Web Hosting Server Permissions

[LodBot]

For the past few years I've been providing my friends with webspace. Each user connects through ftp to update their content. I run pure-ftpd with mysql authentication and there is a system link in their home directories that guides them to their public html directory. This setup has worked great for me. The only security issue that I've noticed involves php scripts. So lets say my http root directory is /var/www/localhost/htdocs, user1's public html folder is /var/www/localhost/htdocs/user1/public_html and user2's public html folder is /var/www/localhost/htdocs/user2/public_html. I can't figure out a way that prohibits user1 from accessing user2's information via a php script. I've only been hosting my friends, so I've never worried about users accessing other users' information. Lately, though, I've been asked by a few strangers (not really strangers but people I don't know that well) for webspace. I want to make sure that these users can't access my http root directory as well as other peoples'. I'm assuming that my solution will have something to do with permission, but I'm not entirely sure and I can't figure out a way to do it.

I've thought about writing a script that opens every .php file and checks to make sure that the php file isn't accessing data it shouldn't be, but I figured their would be an easier way.

Also, can php scripts access any system commands that might cause damage? i.e. #rm and #mv.

Thanks in advance.

[yaneurabeya]

If the directories are owned by users who are not the same users that PHP is running under (since I believe PHP scripts run as the apache user with group www, but don't quote me on that >_<), if you setup the owning user for each directory to be different and/or separate from each other, it should run perfectly fine without perms issues. I don't know exactly how, but my school does it perfectly fine with hundreds of users, so it can be done easily I suppose. I will look into their httpd.conf file...

PHP scripts can only cause as much damage as the owning user can supply via a terminal. That's partly why apache/PHP doesn't run as root I would assume .