Merge pull request #145 from handshake-org/create-rpcs

wallet: support alternative signers

This PR introduces new RPC calls which create unsigned txs for each covenant type. It also adds a new WalletCoinView class that extends CoinView and stores HD paths. These paths allow alternative, HD wallets to create valid input signatures. The MTX class has also been updated to persist coin information during de/serialization. Finally, this commit adds support for unsigned auction transactions to the HTTP API.

Author: boymanjor

lib/coins/coinview.js

@@ -298,6 +298,17 @@ class CoinView extends View {
     return coins.getOutput(index);
   }
 
+  /**
+   * Get an HD path by prevout.
+   * Implemented in {@link WalletCoinView}.
+   * @param {Outpoint} prevout
+   * @returns {null}
+   */
+
+  getPath(prevout) {
+    return null;
+  }
+
   /**
    * Get coins height by prevout.
    * @param {Outpoint} prevout
@@ -378,6 +389,17 @@ class CoinView extends View {
     return this.getOutput(input.prevout);
   }
 
+  /**
+   * Get a single path by input.
+   * Implemented in {@link WalletCoinView}.
+   * @param {Input} input
+   * @returns {null}
+   */
+
+  getPathFor(input) {
+    return null;
+  }
+
   /**
    * Get coins height by input.
    * @param {Input} input

lib/primitives/input.js

@@ -169,10 +169,11 @@ class Input extends bio.Struct {
    * for JSON serialization.
    * @param {Network} network
    * @param {Coin} coin
+   * @param {Path} path
    * @returns {Object}
    */
 
-  getJSON(network, coin) {
+  getJSON(network, coin, path) {
     network = Network.get(network);
 
     let addr;
@@ -187,7 +188,8 @@ class Input extends bio.Struct {
       witness: this.witness.toJSON(),
       sequence: this.sequence,
       address: addr,
-      coin: coin ? coin.getJSON(network, true) : undefined
+      coin: coin ? coin.getJSON(network, true) : undefined,
+      path: path ? path.getJSON(network) : undefined
     };
   }
 

lib/primitives/mtx.js

@@ -16,6 +16,8 @@ const Output = require('./output');
 const Coin = require('./coin');
 const Outpoint = require('./outpoint');
 const CoinView = require('../coins/coinview');
+const Path = require('../wallet/path');
+const WalletCoinView = require('../wallet/walletcoinview');
 const Address = require('./address');
 const consensus = require('../protocol/consensus');
 const policy = require('../protocol/policy');
@@ -1343,6 +1345,17 @@ class MTX extends TX {
       coin.index = prevout.index;
 
       this.view.addCoin(coin);
+
+      if (!input.path)
+        continue;
+
+      if(!(this.view instanceof WalletCoinView))
+        this.view = WalletCoinView.fromCoinView(this.view);
+
+      const outpoint = Outpoint.fromJSON(prevout);
+      const path = Path.fromJSON(input.path);
+
+      this.view.addPath(outpoint, path);
     }
 
     return this;

lib/primitives/tx.js

@@ -1748,7 +1748,8 @@ class TX extends bio.Struct {
       version: this.version,
       inputs: this.inputs.map((input) => {
         const coin = view ? view.getCoinFor(input) : null;
-        return input.getJSON(network, coin);
+        const path = view ? view.getPathFor(input) : null;
+        return input.getJSON(network, coin, path);
       }),
       outputs: this.outputs.map((output) => {
         return output.getJSON(network);

lib/wallet/http.js

@@ -1633,6 +1633,7 @@ class TransactionOptions {
     this.subtractFee = valid.bool('subtractFee');
     this.subtractIndex = valid.i32('subtractIndex');
     this.depth = valid.u32(['confirmations', 'depth']);
+    this.paths = valid.bool('paths');
     this.outputs = [];
 
     if (valid.has('outputs')) {

lib/wallet/path.js

@@ -9,6 +9,7 @@
 const assert = require('bsert');
 const bio = require('bufio');
 const Address = require('../primitives/address');
+const Network = require('../protocol/network');
 const {encoding} = bio;
 
 /**
@@ -212,14 +213,23 @@ class Path extends bio.Struct {
 
   /**
    * Convert path object to string derivation path.
+   * @param {String|Network?} network - Network type.
    * @returns {String}
    */
 
-  toPath() {
+  toPath(network) {
     if (this.keyType !== Path.types.HD)
       return null;
 
-    return `m/${this.account}'/${this.branch}/${this.index}`;
+    let prefix = 'm';
+
+    if (network) {
+      const purpose = 44;
+      network = Network.get(network);
+      prefix += `/${purpose}'/${network.keyPrefix.coinType}'`;
+    }
+
+    return `${prefix}/${this.account}'/${this.branch}/${this.index}`;
   }
 
   /**
@@ -233,18 +243,62 @@ class Path extends bio.Struct {
 
   /**
    * Convert path to a json-friendly object.
+   * @param {String|Network?} network - Network type.
    * @returns {Object}
    */
 
-  getJSON() {
+  getJSON(network) {
     return {
       name: this.name,
       account: this.account,
       change: this.branch === 1,
-      derivation: this.toPath()
+      derivation: this.toPath(network)
     };
   }
 
+  /**
+   * Inject properties from a json object.
+   * @param {Object} json
+   * @returns {Path}
+   */
+
+  static fromJSON(json) {
+    return new this().fromJSON(json);
+  }
+
+  /**
+   * Inject properties from a json object.
+   * @param {Object} json
+   * @returns {Path}
+   */
+
+  fromJSON(json) {
+    assert(json && typeof json === 'object');
+    assert(json.derivation && typeof json.derivation === 'string');
+
+    // Note: this object is mutated below.
+    const path = json.derivation.split('/');
+
+    // Note: "m/X'/X'/X'/X/X" or "m/X'/X/X".
+    assert (path.length === 4 || path.length === 6);
+
+    const index = parseInt(path.pop(), 10);
+    const branch = parseInt(path.pop(), 10);
+    const account = parseInt(path.pop(), 10);
+
+    assert(account === json.account);
+    assert(branch === 0 || branch === 1);
+    assert(Boolean(branch) === json.change);
+    assert((index >>> 0) === index);
+
+    this.name = json.name;
+    this.account = account;
+    this.branch = branch;
+    this.index = index;
+
+    return this;
+  }
+
   /**
    * Inspect the path.
    * @returns {String}

lib/wallet/paths.js

@@ -0,0 +1,93 @@
+/*!
+ * paths.js - paths object for hsd
+ * Copyright (c) 2019, Boyma Fahnbulleh (MIT License).
+ * https://github.com/handshake-org/hsd
+ */
+
+'use strict';
+
+const assert = require('bsert');
+
+/**
+ * Paths
+ * Represents the HD paths for coins in a single transaction.
+ * @alias module:wallet.Paths
+ * @property {Map[]} outputs - Paths.
+ */
+
+class Paths {
+  /**
+   * Create paths
+   * @constructor
+   */
+
+  constructor() {
+    this.paths = new Map();
+  }
+
+  /**
+   * Add a single entry to the collection.
+   * @param {Number} index
+   * @param {Path} path
+   * @returns {Path}
+   */
+
+  add(index, path) {
+    assert((index >>> 0) === index);
+    assert(path);
+    this.paths.set(index, path);
+    return path;
+  }
+
+  /**
+   * Test whether the collection has a path.
+   * @param {Number} index
+   * @returns {Boolean}
+   */
+
+  has(index) {
+    return this.paths.has(index);
+  }
+
+  /**
+   * Get a path.
+   * @param {Number} index
+   * @returns {Path|null}
+   */
+
+  get(index) {
+    return this.paths.get(index) || null;
+  }
+
+  /**
+   * Remove a path and return it.
+   * @param {Number} index
+   * @returns {Path|null}
+   */
+
+  remove(index) {
+    const path = this.get(index);
+
+    if (!path)
+      return null;
+
+    this.paths.delete(index);
+
+    return path;
+  }
+
+  /**
+   * Test whether there are paths.
+   * @returns {Boolean}
+   */
+
+  isEmpty() {
+    return this.paths.size === 0;
+  }
+}
+
+/*
+ * Expose
+ */
+
+module.exports = Paths;