How to access root packages through php?

Question

Issue: Initially, Through command line as a root user,I accessed a package called pandoc (/root/.cabal/bin/pandoc) which was installed in root folder. When I try to access that package through php using shell_exec(),it fails.

Question: Is there any limitation for php shell_exec() not to access root packages for security purposes? If so,how to resolve it?

I tried: Gave write permission to root folder then I could access root packages through command line not as a root user. yet I couldn't to access it through php shell_exec().

php code:

shell_exec("cd /home/quotequadsco/public_html/pandoc_jats ; sudo -u quotequadsco 
-S /root/.cabal/bin/pandoc ex.tex --filter /root/.cabal/bin/pandoc-citeproc
-t JATS.lua -o ex.xml");

and also tried,

shell_exec("cd /home/quotequadsco/public_html/pandoc_jats ;/root/.cabal/bin/pandoc 
ex.tex --filter /root/.cabal/bin/pandoc-citeproc -t JATS.lua -o ex.xml");

Expectation: I need to execute pandoc root package through shell_exec() in php.

How are you running this script? What user is Apache running under? — Lawrence Cherone, Jan 03 '15 at 09:33
php file in public_html folder running under quotequadsco user — vidhya, Jan 03 '15 at 09:36
Then its not going to work you sure its quotequadsco and not www-data?, you will need to setup apache to run as root, which is unsafe but possible — Lawrence Cherone, Jan 03 '15 at 09:39
http://stackoverflow.com/questions/10915241/how-to-run-from-php-a-bash-script-under-root-user — Lawrence Cherone, Jan 03 '15 at 09:41
I tried the option you suggested in the link but none of them worked — vidhya, Jan 03 '15 at 10:47
I think I have to edit in the sudoers file. Its centOS linux. Can you tell me what are the lines should be added in the sudoers file to run shell_exec as root for specific command? — vidhya, Jan 03 '15 at 12:34

score 0 · Accepted Answer · answered Jan 03 '15 at 13:15

Added the following line in the /etc/sudoer file

#Defaults requiretty   //commented this line
usergroup ALL=(ALL)  ALL

PHP code,

shell_exec("cd /home/quotequadsco/public_html/pandoc_jats ;echo password | sudo 
-S command"); //added a password for sudo command to run as a root user.

score 0 · Answer 2 · answered May 20 '16 at 10:21

I recently published a project that allows PHP to obtain and interact with a real Bash shell (as root if requested), it solves the limitations of exec() and shell_exec(). Get it here: https://github.com/merlinthemagic/MTS

After downloading you would simply use the following code:

$shell    = \MTS\Factories::getDevices()->getLocalHost()->getShell('bash', true);
$return1  = $shell->exeCmd('pandoc (/root/.cabal/bin/pandoc)');
//the return will be a string containing the return of the command
echo $return1;

How to access root packages through php?

2 Answers2