packages/native_crypto_android/android/build.gradle

@@ -47,4 +47,5 @@ android {
 
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation 'androidx.documentfile:documentfile:1.0.1'
 }

packages/native_crypto_android/android/src/main/java/fr/pointcheval/native_crypto_android/GeneratedAndroidNativeCrypto.java

@@ -4,7 +4,7 @@
 // license that can be found in the LICENSE file or at
 // https://opensource.org/licenses/MIT.
 // --
-// Autogenerated from Pigeon (v9.0.0), do not edit directly.
+// Autogenerated from Pigeon (v9.2.0), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 
 package fr.pointcheval.native_crypto_android;
@@ -26,15 +26,40 @@ import java.util.List;
 import java.util.Map;
 
 /** Generated class from Pigeon. */
-@SuppressWarnings({"unused", "unchecked", "CodeBlock2Expr", "RedundantSuppression"})
+@SuppressWarnings({"unused", "unchecked", "CodeBlock2Expr", "RedundantSuppression", "serial"})
 public class GeneratedAndroidNativeCrypto {
+
+  /** Error class for passing custom error details to Flutter via a thrown PlatformException. */
+  public static class FlutterError extends RuntimeException {
+
+    /** The error code. */
+    public final String code;
+
+    /** The error details. Must be a datatype supported by the api codec. */
+    public final Object details;
+
+    public FlutterError(@NonNull String code, @Nullable String message, @Nullable Object details) 
+    {
+      super(message);
+      this.code = code;
+      this.details = details;
+    }
+  }
+
   @NonNull
   private static ArrayList<Object> wrapError(@NonNull Throwable exception) {
     ArrayList<Object> errorList = new ArrayList<Object>(3);
+    if (exception instanceof FlutterError) {
+      FlutterError error = (FlutterError) exception;
+      errorList.add(error.code);
+      errorList.add(error.getMessage());
+      errorList.add(error.details);
+    } else {
       errorList.add(exception.toString());
       errorList.add(exception.getClass().getSimpleName());
       errorList.add(
         "Cause: " + exception.getCause() + ", Stacktrace: " + Log.getStackTraceString(exception));
+    }
     return errorList;
   }
 
@@ -1339,16 +1364,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 HashRequest requestArg = (HashRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   HashResponse output = api.hash(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1366,16 +1388,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 HmacRequest requestArg = (HmacRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   HmacResponse output = api.hmac(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1393,16 +1412,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 GenerateSecureRandomRequest requestArg = (GenerateSecureRandomRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   GenerateSecureRandomResponse output = api.generateSecureRandom(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1420,16 +1436,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 Pbkdf2Request requestArg = (Pbkdf2Request) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   Pbkdf2Response output = api.pbkdf2(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1447,16 +1460,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 EncryptRequest requestArg = (EncryptRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   EncryptResponse output = api.encrypt(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1474,16 +1484,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 DecryptRequest requestArg = (DecryptRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   DecryptResponse output = api.decrypt(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1501,16 +1508,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 EncryptFileRequest requestArg = (EncryptFileRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   EncryptFileResponse output = api.encryptFile(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1528,16 +1532,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 DecryptFileRequest requestArg = (DecryptFileRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   DecryptFileResponse output = api.decryptFile(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }
@@ -1555,16 +1556,13 @@ public class GeneratedAndroidNativeCrypto {
           channel.setMessageHandler(
               (message, reply) -> {
                 ArrayList<Object> wrapped = new ArrayList<Object>();
-                try {
                 ArrayList<Object> args = (ArrayList<Object>) message;
-                  assert args != null;
                 EncryptWithIVRequest requestArg = (EncryptWithIVRequest) args.get(0);
-                  if (requestArg == null) {
-                    throw new NullPointerException("requestArg unexpectedly null.");
-                  }
+                try {
                   EncryptResponse output = api.encryptWithIV(requestArg);
                   wrapped.add(0, output);
-                } catch (Error | RuntimeException exception) {
+                }
+ catch (Throwable exception) {
                   ArrayList<Object> wrappedError = wrapError(exception);
                   wrapped = wrappedError;
                 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/NativeCrypto.kt

@@ -0,0 +1,118 @@
+package fr.pointcheval.native_crypto_android
+
+import android.content.Context
+import fr.pointcheval.native_crypto_android.ciphers.AES
+import fr.pointcheval.native_crypto_android.kdf.Pbkdf2
+import fr.pointcheval.native_crypto_android.utils.FileParameters
+import fr.pointcheval.native_crypto_android.utils.HashAlgorithmParser
+import java.security.SecureRandom
+
+class NativeCrypto(private val context: Context) : NativeCryptoAPI {
+    override fun hash(data: ByteArray, algorithm: HashAlgorithm): ByteArray? {
+        val md = HashAlgorithmParser.getMessageDigest(algorithm)
+
+        return md.digest(data)
+    }
+
+    override fun hmac(data: ByteArray, key: ByteArray, algorithm: HashAlgorithm): ByteArray? {
+        val mac = HashAlgorithmParser.getMac(algorithm)
+        val secretKey = javax.crypto.spec.SecretKeySpec(key, mac.algorithm)
+        mac.init(secretKey)
+
+        return mac.doFinal(data)
+    }
+
+    override fun generateSecureRandom(length: Long): ByteArray {
+        val bytes = ByteArray(length.toInt())
+        SecureRandom.getInstanceStrong().nextBytes(bytes)
+
+        return bytes
+    }
+
+    override fun pbkdf2(
+        password: ByteArray,
+        salt: ByteArray,
+        length: Long,
+        iterations: Long,
+        algorithm: HashAlgorithm
+    ): ByteArray? {
+        val pbkdf2 = Pbkdf2(length.toInt(), iterations.toInt(), algorithm)
+        pbkdf2.init(password, salt)
+
+        return pbkdf2.derive()
+    }
+
+    override fun encrypt(
+        plainText: ByteArray,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): ByteArray {
+        // For now, only AES is supported
+        val aes = AES()
+
+        return aes.encrypt(plainText, key, null)
+    }
+
+    override fun encryptWithIV(
+        plainText: ByteArray,
+        iv: ByteArray,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): ByteArray {
+        // For now, only AES is supported
+        val aes = AES()
+
+        return aes.encrypt(plainText, key, iv)
+    }
+
+    override fun decrypt(
+        cipherText: ByteArray,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): ByteArray {
+        // For now, only AES is supported
+        val aes = AES()
+
+        return aes.decrypt(cipherText, key)
+    }
+
+    override fun encryptFile(
+        plainTextPath: String,
+        cipherTextPath: String,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): Boolean {
+        // For now, only AES is supported
+        val aes = AES()
+        val params = FileParameters(context, plainTextPath, cipherTextPath)
+
+        return aes.encryptFile(params, key, null)
+    }
+
+    override fun encryptFileWithIV(
+        plainTextPath: String,
+        cipherTextPath: String,
+        iv: ByteArray,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): Boolean {
+        // For now, only AES is supported
+        val aes = AES()
+        val params = FileParameters(context, plainTextPath, cipherTextPath)
+
+        return aes.encryptFile(params, key, iv)
+    }
+
+    override fun decryptFile(
+        cipherTextPath: String,
+        plainTextPath: String,
+        key: ByteArray,
+        algorithm: CipherAlgorithm
+    ): Boolean {
+        // For now, only AES is supported
+        val aes = AES()
+        val params = FileParameters(context, plainTextPath, cipherTextPath)
+
+        return aes.decryptFile(params, key)
+    }
+}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/NativeCryptoAndroidPlugin.kt

@@ -1,160 +1,19 @@
 package fr.pointcheval.native_crypto_android
 
-import androidx.annotation.NonNull
-import fr.pointcheval.native_crypto_android.interfaces.Cipher
-import fr.pointcheval.native_crypto_android.kdf.Pbkdf2
-import fr.pointcheval.native_crypto_android.keys.SecretKey
-import fr.pointcheval.native_crypto_android.utils.CipherAlgorithm
-import fr.pointcheval.native_crypto_android.utils.Constants
-import fr.pointcheval.native_crypto_android.utils.HashAlgorithm
-import fr.pointcheval.native_crypto_android.utils.Task
 import io.flutter.embedding.engine.plugins.FlutterPlugin
-import io.flutter.plugin.common.MethodCall
-import io.flutter.plugin.common.MethodChannel
-import io.flutter.plugin.common.MethodChannel.MethodCallHandler
-import io.flutter.plugin.common.MethodChannel.Result
-import java.util.*
 
 /** NativeCryptoAndroidPlugin */
-class NativeCryptoAndroidPlugin : FlutterPlugin, MethodCallHandler {
-    /// The MethodChannel that will the communication between Flutter and native Android
-    ///
-    /// This local reference serves to register the plugin with the Flutter Engine and unregister it
-    /// when the Flutter Engine is detached from the Activity
-    private lateinit var channel: MethodChannel
-    private val name = "plugins.hugop.cl/native_crypto"
+class NativeCryptoAndroidPlugin : FlutterPlugin {
+    private var nativeCrypto: NativeCrypto? = null
 
-    private var cipherInstance: Cipher? = null
-
-    override fun onAttachedToEngine(@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {
-        channel = MethodChannel(flutterPluginBinding.binaryMessenger, name)
-        channel.setMethodCallHandler(this)
+    override fun onAttachedToEngine(flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {
+        val context = flutterPluginBinding.applicationContext
+        nativeCrypto = NativeCrypto(context)
+        NativeCryptoAPI.setUp(flutterPluginBinding.binaryMessenger, nativeCrypto)
     }
 
-    override fun onDetachedFromEngine(@NonNull binding: FlutterPlugin.FlutterPluginBinding) {
-        channel.setMethodCallHandler(null)
-    }
-
-    override fun onMethodCall(@NonNull call: MethodCall, @NonNull result: Result) {
-        lateinit var methodCallTask: Task<*>
-
-        when (call.method) {
-            "digest" -> methodCallTask = handleDigest(call.arguments())
-            "generateSecretKey" -> methodCallTask = handleGenerateSecretKey(call.arguments())
-            "pbkdf2" -> methodCallTask = handlePbkdf2(call.arguments())
-            "encryptAsList" -> methodCallTask = handleEncryptAsList(call.arguments())
-            "decryptAsList" -> methodCallTask = handleDecryptAsList(call.arguments())
-            "encrypt" -> methodCallTask = handleCrypt(call.arguments(), true)
-            "decrypt" -> methodCallTask = handleCrypt(call.arguments(), false)
-            else -> result.notImplemented()
-        }
-
-        methodCallTask.call()
-
-        methodCallTask.finalize { task ->
-            if (task.isSuccessful()) {
-                result.success(task.getResult())
-            } else {
-                val exception: Exception = task.getException()
-                val message = exception.message
-                result.error("native_crypto", message, null)
-            }
-        }
-    }
-
-    private fun handleDigest(arguments: Map<String, Any>?): Task<ByteArray> {
-        return Task {
-            val data: ByteArray =
-                Objects.requireNonNull(arguments?.get(Constants.DATA)) as ByteArray
-            val algorithm: String =
-                Objects.requireNonNull(arguments?.get(Constants.ALGORITHM)) as String
-            HashAlgorithm.digest(data, algorithm)
-        }
-    }
-
-    private fun handleGenerateSecretKey(arguments: Map<String, Any>?): Task<ByteArray> {
-        return Task {
-            val bitsCount: Int = Objects.requireNonNull(arguments?.get(Constants.BITS_COUNT)) as Int
-            SecretKey.fromSecureRandom(bitsCount).bytes
-        }
-    }
-
-    private fun handlePbkdf2(arguments: Map<String, Any>?): Task<ByteArray> {
-        return Task {
-            val password: String =
-                Objects.requireNonNull(arguments?.get(Constants.PASSWORD)) as String
-            val salt: String = Objects.requireNonNull(arguments?.get(Constants.SALT)) as String
-            val keyBytesCount: Int =
-                Objects.requireNonNull(arguments?.get(Constants.KEY_BYTES_COUNT)) as Int
-            val iterations: Int =
-                Objects.requireNonNull(arguments?.get(Constants.ITERATIONS)) as Int
-            val algorithm: String =
-                Objects.requireNonNull(arguments?.get(Constants.ALGORITHM)) as String
-
-            val pbkdf2: Pbkdf2 = Pbkdf2(keyBytesCount, iterations, HashAlgorithm.valueOf(algorithm))
-            pbkdf2.init(password, salt)
-
-            pbkdf2.derive().bytes
-        }
-    }
-
-    private fun lazyLoadCipher(cipherAlgorithm: CipherAlgorithm) {
-        if (cipherInstance == null) {
-            cipherInstance = cipherAlgorithm.getCipher()
-        } else {
-            if (cipherInstance!!.algorithm != cipherAlgorithm) {
-                cipherInstance = cipherAlgorithm.getCipher()
-            }
-        }
-    }
-
-    private fun handleEncryptAsList(arguments: Map<String, Any>?): Task<List<ByteArray>> {
-        return Task {
-            val data: ByteArray =
-                Objects.requireNonNull(arguments?.get(Constants.DATA)) as ByteArray
-            val key: ByteArray = Objects.requireNonNull(arguments?.get(Constants.KEY)) as ByteArray
-            val algorithm: String =
-                Objects.requireNonNull(arguments?.get(Constants.ALGORITHM)) as String
-
-            val cipherAlgorithm: CipherAlgorithm = CipherAlgorithm.valueOf(algorithm)
-            lazyLoadCipher(cipherAlgorithm)
-
-            cipherInstance!!.encryptAsList(data, key)
-        }
-    }
-
-    private fun handleDecryptAsList(arguments: Map<String, Any>?): Task<ByteArray> {
-        return Task {
-            val data: List<ByteArray> =
-                Objects.requireNonNull(arguments?.get(Constants.DATA)) as List<ByteArray>
-            val key: ByteArray = Objects.requireNonNull(arguments?.get(Constants.KEY)) as ByteArray
-            val algorithm: String =
-                Objects.requireNonNull(arguments?.get(Constants.ALGORITHM)) as String
-
-            val cipherAlgorithm: CipherAlgorithm = CipherAlgorithm.valueOf(algorithm)
-            lazyLoadCipher(cipherAlgorithm)
-
-            cipherInstance!!.decryptAsList(data, key)
-        }
-    }
-
-    // **EN**Crypt and **DE**Crypt
-    private fun handleCrypt(arguments: Map<String, Any>?, forEncryption: Boolean): Task<ByteArray> {
-        return Task {
-            val data: ByteArray =
-                Objects.requireNonNull(arguments?.get(Constants.DATA)) as ByteArray
-            val key: ByteArray = Objects.requireNonNull(arguments?.get(Constants.KEY)) as ByteArray
-            val algorithm: String =
-                Objects.requireNonNull(arguments?.get(Constants.ALGORITHM)) as String
-
-            val cipherAlgorithm: CipherAlgorithm = CipherAlgorithm.valueOf(algorithm)
-            lazyLoadCipher(cipherAlgorithm)
-
-            if (forEncryption) {
-                cipherInstance!!.encrypt(data, key)
-            } else {
-                cipherInstance!!.decrypt(data, key)
-            }
-        }
+    override fun onDetachedFromEngine(binding: FlutterPlugin.FlutterPluginBinding) {
+        NativeCryptoAPI.setUp(binding.binaryMessenger, null)
+        nativeCrypto = null
     }
 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/Pigeon.kt

@@ -0,0 +1,300 @@
+// Copyright 2019-2023 Hugo Pointcheval
+// 
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+// --
+// Autogenerated from Pigeon (v9.2.0), do not edit directly.
+// See also: https://pub.dev/packages/pigeon
+
+package fr.pointcheval.native_crypto_android
+
+import android.util.Log
+import io.flutter.plugin.common.BasicMessageChannel
+import io.flutter.plugin.common.BinaryMessenger
+import io.flutter.plugin.common.MessageCodec
+import io.flutter.plugin.common.StandardMessageCodec
+import java.io.ByteArrayOutputStream
+import java.nio.ByteBuffer
+
+private fun wrapResult(result: Any?): List<Any?> {
+  return listOf(result)
+}
+
+private fun wrapError(exception: Throwable): List<Any?> {
+  if (exception is FlutterError) {
+    return listOf(
+      exception.code,
+      exception.message,
+      exception.details
+    )
+  } else {
+    return listOf(
+      exception.javaClass.simpleName,
+      exception.toString(),
+      "Cause: " + exception.cause + ", Stacktrace: " + Log.getStackTraceString(exception)
+    )
+  }
+}
+
+/**
+ * Error class for passing custom error details to Flutter via a thrown PlatformException.
+ * @property code The error code.
+ * @property message The error message.
+ * @property details The error details. Must be a datatype supported by the api codec.
+ */
+class FlutterError (
+  val code: String,
+  override val message: String? = null,
+  val details: Any? = null
+) : Throwable()
+
+enum class HashAlgorithm(val raw: Int) {
+  SHA256(0),
+  SHA384(1),
+  SHA512(2);
+
+  companion object {
+    fun ofRaw(raw: Int): HashAlgorithm? {
+      return values().firstOrNull { it.raw == raw }
+    }
+  }
+}
+
+enum class CipherAlgorithm(val raw: Int) {
+  AES(0);
+
+  companion object {
+    fun ofRaw(raw: Int): CipherAlgorithm? {
+      return values().firstOrNull { it.raw == raw }
+    }
+  }
+}
+/** Generated interface from Pigeon that represents a handler of messages from Flutter. */
+interface NativeCryptoAPI {
+  fun hash(data: ByteArray, algorithm: HashAlgorithm): ByteArray?
+  fun hmac(data: ByteArray, key: ByteArray, algorithm: HashAlgorithm): ByteArray?
+  fun generateSecureRandom(length: Long): ByteArray?
+  fun pbkdf2(password: ByteArray, salt: ByteArray, length: Long, iterations: Long, algorithm: HashAlgorithm): ByteArray?
+  fun encrypt(plainText: ByteArray, key: ByteArray, algorithm: CipherAlgorithm): ByteArray?
+  fun encryptWithIV(plainText: ByteArray, iv: ByteArray, key: ByteArray, algorithm: CipherAlgorithm): ByteArray?
+  fun decrypt(cipherText: ByteArray, key: ByteArray, algorithm: CipherAlgorithm): ByteArray?
+  fun encryptFile(plainTextPath: String, cipherTextPath: String, key: ByteArray, algorithm: CipherAlgorithm): Boolean?
+  fun encryptFileWithIV(plainTextPath: String, cipherTextPath: String, iv: ByteArray, key: ByteArray, algorithm: CipherAlgorithm): Boolean?
+  fun decryptFile(cipherTextPath: String, plainTextPath: String, key: ByteArray, algorithm: CipherAlgorithm): Boolean?
+
+  companion object {
+    /** The codec used by NativeCryptoAPI. */
+    val codec: MessageCodec<Any?> by lazy {
+      StandardMessageCodec()
+    }
+    /** Sets up an instance of `NativeCryptoAPI` to handle messages through the `binaryMessenger`. */
+    @Suppress("UNCHECKED_CAST")
+    fun setUp(binaryMessenger: BinaryMessenger, api: NativeCryptoAPI?) {
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.hash", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val dataArg = args[0] as ByteArray
+            val algorithmArg = HashAlgorithm.ofRaw(args[1] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.hash(dataArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.hmac", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val dataArg = args[0] as ByteArray
+            val keyArg = args[1] as ByteArray
+            val algorithmArg = HashAlgorithm.ofRaw(args[2] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.hmac(dataArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.generateSecureRandom", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val lengthArg = args[0].let { if (it is Int) it.toLong() else it as Long }
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.generateSecureRandom(lengthArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.pbkdf2", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val passwordArg = args[0] as ByteArray
+            val saltArg = args[1] as ByteArray
+            val lengthArg = args[2].let { if (it is Int) it.toLong() else it as Long }
+            val iterationsArg = args[3].let { if (it is Int) it.toLong() else it as Long }
+            val algorithmArg = HashAlgorithm.ofRaw(args[4] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.pbkdf2(passwordArg, saltArg, lengthArg, iterationsArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.encrypt", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val plainTextArg = args[0] as ByteArray
+            val keyArg = args[1] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[2] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.encrypt(plainTextArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.encryptWithIV", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val plainTextArg = args[0] as ByteArray
+            val ivArg = args[1] as ByteArray
+            val keyArg = args[2] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[3] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.encryptWithIV(plainTextArg, ivArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.decrypt", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val cipherTextArg = args[0] as ByteArray
+            val keyArg = args[1] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[2] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.decrypt(cipherTextArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.encryptFile", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val plainTextPathArg = args[0] as String
+            val cipherTextPathArg = args[1] as String
+            val keyArg = args[2] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[3] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.encryptFile(plainTextPathArg, cipherTextPathArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.encryptFileWithIV", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val plainTextPathArg = args[0] as String
+            val cipherTextPathArg = args[1] as String
+            val ivArg = args[2] as ByteArray
+            val keyArg = args[3] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[4] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.encryptFileWithIV(plainTextPathArg, cipherTextPathArg, ivArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.NativeCryptoAPI.decryptFile", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val cipherTextPathArg = args[0] as String
+            val plainTextPathArg = args[1] as String
+            val keyArg = args[2] as ByteArray
+            val algorithmArg = CipherAlgorithm.ofRaw(args[3] as Int)!!
+            var wrapped: List<Any?>
+            try {
+              wrapped = listOf<Any?>(api.decryptFile(cipherTextPathArg, plainTextPathArg, keyArg, algorithmArg))
+            } catch (exception: Throwable) {
+              wrapped = wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+    }
+  }
+}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/ciphers/AES.kt

@@ -1,55 +1,146 @@
 package fr.pointcheval.native_crypto_android.ciphers
 
 import fr.pointcheval.native_crypto_android.interfaces.Cipher
-import fr.pointcheval.native_crypto_android.utils.CipherAlgorithm
-import javax.crypto.SecretKey
+import fr.pointcheval.native_crypto_android.utils.FileParameters
+import javax.crypto.CipherOutputStream
 import javax.crypto.spec.GCMParameterSpec
-import javax.crypto.spec.IvParameterSpec
 import javax.crypto.spec.SecretKeySpec
 
 class AES : Cipher {
-    override val algorithm: CipherAlgorithm
-        get() = CipherAlgorithm.aes
+   private var cipherInstance: javax.crypto.Cipher? = null
 
-    var cipherInstance: javax.crypto.Cipher? = null;
-
-    fun lazyLoadCipher() {
+    private fun lazyLoadCipher() {
         if (cipherInstance == null) {
             cipherInstance = javax.crypto.Cipher.getInstance("AES/GCM/NoPadding")
         }
     }
 
+
     // native.crypto cipherText representation = [NONCE(12) || CIPHERTEXT(n-28) || TAG(16)]
-    // javax.crypto cipherText representation = [NONCE(12)] + [CIPHERTEXT(n-16) || TAG(16)]
-    override fun encrypt(data: ByteArray, key: ByteArray): ByteArray {
-        val list : List<ByteArray> = encryptAsList(data, key)
-        return list.first().plus(list.last())
+    override fun encrypt(data: ByteArray, key: ByteArray, predefinedIV: ByteArray?): ByteArray {
+        // Initialize secret key spec
+        val sk = SecretKeySpec(key, "AES")
+
+        // Initialize cipher (if not already done)
+        lazyLoadCipher()
+
+        // If predefinedIV is not null, use it
+        if (predefinedIV != null && predefinedIV.isNotEmpty()) {
+            // Here we use the predefinedIV as the nonce (12 bytes)
+            // And we set the tag length to 16 bytes (128 bits)
+            val gcmParameterSpec = GCMParameterSpec(16*8, predefinedIV)
+            cipherInstance!!.init(javax.crypto.Cipher.ENCRYPT_MODE, sk, gcmParameterSpec)
+        } else {
+            // If predefinedIV is null, we generate a new one
+            cipherInstance!!.init(javax.crypto.Cipher.ENCRYPT_MODE, sk)
         }
 
-    // native.crypto cipherText representation = [NONCE(12)] + [CIPHERTEXT(n-16) || TAG(16)]
-    // javax.crypto cipherText representation = [NONCE(12)] + [CIPHERTEXT(n-16) || TAG(16)]
-    override fun encryptAsList(data: ByteArray, key: ByteArray): List<ByteArray> {
-        val sk = SecretKeySpec(key, "AES")
-        lazyLoadCipher()
-        cipherInstance!!.init(javax.crypto.Cipher.ENCRYPT_MODE, sk)
+        // Encrypt data
         val bytes: ByteArray = cipherInstance!!.doFinal(data)
         val iv: ByteArray = cipherInstance!!.iv
-        return listOf(iv, bytes)
+
+        return iv.plus(bytes)
+    }
+
+    override fun encryptFile(fileParameters: FileParameters, key: ByteArray, predefinedIV: ByteArray?): Boolean {
+        // Initialize secret key spec
+        val sk = SecretKeySpec(key, "AES")
+
+        // Initialize cipher (if not already done)
+        lazyLoadCipher()
+
+        // If predefinedIV is not null, use it
+        if (predefinedIV != null && predefinedIV.isNotEmpty()) {
+            // Here we use the predefinedIV as the nonce (12 bytes)
+            // And we set the tag length to 16 bytes (128 bits)
+            val gcmParameterSpec = GCMParameterSpec(16*8, predefinedIV)
+            cipherInstance!!.init(javax.crypto.Cipher.ENCRYPT_MODE, sk, gcmParameterSpec)
+        } else {
+            // If predefinedIV is null, we generate a new one
+            cipherInstance!!.init(javax.crypto.Cipher.ENCRYPT_MODE, sk)
+        }
+
+        var len: Int?
+        val buffer = ByteArray(8192)
+        val inputFile = fileParameters.getFileInputStream()
+        val outputFile = fileParameters.getFileOutputStream()
+        val iv: ByteArray? = cipherInstance!!.iv
+
+        outputFile?.write(iv)
+        outputFile?.flush()
+
+        val encryptedStream = CipherOutputStream(outputFile!!, cipherInstance)
+        while(true) {
+            len = inputFile?.read(buffer)
+            if (len != null && len > 0) {
+                encryptedStream.write(buffer,0,len)
+            } else {
+                break
+            }
+        }
+        encryptedStream.flush()
+        encryptedStream.close()
+        inputFile?.close()
+        outputFile.close()
+
+        return fileParameters.outputExists()
     }
 
     override fun decrypt(data: ByteArray, key: ByteArray): ByteArray {
+        // Extract the IV from the cipherText
         val iv: ByteArray = data.take(12).toByteArray()
         val payload: ByteArray = data.drop(12).toByteArray()
-        return decryptAsList(listOf(iv, payload), key)
-    }
 
-    override fun decryptAsList(data: List<ByteArray>, key: ByteArray): ByteArray {
+        // Initialize secret key spec
         val sk = SecretKeySpec(key, "AES")
-        val payload: ByteArray = data.last()
-        val iv: ByteArray = data.first()
-        val gcmSpec = GCMParameterSpec(16 * 8, iv)
+
+        // Initialize GCMParameterSpec
+        val gcmParameterSpec = GCMParameterSpec(16 * 8, iv)
+
+        // Initialize cipher (if not already done)
         lazyLoadCipher()
-        cipherInstance!!.init(javax.crypto.Cipher.DECRYPT_MODE, sk, gcmSpec)
+        cipherInstance!!.init(javax.crypto.Cipher.DECRYPT_MODE, sk, gcmParameterSpec)
+
+        // Decrypt data
         return cipherInstance!!.doFinal(payload)
     }
+
+    override fun decryptFile(fileParameters: FileParameters, key: ByteArray): Boolean {
+        val iv = ByteArray(12)
+        val inputFile = fileParameters.getFileInputStream() ?: throw Exception("Error while reading IV")
+
+        // Read the first 12 bytes from the file
+        for (i in 0 until 12) {
+            iv[i] = inputFile.read().toByte()
+        }
+
+        // Initialize secret key spec
+        val sk = SecretKeySpec(key, "AES")
+
+        // Initialize GCMParameterSpec
+        val gcmParameterSpec = GCMParameterSpec(16 * 8, iv)
+
+        // Initialize cipher (if not already done)
+        lazyLoadCipher()
+
+        cipherInstance!!.init(javax.crypto.Cipher.DECRYPT_MODE, sk, gcmParameterSpec)
+
+        var len: Int?
+        val buffer = ByteArray(8192)
+        val outputFile = fileParameters.getFileOutputStream()
+        val decryptedStream = CipherOutputStream(outputFile!!, cipherInstance)
+        while (true) {
+            len = inputFile.read(buffer)
+            if(len > 0){
+                decryptedStream.write(buffer,0, len)
+            } else {
+                break
+            }
+        }
+        decryptedStream.flush()
+        decryptedStream.close()
+        inputFile.close()
+
+        return fileParameters.outputExists()
+    }
 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/interfaces/Cipher.kt

@@ -1,12 +1,10 @@
 package fr.pointcheval.native_crypto_android.interfaces
 
-import fr.pointcheval.native_crypto_android.utils.CipherAlgorithm
+import fr.pointcheval.native_crypto_android.utils.FileParameters
 
 interface Cipher {
-    val algorithm: CipherAlgorithm
-
-    fun encrypt(data: ByteArray, key: ByteArray): ByteArray
+    fun encrypt(data: ByteArray, key: ByteArray, predefinedIV: ByteArray?): ByteArray
     fun decrypt(data: ByteArray, key: ByteArray): ByteArray
-    fun encryptAsList(data: ByteArray, key: ByteArray): List<ByteArray>
-    fun decryptAsList(data: List<ByteArray>, key: ByteArray): ByteArray
+    fun encryptFile(fileParameters: FileParameters, key: ByteArray, predefinedIV: ByteArray?): Boolean
+    fun decryptFile(fileParameters: FileParameters, key: ByteArray): Boolean
 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/interfaces/Key.kt

@@ -1,5 +0,0 @@
-package fr.pointcheval.native_crypto_android.interfaces
-
-interface Key {
-    val bytes: ByteArray
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/interfaces/KeyDerivation.kt

@@ -1,10 +1,5 @@
 package fr.pointcheval.native_crypto_android.interfaces
 
-import fr.pointcheval.native_crypto_android.keys.SecretKey
-import fr.pointcheval.native_crypto_android.utils.KdfAlgorithm
-
 interface KeyDerivation {
-    val algorithm: KdfAlgorithm
-
-    fun derive(): SecretKey
+    fun derive(): ByteArray?
 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/kdf/Pbkdf2.kt

@@ -1,39 +1,43 @@
 package fr.pointcheval.native_crypto_android.kdf
 
+import fr.pointcheval.native_crypto_android.HashAlgorithm
 import fr.pointcheval.native_crypto_android.interfaces.KeyDerivation
-import fr.pointcheval.native_crypto_android.keys.SecretKey
-import fr.pointcheval.native_crypto_android.utils.HashAlgorithm
-import fr.pointcheval.native_crypto_android.utils.KdfAlgorithm
+import fr.pointcheval.native_crypto_android.utils.HashAlgorithmParser
 import javax.crypto.SecretKeyFactory
 import javax.crypto.spec.PBEKeySpec
 
 class Pbkdf2(
-    private val keyBytesCount: Int, private val iterations: Int,
-    private val hash: HashAlgorithm = HashAlgorithm.sha256
+    private val length: Int, private val iterations: Int,
+    private val hashAlgorithm: HashAlgorithm
 ) : KeyDerivation {
 
-    private var password: String? = null
-    private var salt: String? = null
+    private var password: CharArray? = null
+    private var salt: ByteArray? = null
 
-    fun init(password: String, salt: String) {
-        this.password = password
+    fun init(password: ByteArray, salt: ByteArray) {
+        // Transform the password to a char array
+        val passwordCharArray = CharArray(password.size)
+        for (i in password.indices) {
+            passwordCharArray[i] = password[i].toInt().toChar()
+        }
+
+        this.password = passwordCharArray
         this.salt = salt
     }
 
-    override val algorithm: KdfAlgorithm
-        get() = KdfAlgorithm.pbkdf2
-
-    override fun derive(): SecretKey {
+    override fun derive(): ByteArray? {
         if (password == null || salt == null) {
             throw Exception("Password and Salt must be initialized.")
         }
         val spec = PBEKeySpec(
-            password!!.toCharArray(),
-            salt!!.toByteArray(),
+            password!!,
+            salt!!,
             iterations,
-            keyBytesCount * 8
+            length * 8
         )
-        val skf: SecretKeyFactory = SecretKeyFactory.getInstance(hash.pbkdf2String())
-        return SecretKey(skf.generateSecret(spec).encoded)
+        val skf: SecretKeyFactory =
+            SecretKeyFactory.getInstance(HashAlgorithmParser.getPbkdf2String(hashAlgorithm))
+
+        return skf.generateSecret(spec).encoded
     }
 }

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/keys/SecretKey.kt

@@ -1,14 +0,0 @@
-package fr.pointcheval.native_crypto_android.keys
-
-import fr.pointcheval.native_crypto_android.interfaces.Key
-import java.security.SecureRandom
-
-class SecretKey(override val bytes: ByteArray) : Key {
-    companion object {
-        fun fromSecureRandom(bitsCount: Int): SecretKey {
-            val bytes = ByteArray(bitsCount / 8)
-            SecureRandom.getInstanceStrong().nextBytes(bytes)
-            return SecretKey(bytes)
-        }
-    }
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/CipherAlgorithm.kt

@@ -1,14 +0,0 @@
-package fr.pointcheval.native_crypto_android.utils
-
-import fr.pointcheval.native_crypto_android.ciphers.AES
-import fr.pointcheval.native_crypto_android.interfaces.Cipher
-
-enum class CipherAlgorithm {
-    aes;
-
-    fun getCipher(): Cipher {
-        return when (this) {
-            aes -> AES()
-        }
-    }
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/Constants.kt

@@ -1,14 +0,0 @@
-package fr.pointcheval.native_crypto_android.utils
-
-object Constants {
-    const val ALGORITHM = "algorithm"
-    const val BITS_COUNT = "bitsCount"
-    const val DATA = "data"
-    const val PASSWORD = "password"
-    const val SALT = "salt"
-    const val KEY = "key"
-    const val KEY_BYTES_COUNT = "keyBytesCount"
-    const val ITERATIONS = "iterations"
-    const val EPHEMERAL_PRIVATE_KEY = "ephemeralPrivateKey"
-    const val OTHER_PUBLIC_KEY = "otherPublicKey"
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/FileParameters.kt

@@ -0,0 +1,71 @@
+package fr.pointcheval.native_crypto_android.utils
+
+import android.content.Context
+import android.content.res.Resources
+import android.net.Uri
+import androidx.documentfile.provider.DocumentFile
+import java.io.*
+
+class FileParameters(ctx: Context, input: String, output: String) {
+    private var context: Context
+
+    private var inputPath: String
+    private var outputPath: String
+
+    init {
+        this.context = ctx
+        this.inputPath = input
+        this.outputPath = output
+    }
+
+    private fun getUri(): Uri? {
+        val persistedUriPermissions = context.contentResolver.persistedUriPermissions
+        if (persistedUriPermissions.size > 0) {
+            val uriPermission = persistedUriPermissions[0]
+            return uriPermission.uri
+        }
+        return null
+    }
+
+    private fun getDocumentFileByPath(path: String): DocumentFile {
+        var doc = DocumentFile.fromTreeUri(context, getUri()!!)
+        val parts = path.split("/")
+        for (i in parts.indices) {
+            val nextFile = doc?.findFile(parts[i])
+            if(nextFile != null){
+                doc = nextFile
+            }
+        }
+        if (doc != null){
+            return doc
+        } else {
+            throw Resources.NotFoundException("File not found")
+        }
+    }
+
+    fun getFileOutputStream(): OutputStream? {
+        val path = outputPath
+        return try{
+            FileOutputStream(path)
+        } catch(e: IOException){
+            val documentFile: DocumentFile = this.getDocumentFileByPath(path)
+            val documentUri = documentFile.uri
+            context.contentResolver.openOutputStream(documentUri)
+        }
+    }
+
+    fun getFileInputStream(): InputStream? {
+        val path = inputPath
+        return try{
+            FileInputStream(path)
+        } catch(e: IOException){
+            val documentFile: DocumentFile = this.getDocumentFileByPath(path)
+            val documentUri = documentFile.uri
+            context.contentResolver.openInputStream(documentUri)
+        }
+    }
+
+    fun outputExists(): Boolean {
+        return File(outputPath).exists()
+    }
+}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/HashAlgorithm.kt

@@ -1,50 +0,0 @@
-package fr.pointcheval.native_crypto_android.utils
-
-import java.security.MessageDigest
-
-@Suppress("EnumEntryName")
-enum class HashAlgorithm(val bitsCount: Int) {
-    sha256(256),
-    sha384(384),
-    sha512(512);
-
-    fun messageDigestString(): String {
-        return when (this) {
-            sha256 -> "SHA-256"
-            sha384 -> "SHA-384"
-            sha512 -> "SHA-512"
-        }
-    }
-
-    fun hmacString(): String {
-        return when (this) {
-            sha256 -> "HmacSHA256"
-            sha384 -> "HmacSHA384"
-            sha512 -> "HmacSHA512"
-        }
-    }
-
-    fun pbkdf2String(): String {
-        return when (this) {
-            sha256 -> "PBKDF2WithHmacSHA256"
-            sha384 -> "PBKDF2WithHmacSHA384"
-            sha512 -> "PBKDF2WithHmacSHA512"
-        }
-    }
-
-    fun digest(data: ByteArray): ByteArray {
-        val md = MessageDigest.getInstance(messageDigestString())
-        return md.digest(data)
-    }
-
-    companion object {
-        fun digest(data: ByteArray, algorithm: String): ByteArray {
-            for (h in values()) {
-                if (h.name == algorithm) {
-                    return h.digest(data)
-                }
-            }
-            throw Exception("Unknown HashAlgorithm: $algorithm")
-        }
-    }
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/HashAlgorithmParser.kt

@@ -0,0 +1,31 @@
+package fr.pointcheval.native_crypto_android.utils
+
+import fr.pointcheval.native_crypto_android.HashAlgorithm
+import java.security.MessageDigest
+import javax.crypto.Mac
+
+object HashAlgorithmParser {
+    fun getMessageDigest(algorithm: HashAlgorithm): MessageDigest {
+        return when (algorithm) {
+            HashAlgorithm.SHA256 -> MessageDigest.getInstance("SHA-256")
+            HashAlgorithm.SHA384 -> MessageDigest.getInstance("SHA-384")
+            HashAlgorithm.SHA512 -> MessageDigest.getInstance("SHA-512")
+        }
+    }
+
+    fun getMac(algorithm: HashAlgorithm): Mac {
+        return when (algorithm) {
+            HashAlgorithm.SHA256 -> Mac.getInstance("HmacSHA256")
+            HashAlgorithm.SHA384 -> Mac.getInstance("HmacSHA384")
+            HashAlgorithm.SHA512 -> Mac.getInstance("HmacSHA512")
+        }
+    }
+
+    fun getPbkdf2String(algorithm: HashAlgorithm): String {
+        return when (algorithm) {
+            HashAlgorithm.SHA256 -> "PBKDF2WithHmacSHA256"
+            HashAlgorithm.SHA384 -> "PBKDF2WithHmacSHA384"
+            HashAlgorithm.SHA512 -> "PBKDF2WithHmacSHA512"
+        }
+    }
+}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/KdfAlgorithm.kt

@@ -1,5 +0,0 @@
-package fr.pointcheval.native_crypto_android.utils
-
-enum class KdfAlgorithm {
-    pbkdf2
-}

packages/native_crypto_android/android/src/main/kotlin/fr/pointcheval/native_crypto_android/utils/Task.kt

@@ -1,44 +0,0 @@
-package fr.pointcheval.native_crypto_android.utils
-
-class Task<T>(private var task: () -> T) {
-
-    private var successful = false
-    private var result: T? = null
-    private var exception: Exception? = null
-
-    fun isSuccessful(): Boolean {
-        return successful
-    }
-
-    fun getResult(): T {
-        if (successful && result != null) {
-            return result!!
-        } else {
-            throw Exception("No result found!")
-        }
-    }
-
-    fun getException(): Exception {
-        if (exception != null) {
-            return exception!!
-        } else {
-            throw Exception("No exception found!")
-        }
-    }
-
-    fun call() {
-        try {
-            result = task()
-            exception = null
-            successful = true
-        } catch (e: Exception) {
-            exception = e
-            result = null
-            successful = false
-        }
-    }
-
-    fun finalize(callback: (task: Task<T>) -> Unit) {
-        callback(this)
-    }
-}