0

What is the best way to run Linux commands that require "su" with Java? I want it to be very reliable, as for security goes I don't care much about it the system is not a production server. No one ever connects to the machine but myself. I thought about logging in as root so I don't have to deal with the su command and its disabled by default. I'm using Debian 6.

The only thing is that one of my requirements is that the program should start after the normal user logs in without any farther user input. I would set auto login for the normal user and when the computer is turned on and after the normal user logs in I would want that Java program to run as sudo, su without any user input. Would that be possible?

Please tell me a simple and reliable solution.

Regards

Improve this question
13
  • I think you should improve this question a bit more: What do you hope to achieve by doing this? Are you trying to use su (which is really just switch user) to run as a non-root user? Are you trying to run commands as root, and what are you trying to get to as an end goal by using root? If you answer these questions it'll be easier to show you what to do. Commented Jun 21, 2012 at 16:57
  • just throwing this out there for thought: I wonder if you could just use your password in the application when executing the commands somehow - since you said it's for your own use Commented Jun 21, 2012 at 16:58
  • 1
    I would do it a different way. Before you run the program, ensure that whoever is running the program is root (and I think that may be the way it is normally done, not sure). i.e., on startup, make a system call and if the user is not root, exit. Commented Jun 21, 2012 at 17:01
  • 1
    @J-16 SDiZ I think has the right answer. When you're executing one particular command you don't need to do sudo su - root to do that command, you just use sudo. Set up the list of commands in your sudoers file using visudo, set them to run without a password as the user who will run the java program, and then the java program will be able to run those commands. Commented Jun 21, 2012 at 17:34
  • 1
    @VanDarg You can limit what can be used through sudo, it's not really a big problem because you can limit what it does. It's probably a lot worse to run the whole java program as root using gksudo than it is to run a few commands from it as root with no password, as any vulnerabilities in the JVM or in anything the program does automatically become a way to root the machine, whereas if it can just run a limited subset of commands on the system that isn't the case. You don't always want the end user to have that user account's password anyhow to be able to type it in, like at a library kiosk. Commented Jun 21, 2012 at 17:45

2 Answers 2

Reset to default
3

Use sudo instead. It can be configed to allow specific command run without typing in password.

Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

0

For running programs that require root access, they should be run with sudo. The user will be asked to enter a password. As mentioned in the previous answer, sudo can be used to configure commands to be run as root that do not require entering a password. Try looking at the man page for sudo for more information regarding that.

If you want to run programs on system startup, you can write a bash script to run the command gksudo java -jar path when the user logs in. This will prompt the user with a dialog box to enter a password.

I also recommend doing a system call at the beginning of the program to ensure root access.

Improve this answer

Comments

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.