Misc. improvements and cleanups

src/payments/p2tr.js

@@ -12,7 +12,6 @@ const verifyecc_1 = require('./verifyecc');
 const OPS = bscript.OPS;
 const TAPROOT_WITNESS_VERSION = 0x01;
 const ANNEX_PREFIX = 0x50;
-const LEAF_VERSION_MASK = 0b11111110;
 function p2tr(a, opts) {
  if (
  !a.address &&
@@ -41,7 +40,7 @@ function p2tr(a, opts) {
  witness: types_1.typeforce.maybe(
  types_1.typeforce.arrayOf(types_1.typeforce.Buffer),
  ),
- scriptTree: types_1.typeforce.maybe(taprootutils_1.isTapTree),
+ scriptTree: types_1.typeforce.maybe(types_1.isTaptree),
  redeem: types_1.typeforce.maybe({
  output: types_1.typeforce.maybe(types_1.typeforce.Buffer),
  redeemVersion: types_1.typeforce.maybe(types_1.typeforce.Number),
@@ -74,6 +73,11 @@ function p2tr(a, opts) {
  }
  return a.witness.slice();
  });
+ const _hashTree = lazy.value(() => {
+ if (a.scriptTree) return (0, taprootutils_1.toHashTree)(a.scriptTree);
+ if (a.hash) return { hash: a.hash };
+ return;
+ });
  const network = a.network || networks_1.bitcoin;
  const o = { name: 'p2tr', network };
  lazy.prop(o, 'address', () => {
@@ -83,14 +87,17 @@ function p2tr(a, opts) {
  return bech32_1.bech32m.encode(network.bech32, words);
  });
  lazy.prop(o, 'hash', () => {
- if (a.hash) return a.hash;
- if (a.scriptTree) return (0, taprootutils_1.toHashTree)(a.scriptTree).hash;
+ const hashTree = _hashTree();
+ if (hashTree) return hashTree.hash;
  const w = _witness();
  if (w && w.length > 1) {
  const controlBlock = w[w.length - 1];
- const leafVersion = controlBlock[0] & LEAF_VERSION_MASK;
+ const leafVersion = controlBlock[0] & types_1.TAPLEAF_VERSION_MASK;
  const script = w[w.length - 2];
- const leafHash = (0, taprootutils_1.tapLeafHash)(script, leafVersion);
+ const leafHash = (0, taprootutils_1.tapleafHash)({
+ output: script,
+ version: leafVersion,
+ });
  return (0, taprootutils_1.rootHashFromPath)(controlBlock, leafHash);
  }
  return null;
@@ -116,7 +123,8 @@ function p2tr(a, opts) {
  return {
  output: witness[witness.length - 2],
  witness: witness.slice(0, -2),
- redeemVersion: witness[witness.length - 1][0] & LEAF_VERSION_MASK,
+ redeemVersion:
+ witness[witness.length - 1][0] & types_1.TAPLEAF_VERSION_MASK,
  };
  });
  lazy.prop(o, 'pubkey', () => {
@@ -141,14 +149,14 @@ function p2tr(a, opts) {
  });
  lazy.prop(o, 'witness', () => {
  if (a.witness) return a.witness;
- if (a.scriptTree && a.redeem && a.redeem.output && a.internalPubkey) {
- // todo: optimize/cache
- const hashTree = (0, taprootutils_1.toHashTree)(a.scriptTree);
- const leafHash = (0, taprootutils_1.tapLeafHash)(
- a.redeem.output,
- o.redeemVersion,
- );
+ const hashTree = _hashTree();
+ if (hashTree && a.redeem && a.redeem.output && a.internalPubkey) {
+ const leafHash = (0, taprootutils_1.tapleafHash)({
+ output: a.redeem.output,
+ version: o.redeemVersion,
+ });
  const path = (0, taprootutils_1.findScriptPath)(hashTree, leafHash);
+ if (!path) return;
  const outputKey = tweakKey(a.internalPubkey, hashTree.hash, _ecc());
  if (!outputKey) return;
  const controlBock = buffer_1.Buffer.concat(
@@ -200,7 +208,7 @@ function p2tr(a, opts) {
  throw new TypeError('Invalid pubkey for p2tr');
  }
  if (a.hash && a.scriptTree) {
- const hash = (0, taprootutils_1.toHashTree)(a.scriptTree).hash;
+ const hash = _hashTree().hash;
  if (!a.hash.equals(hash)) throw new TypeError('Hash mismatch');
  }
  const witness = _witness();
@@ -253,9 +261,12 @@ function p2tr(a, opts) {
  throw new TypeError('Internal pubkey mismatch');
  if (!_ecc().isXOnlyPoint(internalPubkey))
  throw new TypeError('Invalid internalPubkey for p2tr witness');
- const leafVersion = controlBlock[0] & LEAF_VERSION_MASK;
+ const leafVersion = controlBlock[0] & types_1.TAPLEAF_VERSION_MASK;
  const script = witness[witness.length - 2];
- const leafHash = (0, taprootutils_1.tapLeafHash)(script, leafVersion);
+ const leafHash = (0, taprootutils_1.tapleafHash)({
+ output: script,
+ version: leafVersion,
+ });
  const hash = (0, taprootutils_1.rootHashFromPath)(
  controlBlock,
  leafHash,

src/payments/taprootutils.d.ts

@@ -1,12 +1,16 @@
 /// <reference types="node" />
-import { Taptree } from '../types';
+import { Tapleaf, Taptree } from '../types';
 export declare const LEAF_VERSION_TAPSCRIPT = 192;
-export declare function rootHashFromPath(controlBlock: Buffer, tapLeafMsg: Buffer): Buffer;
-export interface HashTree {
+export declare function rootHashFromPath(controlBlock: Buffer, leafHash: Buffer): Buffer;
+interface HashLeaf {
  hash: Buffer;
- left?: HashTree;
- right?: HashTree;
 }
+interface HashBranch {
+ hash: Buffer;
+ left: HashTree;
+ right: HashTree;
+}
+export declare type HashTree = HashLeaf | HashBranch;
 /**
  * Build the hash tree from the scripts binary tree.
  * The binary tree can be balanced or not.
@@ -16,16 +20,13 @@ export interface HashTree {
  * - one taproot leaf and a list of elements
  */
 export declare function toHashTree(scriptTree: Taptree): HashTree;
-/**
- * Check if the tree is a binary tree with leafs of type Tapleaf
- */
-export declare function isTapTree(scriptTree: Taptree): boolean;
 /**
  * Given a MAST tree, it finds the path of a particular hash.
  * @param node - the root of the tree
  * @param hash - the hash to search for
- * @returns - and array of hashes representing the path, or an empty array if no pat is found
+ * @returns - and array of hashes representing the path, undefined if no path is found
  */
-export declare function findScriptPath(node: HashTree, hash: Buffer): Buffer[];
-export declare function tapLeafHash(script: Buffer, version?: number): Buffer;
+export declare function findScriptPath(node: HashTree, hash: Buffer): Buffer[] | undefined;
+export declare function tapleafHash(leaf: Tapleaf): Buffer;
 export declare function tapTweakHash(pubKey: Buffer, h: Buffer | undefined): Buffer;
+export {};

src/payments/taprootutils.js

@@ -1,28 +1,26 @@
 'use strict';
 Object.defineProperty(exports, '__esModule', { value: true });
-exports.tapTweakHash = exports.tapLeafHash = exports.findScriptPath = exports.isTapTree = exports.toHashTree = exports.rootHashFromPath = exports.LEAF_VERSION_TAPSCRIPT = void 0;
+exports.tapTweakHash = exports.tapleafHash = exports.findScriptPath = exports.toHashTree = exports.rootHashFromPath = exports.LEAF_VERSION_TAPSCRIPT = void 0;
 const buffer_1 = require('buffer');
 const bcrypto = require('../crypto');
 const bufferutils_1 = require('../bufferutils');
-const TAP_LEAF_TAG = 'TapLeaf';
-const TAP_BRANCH_TAG = 'TapBranch';
-const TAP_TWEAK_TAG = 'TapTweak';
+const types_1 = require('../types');
 exports.LEAF_VERSION_TAPSCRIPT = 0xc0;
-function rootHashFromPath(controlBlock, tapLeafMsg) {
- const k = [tapLeafMsg];
- const e = [];
+function rootHashFromPath(controlBlock, leafHash) {
  const m = (controlBlock.length - 33) / 32;
+ let kj = leafHash;
  for (let j = 0; j < m; j++) {
- e[j] = controlBlock.slice(33 + 32 * j, 65 + 32 * j);
- if (k[j].compare(e[j]) < 0) {
- k[j + 1] = tapBranchHash(k[j], e[j]);
+ const ej = controlBlock.slice(33 + 32 * j, 65 + 32 * j);
+ if (kj.compare(ej) < 0) {
+ kj = tapBranchHash(kj, ej);
  } else {
- k[j + 1] = tapBranchHash(e[j], k[j]);
+ kj = tapBranchHash(ej, kj);
  }
  }
- return k[m];
+ return kj;
 }
 exports.rootHashFromPath = rootHashFromPath;
+const isHashBranch = ht => 'left' in ht && 'right' in ht;
 /**
  * Build the hash tree from the scripts binary tree.
  * The binary tree can be balanced or not.
@@ -32,90 +30,59 @@ exports.rootHashFromPath = rootHashFromPath;
  * - one taproot leaf and a list of elements
  */
 function toHashTree(scriptTree) {
- if (scriptTree.length === 1) {
- const script = scriptTree[0];
- if (Array.isArray(script)) {
- return toHashTree(script);
- }
- script.version = script.version || exports.LEAF_VERSION_TAPSCRIPT;
- if ((script.version & 1) !== 0)
- throw new TypeError('Invalid script version');
- return {
- hash: tapLeafHash(script.output, script.version),
- };
- }
- let left = toHashTree([scriptTree[0]]);
- let right = toHashTree([scriptTree[1]]);
- if (left.hash.compare(right.hash) === 1) [left, right] = [right, left];
+ if ((0, types_1.isTapleaf)(scriptTree))
+ return { hash: tapleafHash(scriptTree) };
+ const hashes = [toHashTree(scriptTree[0]), toHashTree(scriptTree[1])];
+ hashes.sort((a, b) => a.hash.compare(b.hash));
+ const [left, right] = hashes;
  return {
  hash: tapBranchHash(left.hash, right.hash),
  left,
  right,
  };
 }
 exports.toHashTree = toHashTree;
-/**
- * Check if the tree is a binary tree with leafs of type Tapleaf
- */
-function isTapTree(scriptTree) {
- if (scriptTree.length > 2) return false;
- if (scriptTree.length === 1) {
- const script = scriptTree[0];
- if (Array.isArray(script)) {
- return isTapTree(script);
- }
- if (!script.output) return false;
- script.version = script.version || exports.LEAF_VERSION_TAPSCRIPT;
- if ((script.version & 1) !== 0) return false;
- return true;
- }
- if (!isTapTree([scriptTree[0]])) return false;
- if (!isTapTree([scriptTree[1]])) return false;
- return true;
-}
-exports.isTapTree = isTapTree;
 /**
  * Given a MAST tree, it finds the path of a particular hash.
  * @param node - the root of the tree
  * @param hash - the hash to search for
- * @returns - and array of hashes representing the path, or an empty array if no pat is found
+ * @returns - and array of hashes representing the path, undefined if no path is found
  */
 function findScriptPath(node, hash) {
- if (node.left) {
- if (node.left.hash.equals(hash)) return node.right ? [node.right.hash] : [];
- const leftPath = findScriptPath(node.left, hash);
- if (leftPath.length)
- return node.right ? [node.right.hash].concat(leftPath) : leftPath;
- }
- if (node.right) {
- if (node.right.hash.equals(hash)) return node.left ? [node.left.hash] : [];
- const rightPath = findScriptPath(node.right, hash);
- if (rightPath.length)
- return node.left ? [node.left.hash].concat(rightPath) : rightPath;
+ if (!isHashBranch(node)) {
+ if (node.hash.equals(hash)) {
+ return [];
+ } else {
+ return undefined;
+ }
  }
- return [];
+ const leftPath = findScriptPath(node.left, hash);
+ if (leftPath !== undefined) return [node.right.hash, ...leftPath];
+ const rightPath = findScriptPath(node.right, hash);
+ if (rightPath !== undefined) return [node.left.hash, ...rightPath];
+ return undefined;
 }
 exports.findScriptPath = findScriptPath;
-function tapLeafHash(script, version) {
- version = version || exports.LEAF_VERSION_TAPSCRIPT;
+function tapleafHash(leaf) {
+ const version = leaf.version || exports.LEAF_VERSION_TAPSCRIPT;
  return bcrypto.taggedHash(
- TAP_LEAF_TAG,
+ 'TapLeaf',
  buffer_1.Buffer.concat([
  buffer_1.Buffer.from([version]),
- serializeScript(script),
+ serializeScript(leaf.output),
  ]),
  );
 }
-exports.tapLeafHash = tapLeafHash;
+exports.tapleafHash = tapleafHash;
 function tapTweakHash(pubKey, h) {
  return bcrypto.taggedHash(
- TAP_TWEAK_TAG,
+ 'TapTweak',
  buffer_1.Buffer.concat(h ? [pubKey, h] : [pubKey]),
  );
 }
 exports.tapTweakHash = tapTweakHash;
 function tapBranchHash(a, b) {
- return bcrypto.taggedHash(TAP_BRANCH_TAG, buffer_1.Buffer.concat([a, b]));
+ return bcrypto.taggedHash('TapBranch', buffer_1.Buffer.concat([a, b]));
 }
 function serializeScript(s) {
  const varintLen = bufferutils_1.varuint.encodingLength(s.length);

src/psbt.js

@@ -1079,7 +1079,7 @@ function getHashForSig(
  const signingScripts = prevOuts.map(o => o.script);
  const values = prevOuts.map(o => o.value);
  const leafHash = input.witnessScript
- ? (0, taprootutils_1.tapLeafHash)(input.witnessScript)
+ ? (0, taprootutils_1.tapleafHash)({ output: input.witnessScript })
  : undefined;
  hash = unsignedTx.hashForWitnessV1(
  inputIndex,

src/types.d.ts

@@ -18,7 +18,10 @@ export interface Tapleaf {
  output: Buffer;
  version?: number;
 }
-export declare type Taptree = Array<[Tapleaf, Tapleaf] | Tapleaf>;
+export declare const TAPLEAF_VERSION_MASK = 254;
+export declare function isTapleaf(o: any): o is Tapleaf;
+export declare type Taptree = [Taptree | Tapleaf, Taptree | Tapleaf] | Tapleaf;
+export declare function isTaptree(scriptTree: any): scriptTree is Taptree;
 export interface TinySecp256k1Interface {
  isXOnlyPoint(p: Uint8Array): boolean;
  xOnlyPointAddTweak(p: Uint8Array, tweak: Uint8Array): XOnlyPointAddTweakResult | null;

src/types.js

@@ -1,6 +1,6 @@
 'use strict';
 Object.defineProperty(exports, '__esModule', { value: true });
-exports.oneOf = exports.Null = exports.BufferN = exports.Function = exports.UInt32 = exports.UInt8 = exports.tuple = exports.maybe = exports.Hex = exports.Buffer = exports.String = exports.Boolean = exports.Array = exports.Number = exports.Hash256bit = exports.Hash160bit = exports.Buffer256bit = exports.Network = exports.ECPoint = exports.Satoshi = exports.Signer = exports.BIP32Path = exports.UInt31 = exports.isPoint = exports.typeforce = void 0;
+exports.oneOf = exports.Null = exports.BufferN = exports.Function = exports.UInt32 = exports.UInt8 = exports.tuple = exports.maybe = exports.Hex = exports.Buffer = exports.String = exports.Boolean = exports.Array = exports.Number = exports.Hash256bit = exports.Hash160bit = exports.Buffer256bit = exports.isTaptree = exports.isTapleaf = exports.TAPLEAF_VERSION_MASK = exports.Network = exports.ECPoint = exports.Satoshi = exports.Signer = exports.BIP32Path = exports.UInt31 = exports.isPoint = exports.typeforce = void 0;
 const buffer_1 = require('buffer');
 exports.typeforce = require('typeforce');
 const ZERO32 = buffer_1.Buffer.alloc(32, 0);
@@ -68,6 +68,21 @@ exports.Network = exports.typeforce.compile({
  scriptHash: exports.typeforce.UInt8,
  wif: exports.typeforce.UInt8,
 });
+exports.TAPLEAF_VERSION_MASK = 0xfe;
+function isTapleaf(o) {
+ if (!('output' in o)) return false;
+ if (!buffer_1.Buffer.isBuffer(o.output)) return false;
+ if (o.version !== undefined)
+ return (o.version & exports.TAPLEAF_VERSION_MASK) === o.version;
+ return true;
+}
+exports.isTapleaf = isTapleaf;
+function isTaptree(scriptTree) {
+ if (!(0, exports.Array)(scriptTree)) return isTapleaf(scriptTree);
+ if (scriptTree.length !== 2) return false;
+ return scriptTree.every(t => isTaptree(t));
+}
+exports.isTaptree = isTaptree;
 exports.Buffer256bit = exports.typeforce.BufferN(32);
 exports.Hash160bit = exports.typeforce.BufferN(20);
 exports.Hash256bit = exports.typeforce.BufferN(32);