CypherRSA.cs

using System.Diagnostics;
using System.Security.Cryptography;
using System.Text;

namespace CypherRSA;

// Max Lengh Support 379 Characters
public static class CypherRSA
{
    public static void GenerateKeys(out byte[] publicKey, out byte[] privateKey)
    {
        try
        {
            using RSA rsaKey = RSA.Create(4096);
            publicKey = rsaKey.ExportRSAPublicKey();
            privateKey = rsaKey.ExportRSAPrivateKey();
            rsaKey.Clear();
        }
        catch (Exception ex)
        {
            publicKey = Array.Empty<byte>();
            privateKey = Array.Empty<byte>();
            Debug.WriteLine("CypherTool GenerateKeys: " + ex.Message);
        }
    }

    public static bool TryEncrypt(byte[] input, byte[] publicKey, out byte[] encryptedBytes, out string encryptedHex)
    {
        try
        {
            using RSA rsaKey = RSA.Create(4096);
            rsaKey.ImportRSAPublicKey(publicKey, out _);
            encryptedBytes = rsaKey.Encrypt(input, RSAEncryptionPadding.OaepSHA512);
            encryptedHex = Convert.ToHexString(encryptedBytes);

            rsaKey.Clear();
            return true;
        }
        catch (Exception ex)
        {
            encryptedBytes = Array.Empty<byte>();
            encryptedHex = string.Empty;
            Debug.WriteLine("CypherTool TryEncrypt 1: " + ex.Message);
            return false;
        }
    }

    public static bool TryEncrypt(string inputText, byte[] publicKey, out byte[] encryptedBytes, out string encryptedHex)
    {
        try
        {
            byte[] inputBytes = Encoding.UTF8.GetBytes(inputText);
            return TryEncrypt(inputBytes, publicKey, out encryptedBytes, out encryptedHex);
        }
        catch (Exception ex)
        {
            encryptedBytes = Array.Empty<byte>();
            encryptedHex = string.Empty;
            Debug.WriteLine("CypherTool TryEncrypt 2: " + ex.Message);
            return false;
        }
    }

    public static bool TryDecrypt(byte[] encryptedBytes, byte[] privateKey, out byte[] decryptedBytes)
    {
        try
        {
            using RSA rsaKey = RSA.Create(4096);
            rsaKey.ImportRSAPrivateKey(privateKey, out _);
            decryptedBytes = rsaKey.Decrypt(encryptedBytes, RSAEncryptionPadding.OaepSHA512);
            rsaKey.Clear();
            return true;
        }
        catch (Exception ex)
        {
            decryptedBytes = Array.Empty<byte>();
            Debug.WriteLine("CypherTool TryDecrypt 1: " + ex.Message);
            return false;
        }
    }

    public static bool TryDecrypt(string encryptedHex, byte[] privateKey, out byte[] decryptedBytes)
    {
        try
        {
            byte[] encryptedBytes = Convert.FromHexString(encryptedHex);
            return TryDecrypt(encryptedBytes, privateKey, out decryptedBytes);
        }
        catch (Exception ex)
        {
            decryptedBytes = Array.Empty<byte>();
            Debug.WriteLine("CypherTool TryDecrypt 2: " + ex.Message);
            return false;
        }
    }

    public static bool TryDecrypt(byte[] encryptedBytes, byte[] privateKey, out string decryptedText)
    {
        bool isDecryptionSuccess = TryDecrypt(encryptedBytes, privateKey, out byte[] decryptedBytes);
        if (isDecryptionSuccess)
        {
            try
            {
                decryptedText = Encoding.UTF8.GetString(decryptedBytes);
                return true;
            }
            catch (Exception ex)
            {
                decryptedText = string.Empty;
                Debug.WriteLine("CypherTool TryDecrypt 3: " + ex.Message);
                return false;
            }
        }
        else
        {
            decryptedText = string.Empty;
            return false;
        }
    }

    public static bool TryDecrypt(string encryptedHex, byte[] privateKey, out string decryptedText)
    {
        try
        {
            byte[] encryptedBytes = Convert.FromHexString(encryptedHex);
            return TryDecrypt(encryptedBytes, privateKey, out decryptedText);
        }
        catch (Exception ex)
        {
            decryptedText = string.Empty;
            Debug.WriteLine("CypherTool TryDecrypt 4: " + ex.Message);
            return false;
        }
    }
}