From e6bcf1293408c22f053b5ab4ad0f024be90b4799 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <braydon@bitpay.com>
Date: Mon, 3 Nov 2014 12:05:33 -0500
Subject: [PATCH] fixed an issue with verifying a signature with a public key
 with leading zeros

---
 lib/bitauth.js       |  4 ++--
 test/test.bitauth.js | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/lib/bitauth.js b/lib/bitauth.js
index 082a4dc..5de5aa6 100644
--- a/lib/bitauth.js
+++ b/lib/bitauth.js
@@ -44,8 +44,8 @@ BitAuth.getPublicKeyFromPrivateKey = function(privkey) {
 
   // compressed public key
   var pubKey = keys.getPublic();
-  var xbuf = new Buffer(pubKey.x.toString('hex', 2), 'hex');
-  var ybuf = new Buffer(pubKey.y.toString('hex', 2), 'hex');
+  var xbuf = new Buffer(pubKey.x.toString('hex', 64), 'hex');
+  var ybuf = new Buffer(pubKey.y.toString('hex', 64), 'hex');
 
   if (ybuf[ybuf.length-1] % 2) { //odd
     var pub = Buffer.concat([new Buffer([3]), xbuf]);
diff --git a/test/test.bitauth.js b/test/test.bitauth.js
index f008fbc..8149c51 100644
--- a/test/test.bitauth.js
+++ b/test/test.bitauth.js
@@ -19,6 +19,9 @@ describe('bitauth', function() {
     sin: 'Tf3yr5tYvccKNVrE26BrPs6LWZRh8woHwjR'
   }
 
+  // a private key that will produce a public key with a leading zero
+  var privateKeyToZero = 'c6b7f6bfe5bb19b1e390e55ed4ba5df8af6068d0eb89379a33f9c19aacf6c08c';
+
   // keys generated
   var keys      = null;
 
@@ -99,6 +102,24 @@ describe('bitauth', function() {
       });
     });
 
+    it('should verify the signature with leading zero public key', function(done) {
+
+      var leadingZeroKeys = {
+        priv: privateKeyToZero,
+        pub: bitauth.getPublicKeyFromPrivateKey(privateKeyToZero)
+      };
+
+      signature = bitauth.sign(contract, leadingZeroKeys.priv);
+      bitauth.verifySignature(contract, leadingZeroKeys.pub, signature, function(err, valid){
+        should.not.exist(err);
+        should.exist(valid);
+        valid.should.equal(true);
+      });
+
+      done();
+
+    });
+
   });
 
   describe('#validateSinTrue', function() {