asp隐藏下载地址及防盗代码

                   serv_url then
response.write "该文件不存在或者已经删除."
response.end
end if
response.redirect request.servervariables("http_referer")
response.end
end if
fileext=mid(strfilename,instrrev(strfilename, ".")+1)
select case ucase(fileext)
case "asp", "asa", "aspx", "asax", "mdb", "php", "jsp", "shtml", "html", "htm", "tv", "data"
from_url=cstr(request.servervariables("http_referer"))
serv_url=cstr(request.servervariables("server_name"))
if mid(from_url,8,len(serv_url))  serv_url then
response.write "该文件不存在或者已经删除."
response.end
end if
response.redirect request.servervariables("http_referer")
response.end
end select
set f=fso.getfile(strfilename)
intfilelength=f.size
s.loadfromfile(strfilename)
if err then
from_url=cstr(request.servervariables("http_referer"))
serv_url=cstr(request.servervariables("server_name"))
if mid(from_url,8,len(serv_url))  serv_url then
response.write "该文件数据不完整或许已损坏."
response.end
end if
response.redirect request.servervariables("http_referer")
response.end
end if
set upload=server.createobject("persits.upload")
if upload is nothing then
response.addheader "content-disposition","attachment; filename="&f.name
response.addheader "content-length",intfilelength
response.charset="utf-8"
response.contenttype="application/x-download"
response.binarywrite s.read
response.flush
s.close
set s=nothing
else
upload.sendbinary strfilename,true,"application/x-download",false
end if
end function
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