From 74cecb7fdfc0ff2a9889186eff0923a9526ccf16 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <braydon@bitpay.com>
Date: Wed, 29 Oct 2014 19:09:53 -0400
Subject: [PATCH] add padding of leading zeros

---
 lib/bitauth.js | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/bitauth.js b/lib/bitauth.js
index fb06aa2..83be89a 100644
--- a/lib/bitauth.js
+++ b/lib/bitauth.js
@@ -5,6 +5,18 @@ var bs58 = require('bs58');
 
 var BitAuth = {};
 
+/**
+ * Will add leading zeros to hex string
+ *
+ * @returns {String} A hex string
+ */
+BitAuth._addPaddingToHex = function(hex){
+  while( hex.length < 64 ){
+    hex = '0'+hex;
+  }
+  return hex;
+}
+
 /**
  * Will return a key pair and identity
  *
@@ -17,12 +29,13 @@ BitAuth.generateSin = function() {
 
   var keys = ecdsa.genKeyPair();
 
-  var publicKey = this.getPublicKeyFromPrivateKey(keys.getPrivate('hex'));
+  var privateKey = this._addPaddingToHex(keys.getPrivate('hex'));
+  var publicKey = this.getPublicKeyFromPrivateKey(privateKey);
   var sin = this.getSinFromPublicKey(publicKey);
 
   var sinObj = {
     created: new Date().getTime(),
-    priv: keys.getPrivate('hex'),
+    priv: privateKey,
     pub: publicKey,
     sin: sin
   }
@@ -43,8 +56,9 @@ BitAuth.getPublicKeyFromPrivateKey = function(privkey) {
 
   // compressed public key
   var pubKey = keys.getPublic();
-  var xbuf = new Buffer(pubKey.x.toString('hex'), 'hex');
-  var ybuf = new Buffer(pubKey.y.toString('hex'), 'hex');
+  var xbuf = new Buffer(this._addPaddingToHex(pubKey.x.toString('hex')), 'hex');
+  var ybuf = new Buffer(this._addPaddingToHex(pubKey.y.toString('hex')), 'hex');
+
   if (ybuf[ybuf.length-1] % 2) { //odd
     var pub = Buffer.concat([new Buffer([3]), xbuf]);
   }