Don't check proof-of-stake signature twice.

[NovacoinLibrary.git] / Novacoin / CBlock.cs

diff --git a/Novacoin/CBlock.cs b/Novacoin/CBlock.cs
index 6c10d6e..fba1387 100644 (file)
--- a/Novacoin/CBlock.cs
+++ b/Novacoin/CBlock.cs
@@ -21,7 +21,6 @@ using System.Text;
 using System.Collections.Generic;
 using System.Diagnostics.Contracts;
 using System.IO;
-using System.Numerics;
 
 namespace Novacoin
 {
@@ -165,7 +164,7 @@ namespace Novacoin
                     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;
@@ -180,7 +179,7 @@ namespace Novacoin
                 // Check proof-of-stake block signature
                 if (fCheckSig && !SignatureOK)
                 {
-                    return false;
+                    return false; // Proof-of-Stake signature checking failure.
                 }
 
                 if (!vtx[1].CheckTransaction())
@@ -270,7 +269,7 @@ namespace Novacoin
             return true;
         }
 
-        private bool CheckProofOfWork(uint256 hash, uint nBits)
+        private static bool CheckProofOfWork(uint256 hash, uint nBits)
         {
             uint256 nTarget = new uint256();
             nTarget.Compact = nBits;
@@ -382,18 +381,18 @@ namespace Novacoin
         /// <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;
             }
@@ -404,11 +403,11 @@ namespace Novacoin
         /// </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++)
             {
@@ -490,30 +489,29 @@ namespace Novacoin
             //
             // 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);
+            BigNum bnTarget = nTarget;
+            BigNum bnTargetLimit = NetInfo.nProofOfWorkLimit;
 
-            BigInteger bnLowerBound = CTransaction.nCent;
-            BigInteger bnUpperBound = bnSubsidyLimit;
+            BigNum bnSubsidyLimit = NetInfo.nMaxMintProofOfWork;
+            BigNum bnLowerBound = CTransaction.nCent;
+            BigNum bnUpperBound = bnSubsidyLimit;
 
             while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
             {
-                BigInteger bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+                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;
             }
 
-            ulong nSubsidy = (ulong)bnUpperBound;
+            ulong nSubsidy = bnUpperBound;
             nSubsidy = (nSubsidy / CTransaction.nCent) * CTransaction.nCent;
 
-
             return Math.Min(nSubsidy, NetInfo.nMaxMintProofOfWork) + nFees;
         }
 
@@ -525,23 +523,23 @@ namespace Novacoin
             {
                 // 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
+                BigNum 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));
+                BigNum bnTarget = nTarget;
+                BigNum bnTargetLimit = 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
+                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)
                 {
-                    BigInteger bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+                    BigNum bnMidValue = (bnLowerBound + bnUpperBound) / 2;
                     if (nTime < NetInfo.nStakeCurveSwitchTime)
                     {
                         //
@@ -575,7 +573,7 @@ namespace Novacoin
                         bnLowerBound = bnMidValue;
                 }
 
-                nRewardCoinYear = (ulong)bnUpperBound;
+                nRewardCoinYear = bnUpperBound;
                 nRewardCoinYear = Math.Min((nRewardCoinYear / CTransaction.nCent) * CTransaction.nCent, NetInfo.nMaxMintProofOfStake);
             }
             else