make it possible to run occ as root

[karlitschek]

make it possible to run as root

To do

• Start non privileged child process
• Handle exit codes
• Handle STDIN/STDOUT/STDERR streams

[karlitschek]

@CarlSchwan @PVince81 @nickvergessen @AndyScherzinger

[nickvergessen]

Suggested change

	if (posix_getuid() == 0){
	$command = implode (' ', $argv);
	echo(shell_exec('sudo -u www-data '.$command));
	if (posix_getuid() === 0) {
	$command = implode (' ', $argv);
	echo shell_exec('sudo -u www-data ' . $command);

return code is being killed

[nickvergessen]

Maybe can use exec instead:

https://github.com/nextcloud/spreed/blob/84d42604e60aa1c31ecf698dcc069f36c494148a/lib/Chat/Command/ShellExecutor.php#L66-L74

[nickvergessen]

Maybe can use exec instead:

https://github.com/nextcloud/spreed/blob/84d42604e60aa1c31ecf698dcc069f36c494148a/lib/Chat/Command/ShellExecutor.php#L66-L74

[tcitworld]

www-data might not be the default user name for the HTTP server though, mostly only Debian-based systems use that. RedHat-based systems or ArchLinux use an user named http by default.

Also, does this forwards environment variables?

[PVince81]

what we do in other places is read the user name from the config file, basically the owner of "config/config.php" and use that to check if the correct user is being used

[tcitworld]

This makes sense unless config_is_read_only is used, then the config file owner could be something irrelevant such as root, as long as the http server user has read access.

[nickvergessen]

Well in worst case you can not use the root shortcut then and need to manually sudo -u yourwebserver-user occ ?

[AndyScherzinger]

@karlitschek I believe we can close this PR since it was originally planned/needed as a pre-requisite for Nc Guard, right?

[ChristophWurst]

Finding the right user is doable from config.php ownership guessing.

The tricky part is STDIN/STDOUT/STDERR handling. Neither with shell_exec nor proc_open I was able to connect the parent process pipes with the child process. shell_exec makes the parent block when occ asks for input (e.g. when you make a typo or when it needs confirmation).

I've pushed some fixes that make this work on a non-Debian system too.