Basic implementation of AES encryption/decryption and respective OSSL functions

Add methods:
+ private static string AESEncryptString(string secret, string plainText, string ivString= null)
AES Encrypt a string using a password and a random or custom Initialization Vector.

+ private static string AESDecryptString(string secret, string encryptedText, string ivString= null)
AES Decrypt the string encrypted by AESEncryptString with the same password and ivString used in the encryption.

Methods implementations:
+ Util.AESEncrypt(string secret, string plainText)
+ Util.AESDecrypt(string secret, string encryptedText)
+Util.AESEncryptTo(string secret, string plainText, string ivString)
+ Util.AESDecryptFrom(string secret, string encryptedText, string ivString)

OSSL functions as first case of use:
+ osAESEncrypt(string secret, string plainText)
+ osAESDecrypt(string secret, string encryptedText)
+ osAESEncryptTo(string secret, string plainText, string ivString)
+ osAESDecryptFrom(string secret, string encryptedText, string ivString)

LSL script example:
<pre><code>
string plainText = "Hello World :)";
string secret = "#!qUeRtY$@123^456€!#";

default
{
    touch_start(integer i)
    {
        string encryptedText = osAESEncrypt(secret, plainText);
        llOwnerSay("\nEncrypted with osAESEncrypt:\n"+ encryptedText);
        string decryptedText = osAESDecrypt(secret, encryptedText);
        llOwnerSay("\nDecrypted with osAESDecrypt:\n"+ decryptedText);

        // Encription / Decription with custom Initialization Vector.
        string ivString = (string)llGetOwner() /* +"_"+ llGenerateKey() */;
        string encryptedToText = osAESEncryptTo(secret, plainText, ivString);
        llOwnerSay("\nEncrypted with osAESEncryptTo:\n"+ encryptedToText);
        string decryptedFromText = osAESDecryptFrom(secret, encryptedToText, ivString);
        llOwnerSay("\nDecrypted with osAESDecryptFrom:\n"+ decryptedFromText);
    }
}
</code></pre>

Web Rain :)

OpenSim/Region/ScriptEngine/Shared/Api/Implementation/OSSL_Api.cs

@@ -6374,5 +6374,65 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
 
             return World.TryGetSceneObjectPart(id, out SceneObjectPart part) ? part.ParentGroup.GetSittingAvatarsCount() : 0;
         }
+
+        public LSL_String osAESEncrypt(string secret, string plainText)
+        {
+            if(string.IsNullOrEmpty(secret) || string.IsNullOrEmpty(plainText))
+                return LSL_String.Empty;
+
+            LSL_String ret = Util.AESEncrypt(secret, plainText);
+            if(string.IsNullOrEmpty(ret)){
+                OSSLError("osAESEncrypt: Failed to encrypt!");
+                return LSL_String.Empty;
+            }else
+            {
+                return ret;
+            }
+        }
+
+        public LSL_String osAESDecrypt(string secret, string encryptedText)
+        {
+            if(string.IsNullOrEmpty(secret) || string.IsNullOrEmpty(encryptedText))
+                return LSL_String.Empty;
+
+            LSL_String ret = Util.AESDecrypt(secret, encryptedText);
+            if(string.IsNullOrEmpty(ret)){
+                OSSLError("osAESDecrypt: Failed to Decrypt!");
+                return LSL_String.Empty;
+            }else
+            {
+                return ret;
+            }
+        }
+
+        public LSL_String osAESEncryptTo(string secret, string plainText, string ivString)
+        {
+            if(string.IsNullOrEmpty(secret) || string.IsNullOrEmpty(plainText) || string.IsNullOrEmpty(ivString))
+                return LSL_String.Empty;
+
+            LSL_String ret = Util.AESEncryptTo(secret, plainText, ivString);
+            if(string.IsNullOrEmpty(ret)){
+                OSSLError("osAESEncryptTo: Failed to encrypt!");
+                return LSL_String.Empty;
+            }else
+            {
+                return ret;
+            }
+        }
+
+        public LSL_String osAESDecryptFrom(string secret, string encryptedText, string ivString)
+        {
+            if(string.IsNullOrEmpty(secret) || string.IsNullOrEmpty(encryptedText) || string.IsNullOrEmpty(ivString))
+                return LSL_String.Empty;
+
+            LSL_String ret = Util.AESDecryptFrom(secret, encryptedText, ivString);
+            if(string.IsNullOrEmpty(ret)){
+                OSSLError("osAESDecryptFrom: Failed to decrypt!");
+                return LSL_String.Empty;
+            }else
+            {
+                return ret;
+            }
+        }
     }
 }