X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=Novacoin%2FCScript.cs;h=95ca17a88e5dc7898e8d896170bf94cb10b74908;hb=0fe762d6eee8a8a23033f813217c1675a34f2d6a;hp=7728d4cd7b4fb38d53207eb538270eed3c83fdad;hpb=961746f76873ef56ce65607ef981f2a2afaeb21d;p=NovacoinLibrary.git

diff --git a/Novacoin/CScript.cs b/Novacoin/CScript.cs
index 7728d4c..95ca17a 100644
--- a/Novacoin/CScript.cs
+++ b/Novacoin/CScript.cs
@@ -1,31 +1,547 @@
-using System;
-using System.Text;
+/**
+ *  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">uint160 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">uint256 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();
 		}
 	}
 }
-