public static string GET_GTK(string skey)
{
var arg = "tencentQQVIP123443safde&!%^%1282";
var list = new List <int>();
var num = 5381;
list.Add(172192);
var i = 0;
for (var length = skey.Length; i < length; i++)
{
int num2 = Encoding.UTF8.GetBytes(skey)[i];
list.Add((num << 5) + num2);
num = num2;
}
var stringBuilder = new StringBuilder();
for (i = 0; i < list.Count; i++)
{
stringBuilder.Append(list[i].ToString());
}
return(QQTea.Md5(stringBuilder + arg));
}
private static void code(byte[] In, int inOffset, int inPos, byte[] Out, int outOffset, int outPos, byte[] key)
{
if (outPos > 0)
{
for (int i = 0; i < 8; i++)
{
In[outOffset + outPos + i] = System.BitConverter.GetBytes(In[inOffset + inPos + i] ^ Out[outOffset + outPos + i - 8])[0];
}
}
uint[] array = QQTea.FormatKey(key);
uint num = QQTea.ConvertByteArrayToUInt(In, outOffset + outPos);
uint num2 = QQTea.ConvertByteArrayToUInt(In, outOffset + outPos + 4);
uint num3 = 0u;
uint num4 = 2654435769u;
uint num5 = 16u;
while (num5-- > 0u)
{
num3 += num4;
num += ((num2 << 4) + array[0] ^ num2 + num3 ^ (num2 >> 5) + array[1]);
num2 += ((num << 4) + array[2] ^ num + num3 ^ (num >> 5) + array[3]);
}
Array.Copy(QQTea.ConvertUIntToByteArray(num), 0, Out, outOffset + outPos, 4);
Array.Copy(QQTea.ConvertUIntToByteArray(num2), 0, Out, outOffset + outPos + 4, 4);
if (inPos > 0)
{
for (int j = 0; j < 8; j++)
{
Out[outOffset + outPos + j] = System.BitConverter.GetBytes(Out[outOffset + outPos + j] ^ In[inOffset + inPos + j - 8])[0];
}
}
}
private static uint[] FormatKey(byte[] key)
{
if (key.Length == 0)
{
throw new ArgumentException("Key must be between 1 and 16 characters in length");
}
byte[] array = new byte[16];
if (key.Length < 16)
{
Array.Copy(key, 0, array, 0, key.Length);
for (int i = key.Length; i < 16; i++)
{
array[i] = 32;
}
}
else
{
Array.Copy(key, 0, array, 0, 16);
}
uint[] array2 = new uint[4];
int num = 0;
for (int j = 0; j < array.Length; j += 4)
{
array2[num++] = QQTea.ConvertByteArrayToUInt(array, j);
}
return(array2);
}
public static byte[] Encrypt(byte[] In, int offset, int len, byte[] key)
{
Random random = new Random();
int num = (len + 10) % 8;
if (num != 0)
{
num = 8 - num;
}
byte[] array = new byte[len + num + 10];
array[0] = (byte)((random.Next() & 248) | num);
for (int i = 1; i < num + 3; i++)
{
array[i] = (byte)(random.Next() & 255);
}
Array.Copy(In, 0, array, num + 3, len);
for (int j = num + 3 + len; j < array.Length; j++)
{
array[j] = 0;
}
byte[] array2 = new byte[len + num + 10];
for (int k = 0; k < array2.Length; k += 8)
{
QQTea.code(array, 0, k, array2, 0, k, key);
}
return(array2);
}
public static byte[] Decrypt(byte[] In, int offset, int len, byte[] key)
{
var temp = new byte[In.Length];
Buffer.BlockCopy(In, 0, temp, 0, In.Length);
if (len % 8 != 0 || len < 16)
{
return(null);
}
byte[] array = new byte[len];
for (int i = 0; i < len; i += 8)
{
QQTea.decode(temp, offset, i, array, 0, i, key);
}
for (int j = 8; j < len; j++)
{
array[j] ^= temp[offset + j - 8];
}
int num = (int)(array[0] & 7);
len = len - num - 10;
byte[] array2 = new byte[len];
Array.Copy(array, num + 3, array2, 0, len);
return(array2);
}
public static byte[] Decrypt(byte[] In, int offset, int len, byte[] key)
{
if (len % 8 != 0 || len < 16)
{
return(null);
}
byte[] array = new byte[len];
for (int i = 0; i < len; i += 8)
{
QQTea.decode(In, offset, i, array, 0, i, key);
}
for (int j = 8; j < len; j++)
{
array[j] ^= In[offset + j - 8];
}
int num = (int)(array[0] & 7);
len = len - num - 10;
byte[] array2 = new byte[len];
Array.Copy(array, num + 3, array2, 0, len);
return(array2);
}
