using System.Text;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
+using System.IO;
+using System.Numerics;
namespace Novacoin
{
/// </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;
}
}
// 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 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;
}
/// <returns>Byte sequence</returns>
public static implicit operator byte[] (CBlock b)
{
- var r = new List<byte>();
+ var stream = new MemoryStream();
+ var writer = new BinaryWriter(stream);
- r.AddRange((byte[])b.header);
- r.AddRange(VarInt.EncodeVarInt(b.vtx.LongLength)); // transactions count
+ writer.Write(b.header);
+ writer.Write(VarInt.EncodeVarInt(b.vtx.LongLength));
foreach (var tx in b.vtx)
{
- r.AddRange((byte[])tx);
+ writer.Write(tx);
}
- r.AddRange(VarInt.EncodeVarInt(b.signature.LongLength));
- r.AddRange(b.signature);
+ writer.Write(VarInt.EncodeVarInt(b.signature.LongLength));
+ writer.Write(b.signature);
+
+ var resultBytes = stream.ToArray();
- return r.ToArray();
+ writer.Close();
+
+ return resultBytes;
}
/// <summary>
/// <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 ulong GetProofOfWorkReward(uint nBits, ulong 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
+
+ BigInteger bnSubsidyLimit = NetInfo.nMaxMintProofOfWork;
+
+ uint256 nTarget = 0;
+ nTarget.Compact = nBits;
+
+ BigInteger bnTarget = new BigInteger(nTarget);
+ BigInteger bnTargetLimit = new BigInteger(NetInfo.nProofOfWorkLimit);
+
+ BigInteger bnLowerBound = CTransaction.nCent;
+ BigInteger bnUpperBound = bnSubsidyLimit;
+
+ while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
+ {
+ BigInteger bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+ if (bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnTargetLimit > bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnTarget)
+ bnUpperBound = bnMidValue;
+ else
+ bnLowerBound = bnMidValue;
+ }
+
+ ulong nSubsidy = (ulong)bnUpperBound;
+ nSubsidy = (nSubsidy / CTransaction.nCent) * CTransaction.nCent;
+
+
+ return Math.Min(nSubsidy, NetInfo.nMaxMintProofOfWork) + nFees;
+ }
+ }
}
git://git.novaco.in / NovacoinLibrary.git / blobdiff