Passwd vs Shadow

[Skybear]

I’m learning about users and groups. The presenter just discussed the Passwd and Shadow commands.

I have two questions:
1) When using Passwd, why do I see only a placeholder (“x”) and not the actual password?
2) Has the use of Passwd changed? When I googled Passwd, the Geeks for Geeks website tells me that command will indeed change a user’s password. https://www.geeksforgeeks.org/linux-unix/passwd-command-in-linux-with-examples/

 

[piorunz]

1. Do you mean password letters are not visible while typing? If yes, it's a simple security feature, stranger will not see your password by looking at your screen from behind your shoulder.
2. Check man passwd in the terminal to read how this command works.

 

[Skybear]

I was getting confused between passwd, to change a password, and cat /etc/passwd, to view user details. I think I understand the difference now. One thing I did use was the man command.

 

[Trml]

Yes, there is also a man shadow, but notice it says "library call" at the top. The passwd command calls the shadow library to encrypt and save the password (in /etc/shadow). This is standard for Linux for a long time and nothing a user needs to worry about. One reason for the change, i.e. not including the password itself in /etc/passwd anymore, was the shadow system can separate and limit access to the passwords:

$ ls -la /etc/passwd /etc/shadow
-rw-r--r--. 1 root root 3063 Dec 16 16:58 /etc/passwd
----------. 1 root root 1409 May 7 08:18 /etc/shadow