| File Permissions and Access Control Lists. |
1.Create a simple file and do ls -ltr to see the details of the files
-> touch permission.txt -> ls -ltr ->-rw-r--r-- o/p--> owner — The owner of the file or application. --> group — The group that owns the file or application --> others — All users with access to the system. (outised the users are in a group)
2.Write an article about File Permissions based on your understanding from the notes.
->File permissions are core to the security model used by Linux systems. They determine who can access files and directories on a system and how
-> rw- The first set of permissions applies to the owner of the file. -> r-- The second set of permissions applies to the user group that owns the file. -> r--The third set of permissions is generally referred to as "others." All Linux files belong to an owner and a group.
->When Linux file permissions are represented by numbers, it's called numeric mode. In numeric mode, a three-digit value represents specific file permissions (for example, 744.) These are called octal values r (read): 4 w (write): 2 x (execute): 1
-> Owner: rwx = 4+2+1 = 7 Group: r-- = 4+0+0 = 4 Others: r-- = 4+0+0 = 4 The results produce the three-digit value 744.
->. You can modify file and directory permissions with the chmod command, which stands for "change mode." To change file permissions in numeric mode, you enter chmod and the octal value you desire, such as 744, alongside the file name.
3.Read about ACL and try out the commands getfacl and setfacl
-> ACL is type of situation is what Linux Access Control Lists (ACLs) were intended to resolve.
ACLs allow us to apply a more specific set of permissions to a file or directory without (necessarily)
changing the base ownership and permissions. They let us "tack on" access for other users or groups.
->setfacl command is used to set or modify the ACL of any file or directory, and getfacl command is used to view the ACL of any file or directory
-getfacl displays the comment header, base ACL (access control list) entries, and extended ACL entries, if there are any, for each file that is specified.
-setfacl sets (replaces), modifies, or removes the access control list (ACL) to regular files and directories. It also updates and deletes ACL entries for each file and directory that was specified by path