diff --git a/domain/build.gradle.kts b/domain/build.gradle.kts
index 1474413..69a0129 100644
--- a/domain/build.gradle.kts
+++ b/domain/build.gradle.kts
@@ -11,4 +11,5 @@ java {
 
 dependencies {
     implementation(libs.kotlinx.coroutines.core)
+    testImplementation(libs.junit)
 }
\ No newline at end of file
diff --git a/domain/src/main/java/com/github/nullptroma/wallenc/domain/datatypes/EncryptKey.kt b/domain/src/main/java/com/github/nullptroma/wallenc/domain/datatypes/EncryptKey.kt
index 286f442..ca565c3 100644
--- a/domain/src/main/java/com/github/nullptroma/wallenc/domain/datatypes/EncryptKey.kt
+++ b/domain/src/main/java/com/github/nullptroma/wallenc/domain/datatypes/EncryptKey.kt
@@ -1,10 +1,15 @@
 package com.github.nullptroma.wallenc.domain.datatypes
 
 import java.security.MessageDigest
+import javax.crypto.spec.SecretKeySpec
 
 class EncryptKey(val key: String) {
     fun to32Bytes(): ByteArray {
         val digest = MessageDigest.getInstance("SHA-256")
         return digest.digest(key.toByteArray(Charsets.UTF_8))
     }
+
+    fun toAesKey() : SecretKeySpec {
+        return SecretKeySpec(to32Bytes(), "AES")
+    }
 }
\ No newline at end of file
diff --git a/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/EncryptedStorageAccessor.kt b/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/EncryptedStorageAccessor.kt
index 37e6213..0206172 100644
--- a/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/EncryptedStorageAccessor.kt
+++ b/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/EncryptedStorageAccessor.kt
@@ -5,7 +5,6 @@ import com.github.nullptroma.wallenc.domain.common.impl.CommonFile
 import com.github.nullptroma.wallenc.domain.common.impl.CommonMetaInfo
 import com.github.nullptroma.wallenc.domain.datatypes.DataPackage
 import com.github.nullptroma.wallenc.domain.datatypes.EncryptKey
-import com.github.nullptroma.wallenc.domain.datatypes.StorageEncryptionInfo
 import com.github.nullptroma.wallenc.domain.interfaces.IDirectory
 import com.github.nullptroma.wallenc.domain.interfaces.IFile
 import com.github.nullptroma.wallenc.domain.interfaces.ILogger
@@ -23,7 +22,6 @@ import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
 import java.io.InputStream
 import java.io.OutputStream
-import javax.crypto.spec.SecretKeySpec
 import kotlin.io.path.Path
 import kotlin.io.path.pathString
 
@@ -46,7 +44,7 @@ class EncryptedStorageAccessor(
     private val _dirsUpdates = MutableSharedFlow<DataPackage<List<IDirectory>>>()
     override val dirsUpdates: SharedFlow<DataPackage<List<IDirectory>>> = _dirsUpdates
 
-    private val _encryptor = Encryptor(SecretKeySpec(key.to32Bytes(), "AES"))
+    private val _encryptor = Encryptor(key.toAesKey())
 
     init {
         collectSourceState()
@@ -217,14 +215,4 @@ class EncryptedStorageAccessor(
         _job.cancel()
         _encryptor.dispose()
     }
-
-
-    companion object {
-        private const val IV_LEN = 16
-        private const val AES_SETTINGS = "AES/CBC/PKCS5Padding"
-
-        fun generateEncryptionInfo(key: EncryptKey): StorageEncryptionInfo {
-            TODO()
-        }
-    }
 }
\ No newline at end of file
diff --git a/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/Encryptor.kt b/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/Encryptor.kt
index c6e54a2..76ea838 100644
--- a/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/Encryptor.kt
+++ b/domain/src/main/java/com/github/nullptroma/wallenc/domain/encrypt/Encryptor.kt
@@ -1,5 +1,7 @@
 package com.github.nullptroma.wallenc.domain.encrypt
 
+import com.github.nullptroma.wallenc.domain.datatypes.EncryptKey
+import com.github.nullptroma.wallenc.domain.datatypes.StorageEncryptionInfo
 import kotlinx.coroutines.DisposableHandle
 import java.io.InputStream
 import java.io.OutputStream
@@ -74,8 +76,33 @@ class Encryptor(private var _secretKey: SecretKey?) : DisposableHandle {
 
     companion object {
         private const val IV_LEN = 16
+        private const val TEST_DATA_LEN = 512
         private const val AES_SETTINGS = "AES/CBC/PKCS5Padding"
 
-        
+        @OptIn(ExperimentalEncodingApi::class)
+        fun generateEncryptionInfo(key: EncryptKey) : StorageEncryptionInfo {
+            val encryptor = Encryptor(key.toAesKey())
+            val testData = ByteArray(TEST_DATA_LEN)
+            val encryptedData = encryptor.encryptBytes(testData)
+            return StorageEncryptionInfo(
+                isEncrypted = true,
+                encryptedTestData = Base64.Default.encode(encryptedData)
+            )
+        }
+
+        @OptIn(ExperimentalEncodingApi::class)
+        fun checkKey(key: EncryptKey, encInfo: StorageEncryptionInfo): Boolean {
+            if(encInfo.encryptedTestData == null)
+                return false
+            val encryptor = Encryptor(key.toAesKey())
+            try {
+                val encData = Base64.Default.decode(encInfo.encryptedTestData)
+                val testData = encryptor.decryptBytes(encData)
+                return testData.all { it == 0.toByte() } && testData.size == TEST_DATA_LEN
+            }
+            catch (e: Exception) {
+                return false
+            }
+        }
     }
 }
\ No newline at end of file