transaction: start to use new sighash for nested witness

lib/script/script.js

@@ -689,6 +689,15 @@ Script.prototype._addBuffer = function(buf, prepend) {
   return this;
 };
 
+Script.prototype.hasCodeseparators = function() {
+  for (var i = 0; i < this.chunks.length; i++) {
+    if (this.chunks[i].opcodenum === Opcode.OP_CODESEPARATOR) {
+      return true;
+    }
+  }
+  return false;
+};
+
 Script.prototype.removeCodeseparators = function() {
   var chunks = [];
   for (var i = 0; i < this.chunks.length; i++) {

lib/transaction/input/multisigscripthash.js

@@ -11,6 +11,8 @@ var $ = require('../../util/preconditions');
 var Script = require('../../script');
 var Signature = require('../../crypto/signature');
 var Sighash = require('../sighash');
+var SighashWitness = require('../sighashwitness');
+var BufferWriter = require('../../encoding/bufferwriter');
 var BufferUtil = require('../../util/buffer');
 var TransactionSignature = require('../signature');
 
@@ -74,6 +76,24 @@ MultiSigScriptHashInput.prototype._serializeSignatures = function() {
   });
 };
 
+MultiSigScriptHashInput.prototype.getScriptCode = function() {
+  var writer = new BufferWriter();
+  if (!this.script.hasCodeseparators()) {
+    writer.writeVarintNum(this._scriptBuffer.length);
+    writer.write(this._scriptBuffer);
+  } else {
+    throw new Error('@TODO');
+  }
+  return writer.toBuffer();
+};
+
+MultiSigScriptHashInput.prototype.getSatoshisBuffer = function() {
+  $.checkState(this.output instanceof Output);
+  $.checkState(this.output._satoshisBN);
+  var buffer = new BufferWriter().writeUInt64LEBN(this.output._satoshisBN).toBuffer();
+  return buffer;
+};
+
 MultiSigScriptHashInput.prototype.getSignatures = function(transaction, privateKey, index, sigtype) {
   $.checkState(this.output instanceof Output);
   sigtype = sigtype || Signature.SIGHASH_ALL;
@@ -82,12 +102,20 @@ MultiSigScriptHashInput.prototype.getSignatures = function(transaction, privateK
   var results = [];
   _.each(this.publicKeys, function(publicKey) {
     if (publicKey.toString() === privateKey.publicKey.toString()) {
+      var signature;
+      if (self.nestedWitness) {
+        var scriptCode = self.getScriptCode();
+        var satoshisBuffer = self.getSatoshisBuffer();
+        signature = SighashWitness.sign(transaction, privateKey, sigtype, index, scriptCode, satoshisBuffer);
+      } else  {
+        signature = Sighash.sign(transaction, privateKey, sigtype, index, self.redeemScript);
+      }
       results.push(new TransactionSignature({
         publicKey: privateKey.publicKey,
         prevTxId: self.prevTxId,
         outputIndex: self.outputIndex,
         inputIndex: index,
-        signature: Sighash.sign(transaction, privateKey, sigtype, index, self.redeemScript),
+        signature: signature,
         sigtype: sigtype
       }));
     }
@@ -159,15 +187,29 @@ MultiSigScriptHashInput.prototype.publicKeysWithoutSignature = function() {
 };
 
 MultiSigScriptHashInput.prototype.isValidSignature = function(transaction, signature) {
-  // FIXME: Refactor signature so this is not necessary
-  signature.signature.nhashtype = signature.sigtype;
-  return Sighash.verify(
+  if (this.nestedWitness) {
+    signature.signature.nhashtype = signature.sigtype;
+    var scriptCode = this.getScriptCode();
+    var satoshisBuffer = this.getSatoshisBuffer();
+    return SighashWitness.verify(
+      transaction,
+      signature.signature,
+      signature.publicKey,
+      signature.inputIndex,
+      scriptCode,
+      satoshisBuffer
+    );
+  } else {
+    // FIXME: Refactor signature so this is not necessary
+    signature.signature.nhashtype = signature.sigtype;
+    return Sighash.verify(
       transaction,
       signature.signature,
       signature.publicKey,
       signature.inputIndex,
       this.redeemScript
-  );
+    );
+  }
 };
 
 MultiSigScriptHashInput.OPCODES_SIZE = 7; // serialized size (<=3) + 0 .. N .. M OP_CHECKMULTISIG

lib/transaction/sighashwitness.js

@@ -111,8 +111,8 @@ var sighash = function sighash(transaction, sighashType, inputNumber, scriptCode
  * @param {Script} subscript
  * @return {Signature}
  */
-function sign(transaction, privateKey, sighashType, inputIndex, subscript) {
-  var hashbuf = sighash(transaction, sighashType, inputIndex, subscript);
+function sign(transaction, privateKey, sighashType, inputIndex, scriptCode, satoshisBuffer) {
+  var hashbuf = sighash(transaction, sighashType, inputIndex, scriptCode, satoshisBuffer);
   var sig = ECDSA.sign(hashbuf, privateKey, 'little').set({
     nhashtype: sighashType
   });
@@ -130,10 +130,10 @@ function sign(transaction, privateKey, sighashType, inputIndex, subscript) {
  * @param {Script} subscript
  * @return {boolean}
  */
-function verify(transaction, signature, publicKey, inputIndex, subscript) {
+function verify(transaction, signature, publicKey, inputIndex, scriptCode, satoshisBuffer) {
   $.checkArgument(!_.isUndefined(transaction));
   $.checkArgument(!_.isUndefined(signature) && !_.isUndefined(signature.nhashtype));
-  var hashbuf = sighash(transaction, signature.nhashtype, inputIndex, subscript);
+  var hashbuf = sighash(transaction, signature.nhashtype, inputIndex, scriptCode, satoshisBuffer);
   return ECDSA.verify(hashbuf, signature, publicKey, 'little');
 }
 

test/transaction/input/multisigscripthash.js

@@ -111,4 +111,37 @@ describe('MultiSigScriptHashInput', function() {
     var roundtrip = new MultiSigScriptHashInput(input.toObject());
     roundtrip.toObject().should.deep.equal(input.toObject());
   });
+  it('will get the scriptCode for nested witness', function() {
+    var address = Address.createMultisig([public1, public2, public3], 2, 'testnet', true);
+    var utxo = {
+      address: address.toString(),
+      txId: '66e64ef8a3b384164b78453fa8c8194de9a473ba14f89485a0e433699daec140',
+      outputIndex: 0,
+      script: new Script(address),
+      satoshis: 1000000
+    };
+    var transaction = new Transaction()
+      .from(utxo, [public1, public2, public3], 2, true)
+      .to(address, 1000000);
+    var input = transaction.inputs[0];
+    var scriptCode = input.getScriptCode();
+    scriptCode.toString('hex').should.equal('2200206aac01b83b1537afe2aa96d13a339b8a109b05f6eaf37d5840fe5f227daedacc');
+  });
+  it('will get the satoshis buffer for nested witness', function() {
+    var address = Address.createMultisig([public1, public2, public3], 2, 'testnet', true);
+    var utxo = {
+      address: address.toString(),
+      txId: '66e64ef8a3b384164b78453fa8c8194de9a473ba14f89485a0e433699daec140',
+      outputIndex: 0,
+      script: new Script(address),
+      satoshis: 1000000
+    };
+    var transaction = new Transaction()
+      .from(utxo, [public1, public2, public3], 2, true)
+      .to(address, 1000000);
+    var input = transaction.inputs[0];
+    var satoshisBuffer = input.getSatoshisBuffer();
+    satoshisBuffer.toString('hex').should.equal('40420f0000000000');
+  });
+
 });

test/transaction/transaction.js

@@ -1266,7 +1266,7 @@ describe('Transaction', function() {
         address: address.toString(),
         txId: '72a0b3d6dcbba9d2ae74c11eec05cdfc2a03e1a01b3bbb09af0cc2dc8c3dbefa',
         outputIndex: 0,
-        script: Script.buildScriptHashOut(address).toString(),
+        script: Script.buildScriptHashOut(address).toHex(),
         satoshis: 1e8
       };
       it('will sign with nested p2sh witness program', function() {
@@ -1277,6 +1277,7 @@ describe('Transaction', function() {
           .change('DF8MrzMiDkTvT4qpeCAdW6Y37WGgbo9Cmu')
           .sign(privateKey1)
           .sign(privateKey2);
+        // TODO: check correct signature
       });
     });
   });