public class JSDecoder { private const int STATE_COPY_INPUT = 100; private const int STATE_READLEN = 101; private const int STATE_DECODE = 102; private const int STATE_UNESCAPE = 103;
private int[] Pick_Encoding; private int[] rawData; private int[,] Transformed = new int[3, 288]; private int[] Digits = new int[123];
{
private const int STATE_COPY_INPUT = 100;
private const int STATE_READLEN = 101;
private const int STATE_DECODE = 102;
private const int STATE_UNESCAPE = 103;
private int[] Pick_Encoding;
private int[] rawData;
private int[,] Transformed = new int[3, 288];
private int[] Digits = new int[123];
public JSDecoder()
{
InitArrayData();
}
private void InitArrayData()
{
int i;
int j;
Pick_Encoding = new int[] { 1, 2, 0, 1, 2, 0, 2, 0, 0, 2, 0, 2, 1, 0, 2, 0, 1, 0, 2, 0, 1, 1, 2, 0, 0, 2, 1, 0, 2, 0, 0, 2, 1, 1, 0, 2, 0, 2, 0, 1, 0, 1, 1, 2, 0, 1, 0, 2, 1, 0, 2, 0, 1, 1, 2, 0, 0, 1, 1, 2, 0, 1, 0, 2 };
rawData = new int[] { 0x64, 0x37, 0x69, 0x50, 0x7E, 0x2C, 0x22, 0x5A, 0x65, 0x4A, 0x45, 0x72, 0x61, 0x3A, 0x5B, 0x5E, 0x79, 0x66, 0x5D, 0x59, 0x75, 0x5B, 0x27, 0x4C, 0x42, 0x76, 0x45, 0x60, 0x63, 0x76, 0x23, 0x62, 0x2A, 0x65, 0x4D, 0x43, 0x5F, 0x51, 0x33, 0x7E, 0x53, 0x42, 0x4F, 0x52, 0x20, 0x52, 0x20, 0x63, 0x7A, 0x26, 0x4A, 0x21, 0x54, 0x5A, 0x46, 0x71, 0x38, 0x20, 0x2B, 0x79, 0x26, 0x66, 0x32
, 0x63, 0x2A, 0x57, 0x2A, 0x58, 0x6C, 0x76, 0x7F, 0x2B, 0x47, 0x7B, 0x46, 0x25, 0x30, 0x52, 0x2C, 0x31, 0x4F, 0x29, 0x6C, 0x3D, 0x69, 0x49, 0x70, 0x3F, 0x3F, 0x3F, 0x27, 0x78, 0x7B, 0x3F, 0x3F, 0x3F, 0x67, 0x5F, 0x51, 0x3F, 0x3F, 0x3F, 0x62, 0x29, 0x7A, 0x41, 0x24, 0x7E, 0x5A, 0x2F, 0x3B, 0x66, 0x39, 0x47, 0x32, 0x33, 0x41, 0x73, 0x6F, 0x77, 0x4D, 0x21, 0x56, 0x43, 0x75, 0x5F
, 0x71, 0x28, 0x26, 0x39, 0x42, 0x78, 0x7C, 0x46, 0x6E, 0x53, 0x4A, 0x64, 0x48, 0x5C, 0x74, 0x31, 0x48, 0x67, 0x72, 0x36, 0x7D, 0x6E, 0x4B, 0x68, 0x70, 0x7D, 0x35, 0x49, 0x5D, 0x22, 0x3F, 0x6A, 0x55, 0x4B, 0x50, 0x3A, 0x6A, 0x69, 0x60, 0x2E, 0x23, 0x6A, 0x7F, 0x9, 0x71, 0x28, 0x70, 0x6F, 0x35, 0x65, 0x49, 0x7D, 0x74, 0x5C, 0x24, 0x2C, 0x5D, 0x2D, 0x77, 0x27, 0x54, 0x44, 0x59
, 0x37, 0x3F, 0x25, 0x7B, 0x6D, 0x7C, 0x3D, 0x7C, 0x23, 0x6C, 0x43, 0x6D, 0x34, 0x38, 0x28, 0x6D, 0x5E, 0x31, 0x4E, 0x5B, 0x39, 0x2B, 0x6E, 0x7F, 0x30, 0x57, 0x36, 0x6F, 0x4C, 0x54, 0x74, 0x34, 0x34, 0x6B, 0x72, 0x62, 0x4C, 0x25, 0x4E, 0x33, 0x56, 0x30, 0x56, 0x73, 0x5E, 0x3A, 0x68, 0x73, 0x78, 0x55, 0x9, 0x57, 0x47, 0x4B, 0x77, 0x32, 0x61, 0x3B, 0x35, 0x24, 0x44, 0x2E, 0x4D
, 0x2F, 0x64, 0x6B, 0x59, 0x4F, 0x44, 0x45, 0x3B, 0x21, 0x5C, 0x2D, 0x37, 0x68, 0x41, 0x53, 0x36, 0x61, 0x58, 0x58, 0x7A, 0x48, 0x79, 0x22, 0x2E, 0x9, 0x60, 0x50, 0x75, 0x6B, 0x2D, 0x38, 0x4E, 0x29, 0x55, 0x3D, 0x3F };
for (i = 31; i <= 126; i++)
{
for (j = 0; j <= 2; j++)
{
Transformed[j, rawData[(i - 31) * 3 + j]] = i == 31 ? 9 : i;
}
}
for (i = 0; i <= 25; i++)
{
Digits[65 + i] = i;
Digits[97 + i] = i + 26;
}
for (i = 0; i <= 9; i++)
{
Digits[48 + i] = i + 52;
}
Digits[43] = 62;
Digits[47] = 63;
}
private string UnEscape(string strChar)
{
string escapes;
string escaped;
int iIndex;
escapes = "#&!*$";
escaped = '\r' + '\n' + "<>@";
if (Strings.AscW(strChar.Substring(0, 1)) > 126)
{
return strChar;
}
iIndex = escapes.IndexOf(strChar);
if (iIndex != - 1)
{
return escaped.Substring(iIndex, 1);
}
return "?";
}
private int DecodeBase64(string strString)
{
int iVal = 0;
iVal += Digits[Strings.AscW(strString.Substring(0, 1))] << 2;
iVal += Digits[Strings.AscW(strString.Substring(1, 1))] >> 4;
iVal += (Digits[Strings.AscW(strString.Substring(1, 1))] & 0xF) << 12;
iVal += (Digits[Strings.AscW(strString.Substring(2, 1))] >> 2) << 8;
iVal += (Digits[Strings.AscW(strString.Substring(2, 1))] & 0x3) << 22;
iVal += Digits[Strings.AscW(strString.Substring(3, 1))] << 16;
return iVal;
}
public string Decode(string encodingString)
{
string unEncodingString = "";
string Pattern; unEncodingString = DecodeProcedure(encodingString);
Pattern = "(JScript|VBscript).encode";
unEncodingString = System.Text.RegularExpressions.Regex.Replace(unEncodingString, Pattern, "$1", System.Text.RegularExpressions.RegexOptions.IgnoreCase);
return unEncodingString;
} private string DecodeProcedure( string encodingString)
{
string er = "#@~^";
int stringIndex = 0;
int scriptIndex = - 1;
int unEncodingIndex = 0;
string strChar = "";
string getCodeString = "";
int unEncodinglength = 0;
int state = 100;
string unEncodingString = "";
while (state != 0)
{
switch (state)
{
case STATE_COPY_INPUT:
if (stringIndex<0 || stringIndex >= encodingString.Length)
{
state = 0;
return unEncodingString;
}
scriptIndex = encodingString.IndexOf(er, stringIndex);
if (scriptIndex != - 1)
{
if (stringIndex+1-1<0 || scriptIndex - stringIndex >= encodingString.Length)
{
state = 0;
return unEncodingString;
}
unEncodingString += encodingString.Substring(stringIndex + 1 - 1, scriptIndex - stringIndex);
scriptIndex += er.Length;
state = STATE_READLEN;
}
else
{
if ( stringIndex+1-1<0 || stringIndex+1-1 >=encodingString.Length)
{
state = 0;
return unEncodingString;
}
stringIndex = stringIndex == 0 ? 0 : stringIndex;
unEncodingString += encodingString.Substring(stringIndex + 1 - 1);
state = 0;
}
break;
case STATE_READLEN:
if ( stringIndex+1-1<0 || stringIndex+1-1 >=encodingString.Length)
{
state = 0;
return unEncodingString;
}
getCodeString = encodingString.Substring(scriptIndex + 1 - 1, 6);
unEncodinglength = DecodeBase64(getCodeString);
scriptIndex += 8;
state = STATE_DECODE;
break;
case STATE_DECODE:
if (unEncodinglength == 0)
{
stringIndex = scriptIndex + "DQgAAA==^#~@".Length;
unEncodingIndex = 0;
state = STATE_COPY_INPUT;
}
else
{
if ( stringIndex+1-1<0 || scriptIndex + 1 - 1 >= encodingString.Length )
{
state = 0;
return unEncodingString;
}
strChar = encodingString.Substring(scriptIndex + 1 - 1, 1);
if (strChar == "@")
{
state = STATE_UNESCAPE;
unEncodingString += UnEscape(encodingString.Substring(scriptIndex + 2 - 1, 1));
scriptIndex += 2;
unEncodinglength -= 2;
unEncodingIndex++;
state = STATE_DECODE;
}
else
{
if (Strings.AscW(strChar) < 0xFF)
{
unEncodingString += Strings.Chr(Transformed[Pick_Encoding[unEncodingIndex % 64], Strings.AscW(strChar)]);
unEncodingIndex++;
}
else
{
unEncodingString += strChar;
}
scriptIndex++;
unEncodinglength--;
}
}
break;
case STATE_UNESCAPE:
if ( stringIndex+1-1<0 )
{
state = 0;
return unEncodingString;
}
unEncodingString += UnEscape(encodingString.Substring( ++scriptIndex - 1, 1));
scriptIndex++;
unEncodinglength -= 2;
unEncodingIndex++;
state = STATE_DECODE;
break;
}
}
return unEncodingString;
}
}