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将 zCash 与 BitcoinJ 结合使用对我来说似乎是一个合理的进步，因为我需要为一个学术项目监控各种货币。目前，我使用来自 Dogecoin 开发人员的网络参数，使用zCash 以及用于比特币和莱特币的 BitcoinJ 运行一个完整节点。

鉴于 zCash 使用了大量比特币的代码库，我认为这可能是兼容的，但不幸的是我无法让它单独工作。

这是我在 ZcashMainNetParams 上的方法（它使用了很多来自 BitcoinJ 的 MainNetParams 类以及 zCashs chainparams.cpp）：

public class ZcashMainNetParams extends AbstractZcashMainNetParams {
    public static final int MAINNET_MAJORITY_WINDOW = 1000;
    public static final int MAINNET_MAJORITY_REJECT_BLOCK_OUTDATED = 950;
    public static final int MAINNET_MAJORITY_ENFORCE_BLOCK_UPGRADE = 750;

    public ZcashMainNetParams() {
        super();
        interval = INTERVAL;
        targetTimespan = TARGET_TIMESPAN;
        maxTarget = Utils.decodeCompactBits(0x1d00ffffL);
        dumpedPrivateKeyHeader = 128;
        addressHeader = 0;
        p2shHeader = 5;
        acceptableAddressCodes = new int[] { addressHeader, p2shHeader };
        port = 8233;
        packetMagic = 0xf9beb4d9 /* netmagic same as BTC ??? */;
        bip32HeaderPub = 0x0488B21E; //The 4 byte header that serializes in base58 to "xpub".
        bip32HeaderPriv = 0x0488ADE4; //The 4 byte header that serializes in base58 to "xprv"

        majorityEnforceBlockUpgrade = MAINNET_MAJORITY_ENFORCE_BLOCK_UPGRADE;
        majorityRejectBlockOutdated = MAINNET_MAJORITY_REJECT_BLOCK_OUTDATED;
        majorityWindow = MAINNET_MAJORITY_WINDOW;

        genesisBlock = createGenesis(this);
        id = ID_MAINNET;
        subsidyDecreaseBlockCount = 210000;
        spendableCoinbaseDepth = 100;
        String genesisHash = genesisBlock.getHashAsString();
        checkState(genesisHash.equals("00040fe8ec8471911baa1db1266ea15dd06b4a8a5c453883c000b031973dce08"),
                genesisHash); /* updated */

        // This contains (at a minimum) the blocks which are not BIP30 compliant. BIP30 changed how duplicate
        // transactions are handled. Duplicated transactions could occur in the case where a coinbase had the same
        // extraNonce and the same outputs but appeared at different heights, and greatly complicated re-org handling.
        // Having these here simplifies block connection logic considerably.
        checkpoints.put(2500, Sha256Hash.wrap("00000006dc968f600be11a86cbfbf7feb61c7577f45caced2e82b6d261d19744")) /* updated */;
        checkpoints.put(15000, Sha256Hash.wrap("00000000b6bc56656812a5b8dcad69d6ad4446dec23b5ec456c18641fb5381ba")) /* updated */;
        checkpoints.put(67500, Sha256Hash.wrap("000000006b366d2c1649a6ebb4787ac2b39c422f451880bc922e3a6fbd723616")) /* updated */;

        dnsSeeds = new String[] {
                "dnsseed.z.cash",    // Zcash
                "dnsseed.str4d.xyz", // @str4d
                "dnsseed.znodes.org" // @bitcartel
        };
    }

    private static AltcoinBlock createGenesis(NetworkParameters params) {
        AltcoinBlock genesisBlock = new AltcoinBlock(params, 4L);
        Transaction t = new Transaction(params);
        try {
            byte[] bytes = Hex.decode
                    ("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f");
            t.addInput(new TransactionInput(params, t, bytes));
            ByteArrayOutputStream scriptPubKeyBytes = new ByteArrayOutputStream();
            Script.writeBytes(scriptPubKeyBytes, Hex.decode
                    ("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"));
            scriptPubKeyBytes.write(ScriptOpCodes.OP_CHECKSIG);
            t.addOutput(new TransactionOutput(params, t, COIN.multiply(50), scriptPubKeyBytes.toByteArray()));
        } catch (Exception e) {
            // Cannot happen.
            throw new RuntimeException(e);
        }
        genesisBlock.addTransaction(t);
        genesisBlock.setTime(1477641360L);
        genesisBlock.setDifficultyTarget(504365040L);
        genesisBlock.setNonce(0x0000000000000000000000000000000000000000000000000000000000001257L);
        return genesisBlock;
    }

    private static ZcashMainNetParams instance;
    public static synchronized ZcashMainNetParams get() {
        if (instance == null) {
            instance = new ZcashMainNetParams();
        }
        return instance;
    }

    @Override
    public String getPaymentProtocolId() {
        return PAYMENT_PROTOCOL_ID_MAINNET;
    }
}

抽象类也被狗狗币开发者重用：

public abstract class AbstractZcashMainNetParams extends NetworkParameters {

    /**
     * Scheme part for Bitcoin URIs.
     */
    public static final String BITCOIN_SCHEME = "zcash";
    public static final int REWARD_HALVING_INTERVAL = 210000;

    private static final Logger log = LoggerFactory.getLogger(AbstractZcashMainNetParams.class);

    public AbstractZcashMainNetParams() {
        super();
    }

    /**
     * Checks if we are at a reward halving point.
     * @param height The height of the previous stored block
     * @return If this is a reward halving point
     */
    public final boolean isRewardHalvingPoint(final int height) {
        return ((height + 1) % REWARD_HALVING_INTERVAL) == 0;
    }

    /**
     * Checks if we are at a difficulty transition point.
     * @param height The height of the previous stored block
     * @return If this is a difficulty transition point
     */
    public final boolean isDifficultyTransitionPoint(final int height) {
        return ((height + 1) % this.getInterval()) == 0;
    }

    @Override
    public void checkDifficultyTransitions(final StoredBlock storedPrev, final Block nextBlock,
                                           final BlockStore blockStore) throws VerificationException, BlockStoreException {
        final Block prev = storedPrev.getHeader();

        // Is this supposed to be a difficulty transition point?
        if (!isDifficultyTransitionPoint(storedPrev.getHeight())) {

            // No ... so check the difficulty didn't actually change.
            if (nextBlock.getDifficultyTarget() != prev.getDifficultyTarget())
                throw new VerificationException("Unexpected change in difficulty at height " + storedPrev.getHeight() +
                        ": " + Long.toHexString(nextBlock.getDifficultyTarget()) + " vs " +
                        Long.toHexString(prev.getDifficultyTarget()));
            return;
        }

        // We need to find a block far back in the chain. It's OK that this is expensive because it only occurs every
        // two weeks after the initial block chain download.
        final Stopwatch watch = Stopwatch.createStarted();
        Sha256Hash hash = prev.getHash();
        StoredBlock cursor = null;
        final int interval = this.getInterval();
        for (int i = 0; i < interval; i++) {
            cursor = blockStore.get(hash);
            if (cursor == null) {
                // This should never happen. If it does, it means we are following an incorrect or busted chain.
                throw new VerificationException(
                        "Difficulty transition point but we did not find a way back to the last transition point. Not found: " + hash);
            }
            hash = cursor.getHeader().getPrevBlockHash();
        }
        checkState(cursor != null && isDifficultyTransitionPoint(cursor.getHeight() - 1),
                "Didn't arrive at a transition point.");
        watch.stop();
        if (watch.elapsed(TimeUnit.MILLISECONDS) > 50)
            log.info("Difficulty transition traversal took {}", watch);

        Block blockIntervalAgo = cursor.getHeader();
        int timespan = (int) (prev.getTimeSeconds() - blockIntervalAgo.getTimeSeconds());
        // Limit the adjustment step.
        final int targetTimespan = this.getTargetTimespan();
        if (timespan < targetTimespan / 4)
            timespan = targetTimespan / 4;
        if (timespan > targetTimespan * 4)
            timespan = targetTimespan * 4;

        BigInteger newTarget = Utils.decodeCompactBits(prev.getDifficultyTarget());
        newTarget = newTarget.multiply(BigInteger.valueOf(timespan));
        newTarget = newTarget.divide(BigInteger.valueOf(targetTimespan));

        if (newTarget.compareTo(this.getMaxTarget()) > 0) {
            log.info("Difficulty hit proof of work limit: {}", newTarget.toString(16));
            newTarget = this.getMaxTarget();
        }

        int accuracyBytes = (int) (nextBlock.getDifficultyTarget() >>> 24) - 3;
        long receivedTargetCompact = nextBlock.getDifficultyTarget();

        // The calculated difficulty is to a higher precision than received, so reduce here.
        BigInteger mask = BigInteger.valueOf(0xFFFFFFL).shiftLeft(accuracyBytes * 8);
        newTarget = newTarget.and(mask);
        long newTargetCompact = Utils.encodeCompactBits(newTarget);

        if (newTargetCompact != receivedTargetCompact)
            throw new VerificationException("Network provided difficulty bits do not match what was calculated: " +
                    Long.toHexString(newTargetCompact) + " vs " + Long.toHexString(receivedTargetCompact));
    }

    @Override
    public Coin getMaxMoney() {
        return MAX_MONEY;
    }

    @Override
    public Coin getMinNonDustOutput() {
        return Transaction.MIN_NONDUST_OUTPUT;
    }

    @Override
    public MonetaryFormat getMonetaryFormat() {
        return new MonetaryFormat();
    }

    @Override
    public int getProtocolVersionNum(final ProtocolVersion version) {
        return version.getBitcoinProtocolVersion();
    }

    @Override
    public BitcoinSerializer getSerializer(boolean parseRetain) {
        return new BitcoinSerializer(this, parseRetain);
    }

    @Override
    public String getUriScheme() {
        return BITCOIN_SCHEME;
    }

    @Override
    public boolean hasMaxMoney() {
        return true;
    }
}

我的问题基本上是创世块的生成。我无法用正确的哈希来伪造它。我相信这与我试图在zCash的 chainparams.cpp 中理解的交易有关。但是我的创世块有哈希 e88b11fd3581e170f86db9c574f65c0ada3216e126011ac968869f1b64ea4c4a而不是必需的 00040fe8ec8471911baa1db1266ea15dd06b4a8a5c453883c000b031973dce08

感谢您提供任何帮助，甚至包括一个合理的结论，即这是不可能的。

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1 回答 1

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tl;dr 您的代码没有考虑 Zcash 块头的格式，这与比特币和大多数山寨币都不同。您需要添加hashReservedandnSolution字段，并使用nNonce256 位而不是 32 位。

现在让我们假设您要做的就是解析 Zcash 区块链。为此，您需要进行两项更改：

  • 修改事务解析代码来处理我们的v2 事务（包含 JoinSplits）。
  • 修改块头以匹配我们的格式（你的问题是什么）。

Zcash 区块头是以下比特币的常规序列化：

int32_t nVersion;
uint256 hashPrevBlock;
uint256 hashMerkleRoot;
uint256 hashReserved;
uint32_t nTime;
uint32_t nBits;
uint256 nNonce;
std::vector<unsigned char> nSolution;

其中大多数的工作方式与比特币中的工作方式相同。您需要在 BitcoinJ 中实现的与比特币和大多数其他山寨币不同的是：

  • hashReserved- 一个简单的字段，目前始终为零（但不要假设）。
  • nNonce- 256 位而不是 32 位，但在其他方面具有相同的功能。
  • nSolution- 这是每个区块头中的 Equihash 解决方案。它被序列化为（比特币风格的）向量，因此您在技术上不需要知道如何解析它的内部；您可以只读取长度字段，然后读取那么多字节（当前为 1344，但不要假设这一点）。

实现上述内容将使您能够解析 Zcash 块头。如果您希望能够验证它们，您还需要完全解析nSolution，然后实现Equihash 验证器和难度调整算法。

为了完整nSolution起见，是 Equihash 解决方案索引的位连接，表示为字节数组。给定 Equihash 参数N和K，有2^K索引，每个长度(N/(K+1))+1位。对于 的当前参数(N, K) = (200, 9)，每个解决方案索引都是(200/(9+1))+1 = 21位，并且nSolution包含2^9 = 512索引。连接时总共有 10752 位，或 1344 字节。

资料来源：Zcash 工程师（我最初是从一个旧的 SE 帐户发布的）。

于 2018-02-13T02:38:32.487 回答