Mob Script Encryption Algorithm

[Jet]

Visual Basic code:
Translated by CAHEK7

Код:

Public Sub ScriptCrypt(ByRef Script() As Byte, ByVal Key As Long)

Dim Tmp As Double
Dim i As Long
Dim TmpLng As Long
Tmp = Key

For i = 0 To UBound(Script)

  Tmp = Tmp * 214013 + 2531011
'-------------------------------------------------
     Do While Tmp > 2199023255552#
       Tmp = Tmp - 2199023255552#
     Loop
     Do While Tmp > 274877906944#
       Tmp = Tmp - 274877906944#
     Loop
     Do While Tmp > 34359738368#
       Tmp = Tmp - 34359738368#
     Loop
     Do While Tmp > 4294967296#
       Tmp = Tmp - 4294967296#
     Loop
' Especially to convert Double to DWORD
' you can change number of cycles
' to change up execution speed
'-------------------------------------------------

  TmpLng = CLng(Int(Tmp / 65536))
  TmpLng = TmpLng Mod 256
 
  Script(i) = Script(i) Xor CByte(TmpLng)

Next

End Sub

C# Code:

Код:

public string ReadCodedString()
{
byte[] coded = new byte[DataSize - 4];     // sizeof(coded string) - sizeof(key)
char[] decoded = new char[coded.Length];
uint uKey;

// Read
uKey   = orStream.ReadUInt32();           // KEY
coded = orStream.ReadBytes(coded.Length); // Coded string

// Decode string
for(int i = 0; i < coded.Length; i++)
{
  uKey = uKey * 214013 + 2531011;
  decoded[i] = Convert.ToChar(coded[i] ^ Convert.ToByte(uKey / 65536 % 256));
}
return new string(decoded, 0, decoded.Length );
}