pam_set_item

PAM_SET_ITEM(3)                 Linux-PAM Manual                 PAM_SET_ITEM(3)



NAME
       pam_set_item - set and update PAM information

SYNOPSIS
       #include <security/pam_modules.h>

       int pam_set_item(pam_handle_t *pamh, int item_type, const void *item);

DESCRIPTION
       The pam_set_item function allows applications and PAM service modules to
       access and to update PAM information of item_type. For this a copy of the
       object pointed to by the item argument is created. The following
       item_types are supported:

       PAM_SERVICE
           The service name (which identifies that PAM stack that the PAM
           functions will use to authenticate the program).

       PAM_USER
           The username of the entity under whose identity service will be
           given. That is, following authentication, PAM_USER identifies the
           local entity that gets to use the service. Note, this value can be
           mapped from something (eg., "anonymous") to something else (eg.
           "guest119") by any module in the PAM stack. As such an application
           should consult the value of PAM_USER after each call to a PAM
           function.

       PAM_USER_PROMPT
           The string used when prompting for a user's name. The default value
           for this string is a localized version of "login: ".

       PAM_TTY
           The terminal name: prefixed by /dev/ if it is a device file; for
           graphical, X-based, applications the value for this item should be
           the $DISPLAY variable.

       PAM_RUSER
           The requesting user name: local name for a locally requesting user or
           a remote user name for a remote requesting user.

           Generally an application or module will attempt to supply the value
           that is most strongly authenticated (a local account before a remote
           one. The level of trust in this value is embodied in the actual
           authentication stack associated with the application, so it is
           ultimately at the discretion of the system administrator.

           PAM_RUSER@PAM_RHOST should always identify the requesting user. In
           some cases, PAM_RUSER may be NULL. In such situations, it is unclear
           who the requesting entity is.

       PAM_RHOST
           The requesting hostname (the hostname of the machine from which the
           PAM_RUSER entity is requesting service). That is PAM_RUSER@PAM_RHOST
           does identify the requesting user. In some applications, PAM_RHOST
           may be NULL. In such situations, it is unclear where the
           authentication request is originating from.

       PAM_AUTHTOK
           The authentication token (often a password). This token should be
           ignored by all module functions besides pam_sm_authenticate(3) and
           pam_sm_chauthtok(3). In the former function it is used to pass the
           most recent authentication token from one stacked module to another.
           In the latter function the token is used for another purpose. It
           contains the currently active authentication token.

       PAM_OLDAUTHTOK
           The old authentication token. This token should be ignored by all
           module functions except pam_sm_chauthtok(3).

       PAM_CONV
           The pam_conv structure. See pam_conv(3).

       The following additional items are specific to Linux-PAM and should not
       be used in portable applications:

       PAM_FAIL_DELAY
           A function pointer to redirect centrally managed failure delays. See
           pam_fail_delay(3).

       PAM_XDISPLAY
           The name of the X display. For graphical, X-based applications the
           value for this item should be the $DISPLAY variable. This value may
           be used independently of PAM_TTY for passing the name of the display.

       PAM_XAUTHDATA
           A pointer to a structure containing the X authentication data
           required to make a connection to the display specified by
           PAM_XDISPLAY, if such information is necessary. See
           pam_xauth_data(3).

       PAM_AUTHTOK_TYPE
           The default action is for the module to use the following prompts
           when requesting passwords: "New UNIX password: " and "Retype UNIX
           password: ". The example word UNIX can be replaced with this item, by
           default it is empty. This item is used by pam_get_authtok(3).

       For all item_types, other than PAM_CONV and PAM_FAIL_DELAY, item is a
       pointer to a <NUL> terminated character string. In the case of PAM_CONV,
       item points to an initialized pam_conv structure. In the case of
       PAM_FAIL_DELAY, item is a function pointer: void (*delay_fn)(int retval,
       unsigned usec_delay, void *appdata_ptr)

       Both, PAM_AUTHTOK and PAM_OLDAUTHTOK, will be reset before returning to
       the application. Which means an application is not able to access the
       authentication tokens.

RETURN VALUES
       PAM_BAD_ITEM
           The application attempted to set an undefined or inaccessible item.

       PAM_BUF_ERR
           Memory buffer error.

       PAM_SUCCESS
           Data was successful updated.

       PAM_SYSTEM_ERR
           The pam_handle_t passed as first argument was invalid.

SEE ALSO
       pam_get_item(3), pam_strerror(3)



Linux-PAM Manual                   11/10/2020                    PAM_SET_ITEM(3)