I'm working on creating my own little Website to manage a Minecraft server as fun project. Now what I would need to accomplish is being able to send commands to the screen in which the server is running.
My approach to this was the following:
<?php
if (isset($_POST['startbutton']))
{
exec('sudo screen -S 23971 -X stuff "say hello^M"');
}
?>
<form method="post">
<button type="submit" name="startbutton">Test</button>
</form>
Now that command line works just fine when i execute it in the terminal itself, but as soon as i try to run it over the Website nothing happens.
If i just try to execute
if (isset($_POST['startbutton']))
{
echo exec('whoami');
}
?>
it works just fine as well. I don't know what I am doing wrong.
i'm really not sure about it, but try:
<?php
if (isset($_POST['startbutton']))
{
exec('sudo screen -S 23971 -X stuff "say hello^M"');
exec('YOUR SUDO PSW');
}
?>
<form method="post" action="YOUR PHP PAGE LIKE server.php">
<button type="submit" name="startbutton">Test</button>
</form>
let me know if it works
Seems like you are trying to execute a command that needs superuser permissions. In most setups PHP runs under the webserver user and it does not have those permissions. Also you should keep in mind that giving superuser permissions to PHP is a security risk.
My suggestion would be to have a dedicated service, responsible for executing those shell commands. You could then call that service from your PHP script without needing sudo.
Check these for details:
https://serverfault.com/questions/622271/securely-executing-system-commands-as-sudo-from-php/622277
sudo in php exec()
First of all: Thank you all for your support.
I was doing a bit of further research and found a solution for my problem:
I created a new user which I then gave the ownership of /var/www.
I then changed the apache2 user from www-data to the new user.
Now i just needed to start the screen with the minecraft server as the new user so i can access this screen out of php and I was able to get it to work without having to give any user full root privileges or anything.
Related
After opening and reading every result on Google, I figured it's time to make my own thread somewhere. I am sorry that I need to ask a question that's already been asked before, I cannot stress this enough, but I have no other option as no other question asked has helped me achieve what my goal is.
I'm trying to setup a means of rebooting/doing other system functions through a web interface powered by HTML (for the buttons/text) and PHP (for the execution of the aforementioned functions).
I'm unable to get this to work. I've read that I need to add the web user to the sudoers file, and I've tried. I'm running Nginx on my server, how do I add the user to the sudoers in my case?
Also, I'm aware of the security risks.
The following is what I have so far:
HTML (index.html):
<body>
<h3>Restart</h3>
<p>
<form action="restart.php" method="get">
<input type="submit" value="Press me.">
</form>
</p>
</body>
PHP (restart.php):
<?php
echo "This is a test";
echo "<br>";
echo "<br>";
echo shell_exec('ifconfig');
echo "<br>";
echo "<br>";
echo "Restarting server...";
exec ('/usr/bin/sudo /etc/init.d/portmap restart');
shell_exec("/sbin/reboot");
exec("/sbin/reboot");
system("/sbin/reboot");
?>
Mind you that here, I only have so many things attempting to execute, so that I make sure I hit the target when one of them works, if that makes sense. The IFConfig is just a test to make sure that it's actually able to execute.
Sudoers:
# User privilege specification
root ALL=(ALL:ALL) ALL
www-data reboot = NOPASSWD: /sbin/reboot
This is all on Ubuntu 14.04 LEMP.
You can do this either by editing your sudoers file :
Sudoers:
www-data ALL=(root) NOPASSWD: /sbin/reboot
The first ALL is for the hostname if you're hostname is not 'reboot' I advise you to keep ALL as it will work in any hostname. That's why it doesn't seem to work on your server
restart.php
exec('sudo /sbin/reboot');
Or without editing your sudoers file.
First create a file where you're gonna store you're root password
~/password :
myrootpassword
Second run any command you want while being root from php file (don't forget to specify the file which store your password)
phpfile.php :
exec('sudo -u root -S /sbin/reboot < ~/password');
www-data reboot = NOPASSWD: /sbin/reboot
this means you dont need a password when running sudo, not that the command runs as sudo when ever run by that user.
The answer is to use sudo /sbin/reboot as the command
You can use puty. I think using php is not a good plan.
I have a generate.php page
<?php
exec("./script $ip");
?>
I have verified that the the variable $ip is pulling from the URL correctly. When it redirects to this page it does not run the script. I have also tried to verify that the script works for the apache user and it does.
su -s /bin/sh apache -c "./script 1.1.1.1"
The code that sets the IP from my index.html page is this
<form action="generate.php">
<input type="text" name="ip" />
<input type="submit" />
</form>
When I enter the IP into the box and hit submit, it does take me to http://example.com/generate.php?ip=1.1.1.1
Is there something wrong with the way I am invoking the shell script? Any input will be greatly appreciated.
Thank you for all the input, turned out to be just selinux. Disabling selinux solved this issue. Since this is not a network connected system, selinux being disabled is not an issue.
su -s /bin/sh apache -c "./script 1.1.1.1"
You are executing the script with root privileges.
Try executing the script with your user and see the results. You maybe need to add permissions to the file.
Also by default exec function is disabled for security reasons. You can try edit the configuration file.
Also the php error log file will be helpful to read.
Other than that the whole idea is really bad. Executing shell scripts with parameters from GET or POST may lead to bad things...
You may try this:
<?php
if (isset($_GET['ip'])) {
exec('./script ' + $_GET['ip']);
} else {
exec("./script $ip");
}
Here you will use ip from URL (like: http://example.com/generate.php?ip=1.1.1.1) in case it's provided, otherwise you will use your previous implementation.
I want to restart mysql service on click of the button using php.
I have developed application using php till now I tried below things and facing the problem
<?php
if ($_GET['run']) {
# This code will run if ?run=true is set.
var_dump(exec("sh rst.sh"));
exit;
}
?>
<!-- This link will add ?run=true to your URL, myfilename.php?run=true -->
Click Me!
What I am getting is:
string(55) "Restarting mysql (via systemctl): mysql.service failed!"
rest.sh:
#!/bin/bash
/etc/init.d/mysql restart
while executing above file from the commnad line it asks for the password.
any help will be appreciated.
Thanks
Granting the user that runs PHP/web server permissions to restart any service is generally a bed idea from security perspective not even taking about permission to manage all system daemons or full sudo.
Once you have been warned, you have to make sure the user that is running the PHP script has the permission to run the restart command. As already stated, the issue has likely little to do with PHP. There are several ways from you to proceed here:
You can grant the PHP user the sudo permission to run the desired command and nothing else (how to do that is covered elsewhere) and invoke the command directly from PHP: sudo systemctl restart mysql.
Keep the rst.sh file, get it owned by root, writeable by noone else but root and set SUID bit on that file. This way you can invoke the script without sudo but the script will be run as root thanks to the SUID bit.
#1 feels safer and simpler.
You could also try with system():
<?php
if ($_GET['run']) {
# This code will run if ?run=true is set.
var_dump(system("sh rst.sh"));
exit;
}
?>
<!-- This link will add ?run=true to your URL, myfilename.php?run=true -->
Click Me!
Though your problem is coming from the script you are running (rst.sh). Check the commands in script, you probably need to a systemctl call with sudo.
In php try using this command
exec("/etc/init.d/mysql restart");
or push this command to rst.sh
be ensure have chmod +x on file rst.sh
One of my lines of shell command is not executing despite other similar lines working. I am running on a linux machine using a Ubuntu 12.04 based OS. I have tried using exec as well, still doesn't work.
I actually had this working at some point, where I ran into the hanging issue (waiting for command output), which is why I'm redirecting output to /dev/null. So some where in the development something changed. We did create a debian package to install with and I had run that install package so I thought maybe in overwriting a file the permissions got changed so I added read/write/execute to all users/groups/owners but that didn't work either.
The code is here:
if(isset($_POST['activateXML']))
{
if (videoConsistencyCheck())
{
`cp {$fileXML} /apps/video/xml.xml`;
`sudo /apps/video/vsss restart >/dev/null 2>&1 &`;
systemUnvalidate();
header('Location: index.php?app='.$_GET['app']);
die();
}
}
I know that the first line in the if statement gets executed. The line of code works fine in the actually terminal, so that isn't the problem either. I did lots of Googling and all I could find is an unanswered question, any advice would be helpful.
EDIT: so what appeared to be not working was in fact calling the command as intended but in the bash script I was calling the start-stop daemon was not working
EDIT 2: I made a test php file and ran the code from the terminal, fixed the start-stop-daemon error by adding sudo to the commands but it still doesn't work in my code. I am calling this code when a submit button is pressed.
use additional parameters, especially output:
exec($command,$output);
var_dump($output);
to determine what can be wrong with your command. If it doesn't work, please show us your code where you use your exec's.
The issue lay with a call to a binary file in the vsss script that could only be run as root. We did not want to allow access to that binary file to just anyone. The solution we came up with involves calling chmod +s on the vsss script which allows permissions for user and group IDs but keeps its owner permissions. We then added the PHP user, which was www-data, to the sudoers file using the NOPASSWD parameter. In my PHP code I then used the line:
exec('sudo /apps/video/vsss restart >/dev/null 2>&1 &')
The shell_exec()/backticks would not work with this method.
This is really simple but I cannot get it to work at all. Spent many hours and I've always give up. I created php script called copy.php and it should call a python script called copy.py.
I want to execute a command line like this
<?php exec('/var/www/html/copy.py'); ?>
Really simple.
Why cannot I get the python script executed from php exec()? The function inside python script is to get a copy of error_log from a different directory (outside of Apache) into html directory.
If I run that from a terminal
> php copy.php
It did execute the function and made a copy. Why is that the web browser isn't doing it?
Let me simplify this:
why cannot exec("cp /var/log/httpd/error_log /var/www/html/path/to/php/script") work?
it works fine if I type it in terminal but not when run in a browser.
As others have alluded to, the difference is probably permissions. When you run a command from the command line, you're generally not the same users as your apache script is running as.
Put another way, if from the command line you type whoami, you'll probably get whatever name your user account is.
The echo exec('whoami'); from within php shows who the script is running as, which is Apache.
So, whatever command you're trying to run from your web server isn't available to run as the Apache user. You mentioned you've been able to have exec("python /usr/diskpurge/script.py") work, but not to have exec('/var/www/html/copy.py') doesn't. This is due to in one instance you're running python, in the other you're trying to execute your copy.py script. If copy.py doesn't have execute permissions for the Apache user, you're not going to be able to run it from the browser.
Perhaps different settings apply for the Apache environment versus the command line.
Use error_reporting(E_ALL); and ini_set('display_errors', true) to see what errosr may come up.
It is possible that the Apache environment is prohibited from using exec or the fact that Apache runs under a different user that does not have execute rights on the python script.
sounds like a permission error. Check if your server is running with sufficient rights.
echo exec('whoami');
Set your error reporting to report all:
ini_set('display_errors', true);
error_reporting(E_ALL);
and check for errors..
If your whoami returns a user which is not a member of the SU family (linux) or administration (windows) then resite your permissions..
Linux:
Assign the user returned by whoami correct permissions to run python scripts.. Do not allow the resulted username to run as root with total administration powers.. This is a big no no
The only reason its not working is because you didn't set the write permissions!
Do:
sudo nano /etc/sudoers
And then put the following:
www-data ALL=(root) NOPASSWD:ALL