updated nullability issues

src/Pandatech.Crypto/Aes256.cs

@@ -61,7 +61,8 @@ private byte[] EncryptWithHashInner(string plainText, string? key = null)
     private byte[] EncryptWithoutHashInner(string plainText, string? key)
     {
         key ??= _options.Key;
-        ValidateText(plainText);
+        if (plainText == "")
+            return [];
         using var aesAlg = Aes.Create();
         aesAlg.KeySize = KeySize;
         aesAlg.Padding = PaddingMode.PKCS7;
@@ -111,7 +112,7 @@ public string DecryptWithoutHash(byte[] cipherText, string key)
             ? ""
             : DecryptWithoutSkippingHashInner(cipherText, key);
     }
-    
+
     public void Decrypt(Stream inputStream, Stream outputStream, string? key = null)
     {
         key ??= _options.Key;
@@ -135,7 +136,8 @@ public void Decrypt(Stream inputStream, Stream outputStream, string? key = null)
     private string DecryptWithoutSkippingHashInner(byte[] cipherText, string? key)
     {
         key ??= _options.Key;
-        ValidateCipherText(cipherText);
+        if (cipherText.Length == 0)
+            return "";
         var iv = cipherText.Take(IvSize).ToArray();
         var encrypted = cipherText.Skip(IvSize).ToArray();
 
@@ -166,19 +168,6 @@ private static void ValidateKey(string key)
             throw new ArgumentException("Invalid key.");
     }
 
-    private static void ValidateText(string text)
-    {
-        if (string.IsNullOrEmpty(text) && text != null)
-            throw new ArgumentException("Text cannot be null or empty.");
-    }
-
-    private static void ValidateCipherText(byte[] cipherText)
-    {
-        if (cipherText.Length == 0) return;
-
-        if (cipherText == null || cipherText.Length < IvSize)
-            throw new ArgumentException("Invalid cipher text.");
-    }
 
     private static bool IsBase64String(string s)
     {

src/Pandatech.Crypto/Pandatech.Crypto.csproj

@@ -8,12 +8,12 @@
         <Copyright>MIT</Copyright>
         <PackageIcon>pandatech.png</PackageIcon>
         <PackageReadmeFile>Readme.md</PackageReadmeFile>
-        <Version>2.4.0</Version>
+        <Version>2.4.1</Version>
         <Title>Pandatech.Crypto</Title>
         <PackageTags>Pandatech, library, encryption, hash, algorythms, security</PackageTags>
         <Description>PandaTech.Crypto is a .NET library simplifying common cryptograhic functions.</Description>
         <RepositoryUrl>https://github.com/PandaTechAM/be-lib-pandatech-crypto</RepositoryUrl>
-        <PackageReleaseNotes>Aes256 public api has changed which causes breaking changes. Now instead of parameter of adding hash it is introduced totally new method</PackageReleaseNotes>
+        <PackageReleaseNotes>Aes256 empty string handle</PackageReleaseNotes>
     </PropertyGroup>
 
     <ItemGroup>