PAM_GET_AUTHTOK(3) BSD Library Functions Manual PAM_GET_AUTHTOK(3)
NAME
pam_get_authtok -- retrieve authentication token
LIBRARY
Pluggable Authentication Module Library (libpam, -lpam)
SYNOPSIS
#include <sys/types.h>
#include <security/pam_appl.h>
int
pam_get_authtok(pam_handle_t *pamh, int item, const char **authtok, const char *prompt);
DESCRIPTION
The pam_get_authtok() function either prompts the user for an authentication token or retrieves a cached authentication token, depending on
circumstances. Either way, a pointer to the authentication token is stored in the location pointed to by the authtok argument, and the cor-
responding PAM item is updated.
The item argument must have one of the following values:
PAM_AUTHTOK Returns the current authentication token, or the new token when changing authentication tokens.
PAM_OLDAUTHTOK Returns the previous authentication token when changing authentication tokens.
The prompt argument specifies a prompt to use if no token is cached. If it is NULL, the PAM_AUTHTOK_PROMPT or PAM_OLDAUTHTOK_PROMPT item, as
appropriate, will be used. If that item is also NULL, a hardcoded default prompt will be used. Additionally, when pam_get_authtok() is
called from a service module, the prompt may be affected by module options as described below. The prompt is then expanded using
openpam_subst(3) before it is passed to the conversation function.
If item is set to PAM_AUTHTOK and there is a non-null PAM_OLDAUTHTOK item, pam_get_authtok() will ask the user to confirm the new token by
retyping it. If there is a mismatch, pam_get_authtok() will return PAM_TRY_AGAIN.
MODULE OPTIONS
When called by a service module, pam_get_authtok() will recognize the following module options:
authtok_prompt Prompt to use when item is set to PAM_AUTHTOK. This option overrides both the prompt argument and the PAM_AUTHTOK_PROMPT
item.
echo_pass If the application's conversation function allows it, this lets the user see what they are typing. This should only be
used for non-reusable authentication tokens.
oldauthtok_prompt Prompt to use when item is set to PAM_OLDAUTHTOK. This option overrides both the prompt argument and the
PAM_OLDAUTHTOK_PROMPT item.
try_first_pass If the requested item is non-null, return it without prompting the user. Typically, the service module will verify the
token, and if it does not match, clear the item before calling pam_get_authtok() a second time.
use_first_pass Do not prompt the user at all; just return the cached value, or PAM_AUTH_ERR if there is none.
RETURN VALUES
The pam_get_authtok() function returns one of the following values:
[PAM_BUF_ERR] Memory buffer error.
[PAM_CONV_ERR] Conversation failure.
[PAM_SYSTEM_ERR] System error.
[PAM_TRY_AGAIN] Try again.
SEE ALSO
openpam_get_option(3), openpam_subst(3), pam(3), pam_conv(3), pam_get_item(3), pam_get_user(3), pam_strerror(3)
STANDARDS
The pam_get_authtok() function is an OpenPAM extension.
AUTHORS
The pam_get_authtok() function and this manual page were developed for the FreeBSD Project by ThinkSec AS and Network Associates Laborato-
ries, the Security Research Division of Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 (``CBOSS''), as part of the
DARPA CHATS research program.
The OpenPAM library is maintained by Dag-Erling Smorgrav <des@des.no>.
BSD
September 12, 2014 BSD
