2023-04-03 11:04:31 +08:00

109 lines
3.0 KiB
C#

using System;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Text;
using System.Security.Cryptography;
namespace BF
{
/// <summary>
/// rc4流式加密解密
/// 加密是连续的,加密完成之后再解密
/// 速度快,可以用在协议或日志
/// </summary>
public class Rc4Encrypt
{
private byte[] keyStream;
public string Key
{
set
{
keyStream = Encoding.UTF8.GetBytes(value);
}
}
private byte[] Encrypt(byte[] pwd, byte[] data)
{
if (ReferenceEquals(pwd, null))
{
return data;
}
if (pwd.Length <= 0 || data.Length <= 0)
{
return data;
}
int a, i, j, k, tmp;
int[] key, box;
byte[] cipher;
key = new int[256];
box = new int[256];
cipher = new byte[data.Length];
for (i = 0; i < 256; i++) {
key[i] = pwd[i % pwd.Length];
box[i] = i;
}
for (j = i = 0; i < 256; i++) {
j = (j + box[i] + key[i]) % 256;
tmp = box[i];
box[i] = box[j];
box[j] = tmp;
}
for (a = j = i = 0; i < data.Length; i++) {
a++;
a %= 256;
j += box[a];
j %= 256;
tmp = box[a];
box[a] = box[j];
box[j] = tmp;
k = box[((box[a] + box[j]) % 256)];
cipher[i] = (byte)(data[i] ^ k);
}
return cipher;
}
private byte[] Decrypt(byte[] pwd, byte[] data) {
return Encrypt(pwd, data);
}
// public static string EncryptBytes(byte[] data, bool toBase64 = false)
// {
// byte[] encryptData = Encrypt(keyStream, data);
//
// var r = toBase64
// ? Convert.ToBase64String(encryptData)
// : Encoding.UTF8.GetString(Encoding.UTF8.GetBytes(Convert.ToBase64String(encryptData)));
//
// return r;
// }
// public static string DecryptBytes(byte[] data)
// {
// return Encoding.UTF8.GetString(Decrypt(keyStream, data));
// }
public byte[] EncryptBytes(byte[] bytes)
{
return Encrypt(keyStream, bytes);
}
public byte[]DecryptBytes(byte[] bytes)
{
return Decrypt(keyStream, bytes);
}
public byte[] EncryptStr(string data)
{
byte[] bytes = Encoding.UTF8.GetBytes(data);
return Encrypt(keyStream, bytes);
}
public byte[] DecryptStr(string data)
{
byte[] bytes = Encoding.UTF8.GetBytes(data); //Convert.FromBase64String(Encoding.UTF8.GetString(Encoding.UTF8.GetBytes(data)));
return Decrypt(keyStream, bytes);
}
}
}