NAME

       pam_set_item - set and update PAM informations

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
       informations 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 reseted 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)