using System;
using System.Text;
using System.Collections.Generic;
+using System.IO;
+using System.Diagnostics.Contracts;
+using System.Numerics;
namespace Novacoin
{
+ [Serializable]
+ public class TransactionConstructorException : Exception
+ {
+ public TransactionConstructorException()
+ {
+ }
+
+ public TransactionConstructorException(string message)
+ : base(message)
+ {
+ }
+
+ public TransactionConstructorException(string message, Exception inner)
+ : base(message, inner)
+ {
+ }
+ }
+
/// <summary>
- /// Represents the transaction. Any transaction must provide one input and one output at least.
+ /// Represents the transaction.
/// </summary>
public class CTransaction
{
/// <summary>
+ /// One cent = 10000 satoshis.
+ /// </summary>
+ public const ulong nCent = 10000;
+
+ /// <summary>
+ /// One coin = 1000000 satoshis.
+ /// </summary>
+ public const ulong nCoin = 1000000;
+ /// <summary>
+ /// Sanity checking threshold.
+ /// </summary>
+ public const ulong nMaxMoney = 2000000000 * nCoin;
+
+ /// <summary>
+ /// Maximum transaction size is 250Kb
+ /// </summary>
+ public const uint nMaxTxSize = 250000;
+
+ /// <summary>
/// Version of transaction schema.
/// </summary>
- public uint nVersion = 1;
+ public uint nVersion;
/// <summary>
/// Transaction timestamp.
/// </summary>
- public uint nTime = 0;
+ public uint nTime;
/// <summary>
/// Array of transaction inputs
/// <summary>
/// Block height or timestamp when transaction is final
/// </summary>
- public uint nLockTime = 0;
+ public uint nLockTime;
/// <summary>
/// Initialize an empty instance
// Initialize empty input and output arrays. Please note that such
// configuration is not valid for real transaction, you have to supply
// at least one input and one output.
+ nVersion = 1;
+ nTime = 0;
vin = new CTxIn[0];
vout = new CTxOut[0];
+ nLockTime = 0;
}
/// <summary>
nLockTime = tx.nLockTime;
}
-
/// <summary>
- /// Parse byte sequence and initialize new instance of CTransaction
+ /// Attempts to execute all transaction scripts and validate the results.
/// </summary>
- /// <param name="txBytes">Byte sequence</param>
- public CTransaction(byte[] txBytes)
+ /// <returns>Checking result.</returns>
+ public bool VerifyScripts()
{
- var wBytes = new ByteQueue(txBytes);
+ if (IsCoinBase)
+ {
+ return true;
+ }
+
+ TxOutItem txOutCursor = null;
+ for (int i = 0; i < vin.Length; i++)
+ {
+ var outpoint = vin[i].prevout;
- nVersion = BitConverter.ToUInt32(wBytes.Get(4), 0);
- nTime = BitConverter.ToUInt32(wBytes.Get(4), 0);
+ if (!CBlockStore.Instance.GetTxOutCursor(outpoint, ref txOutCursor))
+ return false;
- int nInputs = (int)wBytes.GetVarInt();
- vin = new CTxIn[nInputs];
+ if (!ScriptCode.VerifyScript(vin[i].scriptSig, txOutCursor.scriptPubKey, this, i, (int)scriptflag.SCRIPT_VERIFY_P2SH, 0))
+ return false;
+ }
+
+ return true;
+ }
- for (int nCurrentInput = 0; nCurrentInput < nInputs; nCurrentInput++)
+ /// <summary>
+ /// Calculate amount of signature operations without trying to properly evaluate P2SH scripts.
+ /// </summary>
+ public uint LegacySigOpCount
+ {
+ get
{
- // Fill inputs array
- vin[nCurrentInput] = new CTxIn();
-
- vin[nCurrentInput].prevout = new COutPoint(wBytes.Get(36));
+ uint nSigOps = 0;
+ foreach (var txin in vin)
+ {
+ nSigOps += txin.scriptSig.GetSigOpCount(false);
+ }
+ foreach (var txout in vout)
+ {
+ nSigOps += txout.scriptPubKey.GetSigOpCount(false);
+ }
- int nScriptSigLen = (int)wBytes.GetVarInt();
- vin[nCurrentInput].scriptSig = new CScript(wBytes.Get(nScriptSigLen));
+ return nSigOps;
+ }
+ }
- vin[nCurrentInput].nSequence = BitConverter.ToUInt32(wBytes.Get(4), 0);
+ /// <summary>
+ /// Basic sanity checkings
+ /// </summary>
+ /// <returns>Checking result</returns>
+ public bool CheckTransaction()
+ {
+ if (Size > nMaxTxSize || vin.Length == 0 || vout.Length == 0)
+ {
+ return false;
}
- int nOutputs = (int)wBytes.GetVarInt();
- vout = new CTxOut[nOutputs];
+ // Check for empty or overflow output values
+ ulong nValueOut = 0;
+ for (int i = 0; i < vout.Length; i++)
+ {
+ CTxOut txout = vout[i];
+ if (txout.IsEmpty && !IsCoinBase && !IsCoinStake)
+ {
+ // Empty outputs aren't allowed for user transactions.
+ return false;
+ }
- for (int nCurrentOutput = 0; nCurrentOutput < nOutputs; nCurrentOutput++)
+ nValueOut += txout.nValue;
+ if (!MoneyRange(nValueOut))
+ {
+ return false;
+ }
+ }
+
+ // Check for duplicate inputs
+ var InOutPoints = new List<COutPoint>();
+ foreach (var txin in vin)
{
- // Fill outputs array
- vout[nCurrentOutput] = new CTxOut();
- vout[nCurrentOutput].nValue = BitConverter.ToInt64(wBytes.Get(8), 0);
+ if (InOutPoints.IndexOf(txin.prevout) != -1)
+ {
+ // Duplicate input.
+ return false;
+ }
+ InOutPoints.Add(txin.prevout);
+ }
- int nScriptPKLen = (int)wBytes.GetVarInt();
- vout[nCurrentOutput].scriptPubKey = new CScript(wBytes.Get(nScriptPKLen));
+ if (IsCoinBase)
+ {
+ if (vin[0].scriptSig.Size < 2 || vin[0].scriptSig.Size > 100)
+ {
+ // Script size is invalid
+ return false;
+ }
+ }
+ else
+ {
+ foreach (var txin in vin)
+ {
+ if (txin.prevout.IsNull)
+ {
+ // Null input in non-coinbase transaction.
+ return false;
+ }
+ }
}
- nLockTime = BitConverter.ToUInt32(wBytes.Get(4), 0);
+ return true;
+ }
+
+ public bool IsFinal(uint nBlockHeight = 0, uint nBlockTime = 0)
+ {
+ // Time based nLockTime
+ if (nLockTime == 0)
+ {
+ return true;
+ }
+ if (nBlockHeight == 0)
+ {
+ nBlockHeight = uint.MaxValue; // TODO: stupid stub here, should be best height instead.
+ }
+ if (nBlockTime == 0)
+ {
+ nBlockTime = NetInfo.GetAdjustedTime();
+ }
+ if (nLockTime < (nLockTime < NetInfo.nLockTimeThreshold ? nBlockHeight : nBlockTime))
+ {
+ return true;
+ }
+ foreach (var txin in vin)
+ {
+ if (!txin.IsFinal)
+ {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ /// <summary>
+ /// Parse byte sequence and initialize new instance of CTransaction
+ /// </summary>
+ /// <param name="txBytes">Byte sequence</param>
+ public CTransaction(byte[] txBytes)
+ {
+ try
+ {
+ var stream = new MemoryStream(txBytes);
+ var reader = new BinaryReader(stream);
+
+ nVersion = reader.ReadUInt32();
+ nTime = reader.ReadUInt32();
+
+ int nInputs = (int)VarInt.ReadVarInt(ref reader);
+ vin = new CTxIn[nInputs];
+
+ for (int nCurrentInput = 0; nCurrentInput < nInputs; nCurrentInput++)
+ {
+ // Fill inputs array
+ vin[nCurrentInput] = new CTxIn();
+
+ vin[nCurrentInput].prevout = new COutPoint(reader.ReadBytes(36));
+
+ int nScriptSigLen = (int)VarInt.ReadVarInt(ref reader);
+ vin[nCurrentInput].scriptSig = new CScript(reader.ReadBytes(nScriptSigLen));
+
+ vin[nCurrentInput].nSequence = reader.ReadUInt32();
+ }
+
+ int nOutputs = (int)VarInt.ReadVarInt(ref reader);
+ vout = new CTxOut[nOutputs];
+
+ for (int nCurrentOutput = 0; nCurrentOutput < nOutputs; nCurrentOutput++)
+ {
+ // Fill outputs array
+ vout[nCurrentOutput] = new CTxOut();
+ vout[nCurrentOutput].nValue = reader.ReadUInt64();
+
+ int nScriptPKLen = (int)VarInt.ReadVarInt(ref reader);
+ vout[nCurrentOutput].scriptPubKey = new CScript(reader.ReadBytes(nScriptPKLen));
+ }
+
+ nLockTime = reader.ReadUInt32();
+ }
+ catch (Exception e)
+ {
+ throw new TransactionConstructorException("Deserialization failed", e);
+ }
}
/// <summary>
/// </summary>
/// <param name="wTxBytes">Bytes sequence</param>
/// <returns>Transactions array</returns>
- public static CTransaction[] ReadTransactionsList(ref ByteQueue wTxBytes)
+ internal static CTransaction[] ReadTransactionsList(ref BinaryReader reader)
{
- // Read amount of transactions
- int nTransactions = (int)wTxBytes.GetVarInt();
- var tx = new CTransaction[nTransactions];
-
- for (int nTx = 0; nTx < nTransactions; nTx++)
+ try
{
- // Fill the transactions array
- tx[nTx] = new CTransaction();
+ // Read amount of transactions
+ int nTransactions = (int)VarInt.ReadVarInt(ref reader);
+ var tx = new CTransaction[nTransactions];
+
+ for (int nTx = 0; nTx < nTransactions; nTx++)
+ {
+ // Fill the transactions array
+ tx[nTx] = new CTransaction();
- tx[nTx].nVersion = BitConverter.ToUInt32(wTxBytes.Get(4), 0);
- tx[nTx].nTime = BitConverter.ToUInt32(wTxBytes.Get(4), 0);
+ tx[nTx].nVersion = reader.ReadUInt32();
+ tx[nTx].nTime = reader.ReadUInt32();
- // Inputs array
- tx[nTx].vin = CTxIn.ReadTxInList(ref wTxBytes);
+ // Inputs array
+ tx[nTx].vin = CTxIn.ReadTxInList(ref reader);
- // outputs array
- tx[nTx].vout = CTxOut.ReadTxOutList(ref wTxBytes);
+ // outputs array
+ tx[nTx].vout = CTxOut.ReadTxOutList(ref reader);
- tx[nTx].nLockTime = BitConverter.ToUInt32(wTxBytes.Get(4), 0);
- }
+ tx[nTx].nLockTime = reader.ReadUInt32();
+ }
+
+ return tx;
- return tx;
+ }
+ catch (Exception e)
+ {
+ throw new TransactionConstructorException("Deserialization failed", e);
+ }
}
public bool IsCoinBase
/// <summary>
/// Transaction hash
/// </summary>
- public Hash256 Hash
+ public uint256 Hash
+ {
+ get { return CryptoUtils.ComputeHash256(this); }
+ }
+
+ /// <summary>
+ /// Amount of novacoins spent by this transaction.
+ /// </summary>
+ public ulong nValueOut
{
- get { return Hash256.Compute256(this); }
+ get
+ {
+ ulong nValueOut = 0;
+ foreach (var txout in vout)
+ {
+ nValueOut += txout.nValue;
+ Contract.Assert(MoneyRange(txout.nValue) && MoneyRange(nValueOut));
+ }
+ return nValueOut;
+ }
}
/// <summary>
/// </summary>
public static implicit operator byte[] (CTransaction tx)
{
- var resultBytes = new List<byte>();
+ var stream = new MemoryStream();
+ var writer = new BinaryWriter(stream);
- resultBytes.AddRange(BitConverter.GetBytes(tx.nVersion));
- resultBytes.AddRange(BitConverter.GetBytes(tx.nTime));
- resultBytes.AddRange(VarInt.EncodeVarInt(tx.vin.LongLength));
+ writer.Write(tx.nVersion);
+ writer.Write(tx.nTime);
+ writer.Write(VarInt.EncodeVarInt(tx.vin.LongLength));
foreach (var input in tx.vin)
{
- resultBytes.AddRange((byte[])input);
+ writer.Write(input);
}
- resultBytes.AddRange(VarInt.EncodeVarInt(tx.vout.LongLength));
+ writer.Write(VarInt.EncodeVarInt(tx.vout.LongLength));
foreach (var output in tx.vout)
{
- resultBytes.AddRange((byte[])output);
+ writer.Write(output);
}
- resultBytes.AddRange(BitConverter.GetBytes(tx.nLockTime));
+ writer.Write(tx.nLockTime);
+ var resultBytes = stream.ToArray();
+ writer.Close();
- return resultBytes.ToArray();
+ return resultBytes;
}
public override string ToString()
foreach (var txin in vin)
{
- sb.AppendFormat(" {0},\n", txin.ToString());
+ sb.AppendFormat(" {0},\n", txin);
}
foreach (var txout in vout)
{
- sb.AppendFormat(" {0},\n", txout.ToString());
+ sb.AppendFormat(" {0},\n", txout);
}
sb.AppendFormat("\nnLockTime={0}\n)", nLockTime);
return sb.ToString();
}
- }
+
+ public static bool MoneyRange(ulong nValue) { return (nValue <= nMaxMoney); }
+
+ internal uint GetP2SHSigOpCount(Dictionary<COutPoint, TxOutItem> inputs)
+ {
+ throw new NotImplementedException();
+ }
+
+ internal ulong GetValueIn(Dictionary<COutPoint, TxOutItem> inputs)
+ {
+ throw new NotImplementedException();
+ }
+ }
}