<?php
//上傳最大文件的大小。
$MAX_SIZE = 20000000;
                            
//設(shè)置允許的 Mime 類型. 
$FILE_MIMES = array('image/jpeg','image/jpg','image/gif'
                   ,'image/png','application/msword');

//設(shè)置允許的文件類型。請(qǐng)按照格式添加。            
$FILE_EXTS  = array('.zip','.jpg','.png','.gif','.wma','.rm','.wmv','.doc','.mpeg','.mp3','.avi'); 

//是否允許刪除已上傳的文件? no, 如果只允許上傳。
$DELETABLE  = no;                               


//vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
//  如果對(duì)代碼不精通，請(qǐng)不要修改以下代碼。
//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
/************************************************************
*     設(shè)置變量
************************************************************/
$site_name = $_SERVER['HTTP_HOST'];
$url_dir = "http://".$_SERVER['HTTP_HOST'].dirname($_SERVER['PHP_SELF']);
$url_this =  "http://".$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF'];

$upload_dir = "files/";
$upload_url = $url_dir."/files/";
$message ="";

/************************************************************
*     創(chuàng)建上傳目錄
************************************************************/
if (!is_dir("files")) {
  if (!mkdir($upload_dir))
   die ("upload_files directory doesn't exist and creation failed");
  if (!chmod($upload_dir,0755))
   die ("change permission to 755 failed.");
}

/************************************************************
*     用戶請(qǐng)求進(jìn)程
************************************************************/
if ($_REQUEST[del] && $DELETABLE)  {
  $resource = fopen("log.txt","a");
  fwrite($resource,date("Ymd h:i:s")."DELETE - $_SERVER[REMOTE_ADDR]"."$_REQUEST[del]\n");
  fclose($resource);
  
  if (strpos($_REQUEST[del],"/.")>0);                  //可能遭到攻擊
  else if (strpos($_REQUEST[del],"files/") === false); //可能遭到攻擊
  else if (substr($_REQUEST[del],0,6)=="files/") {
    unlink($_REQUEST[del]);
    print "<script>window.location.href='$url_this?message=deleted successfully'</script>";
  }
}
else if ($_FILES['userfile']) {
  $resource = fopen("log.txt","a");
  fwrite($resource,date("Ymd h:i:s")."UPLOAD - $_SERVER[REMOTE_ADDR]"
            .$_FILES['userfile']['name']." "
            .$_FILES['userfile']['type']."\n");
  fclose($resource);

$file_type = $_FILES['userfile']['type']; 
  $file_name = $_FILES['userfile']['name'];
  $file_ext = substr($file_name,strrpos($file_name,"."));

  //文件大小檢查
  if ( $_FILES['userfile']['size'] > $MAX_SIZE) 
     $message = "The file size is over 2MB.";
  //文件類型/擴(kuò)展名檢查
  else if (!in_array($file_type, $FILE_MIMES) 
          && !in_array($file_ext, $FILE_EXTS) )
     $message = "Sorry, $file_name($file_type) is not allowed to be uploaded.";
  else
     $message = do_upload($upload_dir, $upload_url);
  
  print "<script>window.location.href='$url_this?message=$message'</script>";
}
else if (!$_FILES['userfile']);
else 
$message = "Invalid File Specified.";

/************************************************************
*     列出文件
************************************************************/
$handle=opendir($upload_dir);
$filelist = "";
while ($file = readdir($handle)) {
   if(!is_dir($file) && !is_link($file)) {
      $filelist .= "<a href='$upload_dir$file'>".$file."</a>";
      if ($DELETABLE)
        $filelist .= " <a href='?del=$upload_dir$file' title='delete'>x</a>";
      $filelist .= "<sub><small><small><font color=grey>  ".date("d-m H:i", filemtime($upload_dir.$file))
                   ."</font></small></small></sub>";
      $filelist .="<br>";
   }
}

function do_upload($upload_dir, $upload_url) {

$temp_name = $_FILES['userfile']['tmp_name'];
$file_name = $_FILES['userfile']['name']; 
  $file_name = str_replace("\\","",$file_name);
  $file_name = str_replace("'","",$file_name);
$file_path = $upload_dir.$file_name;

//文件名字檢查
  if ( $file_name =="") { 
   $message = "Invalid File Name Specified";
   return $message;
  }

  $result  =  move_uploaded_file($temp_name, $file_path);
  if (!chmod($file_path,0755))
    $message = "change permission to 755 failed.";
  else
    $message = ($result)?"$file_name uploaded successfully." :
            "Somthing is wrong with uploading a file.";
  return $message;
}

?>

<center>
   <font color=red><?=$_REQUEST[message]?></font>
   <br>
   <form name="upload" id="upload" ENCTYPE="multipart/form-data" method="post">
     上傳文件 <input type="file" id="userfile" name="userfile">
     <input type="submit" name="upload" value="上傳">
   </form>
   
   <br><b>上傳的文件</b>
   <hr width=70%>
   <?=$filelist?>
   <hr width=70%>
</center>