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phpunixposix

When running as root, how can I make PHP create files with a specific group?

I have a PHP script which runs as root. The script creates some files, and those files should be owned by a specified user and group. I have managed to make the script create the files with the correct owner, however, the group associated with the files is still root.

Here's a proof-of-concept for what I'm doing:

$userInfo = posix_getpwnam('eric');
posix_initgroups($userInfo['name'], $userInfo['gid']);
posix_setuid($userInfo['uid']);

file_put_contents('test.txt', 'Some content');

Then I run it as root:

sudo php test.php

It creates a file that is tied to the root group:

Access: (0644/-rw-r--r--)  Uid: ( 1000/    eric)   Gid: (    0/    root)

How can I force PHP to create files with the correct Gid?

Side note: The script needs to be able to run as root, and running with su - $user is not an option in my scenario.

Solution

  • You could use chgrp() after the fact or try the same posix methodology but with the group: posix_setgid().

    The appropriate order of function calls is posix_setgid() first, posix_setuid() last.