/**
* @param BlockHeaderInterface $header
* @return $this
* @throws \Exception
*/
public function save(BlockHeaderInterface $header)
{
$height = $this->height();
$this->index->save('height', ++$height);
$key = $this->cacheIndex($height);
$this->index->save($key, $header->getBlockHash());
return $this;
}
/**
* @param BufferInterface $hash
* @param BlockHeaderInterface $header
* @param bool $checkPow
* @return $this
*/
public function check(BufferInterface $hash, BlockHeaderInterface $header, $checkPow = true)
{
try {
if ($checkPow) {
$this->pow->check($hash, $header->getBits());
}
} catch (\Exception $e) {
throw new \RuntimeException('Headers::check() - failed validating header proof-of-work');
}
return $this;
}
/**
* @param ChainState $state
* @param BlockHeaderInterface $header
* @return BlockIndex
*/
public function accept(ChainState $state, BlockHeaderInterface $header)
{
$hash = $header->getHash();
if ($state->getChain()->containsHash($hash)) {
// todo: check for rejected block
return $this->db->fetchIndex($hash);
}
$prevIndex = $state->getChain()->getIndex();
$index = $this->headerCheck->check($header)->checkContextual($state, $header)->makeIndex($prevIndex, $header);
$this->db->insertIndexBatch($prevIndex, [$index]);
$state->getChain()->updateTip($index);
return $index;
}
/**
* @param BlockHeaderInterface $header
* @return bool
* @throws \Exception
*/
public function checkHeader(BlockHeaderInterface $header)
{
$math = $this->math;
$target = $this->difficulty->getTarget($header->getBits());
if ($math->cmp($target, 0) == 0 || $math->cmp($target, $this->limit()) > 0) {
throw new \Exception('nBits below minimum work');
}
$hashInt = $math->hexDec($header->getBlockHash());
if ($math->cmp($hashInt, $target) > 0) {
throw new \Exception("Hash doesn't match nBits");
}
return true;
}
/**
* @param BlockHeaderInterface $header
* @return Chain
*/
public function findTipForNext(BlockHeaderInterface $header)
{
foreach ($this->states as $state) {
$tTip = $state->getChain();
$tipHash = $tTip->getIndex()->getHash();
if ($header->getPrevBlock() == $tipHash) {
$tip = $tTip;
}
}
if (!isset($tip)) {
throw new \RuntimeException('No tip found for this Header');
}
return $tip;
}
/**
* @param BlockHeaderInterface $header
* @return $this
*/
public function delete(BlockHeaderInterface $header)
{
$hash = $header->getBlockHash();
$this->hash()->delete($this->height()->fetch($hash));
$this->height()->delete($hash);
return $this;
}
/**
* Process a block against the given state of the chain.
* @param BlockHeaderInterface $header
* @return bool
*/
public function process(BlockHeaderInterface $header)
{
// Ignore the genesis block
$hash = $header->getBlockHash();
if ($hash === $this->genesis->getBlockHash()) {
return true;
}
if ($this->index()->height()->contains($hash)) {
return true;
}
try {
// Attempt to add it to the chain
$this->add($header);
$this->pow->checkHeader($header);
$result = true;
} catch (BlockPrevNotFound $e) {
// If it fails because it doesn't elongate the chain, process it as an orphan.
// Result will be determined
$result = $this->processOrphan($header);
} catch (BlockPowError $e) {
$result = false;
// Invalid block.
}
return $result;
}
/**
* @param TransactionInterface|null $coinbaseTx
* @return Block
* @throws \BitWasp\Bitcoin\Exceptions\MerkleTreeEmpty
*/
public function run(TransactionInterface $coinbaseTx = null)
{
$nonce = '0';
$maxNonce = $this->math->pow(2, 32);
// Allow user supplied transactions
if ($coinbaseTx == null) {
$coinbaseTx = new Transaction();
$coinbaseTx->getInputs()->addInput(new TransactionInput('0000000000000000000000000000000000000000000000000000000000000000', 4294967295.0));
$coinbaseTx->getOutputs()->addOutput(new TransactionOutput(5000000000.0, $this->script));
}
$inputs = $coinbaseTx->getInputs();
$found = false;
$usingDiff = $this->lastBlockHeader->getBits();
$diff = new Difficulty($this->math);
$target = $diff->getTarget($usingDiff);
while (false === $found) {
// Set coinbase script, and build Merkle tree & block header.
$inputs->getInput(0)->setScript($this->getCoinbaseScriptBuf());
$transactions = new TransactionCollection(array_merge(array($coinbaseTx), $this->transactions->getTransactions()));
$merkleRoot = new MerkleRoot($this->math, $transactions);
$merkleHash = $merkleRoot->calculateHash();
$header = new BlockHeader($this->version, $this->lastBlockHeader->getBlockHash(), $merkleHash, $this->timestamp, $usingDiff, '0');
$t = microtime(true);
// Loop through all nonces (up to 2^32). Restart after modifying extranonce.
while ($this->math->cmp($header->getNonce(), $maxNonce) <= 0) {
$header->setNonce($this->math->add($header->getNonce(), '1'));
$hash = (new Parser())->writeBytes(32, Hash::sha256d($header->getBuffer()), true)->getBuffer();
if ($this->math->cmp($hash->getInt(), $target) <= 0) {
$block = new Block($this->math, $header, $transactions);
return $block;
}
if ($this->report && $this->math->cmp($this->math->mod($header->getNonce(), 100000), '0') == 0) {
$time = microtime(true) - $t;
$khash = $nonce / $time / 1000;
echo "extraNonce[{$this->extraNonce}] nonce[{$nonce}] time[{$time}] khash/s[{$khash}] \n";
}
}
// Whenever we exceed 2^32, increment extraNonce and reset $nonce
$this->extraNonce++;
$nonce = '0';
}
}
/**
* @param BlockHeaderInterface $header
* @return bool
* @throws \Exception
*/
public function checkHeader(BlockHeaderInterface $header)
{
return $this->check($header->getHash(), $header->getBits()->getInt());
}
/**
* @param BlockIndex $prevIndex
* @param BlockHeaderInterface $header
* @return BlockIndex
*/
public function makeIndex(BlockIndex $prevIndex, BlockHeaderInterface $header)
{
return new BlockIndex($header->getHash()->getHex(), $this->math->add($prevIndex->getHeight(), 1), $this->math->add($this->pow->getWork($header->getBits()), $prevIndex->getWork()), $header);
}
/**
* @param BlockHeaderInterface $header
* @return BlockIndexInterface|bool
*/
public function hasBlockTip(BlockHeaderInterface $header)
{
echo "CheckHashBlockTip - " . count($this->segments) . PHP_EOL;
foreach ($this->segments as $segment) {
/** @var BlockIndexInterface $segBlock */
$segBlock = $this->segmentBlock->offsetGet($segment);
if ($header->getPrevBlock()->equals($segBlock->getHash())) {
return $segBlock;
}
}
return false;
}
/**
* @param BufferInterface $hash
* @param BlockIndexInterface $prevIndex
* @param BlockHeaderInterface $header
* @return BlockIndex
*/
public function getNextIndex(BufferInterface $hash, BlockIndexInterface $prevIndex, BlockHeaderInterface $header)
{
return new BlockIndex($hash, $prevIndex->getHeight() + 1, $this->math->toString($this->math->add($this->proofOfWork->getWork($header->getBits()), gmp_init($prevIndex->getWork()))), $header);
}
/**
* @param BlockHeaderInterface $header
* @return \BitWasp\Buffertools\Buffer
*/
public function serialize(BlockHeaderInterface $header)
{
return $this->getTemplate()->write([$header->getVersion(), Buffer::hex($header->getPrevBlock()), Buffer::hex($header->getMerkleRoot()), $header->getTimestamp(), $header->getBits(), $header->getNonce()]);
}
/**
* @param Index\Blocks $blocks
* @param int $currentHeight
* @param BlockHeaderInterface $header
* @return bool
*/
public function scriptVerifyDerSig(Index\Blocks $blocks, $currentHeight, BlockHeaderInterface $header)
{
if ($this->math->cmp($header->getVersion(), 3) && $this->isSuperMajority(3, $currentHeight - 1, $blocks, $this->params->majorityEnforceBlockUpgrade())) {
return true;
}
return false;
}
/**
* Creates the Genesis block index
* @param BlockHeaderInterface $header
* @return bool
*/
public function createIndexGenesis(BlockHeaderInterface $header)
{
$stmtHeader = $this->dbh->prepare('INSERT INTO headerIndex (
hash, segment, height, work, version, prevBlock, merkleRoot, nBits, nTimestamp, nNonce
) VALUES (
:hash, :segment, :height, :work, :version, :prevBlock, :merkleRoot, :nBits, :nTimestamp, :nNonce
)
');
if ($stmtHeader->execute(array('hash' => $header->getHash()->getBinary(), 'segment' => 0, 'height' => 0, 'work' => 0, 'version' => $header->getVersion(), 'prevBlock' => $header->getPrevBlock()->getBinary(), 'merkleRoot' => $header->getMerkleRoot()->getBinary(), 'nBits' => $header->getBits(), 'nTimestamp' => $header->getTimestamp(), 'nNonce' => $header->getNonce()))) {
return true;
}
throw new \RuntimeException('Failed to update insert Genesis block index!');
}
/**
* @param BlockHeaderInterface $header
* @return string
*/
private function cacheIndexHeader(BlockHeaderInterface $header)
{
return "blkheight_" . $header->getBlockHash();
}
/**
* @param $timeFirstBlock
* @param BlockHeaderInterface $header
* @return mixed
*/
public function calculateWorkTimespan($timeFirstBlock, BlockHeaderInterface $header)
{
$timespan = $header->getTimestamp() - $timeFirstBlock;
$lowest = $this->params->powTargetTimespan() / 4;
$highest = $this->params->powTargetTimespan() * 4;
if ($timespan < $lowest) {
$timespan = $lowest;
}
if ($timespan > $highest) {
$timespan = $highest;
}
return $timespan;
}
/**
* @param BlockHeaderInterface $blk
* @return string
*/
private function cacheIndexBlk(BlockHeaderInterface $blk)
{
return $this->cacheIndex($blk->getBlockHash());
}
