fix message encryption/decryption

lib/client/api.js

@@ -15,7 +15,7 @@ var ServerCompromisedError = require('./servercompromisederror')
 
 var BASE_URL = 'http://localhost:3001/copay/api';
 
-var WALLET_CRITICAL_DATA = ['xPrivKey', 'm', 'publicKeyRing'];
+var WALLET_CRITICAL_DATA = ['xPrivKey', 'm', 'publicKeyRing', 'sharedEncryptingKey'];
 
 function _encryptProposalMessage(message, encryptingKey) {
   if (!message) return null;
@@ -24,7 +24,11 @@ function _encryptProposalMessage(message, encryptingKey) {
 
 function _decryptProposalMessage(message, encryptingKey) {
   if (!message) return '';
-  return WalletUtils.decryptMessage(message, encryptingKey);
+  try {
+    return WalletUtils.decryptMessage(message, encryptingKey);
+  } catch (ex) {
+    return '<ECANNOTDECRYPT>';
+  }
 };
 
 function _parseError(body) {
@@ -150,8 +154,9 @@ API.prototype._doGetRequest = function(url, data, cb) {
 
 API.prototype._initData = function(network, walletPrivKey, m, n) {
   var xPrivKey = new Bitcore.HDPrivateKey(network);
-  var signingPrivKey = (new Bitcore.HDPrivateKey(xPrivKey)).derive('m/1/0').privateKey.toWIF();
   var xPubKey = (new Bitcore.HDPublicKey(xPrivKey)).toString();
+  var signingPrivKey = (new Bitcore.HDPrivateKey(xPrivKey)).derive('m/1/0').privateKey;
+  var sharedEncryptingKey = Bitcore.crypto.Hash.sha256(signingPrivKey.toBuffer()).slice(0, 16).toString('base64');
   var copayerId = WalletUtils.xPubToCopayerId(xPubKey);
 
   var data = {
@@ -161,8 +166,9 @@ API.prototype._initData = function(network, walletPrivKey, m, n) {
     network: network,
     m: m,
     n: n,
-    signingPrivKey: signingPrivKey,
+    signingPrivKey: signingPrivKey.toWIF(),
     walletPrivKey: walletPrivKey.toWIF(),
+    sharedEncryptingKey: sharedEncryptingKey,
   };
   return data;
 };
@@ -280,8 +286,8 @@ API.prototype.getStatus = function(cb) {
     var url = '/v1/wallets/';
     self._doGetRequest(url, data, function(err, body) {
       _.each(body.pendingTxps, function(txp) {
-         txp.message = _decryptProposalMessage(txp.message, data.signingPrivKey);
-       });
+        txp.message = _decryptProposalMessage(txp.message, data.sharedEncryptingKey);
+      });
 
       return cb(err, body, data.copayerId);
     });
@@ -312,7 +318,7 @@ API.prototype.sendTxProposal = function(opts, cb) {
     var args = {
       toAddress: opts.toAddress,
       amount: amount,
-      message: _encryptProposalMessage(opts.message, data.signingPrivKey),
+      message: _encryptProposalMessage(opts.message, data.sharedEncryptingKey),
     };
     var hash = WalletUtils.getProposalHash(args.toAddress, args.amount, args.message);
     args.proposalSignature = WalletUtils.signMessage(hash, data.signingPrivKey);
@@ -417,7 +423,7 @@ API.prototype.getTxProposals = function(opts, cb) {
       if (err) return cb(err);
 
       _.each(txps, function(txp) {
-        txp.message = _decryptProposalMessage(txp.message, data.signingPrivKey);
+        txp.message = _decryptProposalMessage(txp.message, data.sharedEncryptingKey);
       });
       return cb(null, txps);
     });

lib/walletutils.js

@@ -83,20 +83,18 @@ WalletUtils.fromSecret = function(secret) {
 };
 
 
-WalletUtils.encryptMessage = function(message, privKey) {
-  var hash = sjcl.hash.sha256.hash(privKey);
-  var key = sjcl.codec.utf8String.toBits(hash);
-  key = sjcl.bitArray.clamp(key, 128);
+WalletUtils.encryptMessage = function(message, encryptingKey) {
+  var key = sjcl.codec.base64.toBits(encryptingKey);
+  //key = sjcl.bitArray.clamp(key, 128);
   return sjcl.encrypt(key, message, {
     ks: 128,
     iter: 1
   });
 };
 
-WalletUtils.decryptMessage = function(cyphertextJson, privKey) {
-  var hash = sjcl.hash.sha256.hash(privKey);
-  var key = sjcl.codec.utf8String.toBits(hash);
-  key = sjcl.bitArray.clamp(key, 128);
+WalletUtils.decryptMessage = function(cyphertextJson, encryptingKey) {
+  var key = sjcl.codec.base64.toBits(encryptingKey);
+  //key = sjcl.bitArray.clamp(key, 128);
   return sjcl.decrypt(key, cyphertextJson);
 };
 

test/integration/clientApi.js

@@ -177,7 +177,7 @@ describe('client API ', function() {
         statusCode: 200
       }, TestData.serverResponse.pendingTxs);
       client.request = request;
- 
+
       client.getTxProposals({}, function(err, x) {
         should.not.exist(err);
         x.length.should.equal(1);
@@ -194,6 +194,7 @@ describe('client API ', function() {
 
   describe('#sendTxProposal ', function() {
     it('should send tx proposal with encrypted message', function(done) {
+      client.storage.fs.readFile = sinon.stub().yields(null, JSON.stringify(TestData.storage.complete11));
       var response = {};
       var request = sinon.mock().yields(null, {
         statusCode: 200
@@ -210,7 +211,7 @@ describe('client API ', function() {
         callArgs.toAddress.should.equal(args.toAddress);
         callArgs.amount.should.equal(20000);
         callArgs.message.should.not.equal(args.message);
-        var decryptedMsg = WalletUtils.decryptMessage(callArgs.message, '42798f82c4ed9ace4d66335165071edf180e70bc0fc08dacb3e35185a2141d5b');
+        var decryptedMsg = WalletUtils.decryptMessage(callArgs.message, TestData.storage.complete11.sharedEncryptingKey);
         decryptedMsg.should.equal(args.message);
         done();
       });

test/integration/clienttestdata.js

@@ -28,17 +28,19 @@ var storage = {
     "publicKeyRing": ["xpub661MyMwAqRbcGzNFbVQLh6CV6ukHuhBn4Bf4CGrQ6pFfNNdJ3pxrEVDtFHGsTzyz6Py23FhP8GWAqew3PsvnstEs2iayH1PK5Mx1bSVSEAG", "xpub661MyMwAqRbcGH2FXudWPDdrRobZ9XWTGaz18AnN1gkG8QW9ZUcn63RcK5qJJ5DXYXeAWBNqprdvvg8VHA5twmBHCUc6gWygXkwmU1Dohwh"],
     "copayerId": "020b41cfea5fae42050580474a195a8385b093f291af4079759851d8819383a680",
     "signingPrivKey": "KyhU3befBaePqHuPQNNyY1XFUgnArR3GUKZpZwV5vS7u1pcR3uzB",
+    "sharedEncryptingKey": "ezDRS2NRchMJLf1IWtjL5A==",
     "network": "livenet"
   },
   complete11: {
-    "copayerId": "02da4d1bd797b41a5565fe54f22583051bd3c29dbbc86eedadb6af6e9200af1048",
-    "xPrivKey": "tprv8ZgxMBicQKsPeCyWCzmvnAkJUBEKpqggFmEmaR6CeyHeJj8oB8uFRWZonK7qLD1ih35tiRr1xnXg9a2rGLiYGQWVgvjhubzuUvVyanPXNuU",
-    "publicKeyRing": ["tpubD6NzVbkrYhZ4Xg1J6eSXBaQR3CkFzAsaq4qYrw8W5F639DPZoXiqc1BfxSR2J1muzEE2qq7rZEDUgwyuwv1nYQgA9uorLghrT76FE5CjAuz"],
+    "copayerId": "036ed70f51adf14e3e55aba727d28adec1851aff6865552aa9ec9b9dbafecd4a87",
+    "xPrivKey": "tprv8ZgxMBicQKsPdjYWSKKh8SuMZAQ6K3J6v5H3A8ZVyyvXk4h1xft3qeRTmCZbxQB77n3ndfF6G4AevqgpiAVuCmZqYURH3wzSQviTvP1nkYN",
+    "publicKeyRing": ["tpubD6NzVbkrYhZ4XCaJKxzHXrZU8Bv2UNV1VNspSeboQFivaYwnb4he293KwLPxnNNSBEj3RAE5EEaHqPWatzexGd613hGMLLQz5BEgjtpgWnZ"],
     "network": "testnet",
     "m": 1,
     "n": 1,
-    "signingPrivKey": "Kzs8tquNTCsxwbEB9RiSNmcti4QXaW1i9UyLBV329VM5zU7o5nGB",
-    "walletPrivKey": "L259i9W123MrrEjBUTzPVvo3ZMoJV26WB7Abr9LcVsiuWpj6sEL1"
+    "signingPrivKey": "KxyNf4A1Td61GMrnC6LNQYsfE9zKvgsFmmgkPYrPoJHva4j9YSL1",
+    "walletPrivKey": "L4JHs2ZggZkEuRLffH2WVe337nwZWMxytxViLLGyAfGREk6bUCXo",
+    "sharedEncryptingKey": "ezDRS2NRchMJLf1IWtjL5A=="
   },
 };
 
@@ -141,7 +143,7 @@ var serverResponse = {
     creatorId: '02da4d1bd797b41a5565fe54f22583051bd3c29dbbc86eedadb6af6e9200af1048',
     toAddress: 'n2TBMPzPECGUfcT2EByiTJ12TPZkhN2mN5',
     amount: 10000,
-    message: '{"iv":"Ij6LjNp6Cjlrpx1MklQk9A==","v":1,"iter":1,"ks":128,"ts":64,"mode":"ccm","adata":"","cipher":"aes","ct":"uyxcL8bBgRS0W2KA"}',
+    message: '{"iv":"vDH4J15lBiokSP+iUS4ofA==","v":1,"iter":1,"ks":128,"ts":64,"mode":"ccm","adata":"","cipher":"aes","ct":"X/vPh+vh/Qv8IRSx"}',
     changeAddress: '2Mu4nmHhBWFk766M4yXJi2oyi59HZLKHWqn',
     inputs: [{
       address: '2MvBhgsQX6EusXvNGdcjM5dschDkaos1uuk',

test/walletutils.js

@@ -68,7 +68,7 @@ describe('WalletUtils', function() {
 
   describe('#encryptMessage #decryptMessage round trip', function() {
     it('should encrypt and decrypt', function() {
-      var pwd = '0dea92f1df6675085b5cdd965487bb862f84f2755bcb56fa45dbf5b387a6c4a0';
+      var pwd = "ezDRS2NRchMJLf1IWtjL5A==";
       var ct = WalletUtils.encryptMessage('hello world', pwd);
       var msg = WalletUtils.decryptMessage(ct, pwd);
       msg.should.equal('hello world');