The user is prompted for a password if necessary. Authorization is performed by comparing the Kerberos 5 principal with those listed in the .k5login file in the target accounts home directory (e.g. /root/.k5login for root).
The following options may be passed to the authentication module:
syslog(3) debugging information at LOG_DEBUG level.
If the authentication module is not the first in the stack, and a previous module obtained the users password, that password is used to authenticate the user. If this fails, the authentication module returns failure without prompting the user for a password. This option has no effect if the authentication module is the first in the stack, or if no previous modules obtained the users password.
This option is similar to the use_first_pass option, except that if the previously obtained password fails, the user is prompted for another password.