22.2.3. Encrypted Passwords

Encrypted passwords are enabled by default because it is more secure. If encrypted passwords are not used, plain text passwords are used, which can be intercepted by someone using a network packet sniffer. It is recommended that encrypted passwords be used.

The Microsoft SMB Protocol originally used plain text passwords. However, Windows NT 4.0 with Service Pack 3 or higher, Windows 98, Windows 2000, Windows ME, and Windows XP require encrypted Samba passwords. To use Samba between a Linux system and a system running one of these Windows operating systems, you can either edit your Windows registry to use plaintext passwords or configure Samba on your Linux system to use encrypted passwords. If you choose to modify your registry, you must do so for all of your Windows machines — this is risky and may cause further conflicts. It is recommended that you use encrypted passwords for better security.

To configure Samba to use encrypted passwords, follow these steps:

The pam_smbpass PAM module can be used to sync users' Samba passwords with their system passwords when the passwd command is used. If a user invokes the passwd command, the password he uses to log in to the Red Hat Enterprise Linux system as well as the password he must provide to connect to a Samba share are changed.

To enable this feature, add the following line to /etc/pam.d/system-auth below the pam_cracklib.so invocation:

password required /lib/security/pam_smbpass.so nullok use_authtok try_first_pass

password required /lib/security/pam_smbpass.so nullok use_authtok try_first_pass