PAM_GET_ITEM(3) 						 Linux-PAM Manual						   PAM_GET_ITEM(3)

NAME

       pam_get_item - getting PAM informations

SYNOPSIS

       #include <security/pam_modules.h>

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

DESCRIPTION

       The pam_get_item function allows applications and PAM service modules to access and retrieve PAM informations of item_type. Upon successful
       return, item contains a pointer to the value of the corresponding item. Note, this is a pointer to the actual data and should not be
       free()'ed or over-written! The following values are supported for item_type:

       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).

       If a service module wishes to obtain the name of the user, it should not use this function, but instead perform a call to pam_get_user(3).

       Only a service module is privileged to read the authentication tokens, PAM_AUTHTOK and PAM_OLDAUTHTOK.

RETURN VALUES

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

       PAM_BUF_ERR
	   Memory buffer error.

       PAM_PERM_DENIED
	   The value of item was NULL.

       PAM_SUCCESS
	   Data was successful updated.

       PAM_SYSTEM_ERR
	   The pam_handle_t passed as first argument was invalid.

SEE ALSO

       pam_set_item(3), pam_strerror(3)

Linux-PAM Manual						    06/04/2011							   PAM_GET_ITEM(3)