使用PHP mkdir（）创建用户组目录时要使用什么chmod权限

Question

-

• A PHP Web application, needs to allow logged in admins to upload and delete images to a web folder, for a particular record.

• When a record is created in a MySQL database, a folder is also created on the public server - using PHP mkdir() - to hold images for that particular record.

• There will be multiple users of the same application, all needing permission to add and delete images to the folders being created.

• The folder would need to continue to be accessible via FTP as well.

So I guess that overall, it needs to be accessible - add, edit, delete, view, FTP - by logged in users, but not accessible to the general public.

What folder permission should I use for this?

Reasons why? Security? Accessibility? Edit-ability?

Thanks. Regards.

Answer 1

When uploading files using a web interface your upload directory needs to be writable by the apache user. If all interaction with the files are going to be through a web interface, you just need to worry about the apache user, and the other groups would be authenticated via the web application.

If you are creating folders and then allowing users and groups to access the files from the server you need to make the groups. In this case make an admin group.

Steps:

//make the admin group
$ groupadd admin

// make the folder for uploads
$ sudo mkdir uploads

// make the apache user (apache or www-data) the owner and the group admin
$ chown apache.admin uploads

// give the folder permission using the sticky bit
// this will allow both apache and admin group to edit/add/delete in uploads
$ chmod 7752 uploads

// the sticky bit will maintain the group inside the uploads folder
// try it out
$ su apache
$ cd uploads
$ mkdir test
$ touch newFile.txt

// the new folder and new file should have admin as the group

Without the sticky bit the new files and folders in uploads will be owned by apache and the apache group. ie... chmod 775 test

Now when you make new folders in the uploads folder users that are in the admin group will have ftp access to them