run commands with root privileges in php with url - php

I have simple PHP code like this:
<?php
print_r(shell_exec($_GET['c']));
now I want to run commands with root privileges through URL.
I have added www-data as sudoers and I try this
curl -vv "http://localhost/index.php?c=echo mypass|sudo -S -s 'whoami'" but I can't see anything in output
This code is just for fun, also I don't want to write my commands in bash script and run them with PHP, I want to know whats wrong with this code

Related

shell_exec() not executing shell script

I've a shell_test.php file in /var/www/html folder with this code:
<?php
shell_exec('/var/www/html/config.sh');
?>
config.sh in the same folder has this code:
#!/bin/sh
sudo -u root kill -SIGHUP $(cat /var/www/html/mosquitto/mosquitto.pid)
When I run ./config.sh from folder, it runs.
When I run command in config.sh file directly in terminal, it
works too.
I've added this into sudoers file so that there is no need of password:
www-data ALL=(ALL) NOPASSWD: /var/www/html/config.sh
The thing is it's working fine when run using terminal in both the mentioned ways. Why is not executing when run in PHP?
Your problem is probably, that it is apache, www-data or some other user that is running your script and you try to run it as root.
Try without sudo -u root and change the group of the file to www-data with:
chown root:www-data your-script
As you say "It isn't outputting anything but my mosquitto broker is resetting every time it runs which lets me know"
I think you should replace
shell_exec('/var/www/html/config.sh');
with
$output = shell_exec('/var/www/html/config.sh');
echo $output;
According to php docs "shell_exec — Execute command via shell and return the complete output as a string"
shell_exec doesn't print by default; you have to store the string output and then use it
I made few changes in codes and it worked.
In shell_test.php, I changed code like this:
<?php
shell_exec('sudo -S ./config.sh');
?>
In config.sh, I changed like this:
#!/bin/sh
sudo kill -SIGHUP $(cat /var/www/html/mosquitto/mosquitto.pid)

Allow PHP/Apache to shell_execute commands on Ubuntu

I'm trying to execute a command through PHP with shell_exec. The PHP file is hosted by Apache on my Ubuntu server.
When I run this:
echo shell_exec("ps ax | grep nginx");
Then I get to see data. But when I run another command, for example:
echo shell_exec("cat /usr/local/nginx/config/nginx.config");
Then it's not showing anything at all. But when I copy that command and paste it in my terminal, then it executes fine.
My Apache server is running as user www-data. So I edited sudoers and added this line:
www-data ALL=(ALL:ALL) ALL
I know this is a security risk, but I wanted to make sure (for now) that www-data is able to execute all commands. But, for some reason I'm still not able to execute all commands with my PHP script.
Anyone any idea what to do?
have you read http://php.net/manual/en/function.shell-exec.php
There is quite a discussion in comments section. Top comment is:
If you're trying to run a command such as "gunzip -t" in shell_exec and getting an empty result, you might need to add 2>&1 to the end of the command, eg:
Won't always work:
echo shell_exec("gunzip -c -t $path_to_backup_file");
Should work:
echo shell_exec("gunzip -c -t $path_to_backup_file 2>&1");
In the above example, a line break at the beginning of the gunzip output seemed to prevent shell_exec printing anything else. Hope this saves someone else an hour or two.
echo shell_exec("sudo cat /usr/local/nginx/config/nginx.config");
Try that.

Can't open gnome-terminal with php

I actually try to laucnh a gnome-term with a php script, seems i have some problems with the users www-data;
my script make only a ls -l command in a directory (is just for a test) and i run it with a php page in my local-web site.
here the gnome-terminal command in my bash script (he run perfectly when i double-click on him) :
gnome-terminal --working-directory=/opt/cuckoo -x bash -c "ls -l"
and here is the call on the php-page :
system("/my/path/to/the/script/script.sh");
i have some echo in my script and i see them in the php page after i try to run the script with the php.page.
i think www-data don't have the right to do so i give the ownership of the script with the chown command, and at last a try the sudo visudo command and make the script execute like the user www-data is root (with NO PASSWD arg)
But i can't open the terminal and make a ls at last, i try with exec too, and show the result with $ouput butthe result is the same as well.
At last my question is : Php can really run a terminal or maybe a fool myself^^? Thanks for taking time to rescure me ;)
PHP can run everything, but depends who spawns it. Forget just running X apps from a web server - you'll need more than just executing them (permissions, DISPLAY and Xauth settings). Read more about the X clients and architecture.
Probably the right place to ask this is at SuperUser, since the problem is not in the coding itself.

Running command-line application from PHP as specific user

I am running Apache on my localhost. From a PHP script run as www-user I would like to control Rhythmbox playback on my machine. So far I have a simple command in my PHP script:
exec('rhythmbox-client --pause');
This works great when I run it from the command-line as me, but if it runs as www-user I guess rhythmbox-client doesn't know/can't access my instance of Rhythmbox.
Is there an easy way for that PHP script to run as my user rather than www-user, or to tell rhythmbox-client which instance to control?
The overall application is that when my phone goes off-hook it calls my PHP script which pauses music, and resumes playback when the phone is on-hook. I love VoIP phones!
Solution:
Thanks to Carpetsmoker and Tarek I used sudo as the answer but there was a couple of problems. To overcome them I did the following:
Created a bash script to call rhythmbox-client. This bash script was executed using sudo in PHP as described in the answer below. Unfortunately rhythmbox-client didn't know what environment to control, so the bash script looks like this:
#! /bin/bash
DBUS_ADDRESS=`grep -z DBUS_SESSION_BUS_ADDRESS /proc/*/environ 2> /dev/null| sed 's/DBUS/\nDBUS/g' | tail -n 1`
if [ "x$DBUS_ADDRESS" != "x" ]; then
export $DBUS_ADDRESS
/usr/bin/rhythmbox-client --pause
fi
Now that bash script can be executed by PHP and wwwuser, and my phone can pause/play my music!
One solution is using sudo(8):
exec('sudo -u myuser ls /');
You will, obviously, need to setup sudo(8) to allow the user running your webserver to invoke it. Editing the sudoers file with visudo(8), you can use something like:
wwwuser ALL=/usr/bin/rhythmbox-client
To prevent Apache from being able to run other commands and only the rythymbox command.
In my case, the solution came this way:
Added this lines to sudoers file:
myuser ALL=(ALL) NOPASSWD: /usr/bin/prlctl
_www ALL=(ALL) NOPASSWD: /usr/bin/prlctl # IMPORTANT!!!
The EXEC() command in PHP was changed to:
exec("sudo -u myuser prlctl list -a", $out, $r);
If a process can be run by any user it can be run by PHP. Example is fortune command
-rwxr-xr-x 1 root root 18816 Oct 1 2009 /usr/games/fortune
Look at the x permission for every user. But this some times doesn't at all work and you may have to let the user, www-data or apache etc, run the program. You can sudo www-data and try to run the command. If it works then Apache/PHP should be able to run it.

what is the best way to run shell script (with root privilege) via php?

I've made a simple bash script for server admininstration and I cannot figure how can I run it in safely inside a php page: I'd like to create a php admininstration page but I obviously don't want to hard-code root password anyware. Let's make an example (this is a foo script, of course)
#!/bin/bash
touch /$1
this simple/stupid script will not work if the user who run it as no writing permission on /.
Actually the script add apache virtualhosts, ftp users and so on...
any ideas?
thanks
Use
sudo /path/to/executable/file
and set up sudo so it can execute the following command for the current user as a root.
http://www.sudo.ws/sudo/sudoers.man.html - here is the sudoers manual, the configuration file, that you have to modify.
zerkms ALL = (ALL) NOPASSWD: /sbin/iptables -L FORWARD -n -v -x
This is example from my /etc/sudoers. Here I allowed to run command /sbin/iptables -L FORWARD -n -v -x as root without asking a password for user zerkms.

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