50 lines
1.0 KiB
C#
50 lines
1.0 KiB
C#
using System;
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namespace Server.Helper;
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internal class Xor
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{
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public static byte[] DecodEncod(byte[] data, byte[] key)
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{
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int[] array = new int[256];
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for (int i = 0; i < 256; i++)
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{
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array[i] = i;
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}
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int[] array2 = new int[256];
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if (key.Length == 256)
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{
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Buffer.BlockCopy(key, 0, array2, 0, key.Length);
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}
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else
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{
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for (int j = 0; j < 256; j++)
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{
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array2[j] = key[j % key.Length];
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}
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}
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int num = 0;
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for (int k = 0; k < 256; k++)
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{
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num = (num + array[k] + array2[k]) % 256;
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int num2 = array[k];
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array[k] = array[num];
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array[num] = num2;
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}
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int num3;
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int num4 = (num3 = 0);
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byte[] array3 = new byte[data.Length];
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for (int l = 0; l < data.Length; l++)
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{
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num4 = (num4 + 1) % 256;
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num3 = (num3 + array[num4]) % 256;
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int num5 = array[num4];
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array[num4] = array[num3];
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array[num3] = num5;
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int num6 = array[(array[num4] + array[num3]) % 256];
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array3[l] = Convert.ToByte(data[l] ^ num6);
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}
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return array3;
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}
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}
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