The
UNIX
authentication service module for PAM,
provides functionality for three PAM categories:
authentication,
account management, and password management.
In terms of the
module-type
parameter, they are the
``auth
''
``account
''
and
``password
''
features.
It also provides a null function for session management.
UNIX
The
UNIX
authentication component
provides functions to verify the identity of a user
(Fn pam_sm_authenticate
)
which obtains the relevant
passwd(5)
entry.
It prompts the user for a password
and verifies that this is correct with
crypt(3).
The following options may be passed to the authentication module:
debug
syslog(3)
debugging information at
LOG_DEBUG
level.
use_first_pass
If the authentication module
is not the first in the stack,
and a previous module
obtained the user's 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 user's password.
try_first_pass
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.
auth_as_self
This option will require the user
to authenticate himself as the user
given by
getlogin(2),
not as the account they are attempting to access.
This is primarily for services like
su(1),
where the user's ability to retype
their own password
might be deemed sufficient.
nullok
If the password database
has no password
for the entity being authenticated,
then this option
will forgo password prompting,
and silently allow authentication to succeed.
local_pass
Use only the local password database,
even if NIS is in use.
This will cause an authentication failure
if the system is configured
to only use NIS.
nis_pass
Use only the NIS password database.
This will cause an authentication failure
if the system is not configured
to use NIS.
UNIX
The
UNIX
account management component
provides a function to perform account management,
pam_sm_acct_mgmt (.);
The function verifies
that the authenticated user
is allowed to log into the local user account
by checking the following criteria:
restrictions on the remote host, login time, and tty.
The following options may be passed to the management module:
debug
syslog(3)
debugging information at
LOG_DEBUG
level.
UNIX
The
UNIX
password management component
provides a function to perform password management,
pam_sm_chauthtok (.);
The function changes
the user's password.
The following options may be passed to the password module:
debug
syslog(3)
debugging information at
LOG_DEBUG
level.
no_warn
suppress warning messages to the user.
These messages include
reasons why the user's
authentication attempt was declined.
local_pass
forces the password module
to change a local password
in favour of a NIS one.
nis_pass
forces the password module
to change a NIS password
in favour of a local one.
