get BIP32 working in the browser by exposing more crypto

Key.js

@@ -10,7 +10,12 @@ if (process.versions) {
   var ECKey = require('./browser/vendor-bundle.js').ECKey;
   var buffertools = require('buffertools');
 
-  var bufferToArray = function(buffer) {
+  var kSpec = function() {
+    this._pub = null;
+    this.compressed = true; // default
+  };
+
+  var bufferToArray = kSpec.bufferToArray = function(buffer) {
     var ret = [];
 
     var l = buffer.length;
@@ -21,11 +26,6 @@ if (process.versions) {
     return ret;
   }
 
-  var kSpec = function() {
-    this._pub = null;
-    this.compressed = true; // default
-  };
-
 
   Object.defineProperty(kSpec.prototype, 'public', {
     set: function(p){

Point.js

@@ -1,6 +1,20 @@
+"use strict";
+
 var imports = require('soop').imports();
-var Key = imports.Key || require('./Key');
+var Key = imports.Key || require('./Key'); 
 var bignum = imports.bignum || require('bignum');
+var assert = require('assert');
+
+//browser
+if (!process.versions) {
+  var ECKey = require('./browser/vendor-bundle.js').ECKey;
+  var ECPointFp = require('./browser/vendor-bundle.js').ECPointFp;
+  var ECFieldElementFp = require('./browser/vendor-bundle.js').ECFieldElementFp;
+  var getSECCurveByName = require('./browser/vendor-bundle.js').getSECCurveByName;
+  var BigInteger = require('./browser/vendor-bundle.js').BigInteger;
+  var should = require('chai').should();
+}
+
 
 //a point on the secp256k1 curve
 //x and y are bignums
@@ -27,6 +41,35 @@ Point.add = function(p1, p2) {
 
   //browser
   else {
+    var ecparams = getSECCurveByName('secp256k1');
+
+    var p1xhex = p1.x.toBuffer({size: 32}).toString('hex');
+    var p1x = new BigInteger(p1xhex, 16);
+    var p1yhex = p1.y.toBuffer({size: 32}).toString('hex');
+    var p1y = new BigInteger(p1yhex, 16);
+    var p1px = new ECFieldElementFp(ecparams.getCurve().getQ(), p1x);
+    var p1py = new ECFieldElementFp(ecparams.getCurve().getQ(), p1y);
+    var p1p = new ECPointFp(ecparams.getCurve(), p1px, p1py);
+
+    var p2xhex = p2.x.toBuffer({size: 32}).toString('hex');
+    var p2x = new BigInteger(p2xhex, 16);
+    var p2yhex = p2.y.toBuffer({size: 32}).toString('hex');
+    var p2y = new BigInteger(p2yhex, 16);
+    var p2px = new ECFieldElementFp(ecparams.getCurve().getQ(), p2x);
+    var p2py = new ECFieldElementFp(ecparams.getCurve().getQ(), p2y);
+    var p2p = new ECPointFp(ecparams.getCurve(), p2px, p2py);
+
+    var p = p1p.add(p2p);
+
+    var point = new Point();
+    var pointxbuf = new Buffer(p.getX().toBigInteger().toByteArrayUnsigned());
+    point.x = bignum.fromBuffer(pointxbuf, {size: pointxbuf.length});
+    assert(pointxbuf.length <= 32);
+    var pointybuf = new Buffer(p.getY().toBigInteger().toByteArrayUnsigned());
+    assert(pointybuf.length <= 32);
+    point.y = bignum.fromBuffer(pointybuf, {size: pointybuf.length});
+
+    return point;
   }
 
 };
@@ -49,6 +92,15 @@ Point.fromKey = function(key) {
 
   //browser
   else {
+    var point = new Point();
+    var pubKeyBuf = new Buffer(key.public);
+    var key2 = new ECKey();
+    key2.setCompressed(key.compressed);
+    key2.setPub(Key.bufferToArray(pubKeyBuf));
+    key2.setCompressed(false);
+    point.x = bignum.fromBuffer((new Buffer(key2.getPub())).slice(1, 33), {size: 32});
+    point.y = bignum.fromBuffer((new Buffer(key2.getPub())).slice(33, 65), {size: 32});
+    return point;
   }
 };
 
@@ -62,13 +114,24 @@ Point.prototype.toKey = function() {
     var key = new Key();
     key.compressed = false;
     var prefix = new Buffer([0x04]);
-    key.public = Buffer.concat([prefix, xbuf, ybuf]); //this is probably wrong
+    key.public = Buffer.concat([prefix, xbuf, ybuf]); //this might be wrong
     key.compressed = true;
     return key;
   }
 
   //browser
   else {
+    var xbuf = this.x.toBuffer({size: 32});
+    var ybuf = this.y.toBuffer({size: 32});
+    var key = new ECKey();
+    key.setCompressed(false);
+    var prefix = new Buffer([0x04]);
+    var pub = Buffer.concat([prefix, xbuf, ybuf]); //this might be wrong
+    key.setPub(Key.bufferToArray(pub));
+    key.setCompressed(true);
+    var key2 = new Key();
+    key2.public = new Buffer(key.getPub());
+    return key2;
   }
 };
 

browser/vendor/ec.js

@@ -314,3 +314,6 @@ ECCurveFp.prototype.equals = curveFpEquals;
 ECCurveFp.prototype.getInfinity = curveFpGetInfinity;
 ECCurveFp.prototype.fromBigInteger = curveFpFromBigInteger;
 ECCurveFp.prototype.decodePointHex = curveFpDecodePointHex;
+
+module.exports.ECPointFp = ECPointFp;
+module.exports.ECFieldElementFp = ECFieldElementFp;

browser/vendor/jsbn2.js

@@ -654,3 +654,5 @@ BigInteger.prototype.square = bnSquare;
 // int hashCode()
 // long longValue()
 // static BigInteger valueOf(long val)
+
+module.exports.BigInteger = BigInteger;

browser/vendor/sec.js

@@ -171,3 +171,5 @@ function getSECCurveByName(name) {
     if(name == "secp256r1") return secp256r1();
     return null;
 }
+
+module.exports.getSECCurveByName = getSECCurveByName;

test/test.BIP32.js

@@ -94,6 +94,7 @@ describe('BIP32', function() {
   });
 
   it("should get m/0'/1 ext. public key from m/0' public key from test vector 1", function() {
+  //TEST
     var bip32 = new BIP32(vector1_m_private);
     var child = bip32.derive("m/0'");
     var child_pub = new BIP32(child.extendedPublicKeyString());