key storage spotless

This commit is contained in:
nrobi144
2026-01-06 06:50:31 +02:00
parent 4339247815
commit df9d648988
5 changed files with 48 additions and 20 deletions
@@ -30,14 +30,17 @@ import kotlinx.coroutines.withContext
* Android implementation of SecureKeyStorage using EncryptedSharedPreferences
* backed by Android Keystore (AES-256-GCM, hardware-backed when available).
*/
actual class SecureKeyStorage(private val context: Context) {
actual class SecureKeyStorage(
private val context: Context,
) {
companion object {
private const val PREFS_NAME = "amethyst_secure_keys"
private const val KEY_PREFIX = "privkey_"
}
private val masterKey: MasterKey by lazy {
MasterKey.Builder(context, MasterKey.DEFAULT_MASTER_KEY_ALIAS)
MasterKey
.Builder(context, MasterKey.DEFAULT_MASTER_KEY_ALIAS)
.setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
.build()
}
@@ -52,7 +55,10 @@ actual class SecureKeyStorage(private val context: Context) {
)
}
actual suspend fun savePrivateKey(npub: String, privKeyHex: String) {
actual suspend fun savePrivateKey(
npub: String,
privKeyHex: String,
) {
withContext(Dispatchers.IO) {
try {
encryptedPrefs.edit().putString(KEY_PREFIX + npub, privKeyHex).apply()
@@ -34,7 +34,10 @@ expect class SecureKeyStorage {
* @param privKeyHex The private key in hexadecimal format
* @throws SecureStorageException if storage operation fails
*/
suspend fun savePrivateKey(npub: String, privKeyHex: String)
suspend fun savePrivateKey(
npub: String,
privKeyHex: String,
)
/**
* Retrieves a private key for the given npub.
@@ -66,4 +69,7 @@ expect class SecureKeyStorage {
/**
* Exception thrown when secure storage operations fail.
*/
class SecureStorageException(message: String, cause: Throwable? = null) : Exception(message, cause)
class SecureStorageException(
message: String,
cause: Throwable? = null,
) : Exception(message, cause)
@@ -58,7 +58,10 @@ actual class SecureKeyStorage {
private var keyringAvailable: Boolean = true
private var fallbackPassword: String? = null
actual suspend fun savePrivateKey(npub: String, privKeyHex: String) {
actual suspend fun savePrivateKey(
npub: String,
privKeyHex: String,
) {
withContext(Dispatchers.IO) {
try {
if (keyringAvailable) {
@@ -111,11 +114,13 @@ actual class SecureKeyStorage {
}
}
actual suspend fun hasPrivateKey(npub: String): Boolean =
getPrivateKey(npub) != null
actual suspend fun hasPrivateKey(npub: String): Boolean = getPrivateKey(npub) != null
// Keyring-based storage
private fun saveToKeyring(npub: String, privKeyHex: String) {
private fun saveToKeyring(
npub: String,
privKeyHex: String,
) {
val keyring = Keyring.create()
keyring.setPassword(SERVICE_NAME, npub, privKeyHex)
}
@@ -138,7 +143,10 @@ actual class SecureKeyStorage {
}
// Fallback encrypted file storage
private fun saveToFallback(npub: String, privKeyHex: String) {
private fun saveToFallback(
npub: String,
privKeyHex: String,
) {
val password = getFallbackPassword()
val encrypted = encryptData(privKeyHex, password)
@@ -184,12 +192,12 @@ actual class SecureKeyStorage {
val fallbackFile = getFallbackFile()
if (!fallbackFile.exists()) return emptyMap()
return fallbackFile.readLines()
return fallbackFile
.readLines()
.mapNotNull { line ->
val parts = line.split(":", limit = 2)
if (parts.size == 2) parts[0] to parts[1] else null
}
.toMap()
}.toMap()
}
private fun getFallbackFile(): File {
@@ -206,7 +214,10 @@ actual class SecureKeyStorage {
return fallbackPassword!!
}
private fun encryptData(plaintext: String, password: String): String {
private fun encryptData(
plaintext: String,
password: String,
): String {
val salt = ByteArray(16).apply { SecureRandom().nextBytes(this) }
val iv = ByteArray(IV_LENGTH).apply { SecureRandom().nextBytes(this) }
@@ -222,7 +233,10 @@ actual class SecureKeyStorage {
return Base64.getEncoder().encodeToString(combined)
}
private fun decryptData(ciphertext: String, password: String): String {
private fun decryptData(
ciphertext: String,
password: String,
): String {
val combined = Base64.getDecoder().decode(ciphertext)
val salt = combined.copyOfRange(0, 16)