X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=Novacoin%2FCBlock.cs;h=6c10d6e385a7bdba7f13c640ad41b4aa82528326;hb=bc970ef64962497a7e29d49c9d8b1f7945eb77c0;hp=d8d7a758f0670ab4484bb916323452ec1162ea5d;hpb=031d9e2250687721838d86647625a6c949f91de6;p=NovacoinLibrary.git diff --git a/Novacoin/CBlock.cs b/Novacoin/CBlock.cs index d8d7a75..6c10d6e 100644 --- a/Novacoin/CBlock.cs +++ b/Novacoin/CBlock.cs @@ -21,6 +21,7 @@ using System.Text; using System.Collections.Generic; using System.Diagnostics.Contracts; using System.IO; +using System.Numerics; namespace Novacoin { @@ -47,6 +48,16 @@ namespace Novacoin /// public class CBlock { + /// + /// Maximum block size is 1Mb. + /// + public const uint nMaxBlockSize = 1000000; + + /// + /// Sanity threshold for amount of sigops. + /// + public const uint nMaxSigOps = 20000; + /// /// Block header. /// @@ -118,11 +129,11 @@ namespace Novacoin public bool CheckBlock(bool fCheckPOW = true, bool fCheckMerkleRoot = true, bool fCheckSig = true) { - var uniqueTX = new List(); // tx hashes + var uniqueTX = new List(); // tx hashes uint nSigOps = 0; // total sigops // Basic sanity checkings - if (vtx.Length == 0 || Size > 1000000) + if (vtx.Length == 0 || Size > nMaxBlockSize) { return false; } @@ -189,13 +200,13 @@ namespace Novacoin } // 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; } @@ -245,7 +256,7 @@ namespace Novacoin } // Reject block if validation would consume too much resources. - if (nSigOps > 50000) + if (nSigOps > nMaxSigOps) { return false; } @@ -259,9 +270,24 @@ namespace Novacoin 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; } @@ -395,7 +421,7 @@ namespace Novacoin /// /// Merkle root /// - public Hash256 hashMerkleRoot + public uint256 hashMerkleRoot { get { @@ -403,7 +429,7 @@ namespace Novacoin foreach (var tx in vtx) { - merkleTree.AddRange(Hash256.ComputeRaw256(tx)); + merkleTree.AddRange(CryptoUtils.ComputeHash256(tx)); } int levelOffset = 0; @@ -416,12 +442,12 @@ namespace Novacoin 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(); } } @@ -445,6 +471,131 @@ namespace Novacoin return sb.ToString(); } - } + + /// + /// Calculate proof-of-work reward. + /// + /// Packed difficulty representation. + /// Amount of fees. + /// Reward value. + 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; + } + + public static ulong GetProofOfStakeReward(ulong nCoinAge, uint nBits, uint nTime) + { + ulong nRewardCoinYear, nSubsidy, nSubsidyLimit = 10 * CTransaction.nCoin; + + if (nTime > NetInfo.nDynamicStakeRewardTime) + { + // Stage 2 of emission process is PoS-based. It will be active on mainNet since 20 Jun 2013. + + BigInteger bnRewardCoinYearLimit = NetInfo.nMaxMintProofOfStake; // Base stake mint rate, 100% year interest + + uint256 nTarget = 0; + nTarget.Compact = nBits; + + BigInteger bnTarget = new BigInteger(nTarget); + BigInteger bnTargetLimit = new BigInteger(NetInfo.GetProofOfStakeLimit(0, nTime)); + + // NovaCoin: A reasonably continuous curve is used to avoid shock to market + + BigInteger 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) + { + BigInteger bnMidValue = (bnLowerBound + bnUpperBound) / 2; + if (nTime < NetInfo.nStakeCurveSwitchTime) + { + // + // Until 20 Oct 2013: reward for coin-year is cut in half every 64x multiply of PoS difficulty + // + // (nRewardCoinYearLimit / nRewardCoinYear) ** 6 == bnProofOfStakeLimit / bnTarget + // + // Human readable form: nRewardCoinYear = 1 / (posdiff ^ 1/6) + // + + bnMidPart = bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue; + bnRewardPart = bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit; + } + else + { + // + // Since 20 Oct 2013: 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 = (ulong)bnUpperBound; + nRewardCoinYear = Math.Min((nRewardCoinYear / CTransaction.nCent) * CTransaction.nCent, NetInfo.nMaxMintProofOfStake); + } + else + { + // Old creation amount per coin-year, 5% fixed stake mint rate + nRewardCoinYear = 5 * CTransaction.nCent; + } + + nSubsidy = nCoinAge * nRewardCoinYear * 33 / (365 * 33 + 8); + + // Set reasonable reward limit for large inputs since 20 Oct 2013 + // + // This will stimulate large holders to use smaller inputs, that's good for the network protection + if (NetInfo.nStakeCurveSwitchTime < nTime) + { + nSubsidy = Math.Min(nSubsidy, nSubsidyLimit); + } + + return nSubsidy; + } + } }