private void parsePaymentRequest(Protos.PaymentRequest request) throws PaymentProtocolException { try { if (request == null) throw new PaymentProtocolException("request cannot be null"); if (request.getPaymentDetailsVersion() != 1) throw new PaymentProtocolException.InvalidVersion( "Version 1 required. Received version " + request.getPaymentDetailsVersion()); paymentRequest = request; if (!request.hasSerializedPaymentDetails()) throw new PaymentProtocolException("No PaymentDetails"); paymentDetails = Protos.PaymentDetails.newBuilder() .mergeFrom(request.getSerializedPaymentDetails()) .build(); if (paymentDetails == null) throw new PaymentProtocolException("Invalid PaymentDetails"); if (!paymentDetails.hasNetwork()) params = MainNetParams.get(); else params = NetworkParameters.fromPmtProtocolID(paymentDetails.getNetwork()); if (params == null) throw new PaymentProtocolException.InvalidNetwork( "Invalid network " + paymentDetails.getNetwork()); if (paymentDetails.getOutputsCount() < 1) throw new PaymentProtocolException.InvalidOutputs("No outputs"); for (Protos.Output output : paymentDetails.getOutputsList()) { if (output.hasAmount()) totalValue = totalValue.add(Coin.valueOf(output.getAmount())); } // This won't ever happen in practice. It would only happen if the user provided outputs // that are obviously invalid. Still, we don't want to silently overflow. if (params.hasMaxMoney() && totalValue.compareTo(params.getMaxMoney()) > 0) throw new PaymentProtocolException.InvalidOutputs("The outputs are way too big."); } catch (InvalidProtocolBufferException e) { throw new PaymentProtocolException(e); } }
/** * Creates the initial multisig contract and incomplete refund transaction which can be requested * at the appropriate time using {@link PaymentChannelClientState#getIncompleteRefundTransaction} * and {@link PaymentChannelClientState#getMultisigContract()}. The way the contract is crafted * can be adjusted by overriding {@link * PaymentChannelClientState#editContractSendRequest(com.google.bitcoin.core.Wallet.SendRequest)}. * By default unconfirmed coins are allowed to be used, as for micropayments the risk should be * relatively low. * * @throws ValueOutOfRangeException if the value being used is too small to be accepted by the * network * @throws InsufficientMoneyException if the wallet doesn't contain enough balance to initiate */ public synchronized void initiate() throws ValueOutOfRangeException, InsufficientMoneyException { final NetworkParameters params = wallet.getParams(); Transaction template = new Transaction(params); // We always place the client key before the server key because, if either side wants some // privacy, they can // use a fresh key for the the multisig contract and nowhere else List<ECKey> keys = Lists.newArrayList(myKey, serverMultisigKey); // There is also probably a change output, but we don't bother shuffling them as it's obvious // from the // format which one is the change. If we start obfuscating the change output better in future // this may // be worth revisiting. TransactionOutput multisigOutput = template.addOutput(totalValue, ScriptBuilder.createMultiSigOutputScript(2, keys)); if (multisigOutput.getMinNonDustValue().compareTo(totalValue) > 0) throw new ValueOutOfRangeException("totalValue too small to use"); Wallet.SendRequest req = Wallet.SendRequest.forTx(template); req.coinSelector = AllowUnconfirmedCoinSelector.get(); editContractSendRequest(req); req.shuffleOutputs = false; // TODO: Fix things so shuffling is usable. wallet.completeTx(req); Coin multisigFee = req.tx.getFee(); multisigContract = req.tx; // Build a refund transaction that protects us in the case of a bad server that's just trying to // cause havoc // by locking up peoples money (perhaps as a precursor to a ransom attempt). We time lock it so // the server // has an assurance that we cannot take back our money by claiming a refund before the channel // closes - this // relies on the fact that since Bitcoin 0.8 time locked transactions are non-final. This will // need to change // in future as it breaks the intended design of timelocking/tx replacement, but for now it // simplifies this // specific protocol somewhat. refundTx = new Transaction(params); refundTx .addInput(multisigOutput) .setSequenceNumber(0); // Allow replacement when it's eventually reactivated. refundTx.setLockTime(expiryTime); if (totalValue.compareTo(Coin.CENT) < 0) { // Must pay min fee. final Coin valueAfterFee = totalValue.subtract(Transaction.REFERENCE_DEFAULT_MIN_TX_FEE); if (Transaction.MIN_NONDUST_OUTPUT.compareTo(valueAfterFee) > 0) throw new ValueOutOfRangeException("totalValue too small to use"); refundTx.addOutput(valueAfterFee, myKey.toAddress(params)); refundFees = multisigFee.add(Transaction.REFERENCE_DEFAULT_MIN_TX_FEE); } else { refundTx.addOutput(totalValue, myKey.toAddress(params)); refundFees = multisigFee; } refundTx.getConfidence().setSource(TransactionConfidence.Source.SELF); log.info( "initiated channel with multi-sig contract {}, refund {}", multisigContract.getHashAsString(), refundTx.getHashAsString()); state = State.INITIATED; // Client should now call getIncompleteRefundTransaction() and send it to the server. }
/** * Returns the outstanding amount of money sent back to us for all channels to this server added * together. */ public Coin getBalanceForServer(Sha256Hash id) { Coin balance = Coin.ZERO; lock.lock(); try { Set<StoredClientChannel> setChannels = mapChannels.get(id); for (StoredClientChannel channel : setChannels) { synchronized (channel) { if (channel.close != null) continue; balance = balance.add(channel.valueToMe); } } return balance; } finally { lock.unlock(); } }
@Override public CoinSelection select(Coin target, List<TransactionOutput> candidates) { try { LinkedList<TransactionOutput> gathered = Lists.newLinkedList(); Coin valueGathered = Coin.ZERO; for (TransactionOutput output : candidates) { if (ignorePending && !isConfirmed(output)) continue; // Find the key that controls output, assuming it's a regular pay-to-pubkey or // pay-to-address output. // We ignore any other kind of exotic output on the assumption we can't spend it ourselves. final Script scriptPubKey = output.getScriptPubKey(); ECKey controllingKey; if (scriptPubKey.isSentToRawPubKey()) { controllingKey = wallet.findKeyFromPubKey(scriptPubKey.getPubKey()); } else if (scriptPubKey.isSentToAddress()) { controllingKey = wallet.findKeyFromPubHash(scriptPubKey.getPubKeyHash()); } else { log.info("Skipping tx output {} because it's not of simple form.", output); continue; } checkNotNull( controllingKey, "Coin selector given output as candidate for which we lack the key"); if (controllingKey.getCreationTimeSeconds() >= unixTimeSeconds) continue; // It's older than the cutoff time so select. valueGathered = valueGathered.add(output.getValue()); gathered.push(output); if (gathered.size() >= MAX_SIMULTANEOUS_INPUTS) { log.warn( "Reached {} inputs, going further would yield a tx that is too large, stopping here.", gathered.size()); break; } } return new CoinSelection(valueGathered, gathered); } catch (ScriptException e) { throw new RuntimeException( e); // We should never have problems understanding scripts in our wallet. } }
@Override /** Used during reorgs to connect a block previously on a fork */ protected synchronized TransactionOutputChanges connectTransactions(StoredBlock newBlock) throws VerificationException, BlockStoreException, PrunedException { checkState(lock.isHeldByCurrentThread()); if (!params.passesCheckpoint(newBlock.getHeight(), newBlock.getHeader().getHash())) throw new VerificationException("Block failed checkpoint lockin at " + newBlock.getHeight()); blockStore.beginDatabaseBatchWrite(); StoredUndoableBlock block = blockStore.getUndoBlock(newBlock.getHeader().getHash()); if (block == null) { // We're trying to re-org too deep and the data needed has been deleted. blockStore.abortDatabaseBatchWrite(); throw new PrunedException(newBlock.getHeader().getHash()); } TransactionOutputChanges txOutChanges; try { List<Transaction> transactions = block.getTransactions(); if (transactions != null) { LinkedList<StoredTransactionOutput> txOutsSpent = new LinkedList<StoredTransactionOutput>(); LinkedList<StoredTransactionOutput> txOutsCreated = new LinkedList<StoredTransactionOutput>(); long sigOps = 0; final boolean enforcePayToScriptHash = newBlock.getHeader().getTimeSeconds() >= NetworkParameters.BIP16_ENFORCE_TIME; if (!params.isCheckpoint(newBlock.getHeight())) { for (Transaction tx : transactions) { Sha256Hash hash = tx.getHash(); if (blockStore.hasUnspentOutputs(hash, tx.getOutputs().size())) throw new VerificationException("Block failed BIP30 test!"); } } Coin totalFees = Coin.ZERO; Coin coinbaseValue = null; if (scriptVerificationExecutor.isShutdown()) scriptVerificationExecutor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()); List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<Future<VerificationException>>(transactions.size()); for (final Transaction tx : transactions) { boolean isCoinBase = tx.isCoinBase(); Coin valueIn = Coin.ZERO; Coin valueOut = Coin.ZERO; final List<Script> prevOutScripts = new LinkedList<Script>(); if (!isCoinBase) { for (int index = 0; index < tx.getInputs().size(); index++) { final TransactionInput in = tx.getInputs().get(index); final StoredTransactionOutput prevOut = blockStore.getTransactionOutput( in.getOutpoint().getHash(), in.getOutpoint().getIndex()); if (prevOut == null) throw new VerificationException( "Attempted spend of a non-existent or already spent output!"); if (newBlock.getHeight() - prevOut.getHeight() < params.getSpendableCoinbaseDepth()) throw new VerificationException( "Tried to spend coinbase at depth " + (newBlock.getHeight() - prevOut.getHeight())); valueIn = valueIn.add(prevOut.getValue()); if (enforcePayToScriptHash) { Script script = new Script(prevOut.getScriptBytes()); if (script.isPayToScriptHash()) sigOps += Script.getP2SHSigOpCount(in.getScriptBytes()); if (sigOps > Block.MAX_BLOCK_SIGOPS) throw new VerificationException("Too many P2SH SigOps in block"); } prevOutScripts.add(new Script(prevOut.getScriptBytes())); blockStore.removeUnspentTransactionOutput(prevOut); txOutsSpent.add(prevOut); } } Sha256Hash hash = tx.getHash(); for (TransactionOutput out : tx.getOutputs()) { valueOut = valueOut.add(out.getValue()); StoredTransactionOutput newOut = new StoredTransactionOutput( hash, out.getIndex(), out.getValue(), newBlock.getHeight(), isCoinBase, out.getScriptBytes()); blockStore.addUnspentTransactionOutput(newOut); txOutsCreated.add(newOut); } // All values were already checked for being non-negative (as it is verified in // Transaction.verify()) // but we check again here just for defence in depth. Transactions with zero output value // are OK. if (valueOut.signum() < 0 || valueOut.compareTo(NetworkParameters.MAX_MONEY) > 0) throw new VerificationException("Transaction output value out of range"); if (isCoinBase) { coinbaseValue = valueOut; } else { if (valueIn.compareTo(valueOut) < 0 || valueIn.compareTo(NetworkParameters.MAX_MONEY) > 0) throw new VerificationException("Transaction input value out of range"); totalFees = totalFees.add(valueIn.subtract(valueOut)); } if (!isCoinBase) { // Because correctlySpends modifies transactions, this must come after we are done with // tx FutureTask<VerificationException> future = new FutureTask<VerificationException>( new Verifier(tx, prevOutScripts, enforcePayToScriptHash)); scriptVerificationExecutor.execute(future); listScriptVerificationResults.add(future); } } if (totalFees.compareTo(NetworkParameters.MAX_MONEY) > 0 || newBlock .getHeader() .getBlockInflation(newBlock.getHeight()) .add(totalFees) .compareTo(coinbaseValue) < 0) throw new VerificationException("Transaction fees out of range"); txOutChanges = new TransactionOutputChanges(txOutsCreated, txOutsSpent); for (Future<VerificationException> future : listScriptVerificationResults) { VerificationException e; try { e = future.get(); } catch (InterruptedException thrownE) { throw new RuntimeException(thrownE); // Shouldn't happen } catch (ExecutionException thrownE) { log.error("Script.correctlySpends threw a non-normal exception: " + thrownE.getCause()); throw new VerificationException( "Bug in Script.correctlySpends, likely script malformed in some new and interesting way.", thrownE); } if (e != null) throw e; } } else { txOutChanges = block.getTxOutChanges(); if (!params.isCheckpoint(newBlock.getHeight())) for (StoredTransactionOutput out : txOutChanges.txOutsCreated) { Sha256Hash hash = out.getHash(); if (blockStore.getTransactionOutput(hash, out.getIndex()) != null) throw new VerificationException("Block failed BIP30 test!"); } for (StoredTransactionOutput out : txOutChanges.txOutsCreated) blockStore.addUnspentTransactionOutput(out); for (StoredTransactionOutput out : txOutChanges.txOutsSpent) blockStore.removeUnspentTransactionOutput(out); } } catch (VerificationException e) { scriptVerificationExecutor.shutdownNow(); blockStore.abortDatabaseBatchWrite(); throw e; } catch (BlockStoreException e) { scriptVerificationExecutor.shutdownNow(); blockStore.abortDatabaseBatchWrite(); throw e; } return txOutChanges; }
@Override protected TransactionOutputChanges connectTransactions(int height, Block block) throws VerificationException, BlockStoreException { checkState(lock.isHeldByCurrentThread()); if (block.transactions == null) throw new RuntimeException( "connectTransactions called with Block that didn't have transactions!"); if (!params.passesCheckpoint(height, block.getHash())) throw new VerificationException("Block failed checkpoint lockin at " + height); blockStore.beginDatabaseBatchWrite(); LinkedList<StoredTransactionOutput> txOutsSpent = new LinkedList<StoredTransactionOutput>(); LinkedList<StoredTransactionOutput> txOutsCreated = new LinkedList<StoredTransactionOutput>(); long sigOps = 0; final boolean enforcePayToScriptHash = block.getTimeSeconds() >= NetworkParameters.BIP16_ENFORCE_TIME; if (scriptVerificationExecutor.isShutdown()) scriptVerificationExecutor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()); List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<Future<VerificationException>>(block.transactions.size()); try { if (!params.isCheckpoint(height)) { // BIP30 violator blocks are ones that contain a duplicated transaction. They are all in the // checkpoints list and we therefore only check non-checkpoints for duplicated transactions // here. See the // BIP30 document for more details on this: // https://github.com/bitcoin/bips/blob/master/bip-0030.mediawiki for (Transaction tx : block.transactions) { Sha256Hash hash = tx.getHash(); // If we already have unspent outputs for this hash, we saw the tx already. Either the // block is // being added twice (bug) or the block is a BIP30 violator. if (blockStore.hasUnspentOutputs(hash, tx.getOutputs().size())) throw new VerificationException("Block failed BIP30 test!"); if (enforcePayToScriptHash) // We already check non-BIP16 sigops in // Block.verifyTransactions(true) sigOps += tx.getSigOpCount(); } } Coin totalFees = Coin.ZERO; Coin coinbaseValue = null; for (final Transaction tx : block.transactions) { boolean isCoinBase = tx.isCoinBase(); Coin valueIn = Coin.ZERO; Coin valueOut = Coin.ZERO; final List<Script> prevOutScripts = new LinkedList<Script>(); if (!isCoinBase) { // For each input of the transaction remove the corresponding output from the set of // unspent // outputs. for (int index = 0; index < tx.getInputs().size(); index++) { TransactionInput in = tx.getInputs().get(index); StoredTransactionOutput prevOut = blockStore.getTransactionOutput( in.getOutpoint().getHash(), in.getOutpoint().getIndex()); if (prevOut == null) throw new VerificationException( "Attempted to spend a non-existent or already spent output!"); // Coinbases can't be spent until they mature, to avoid re-orgs destroying entire // transaction // chains. The assumption is there will ~never be re-orgs deeper than the spendable // coinbase // chain depth. if (height - prevOut.getHeight() < params.getSpendableCoinbaseDepth()) throw new VerificationException( "Tried to spend coinbase at depth " + (height - prevOut.getHeight())); // TODO: Check we're not spending the genesis transaction here. Satoshis code won't // allow it. valueIn = valueIn.add(prevOut.getValue()); if (enforcePayToScriptHash) { if (new Script(prevOut.getScriptBytes()).isPayToScriptHash()) sigOps += Script.getP2SHSigOpCount(in.getScriptBytes()); if (sigOps > Block.MAX_BLOCK_SIGOPS) throw new VerificationException("Too many P2SH SigOps in block"); } prevOutScripts.add(new Script(prevOut.getScriptBytes())); // in.getScriptSig().correctlySpends(tx, index, new Script(params, // prevOut.getScriptBytes(), 0, prevOut.getScriptBytes().length)); blockStore.removeUnspentTransactionOutput(prevOut); txOutsSpent.add(prevOut); } } Sha256Hash hash = tx.getHash(); for (TransactionOutput out : tx.getOutputs()) { valueOut = valueOut.add(out.getValue()); // For each output, add it to the set of unspent outputs so it can be consumed in future. StoredTransactionOutput newOut = new StoredTransactionOutput( hash, out.getIndex(), out.getValue(), height, isCoinBase, out.getScriptBytes()); blockStore.addUnspentTransactionOutput(newOut); txOutsCreated.add(newOut); } // All values were already checked for being non-negative (as it is verified in // Transaction.verify()) // but we check again here just for defence in depth. Transactions with zero output value // are OK. if (valueOut.signum() < 0 || valueOut.compareTo(NetworkParameters.MAX_MONEY) > 0) throw new VerificationException("Transaction output value out of range"); if (isCoinBase) { coinbaseValue = valueOut; } else { if (valueIn.compareTo(valueOut) < 0 || valueIn.compareTo(NetworkParameters.MAX_MONEY) > 0) throw new VerificationException("Transaction input value out of range"); totalFees = totalFees.add(valueIn.subtract(valueOut)); } if (!isCoinBase && runScripts) { // Because correctlySpends modifies transactions, this must come after we are done with tx FutureTask<VerificationException> future = new FutureTask<VerificationException>( new Verifier(tx, prevOutScripts, enforcePayToScriptHash)); scriptVerificationExecutor.execute(future); listScriptVerificationResults.add(future); } } if (totalFees.compareTo(NetworkParameters.MAX_MONEY) > 0 || block.getBlockInflation(height).add(totalFees).compareTo(coinbaseValue) < 0) throw new VerificationException("Transaction fees out of range"); for (Future<VerificationException> future : listScriptVerificationResults) { VerificationException e; try { e = future.get(); } catch (InterruptedException thrownE) { throw new RuntimeException(thrownE); // Shouldn't happen } catch (ExecutionException thrownE) { log.error("Script.correctlySpends threw a non-normal exception: " + thrownE.getCause()); throw new VerificationException( "Bug in Script.correctlySpends, likely script malformed in some new and interesting way.", thrownE); } if (e != null) throw e; } } catch (VerificationException e) { scriptVerificationExecutor.shutdownNow(); blockStore.abortDatabaseBatchWrite(); throw e; } catch (BlockStoreException e) { scriptVerificationExecutor.shutdownNow(); blockStore.abortDatabaseBatchWrite(); throw e; } return new TransactionOutputChanges(txOutsCreated, txOutsSpent); }