Question

ASP 防SQL注入过滤代码问题？？

function checkstr(str)
if isnull(str) then
checkstr = ""
exit function
end if
str = replace(str,chr(0),"", 1, －1, 1)
str = replace(str, """", """, 1, －1, 1)
str = replace(str,"<；","<；", 1, －1, 1)
str = replace(str,">；",">；", 1, －1, 1)
str = replace(str, "script", "script", 1, －1, 0)
str = replace(str, "script", "script", 1, －1, 0)
str = replace(str, "script", "script", 1, －1, 0)
str = replace(str, "script", "script", 1, －1, 1)
str = replace(str, "object", "object", 1, －1, 0)
str = replace(str, "object", "object", 1, －1, 0)
str = replace(str, "object", "object", 1, －1, 0)
str = replace(str, "object", "object", 1, －1, 1)
str = replace(str, "applet", "applet", 1, －1, 0)
str = replace(str, "applet", "applet", 1, －1, 0)
str = replace(str, "applet", "applet", 1, －1, 0)
str = replace(str, "applet", "applet", 1, －1, 1)
str = replace(str, "[", "[")
str = replace(str, "]", "]")
str = replace(str, """", "", 1, －1, 1)
str = replace(str, "=", "=", 1, －1, 1)
str = replace(str, "’", "’’", 1, －1, 1)
str = replace(str, "select", "select", 1, －1, 1)
str = replace(str, "execute", "execute", 1, －1, 1)
str = replace(str, "exec", "exec", 1, －1, 1)
str = replace(str, "join", "join", 1, －1, 1)
str = replace(str, "union", "union", 1, －1, 1)
str = replace(str, "where", "where", 1, －1, 1)
str = replace(str, "insert", "insert", 1, －1, 1)
str = replace(str, "delete", "delete", 1, －1, 1)
str = replace(str, "update", "update", 1, －1, 1)
str = replace(str, "like", "like", 1, －1, 1)
str = replace(str, "drop", "drop", 1, －1, 1)
str = replace(str, "create", "create", 1, －1, 1)
str = replace(str, "rename", "rename", 1, －1, 1)
str = replace(str, "count", "count", 1, －1, 1)
str = replace(str, "chr", "chr", 1, －1, 1)
str = replace(str, "mid", "mid", 1, －1, 1)
str = replace(str, "truncate", "truncate", 1, －1, 1)
str = replace(str, "nchar", "nchar", 1, －1, 1)
str = replace(str, "char", "char", 1, －1, 1)
str = replace(str, "alter", "alter", 1, －1, 1)
str = replace(str, "cast", "cast", 1, －1, 1)
str = replace(str, "exists", "exists", 1, －1, 1)
str = replace(str,chr(13),"<；br>；", 1, －1, 1)
checkstr = replace(str,"’","’’", 1, －1, 1)
end function
这代码可以防止SQL注入吗？ 怎么用呢？
具体用在哪地方？？听说很多ASP 网站被黑
如何才能防止？
祥细点吧

Answer 1

不用这样，如果你的变量是数字型，那用Clng()转一下，如果是日期类型， CDate()一下，如果是其他类型，把单引号替换了就行：
Function checkStr(ByVal x, ByVal typ)
On Error Rusume Next

'如果你是需要整形变量
If typ = "int" Then
x = Clng(x)

'如果你是需要时间
Else If typ = "date" Then
x = CDate(x)

'其他
Else
x = Replace(x, "'", "''")
End If
If Err.Number <> 0 Then
Response.End()
End If

checkStr = x
End Function
这样就可以了，肯定注入不了

Answer 2

用在能够被接受到参数的地方
主要是
request.form
request.querystring
request.cookie
这三种类型的变量都有可能会被恶意注入
你原来的一些地方写法可能是
aaa=request.querystring("aaa")
用这个函数就要变成
aaa=checkstr(request.querystring("aaa"))

你直接找一个asp防注入通用的吧
直接包含在conn文件里面即可

Answer 3

checkstr(request("fuckhacker"))