-\feffusing System;
+\feff/**
+ * Novacoin classes library
+ * Copyright (C) 2015 Alex D. (balthazar.ad@gmail.com)
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+using System;
using System.Text;
using System.Collections.Generic;
+using System.Diagnostics.Contracts;
namespace Novacoin
{
- /// <summary>
- /// Represents the block. Block consists of header, transaction array and header signature.
- /// </summary>
- public class CBlock
+ [Serializable]
+ public class BlockException : Exception
+ {
+ public BlockException()
+ {
+ }
+
+ public BlockException(string message)
+ : base(message)
+ {
+ }
+
+ public BlockException(string message, Exception inner)
+ : base(message, inner)
+ {
+ }
+ }
+
+ /// <summary>
+ /// Represents the block. Block consists of header, transaction array and header signature.
+ /// </summary>
+ public class CBlock
{
/// <summary>
/// Block header.
/// <summary>
/// Transactions array.
/// </summary>
- public CTransaction[] tx;
+ public CTransaction[] vtx;
- /// <summary>
- /// Block header signature.
- /// </summary>
- public byte[] signature;
+ /// <summary>
+ /// Block header signature.
+ /// </summary>
+ public byte[] signature = new byte[0];
+
+ /// <summary>
+ /// Copy constructor.
+ /// </summary>
+ /// <param name="b">CBlock instance.</param>
+ public CBlock(CBlock b)
+ {
+ header = new CBlockHeader(b.header);
+ vtx = new CTransaction[b.vtx.Length];
+
+ for (int i = 0; i < b.vtx.Length; i++)
+ {
+ vtx[i] = new CTransaction(b.vtx[i]);
+ }
+
+ signature = new byte[b.signature.Length];
+ b.signature.CopyTo(signature, 0);
+ }
/// <summary>
/// Parse byte sequence and initialize new block instance
/// </summary>
- /// <param name="blockBytes"></param>
- public CBlock (List<byte> blockBytes)
+ /// <param name="blockBytes">Bytes sequence.</param>
+ public CBlock (byte[] blockBytes)
{
- header = new CBlockHeader();
-
- WrappedList<byte> wBytes = new WrappedList<byte>(blockBytes);
+ try
+ {
+ ByteQueue wBytes = new ByteQueue(ref blockBytes);
- // Fill the block header fields
- header.nVersion = Interop.LEBytesToUInt32(wBytes.GetItems(4));
- header.prevHash = new Hash256(wBytes.GetItems(32));
- header.merkleRoot = new Hash256(wBytes.GetItems(32));
- header.nTime = Interop.LEBytesToUInt32(wBytes.GetItems(4));
- header.nBits = Interop.LEBytesToUInt32(wBytes.GetItems(4));
- header.nNonce = Interop.LEBytesToUInt32(wBytes.GetItems(4));
+ // Fill the block header fields
+ header = new CBlockHeader(wBytes.Get(80));
- // Parse transactions list
- tx = CTransaction.ReadTransactionsList(ref wBytes);
+ // Parse transactions list
+ vtx = CTransaction.ReadTransactionsList(ref wBytes);
- // Read block signature
- signature = wBytes.GetItems((int)VarInt.ReadVarInt(ref wBytes));
+ // Read block signature
+ signature = wBytes.Get((int)wBytes.GetVarInt());
+ }
+ catch (Exception e)
+ {
+ throw new BlockException("Deserialization failed", e);
+ }
}
+ public CBlock()
+ {
+ // Initialize empty array of transactions. Please note that such
+ // configuration is not valid real block since it has to provide
+ // at least one transaction.
+ vtx = new CTransaction[0];
+ }
+
+ public bool CheckBlock(bool fCheckPOW = true, bool fCheckMerkleRoot = true, bool fCheckSig = true)
+ {
+ var uniqueTX = new List<Hash256>(); // tx hashes
+ uint nSigOps = 0; // total sigops
+
+ // Basic sanity checkings
+ if (vtx.Length == 0 || Size > 1000000)
+ {
+ return false;
+ }
+
+ bool fProofOfStake = IsProofOfStake;
+
+ // First transaction must be coinbase, the rest must not be
+ if (!vtx[0].IsCoinBase)
+ {
+ return false;
+ }
+
+ if (!vtx[0].CheckTransaction())
+ {
+ return false;
+ }
+
+ uniqueTX.Add(vtx[0].Hash);
+ nSigOps += vtx[0].LegacySigOpCount;
+
+ if (fProofOfStake)
+ {
+ // Proof-of-STake related checkings. Note that we know here that 1st transactions is coinstake. We don't need
+ // check the type of 1st transaction because it's performed earlier by IsProofOfStake()
+
+ // nNonce must be zero for proof-of-stake blocks
+ if (header.nNonce != 0)
+ {
+ return false;
+ }
+
+ // Coinbase output should be empty if proof-of-stake block
+ if (vtx[0].vout.Length != 1 || !vtx[0].vout[0].IsEmpty)
+ {
+ return false;
+ }
+
+ // Check coinstake timestamp
+ if (header.nTime != vtx[1].nTime)
+ {
+ return false;
+ }
+
+ // Check proof-of-stake block signature
+ if (fCheckSig && !SignatureOK)
+ {
+ return false;
+ }
+
+ if (!vtx[1].CheckTransaction())
+ {
+ return false;
+ }
+
+ uniqueTX.Add(vtx[1].Hash);
+ nSigOps += vtx[1].LegacySigOpCount;
+ }
+ else
+ {
+ // Check proof of work matches claimed amount
+ if (fCheckPOW && !CheckProofOfWork(header.Hash, header.nBits))
+ {
+ return false;
+ }
+
+ // Check timestamp
+ if (header.nTime > NetUtils.FutureDrift(NetUtils.GetAdjustedTime()))
+ {
+ return false;
+ }
+
+ // Check coinbase timestamp
+ if (header.nTime < NetUtils.PastDrift(vtx[0].nTime))
+ {
+ return false;
+ }
+ }
+
+ // Iterate all transactions starting from second for proof-of-stake block
+ // or first for proof-of-work block
+ for (int i = fProofOfStake ? 2 : 1; i < vtx.Length; i++)
+ {
+ var tx = vtx[i];
+
+ // Reject coinbase transactions at non-zero index
+ if (tx.IsCoinBase)
+ {
+ return false;
+ }
+
+ // Reject coinstake transactions at index != 1
+ if (tx.IsCoinStake)
+ {
+ return false;
+ }
+
+ // Check transaction timestamp
+ if (header.nTime < tx.nTime)
+ {
+ return false;
+ }
+
+ // Check transaction consistency
+ if (!tx.CheckTransaction())
+ {
+ return false;
+ }
+
+ // Add transaction hash into list of unique transaction IDs
+ uniqueTX.Add(tx.Hash);
+
+ // Calculate sigops count
+ nSigOps += tx.LegacySigOpCount;
+ }
+
+ // Check for duplicate txids.
+ if (uniqueTX.Count != vtx.Length)
+ {
+ return false;
+ }
+
+ // Reject block if validation would consume too much resources.
+ if (nSigOps > 50000)
+ {
+ return false;
+ }
+
+ // Check merkle root
+ if (fCheckMerkleRoot && hashMerkleRoot != header.merkleRoot)
+ {
+ return false;
+ }
+
+ return true;
+ }
+
+ private bool CheckProofOfWork(ScryptHash256 hash, uint nBits)
+ {
+ // TODO: stub!
+
+ return true;
+ }
+
+ /// <summary>
+ /// Is this a Proof-of-Stake block?
+ /// </summary>
+ public bool IsProofOfStake
+ {
+ get
+ {
+ return (vtx.Length > 1 && vtx[1].IsCoinStake);
+ }
+ }
+
+ /// <summary>
+ /// Was this signed correctly?
+ /// </summary>
+ public bool SignatureOK
+ {
+ get
+ {
+ if (IsProofOfStake)
+ {
+ if (signature.Length == 0)
+ {
+ return false; // No signature
+ }
+
+ txnouttype whichType;
+ IList<byte[]> solutions;
+
+ if (!ScriptCode.Solver(vtx[1].vout[1].scriptPubKey, out whichType, out solutions))
+ {
+ return false; // No solutions found
+ }
+
+ if (whichType == txnouttype.TX_PUBKEY)
+ {
+ CPubKey pubkey;
+
+ try
+ {
+ pubkey = new CPubKey(solutions[0]);
+ }
+ catch (Exception)
+ {
+ return false; // Error while loading public key
+ }
+
+ return pubkey.VerifySignature(header.Hash, signature);
+ }
+ }
+ else
+ {
+ // Proof-of-Work blocks have no signature
+
+ return true;
+ }
+
+ return false;
+ }
+ }
+
+ /// <summary>
+ /// Get instance as sequence of bytes
+ /// </summary>
+ /// <returns>Byte sequence</returns>
+ public static implicit operator byte[] (CBlock b)
+ {
+ var r = new List<byte>();
+
+ r.AddRange((byte[])b.header);
+ r.AddRange(VarInt.EncodeVarInt(b.vtx.LongLength)); // transactions count
+
+ foreach (var tx in b.vtx)
+ {
+ r.AddRange((byte[])tx);
+ }
+
+ r.AddRange(VarInt.EncodeVarInt(b.signature.LongLength));
+ r.AddRange(b.signature);
+
+ return r.ToArray();
+ }
+
+ /// <summary>
+ /// Serialized size
+ /// </summary>
+ public int Size
+ {
+ get
+ {
+ int nSize = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
+
+ foreach (var tx in vtx)
+ {
+ nSize += tx.Size;
+ }
+
+ nSize += VarInt.GetEncodedSize(signature.Length) + signature.Length;
+
+ return nSize;
+ }
+ }
+
+ /// <summary>
+ /// Get transaction offset inside block.
+ /// </summary>
+ /// <param name="nTx">Transaction index.</param>
+ /// <returns>Offset in bytes from the beginning of block header.</returns>
+ public int 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
+
+ for (int i = 0; i < nTx; i++)
+ {
+ nOffset += vtx[i].Size;
+ }
+
+ return nOffset;
+ }
+
+ /// <summary>
+ /// Merkle root
+ /// </summary>
+ public Hash256 hashMerkleRoot
+ {
+ get {
+
+ var merkleTree = new List<byte>();
+
+ foreach (var tx in vtx)
+ {
+ merkleTree.AddRange(Hash256.ComputeRaw256(tx));
+ }
+
+ int levelOffset = 0;
+ for (int nLevelSize = vtx.Length; nLevelSize > 1; nLevelSize = (nLevelSize + 1) / 2)
+ {
+ for (int nLeft = 0; nLeft < nLevelSize; nLeft += 2)
+ {
+ int nRight = Math.Min(nLeft + 1, nLevelSize - 1);
+
+ 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));
+ }
+ levelOffset += nLevelSize;
+ }
+
+ return (merkleTree.Count == 0) ? new Hash256() : new Hash256(merkleTree.GetRange(merkleTree.Count-32, 32).ToArray());
+ }
+ }
+
public override string ToString()
{
- StringBuilder sb = new StringBuilder();
+ var sb = new StringBuilder();
sb.AppendFormat("CBlock(\n header={0},\n", header.ToString());
- foreach(CTransaction t in tx)
+ foreach(var tx in vtx)
{
- sb.AppendFormat("{0}, \n", t.ToString());
+ sb.AppendFormat("{0}", tx.ToString());
}
- sb.AppendFormat("signature={0})\n", Interop.ToHex(signature));
-
+ if (IsProofOfStake)
+ {
+ sb.AppendFormat(", signature={0}, signatureOK={1}\n", Interop.ToHex(signature), SignatureOK);
+ }
- // TODO
+ sb.Append(")");
+
return sb.ToString();
}
}
git://git.novaco.in / NovacoinLibrary.git / blobdiff