ch4. Permissions & Ownership

Question 1

ls -l

Answer 1

Bash command to list files and directories in present working directory in descriptive format, including: the permission string, (find the rest)

Question 2

. (in a file system)

Answer 2

self directory

Question 3

.. (in a file system)

Answer 3

parent directory

Question 4

Anatomy of a permission string

Answer 4

11 characters
1st char is ‘d’ for directory or ‘-‘ for file
2nd, 3rd, 4th chars are the owner’s absolute permissions
5th, 6th, 7th chars are the group’s absolute permissions
8th, 9th, 10th chars are the other’s absolute permissions
11th char is SELinux security context +Alternative access methods

Question 5

what command can also be used to modify the permissions of a file or directory?

Answer 5

chmod
-c
-f
-v
-R
(get descriptions for these options)

Question 6

what are symbolic permissions?

Answer 6

way to add or subtract permissions without looking at the absolute value of the permissions (probably expand on this?)

Question 7

what are absolute permissions?

Solve some made up absolute permissions

(advanced) Solve some made up permissions strings

Answer 7

1 = execute
2 = write
3 = write, execute
4 = read
5 = read, execute
6 = read, write
7 = read, write, execute

Question 8

umask
umask -S
umask -p

Answer 8

(I don’t think this is a Bash command. I think this is a programing function that some Bash commands implement, like mkdir)
used to set the default permissions for newly created files and directories
-S umask as a symbolic value
-p umask as an absolute value

Question 9

chown

Answer 9

used to change the owner, group, or both of a file or directory

Question 10

chown syntax

Answer 10

chown [user name] : [group name] [file/directory name]

if you don’t wish to change the owner or the group, just leave the unchanged blank like:
chown [user name] : [file/directory name]
to only change the owner, or
chown : [group name] [file/directory name]
to only change the group name

Question 11

chgrp

Answer 11

Bash command (find) I think to reassign the group of a file or directory

Question 12

ls -ld

Answer 12

Bash command to print the permissions of the current working directory

Question 13

SUID

Answer 13

?

Question 14

SGID

Answer 14

?

Question 15

sticky bit

Answer 15

flags a file so that only an owner of the stick bit’s file or directory or the root user can delete the file

Question 16

attribute set

Answer 16

goes beyond typical permissions to be much more granular

Question 17

immutable flag

Answer 17

prevents modification by even a root user

Question 18

lsattr

Answer 18

Bash command to list the attributes of a file or directory

Question 19

access control list (ACL)

Answer 19

even more granular permission controls

Question 20

getfacl

Answer 20

Bash command to retrieve ACL info of a file or directory

Question 21

setfacl

Answer 21

Bash command to change the permissions of an ACL of a file or directory

Question 22

setfacl -
setfacl -

Question 23

setfacl -r
setfacl -s
setfacl -m
setfacl -x
setfacl -b

Question 24

chattr

Answer 24

Bash command to change the attributes (of a file or directory?)