From a9aa213b212054e451f171818f721465fd7c1f02 Mon Sep 17 00:00:00 2001
From: Overtorment <overtorment@gmail.com>
Date: Tue, 8 Dec 2020 14:58:16 +0000
Subject: [PATCH] FIX: scan multisig cosigner in formats: plain Zpub, wallet
 descriptor

---
 class/multisig-cosigner.js            | 67 +++++++++++++++++++++++++++
 tests/unit/multisig-hd-wallet.test.js | 35 ++++++++++++++
 2 files changed, 102 insertions(+)

diff --git a/class/multisig-cosigner.js b/class/multisig-cosigner.js
index 348a86611..6cab04f26 100644
--- a/class/multisig-cosigner.js
+++ b/class/multisig-cosigner.js
@@ -1,3 +1,6 @@
+import b58 from 'bs58check';
+const HDNode = require('bip32');
+
 export class MultisigCosigner {
   constructor(data) {
     this._data = data;
@@ -7,6 +10,50 @@ export class MultisigCosigner {
     this._valid = false;
     this._cosigners = [];
 
+    // is it plain simple Zpub/Ypub/xpub?
+    if (data.startsWith('Zpub') && MultisigCosigner.isXpubValid(data)) {
+      this._fp = '00000000';
+      this._xpub = data;
+      this._path = "m/48'/0'/0'/2'";
+      this._valid = true;
+      this._cosigners = [true];
+      return;
+    } else if (data.startsWith('Ypub') && MultisigCosigner.isXpubValid(data)) {
+      this._fp = '00000000';
+      this._xpub = data;
+      this._path = "m/48'/0'/0'/1'";
+      this._valid = true;
+      this._cosigners = [true];
+      return;
+    } else if (data.startsWith('xpub') && MultisigCosigner.isXpubValid(data)) {
+      this._fp = '00000000';
+      this._xpub = data;
+      this._path = "m/45'";
+      this._valid = true;
+      this._cosigners = [true];
+      return;
+    }
+
+    // is it wallet descriptor?
+    if (data.startsWith('[')) {
+      const end = data.indexOf(']');
+      const part = data.substr(1, end - 1).replace(/[h]/g, "'");
+      this._fp = part.split('/')[0];
+      const xpub = data.substr(end + 1);
+
+      if (MultisigCosigner.isXpubValid(xpub)) {
+        this._xpub = xpub;
+        this._path = 'm';
+        for (let c = 0; c < part.split('/').length; c++) {
+          if (c === 0) continue;
+          this._path += '/' + part.split('/')[c];
+        }
+        this._cosigners = [true];
+        this._valid = true;
+        return;
+      }
+    }
+
     // is it cobo json?
     try {
       const json = JSON.parse(data);
@@ -47,6 +94,26 @@ export class MultisigCosigner {
     }
   }
 
+  static _zpubToXpub(zpub) {
+    let data = b58.decode(zpub);
+    data = data.slice(4);
+    data = Buffer.concat([Buffer.from('0488b21e', 'hex'), data]);
+
+    return b58.encode(data);
+  }
+
+  static isXpubValid(key) {
+    let xpub;
+
+    try {
+      xpub = MultisigCosigner._zpubToXpub(key);
+      HDNode.fromBase58(xpub);
+      return true;
+    } catch (_) {}
+
+    return false;
+  }
+
   static exportToJson(xfp, xpub, path) {
     return JSON.stringify({
       xfp: xfp,
diff --git a/tests/unit/multisig-hd-wallet.test.js b/tests/unit/multisig-hd-wallet.test.js
index 0d97b49ce..c36968f84 100644
--- a/tests/unit/multisig-hd-wallet.test.js
+++ b/tests/unit/multisig-hd-wallet.test.js
@@ -1582,6 +1582,41 @@ describe('multisig-cosigner', () => {
     assert.strictEqual(cosigner.howManyCosignersWeHave(), 1);
   });
 
+  it('can parse plain Zpub', () => {
+    const cosigner = new MultisigCosigner(Zpub1);
+    assert.ok(cosigner.isValid());
+    assert.strictEqual(cosigner.getFp(), '00000000');
+    assert.strictEqual(cosigner.getXpub(), Zpub1);
+    assert.strictEqual(cosigner.getPath(), "m/48'/0'/0'/2'");
+    assert.strictEqual(cosigner.howManyCosignersWeHave(), 1);
+  });
+
+  it('can parse wallet descriptor', () => {
+    let cosigner = new MultisigCosigner(
+      '[73c5da0a/48h/0h/0h/2h]Zpub74Jru6aftwwHxCUCWEvP6DgrfFsdA4U6ZRtQ5i8qJpMcC39yZGv3egBhQfV3MS9pZtH5z8iV5qWkJsK6ESs6mSzt4qvGhzJxPeeVS2e1zUG',
+    );
+    assert.ok(cosigner.isValid());
+    assert.strictEqual(cosigner.getFp(), '73c5da0a');
+    assert.strictEqual(
+      cosigner.getXpub(),
+      'Zpub74Jru6aftwwHxCUCWEvP6DgrfFsdA4U6ZRtQ5i8qJpMcC39yZGv3egBhQfV3MS9pZtH5z8iV5qWkJsK6ESs6mSzt4qvGhzJxPeeVS2e1zUG',
+    );
+    assert.strictEqual(cosigner.getPath(), "m/48'/0'/0'/2'");
+    assert.strictEqual(cosigner.howManyCosignersWeHave(), 1);
+
+    cosigner = new MultisigCosigner(
+      '[73c5da0a/48h/0h/0h/2h]xpub6DkFAXWQ2dHxq2vatrt9qyA3bXYU4ToWQwCHbf5XB2mSTexcHZCeKS1VZYcPoBd5X8yVcbXFHJR9R8UCVpt82VX1VhR28mCyxUFL4r6KFrf',
+    );
+    assert.ok(cosigner.isValid());
+    assert.strictEqual(cosigner.getFp(), '73c5da0a');
+    assert.strictEqual(
+      cosigner.getXpub(),
+      'xpub6DkFAXWQ2dHxq2vatrt9qyA3bXYU4ToWQwCHbf5XB2mSTexcHZCeKS1VZYcPoBd5X8yVcbXFHJR9R8UCVpt82VX1VhR28mCyxUFL4r6KFrf',
+    );
+    assert.strictEqual(cosigner.getPath(), "m/48'/0'/0'/2'");
+    assert.strictEqual(cosigner.howManyCosignersWeHave(), 1);
+  });
+
   it('cant parse bs', () => {
     const cosigner = new MultisigCosigner('asdfasdgsqwrgqwegq');
     assert.ok(!cosigner.isValid());