1 files changed, 23 insertions, 0 deletions
diff --git a/app/scripts/lib/sig-util.js b/app/scripts/lib/sig-util.js
new file mode 100644
index 000000000..f8748f535
--- /dev/null
+++ b/app/scripts/lib/sig-util.js
@@ -0,0 +1,23 @@
+const ethUtil = require('ethereumjs-util')
+
+module.exports = {
+
+  concatSig: function (v, r, s) {
+    const rSig = ethUtil.fromSigned(r)
+    const sSig = ethUtil.fromSigned(s)
+    const vSig = ethUtil.bufferToInt(v)
+    const rStr = padWithZeroes(ethUtil.toUnsigned(rSig).toString('hex'), 64)
+    const sStr = padWithZeroes(ethUtil.toUnsigned(sSig).toString('hex'), 64)
+    const vStr = ethUtil.stripHexPrefix(ethUtil.intToHex(vSig))
+    return ethUtil.addHexPrefix(rStr.concat(sStr, vStr)).toString('hex')
+  },
+
+}
+
+function padWithZeroes (number, length) {
+  var myString = '' + number
+  while (myString.length < length) {
+    myString = '0' + myString
+  }
+  return myString
+}