I am trying to execute Linux shell command from php but there is no output on web page. If I am trying to execute the php page from linux cosole its working fine.
PHP Code:
<?php
$result = shell_exec('asterisk -rx "core show channels concise"');
$ccount =shell_exec('asterisk -rx "core show channels count"');
echo $result;
echo $ccount;
?>
Above code is not giving any output on web page. But on linux console its woking. e.g.
[abc#host sysadminman]# php myfile.php
Asterisk control socket permissions can also be changed easily in /etc/asterisk.conf:
[files]
astctlpermissions = 0660
astctlowner = root
astctlgroup = apache
astctl = asterisk.ctl
First of all your question is incomplete as you not showing what is expected output. But aside from this you are doing a few common mistakes there.
First you are testing your script as root (# php ...) but your httpd is NOT serving your scripts as root. So your tests are useless. You should switch to right user (most likely www-data and then check to run your script from shell. Most likely it will fail for one of two common reasons - insufficient permissions to run asterisk program or incomplete $PATH not pointing to the place where asterisk is.
I agree to Marcin.
I would suggest you write script to execute those commands and put result to some storage (such as text or database). Use cron to run it in root. Then you read the data from storage on web page.
If you want real time response, you have to run cron all the time though it consume server resource. That is trade-off you have to consider. Its depends on what you wanna achieve from the web site.
Use sudo to run thoes commands as root or Asterisk user. You can configure sudo to allow execution without password to only specific commands.
check disable_functions in php.ini. Mb shell_exec just off for web server
Related
$output = shell_exec('echo "php '.$realFile.'" | at '.$targTime.' '.$targDate.' 2>&1');
print $output;
Can someone please help me figure out why the above line isn't doing what it's supposed to be doing? The idea is for it to create an 'at' job that will execute a php script. If I switch to the user apache(which will ideally control the at function when the php file is complete) I can run
echo "php $realFile.php" | at 00:00 05/30/17
and it'll do EXACTLY what I want. The problem is in the above snippet from my php file it will not create the at job correctly. when I do a at -c job# on both of them the job made from my file is about a 3rd the length missing the User info and everything. It basically starts at PATH= and goes down. Doesn't include HOSTNAME=, SHELL=, SSH_CLIENT=, SSH_TTY=, USER=. I assume it needs most of this info to run correctly. The end output (below)is always the same though it just doesn't have any of the top part for some reason. Let me know if you need more info. I didn't want to paste all of my code here as it contains job specific information.
${SHELL:-/bin/sh} << 'marcinDELIMITER0e4bb3e8'
php "$realFile".php
marcinDELIMITER0e4bb3e8
It doesn't seem to be a permission issue because I can su to apache and run the exact command needed. The folder the files are located in are also owned by apache. I've also resulted to giving each file I try to run 777 or 755 permissions through chmod so I don't think that's the issue.
I figured out a coupe ways around it a while back. The way I'm using right now is an ssh2 connect to my own server as root and creating it that way. No compromise as you have to enter the password manually each time. Really bad work around. The main issue is that apache doesn't have the correct permissions to do everything needed for the AT job so someone figuring that out would be awesome. Another option I found on a random webpage would be to use sudo through the php script, but basically the same minus having to reconnect to your own server. Any other options would be appreciated.
Reading the manual and logs would be a good place to start. In particular:
The value of the SHELL environment variable at the time of at invocation will determine which shell is used to execute the at job commands. If SHELL is unset when at is invoked, the user’s login shell will be used; otherwise, if SHELL is set when at is invoked, it must contain the path of a shell interpreter executable that will be used to run the commands at the specified time.
Other things to check are that the user is included in at.allow, SELinux is disabled and the webserver is not running chrrot.
I'm trying execute a python script from php function shell_exec(), but this script require root privileges.
The python code is very simple. Using libraries wifi python does a scan of all the SSID and provides in output the information on the various wireless networks to which he had a scan in JSON format. WiFi libraries are scanning using iwlist that requires root privileges. If it is performed by a user who does not have root privileges, it returns only the information referring to the wifi where you are connected.
If I plug in my code the string
<?php
echo 'Current script owner:'. get_current_user ();
?>
I print screen "Current script owner: root", but if I try to run my code
<?php
$ Output = shell_exec ("python /home/acme/XDOMV2/conn1.py");
echo $ output;
?>
It will only return information about the network on which my debian system is connected.
How to use lighttpd webserver and I have followed several guides about getting to the only result of having to re-install lighttpd.
The question is, is there a way to run a python script as root from lighttpd?
Where am I wrong?
I would suggest to run the script as a user with proper privileages.
This will minimize the risk for exploits on the system.
Next step would be ro run the script in a cron environment as that user (or root in the worst case scenario) and deliver the result via a database or a cached environment. You could also deliver the result via sockets or file handles.
Never enable a web environment to run scripts or well anything as root, it's dangerous and not how the software(lighttpd) were meant to operate.
If you're a brave soul:
This question belongs on UnixExchange but you can check this out:
http://www.sunspot.co.uk/Projects/Joggler/lighttpd_as_root.html
And also check the docs for your lighttpd version, running as root is possible but not sound in any way.
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
i am using arch linux. i want to execute the php file which changes the ip of the system. i did
ifconfig eth0 192.168.163.137
in the terminal and it works fine. the same i tried doing with
shell_exec('ifconfig eth0 192.168.163.137');
in a php file and tried opening the page from a remotely located web browser from another pc connected via router. teh page displays nothing and the code also doesnt execute. i guess its the problem with the user executing it.apache is executing it. so i want it to be run by the root.can anyone please guide me to the execution of my code. i even installed sudo and just put
shell_exec('sudo ifconfig......');
it too doesnt execute...please help...thanku..:)
Sudo normally requires an interactive shell to enter your password. That's obviously not going to happen in a PHP script. If you're sure you know what you're doing and you've got your security issues covered, try allowing the Apache user to run sudo without a password, but only for certain commands.
For example, adding the following line in your sudoers file will allow Apache to run sudo without a password, only for the ifconfig command.
apache ALL=NOPASSWD: /sbin/ifconfig
Adjust the path and add any arguments to suit your needs.
Caution:
There might still be complications due to the way PHP calls shell commands.
Remember that it's very risky to allow the web server to run commands as root!
Probably a better alternative:
Write a shell script with the suid bit to make it run as root no matter who calls it.
shell_exec
This function is disabled when PHP is running in safe mode.
Documentation : http://php.net/manual/en/function.shell-exec.php
So, maybe try tweaking your php.ini file?
Write the commands to a queue and have cron pick them up, validate them (only allow known good requests), and run them, then mark that queue complete with the date and result.
Your end-user can then click/wait for update using ajax.
I'm on a foreign linux system and need to determine the user that apache runs on (and so does php).
The aim:
I need to get the owner of the script (this is no problem as I can use SplFileInfo) and compare it to the owner of the apache process.
I'm open to any alternative proposals.
Regards,
Mario
Edit:
Additional info:
The script is a thumbnail generator, that uses an XML file to generate thumbs from larger images. The script needs to create folders and write files. As I cannot influence the php configuration and I do not have any shell access, this has to be done very silently.
The creation process stopps via exception and sends a mail on failue. As most of php's function cannot throw exceptions on failue, I need some manual checks to determine the environment I'm in. Therefore I need the apache user to compare it to some directory or fileowner.
You can call the php exec function to execute whoami:
<?php echo exec('whoami'); ?>
see posix_getuid() and posix_getpwuid()
Some complicated answers here.
This works for me:
$user = getenv('APACHE_RUN_USER');
Not sure if this is just a new thing that been added to apache since this question was asked but it's definitely there now.
phpinfo will dump a lot of system information. For apache2 installs, there is a section that displays the apache user and group ids. Try creating a php script that just has one line, a call to phpinfo(), and open it in your web browser.
Some php script must be run on apache user (cli), whoami is not appropriate in that case.
Here is my solution :
$output = exec('apachectl -S 2>/dev/null | grep User');
$apacheUser = preg_match('/name="([^"]+)"/', $output, $match) ? $match[1] : 'www-data';