/// </summary>
public class CBlock
{
+ /// <summary>
+ /// Maximum block size is 1Mb.
+ /// </summary>
+ public const uint nMaxBlockSize = 1000000;
+
+ /// <summary>
+ /// Sanity threshold for amount of sigops.
+ /// </summary>
+ public const uint nMaxSigOps = 20000;
+
/// <summary>
/// Block header.
/// </summary>
{
try
{
- ByteQueue wBytes = new ByteQueue(ref blockBytes);
+ var stream = new MemoryStream(blockBytes);
+ var reader = new BinaryReader(stream);
// Fill the block header fields
- header = new CBlockHeader(wBytes.Get(80));
+ header = new CBlockHeader(ref reader);
// Parse transactions list
- vtx = CTransaction.ReadTransactionsList(ref wBytes);
+ vtx = CTransaction.ReadTransactionsList(ref reader);
// Read block signature
- signature = wBytes.Get((int)wBytes.GetVarInt());
+ signature = reader.ReadBytes((int)VarInt.ReadVarInt(ref reader));
+
+ reader.Close();
}
catch (Exception e)
{
public bool CheckBlock(bool fCheckPOW = true, bool fCheckMerkleRoot = true, bool fCheckSig = true)
{
- var uniqueTX = new List<Hash256>(); // tx hashes
+ var uniqueTX = new List<uint256>(); // tx hashes
uint nSigOps = 0; // total sigops
// Basic sanity checkings
- if (vtx.Length == 0 || Size > 1000000)
+ if (vtx.Length == 0 || Size > nMaxBlockSize)
{
return false;
}
return false;
}
- // Coinbase output should be empty if proof-of-stake block
+ // Coinbase output must be empty if proof-of-stake block
if (vtx[0].vout.Length != 1 || !vtx[0].vout[0].IsEmpty)
{
return false;
// Check proof-of-stake block signature
if (fCheckSig && !SignatureOK)
{
- return false;
+ return false; // Proof-of-Stake signature checking failure.
}
if (!vtx[1].CheckTransaction())
}
// Check timestamp
- if (header.nTime > NetUtils.FutureDrift(NetUtils.GetAdjustedTime()))
+ if (header.nTime > NetInfo.FutureDrift(NetInfo.GetAdjustedTime()))
{
return false;
}
// Check coinbase timestamp
- if (header.nTime < NetUtils.PastDrift(vtx[0].nTime))
+ if (header.nTime < NetInfo.PastDrift(vtx[0].nTime))
{
return false;
}
}
// Reject block if validation would consume too much resources.
- if (nSigOps > 50000)
+ if (nSigOps > nMaxSigOps)
{
return false;
}
return true;
}
- private bool CheckProofOfWork(ScryptHash256 hash, uint nBits)
+ private static bool CheckProofOfWork(uint256 hash, uint nBits)
{
- // TODO: stub!
+ uint256 nTarget = new uint256();
+ nTarget.Compact = nBits;
+
+ // Check range
+ if (nTarget > NetInfo.nProofOfWorkLimit)
+ {
+ // nBits below minimum work
+ return false;
+ }
+
+ // Check proof of work matches claimed amount
+ if (hash > nTarget)
+ {
+ // hash doesn't match nBits
+ return false;
+ }
return true;
}
/// <summary>
/// Serialized size
/// </summary>
- public int Size
+ public uint Size
{
get
{
- int nSize = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
+ uint nSize = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
foreach (var tx in vtx)
{
nSize += tx.Size;
}
- nSize += VarInt.GetEncodedSize(signature.Length) + signature.Length;
+ nSize += VarInt.GetEncodedSize(signature.Length) + (uint)signature.Length;
return nSize;
}
/// </summary>
/// <param name="nTx">Transaction index.</param>
/// <returns>Offset in bytes from the beginning of block header.</returns>
- public int GetTxOffset(int nTx)
+ public uint GetTxOffset(int nTx)
{
Contract.Requires<ArgumentException>(nTx >= 0 && nTx < vtx.Length, "Transaction index you've specified is incorrect.");
- int nOffset = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
+ uint nOffset = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
for (int i = 0; i < nTx; i++)
{
/// <summary>
/// Merkle root
/// </summary>
- public Hash256 hashMerkleRoot
+ public uint256 hashMerkleRoot
{
get {
foreach (var tx in vtx)
{
- merkleTree.AddRange(Hash256.ComputeRaw256(tx));
+ merkleTree.AddRange(CryptoUtils.ComputeHash256(tx));
}
int levelOffset = 0;
var left = merkleTree.GetRange((levelOffset + nLeft) * 32, 32).ToArray();
var right = merkleTree.GetRange((levelOffset + nRight) * 32, 32).ToArray();
- merkleTree.AddRange(Hash256.ComputeRaw256(ref left, ref right));
+ merkleTree.AddRange(CryptoUtils.ComputeHash256(ref left, ref right));
}
levelOffset += nLevelSize;
}
- return (merkleTree.Count == 0) ? new Hash256() : new Hash256(merkleTree.GetRange(merkleTree.Count-32, 32).ToArray());
+ return (merkleTree.Count == 0) ? 0 : (uint256)merkleTree.GetRange(merkleTree.Count-32, 32).ToArray();
}
}
return sb.ToString();
}
- }
+
+ /// <summary>
+ /// Calculate proof-of-work reward.
+ /// </summary>
+ /// <param name="nBits">Packed difficulty representation.</param>
+ /// <param name="nFees">Amount of fees.</param>
+ /// <returns>Reward value.</returns>
+ public static long GetProofOfWorkReward(uint nBits, long nFees)
+ {
+ // NovaCoin: subsidy is cut in half every 64x multiply of PoW difficulty
+ // A reasonably continuous curve is used to avoid shock to market
+ // (nSubsidyLimit / nSubsidy) ** 6 == bnProofOfWorkLimit / bnTarget
+ //
+ // Human readable form:
+ //
+ // nSubsidy = 100 / (diff ^ 1/6)
+ //
+ // Please note that we're using bisection to find an approximate solutuion
+
+
+ uint256 nTarget = 0;
+ nTarget.Compact = nBits;
+
+ BigNum bnTarget = nTarget;
+ BigNum bnTargetLimit = NetInfo.nProofOfWorkLimit;
+
+ BigNum bnSubsidyLimit = NetInfo.nMaxMintProofOfWork;
+ BigNum bnLowerBound = CTransaction.nCent;
+ BigNum bnUpperBound = bnSubsidyLimit;
+
+ while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
+ {
+ BigNum bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+ if (bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnTargetLimit > bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnTarget)
+ bnUpperBound = bnMidValue;
+ else
+ bnLowerBound = bnMidValue;
+ }
+
+ long nSubsidy = bnUpperBound;
+ nSubsidy = (nSubsidy / CTransaction.nCent) * CTransaction.nCent;
+
+ return Math.Min(nSubsidy, NetInfo.nMaxMintProofOfWork) + nFees;
+ }
+
+ public static long GetProofOfStakeReward(long nCoinAge, uint nBits, uint nTime)
+ {
+ // Second stage of emission process is mostly PoS-based.
+
+ long nRewardCoinYear, nSubsidy, nSubsidyLimit = 10 * CTransaction.nCoin;
+ // Base stake mint rate, 100% year interest
+ BigNum bnRewardCoinYearLimit = NetInfo.nMaxMintProofOfStake;
+
+ uint256 nTarget = 0;
+ nTarget.Compact = nBits;
+
+ BigNum bnTarget = nTarget;
+ BigNum bnTargetLimit = NetInfo.GetProofOfStakeLimit(0, nTime);
+
+ // A reasonably continuous curve is used to avoid shock to market
+
+ BigNum bnLowerBound = CTransaction.nCent, // Lower interest bound is 1% per year
+ bnUpperBound = bnRewardCoinYearLimit, // Upper interest bound is 100% per year
+ bnMidPart, bnRewardPart;
+
+ while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
+ {
+ BigNum bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+
+ // Reward for coin-year is cut in half every 8x multiply of PoS difficulty
+ //
+ // (nRewardCoinYearLimit / nRewardCoinYear) ** 3 == bnProofOfStakeLimit / bnTarget
+ //
+ // Human readable form: nRewardCoinYear = 1 / (posdiff ^ 1/3)
+
+ bnMidPart = bnMidValue * bnMidValue * bnMidValue;
+ bnRewardPart = bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit;
+
+ if (bnMidPart * bnTargetLimit > bnRewardPart * bnTarget)
+ {
+ bnUpperBound = bnMidValue;
+ }
+ else
+ {
+ bnLowerBound = bnMidValue;
+ }
+ }
+
+ nRewardCoinYear = bnUpperBound;
+ nRewardCoinYear = Math.Min((nRewardCoinYear / CTransaction.nCent) * CTransaction.nCent, NetInfo.nMaxMintProofOfStake);
+
+ nSubsidy = nCoinAge * nRewardCoinYear * 33 / (365 * 33 + 8);
+
+ // Set reasonable reward limit for large inputs
+ // This will stimulate large holders to use smaller inputs, that's good
+ // for the network protection
+ return Math.Min(nSubsidy, nSubsidyLimit);
+ }
+
+ public Tuple<COutPoint, uint> ProofOfStake
+ {
+ get { return IsProofOfStake ? new Tuple<COutPoint, uint>(vtx[1].vin[0].prevout, vtx[1].nTime) : new Tuple<COutPoint, uint>(new COutPoint(), 0); }
+ }
+
+}
}
git://git.novaco.in / NovacoinLibrary.git / blobdiff