README.md

Android Biometrics Integration Sample

This project provides a sample implementation for integrating biometric authentication in Android apps. It covers both normal and cryptographic biometric operations, serving as a practical guide for developers.

Overview

The application is structured into several main components, each handling different aspects of biometric integration:

Components

• Biometric Verification Callback: Interfaces to handle success, failure, and error events during biometric operations.
• CryptoBiometricsHelper: Manages cryptographic operations with biometric authentication.
• NormalBiometricHelper: Handles basic biometric authentication processes.

Key Components

BiometricVerificationCallback Interface

• onSuccess(result: String?): Triggered when biometric verification is successfully completed.
• onFailure(isLock: Boolean): Triggered when verification fails or is canceled, includes a flag for biometric lockout.
• onError(error: String): Called when an error occurs during biometric processing.

CryptoBiometricsHelper

Manages cryptographic operations using biometrics:

• requestBiometricsForEncryption(activity, key, data, callback): Starts an encryption process using biometrics.
• requestBiometricsForDecryption(activity, key, callback): Starts a decryption process using biometrics.
• encryptAndStoreBiometricData(context, authResult, data): Encrypts and securely stores data.

NormalBiometricHelper

Handles basic biometric authentication:

• isBiometricsAvailable(context): Checks if biometric authentication is available and enabled on the device.
• requestNormalBiometrics(activity, callback): Begins a biometric authentication process.

Usage Examples

Normal Biometric Authentication

if (NormalBiometricHelper.isBiometricsAvailable(context)) {
    NormalBiometricHelper.requestNormalBiometrics(activity, object : BiometricVerificationCallback {
        override fun onSuccess(result: String?) {
            // Handle success
        }

        override fun onFailure(isLock: Boolean) {
            // Handle failure
        }

        override fun onError(error: String) {
            // Handle error
        }
    })
}

Cryptographic Biometric Authentication

Encrypting Data

CryptoBiometricsHelper.requestBiometricsForEncryption(activity, "key_example", "data_to_encrypt", object : BiometricVerificationCallback {
    override fun onSuccess(result: String?) {
        // Data encrypted successfully
    }

    override fun onFailure(isLock: Boolean) {
        // Handle failure
    }

    override fun onError(error: String) {
        // Handle error
    }
})

Encrypting Data

CryptoBiometricsHelper.requestBiometricsForDecryption(activity, "key_example", object : BiometricVerificationCallback {
    override fun onSuccess(result: String?) {
        // Data decrypted successfully
    }

    override fun onFailure(isLock: Boolean) {
        // Handle failure
    }

    override fun onError(error: String) {
        // Handle error
    }
})