pam_get_authtok(3) manual page

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 corresponding 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.

`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.

[`PAM_BUF_ERR`]
	Memory buffer error.
[`PAM_CONV_ERR`]
	Conversation failure.
[`PAM_SYSTEM_ERR`]
	System error.
[`PAM_TRY_AGAIN`]
	Try again.

Manual Pages — PAM_GET_AUTHTOK

NAME

CONTENTS

LIBRARY

SYNOPSIS

DESCRIPTION

MODULE OPTIONS

RETURN VALUES

SEE ALSO

STANDARDS

AUTHORS

`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.