Shell Programming and Scripting

----------- Summary -----------
I need a command/set of commands that can help me simulate a shell terminal via a PHP web page using commandline functions. How can I combine the power of nohup and a while loop to:
Is there an easier or better way (SSH being out of the question)?

----------- The Full Story -----------
What I Need To Accomplish
I have a bash script (outsourced) that’s located outside of the web root. I need to access it (and the shell) interactively via HTTPS using PHP’s shell_exec() function. This is to support a big chunk of my clients who use my app on shared hosts and have no SSH access.

Not ideal, I know, but I can’t think of any other option. To mitigate the security risks I’m making this page accessible only to “Super Administrators” (who already have FTP access anyway). I’m also escaping the commands and arguments with escapeshellcmd() and escapeshellarg().

Problem Areas
I have searched Google and this forum for two days. I have gotten some great pointers and tried a few “PHP Terminal Emulators” out there but they are not interactive. They are doing directory traversing via PHP itself and can’t handle confirmation dialogs like “Are you sure you want to continue?”, which requires y/n to be passed back.

I think only PHP would be very limited...

This one uses PHP+Ajax for the interactivity you want xwiterm - eXtreme Web Interactive Terminal - Google Project Hosting.

There are some more, I think, just google for "PHP Ajax terminal emulator"

@teresaejunior Yes, you are right. I didn't mention this but I'm already using AJAX on the script. I skipped mentioning AJAX because the real functionality is coming from the interaction between PHP and the shell. AJAX is only enhancing a user's experience by not refreshing the page.

Thanks for the link to that script. The ones I tried before couldn't handle user interaction. This one says it has "the possibility to execute commands that needs user interaction" so let me try it out and let you know how it goes.

Thanks a lot

I have Webmin installed on my machine, and it has a nice new module called "ajaxterm" and I've just tried it and yes, it supports such interactivity! And does very good! Commands like "read" and "sudo" work perfectly!

http://www.webmin.com/cgi-bin/search...earch=ajaxterm

Both of these scripts sound great but it looks like xwiterm requires root access and ajaxterm requires either root or SSH access Is that the case or I'm wrong?

xwiterm is requiring my "UNIX password". If I try putting in my cPanel password it's (obviously) giving me It's running commands as su. I'm trying to create this script for users with no root or SSH access on a shared host otherwise I would recommend them to use SSH as it's safer and easier that way.

Have you ever tried running ajaxterm separately on a shared host? If you know how to make it run please teach me. Thanks for both of these scripts, I will go over the source code. Maybe I can learn a thing or two from there.

You are going to need root access to install Webmin on the host for ajaxterm. Later you can assign permissions to users to use modules such as ajaxterm, but as you have stated, it could drop the user to SSH. I have tried it both as root and as an Webmin user, and I couldn't notice the difference (if it is /bin/login or SSH)... but in both cases the user is going to need a UNIX password for the shell.

I don't know how safer it would be to use a PHP term instead of SSH, as you can make SSH strong and set iptables rules for dropping people who try to break through the authentication system.

---------- Post updated at 10:40 AM ---------- Previous update was at 10:32 AM ----------

Of course, each user will have its own UNIX password, so only installing and setting permissions would require a root password.

Webmin is bit similar to cPanel, so you know how it works: root has access to all modules, and the other users are limited to what modules you allow them to use.

That confirms my fears. The thing is that the application is not hosted on my server. The users download the application on my website and install it on their own hosting account to have complete control of the application. I need to support users who will be using this application on their shared hosts too.