-\feffusing System;
-using System.Text;
+\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.
-using System.Collections;
+ * 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.Linq;
+using System.Text;
using System.Collections.Generic;
+using System.Diagnostics.Contracts;
namespace Novacoin
{
- public class CScript : List<byte>
+ /// <summary>
+ /// Representation of script code
+ /// </summary>
+ public class CScript
{
+ private List<byte> codeBytes;
+
+ /// <summary>
+ /// Initializes an empty instance of CScript
+ /// </summary>
public CScript ()
{
+ codeBytes = new List<byte>();
}
+ /// <summary>
+ /// Initializes new instance of CScript and fills it with supplied bytes
+ /// </summary>
+ /// <param name="bytes">Enumerator interface for byte sequence</param>
+ public CScript(byte[] bytes)
+ {
+ codeBytes = new List<byte>(bytes);
+ }
+
+ /// <summary>
+ /// Return a new instance of ByteQueue object for current code bytes
+ /// </summary>
+ /// <returns></returns>
+ public InstructionQueue GetInstructionQueue()
+ {
+ return new InstructionQueue(ref codeBytes);
+ }
+
+ /// <summary>
+ /// Adds specified operation to instruction list
+ /// </summary>
+ /// <param name="opcode"></param>
+ public void AddInstruction(instruction opcode)
+ {
+ Contract.Requires<ArgumentException>(opcode >= instruction.OP_0 && opcode <= instruction.OP_INVALIDOPCODE, "Invalid instruction.");
+
+ codeBytes.Add((byte)opcode);
+ }
+
+ /// <summary>
+ /// Adds hash to instruction list.
+ /// New items are added in this format:
+ /// hash_length_byte hash_bytes
+ /// </summary>
+ /// <param name="hash">Hash160 instance</param>
+ public void AddHash(uint160 hash)
+ {
+ codeBytes.Add((byte)hash.Size);
+ codeBytes.AddRange((byte[])hash);
+ }
+
+ /// <summary>
+ /// Adds hash to instruction list.
+ /// New items are added in this format:
+ /// hash_length_byte hash_bytes
+ /// </summary>
+ /// <param name="hash">Hash256 instance</param>
+ public void AddHash(uint256 hash)
+ {
+ codeBytes.Add((byte)hash.Size);
+ codeBytes.AddRange((byte[])hash);
+ }
+
+ /// <summary>
+ /// Create new OP_PUSHDATAn operator and add it to instruction list
+ /// </summary>
+ /// <param name="dataBytes">Set of data bytes</param>
+ public void PushData(byte[] dataBytes)
+ {
+ var nCount = dataBytes.LongLength;
+
+ if (nCount < (int)instruction.OP_PUSHDATA1)
+ {
+ // OP_0 and OP_FALSE
+ codeBytes.Add((byte)nCount);
+ }
+ else if (nCount < 0xff)
+ {
+ // OP_PUSHDATA1 0x01 [0x5a]
+ codeBytes.Add((byte)instruction.OP_PUSHDATA1);
+ codeBytes.Add((byte)nCount);
+ }
+ else if (nCount < 0xffff)
+ {
+ // OP_PUSHDATA1 0x01 0x00 [0x5a]
+ codeBytes.Add((byte)instruction.OP_PUSHDATA2);
+
+ var szBytes = BitConverter.GetBytes((ushort)nCount);
+ codeBytes.AddRange(szBytes);
+ }
+ else if (nCount < 0xffffffff)
+ {
+ // OP_PUSHDATA1 0x01 0x00 0x00 0x00 [0x5a]
+ codeBytes.Add((byte)instruction.OP_PUSHDATA4);
+
+ var szBytes = BitConverter.GetBytes((uint)nCount);
+ codeBytes.AddRange(szBytes);
+ }
+
+ // Add data bytes
+ codeBytes.AddRange(dataBytes);
+ }
+
+ /// <summary>
+ /// Just insert data array without including any prefixes. Please make sure that you know what you're doing,
+ /// it is recommended to use AddInstruction, AddHash or PushData instead.
+ /// </summary>
+ /// <param name="dataBytes">Data bytes</param>
+ public void AddRawData(byte[] dataBytes)
+ {
+ // Add data bytes
+ codeBytes.AddRange(dataBytes);
+ }
+
+ /// <summary>
+ /// Scan pushed data bytes for pattern and, in case of exact match, remove it.
+ /// </summary>
+ /// <param name="pattern">Pattern sequence</param>
+ /// <returns>Matches count</returns>
+ public int RemovePattern(byte[] pattern)
+ {
+ // There is no sense to continue if pattern is empty or longer than script itself
+ if (pattern.Length == 0 || pattern.Length > codeBytes.Count)
+ {
+ return 0;
+ }
+
+ var count = 0;
+ var bq1 = new InstructionQueue(ref codeBytes);
+
+ byte[] pushData;
+ instruction opcode;
+
+ var newScript = new CScript();
+
+ while (ScriptCode.GetOp(ref bq1, out opcode, out pushData))
+ {
+ if (pushData.Length == 0)
+ {
+ // No data, put instruction on its place
+ newScript.AddInstruction(opcode);
+ }
+ else if (!pushData.SequenceEqual(pattern))
+ {
+ // No match, create push operator
+ newScript.PushData(pushData);
+ }
+ else
+ {
+ count++; // match
+ }
+ }
+
+ if (count > 0)
+ {
+ // Replace current script if any matches were found
+ codeBytes = newScript.codeBytes;
+ }
+
+ return count;
+ }
+
+ /// <summary>
+ /// Scan script for specific instruction and remove it if there are some matches.
+ /// </summary>
+ /// <param name="op">Instruction</param>
+ /// <returns>Matches count</returns>
+ public int RemoveInstruction(instruction op)
+ {
+ byte[] pushData;
+ instruction opcode;
+
+ var count = 0;
+ var newScript = new CScript();
+ var bq1 = new InstructionQueue(ref codeBytes);
+
+ while (ScriptCode.GetOp(ref bq1, out opcode, out pushData))
+ {
+ if (pushData.Length != 0 && op != opcode)
+ {
+ // If instruction didn't match then push its data again
+ newScript.PushData(pushData);
+ }
+ else if (Enum.IsDefined(typeof(instruction), op) && op != opcode)
+ {
+ // Instruction didn't match
+ newScript.AddInstruction(opcode);
+ }
+ else
+ {
+ count++; // match
+ }
+ }
+
+ if (count > 0)
+ {
+ // Replace current script if any matches were found
+ codeBytes = newScript.codeBytes;
+ }
+
+ return count;
+ }
+
+ /// <summary>
+ /// Is it true that script doesn't contain anything except push value operations?
+ /// </summary>
+ public bool IsPushOnly
+ {
+ get
+ {
+ var wCodeBytes = new InstructionQueue(ref codeBytes);
+
+ instruction opcode; // Current instruction
+ byte[] pushArgs; // OP_PUSHDATAn argument
+
+ // Scan instructions sequence
+ while (ScriptCode.GetOp(ref wCodeBytes, out opcode, out pushArgs))
+ {
+ if (opcode > instruction.OP_16)
+ {
+ // We don't allow control instructions here
+ return false;
+ }
+ }
+
+ return true;
+ }
+ }
+ /// <summary>
+ /// Is it true that script doesn't contain non-canonical push operations?
+ /// </summary>
+ public bool HasOnlyCanonicalPushes
+ {
+ get
+ {
+ var wCodeBytes = new InstructionQueue(ref codeBytes);
-
+ byte[] pushArgs; // OP_PUSHDATAn argument
+ instruction opcode; // Current instruction
+ // Scan instructions sequence
+ while (ScriptCode.GetOp(ref wCodeBytes, out opcode, out pushArgs))
+ {
+ var data = pushArgs;
+
+ if (opcode < instruction.OP_PUSHDATA1 && opcode > instruction.OP_0 && (data.Length == 1 && data[0] <= 16))
+ {
+ // Could have used an OP_n code, rather than a 1-byte push.
+ return false;
+ }
+ if (opcode == instruction.OP_PUSHDATA1 && data.Length < (int)instruction.OP_PUSHDATA1)
+ {
+ // Could have used a normal n-byte push, rather than OP_PUSHDATA1.
+ return false;
+ }
+ if (opcode == instruction.OP_PUSHDATA2 && data.Length <= 0xFF)
+ {
+ // Could have used an OP_PUSHDATA1.
+ return false;
+ }
+ if (opcode == instruction.OP_PUSHDATA4 && data.LongLength <= 0xFFFF)
+ {
+ // Could have used an OP_PUSHDATA2.
+ return false;
+ }
+ }
+
+ return true;
+ }
+ }
+
+ /// <summary>
+ /// Quick test for pay-to-script-hash CScripts
+ /// </summary>
+ public bool IsPayToScriptHash
+ {
+ get
+ {
+ // Sender provides redeem script hash, receiver provides signature list and redeem script
+ // OP_HASH160 20 [20 byte hash] OP_EQUAL
+ return (codeBytes.Count() == 23 &&
+ codeBytes[0] == (byte)instruction.OP_HASH160 &&
+ codeBytes[1] == 0x14 && // 20 bytes hash length prefix
+ codeBytes[22] == (byte)instruction.OP_EQUAL);
+ }
+ }
+
+ /// <summary>
+ /// Quick test for pay-to-pubkeyhash CScripts
+ /// </summary>
+ public bool IsPayToPubKeyHash
+ {
+ get
+ {
+ // Sender provides hash of pubkey, receiver provides signature and pubkey
+ // OP_DUP OP_HASH160 20 [20 byte hash] OP_EQUALVERIFY OP_CHECKSIG
+ return (codeBytes.Count == 25 &&
+ codeBytes[0] == (byte)instruction.OP_DUP &&
+ codeBytes[1] == (byte)instruction.OP_HASH160 &&
+ codeBytes[2] == 0x14 && // 20 bytes hash length prefix
+ codeBytes[23] == (byte)instruction.OP_EQUALVERIFY &&
+ codeBytes[24] == (byte)instruction.OP_CHECKSIG);
+ }
+ }
+
+ /// <summary>
+ /// Quick test for Null destination
+ /// </summary>
+ public bool IsNull
+ {
+ get { return codeBytes.Count == 0; }
+ }
+
+ /// <summary>
+ /// Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
+ /// as 20 sigops. With pay-to-script-hash, that changed:
+ /// CHECKMULTISIGs serialized in scriptSigs are
+ /// counted more accurately, assuming they are of the form
+ /// ... OP_N CHECKMULTISIG ...
+ /// </summary>
+ /// <param name="fAccurate">Legacy mode flag</param>
+ /// <returns>Amount of sigops</returns>
+ public uint GetSigOpCount(bool fAccurate)
+ {
+ var wCodeBytes = new InstructionQueue(ref codeBytes);
+
+ instruction opcode; // Current instruction
+ byte[] pushArgs; // OP_PUSHDATAn argument
+
+ uint nCount = 0;
+ var lastOpcode = instruction.OP_INVALIDOPCODE;
+
+ // Scan instructions sequence
+ while (ScriptCode.GetOp(ref wCodeBytes, out opcode, out pushArgs))
+ {
+ if (opcode == instruction.OP_CHECKSIG || opcode == instruction.OP_CHECKSIGVERIFY)
+ {
+ nCount++;
+ }
+ else if (opcode == instruction.OP_CHECKMULTISIG || opcode == instruction.OP_CHECKMULTISIGVERIFY)
+ {
+ if (fAccurate && lastOpcode >= instruction.OP_1 && lastOpcode <= instruction.OP_16)
+ {
+ nCount += (uint)ScriptCode.DecodeOP_N(lastOpcode);
+ }
+ else
+ {
+ nCount += 20;
+ }
+ }
+ }
+
+ return nCount;
+ }
+
+ /// <summary>
+ /// Accurately count sigOps, including sigOps in
+ /// pay-to-script-hash transactions
+ /// </summary>
+ /// <param name="scriptSig">pay-to-script-hash scriptPubKey</param>
+ /// <returns>SigOps count</returns>
+ public uint GetSigOpCount(CScript scriptSig)
+ {
+ if (!IsPayToScriptHash)
+ {
+ return GetSigOpCount(true);
+ }
+
+ // This is a pay-to-script-hash scriptPubKey;
+ // get the last item that the scriptSig
+ // pushes onto the stack:
+ InstructionQueue wScriptSig = scriptSig.GetInstructionQueue();
+ int nScriptSigSize = scriptSig.Size;
+
+ instruction opcode; // Current instruction
+ byte[] pushArgs = new byte[0]; // OP_PUSHDATAn argument
+
+
+ while (wScriptSig.Index < nScriptSigSize)
+ {
+ if (!ScriptCode.GetOp(ref wScriptSig, out opcode, out pushArgs))
+ {
+ return 0;
+ }
+
+ if (opcode > instruction.OP_16)
+ {
+ return 0;
+ }
+ }
+
+ /// ... and return its opcount:
+ var subScript = new CScript(pushArgs);
+
+ return subScript.GetSigOpCount(true);
+
+ }
+
+ /// <summary>
+ /// Set pay-to-pubkey destination.
+ /// </summary>
+ /// <param name="pubKey">Instance of CPubKey.</param>
+ public void SetDestination(CPubKey pubKey)
+ {
+ codeBytes.Clear();
+ PushData(pubKey);
+ AddInstruction(instruction.OP_CHECKSIG);
+ }
+
+ /// <summary>
+ /// Set pay-to-pubkeyhash destination
+ /// </summary>
+ /// <param name="ID">Public key hash</param>
+ public void SetDestination(CKeyID ID)
+ {
+ codeBytes.Clear();
+ AddInstruction(instruction.OP_DUP);
+ AddInstruction(instruction.OP_HASH160);
+ AddHash(ID);
+ AddInstruction(instruction.OP_EQUALVERIFY);
+ AddInstruction(instruction.OP_CHECKSIG);
+ }
+
+ /// <summary>
+ /// Set pay-to-scripthash destination
+ /// </summary>
+ /// <param name="ID">Script hash</param>
+ public void SetDestination(CScriptID ID)
+ {
+ codeBytes.Clear();
+ AddInstruction(instruction.OP_HASH160);
+ AddHash(ID);
+ AddInstruction(instruction.OP_EQUAL);
+ }
+
+ /// <summary>
+ /// Reset script code buffer.
+ /// </summary>
+ public void SetNullDestination()
+ {
+ codeBytes.Clear();
+ }
+
+ /// <summary>
+ /// Set multisig destination.
+ /// </summary>
+ /// <param name="nRequired">Amount of required signatures.</param>
+ /// <param name="keys">Set of public keys.</param>
+ public void SetMultiSig(int nRequired, CPubKey[] keys)
+ {
+ codeBytes.Clear();
+ AddInstruction(ScriptCode.EncodeOP_N(nRequired));
+
+ foreach (var key in keys)
+ {
+ PushData(key);
+ }
+
+ AddInstruction(ScriptCode.EncodeOP_N(keys.Length));
+ AddInstruction(instruction.OP_CHECKMULTISIG);
+ }
+
+ /// <summary>
+ /// Access to script code.
+ /// </summary>
+ public static implicit operator byte[] (CScript script)
+ {
+ return script.codeBytes.ToArray();
+ }
+
+ /// <summary>
+ /// Script size
+ /// </summary>
+ public int Size
+ {
+ get { return codeBytes.Count; }
+ }
+
+ public CScriptID ScriptID
+ {
+ get { return new CScriptID(Hash160.Compute160(codeBytes.ToArray())); }
+ }
+
+ /// <summary>
+ /// Disassemble current script code
+ /// </summary>
+ /// <returns>Code listing</returns>
public override string ToString()
{
- // TODO: disassembly
+ var sb = new StringBuilder();
+ var wCodeBytes = new InstructionQueue(ref codeBytes);
- StringBuilder sb = new StringBuilder();
+ instruction opcode; // Current instruction
+ byte[] pushArgs; // OP_PUSHDATAn argument
+ while (ScriptCode.GetOp(ref wCodeBytes, out opcode, out pushArgs))
+ {
+ if (sb.Length != 0)
+ {
+ sb.Append(" ");
+ }
+
+ if (0 <= opcode && opcode <= instruction.OP_PUSHDATA4)
+ {
+ sb.Append(ScriptCode.ValueString(pushArgs));
+ }
+ else
+ {
+ sb.Append(ScriptCode.GetOpName(opcode));
+ }
+ }
- //
-
return sb.ToString();
}
}
}
-