pam_get_authtok(3) [freebsd man page]

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

PAM_GET_AUTHTOK(3)						 Linux-PAM Manual						PAM_GET_AUTHTOK(3)

NAME

       pam_get_authtok, pam_get_authtok_verify, pam_get_authtok_noverify - get authentication token

SYNOPSIS

       #include <security/pam_ext.h>

       int pam_get_authtok(pam_handle_t *pamh, int item, const char **authtok, const char *prompt);

       int pam_get_authtok_noverify(pam_handle_t *pamh, const char **authtok, const char *prompt);

       int pam_get_authtok_verify(pam_handle_t *pamh, const char **authtok, const char *prompt);

DESCRIPTION

       The pam_get_authtok function returns the cached authentication token, or prompts the user if no token is currently cached. It is intended
       for internal use by Linux-PAM and PAM service modules. Upon successful return, authtok contains a pointer to the value of the
       authentication token. Note, this is a pointer to the actual data and should not be free()'ed or over-written!

       The prompt argument specifies a prompt to use if no token is cached. If a NULL pointer is given, pam_get_authtok uses pre-defined prompts.

       The following values are supported for item:

       PAM_AUTHTOK
	   Returns the current authentication token. Called from pam_sm_chauthtok(3) pam_get_authtok will ask the user to confirm the new token by
	   retyping it. If a prompt was specified, "Retype" will be used as prefix.

       PAM_OLDAUTHTOK
	   Returns the previous authentication token when changing authentication tokens.

       The pam_get_authtok_noverify function can only be used for changing the password (from pam_sm_chauthtok(3)). It returns the cached
       authentication token, or prompts the user if no token is currently cached. The difference to pam_get_authtok is, that this function does
       not ask a second time for the password to verify it. Upon successful return, authtok contains a pointer to the value of the authentication
       token. Note, this is a pointer to the actual data and should not be free()'ed or over-written!

       The pam_get_authtok_verify function can only be used to verify a password for mistypes gotten by pam_get_authtok_noverify(3). This function
       asks a second time for the password and verify it with the password provided by authtok argument. In case of an error, the value of authtok
       is undefined. Else this argument will point to the actual data and should not be free()'ed or over-written!

OPTIONS

       pam_get_authtok honours the following module options:

       try_first_pass
	   Before prompting the user for their password, the module first tries the previous stacked module's password in case that satisfies this
	   module as well.

       use_first_pass
	   The argument use_first_pass forces the module to use a previous stacked modules password and will never prompt the user - if no
	   password is available or the password is not appropriate, the user will be denied access.

       use_authtok
	   When password changing enforce the module to set the new token to the one provided by a previously stacked password module. If no token
	   is available token changing will fail.

       authtok_type=XXX
	   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 option, by default it is empty.

RETURN VALUES

       PAM_AUTH_ERR
	   Authentication token could not be retrieved.

       PAM_AUTHTOK_ERR
	   New authentication could not be retrieved.

       PAM_SUCCESS
	   Authentication token was successfully retrieved.

       PAM_SYSTEM_ERR
	   No space for an authentication token was provided.

       PAM_TRY_AGAIN
	   New authentication tokens mismatch.

SEE ALSO

       pam(8)

STANDARDS

       The pam_get_authtok function is a Linux-PAM extensions.

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