pam_unix2(8)

NAME
pam_unix2 - Standard PAM module for traditional password authentication

DESCRIPTION
The pam_unix2 PAM module is for traditional password authentication. It uses standard calls from the glibc NSS libraries to retrieve and set account information as well as authentication. Usually this is obtained from the the local files /etc/passwd and /etc/shadow or from a NIS map.

The options can be added in the PAM configuration files for every single service. /etc/default/passwd defines, which password encryption algorithm should be used in case of a password change.

If a user matches an entry in /etc/security/uname26.conf and a kernel 3.0 or newer is running, the kernel version number will be changed for this session to 2.6.40. Every line of that config file is an own entry in regexec(3p) format.

OPTIONS
The following options may be passed to all types of management groups except session:

debug
    A lot of debug informations are printed with syslog(3).

nullok
    Normally the account is disabled if no password is set or if the length of the password is zero. With this option the user is allowed to change the password for such accounts. This option does not overwrite a hardcoded default by the calling process.

use_first_pass
    The default is, that pam_unix2 tries to get the authentication token from a previous module. If no token is available, the user is asked for the old password. With this option, pam_unix2 aborts with an error if no authentication token from a previous module is available.

The following additional options may be passed to the passwd rules of this modules:

nisdir=<path>
    This options specifies a path to the source files for NIS maps on a NIS master server. If this option is given, the passwords of NIS accounts will not be changed with yppasswd(1), instead the local passwd and shadow files below <path> will be modified. In conjunction with rpasswdd(8) and pam_make rpc.yppasswdd(8) can be replaced with a more secure solution on the NIS master server.

use_authtok
    Set the new password to the one provided by the previously stacked password module. If this option is not set, pam_unix2 would ask the user for the new password.

One of the following options may be passed to the session rules of this modules:

debug
    Some messages (login time, logout time) are logged to syslog with priority LOG_DEBUG.

trace
    Some messages (login time, logout time) are logged to syslog with priority LOG_NOTICE.

none
    No messages are logged. This is the default.

The acct management does not recognize any additional options. For root, password and login expire are ignored, only on aging warning is printed. If no shadow information exists, it always returns success.

FILES
/etc/default/passwd

SEE ALSO
login(1), passwd(1), pam.conf(5), pam.d(8), pam_pwcheck(8), pam(8), rpasswd(1), rpasswdd(8), rpc.yppasswdd(8), yppasswd(1)