRate.GetFeePerK()) { + throw JSONRPCError(RPC_MISC_ERROR, strprintf("New fee rate (%s) is less than the minimum fee rate (%s) to get into the mempool. totalFee value should to be at least %s or settxfee value should be at least %s to add transaction.", FormatMoney(nNewFeeRate.GetFeePerK()), FormatMoney(minMempoolFeeRate.GetFeePerK()), FormatMoney(minMempoolFeeRate.GetFee(maxNewTxSize)), FormatMoney(minMempoolFeeRate.GetFeePerK()))); + } + + // Now modify the output to increase the fee. + // If the output is not large enough to pay the fee, fail. + CAmount nDelta = nNewFee - nOldFee; + assert(nDelta > 0); + CMutableTransaction tx(*(wtx.tx)); + CTxOut* poutput = &(tx.vout[nOutput]); + if (poutput->nValue < nDelta) { + throw JSONRPCError(RPC_MISC_ERROR, "Change output is too small to bump the fee"); + } + + // If the output would become dust, discard it (converting the dust to fee) + poutput->nValue -= nDelta; + if (poutput->nValue <= poutput->GetDustThreshold(::minRelayTxFee)) { + LogPrint("rpc", "Bumping fee and discarding dust output\n"); + nNewFee += poutput->nValue; + tx.vout.erase(tx.vout.begin() + nOutput); + } + + // Mark new tx not replaceable, if requested. + if (!replaceable) { + for (auto& input : tx.vin) { + if (input.nSequence < 0xfffffffe) input.nSequence = 0xfffffffe; + } + } + + // sign the new tx + CTransaction txNewConst(tx); + int nIn = 0; + for (auto& input : tx.vin) { + std::map<uint256, CWalletTx>::const_iterator mi = pwalletMain->mapWallet.find(input.prevout.hash); + assert(mi != pwalletMain->mapWallet.end() && input.prevout.n < mi->second.tx->vout.size()); + const CScript& scriptPubKey = mi->second.tx->vout[input.prevout.n].scriptPubKey; + const CAmount& amount = mi->second.tx->vout[input.prevout.n].nValue; + SignatureData sigdata; + if (!ProduceSignature(TransactionSignatureCreator(pwalletMain, &txNewConst, nIn, amount, SIGHASH_ALL), scriptPubKey, sigdata)) { + throw JSONRPCError(RPC_WALLET_ERROR, "Can't sign transaction."); + } + UpdateTransaction(tx, nIn, sigdata); + nIn++; + } + + // commit/broadcast the tx + CReserveKey reservekey(pwalletMain); + CWalletTx wtxBumped(pwalletMain, MakeTransactionRef(std::move(tx))); + wtxBumped.mapValue["replaces_txid"] = hash.ToString(); + CValidationState state; + if (!pwalletMain->CommitTransaction(wtxBumped, reservekey, g_connman.get(), state) || !state.IsValid()) { + throw JSONRPCError(RPC_WALLET_ERROR, strprintf("Error: The transaction was rejected! Reason given: %s", state.GetRejectReason())); + } + + // mark the original tx as bumped + if (!pwalletMain->MarkReplaced(wtx.GetHash(), wtxBumped.GetHash())) { + // TODO: see if JSON-RPC has a standard way of returning a response + // along with an exception. It would be good to return information about + // wtxBumped to the caller even if marking the original transaction + // replaced does not succeed for some reason. + throw JSONRPCError(RPC_WALLET_ERROR, "Error: Created new bumpfee transaction but could not mark the original transaction as replaced."); + } + + UniValue result(UniValue::VOBJ); + result.push_back(Pair("txid", wtxBumped.GetHash().GetHex())); + result.push_back(Pair("oldfee", ValueFromAmount(nOldFee))); + result.push_back(Pair("fee", ValueFromAmount(nNewFee))); + + return result; +} + extern UniValue dumpprivkey(const JSONRPCRequest& request); // in rpcdump.cpp extern UniValue importprivkey(const JSONRPCRequest& request); extern UniValue importaddress(const JSONRPCRequest& request); @@ -2614,6 +2871,7 @@ static const CRPCCommand commands[] = { "wallet", "addmultisigaddress", &addmultisigaddress, true, {"nrequired","keys","account"} }, { "wallet", "addwitnessaddress", &addwitnessaddress, true, {"address"} }, { "wallet", "backupwallet", &backupwallet, true, {"destination"} }, + { "wallet", "bumpfee", &bumpfee, true, {"txid", "options"} }, { "wallet", "dumpprivkey", &dumpprivkey, true, {"address"} }, { "wallet", "dumpwallet", &dumpwallet, true, {"filename"} }, { "wallet", "encryptwallet", &encryptwallet, true, {"passphrase"} }, diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index be5d692c92..c1e1f2d7ea 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -411,6 +411,13 @@ set<uint256> CWallet::GetConflicts(const uint256& txid) const return result; } +bool CWallet::HasWalletSpend(const uint256& txid) const +{ + AssertLockHeld(cs_wallet); + auto iter = mapTxSpends.lower_bound(COutPoint(txid, 0)); + return (iter != mapTxSpends.end() && iter->first.hash == txid); +} + void CWallet::Flush(bool shutdown) { bitdb.Flush(shutdown); @@ -826,6 +833,35 @@ void CWallet::MarkDirty() } } +bool CWallet::MarkReplaced(const uint256& originalHash, const uint256& newHash) +{ + LOCK(cs_wallet); + + auto mi = mapWallet.find(originalHash); + + // There is a bug if MarkReplaced is not called on an existing wallet transaction. + assert(mi != mapWallet.end()); + + CWalletTx& wtx = (*mi).second; + + // Ensure for now that we're not overwriting data + assert(wtx.mapValue.count("replaced_by_txid") == 0); + + wtx.mapValue["replaced_by_txid"] = newHash.ToString(); + + CWalletDB walletdb(strWalletFile, "r+"); + + bool success = true; + if (!walletdb.WriteTx(wtx)) { + LogPrintf("%s: Updating walletdb tx %s failed", __func__, wtx.GetHash().ToString()); + success = false; + } + + NotifyTransactionChanged(this, originalHash, CT_UPDATED); + + return success; +} + bool CWallet::AddToWallet(const CWalletTx& wtxIn, bool fFlushOnClose) { LOCK(cs_wallet); @@ -1981,6 +2017,37 @@ void CWallet::AvailableCoins(vector<COutput>& vCoins, bool fOnlyConfirmed, const if (nDepth == 0 && !pcoin->InMempool()) continue; + // We should not consider coins from transactions that are replacing + // other transactions. + // + // Example: There is a transaction A which is replaced by bumpfee + // transaction B. In this case, we want to prevent creation of + // a transaction B' which spends an output of B. + // + // Reason: If transaction A were initially confirmed, transactions B + // and B' would no longer be valid, so the user would have to create + // a new transaction C to replace B'. However, in the case of a + // one-block reorg, transactions B' and C might BOTH be accepted, + // when the user only wanted one of them. Specifically, there could + // be a 1-block reorg away from the chain where transactions A and C + // were accepted to another chain where B, B', and C were all + // accepted. + if (nDepth == 0 && fOnlyConfirmed && pcoin->mapValue.count("replaces_txid")) { + continue; + } + + // Similarly, we should not consider coins from transactions that + // have been replaced. In the example above, we would want to prevent + // creation of a transaction A' spending an output of A, because if + // transaction B were initially confirmed, conflicting with A and + // A', we wouldn't want to the user to create a transaction D + // intending to replace A', but potentially resulting in a scenario + // where A, A', and D could all be accepted (instead of just B and + // D, or just A and A' like the user would want). + if (nDepth == 0 && fOnlyConfirmed && pcoin->mapValue.count("replaced_by_txid")) { + continue; + } + for (unsigned int i = 0; i < pcoin->tx->vout.size(); i++) { isminetype mine = IsMine(pcoin->tx->vout[i]); if (!(IsSpent(wtxid, i)) && mine != ISMINE_NO && diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h index 8a587f4ed0..50c5025c24 100644 --- a/src/wallet/wallet.h +++ b/src/wallet/wallet.h @@ -891,6 +891,9 @@ public: //! Get wallet transactions that conflict with given transaction (spend same outputs) std::set<uint256> GetConflicts(const uint256& txid) const; + //! Check if a given transaction has any of its outputs spent by another transaction in the wallet + bool HasWalletSpend(const uint256& txid) const; + //! Flush wallet (bitdb flush) void Flush(bool shutdown=false); @@ -927,6 +930,9 @@ public: /* Mark a transaction (and it in-wallet descendants) as abandoned so its inputs may be respent. */ bool AbandonTransaction(const uint256& hashTx); + /** Mark a transaction as replaced by another transaction (e.g., BIP 125). */ + bool MarkReplaced(const uint256& originalHash, const uint256& newHash); + /* Returns the wallets help message */ static std::string GetWalletHelpString(bool showDebug); |