From de1e5558dc282f0be08f24397d1650014e071557 Mon Sep 17 00:00:00 2001
From: bip32jp <matsuringo.667@gmail.com>
Date: Fri, 2 Jan 2015 17:45:38 +0900
Subject: [PATCH] Force lower s value per BIP62

---
 js/coin.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/js/coin.js b/js/coin.js
index 4097d93..392a0e2 100644
--- a/js/coin.js
+++ b/js/coin.js
@@ -769,6 +769,12 @@
 					badrs++
 				} while (r.compareTo(BigInteger.ZERO) <= 0 || s.compareTo(BigInteger.ZERO) <= 0);
 
+				// Force lower s values per BIP62
+				var halfn = n.shiftRight(1);
+				if (s.compareTo(halfn) > 0) {
+					s = n.subtract(s);
+				};
+
 				var sig = serializeSig(r, s);
 				sig.push(parseInt(1, 10));