0x01-shell_permissions

0x01. Shell, permissions

In this project, i learnd about all the linux permission.learnd about all the command chmod,sudo,su,chown,chgrp,id,groups,whoami,adduser,useradd and addgroup commands. how change ownership of a file and a dir to a group. changing permission of the the file in a different way.

commands

man or help:

• chmod
• sudo
• su
• chown
• chgrp
• id
• groups
• whoami
• adduser
• useradd
• addgroup

Learning Objectives

Permissions

• What do the commands chmod, sudo, su, chown, chgrp do
• Linux file permissions
• How to represent each of the three sets of permissions (owner, group, and other) as a single digit
• How to change permissions, owner and group of a file
• Why can’t a normal user chown a file
• How to run a command with root privileges
• How to change user ID or become superuser

Other Man Pages

• How to create a user
• How to create a group
• How to print real and effective user and group IDs
• How to print the groups a user is in
• How to print the effective userid

Requirements

General

• Allowed editors: vi, vim, emacs
• All your scripts will be tested on Ubuntu 20.04 LTS
• All your scripts should be exactly two lines long ($ wc -l file should print 2)
• The first line of all your files should be exactly #!/bin/bash
• A README.md file, at the root of the folder of the project, describing what each script is doing
• You are not allowed to use backticks, &&, || or ;
• All your files must be executable

Tasks

0. My name is Betty : A script that switches the current user to the user betty.
1. Who am I : A script that prints the effective username of the current user.
2. Groups : A script that prints all the groups the current user is part of.
3. New owner : A script that changes the owner of the file hello to the user betty.
4. Empty! : A script that creates an empty file called hello.
5. Execute : A script that adds execute permission to the owner of the file hello.
6. Multiple permissions : A script that adds execute permission to the owner and the group owner, and read permission to the other users, to the file hello.
7. Everybody! : A script that adds execution permissions to the owner, the group owner and the other users, to the file hello.
8. James Bond : A script that gives the gives the rest of the users permission and removes all permission for the owner and the group owner.
9. John Doe : A script that sets the mode of the file hello; where owner has all the permissions set, group owner has execute permissions set and others have only write and read permissions set.
10. Look in the mirror : A script that sets the mode of the file hello the same as olleh's mode.
11. Directories : A script that adds execute permission to all subdirectories of the current directory for the owner, the group owner and all other users. (NB: Regular files should not be changed.)
12. More directories : A script that creates a directory called dir_holberton with permissions 751 in the working directory.
13. Change group : A script that changes the group owner to holberton for the file hello.
14. Owner and group : A script that changes the owner to betty and the group owner to holberton for all the files and directories in the working directory.
15. Symbolic links : A script that changes the owner and the group owner of _hello to betty and holberton respectively.
16. If only : A script that changes the owner of the file hello to betty only if it is owned by the user guillaume.
17. Star Wars : A script that will play the StarWars IV episode in the terminal.