如何从 php 脚本执行 shell 命令

Question

I would like to create a php script to execute a shell command and return its output. The server requires a private key. When I first decided to test this out I created this:

<?php
$command = "ls";
$output = shell_exec($command);
echo "<pre>$output</pre>";
?>

That worked just fine. But when I changed $command to the command I really wanted to run:

$command = "/etc/init.d/mycontrollerd status /etc/mycontrollerconfig";

it gave me this output:

You need root privileges to run this script

My guess is I need to use sudo . Of course that will require putting the pem file somewhere on the server. Assuming I do that, what exactly should $command be? Should I use shell_exec() , exec() , system() or something else?

Answer 1

It does not matter which php function you use to start the script - what lacks is the authorization of your user account.

Either use sudo (preconfigure the web server user to run the exact command without password via visudo , and prefix the command with sudo ) or set up a setuid script that executes the command on itself.

Answer 2

What you really need to do is set your web server to run as a specific user (other than 'nobody' for example), or give that user permissions to what you want to execute.

See also: PHP shell_exec() and sudo: must be setuid root