System Administration Guide: Security Services

Generic pam.conf File

The generic /etc/pam.conf file specifies the following actions:

  1. When the login command is run, authentication must succeed for the pam_authtok_get, pam_dhkeys, pam_auth_unix and the pam_dial_auth modules.

  2. For the rlogin command, authentication through the pam_authtok_get, pam_dhkeys, and pam_auth_unix modules must succeed, if authentication through pam_rhost_auth fails.

  3. The sufficient control flag indicates that for the rlogin command the successful authentication that is provided by the pam_rhost_auth module is sufficient, and the next entry will be ignored.

  4. Most of the other commands that require authentication require successful authentication through the pam_authtok_get, pam_dhkeys, and pam_auth_unix modules.

  5. For the rsh command, authentication through the pam_rhost_auth module is flagged as sufficient. No other authentication is required if authentication through the pam_rhost_auth module succeeds.

The OTHER service name allows a default to be set for any other commands that require authentication that are not included in the file. The OTHER option makes it easier to administer the file, since many commands that are using the same module can be covered by using only one entry. Also, the OTHER service name, when used as a “catch-all,” can ensure that each access is covered by one module. By convention, the OTHER entry is included at the bottom of the section for each module type.

Normally, the entry for the module_path is “root-relative.” If the file name you enter for module_path does not begin with a slash (/), the path /usr/lib/security/$ISA is prepended to the file name. A full path name must be used for modules that are located in other directories. The values for the module_options can be found in the man pages for the module. For example, the UNIX module is covered in the pam_unix(5) man page.


login   auth required           pam_authtok_get.so.1
login   auth required           pam_dhkeys.so.1
login   auth required           pam_unix_auth.so.1
login   auth required           pam_dial_auth.so.1

In this example, the login service specifies authentication through all four authentication modules. A login command fails if any of the modules return an error.