duplicati/Duplicati/Library/Encryption/AESStringEncryption.cs

// Copyright (C) 2024, The Duplicati Team
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// 
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// copy of this software and associated documentation files (the "Software"), 
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// and/or sell copies of the Software, and to permit persons to whom the 
// Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in 
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
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using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

namespace Duplicati.Library.Encryption
{
    public static class AESStringEncryption
    {
        private enum Direction
        {
            Encryption,
            Decryption
        }

        public static string EncryptToHex(string passphrase, string content)
        {
            return Transform(passphrase, content, Direction.Encryption);
        }

        public static string DecryptFromHex(string passphrase, string content)
        {
            return Transform(passphrase, content, Direction.Decryption);
        }

        private static string Transform(string passphrase, string content, Direction direction)
        {
            using AESEncryption aesprovider = new AESEncryption(passphrase, new Dictionary<string, string>());
            using MemoryStream inputStream = new MemoryStream(direction == Direction.Encryption
                ? Encoding.UTF8.GetBytes(content)
                : Utility.Utility.HexStringAsByteArray(content));
            using MemoryStream outputStream = new MemoryStream();

            switch (direction)
            {
                case Direction.Encryption:
                    aesprovider.Encrypt(inputStream, outputStream);
                    return Utility.Utility.ByteArrayAsHexString(outputStream.ToArray());
                case Direction.Decryption:
                    aesprovider.Decrypt(inputStream, outputStream);
                    return Encoding.UTF8.GetString(outputStream.ToArray());
                default:
                    throw new NotImplementedException();
            }
        }
    }
}