PHP上传MIME类型限制

Question

I have a file upload system in a site which allows upload of .doc, .docs and .pdf files. Currently the PHP script allows upload of any file type. I would like to restrict it to only allow uploading of genuine PDF DOC and DOCX files. I have read that this is best done via checking the MIME type / headers of the file - but cant seem to find an agreed best solution to do this anywhere.

Any tips on the best way to achieve this?

Current upload PHP is:

$meta = $dropbox->UploadFile($_FILES["fileInputFieldName"]["tmp_name"], $upload_name);

Appreciate any tips on how to integrate this into the suggestions please.

Answer 1

Why dont you try the below code

$sys = mime_content_type($_FILES["fileToUpload"]["tmp_name"]);
if($sys == 'application/x-zip' || $sys == 'application/msword'){
    echo ' allowed';
}else{
    echo 'not allowed';
}

Answer 2

I used this in the end for those interested:

$allowedExts = array(
  "pdf", 
  "doc", 
  "docx"
); 

$allowedMimeTypes = array( 
  'application/msword',
  'application/pdf',
  'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
  'application/x-pdf',
  'application/vnd.pdf',
  'text/pdf'
);

$extension = end(explode(".", $_FILES["file"]["name"]));

if ( ! ( in_array($extension, $allowedExts ) ) ) {
  die('Please provide another file type [E/2].');
}

if ( in_array( $_FILES["file"]["type"], $allowedMimeTypes ) ) 
{      
 move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); 
}
else
{
die('Please provide another file type [E/3].');
}

Answer 3

that is how i restrict extension for image, you can apply this for doc and other files you want.. 

 "i converted $_FILES to $file"

if ($file['profile_pic']['error'] == 0) {
                                         // echo 'hello';
                                $fileName = strtolower($file['profile_pic']['name']);
                                $fileType = $file['profile_pic']['type'];
                                $tempName = $file['profile_pic']['tmp_name'];
                                $fileSize = $file['profile_pic']['size'];

                                $fileExtArray = array('image/jpeg', 'image/jpg', 'image/png', 'image/gif', 'public.jpeg');
                                $random_no = mt_rand() * 64;
                                $uploaddir = '../../Application/img/';
                                $file_name = $random_no . "_profile_" . $_FILES['profile_pic']['name'];
                                $image = $uploaddir . basename($file_name);
                                if (in_array($fileType, $fileExtArray))
                                    move_uploaded_file($_FILES['profile_pic']['tmp_name'], $image);
                          }

Answer 4

            $allowedExts = array("bmp", "gif", "jpg","png","jpeg");
                            $RandomNum   = rand(0, 9999);           
                            $ImageName      = str_replace(' ','-',strtolower($_FILES['uploadedimage']['name']));
                            $ImageType      = $_FILES['uploadedimage']['type']; //"document/txt", document/doc etc.
                            $ImageExt = substr($ImageName, strrpos($ImageName, '.'));
                            $ImageExt = str_replace('.','',$ImageExt);
                            if (!empty($_FILES["uploadedimage"]["name"]))
                            {
                                if(!in_array($ImageExt, $allowedExts))
                                {
                                    $message.="<span class='error-message'>Invalid file format of image, only <b>'bmp', 'gif', 'jpg','png','jpeg'</b> allowed.</span><br>";
                                }
                            }
                            if(isset($message) && $message=='')
                            {
                                //image
                                $temp_name=$_FILES["uploadedimage"]["tmp_name"];
                                $imagename=time().'-'.$ImageName;
                                $target_path = "../profile-images/".$imagename;
                                $_SESSION['message']=$message;  
                                }