Permitted values for X are 1 and 2. These indicate the precise time that the filter is to be run. To understand this concept it will be useful to have read the pam(3) manual page. Basically, for each management group there are up to two ways of calling the module's functions. In the case of the authentication and session components there are actually two separate functions. For the case of authentication, these functions are pam_authenticate(3) and pam_setcred(3), here run1 means run the filter from the pam_authenticate function and run2 means run the filter from pam_setcred. In the case of the session modules, run1 implies that the filter is invoked at the pam_open_session(3) stage, and run2 for pam_close_session(3).

For the case of the account component. Either run1 or run2 may be used.

For the case of the password component, run1 is used to indicate that the filter is run on the first occasion of pam_chauthtok(3) (the PAM_PRELIM_CHECK phase) and run2 is used to indicate that the filter is run on the second occasion (the PAM_UPDATE_AUTHTOK phase).

filter

The full pathname of the filter to be run and any command line arguments that the filter might expect.

6.10.3. MODULE TYPES PROVIDED

All module types (auth, account, password and session) are provided.

6.10.4. RETURN VALUES

PAM_SUCCESS

The new filter was set successfully.

PAM_ABORT

Critical error, immediate abort.

6.10.5. EXAMPLES

Add the following line to /etc/pam.d/login to see how to configure login to transpose upper and lower case letters once the user has logged in:

        session required pam_filter.so run1 /lib/security/pam_filter/upperLOWER
      

6.10.6. AUTHOR

pam_filter was written by Andrew G. Morgan <morgan@kernel.org>.