React Native Encrypted Storage

React Native wrapper around SharedPreferences and Keychain to provide a secure alternative to Async Storage.

Why ?

Async Storage is great but it lacks security. This is less than ideal when storing sensitive data such as access tokens, payment information and so on. This module aims to solve this problem by providing a wrapper around Android's SharedPreferences and iOS' Keychain , complete with support for TypeScript.

Installation

Via yarn

$ yarn add react-native-encrypted-storage

Via npm

$ npm install react-native-encrypted-storage

Linking

React Native 0.60+

Since version 0.60, React Native supports auto linking. This means no additional step is needed on your end.

React Native <= 0.59

$ react-native link react-native-encrypted-storage

Special note for iOS using cocoapods , run:

$ npx pod-install

Usage

This module exposes four (4) native functions to store, retrieve, remove and clear values. They can be used like so:

Import

import EncryptedStorage from ' react-native-encrypted-storage ' ;

Storing a value

async function storeUserSession ( ) { try { await EncryptedStorage . setItem ( " user_session " , JSON . stringify ( { age : 21 , token : " ACCESS_TOKEN " , username : " emeraldsanto " , languages : [ " fr " , " en " , " de " ] } ) ) ; } catch ( error ) { } }

Retrieving a value

async function retrieveUserSession ( ) { try { const session = await EncryptedStorage . getItem ( " user_session " ) ; if ( session !== undefined ) { } } catch ( error ) { } }

Removing a value

async function removeUserSession ( ) { try { await EncryptedStorage . removeItem ( " user_session " ) ; } catch ( error ) { } }

Clearing all previously saved values

async function clearStorage ( ) { try { await EncryptedStorage . clear ( ) ; } catch ( error ) { } }

Error handling

Take the removeItem example, an error can occur when trying to remove a value which does not exist, or for any other reason. This module forwards the native iOS Security framework error codes to help with debugging.

async function removeUserSession ( ) { try { await EncryptedStorage . removeItem ( " user_session " ) ; } catch ( error ) { console . log ( error . code ) ; } }

Note regarding Keychain persistence

You'll notice that the iOS Keychain is not cleared when your app is uninstalled, this is the expected behaviour. However, if you do want to achieve a different behaviour, you can use the below snippet to clear the Keychain on the first launch of your app.

static void ClearKeychainIfNecessary ( ) { if ( [ [ NSUserDefaults standardUserDefaults ] boolForKey : @" HAS_RUN_BEFORE " ] == NO ) { [ [ NSUserDefaults standardUserDefaults ] setBool : YES forKey : @" HAS_RUN_BEFORE " ] ; NSArray *secItemClasses = @ [ (__bridge id ) kSecClassGenericPassword , (__bridge id ) kSecClassInternetPassword , (__bridge id ) kSecClassCertificate , (__bridge id ) kSecClassKey , (__bridge id ) kSecClassIdentity ] ; for ( id secItemClass in secItemClasses) { NSDictionary *spec = @ { (__bridge id ) kSecClass : secItemClass } ; SecItemDelete ( (__bridge CFDictionaryRef)spec); } } } @ implementation AppDelegate - ( BOOL ) application : ( UIApplication * ) application didFinishLaunchingWithOptions : ( NSDictionary * ) launchOptions { ClearKeychainIfNecessary ( ); RCTBridge *bridge = [ [ RCTBridge alloc ] initWithDelegate : self launchOptions : launchOptions ] ; RCTRootView *rootView = [ [ RCTRootView alloc ] initWithBridge : bridge moduleName : @" APP_NAME " initialProperties : nil ] ; rootView . backgroundColor = [ UIColor colorWithRed : 1.0f green : 1.0f blue : 1.0f alpha : 1 ] ; self . window = [ [ UIWindow alloc ] initWithFrame : [ UIScreen mainScreen ] .bounds ] ; UIViewController *rootViewController = [ UIViewController new ] ; rootViewController . view = rootView; self . window . rootViewController = rootViewController; [ self .window makeKeyAndVisible ] ; return YES ; } @ end

License

MIT