WingMan

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?path1? @ 11  →  ?path2? @ 12
/trunk/WingMan/Utilities/AES.cs
@@ -1,12 +1,15 @@
using System;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
 
namespace WingMan.Utilities
{
public static class AES
{
private const int AesKeyIterations = 4096;
private const int AesBlockSize = 128;
private const CipherMode AesCipherMode = CipherMode.CBC;
private const PaddingMode AesPaddingMode = PaddingMode.PKCS7;
@@ -23,7 +26,7 @@
/// <param name="key">the encryption key</param>
/// <param name="separator">the separator to use between the cyphertext and the IV</param>
/// <returns>Base64 encoded encrypted data</returns>
public static byte[] Encrypt(byte[] data, string key, string separator = ":")
public static async Task<byte[]> Encrypt(byte[] data, string key, string separator = ":")
{
using (var rijdanelManaged = new RijndaelManaged())
{
@@ -35,31 +38,24 @@
// Compute the salt and the IV from the key.
var salt = new byte[AesKeySaltBytes];
Rng.GetBytes(salt);
using (var derivedKey = new Rfc2898DeriveBytes(key, salt))
var derivedKey = new Rfc2898DeriveBytes(key, salt, AesKeyIterations);
rijdanelManaged.Key = derivedKey.GetBytes(rijdanelManaged.KeySize / 8);
rijdanelManaged.IV = derivedKey.GetBytes(rijdanelManaged.BlockSize / 8);
 
using (var encryptor = rijdanelManaged.CreateEncryptor(rijdanelManaged.Key, rijdanelManaged.IV))
{
rijdanelManaged.Key = derivedKey.GetBytes(rijdanelManaged.KeySize / 8);
rijdanelManaged.IV = derivedKey.GetBytes(rijdanelManaged.BlockSize / 8);
 
using (var encryptor = rijdanelManaged.CreateEncryptor(rijdanelManaged.Key, rijdanelManaged.IV))
using (var memoryStream = new MemoryStream())
{
using (var memoryStream = new MemoryStream())
using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
using (var inputStream = new MemoryStream(data))
{
using (var inputStream = new MemoryStream(data))
{
inputStream.CopyTo(cryptoStream);
cryptoStream.FlushFinalBlock();
await inputStream.CopyToAsync(cryptoStream);
cryptoStream.FlushFinalBlock();
 
inputStream.Position = 0L;
inputStream.Position = 0L;
 
var payload = memoryStream.ToArray();
 
var base64Salt = Convert.ToBase64String(salt);
var base64Payload = Convert.ToBase64String(payload);
 
return Encoding.UTF8.GetBytes($"{base64Salt}{separator}{base64Payload}");
}
return salt.Concat(memoryStream.ToArray()).ToArray();
}
}
}
@@ -80,15 +76,11 @@
/// <param name="key">the encryption key</param>
/// <param name="separator">the separator to use between the cyphertext and the IV</param>
/// <returns>the decrypted data</returns>
public static byte[] Decrypt(byte[] data, string key, string separator = ":")
public static async Task<byte[]> Decrypt(byte[] data, string key, string separator = ":")
{
var input = Encoding.UTF8.GetString(data);
var salt = data.Take(AesKeySaltBytes).ToArray();
var text = data.Skip(AesKeySaltBytes).ToArray();
 
// retrieve the salt from the data.
var segments = input.Split(new[] {separator}, StringSplitOptions.None);
if (segments.Length != 2)
throw new ArgumentException("Invalid data: " + input);
 
using (var rijdanelManaged = new RijndaelManaged())
{
// FIPS-197 / CBC
@@ -97,21 +89,23 @@
rijdanelManaged.Padding = AesPaddingMode;
 
// Retrieve the key and the IV from the salt.
using (var derivedKey = new Rfc2898DeriveBytes(key, Convert.FromBase64String(segments[0].Trim())))
var derivedKey = new Rfc2898DeriveBytes(key, salt, AesKeyIterations);
rijdanelManaged.Key = derivedKey.GetBytes(rijdanelManaged.KeySize / 8);
rijdanelManaged.IV = derivedKey.GetBytes(rijdanelManaged.BlockSize / 8);
 
using (var decryptor = rijdanelManaged.CreateDecryptor(rijdanelManaged.Key, rijdanelManaged.IV))
{
rijdanelManaged.Key = derivedKey.GetBytes(rijdanelManaged.KeySize / 8);
rijdanelManaged.IV = derivedKey.GetBytes(rijdanelManaged.BlockSize / 8);
 
using (var decryptor = rijdanelManaged.CreateDecryptor(rijdanelManaged.Key, rijdanelManaged.IV))
using (var memoryStream = new MemoryStream(text))
{
using (var memoryStream = new MemoryStream(Convert.FromBase64String(segments[1].Trim())))
using (var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
{
using (var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
using (var outputStream = new MemoryStream())
{
using (var streamReader = new StreamReader(cryptoStream))
{
return Encoding.UTF8.GetBytes(streamReader.ReadToEnd());
}
await cryptoStream.CopyToAsync(outputStream);
 
outputStream.Position = 0L;
 
return outputStream.ToArray();
}
}
}