Merge branch 'segwit' of git://github.com/braydonf/btcjs into braydon…

…f-segwit

lib/address.js

@@ -259,11 +259,16 @@ Address._transformScript = function(script, network) {
  * @param {Array} publicKeys - a set of public keys to create an address
  * @param {number} threshold - the number of signatures needed to release the funds
  * @param {String|Network} network - either a Network instance, 'livenet', or 'testnet'
+ * @param {boolean=} nestedWitness - if the address uses a nested p2sh witness
  * @return {Address}
  */
-Address.createMultisig = function(publicKeys, threshold, network) {
+Address.createMultisig = function(publicKeys, threshold, network, nestedWitness) {
   network = network || publicKeys[0].network || Networks.defaultNetwork;
-  return Address.payingTo(Script.buildMultisigOut(publicKeys, threshold), network);
+  var redeemScript = Script.buildMultisigOut(publicKeys, threshold);
+  if (nestedWitness) {
+    return Address.payingTo(Script.buildWitnessMultisigOutFromScript(redeemScript), network);
+  }
+  return Address.payingTo(redeemScript, network);
 };
 
 /**
@@ -336,7 +341,6 @@ Address.fromScriptHash = function(hash, network) {
 Address.payingTo = function(script, network) {
   $.checkArgument(script, 'script is required');
   $.checkArgument(script instanceof Script, 'script must be instance of Script');
-
   return Address.fromScriptHash(Hash.sha256ripemd160(script.toBuffer()), network);
 };
 

lib/script/interpreter.js

@@ -31,6 +31,80 @@ var Interpreter = function Interpreter(obj) {
   }
 };
 
+Interpreter.prototype.verifyWitnessProgram = function(version, program, witness, satoshis, flags) {
+  var scriptPubKey = new Script();
+  var stack = [];
+
+  if (version === 0) {
+    if (program.length === 32) {
+      if (witness.length === 0) {
+        this.errstr = 'SCRIPT_ERR_WITNESS_PROGRAM_WITNESS_EMPTY';
+        return false;
+      }
+
+      var scriptPubKeyBuffer = witness[witness.length - 1];
+      scriptPubKey = new Script(scriptPubKeyBuffer);
+      var hash = Hash.sha256(scriptPubKeyBuffer);
+      if (hash.toString('hex') !== program.toString('hex')) {
+        this.errstr = 'SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH';
+        return false;
+      }
+
+      stack = witness.slice(0, -1);
+    } else if (program.length === 20) {
+      if (witness.length !== 2) {
+        this.errstr = 'SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH';
+        return false;
+      }
+
+      scriptPubKey.add(Opcode.OP_DUP);
+      scriptPubKey.add(Opcode.OP_HASH160);
+      scriptPubKey.add(program);
+      scriptPubKey.add(Opcode.OP_EQUALVERIFY);
+      scriptPubKey.add(Opcode.OP_CHECKSIG);
+
+      stack = witness;
+
+    } else {
+      this.errstr = 'SCRIPT_ERR_WITNESS_PROGRAM_WRONG_LENGTH';
+      return false;
+    }
+  } else if ((flags & Interpreter.SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM)) {
+    this.errstr = 'SCRIPT_ERR_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM';
+    return false;
+  } else {
+    return true;
+  }
+
+  this.initialize();
+
+  this.set({
+    script: scriptPubKey,
+    stack: stack,
+    sigversion: 1,
+    satoshis: satoshis
+  });
+
+  if (!this.evaluate()) {
+    return false;
+  }
+
+  if (this.stack.length !== 1) {
+    this.errstr = 'SCRIPT_ERR_EVAL_FALSE';
+    return false;
+  }
+
+  var buf = this.stack[this.stack.length - 1];
+  if (!Interpreter.castToBool(buf)) {
+    this.errstr = 'SCRIPT_ERR_EVAL_FALSE_IN_STACK';
+    return false;
+  }
+
+  return true;
+};
+
+
+
 /**
  * Verifies a Script by executing it and returns true if it is valid.
  * This function needs to be provided with the scriptSig and the scriptPubkey
@@ -41,10 +115,13 @@ var Interpreter = function Interpreter(obj) {
  *    to check signature validity for some opcodes like OP_CHECKSIG)
  * @param {number} nin - index of the transaction input containing the scriptSig verified.
  * @param {number} flags - evaluation flags. See Interpreter.SCRIPT_* constants
+ * @param {number} witness - array of witness data
+ * @param {number} satoshis - number of satoshis created by this output
  *
  * Translated from bitcoind's VerifyScript
  */
-Interpreter.prototype.verify = function(scriptSig, scriptPubkey, tx, nin, flags) {
+Interpreter.prototype.verify = function(scriptSig, scriptPubkey, tx, nin, flags, witness, satoshis) {
+
   var Transaction = require('../transaction');
   if (_.isUndefined(tx)) {
     tx = new Transaction();
@@ -55,10 +132,19 @@ Interpreter.prototype.verify = function(scriptSig, scriptPubkey, tx, nin, flags)
   if (_.isUndefined(flags)) {
     flags = 0;
   }
+  if (_.isUndefined(witness)) {
+    witness = null;
+  }
+  if (_.isUndefined(satoshis)) {
+    satoshis = 0;
+  }
+
   this.set({
     script: scriptSig,
     tx: tx,
     nin: nin,
+    sigversion: 0,
+    satoshis: 0,
     flags: flags
   });
   var stackCopy;
@@ -103,6 +189,22 @@ Interpreter.prototype.verify = function(scriptSig, scriptPubkey, tx, nin, flags)
     return false;
   }
 
+  var hadWitness = false;
+
+  if ((flags & Interpreter.SCRIPT_VERIFY_WITNESS)) {
+    var witnessValues = {};
+    if (scriptPubkey.isWitnessProgram(witnessValues)) {
+      hadWitness = true;
+      if (scriptSig.toBuffer().length !== 0) {
+        return false;
+      }
+
+      if (!this.verifyWitnessProgram(witnessValues.version, witnessValues.program, witness, satoshis, flags)) {
+        return false;
+      }
+    }
+  }
+
   // Additional validation for spend-to-script-hash transactions:
   if ((flags & Interpreter.SCRIPT_VERIFY_P2SH) && scriptPubkey.isScriptHashOut()) {
     // scriptSig must be literals-only or validation fails
@@ -144,8 +246,31 @@ Interpreter.prototype.verify = function(scriptSig, scriptPubkey, tx, nin, flags)
     if (!Interpreter.castToBool(stackCopy[stackCopy.length - 1])) {
       this.errstr = 'SCRIPT_ERR_EVAL_FALSE_IN_P2SH_STACK';
       return false;
-    } else {
-      return true;
+    }
+    if ((flags & Interpreter.SCRIPT_VERIFY_WITNESS)) {
+      var p2shWitnessValues = {};
+      if (redeemScript.isWitnessProgram(p2shWitnessValues)) {
+        hadWitness = true;
+        var redeemScriptPush = new Script();
+        redeemScriptPush.add(redeemScript.toBuffer());
+        if (scriptSig.toHex() !== redeemScriptPush.toHex()) {
+          this.errstr = 'SCRIPT_ERR_WITNESS_MALLEATED_P2SH';
+          return false;
+        }
+
+        if (!this.verifyWitnessProgram(p2shWitnessValues.version, p2shWitnessValues.program, witness, satoshis, flags)) {
+          return false;
+        }
+
+        stack = [stack[0]];
+      }
+    }
+
+    if ((flags & Interpreter.SCRIPT_VERIFY_WITNESS)) {
+      if (!hadWitness && witness.length > 0) {
+        this.errstr = 'SCRIPT_ERR_WITNESS_UNEXPECTED';
+        return false;
+      }
     }
   }
 
@@ -158,6 +283,8 @@ Interpreter.prototype.initialize = function(obj) {
   this.stack = [];
   this.altstack = [];
   this.pc = 0;
+  this.satoshis = 0;
+  this.sigversion = 0;
   this.pbegincodehash = 0;
   this.nOpCount = 0;
   this.vfExec = [];
@@ -173,6 +300,8 @@ Interpreter.prototype.set = function(obj) {
   this.altstack = obj.altack || this.altstack;
   this.pc = typeof obj.pc !== 'undefined' ? obj.pc : this.pc;
   this.pbegincodehash = typeof obj.pbegincodehash !== 'undefined' ? obj.pbegincodehash : this.pbegincodehash;
+  this.sigversion = typeof obj.sigversion !== 'undefined' ? obj.sigversion : this.sigversion;
+  this.satoshis = typeof obj.satoshis !== 'undefined' ? obj.satoshis : this.satoshis;
   this.nOpCount = typeof obj.nOpCount !== 'undefined' ? obj.nOpCount : this.nOpCount;
   this.vfExec = obj.vfExec || this.vfExec;
   this.errstr = obj.errstr || this.errstr;
@@ -191,6 +320,9 @@ Interpreter.LOCKTIME_THRESHOLD_BN = new BN(Interpreter.LOCKTIME_THRESHOLD);
 // bitcoind commit: b5d1b1092998bc95313856d535c632ea5a8f9104
 Interpreter.SCRIPT_VERIFY_NONE = 0;
 
+// Making v1-v16 witness program non-standard
+Interpreter.SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM = (1 << 12);
+
 // Evaluate P2SH subscripts (softfork safe, BIP16).
 Interpreter.SCRIPT_VERIFY_P2SH = (1 << 0);
 
@@ -231,6 +363,8 @@ Interpreter.SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS = (1 << 7);
 
 // CLTV See BIP65 for details.
 Interpreter.SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY = (1 << 9);
+Interpreter.SCRIPT_VERIFY_WITNESS = (1 << 10);
+Interpreter.SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS = (1 << 11);
 
 Interpreter.castToBool = function(buf) {
   for (var i = 0; i < buf.length; i++) {
@@ -1111,7 +1245,7 @@ Interpreter.prototype.step = function() {
           try {
             sig = Signature.fromTxFormat(bufSig);
             pubkey = PublicKey.fromBuffer(bufPubkey, false);
-            fSuccess = this.tx.verifySignature(sig, pubkey, this.nin, subscript);
+            fSuccess = this.tx.verifySignature(sig, pubkey, this.nin, subscript, this.sigversion, this.satoshis);
           } catch (e) {
             //invalid sig or pubkey
             fSuccess = false;
@@ -1200,7 +1334,7 @@ Interpreter.prototype.step = function() {
             try {
               sig = Signature.fromTxFormat(bufSig);
               pubkey = PublicKey.fromBuffer(bufPubkey, false);
-              fOk = this.tx.verifySignature(sig, pubkey, this.nin, subscript);
+              fOk = this.tx.verifySignature(sig, pubkey, this.nin, subscript, this.sigversion, this.satoshis);
             } catch (e) {
               //invalid sig or pubkey
               fOk = false;

lib/script/script.js

@@ -404,6 +404,49 @@ Script.prototype.isScriptHashOut = function() {
     buf[buf.length - 1] === Opcode.OP_EQUAL);
 };
 
+/**
+ * @returns {boolean} if this is a p2wsh output script
+ */
+Script.prototype.isWitnessScriptHashOut = function() {
+  var buf = this.toBuffer();
+  return (buf.length === 34 && buf[0] === 0 && buf[1] === 32);
+};
+
+/**
+ * @returns {boolean} if this is a p2wpkh output script
+ */
+Script.prototype.isWitnessPublicKeyHashOut = function() {
+  var buf = this.toBuffer();
+  return (buf.length === 22 && buf[0] === 0 && buf[1] === 20);
+};
+
+/**
+ * @param {Object=} values - The return values
+ * @param {Number} values.version - Set with the witness version
+ * @param {Buffer} values.program - Set with the witness program
+ * @returns {boolean} if this is a p2wpkh output script
+ */
+Script.prototype.isWitnessProgram = function(values) {
+  if (!values) {
+    values = {};
+  }
+  var buf = this.toBuffer();
+  if (buf.length < 4 || buf.length > 42) {
+    return false;
+  }
+  if (buf[0] !== Opcode.OP_0 && !(buf[0] >= Opcode.OP_1 && buf[0] <= Opcode.OP_16)) {
+    return false;
+  }
+
+  if (buf.length === buf[1] + 2) {
+    values.version = buf[0];
+    values.program = buf.slice(2, buf.length);
+    return true;
+  }
+
+  return false;
+};
+
 /**
  * @returns {boolean} if this is a p2sh input script
  * Note that these are frequently indistinguishable from pubkeyhashin
@@ -689,6 +732,15 @@ 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++) {
@@ -733,6 +785,17 @@ Script.buildMultisigOut = function(publicKeys, threshold, opts) {
   return script;
 };
 
+Script.buildWitnessMultisigOutFromScript = function(script) {
+  if (script instanceof Script) {
+    var s = new Script();
+    s.add(Opcode.OP_0);
+    s.add(Hash.sha256(script.toBuffer()));
+    return s;
+  } else {
+    throw new TypeError('First argument is expected to be a p2sh script');
+  }
+};
+
 /**
  * A new Multisig input script for the given public keys, requiring m of those public keys to spend
  *

lib/transaction/index.js

@@ -5,3 +5,4 @@ module.exports.Output = require('./output');
 module.exports.UnspentOutput = require('./unspentoutput');
 module.exports.Signature = require('./signature');
 module.exports.Sighash = require('./sighash');
+module.exports.SighashWitness = require('./sighashwitness');

lib/transaction/input/input.js

@@ -58,6 +58,7 @@ Input.prototype._fromObject = function(params) {
   } else {
     prevTxId = params.prevTxId;
   }
+  this.witnesses = [];
   this.output = params.output ?
     (params.output instanceof Output ? params.output : new Output(params.output)) : undefined;
   this.prevTxId = prevTxId || params.txidbuf;
@@ -153,6 +154,13 @@ Input.prototype.getSignatures = function() {
   );
 };
 
+Input.prototype.getSatoshisBuffer = function() {
+  $.checkState(this.output instanceof Output);
+  $.checkState(this.output._satoshisBN);
+  return new BufferWriter().writeUInt64LEBN(this.output._satoshisBN).toBuffer();
+};
+
+
 Input.prototype.isFullySigned = function() {
   throw new errors.AbstractMethodInvoked('Input#isFullySigned');
 };
@@ -169,6 +177,21 @@ Input.prototype.clearSignatures = function() {
   throw new errors.AbstractMethodInvoked('Input#clearSignatures');
 };
 
+Input.prototype.hasWitnesses = function() {
+  if (this.witnesses && this.witnesses.length > 0) {
+    return true;
+  }
+  return false;
+};
+
+Input.prototype.getWitnesses = function() {
+  return this.witnesses;
+};
+
+Input.prototype.setWitnesses = function(witnesses) {
+  this.witnesses = witnesses;
+};
+
 Input.prototype.isValidSignature = function(transaction, signature) {
   // FIXME: Refactor signature so this is not necessary
   signature.signature.nhashtype = signature.sigtype;