Merge pull request #305 from maraoz/refactor/improve-BIP32

Refactor/improve bip32 and add test

Gruntfile.js

@@ -26,7 +26,7 @@ module.exports = function(grunt) {
         tasks: ['markdown']
       },
       scripts: {
-        files: ['**/*.js', '**/*.html', '!**/node_modules/**', '!browser/bundle.js', '!browser/testdata.js', '!browser/vendor-bundle.js'],
+        files: ['**/*.js', '**/*.html', '!**/node_modules/**', '!browser/bundle.js', '!browser/testdata.js', '!browser/vendor-bundle.js', '!docs/**'],
         tasks: ['shell'],
       },
     },

lib/BIP32.js

@@ -7,8 +7,8 @@ var SecureRandom = imports.SecureRandom || require('./SecureRandom');
 var bignum = imports.bignum || require('./Bignum');
 var networks = require('../networks');
 
-var secp256k1_n = new bignum("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141", 16);
+var secp256k1_n = new bignum('FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141', 16);
-var secp256k1_Gx = new bignum("79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798", 16);
+var secp256k1_Gx = new bignum('79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798', 16);
 
 /*
 random new BIP32: new BIP32();
@@ -20,9 +20,9 @@ var BIP32 = function(bytes) {
     bytes = 'livenet';
     this.version = networks['livenet'].bip32privateVersion;
   }
-  else if (bytes == 'testnet')
+  else if (bytes == 'testnet') {
     this.version = networks['testnet'].bip32privateVersion;
-
+  }
   if (bytes == 'livenet' || bytes == 'testnet') {
     this.depth = 0x00;
     this.parentFingerprint = new Buffer([0, 0, 0, 0]);
@@ -37,17 +37,17 @@ var BIP32 = function(bytes) {
   }
   
   // decode base58
-  if (typeof bytes === "string") {
+  if (typeof bytes === 'string') {
     var decoded = base58.decode(bytes);
     if (decoded.length != 82)
-      throw new Error("Not enough data");
+      throw new Error('Not enough data, expected 82 and received '+decoded.length);
     var checksum = decoded.slice(78, 82);
     bytes = decoded.slice(0, 78);
 
     var hash = coinUtil.sha256(coinUtil.sha256(bytes));
 
     if (hash[0] != checksum[0] || hash[1] != checksum[1] || hash[2] != checksum[2] || hash[3] != checksum[3]) {
-      throw new Error("Invalid checksum");
+      throw new Error('Invalid checksum');
     }
   }
 
@@ -63,7 +63,7 @@ BIP32.seed = function(bytes, network) {
     bytes = new Buffer(bytes, 'hex'); //if not buffer, assume hex
   if (bytes.length < 128/8)
     return false; //need more entropy
-  var hash = coinUtil.sha512hmac(bytes, new Buffer("Bitcoin seed"));
+  var hash = coinUtil.sha512hmac(bytes, new Buffer('Bitcoin seed'));
 
   var bip32 = new BIP32(null);
   bip32.depth = 0x00;
@@ -85,7 +85,7 @@ BIP32.seed = function(bytes, network) {
 
 BIP32.prototype.initFromBytes = function(bytes) {
   // Both pub and private extended keys are 78 bytes
-  if(bytes.length != 78) throw new Error("not enough data");
+  if(bytes.length != 78) throw new Error('not enough data');
 
   this.version      = u32(bytes.slice(0, 4));
   this.depth        = u8(bytes.slice(4, 5));
@@ -116,7 +116,7 @@ BIP32.prototype.initFromBytes = function(bytes) {
     this.pubKeyHash = coinUtil.sha256ripe160(this.eckey.public);
     this.hasPrivateKey = false;
   } else {
-    throw new Error("Invalid key");
+    throw new Error('Invalid key');
   }
 
   this.buildExtendedPublicKey();
@@ -137,7 +137,7 @@ BIP32.prototype.buildExtendedPublicKey = function() {
     v = networks['testnet'].bip32publicVersion;
     break;
    default:
-    throw new Error("Unknown version");
+    throw new Error('Unknown version');
   }
 
   // Version
@@ -158,15 +158,15 @@ BIP32.prototype.buildExtendedPublicKey = function() {
 }
 
 BIP32.prototype.extendedPublicKeyString = function(format) {
-  if (format === undefined || format === "base58") {
+  if (format === undefined || format === 'base58') {
     var hash = coinUtil.sha256(coinUtil.sha256(this.extendedPublicKey));
     var checksum = hash.slice(0, 4);
     var data = Buffer.concat([this.extendedPublicKey, checksum]);
     return base58.encode(data);
-  } else if (format === "hex") {
+  } else if (format === 'hex') {
     return this.extendedPublicKey.toString('hex');;
   } else {
-    throw new Error("bad format");
+    throw new Error('bad format');
   }
 }
 
@@ -194,15 +194,15 @@ BIP32.prototype.buildExtendedPrivateKey = function() {
 }
 
 BIP32.prototype.extendedPrivateKeyString = function(format) {
-  if (format === undefined || format === "base58") {
+  if (format === undefined || format === 'base58') {
     var hash = coinUtil.sha256(coinUtil.sha256(this.extendedPrivateKey));
     var checksum = hash.slice(0, 4);
     var data = Buffer.concat([this.extendedPrivateKey, checksum]);
     return base58.encode(data);
-  } else if (format === "hex") {
+  } else if (format === 'hex') {
     return this.extendedPrivateKey.toString('hex');
   } else {
-    throw new Error("bad format");
+    throw new Error('bad format');
   }
 }
 
@@ -219,7 +219,7 @@ BIP32.prototype.derive = function(path) {
     var c = e[i];
 
     if (i == 0 ) {
-      if (c != 'm') throw new Error("invalid path");
+      if (c != 'm') throw new Error('invalid path');
       continue;
     }
 
@@ -250,7 +250,7 @@ BIP32.prototype.deriveChild = function(i) {
      this.version == networks['testnet'].bip32privateVersion  );
 
   if (usePrivate && (!this.hasPrivateKey || !isPrivate))
-    throw new Error("Cannot do private key derivation without private key");
+    throw new Error('Cannot do private key derivation without private key');
 
   var ret = null;
   if (this.hasPrivateKey) {
@@ -323,7 +323,7 @@ BIP32.prototype.deriveChild = function(i) {
 
 function uint(f, size) {
   if (f.length < size)
-    throw new Error("not enough data");
+    throw new Error('not enough data');
   var n = 0;
   for (var i = 0; i < size; i++) {
     n *= 256;

test/test.BIP32.js

@@ -291,7 +291,19 @@ describe('BIP32', function() {
       bip32.extendedPrivateKeyString().should.equal(vector2_m_private);
       bip32.extendedPublicKeyString().should.equal(vector2_m_public);
     });
+  });
 
+  describe('testnet', function() {
+    it('should initialize a new BIP32 correctly from a random BIP32', function() {
+      var b1 = new BIP32('testnet');
+      var b2 = new BIP32(b1.extendedPublicKeyString());
+      b2.extendedPublicKeyString().should.equal(b1.extendedPublicKeyString());
+    });
+
+    it('should generate valid ext pub key for testnet', function() {
+      var b = new BIP32('testnet');
+      b.extendedPublicKeyString().substring(0,4).should.equal('tpub');
+    });
   });
 
 });