Answers for "Galaxy A11"

Galaxy A11

val keyAlias = MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC)

Galaxy A11

// Custom Advanced Master Key
val advancedSpec = KeyGenParameterSpec.Builder(
    "master_key",
    KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT
).apply {
    setBlockModes(KeyProperties.BLOCK_MODE_GCM)
    setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_NONE)
    setKeySize(256)
    setUserAuthenticationRequired(true)
    setUserAuthenticationValidityDurationSeconds(15) // must be larger than 0
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
        setUnlockedDeviceRequired(true)
        setIsStrongBoxBacked(true)
    }
}.build()

val advancedKeyAlias = MasterKeys.getOrCreate(advancedSpec)

Galaxy A11

val secretFile = File(filesDir, "super_secret")
val encryptedFile = EncryptedFile.Builder(
    secretFile,
    applicationContext,
    advancedKeyAlias,
    FileEncryptionScheme.AES256_GCM_HKDF_4KB)
    .setKeysetAlias("file_key") // optional
    .setKeysetPrefName("secret_shared_prefs") // optional
    .build()

encryptedFile.openFileOutput().use { outputStream ->
    // Write data to your encrypted file
}

encryptedFile.openFileInput().use { inputStream ->
    // Read data from your encrypted file
}