Tools of the Trade: Quiz 5

There are three types of permissions in Linux that an authorized user can have. What are they?

(a)  

Permissions are granted for three different types of owners. What are the types?

(a)  

drwxrwxrwx

d = ?

r = ?

w = ?

x = ?

how many user types?

(a)  

When the user, the group, and other can all write to a file. This type of file is considered a wo______-writable file. wo______-writable files can pose significant security risks.

(a)  

First, ls -? displays permissions to files and directories. You might also want to display hidden files and identify their permissions. Hidden files, which begin with a period before their name, don't normally appear when you use ls to display file contents. Entering ls -? displays hidden files. Then you can combine these two options to do both. Entering ls -la displays permissions to files and directories, including hidden files.

(a)  

• - rwe rw- r--

• - = ?

• user has all permissions

• group can read and ?

• other can only ?

(a)  

The principle of least priv (a)   is the concept of granting only the minimal access and authorization required to complete a task or function. In other words, users should not have privileges that are beyond what is necessary. Not following the principle of least privilege can create security risks.

The ????? command changes permissions on files and directories.

(a)  

The chmod command requires two arguments. The first argument indicates how to change permissions, and the second argument indicates the file or directory that you want to change permissions for.  For example, the following command would add all permissions to login_sessions.txt:

????? u+rwx,?+???,?+??? login_sessions.txt

If you wanted to take all the permissions away, you could use

???? (a)   login_sessions.txt

Another way to assign these permissions is to use the equals sign (=) in this first argument. Using = with chmod sets, or assigns, the permissions exactly as specified. For example, the following command would set read permissions for login_sessions.txt for user, group, and other:

chmod u=r,?=?,?=? login_sessions.txt

This command overwrites existing permissions. For instance, if the user previously had write permissions, these write permissions are removed after you specify only read permissions with =.

(a)