From 5346a4922eb47a48084f56b440f48c438a2b781d Mon Sep 17 00:00:00 2001
From: mitchell <mitchelljfsimon@gmail.com>
Date: Sat, 13 Jul 2019 15:48:32 -0400
Subject: [PATCH] Refactor crypto utils and grpc credentials client

---
 client/lib/main.dart                          |  6 ++---
 .../repositories/grpc_credentials_client.dart |  6 ++---
 client/lib/utils/crypto.dart                  | 23 ++++++++-----------
 3 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/client/lib/main.dart b/client/lib/main.dart
index 4c84a88..89f7c4b 100644
--- a/client/lib/main.dart
+++ b/client/lib/main.dart
@@ -36,7 +36,7 @@ class Selfpass extends StatelessWidget {
               title = 'Hosts';
               builder = (BuildContext context) => Provider<CredentialsRepo>(
                     builder: (BuildContext context) =>
-                        GRPCCredentialsClient.cached(config: settings.arguments),
+                        GRPCCredentialsClient.getInstance(config: settings.arguments),
                     child: Home(),
                   );
               break;
@@ -45,7 +45,7 @@ class Selfpass extends StatelessWidget {
               title = 'Credentials';
               builder = (BuildContext context) => Provider<CredentialsRepo>(
                     builder: (BuildContext context) =>
-                        GRPCCredentialsClient.cached(),
+                        GRPCCredentialsClient.getInstance(),
                     child: Credentials(settings.arguments),
                   );
               break;
@@ -54,7 +54,7 @@ class Selfpass extends StatelessWidget {
               title = 'Credential';
               builder = (BuildContext context) => Provider<CredentialsRepo>(
                     builder: (BuildContext context) =>
-                        GRPCCredentialsClient.cached(),
+                        GRPCCredentialsClient.getInstance(),
                     child: Credential(settings.arguments),
                   );
               break;
diff --git a/client/lib/repositories/grpc_credentials_client.dart b/client/lib/repositories/grpc_credentials_client.dart
index 54206ed..42c3a7b 100644
--- a/client/lib/repositories/grpc_credentials_client.dart
+++ b/client/lib/repositories/grpc_credentials_client.dart
@@ -11,7 +11,7 @@ import '../types/connection_config.dart';
 import '../types/credential.dart';
 
 class GRPCCredentialsClient implements CredentialsRepo {
-  static GRPCCredentialsClient _cached;
+  static GRPCCredentialsClient _instance;
   grpc.CredentialsClient _client;
 
   GRPCCredentialsClient(ConnectionConfig config) {
@@ -32,8 +32,8 @@ class GRPCCredentialsClient implements CredentialsRepo {
     ));
   }
 
-  factory GRPCCredentialsClient.cached({ConnectionConfig config}) =>
-      config == null ? _cached : _cached = GRPCCredentialsClient(config);
+  factory GRPCCredentialsClient.getInstance({ConnectionConfig config}) =>
+      config == null ? _instance : _instance = GRPCCredentialsClient(config);
 
   Stream<Metadata> getAllMetadata(String sourceHost) {
     final request = grpc.SourceHostRequest();
diff --git a/client/lib/utils/crypto.dart b/client/lib/utils/crypto.dart
index ad572d6..833503b 100644
--- a/client/lib/utils/crypto.dart
+++ b/client/lib/utils/crypto.dart
@@ -1,6 +1,5 @@
 import 'dart:math';
 import 'dart:convert';
-import 'dart:typed_data';
 
 import 'package:crypt/crypt.dart';
 import 'package:encrypt/encrypt.dart';
@@ -12,7 +11,7 @@ String hashPassword(String password) {
 
   final random = Random.secure();
   final saltInts =
-      List<int>.generate(saltSize, (_) => random.nextInt(saltIntMax));
+  List<int>.generate(saltSize, (_) => random.nextInt(saltIntMax));
   final salt = base64.encode(saltInts);
 
   return Crypt.sha256(password, salt: salt).toString();
@@ -21,20 +20,18 @@ String hashPassword(String password) {
 bool matchHashedPassword(String hashedPassword, String password) =>
     Crypt(hashedPassword).match(password);
 
-String decryptPassword(String masterpass, privateKey, ciphertext) {
-  final key =
-      PBKDF2().generateKey(masterpass, privateKey, pbkdf2Rounds, keySize);
+String decryptPassword(String masterpass, privateKey, cipherText) {
+  final key = PBKDF2().generateKey(
+    masterpass, privateKey, pbkdf2Rounds, keySize,
+  );
 
-  var cipherbytes = base64.decode(ciphertext);
-  final iv =
-      IV(Uint8List.fromList(cipherbytes.getRange(0, aesBlockSize).toList()));
-
-  cipherbytes = Uint8List.fromList(
-      cipherbytes.getRange(aesBlockSize, cipherbytes.length).toList());
+  var cipherBytes = base64.decode(cipherText);
+  final ivBytes = cipherBytes.sublist(0, aesBlockSize);
+  cipherBytes = cipherBytes.sublist(aesBlockSize);
 
+  final iv = IV(ivBytes);
   final encrypter = Encrypter(AES(Key(key), mode: AESMode.cbc));
-
-  return encrypter.decrypt(Encrypted(cipherbytes), iv: iv);
+  return encrypter.decrypt(Encrypted(cipherBytes), iv: iv);
 }
 
 const pbkdf2Rounds = 4096;