@nativescript/secure-storage

Secure Storage using SAMKeychain on iOS and Hawk on Android.

npm install @nativescript/secure-storage

API

set | setSync

// require the plugin
import { SecureStorage } from "@nativescript/secure-storage";

// instantiate the plugin
const secureStorage = new SecureStorage();

// async
secureStorage.set({
  key: "foo",
  value: "I was set at " + new Date()
}).then(success => console.log("Successfully set a value? " + success));

// sync
const success = secureStorage.setSync({
  key: "foo",
  value: "I was set at " + new Date()
});

get | getSync

Will return null if not found.

// async
secureStorage.get({
  key: "foo"
}).then(value => console.log("Got value: " + value));

// sync
const value = secureStorage.getSync({
  key: "foo"
});

remove | removeSync

// async
secureStorage.remove({
  key: "foo"
}).then(success => console.log("Successfully removed a value? " + success));

// sync
const success = secureStorage.removeSync({
  key: "foo"
});

removeAll | removeAllSync

// async
secureStorage.removeAll().then(success => console.log("Successfully removed a value? " + success));

// sync
const success = secureStorage.removeAllSync();

clearAllOnFirstRun | clearAllOnFirstRunSync

These functions can be used if you want to clear data when your app is reinstalled.

This is only really useful on iOS because if you write something (through this plugin) to the Keychain, this data won't be removed when the app is uninstalled. So the next time the same app is installed, it will find the data in the keychain.

So if you want to clear 'lingering' data from a previous install, make sure you run one of these methods before using other methods this plugin provides.

// async
secureStorage.clearAllOnFirstRun().then(success => {
    console.log(success ? "Successfully removed all data on the first run" : "Data not removed because this is not the first run");
});

// sync
const success = secureStorage.clearAllOnFirstRunSync();

isFirstRun | isFirstRunSync

As a bonus, you can piggyback the 'first run' mechanism to do anything you want when the plugin detects this is the first run (after an install or install-delete-reinstall).

// sync
if (secureStorage.isFirstRunSync()) {
  // do whatever you want
}

// async
secureStorage.isFirstRun().then(isFirst => {
  // if isFirst is true, do whatever you like
});

iOS Security++

By default the plugin uses kSecAttrAccessibleAlwaysThisDeviceOnly access control to the keychain. This means that the keychain value can be accessed even if the device is locked. If you want to enhance security and you do not need background access, or if you want to allow the value to be backed up and migrated to another device, you can use any of keys defined here and pass it when you create an instance of SecureStorage, for example

declare const kSecAttrAccessibleWhenUnlockedThisDeviceOnly; // This is needed in case you don't have tns-platform-declarations module installed. 
const secureStorage = new SecureStorage(kSecAttrAccessibleWhenUnlockedThisDeviceOnly);

iOS Simulator

Currently this plugin defaults to using NSUserDefaults on iOS Simulators. You can change this behaviour by providing disableFallbackToUserDefaults to the constructor of SecureStorage. This then uses the keychain instead of NSUserDefaults on simulators.

If you're running into issues similar to issue_10, consider using the default behaviour again.

iOS Keychain Access/App Groups

You can share secrets between iOS apps/extensions via Keychain access groups, or App Groups, see here for details.

To setup:

• Add a keychain access group entitlement to your app by adding an entry in the app/App_Resources/iOS/<someName>.entitlements file.

  e.g.

  <key>keychain-access-groups</key>
  <array>
    <string>$(AppIdentifierPrefix)com.my.app.sharedgroup</string>
  </array>

• Then in your app specify the accessGroup property when getting/setting values. e.g.

  import { SecureStorage } from "nativescript-secure-storage";
  export class MyComponent {
    secureStorage = new SecureStorage();
    // a method that can be called from your view
    setSecureValue() {
      this.secureStorage.set({
        accessGroup:"<TeamID>.com.my.app.sharedgroup",
        key: 'myKey',
        value: 'my value'
      }).then(success => { console.log(success)});
    }
  }

Credits

• On iOS we're leveraging the KeyChain using the SAMKeychain library (on the Simulator NSUserDefaults),
• On Android we're using Hawk library which internally uses Facebook conceal.
• Thanks, Prabu Devarrajan for adding the deleteAll function!
• Thank you Eddy Verbruggen for all the years of service and great work!

License

Apache License Version 2.0