SecurePrefs: Encrypted Storage for Kotlin Multiplatform

SecurePrefs is an open-source library providing encrypted key-value storage.

It can be integrated seamlessly in Kotlin projects built with Kotlin Multiplatform, Kotlin/Native, and Kotlin Android plugins.

SecurePrefs allows storing key-value data in common code modules without any additional boilerplate code.

Supported platforms:

• Android (API >= 21)
• iOS (ios_arm64 and ios_x64 targets)

Download

To use this library in your project, add Netguru and Binryprefs maven urls to the repositories block:

repositories {
    maven { url "https://jitpack.io" }
}

Then add following dependencies to the common module build.gradle:

    sourceSets {
        commonMain {
            dependencies {
                implementation 'com.icecreamhappens.secureprefs:common:0.3.0'     
            }
        }
    }

Remember to enable GRADLE_METADATA in settings.gradle:

enableFeaturePreview('GRADLE_METADATA')

Usage

Just start with creating an instance of SecurePrefs class somewhere in your common module and enjoy! It's as simple as that. You don't have to initialize it by yourself nor to pass Android Context. Everything is done automatically.

val storage = SecurePrefs(name = "my_secret_storage")

The name parameter is optional. You can omit it if you want to use default storage. SecurePrefs allows you to store and persist multiple data types:

• String
• Int
• Long
• Float
• Double
• Boolean

If you want to store something, just call:

storage.putString(key = "someKey", value = "value")

If you want to get stored value - use:

storage.getString(key = "someKey", defaultValue = "default")

All get() functions will return defaultValue parameter if storage doesn't contain selected key.

You can get all keys stored in SecurePrefs storage by calling:

storage.getAll()

You can check if SecurePrefs storage contains selected key by calling:

storage.contains(key = "someKey")

You can also remove selected key from storage:

storage.remove(key = "someKey")

Last, but not least, you can remove all data stored in SecurePrefs storage:

storage.clear()

About

SecurePrefs allows to store key-value pairs in platform-specific way securely. Forked from Kissme to add api level 21 support and replace Android implementation with androidx.security.EncryptedSharedPreferences

Android

Android implementation uses androidx.security.EncryptedSharedPreferences

In order to acquire the application Context instance required for data storing operations the library registers an internal ContentProvider.

iOS

The iOS implementation is using native iOS Keychain. The Secure Enclave is a hardware-based key manager that's isolated from processor. It allows you to store, delete, fetch passwords and accounts. Keychain is simple wrapper build upon Security interface to store, save, and fetch not only passwords, but also accounts.

Running sample app

Sample app uses Maven Local for resolving SecurePrefs dependencies. Before running sample app you need to:

1. Build the library - ./gradlew build
2. Publish dependencies to Maven Local - ./gradlew publishToMavenLocal
3. Run selected library. If you want to run iOS app - you need to properly configure Xcode. Please check: https://kotlinlang.org/docs/tutorials/native/mpp-ios-android.html#setting-up-xcode before running iOS sample app.

License

Copyright 2018 Netguru

Copyright 2020 ATizik

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.