Read the Linux Permissions

About this interactive

Linux permissions are simpler than Windows NTFS permissions. Each file or folder has one owner (the user), one group, and everyone else (other), and each of the three gets some mix of read (r), write (w) and execute (x). ls -l shows them as nine characters. The first three are the owner's, the next three the group's, the last three everyone else's. Within each three the order is always r, w, x, and a dash stands in for a permission that is off. So rwxr-x--- means the owner can read, write and execute, the group can read and execute but not write, and everyone else can do nothing. To write a string, build it three characters at a time: owner, then group, then everyone else, filling each with r, w, x or a dash in that order.

What you'll learn

Read a Linux permission string from ls -l: which three characters belong to the owner (user), the group and everyone else, and whether each may read, write or execute
Write the nine permission characters for a stated set of permissions

Aligned to

CompTIA Tech+

3.2 Compare and contrast components of an operating system.

6.4 Compare and contrast authentication, authorization, accounting, and non-repudiation concepts.

CompTIA A+ Core 2

1.11 Identify common features and tools of the Linux client/desktop OS.

Key terms

Linux File Permissions: A permission model in Linux that assigns read, write, and execute rights separately to three categories: the owning user, the owning group, and all others.
Permissions: The defined access rights granted to users, groups, or objects that control what resources they can access or modify.
Access Control: A security mechanism that restricts access to resources based on policies, roles, or identity.

Topics

Linux File Permissions Permissions Access Control Linux Interactive Fill In

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