Now we're going to dive a little bit more into the user
password itself and how authentication works.
We can go, of course, and display our password
information, looking for a user account.
We can also then go through and print out the individual fields of our password.
We have an algorithm,
we have the SALT, and then we have the password hash itself.
Now don't worry about them on the screen, as we're going to see this in more
detail from the command line, but we'll break down the purpose of all of this
and look at which elements are encrypted and which elements are clear text.
Passwords themselves are one‑way hashes, they can't be decrypted, so I can't
tell a user what their password is and I can't go through and find out what
their password is. Authentication itself is going to occur because the user
provides the password.
We can combine that password together with the algorithm and the clear
text SALT to be able to see, do we get the same hash coming back? We can
see how this can work by making sure we've got a user set for an existing
user account, going through printing out the information as we saw before,
and then going through and comparing the information using the openssl
command. Again,
we'll run through this from the command line, which we're about
to dive out to now, but hopefully, you're going to find this
really interesting and gain a lot of understanding about
encryption and password management.
So in our next clip, we're going to come back where we start really diving into the complexity of a user password in Linux.