@Test
public void fourPeers() throws Exception {
InboundMessageQueuer[] channels = {
connectPeer(1), connectPeer(2), connectPeer(3), connectPeer(4)
};
Transaction tx = new Transaction(params);
TransactionBroadcast broadcast = new TransactionBroadcast(peerGroup, tx);
ListenableFuture<Transaction> future = broadcast.broadcast();
assertFalse(future.isDone());
// We expect two peers to receive a tx message, and at least one of the others must announce for
// the future to
// complete successfully.
Message[] messages = {
(Message) outbound(channels[0]),
(Message) outbound(channels[1]),
(Message) outbound(channels[2]),
(Message) outbound(channels[3])
};
// 0 and 3 are randomly selected to receive the broadcast.
assertEquals(tx, messages[0]);
assertEquals(tx, messages[3]);
assertNull(messages[1]);
assertNull(messages[2]);
Threading.waitForUserCode();
assertFalse(future.isDone());
inbound(channels[1], InventoryMessage.with(tx));
pingAndWait(channels[1]);
Threading.waitForUserCode();
assertTrue(future.isDone());
}
/**
* An AbstractBlockChain holds a series of {@link Block} objects, links them together, and knows how
* to verify that the chain follows the rules of the {@link NetworkParameters} for this chain.
*
* <p>It can be connected to a {@link Wallet}, and also {@link BlockChainListener}s that can receive
* transactions and notifications of re-organizations.
*
* <p>An AbstractBlockChain implementation must be connected to a {@link BlockStore} implementation.
* The chain object by itself doesn't store any data, that's delegated to the store. Which store you
* use is a decision best made by reading the getting started guide, but briefly, fully validating
* block chains need fully validating stores. In the lightweight SPV mode, a {@link
* org.bitcoinj.store.SPVBlockStore} is the right choice.
*
* <p>This class implements an abstract class which makes it simple to create a BlockChain that
* does/doesn't do full verification. It verifies headers and is implements most of what is required
* to implement SPV mode, but also provides callback hooks which can be used to do full
* verification.
*
* <p>There are two subclasses of AbstractBlockChain that are useful: {@link BlockChain}, which is
* the simplest class and implements <i>simplified payment verification</i>. This is a lightweight
* and efficient mode that does not verify the contents of blocks, just their headers. A {@link
* FullPrunedBlockChain} paired with a {@link org.bitcoinj.store.H2FullPrunedBlockStore} implements
* full verification, which is equivalent to the original Satoshi client. To learn more about the
* alternative security models, please consult the articles on the website. <b>Theory</b>
*
* <p>The 'chain' is actually a tree although in normal operation it operates mostly as a list of
* {@link Block}s. When multiple new head blocks are found simultaneously, there are multiple
* stories of the economy competing to become the one true consensus. This can happen naturally when
* two miners solve a block within a few seconds of each other, or it can happen when the chain is
* under attack.
*
* <p>A reference to the head block of the best known chain is stored. If you can reach the genesis
* block by repeatedly walking through the prevBlock pointers, then we say this is a full chain. If
* you cannot reach the genesis block we say it is an orphan chain. Orphan chains can occur when
* blocks are solved and received during the initial block chain download, or if we connect to a
* peer that doesn't send us blocks in order.
*
* <p>A reorganize occurs when the blocks that make up the best known chain changes. Note that
* simply adding a new block to the top of the best chain isn't as reorganize, but that a reorganize
* is always triggered by adding a new block that connects to some other (non best head) block. By
* "best" we mean the chain representing the largest amount of work done.
*
* <p>Every so often the block chain passes a difficulty transition point. At that time, all the
* blocks in the last 2016 blocks are examined and a new difficulty target is calculated from them.
*/
public abstract class AbstractBlockChain {
private static final Logger log = LoggerFactory.getLogger(AbstractBlockChain.class);
protected final ReentrantLock lock = Threading.lock("blockchain");
/** Keeps a map of block hashes to StoredBlocks. */
private final BlockStore blockStore;
/**
* Tracks the top of the best known chain.
*
* <p>Following this one down to the genesis block produces the story of the economy from the
* creation of Bitcoin until the present day. The chain head can change if a new set of blocks is
* received that results in a chain of greater work than the one obtained by following this one
* down. In that case a reorganize is triggered, potentially invalidating transactions in our
* wallet.
*/
protected StoredBlock chainHead;
// TODO: Scrap this and use a proper read/write for all of the block chain objects.
// The chainHead field is read/written synchronized with this object rather than BlockChain.
// However writing is
// also guaranteed to happen whilst BlockChain is synchronized (see setChainHead). The goal of
// this is to let
// clients quickly access the chain head even whilst the block chain is downloading and thus the
// BlockChain is
// locked most of the time.
private final Object chainHeadLock = new Object();
protected final NetworkParameters params;
private final CopyOnWriteArrayList<ListenerRegistration<BlockChainListener>> listeners;
// Holds a block header and, optionally, a list of tx hashes or block's transactions
class OrphanBlock {
final Block block;
final List<Sha256Hash> filteredTxHashes;
final Map<Sha256Hash, Transaction> filteredTxn;
OrphanBlock(
Block block,
@Nullable List<Sha256Hash> filteredTxHashes,
@Nullable Map<Sha256Hash, Transaction> filteredTxn) {
final boolean filtered = filteredTxHashes != null && filteredTxn != null;
Preconditions.checkArgument(
(block.transactions == null && filtered) || (block.transactions != null && !filtered));
if (!shouldVerifyTransactions()) this.block = block.cloneAsHeader();
else this.block = block;
this.filteredTxHashes = filteredTxHashes;
this.filteredTxn = filteredTxn;
}
}
// Holds blocks that we have received but can't plug into the chain yet, eg because they were
// created whilst we
// were downloading the block chain.
private final LinkedHashMap<Sha256Hash, OrphanBlock> orphanBlocks =
new LinkedHashMap<Sha256Hash, OrphanBlock>();
/** False positive estimation uses a double exponential moving average. */
public static final double FP_ESTIMATOR_ALPHA = 0.0001;
/** False positive estimation uses a double exponential moving average. */
public static final double FP_ESTIMATOR_BETA = 0.01;
private double falsePositiveRate;
private double falsePositiveTrend;
private double previousFalsePositiveRate;
/** See {@link #AbstractBlockChain(Context, List, BlockStore)} */
public AbstractBlockChain(
NetworkParameters params, List<BlockChainListener> listeners, BlockStore blockStore)
throws BlockStoreException {
this(Context.getOrCreate(params), listeners, blockStore);
}
/** Constructs a BlockChain connected to the given list of listeners (eg, wallets) and a store. */
public AbstractBlockChain(
Context context, List<BlockChainListener> listeners, BlockStore blockStore)
throws BlockStoreException {
this.blockStore = blockStore;
chainHead = blockStore.getChainHead();
log.info("chain head is at height {}:\n{}", chainHead.getHeight(), chainHead.getHeader());
this.params = context.getParams();
this.listeners = new CopyOnWriteArrayList<ListenerRegistration<BlockChainListener>>();
for (BlockChainListener l : listeners) addListener(l, Threading.SAME_THREAD);
}
/**
* Add a wallet to the BlockChain. Note that the wallet will be unaffected by any blocks received
* while it was not part of this BlockChain. This method is useful if the wallet has just been
* created, and its keys have never been in use, or if the wallet has been loaded along with the
* BlockChain. Note that adding multiple wallets is not well tested!
*/
public void addWallet(Wallet wallet) {
addListener(wallet, Threading.SAME_THREAD);
int walletHeight = wallet.getLastBlockSeenHeight();
int chainHeight = getBestChainHeight();
if (walletHeight != chainHeight) {
log.warn("Wallet/chain height mismatch: {} vs {}", walletHeight, chainHeight);
log.warn(
"Hashes: {} vs {}", wallet.getLastBlockSeenHash(), getChainHead().getHeader().getHash());
// This special case happens when the VM crashes because of a transaction received. It causes
// the updated
// block store to persist, but not the wallet. In order to fix the issue, we roll back the
// block store to
// the wallet height to make it look like as if the block has never been received.
if (walletHeight < chainHeight && walletHeight > 0) {
try {
rollbackBlockStore(walletHeight);
log.info("Rolled back block store to height {}.", walletHeight);
} catch (BlockStoreException x) {
log.warn(
"Rollback of block store failed, continuing with mismatched heights. This can happen due to a replay.");
}
}
}
}
/** Removes a wallet from the chain. */
public void removeWallet(Wallet wallet) {
removeListener(wallet);
}
/** Adds a generic {@link BlockChainListener} listener to the chain. */
public void addListener(BlockChainListener listener) {
addListener(listener, Threading.USER_THREAD);
}
/** Adds a generic {@link BlockChainListener} listener to the chain. */
public void addListener(BlockChainListener listener, Executor executor) {
listeners.add(new ListenerRegistration<BlockChainListener>(listener, executor));
}
/** Removes the given {@link BlockChainListener} from the chain. */
public void removeListener(BlockChainListener listener) {
ListenerRegistration.removeFromList(listener, listeners);
}
/**
* Returns the {@link BlockStore} the chain was constructed with. You can use this to iterate over
* the chain.
*/
public BlockStore getBlockStore() {
return blockStore;
}
/**
* Adds/updates the given {@link Block} with the block store. This version is used when the
* transactions have not been verified.
*
* @param storedPrev The {@link StoredBlock} which immediately precedes block.
* @param block The {@link Block} to add/update.
* @return the newly created {@link StoredBlock}
*/
protected abstract StoredBlock addToBlockStore(StoredBlock storedPrev, Block block)
throws BlockStoreException, VerificationException;
/**
* Adds/updates the given {@link StoredBlock} with the block store. This version is used when the
* transactions have already been verified to properly spend txOutputChanges.
*
* @param storedPrev The {@link StoredBlock} which immediately precedes block.
* @param header The {@link StoredBlock} to add/update.
* @param txOutputChanges The total sum of all changes made by this block to the set of open
* transaction outputs (from a call to connectTransactions), if in fully verifying mode (null
* otherwise).
* @return the newly created {@link StoredBlock}
*/
protected abstract StoredBlock addToBlockStore(
StoredBlock storedPrev, Block header, @Nullable TransactionOutputChanges txOutputChanges)
throws BlockStoreException, VerificationException;
/**
* Rollback the block store to a given height. This is currently only supported by {@link
* BlockChain} instances.
*
* @throws BlockStoreException if the operation fails or is unsupported.
*/
protected abstract void rollbackBlockStore(int height) throws BlockStoreException;
/**
* Called before setting chain head in memory. Should write the new head to block store and then
* commit any database transactions that were started by
* disconnectTransactions/connectTransactions.
*/
protected abstract void doSetChainHead(StoredBlock chainHead) throws BlockStoreException;
/**
* Called if we (possibly) previously called disconnectTransaction/connectTransactions, but will
* not be calling preSetChainHead as a block failed verification. Can be used to abort database
* transactions that were started by disconnectTransactions/connectTransactions.
*/
protected abstract void notSettingChainHead() throws BlockStoreException;
/**
* For a standard BlockChain, this should return blockStore.get(hash), for a FullPrunedBlockChain
* blockStore.getOnceUndoableStoredBlock(hash)
*/
protected abstract StoredBlock getStoredBlockInCurrentScope(Sha256Hash hash)
throws BlockStoreException;
/**
* Processes a received block and tries to add it to the chain. If there's something wrong with
* the block an exception is thrown. If the block is OK but cannot be connected to the chain at
* this time, returns false. If the block can be connected to the chain, returns true. Accessing
* block's transactions in another thread while this method runs may result in undefined behavior.
*/
public boolean add(Block block) throws VerificationException, PrunedException {
try {
return add(block, true, null, null);
} catch (BlockStoreException e) {
// TODO: Figure out a better way to propagate this exception to the user.
throw new RuntimeException(e);
} catch (VerificationException e) {
try {
notSettingChainHead();
} catch (BlockStoreException e1) {
throw new RuntimeException(e1);
}
throw new VerificationException(
"Could not verify block " + block.getHashAsString() + "\n" + block.toString(), e);
}
}
/**
* Processes a received block and tries to add it to the chain. If there's something wrong with
* the block an exception is thrown. If the block is OK but cannot be connected to the chain at
* this time, returns false. If the block can be connected to the chain, returns true.
*/
public boolean add(FilteredBlock block) throws VerificationException, PrunedException {
try {
// The block has a list of hashes of transactions that matched the Bloom filter, and a list of
// associated
// Transaction objects. There may be fewer Transaction objects than hashes, this is expected.
// It can happen
// in the case where we were already around to witness the initial broadcast, so we downloaded
// the
// transaction and sent it to the wallet before this point (the wallet may have thrown it away
// if it was
// a false positive, as expected in any Bloom filtering scheme). The filteredTxn list here
// will usually
// only be full of data when we are catching up to the head of the chain and thus haven't
// witnessed any
// of the transactions.
return add(
block.getBlockHeader(),
true,
block.getTransactionHashes(),
block.getAssociatedTransactions());
} catch (BlockStoreException e) {
// TODO: Figure out a better way to propagate this exception to the user.
throw new RuntimeException(e);
} catch (VerificationException e) {
try {
notSettingChainHead();
} catch (BlockStoreException e1) {
throw new RuntimeException(e1);
}
throw new VerificationException(
"Could not verify block " + block.getHash().toString() + "\n" + block.toString(), e);
}
}
/**
* Whether or not we are maintaining a set of unspent outputs and are verifying all transactions.
* Also indicates that all calls to add() should provide a block containing transactions
*/
protected abstract boolean shouldVerifyTransactions();
/**
* Connect each transaction in block.transactions, verifying them as we go and removing spent
* outputs If an error is encountered in a transaction, no changes should be made to the
* underlying BlockStore. and a VerificationException should be thrown. Only called
* if(shouldVerifyTransactions())
*
* @throws VerificationException if an attempt was made to spend an already-spent output, or if a
* transaction incorrectly solved an output script.
* @throws BlockStoreException if the block store had an underlying error.
* @return The full set of all changes made to the set of open transaction outputs.
*/
protected abstract TransactionOutputChanges connectTransactions(int height, Block block)
throws VerificationException, BlockStoreException;
/**
* Load newBlock from BlockStore and connect its transactions, returning changes to the set of
* unspent transactions. If an error is encountered in a transaction, no changes should be made to
* the underlying BlockStore. Only called if(shouldVerifyTransactions())
*
* @throws PrunedException if newBlock does not exist as a {@link StoredUndoableBlock} in the
* block store.
* @throws VerificationException if an attempt was made to spend an already-spent output, or if a
* transaction incorrectly solved an output script.
* @throws BlockStoreException if the block store had an underlying error or newBlock does not
* exist in the block store at all.
* @return The full set of all changes made to the set of open transaction outputs.
*/
protected abstract TransactionOutputChanges connectTransactions(StoredBlock newBlock)
throws VerificationException, BlockStoreException, PrunedException;
// filteredTxHashList contains all transactions, filteredTxn just a subset
private boolean add(
Block block,
boolean tryConnecting,
@Nullable List<Sha256Hash> filteredTxHashList,
@Nullable Map<Sha256Hash, Transaction> filteredTxn)
throws BlockStoreException, VerificationException, PrunedException {
// TODO: Use read/write locks to ensure that during chain download properties are still low
// latency.
lock.lock();
try {
// Quick check for duplicates to avoid an expensive check further down (in findSplit). This
// can happen a lot
// when connecting orphan transactions due to the dumb brute force algorithm we use.
if (block.equals(getChainHead().getHeader())) {
return true;
}
if (tryConnecting && orphanBlocks.containsKey(block.getHash())) {
return false;
}
// If we want to verify transactions (ie we are running with full blocks), verify that block
// has transactions
if (shouldVerifyTransactions() && block.transactions == null)
throw new VerificationException("Got a block header while running in full-block mode");
// Check for already-seen block, but only for full pruned mode, where the DB is
// more likely able to handle these queries quickly.
if (shouldVerifyTransactions() && blockStore.get(block.getHash()) != null) {
return true;
}
// Does this block contain any transactions we might care about? Check this up front before
// verifying the
// blocks validity so we can skip the merkle root verification if the contents aren't
// interesting. This saves
// a lot of time for big blocks.
boolean contentsImportant = shouldVerifyTransactions();
if (block.transactions != null) {
contentsImportant = contentsImportant || containsRelevantTransactions(block);
}
// Prove the block is internally valid: hash is lower than target, etc. This only checks the
// block contents
// if there is a tx sending or receiving coins using an address in one of our wallets. And
// those transactions
// are only lightly verified: presence in a valid connecting block is taken as proof of
// validity. See the
// article here for more details: http://code.google.com/p/bitcoinj/wiki/SecurityModel
try {
block.verifyHeader();
if (contentsImportant) block.verifyTransactions();
} catch (VerificationException e) {
log.error("Failed to verify block: ", e);
log.error(block.getHashAsString());
throw e;
}
// Try linking it to a place in the currently known blocks.
StoredBlock storedPrev = getStoredBlockInCurrentScope(block.getPrevBlockHash());
if (storedPrev == null) {
// We can't find the previous block. Probably we are still in the process of downloading the
// chain and a
// block was solved whilst we were doing it. We put it to one side and try to connect it
// later when we
// have more blocks.
checkState(tryConnecting, "bug in tryConnectingOrphans");
log.warn(
"Block does not connect: {} prev {}",
block.getHashAsString(),
block.getPrevBlockHash());
orphanBlocks.put(block.getHash(), new OrphanBlock(block, filteredTxHashList, filteredTxn));
return false;
} else {
checkState(lock.isHeldByCurrentThread());
// It connects to somewhere on the chain. Not necessarily the top of the best known chain.
params.checkDifficultyTransitions(storedPrev, block, blockStore);
connectBlock(
block, storedPrev, shouldVerifyTransactions(), filteredTxHashList, filteredTxn);
}
if (tryConnecting) tryConnectingOrphans();
return true;
} finally {
lock.unlock();
}
}
/**
* Returns the hashes of the currently stored orphan blocks and then deletes them from this
* objects storage. Used by Peer when a filter exhaustion event has occurred and thus any orphan
* blocks that have been downloaded might be inaccurate/incomplete.
*/
public Set<Sha256Hash> drainOrphanBlocks() {
lock.lock();
try {
Set<Sha256Hash> hashes = new HashSet<Sha256Hash>(orphanBlocks.keySet());
orphanBlocks.clear();
return hashes;
} finally {
lock.unlock();
}
}
// expensiveChecks enables checks that require looking at blocks further back in the chain
// than the previous one when connecting (eg median timestamp check)
// It could be exposed, but for now we just set it to shouldVerifyTransactions()
private void connectBlock(
final Block block,
StoredBlock storedPrev,
boolean expensiveChecks,
@Nullable final List<Sha256Hash> filteredTxHashList,
@Nullable final Map<Sha256Hash, Transaction> filteredTxn)
throws BlockStoreException, VerificationException, PrunedException {
checkState(lock.isHeldByCurrentThread());
boolean filtered = filteredTxHashList != null && filteredTxn != null;
// Check that we aren't connecting a block that fails a checkpoint check
if (!params.passesCheckpoint(storedPrev.getHeight() + 1, block.getHash()))
throw new VerificationException(
"Block failed checkpoint lockin at " + (storedPrev.getHeight() + 1));
if (shouldVerifyTransactions()) {
checkNotNull(block.transactions);
for (Transaction tx : block.transactions)
if (!tx.isFinal(storedPrev.getHeight() + 1, block.getTimeSeconds()))
throw new VerificationException("Block contains non-final transaction");
}
StoredBlock head = getChainHead();
if (storedPrev.equals(head)) {
if (filtered && filteredTxn.size() > 0) {
log.debug(
"Block {} connects to top of best chain with {} transaction(s) of which we were sent {}",
block.getHashAsString(),
filteredTxHashList.size(),
filteredTxn.size());
for (Sha256Hash hash : filteredTxHashList) log.debug(" matched tx {}", hash);
}
if (expensiveChecks
&& block.getTimeSeconds() <= getMedianTimestampOfRecentBlocks(head, blockStore))
throw new VerificationException("Block's timestamp is too early");
// This block connects to the best known block, it is a normal continuation of the system.
TransactionOutputChanges txOutChanges = null;
if (shouldVerifyTransactions())
txOutChanges = connectTransactions(storedPrev.getHeight() + 1, block);
StoredBlock newStoredBlock =
addToBlockStore(
storedPrev, block.transactions == null ? block : block.cloneAsHeader(), txOutChanges);
setChainHead(newStoredBlock);
log.debug("Chain is now {} blocks high, running listeners", newStoredBlock.getHeight());
informListenersForNewBlock(
block, NewBlockType.BEST_CHAIN, filteredTxHashList, filteredTxn, newStoredBlock);
} else {
// This block connects to somewhere other than the top of the best known chain. We treat these
// differently.
//
// Note that we send the transactions to the wallet FIRST, even if we're about to re-organize
// this block
// to become the new best chain head. This simplifies handling of the re-org in the Wallet
// class.
StoredBlock newBlock = storedPrev.build(block);
boolean haveNewBestChain = newBlock.moreWorkThan(head);
if (haveNewBestChain) {
log.info("Block is causing a re-organize");
} else {
StoredBlock splitPoint = findSplit(newBlock, head, blockStore);
if (splitPoint != null && splitPoint.equals(newBlock)) {
// newStoredBlock is a part of the same chain, there's no fork. This happens when we
// receive a block
// that we already saw and linked into the chain previously, which isn't the chain head.
// Re-processing it is confusing for the wallet so just skip.
log.warn(
"Saw duplicated block in main chain at height {}: {}",
newBlock.getHeight(),
newBlock.getHeader().getHash());
return;
}
if (splitPoint == null) {
// This should absolutely never happen
// (lets not write the full block to disk to keep any bugs which allow this to happen
// from writing unreasonable amounts of data to disk)
throw new VerificationException("Block forks the chain but splitPoint is null");
} else {
// We aren't actually spending any transactions (yet) because we are on a fork
addToBlockStore(storedPrev, block);
int splitPointHeight = splitPoint.getHeight();
String splitPointHash = splitPoint.getHeader().getHashAsString();
log.info(
"Block forks the chain at height {}/block {}, but it did not cause a reorganize:\n{}",
splitPointHeight,
splitPointHash,
newBlock.getHeader().getHashAsString());
}
}
// We may not have any transactions if we received only a header, which can happen during fast
// catchup.
// If we do, send them to the wallet but state that they are on a side chain so it knows not
// to try and
// spend them until they become activated.
if (block.transactions != null || filtered) {
informListenersForNewBlock(
block, NewBlockType.SIDE_CHAIN, filteredTxHashList, filteredTxn, newBlock);
}
if (haveNewBestChain) handleNewBestChain(storedPrev, newBlock, block, expensiveChecks);
}
}
private void informListenersForNewBlock(
final Block block,
final NewBlockType newBlockType,
@Nullable final List<Sha256Hash> filteredTxHashList,
@Nullable final Map<Sha256Hash, Transaction> filteredTxn,
final StoredBlock newStoredBlock)
throws VerificationException {
// Notify the listeners of the new block, so the depth and workDone of stored transactions can
// be updated
// (in the case of the listener being a wallet). Wallets need to know how deep each transaction
// is so
// coinbases aren't used before maturity.
boolean first = true;
Set<Sha256Hash> falsePositives = Sets.newHashSet();
if (filteredTxHashList != null) falsePositives.addAll(filteredTxHashList);
for (final ListenerRegistration<BlockChainListener> registration : listeners) {
if (registration.executor == Threading.SAME_THREAD) {
informListenerForNewTransactions(
block,
newBlockType,
filteredTxHashList,
filteredTxn,
newStoredBlock,
first,
registration.listener,
falsePositives);
if (newBlockType == NewBlockType.BEST_CHAIN)
registration.listener.notifyNewBestBlock(newStoredBlock);
} else {
// Listener wants to be run on some other thread, so marshal it across here.
final boolean notFirst = !first;
registration.executor.execute(
new Runnable() {
@Override
public void run() {
try {
// We can't do false-positive handling when executing on another thread
Set<Sha256Hash> ignoredFalsePositives = Sets.newHashSet();
informListenerForNewTransactions(
block,
newBlockType,
filteredTxHashList,
filteredTxn,
newStoredBlock,
notFirst,
registration.listener,
ignoredFalsePositives);
if (newBlockType == NewBlockType.BEST_CHAIN)
registration.listener.notifyNewBestBlock(newStoredBlock);
} catch (VerificationException e) {
log.error("Block chain listener threw exception: ", e);
// Don't attempt to relay this back to the original peer thread if this was an
// async
// listener invocation.
// TODO: Make exception reporting a global feature and use it here.
}
}
});
}
first = false;
}
trackFalsePositives(falsePositives.size());
}
private static void informListenerForNewTransactions(
Block block,
NewBlockType newBlockType,
@Nullable List<Sha256Hash> filteredTxHashList,
@Nullable Map<Sha256Hash, Transaction> filteredTxn,
StoredBlock newStoredBlock,
boolean first,
BlockChainListener listener,
Set<Sha256Hash> falsePositives)
throws VerificationException {
if (block.transactions != null) {
// If this is not the first wallet, ask for the transactions to be duplicated before being
// given
// to the wallet when relevant. This ensures that if we have two connected wallets and a tx
// that
// is relevant to both of them, they don't end up accidentally sharing the same object (which
// can
// result in temporary in-memory corruption during re-orgs). See bug 257. We only duplicate in
// the case of multiple wallets to avoid an unnecessary efficiency hit in the common case.
sendTransactionsToListener(
newStoredBlock, newBlockType, listener, 0, block.transactions, !first, falsePositives);
} else if (filteredTxHashList != null) {
checkNotNull(filteredTxn);
// We must send transactions to listeners in the order they appeared in the block - thus we
// iterate over the
// set of hashes and call sendTransactionsToListener with individual txn when they have not
// already been
// seen in loose broadcasts - otherwise notifyTransactionIsInBlock on the hash.
int relativityOffset = 0;
for (Sha256Hash hash : filteredTxHashList) {
Transaction tx = filteredTxn.get(hash);
if (tx != null) {
sendTransactionsToListener(
newStoredBlock,
newBlockType,
listener,
relativityOffset,
Collections.singletonList(tx),
!first,
falsePositives);
} else {
if (listener.notifyTransactionIsInBlock(
hash, newStoredBlock, newBlockType, relativityOffset)) {
falsePositives.remove(hash);
}
}
relativityOffset++;
}
}
}
/** Gets the median timestamp of the last 11 blocks */
private static long getMedianTimestampOfRecentBlocks(StoredBlock storedBlock, BlockStore store)
throws BlockStoreException {
long[] timestamps = new long[11];
int unused = 9;
timestamps[10] = storedBlock.getHeader().getTimeSeconds();
while (unused >= 0 && (storedBlock = storedBlock.getPrev(store)) != null)
timestamps[unused--] = storedBlock.getHeader().getTimeSeconds();
Arrays.sort(timestamps, unused + 1, 11);
return timestamps[unused + (11 - unused) / 2];
}
/**
* Disconnect each transaction in the block (after reading it from the block store) Only called
* if(shouldVerifyTransactions())
*
* @throws PrunedException if block does not exist as a {@link StoredUndoableBlock} in the block
* store.
* @throws BlockStoreException if the block store had an underlying error or block does not exist
* in the block store at all.
*/
protected abstract void disconnectTransactions(StoredBlock block)
throws PrunedException, BlockStoreException;
/**
* Called as part of connecting a block when the new block results in a different chain having
* higher total work.
*
* <p>if (shouldVerifyTransactions) Either newChainHead needs to be in the block store as a
* FullStoredBlock, or (block != null && block.transactions != null)
*/
private void handleNewBestChain(
StoredBlock storedPrev, StoredBlock newChainHead, Block block, boolean expensiveChecks)
throws BlockStoreException, VerificationException, PrunedException {
checkState(lock.isHeldByCurrentThread());
// This chain has overtaken the one we currently believe is best. Reorganize is required.
//
// Firstly, calculate the block at which the chain diverged. We only need to examine the
// chain from beyond this block to find differences.
StoredBlock head = getChainHead();
final StoredBlock splitPoint = findSplit(newChainHead, head, blockStore);
log.info("Re-organize after split at height {}", splitPoint.getHeight());
log.info("Old chain head: {}", head.getHeader().getHashAsString());
log.info("New chain head: {}", newChainHead.getHeader().getHashAsString());
log.info("Split at block: {}", splitPoint.getHeader().getHashAsString());
// Then build a list of all blocks in the old part of the chain and the new part.
final LinkedList<StoredBlock> oldBlocks = getPartialChain(head, splitPoint, blockStore);
final LinkedList<StoredBlock> newBlocks = getPartialChain(newChainHead, splitPoint, blockStore);
// Disconnect each transaction in the previous main chain that is no longer in the new main
// chain
StoredBlock storedNewHead = splitPoint;
if (shouldVerifyTransactions()) {
for (StoredBlock oldBlock : oldBlocks) {
try {
disconnectTransactions(oldBlock);
} catch (PrunedException e) {
// We threw away the data we need to re-org this deep! We need to go back to a peer with
// full
// block contents and ask them for the relevant data then rebuild the indexs. Or we could
// just
// give up and ask the human operator to help get us unstuck (eg, rescan from the genesis
// block).
// TODO: Retry adding this block when we get a block with hash e.getHash()
throw e;
}
}
StoredBlock cursor;
// Walk in ascending chronological order.
for (Iterator<StoredBlock> it = newBlocks.descendingIterator(); it.hasNext(); ) {
cursor = it.next();
Block cursorBlock = cursor.getHeader();
if (expensiveChecks
&& cursorBlock.getTimeSeconds()
<= getMedianTimestampOfRecentBlocks(cursor.getPrev(blockStore), blockStore))
throw new VerificationException("Block's timestamp is too early during reorg");
TransactionOutputChanges txOutChanges;
if (cursor != newChainHead || block == null) txOutChanges = connectTransactions(cursor);
else txOutChanges = connectTransactions(newChainHead.getHeight(), block);
storedNewHead = addToBlockStore(storedNewHead, cursorBlock.cloneAsHeader(), txOutChanges);
}
} else {
// (Finally) write block to block store
storedNewHead = addToBlockStore(storedPrev, newChainHead.getHeader());
}
// Now inform the listeners. This is necessary so the set of currently active transactions (that
// we can spend)
// can be updated to take into account the re-organize. We might also have received new coins we
// didn't have
// before and our previous spends might have been undone.
for (final ListenerRegistration<BlockChainListener> registration : listeners) {
if (registration.executor == Threading.SAME_THREAD) {
// Short circuit the executor so we can propagate any exceptions.
// TODO: Do we really need to do this or should it be irrelevant?
registration.listener.reorganize(splitPoint, oldBlocks, newBlocks);
} else {
registration.executor.execute(
new Runnable() {
@Override
public void run() {
try {
registration.listener.reorganize(splitPoint, oldBlocks, newBlocks);
} catch (VerificationException e) {
log.error("Block chain listener threw exception during reorg", e);
}
}
});
}
}
// Update the pointer to the best known block.
setChainHead(storedNewHead);
}
/**
* Returns the set of contiguous blocks between 'higher' and 'lower'. Higher is included, lower is
* not.
*/
private static LinkedList<StoredBlock> getPartialChain(
StoredBlock higher, StoredBlock lower, BlockStore store) throws BlockStoreException {
checkArgument(higher.getHeight() > lower.getHeight(), "higher and lower are reversed");
LinkedList<StoredBlock> results = new LinkedList<StoredBlock>();
StoredBlock cursor = higher;
while (true) {
results.add(cursor);
cursor = checkNotNull(cursor.getPrev(store), "Ran off the end of the chain");
if (cursor.equals(lower)) break;
}
return results;
}
/**
* Locates the point in the chain at which newStoredBlock and chainHead diverge. Returns null if
* no split point was found (ie they are not part of the same chain). Returns newChainHead or
* chainHead if they don't actually diverge but are part of the same chain.
*/
private static StoredBlock findSplit(
StoredBlock newChainHead, StoredBlock oldChainHead, BlockStore store)
throws BlockStoreException {
StoredBlock currentChainCursor = oldChainHead;
StoredBlock newChainCursor = newChainHead;
// Loop until we find the block both chains have in common. Example:
//
// A -> B -> C -> D
// \--> E -> F -> G
//
// findSplit will return block B. oldChainHead = D and newChainHead = G.
while (!currentChainCursor.equals(newChainCursor)) {
if (currentChainCursor.getHeight() > newChainCursor.getHeight()) {
currentChainCursor = currentChainCursor.getPrev(store);
checkNotNull(currentChainCursor, "Attempt to follow an orphan chain");
} else {
newChainCursor = newChainCursor.getPrev(store);
checkNotNull(newChainCursor, "Attempt to follow an orphan chain");
}
}
return currentChainCursor;
}
/**
* @return the height of the best known chain, convenience for
* <tt>getChainHead().getHeight()</tt>.
*/
public int getBestChainHeight() {
return getChainHead().getHeight();
}
public enum NewBlockType {
BEST_CHAIN,
SIDE_CHAIN
}
private static void sendTransactionsToListener(
StoredBlock block,
NewBlockType blockType,
BlockChainListener listener,
int relativityOffset,
List<Transaction> transactions,
boolean clone,
Set<Sha256Hash> falsePositives)
throws VerificationException {
for (Transaction tx : transactions) {
try {
if (listener.isTransactionRelevant(tx)) {
falsePositives.remove(tx.getHash());
if (clone) tx = new Transaction(tx.params, tx.bitcoinSerialize());
listener.receiveFromBlock(tx, block, blockType, relativityOffset++);
}
} catch (ScriptException e) {
// We don't want scripts we don't understand to break the block chain so just note that this
// tx was
// not scanned here and continue.
log.warn("Failed to parse a script: " + e.toString());
} catch (ProtocolException e) {
// Failed to duplicate tx, should never happen.
throw new RuntimeException(e);
}
}
}
protected void setChainHead(StoredBlock chainHead) throws BlockStoreException {
doSetChainHead(chainHead);
synchronized (chainHeadLock) {
this.chainHead = chainHead;
}
}
/**
* For each block in orphanBlocks, see if we can now fit it on top of the chain and if so, do so.
*/
private void tryConnectingOrphans()
throws VerificationException, BlockStoreException, PrunedException {
checkState(lock.isHeldByCurrentThread());
// For each block in our orphan list, try and fit it onto the head of the chain. If we succeed
// remove it
// from the list and keep going. If we changed the head of the list at the end of the round try
// again until
// we can't fit anything else on the top.
//
// This algorithm is kind of crappy, we should do a topo-sort then just connect them in order,
// but for small
// numbers of orphan blocks it does OK.
int blocksConnectedThisRound;
do {
blocksConnectedThisRound = 0;
Iterator<OrphanBlock> iter = orphanBlocks.values().iterator();
while (iter.hasNext()) {
OrphanBlock orphanBlock = iter.next();
// Look up the blocks previous.
StoredBlock prev = getStoredBlockInCurrentScope(orphanBlock.block.getPrevBlockHash());
if (prev == null) {
// This is still an unconnected/orphan block.
log.debug(" but it is not connectable right now");
continue;
}
// Otherwise we can connect it now.
// False here ensures we don't recurse infinitely downwards when connecting huge chains.
log.info("Connected orphan {}", orphanBlock.block.getHash());
add(orphanBlock.block, false, orphanBlock.filteredTxHashes, orphanBlock.filteredTxn);
iter.remove();
blocksConnectedThisRound++;
}
if (blocksConnectedThisRound > 0) {
log.info("Connected {} orphan blocks.", blocksConnectedThisRound);
}
} while (blocksConnectedThisRound > 0);
}
/** Returns true if any connected wallet considers any transaction in the block to be relevant. */
private boolean containsRelevantTransactions(Block block) {
// Does not need to be locked.
for (Transaction tx : block.transactions) {
try {
for (final ListenerRegistration<BlockChainListener> registration : listeners) {
if (registration.executor != Threading.SAME_THREAD) continue;
if (registration.listener.isTransactionRelevant(tx)) return true;
}
} catch (ScriptException e) {
// We don't want scripts we don't understand to break the block chain so just note that this
// tx was
// not scanned here and continue.
log.warn("Failed to parse a script: " + e.toString());
}
}
return false;
}
/**
* Returns the block at the head of the current best chain. This is the block which represents the
* greatest amount of cumulative work done.
*/
public StoredBlock getChainHead() {
synchronized (chainHeadLock) {
return chainHead;
}
}
/**
* An orphan block is one that does not connect to the chain anywhere (ie we can't find its
* parent, therefore it's an orphan). Typically this occurs when we are downloading the chain and
* didn't reach the head yet, and/or if a block is solved whilst we are downloading. It's possible
* that we see a small amount of orphan blocks which chain together, this method tries walking
* backwards through the known orphan blocks to find the bottom-most.
*
* @return from or one of froms parents, or null if "from" does not identify an orphan block
*/
@Nullable
public Block getOrphanRoot(Sha256Hash from) {
lock.lock();
try {
OrphanBlock cursor = orphanBlocks.get(from);
if (cursor == null) return null;
OrphanBlock tmp;
while ((tmp = orphanBlocks.get(cursor.block.getPrevBlockHash())) != null) {
cursor = tmp;
}
return cursor.block;
} finally {
lock.unlock();
}
}
/** Returns true if the given block is currently in the orphan blocks list. */
public boolean isOrphan(Sha256Hash block) {
lock.lock();
try {
return orphanBlocks.containsKey(block);
} finally {
lock.unlock();
}
}
/**
* Returns an estimate of when the given block will be reached, assuming a perfect 10 minute
* average for each block. This is useful for turning transaction lock times into human readable
* times. Note that a height in the past will still be estimated, even though the time of solving
* is actually known (we won't scan backwards through the chain to obtain the right answer).
*/
public Date estimateBlockTime(int height) {
synchronized (chainHeadLock) {
long offset = height - chainHead.getHeight();
long headTime = chainHead.getHeader().getTimeSeconds();
long estimated =
(headTime * 1000) + (1000L * 30L * 1L * offset); // 2 blocks per minute
return new Date(estimated);
}
}
/**
* Returns a future that completes when the block chain has reached the given height. Yields the
* {@link StoredBlock} of the block that reaches that height first. The future completes on a peer
* thread.
*/
public ListenableFuture<StoredBlock> getHeightFuture(final int height) {
final SettableFuture<StoredBlock> result = SettableFuture.create();
addListener(
new AbstractBlockChainListener() {
@Override
public void notifyNewBestBlock(StoredBlock block) throws VerificationException {
if (block.getHeight() >= height) {
removeListener(this);
result.set(block);
}
}
},
Threading.SAME_THREAD);
return result;
}
/**
* The false positive rate is the average over all blockchain transactions of:
*
* <p>- 1.0 if the transaction was false-positive (was irrelevant to all listeners) - 0.0 if the
* transaction was relevant or filtered out
*/
public double getFalsePositiveRate() {
return falsePositiveRate;
}
/*
* We completed handling of a filtered block. Update false-positive estimate based
* on the total number of transactions in the original block.
*
* count includes filtered transactions, transactions that were passed in and were relevant
* and transactions that were false positives (i.e. includes all transactions in the block).
*/
protected void trackFilteredTransactions(int count) {
// Track non-false-positives in batch. Each non-false-positive counts as
// 0.0 towards the estimate.
//
// This is slightly off because we are applying false positive tracking before non-FP tracking,
// which counts FP as if they came at the beginning of the block. Assuming uniform FP
// spread in a block, this will somewhat underestimate the FP rate (5% for 1000 tx block).
double alphaDecay = Math.pow(1 - FP_ESTIMATOR_ALPHA, count);
// new_rate = alpha_decay * new_rate
falsePositiveRate = alphaDecay * falsePositiveRate;
double betaDecay = Math.pow(1 - FP_ESTIMATOR_BETA, count);
// trend = beta * (new_rate - old_rate) + beta_decay * trend
falsePositiveTrend =
FP_ESTIMATOR_BETA * count * (falsePositiveRate - previousFalsePositiveRate)
+ betaDecay * falsePositiveTrend;
// new_rate += alpha_decay * trend
falsePositiveRate += alphaDecay * falsePositiveTrend;
// Stash new_rate in old_rate
previousFalsePositiveRate = falsePositiveRate;
}
/* Irrelevant transactions were received. Update false-positive estimate. */
void trackFalsePositives(int count) {
// Track false positives in batch by adding alpha to the false positive estimate once per count.
// Each false positive counts as 1.0 towards the estimate.
falsePositiveRate += FP_ESTIMATOR_ALPHA * count;
if (count > 0)
log.debug(
"{} false positives, current rate = {} trend = {}",
count,
falsePositiveRate,
falsePositiveTrend);
}
/** Resets estimates of false positives. Used when the filter is sent to the peer. */
public void resetFalsePositiveEstimate() {
falsePositiveRate = 0;
falsePositiveTrend = 0;
previousFalsePositiveRate = 0;
}
}
/**
* Handles high-level message (de)serialization for peers, acting as the bridge between the {@link
* org.bitcoinj.net} classes and {@link Peer}.
*/
public abstract class PeerSocketHandler extends AbstractTimeoutHandler implements StreamConnection {
private static final Logger log = LoggerFactory.getLogger(PeerSocketHandler.class);
private final MessageSerializer serializer;
protected PeerAddress peerAddress;
// If we close() before we know our writeTarget, set this to true to call
// writeTarget.closeConnection() right away.
private boolean closePending = false;
// writeTarget will be thread-safe, and may call into PeerGroup, which calls us, so we should call
// it unlocked
@VisibleForTesting protected MessageWriteTarget writeTarget = null;
// The ByteBuffers passed to us from the writeTarget are static in size, and usually smaller than
// some messages we
// will receive. For SPV clients, this should be rare (ie we're mostly dealing with small
// transactions), but for
// messages which are larger than the read buffer, we have to keep a temporary buffer with its
// bytes.
private byte[] largeReadBuffer;
private int largeReadBufferPos;
private BitcoinSerializer.BitcoinPacketHeader header;
private Lock lock = Threading.lock("PeerSocketHandler");
public PeerSocketHandler(NetworkParameters params, InetSocketAddress remoteIp) {
checkNotNull(params);
serializer = params.getDefaultSerializer();
this.peerAddress = new PeerAddress(remoteIp);
}
public PeerSocketHandler(NetworkParameters params, PeerAddress peerAddress) {
checkNotNull(params);
serializer = params.getDefaultSerializer();
this.peerAddress = checkNotNull(peerAddress);
}
/**
* Sends the given message to the peer. Due to the asynchronousness of network programming, there
* is no guarantee the peer will have received it. Throws NotYetConnectedException if we are not
* yet connected to the remote peer. TODO: Maybe use something other than the unchecked
* NotYetConnectedException here
*/
public void sendMessage(Message message) throws NotYetConnectedException {
lock.lock();
try {
if (writeTarget == null) throw new NotYetConnectedException();
} finally {
lock.unlock();
}
// TODO: Some round-tripping could be avoided here
ByteArrayOutputStream out = new ByteArrayOutputStream();
try {
serializer.serialize(message, out);
writeTarget.writeBytes(out.toByteArray());
} catch (IOException e) {
exceptionCaught(e);
}
}
/**
* Closes the connection to the peer if one exists, or immediately closes the connection as soon
* as it opens
*/
public void close() {
lock.lock();
try {
if (writeTarget == null) {
closePending = true;
return;
}
} finally {
lock.unlock();
}
writeTarget.closeConnection();
}
@Override
protected void timeoutOccurred() {
log.info("{}: Timed out", getAddress());
close();
}
/** Called every time a message is received from the network */
protected abstract void processMessage(Message m) throws Exception;
@Override
public int receiveBytes(ByteBuffer buff) {
checkArgument(
buff.position() == 0
&& buff.capacity() >= BitcoinSerializer.BitcoinPacketHeader.HEADER_LENGTH + 4);
try {
// Repeatedly try to deserialize messages until we hit a BufferUnderflowException
boolean firstMessage = true;
while (true) {
// If we are in the middle of reading a message, try to fill that one first, before we
// expect another
if (largeReadBuffer != null) {
// This can only happen in the first iteration
checkState(firstMessage);
// Read new bytes into the largeReadBuffer
int bytesToGet = Math.min(buff.remaining(), largeReadBuffer.length - largeReadBufferPos);
buff.get(largeReadBuffer, largeReadBufferPos, bytesToGet);
largeReadBufferPos += bytesToGet;
// Check the largeReadBuffer's status
if (largeReadBufferPos == largeReadBuffer.length) {
// ...processing a message if one is available
processMessage(serializer.deserializePayload(header, ByteBuffer.wrap(largeReadBuffer)));
largeReadBuffer = null;
header = null;
firstMessage = false;
} else // ...or just returning if we don't have enough bytes yet
return buff.position();
}
// Now try to deserialize any messages left in buff
Message message;
int preSerializePosition = buff.position();
try {
message = serializer.deserialize(buff);
} catch (BufferUnderflowException e) {
// If we went through the whole buffer without a full message, we need to use the
// largeReadBuffer
if (firstMessage && buff.limit() == buff.capacity()) {
// ...so reposition the buffer to 0 and read the next message header
buff.position(0);
try {
serializer.seekPastMagicBytes(buff);
header = serializer.deserializeHeader(buff);
// Initialize the largeReadBuffer with the next message's size and fill it with any
// bytes
// left in buff
largeReadBuffer = new byte[header.size];
largeReadBufferPos = buff.remaining();
buff.get(largeReadBuffer, 0, largeReadBufferPos);
} catch (BufferUnderflowException e1) {
// If we went through a whole buffer's worth of bytes without getting a header, give
// up
// In cases where the buff is just really small, we could create a second
// largeReadBuffer
// that we use to deserialize the magic+header, but that is rather complicated when
// the buff
// should probably be at least that big anyway (for efficiency)
throw new ProtocolException(
"No magic bytes+header after reading " + buff.capacity() + " bytes");
}
} else {
// Reposition the buffer to its original position, which saves us from skipping messages
// by
// seeking past part of the magic bytes before all of them are in the buffer
buff.position(preSerializePosition);
}
return buff.position();
}
// Process our freshly deserialized message
processMessage(message);
firstMessage = false;
}
} catch (Exception e) {
exceptionCaught(e);
return -1; // Returning -1 also throws an IllegalStateException upstream and kills the
// connection
}
}
/**
* Sets the {@link MessageWriteTarget} used to write messages to the peer. This should almost
* never be called, it is called automatically by {@link org.bitcoinj.net.NioClient} or {@link
* org.bitcoinj.net.NioClientManager} once the socket finishes initialization.
*/
@Override
public void setWriteTarget(MessageWriteTarget writeTarget) {
checkArgument(writeTarget != null);
lock.lock();
boolean closeNow = false;
try {
checkArgument(this.writeTarget == null);
closeNow = closePending;
this.writeTarget = writeTarget;
} finally {
lock.unlock();
}
if (closeNow) writeTarget.closeConnection();
}
@Override
public int getMaxMessageSize() {
return Message.MAX_SIZE;
}
/** @return the IP address and port of peer. */
public PeerAddress getAddress() {
return peerAddress;
}
/** Catch any exceptions, logging them and then closing the channel. */
private void exceptionCaught(Exception e) {
PeerAddress addr = getAddress();
String s = addr == null ? "?" : addr.toString();
if (e instanceof ConnectException || e instanceof IOException) {
// Short message for network errors
log.info(s + " - " + e.getMessage());
} else {
log.warn(s + " - ", e);
Thread.UncaughtExceptionHandler handler = Threading.uncaughtExceptionHandler;
if (handler != null) handler.uncaughtException(Thread.currentThread(), e);
}
close();
}
}
@Test
public void peerGroupWalletIntegration() throws Exception {
// Make sure we can create spends, and that they are announced. Then do the same with offline
// mode.
// Set up connections and block chain.
VersionMessage ver = new VersionMessage(params, 2);
ver.localServices = VersionMessage.NODE_NETWORK;
InboundMessageQueuer p1 = connectPeer(1, ver);
InboundMessageQueuer p2 = connectPeer(2);
// Send ourselves a bit of money.
Block b1 = FakeTxBuilder.makeSolvedTestBlock(blockStore, address);
inbound(p1, b1);
pingAndWait(p1);
assertNull(outbound(p1));
assertEquals(FIFTY_COINS, wallet.getBalance());
// Check that the wallet informs us of changes in confidence as the transaction ripples across
// the network.
final Transaction[] transactions = new Transaction[1];
wallet.addEventListener(
new AbstractWalletEventListener() {
@Override
public void onTransactionConfidenceChanged(Wallet wallet, Transaction tx) {
transactions[0] = tx;
}
});
// Now create a spend, and expect the announcement on p1.
Address dest = new ECKey().toAddress(params);
Wallet.SendResult sendResult = wallet.sendCoins(peerGroup, dest, COIN);
assertNotNull(sendResult.tx);
Threading.waitForUserCode();
assertFalse(sendResult.broadcastComplete.isDone());
assertEquals(transactions[0], sendResult.tx);
assertEquals(0, transactions[0].getConfidence().numBroadcastPeers());
transactions[0] = null;
Transaction t1;
{
peerGroup.waitForJobQueue();
Message m = outbound(p1);
// Hack: bloom filters are recalculated asynchronously to sending transactions to avoid lock
// inversion, so we might or might not get the filter/mempool message first or second.
while (!(m instanceof Transaction)) m = outbound(p1);
t1 = (Transaction) m;
}
assertNotNull(t1);
// 49 BTC in change.
assertEquals(valueOf(49, 0), t1.getValueSentToMe(wallet));
// The future won't complete until it's heard back from the network on p2.
InventoryMessage inv = new InventoryMessage(params);
inv.addTransaction(t1);
inbound(p2, inv);
pingAndWait(p2);
Threading.waitForUserCode();
assertTrue(sendResult.broadcastComplete.isDone());
assertEquals(transactions[0], sendResult.tx);
assertEquals(1, transactions[0].getConfidence().numBroadcastPeers());
// Confirm it.
Block b2 = FakeTxBuilder.createFakeBlock(blockStore, t1).block;
inbound(p1, b2);
pingAndWait(p1);
assertNull(outbound(p1));
// Do the same thing with an offline transaction.
peerGroup.removeWallet(wallet);
Wallet.SendRequest req = Wallet.SendRequest.to(dest, valueOf(2, 0));
req.ensureMinRequiredFee = false;
Transaction t3 = checkNotNull(wallet.sendCoinsOffline(req));
assertNull(outbound(p1)); // Nothing sent.
// Add the wallet to the peer group (simulate initialization). Transactions should be announced.
peerGroup.addWallet(wallet);
// Transaction announced to the first peer. No extra Bloom filter because no change address was
// needed.
assertEquals(t3.getHash(), ((Transaction) outbound(p1)).getHash());
}
@Test
public void testAppearedAtChainHeightDepthAndWorkDone() throws Exception {
// Test the TransactionConfidence appearedAtChainHeight, depth and workDone field are stored.
BlockChain chain = new BlockChain(params, myWallet, new MemoryBlockStore(params));
final ArrayList<Transaction> txns = new ArrayList<Transaction>(2);
myWallet.addEventListener(
new AbstractWalletEventListener() {
@Override
public void onCoinsReceived(
Wallet wallet, Transaction tx, Coin prevBalance, Coin newBalance) {
txns.add(tx);
}
});
// Start by building two blocks on top of the genesis block.
Block b1 = params.getGenesisBlock().createNextBlock(myAddress);
BigInteger work1 = b1.getWork();
assertTrue(work1.signum() > 0);
Block b2 = b1.createNextBlock(myAddress);
BigInteger work2 = b2.getWork();
assertTrue(work2.signum() > 0);
assertTrue(chain.add(b1));
assertTrue(chain.add(b2));
// We now have the following chain:
// genesis -> b1 -> b2
// Check the transaction confidence levels are correct before wallet roundtrip.
Threading.waitForUserCode();
assertEquals(2, txns.size());
TransactionConfidence confidence0 = txns.get(0).getConfidence();
TransactionConfidence confidence1 = txns.get(1).getConfidence();
assertEquals(1, confidence0.getAppearedAtChainHeight());
assertEquals(2, confidence1.getAppearedAtChainHeight());
assertEquals(2, confidence0.getDepthInBlocks());
assertEquals(1, confidence1.getDepthInBlocks());
// Roundtrip the wallet and check it has stored the depth and workDone.
Wallet rebornWallet = roundTrip(myWallet);
Set<Transaction> rebornTxns = rebornWallet.getTransactions(false);
assertEquals(2, rebornTxns.size());
// The transactions are not guaranteed to be in the same order so sort them to be in chain
// height order if required.
Iterator<Transaction> it = rebornTxns.iterator();
Transaction txA = it.next();
Transaction txB = it.next();
Transaction rebornTx0, rebornTx1;
if (txA.getConfidence().getAppearedAtChainHeight() == 1) {
rebornTx0 = txA;
rebornTx1 = txB;
} else {
rebornTx0 = txB;
rebornTx1 = txA;
}
TransactionConfidence rebornConfidence0 = rebornTx0.getConfidence();
TransactionConfidence rebornConfidence1 = rebornTx1.getConfidence();
assertEquals(1, rebornConfidence0.getAppearedAtChainHeight());
assertEquals(2, rebornConfidence1.getAppearedAtChainHeight());
assertEquals(2, rebornConfidence0.getDepthInBlocks());
assertEquals(1, rebornConfidence1.getDepthInBlocks());
}
/**
* This class maintains a set of {@link StoredClientChannel}s, automatically (re)broadcasting the
* contract transaction and broadcasting the refund transaction over the given {@link
* TransactionBroadcaster}.
*/
public class StoredPaymentChannelClientStates implements WalletExtension {
private static final Logger log = LoggerFactory.getLogger(StoredPaymentChannelClientStates.class);
static final String EXTENSION_ID = StoredPaymentChannelClientStates.class.getName();
static final int MAX_SECONDS_TO_WAIT_FOR_BROADCASTER_TO_BE_SET = 10;
@GuardedBy("lock")
@VisibleForTesting
final HashMultimap<Sha256Hash, StoredClientChannel> mapChannels = HashMultimap.create();
@VisibleForTesting final Timer channelTimeoutHandler = new Timer(true);
private Wallet containingWallet;
private final SettableFuture<TransactionBroadcaster> announcePeerGroupFuture =
SettableFuture.create();
protected final ReentrantLock lock = Threading.lock("StoredPaymentChannelClientStates");
/**
* Creates a new StoredPaymentChannelClientStates and associates it with the given {@link Wallet}
* and {@link TransactionBroadcaster} which are used to complete and announce contract and refund
* transactions.
*/
public StoredPaymentChannelClientStates(
@Nullable Wallet containingWallet, TransactionBroadcaster announcePeerGroup) {
setTransactionBroadcaster(announcePeerGroup);
this.containingWallet = containingWallet;
}
/**
* Creates a new StoredPaymentChannelClientStates and associates it with the given {@link Wallet}
*
* <p>Use this constructor if you use WalletAppKit, it will provide the broadcaster for you (no
* need to call the setter)
*/
public StoredPaymentChannelClientStates(@Nullable Wallet containingWallet) {
this.containingWallet = containingWallet;
}
/**
* Use this setter if the broadcaster is not available during instantiation and you're not using
* WalletAppKit. This setter will let you delay the setting of the broadcaster until the Bitcoin
* network is ready.
*
* @param transactionBroadcaster which is used to complete and announce contract and refund
* transactions.
*/
public final void setTransactionBroadcaster(TransactionBroadcaster transactionBroadcaster) {
this.announcePeerGroupFuture.set(checkNotNull(transactionBroadcaster));
}
/** Returns this extension from the given wallet, or null if no such extension was added. */
@Nullable
public static StoredPaymentChannelClientStates getFromWallet(Wallet wallet) {
return (StoredPaymentChannelClientStates) wallet.getExtensions().get(EXTENSION_ID);
}
/**
* 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();
}
}
/**
* Returns the number of seconds from now until this servers next channel will expire, or zero if
* no unexpired channels found.
*/
public long getSecondsUntilExpiry(Sha256Hash id) {
lock.lock();
try {
final Set<StoredClientChannel> setChannels = mapChannels.get(id);
final long nowSeconds = Utils.currentTimeSeconds();
int earliestTime = Integer.MAX_VALUE;
for (StoredClientChannel channel : setChannels) {
synchronized (channel) {
if (channel.expiryTimeSeconds() > nowSeconds)
earliestTime = Math.min(earliestTime, (int) channel.expiryTimeSeconds());
}
}
return earliestTime == Integer.MAX_VALUE ? 0 : earliestTime - nowSeconds;
} finally {
lock.unlock();
}
}
/** Finds an inactive channel with the given id and returns it, or returns null. */
@Nullable
StoredClientChannel getUsableChannelForServerID(Sha256Hash id) {
lock.lock();
try {
Set<StoredClientChannel> setChannels = mapChannels.get(id);
for (StoredClientChannel channel : setChannels) {
synchronized (channel) {
// Check if the channel is usable (has money, inactive) and if so, activate it.
log.info(
"Considering channel {} contract {}", channel.hashCode(), channel.contract.getHash());
if (channel.close != null || channel.valueToMe.equals(Coin.ZERO)) {
log.info(" ... but is closed or empty");
continue;
}
if (!channel.active) {
log.info(" ... activating");
channel.active = true;
return channel;
}
log.info(" ... but is already active");
}
}
} finally {
lock.unlock();
}
return null;
}
/** Finds a channel with the given id and contract hash and returns it, or returns null. */
@Nullable
StoredClientChannel getChannel(Sha256Hash id, Sha256Hash contractHash) {
lock.lock();
try {
Set<StoredClientChannel> setChannels = mapChannels.get(id);
for (StoredClientChannel channel : setChannels) {
if (channel.contract.getHash().equals(contractHash)) return channel;
}
return null;
} finally {
lock.unlock();
}
}
/**
* Notifies the set of stored states that a channel has been updated. Use to notify the wallet of
* an update to this wallet extension.
*/
void updatedChannel(final StoredClientChannel channel) {
log.info("Stored client channel {} was updated", channel.hashCode());
containingWallet.addOrUpdateExtension(this);
}
/**
* Adds the given channel to this set of stored states, broadcasting the contract and refund
* transactions when the channel expires and notifies the wallet of an update to this wallet
* extension
*/
void putChannel(final StoredClientChannel channel) {
putChannel(channel, true);
}
// Adds this channel and optionally notifies the wallet of an update to this extension (used
// during deserialize)
private void putChannel(final StoredClientChannel channel, boolean updateWallet) {
lock.lock();
try {
mapChannels.put(channel.id, channel);
channelTimeoutHandler.schedule(
new TimerTask() {
@Override
public void run() {
TransactionBroadcaster announcePeerGroup = getAnnouncePeerGroup();
removeChannel(channel);
announcePeerGroup.broadcastTransaction(channel.contract);
announcePeerGroup.broadcastTransaction(channel.refund);
}
// Add the difference between real time and Utils.now() so that test-cases can use a
// mock clock.
},
new Date(
channel.expiryTimeSeconds() * 1000
+ (System.currentTimeMillis() - Utils.currentTimeMillis())));
} finally {
lock.unlock();
}
if (updateWallet) updatedChannel(channel);
}
/**
* If the peer group has not been set for MAX_SECONDS_TO_WAIT_FOR_BROADCASTER_TO_BE_SET seconds,
* then the programmer probably forgot to set it and we should throw exception.
*/
private TransactionBroadcaster getAnnouncePeerGroup() {
try {
return announcePeerGroupFuture.get(
MAX_SECONDS_TO_WAIT_FOR_BROADCASTER_TO_BE_SET, TimeUnit.SECONDS);
} catch (InterruptedException e) {
throw new RuntimeException(e);
} catch (ExecutionException e) {
throw new RuntimeException(e);
} catch (TimeoutException e) {
String err = "Transaction broadcaster not set";
log.error(err);
throw new RuntimeException(err, e);
}
}
/**
* Removes the channel with the given id from this set of stored states and notifies the wallet of
* an update to this wallet extension.
*
* <p>Note that the channel will still have its contract and refund transactions broadcast via the
* connected {@link TransactionBroadcaster} as long as this {@link
* StoredPaymentChannelClientStates} continues to exist in memory.
*/
void removeChannel(StoredClientChannel channel) {
lock.lock();
try {
mapChannels.remove(channel.id, channel);
} finally {
lock.unlock();
}
updatedChannel(channel);
}
@Override
public String getWalletExtensionID() {
return EXTENSION_ID;
}
@Override
public boolean isWalletExtensionMandatory() {
return false;
}
@Override
public byte[] serializeWalletExtension() {
lock.lock();
try {
ClientState.StoredClientPaymentChannels.Builder builder =
ClientState.StoredClientPaymentChannels.newBuilder();
for (StoredClientChannel channel : mapChannels.values()) {
// First a few asserts to make sure things won't break
checkState(
channel.valueToMe.signum() >= 0
&& channel.valueToMe.compareTo(NetworkParameters.MAX_MONEY) < 0);
checkState(
channel.refundFees.signum() >= 0
&& channel.refundFees.compareTo(NetworkParameters.MAX_MONEY) < 0);
checkNotNull(channel.myKey.getPubKey());
checkState(channel.refund.getConfidence().getSource() == TransactionConfidence.Source.SELF);
final ClientState.StoredClientPaymentChannel.Builder value =
ClientState.StoredClientPaymentChannel.newBuilder()
.setId(ByteString.copyFrom(channel.id.getBytes()))
.setContractTransaction(ByteString.copyFrom(channel.contract.bitcoinSerialize()))
.setRefundTransaction(ByteString.copyFrom(channel.refund.bitcoinSerialize()))
.setMyKey(
ByteString.copyFrom(new byte[0])) // Not used, but protobuf message requires
.setMyPublicKey(ByteString.copyFrom(channel.myKey.getPubKey()))
.setValueToMe(channel.valueToMe.value)
.setRefundFees(channel.refundFees.value);
if (channel.close != null)
value.setCloseTransactionHash(ByteString.copyFrom(channel.close.getHash().getBytes()));
builder.addChannels(value);
}
return builder.build().toByteArray();
} finally {
lock.unlock();
}
}
@Override
public void deserializeWalletExtension(Wallet containingWallet, byte[] data) throws Exception {
lock.lock();
try {
checkState(this.containingWallet == null || this.containingWallet == containingWallet);
this.containingWallet = containingWallet;
NetworkParameters params = containingWallet.getParams();
ClientState.StoredClientPaymentChannels states =
ClientState.StoredClientPaymentChannels.parseFrom(data);
for (ClientState.StoredClientPaymentChannel storedState : states.getChannelsList()) {
Transaction refundTransaction =
params
.getDefaultSerializer()
.makeTransaction(storedState.getRefundTransaction().toByteArray());
refundTransaction.getConfidence().setSource(TransactionConfidence.Source.SELF);
ECKey myKey =
(storedState.getMyKey().isEmpty())
? containingWallet.findKeyFromPubKey(storedState.getMyPublicKey().toByteArray())
: ECKey.fromPrivate(storedState.getMyKey().toByteArray());
StoredClientChannel channel =
new StoredClientChannel(
Sha256Hash.wrap(storedState.getId().toByteArray()),
params
.getDefaultSerializer()
.makeTransaction(storedState.getContractTransaction().toByteArray()),
refundTransaction,
myKey,
Coin.valueOf(storedState.getValueToMe()),
Coin.valueOf(storedState.getRefundFees()),
false);
if (storedState.hasCloseTransactionHash()) {
Sha256Hash closeTxHash =
Sha256Hash.wrap(storedState.getCloseTransactionHash().toByteArray());
channel.close = containingWallet.getTransaction(closeTxHash);
}
putChannel(channel, false);
}
} finally {
lock.unlock();
}
}
@Override
public String toString() {
lock.lock();
try {
StringBuilder buf = new StringBuilder("Client payment channel states:\n");
for (StoredClientChannel channel : mapChannels.values())
buf.append(" ").append(channel).append("\n");
return buf.toString();
} finally {
lock.unlock();
}
}
}
