rpc: fix wit commitment for getblocktemplate.

lib/http/rpc.js

@@ -1307,6 +1307,8 @@ RPC.prototype._createTemplate = co(function* _createTemplate(version, coinbase,
     output = tx.outputs[tx.outputs.length - 1];
     assert(output.script.isCommitment());
     json.default_witness_commitment = output.script.toJSON();
+  } else if (rules && rules.indexOf('segwit') !== -1) {
+    json.default_witness_commitment = attempt.getWitnessScript().toJSON();
   }
 
   return json;

lib/mining/template.js

@@ -52,6 +52,7 @@ function BlockTemplate(options) {
   this.interval = 210000;
   this.fees = 0;
   this.tree = new MerkleTree();
+  this.commitment = DUMMY;
   this.left = DUMMY;
   this.right = DUMMY;
   this.items = [];
@@ -188,6 +189,15 @@ BlockTemplate.prototype.getWitnessHash = function getWitnessHash() {
   return crypto.hash256(data);
 };
 
+/**
+ * Create witness commitment script.
+ * @returns {Script}
+ */
+
+BlockTemplate.prototype.getWitnessScript = function getWitnessScript() {
+  return Script.fromCommitment(this.commitment);
+};
+
 /**
  * Set the target (bits).
  * @param {Number} bits
@@ -222,14 +232,15 @@ BlockTemplate.prototype.getReward = function getReward() {
 
 /**
  * Initialize the default coinbase.
+ * @param {Buffer} hash - Witness commitment hash.
  * @returns {TX}
  */
 
-BlockTemplate.prototype.createCoinbase = function createCoinbase() {
+BlockTemplate.prototype.createCoinbase = function createCoinbase(hash) {
   var scale = consensus.WITNESS_SCALE_FACTOR;
   var cb = new TX();
   var padding = 0;
-  var input, output, commit, hash;
+  var input, output, commit;
 
   // Coinbase input.
   input = new Input();
@@ -241,11 +252,11 @@ BlockTemplate.prototype.createCoinbase = function createCoinbase() {
   input.script.push(encoding.ZERO_HASH160);
 
   // Smaller nonce for good measure.
-  input.script.push(util.nonce().slice(0, 4));
+  input.script.push(util.nonce(4));
 
   // Extra nonce: incremented when
   // the nonce overflows.
-  input.script.push(extraNonce(0, 0));
+  input.script.push(encoding.ZERO_U64);
 
   input.script.compile();
 
@@ -269,7 +280,6 @@ BlockTemplate.prototype.createCoinbase = function createCoinbase() {
   if (this.witness) {
     // Commitment output.
     commit = new Output();
-    hash = this.getWitnessHash();
     commit.script.fromCommitment(hash);
     cb.outputs.push(commit);
   }
@@ -320,7 +330,8 @@ BlockTemplate.prototype.createCoinbase = function createCoinbase() {
  */
 
 BlockTemplate.prototype.refresh = function refresh() {
-  var cb = this.createCoinbase();
+  var hash = this.getWitnessHash();
+  var cb = this.createCoinbase(hash);
   var raw = cb.toNormal();
   var size = 0;
   var left, right;
@@ -338,6 +349,7 @@ BlockTemplate.prototype.refresh = function refresh() {
   size += 4 + 4; // nonce1 + nonce2
   right = raw.slice(size);
 
+  this.commitment = hash;
   this.left = left;
   this.right = right;
   this.tree = MerkleTree.fromItems(this.items);
@@ -644,6 +656,38 @@ BlockEntry.fromEntry = function fromEntry(entry, attempt) {
   return item;
 };
 
+/*
+ * BlockProof
+ * @constructor
+ * @param {Hash} hash
+ * @param {Hash} root
+ * @param {Number} nonce1
+ * @param {Number} nonce2
+ * @param {Number} ts
+ * @param {Number} nonce
+ */
+
+function BlockProof(hash, root, nonce1, nonce2, ts, nonce) {
+  this.hash = hash;
+  this.root = root;
+  this.nonce1 = nonce1;
+  this.nonce2 = nonce2;
+  this.ts = ts;
+  this.nonce = nonce;
+}
+
+BlockProof.prototype.rhash = function rhash() {
+  return util.revHex(this.hash.toString('hex'));
+};
+
+BlockProof.prototype.verify = function verify(target) {
+  return common.rcmp(this.hash, target) <= 0;
+};
+
+BlockProof.prototype.getDifficulty = function getDifficulty() {
+  return common.getDifficulty(this.hash);
+};
+
 /*
  * MerkleTree
  * @constructor
@@ -743,49 +787,6 @@ MerkleTree.fromLeaves = function fromLeaves(leaves) {
   return new MerkleTree().fromLeaves(leaves);
 };
 
-/*
- * BlockProof
- * @constructor
- * @param {Hash} hash
- * @param {Hash} root
- * @param {Number} nonce1
- * @param {Number} nonce2
- * @param {Number} ts
- * @param {Number} nonce
- */
-
-function BlockProof(hash, root, nonce1, nonce2, ts, nonce) {
-  this.hash = hash;
-  this.root = root;
-  this.nonce1 = nonce1;
-  this.nonce2 = nonce2;
-  this.ts = ts;
-  this.nonce = nonce;
-}
-
-BlockProof.prototype.rhash = function rhash() {
-  return util.revHex(this.hash.toString('hex'));
-};
-
-BlockProof.prototype.verify = function verify(target) {
-  return common.rcmp(this.hash, target) <= 0;
-};
-
-BlockProof.prototype.getDifficulty = function getDifficulty() {
-  return common.getDifficulty(this.hash);
-};
-
-/*
- * Helpers
- */
-
-function extraNonce(nonce1, nonce2) {
-  var bw = new StaticWriter(8);
-  bw.writeU32BE(nonce1);
-  bw.writeU32BE(nonce2);
-  return bw.render();
-};
-
 /*
  * Expose
  */

lib/utils/util.js

@@ -568,17 +568,34 @@ util.random = function random(min, max) {
 };
 
 /**
- * Create a 64 bit nonce.
+ * Create a 32 or 64 bit nonce.
+ * @param {Number} size
  * @returns {Buffer}
  */
 
-util.nonce = function _nonce() {
+util.nonce = function _nonce(size) {
-  var nonce = new Buffer(8);
+  var n, nonce;
-  var a = util.random(0, 0x100000000);
-  var b = util.random(0, 0x100000000);
 
-  nonce.writeUInt32LE(a, 0, true);
+  if (!size)
-  nonce.writeUInt32LE(b, 4, true);
+    size = 8;
+
+  switch (size) {
+    case 8:
+      nonce = new Buffer(8);
+      n = util.random(0, 0x100000000);
+      nonce.writeUInt32LE(n, 0, true);
+      n = util.random(0, 0x100000000);
+      nonce.writeUInt32LE(n, 4, true);
+      break;
+    case 4:
+      nonce = new Buffer(4);
+      n = util.random(0, 0x100000000);
+      nonce.writeUInt32LE(n, 0, true);
+      break;
+    default:
+      assert(false, 'Bad nonce size.');
+      break;
+  }
 
   return nonce;
 };