[Original] ASP Security Detection and filtering function SafeCheck

'--------------------------------------------------------------------------
'Role: Security string Detection Function
'Name: safecheck
'Parameter: checkstring, checktype, checklength
'Note:
'Checkstring string to be detected: any character.
'Checktype detection Type 0 normal short character 1 digit 2 date 3 money 4 encoding HTML5 decoding html6 login string 7 attack prevention detection
'Checklength detection type length: int type, decimal point when it is money
'Return value: If detection is successful, the correct string is returned,
'The error code system_error | error_code is returned if it fails.
'Script writen by: snowdu (Du Xue. Net)
'Web: http://www.snsites.com/
'--------------------------------------------------------------------------
Function safecheck (checkstring, checktype, checklength)
On Error resume next
Errorroot = "system_error |"
If checkstring = "" then
Safecheck = errorroot & "00001"
Exit Function
End if

CheckString = Replace (CheckString, "'", "& #39 ")
Select case CheckType
Case 0
CheckString = trim (CheckString)
SafeCheck = Left (CheckString, CheckLength)
Case 1
If not isnumberic (CheckString) then
SafeCheck = ErrorRoot & "00002"
Exit function
Else
SafeCheck = Left (CheckString, CheckLength)
End if
Case 2
TempVar = IsDate (CheckString)
If Not TempVar then
SafeCheck = ErrorRoot & "00003"
Exit function
Else
Select case CheckLength
Case 0
SafeCheck = FormatDateTime (CheckString, vb1_date)
Case 1
SafeCheck = FormatDateTime (CheckString, vbLongDate)
Case 2
SafeCheck = CheckString
End select
End if
Case 3
TempVar = FormatCurrency (CheckString, 0)
If Err then
SafeCheck = ErrorRoot & "00004"
Exit function
Else
SafeCheck = FormatCurrency (CheckString, CheckLength)
End if
Case 4
STemp = CheckString
If IsNull (sTemp) = True Then
SafeCheck = ErrorRoot & "00005"
Exit Function
End If
STemp = Replace (sTemp, "&", "& amp ;")
STemp = Replace (sTemp, "<", "& lt ;")
STemp = Replace (sTemp, ">", "& gt ;")
STemp = Replace (sTemp, Chr (34), "& quot ;")
STemp = Replace (sTemp, Chr (10), "<br> ")
SafeCheck = Left (sTemp, CheckLength)
Case 5
STemp = CheckString
If IsNull (sTemp) = True Then
SafeCheck = ErrorRoot & "00006"
Exit Function
End If
STemp = Replace (sTemp, "& amp ;","&")
STemp = Replace (sTemp, "& lt;", "<")
STemp = Replace (sTemp, "& gt;", "> ")
STemp = Replace (sTemp, "& quot;", Chr (34 ))
STemp = Replace (sTemp, "<br>", Chr (10 ))
SafeCheck = Left (sTemp, CheckLength)
Case 6
S_BadStr = "'& <>? % ,;:()'~! @ # $ ^ * {} [] | +-= "& Chr (34) & Chr (9) & Chr (32)
N = Len (s_BadStr)
IsSafeStr = True
For I = 1 To n
If Instr (CheckString, Mid (s_BadStr, I, 1)> 0 Then
IsSafeStr = False
End If
Next
If IsSafeStr then
SafeCheck = left (CheckString, CheckLength)
Else
SafeCheck = ErrorRoot & "00007"
Exit Function
End if
Case 7
S_Filter = "net user | xp_mongoshell |/add | select | count | asc | char | mid | '|" "|"
S_Filter = S_Filter & "insert | delete | drop | truncate | from | % | declare | -"
S_Filters = split (S_Filter, "| ")
IsFound = false
For I = 0 to ubound (S_Filters)-1
If Instr (lcase (CheckString), lcase (S_Filters (I) <> 0 then
IsFound = true
Exit
End if
Next
If isFound then
SafeCheck = ErrorRoot & "00008"
Exit Function
Else
SafeCheck = left (CheckString, CheckLength)
End if
End select
End function