PAM_CHAUTHTOK(3PAM) PAM Library Functions PAM_CHAUTHTOK(3PAM)

NAME

pam_chauthtok - perform password related functions within the PAM
framework

SYNOPSIS

cc [ flag ... ] file ... -lpam [ library ... ]
#include <security/pam_appl.h>

int pam_chauthtok(pam_handle_t *pamh, const int flags);

DESCRIPTION

The pam_chauthtok() function is called to change the authentication token
associated with a particular user referenced by the authentication handle
pamh.


The following flag may be passed in to pam_chauthtok():

PAM_SILENT
The password service should not generate
any messages.


PAM_CHANGE_EXPIRED_AUTHTOK
The password service should only update
those passwords that have aged. If this
flag is not passed, all password services
should update their passwords.


PAM_NO_AUTHTOK_CHECK
The password service should not perform
conformance checks on the password entered.


Upon successful completion of the call, the authentication token of the
user will be changed in accordance with the password service configured
in the system through pam.conf(5).

RETURN VALUES

Upon successful completion, PAM_SUCCESS is returned. In addition to the
error return values described in pam(3PAM), the following values may be
returned:

PAM_PERM_DENIED
No permission.


PAM_AUTHTOK_ERR
Authentication token manipulation error.


PAM_AUTHTOK_RECOVERY_ERR
Authentication information cannot be
recovered.


PAM_AUTHTOK_LOCK_BUSY
Authentication token lock busy.


PAM_AUTHTOK_DISABLE_AGING
Authentication token aging disabled.


PAM_USER_UNKNOWN
User unknown to password service.


PAM_TRY_AGAIN
Preliminary check by password service
failed.

ATTRIBUTES

See attributes(7) for description of the following attributes:


+--------------------+-------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------------+
|Interface Stability | Stable |
+--------------------+-------------------------+
|MT-Level | MT-Safe with exceptions |
+--------------------+-------------------------+

SEE ALSO

login(1), passwd(1), pam(3PAM), pam_authenticate(3PAM), pam_start(3PAM),
attributes

NOTES

The flag PAM_CHANGE_EXPIRED_AUTHTOK is typically used by a login
application which has determined that the user's password has aged or
expired. Before allowing the user to login, the login application may
invoke pam_chauthtok() with this flag to allow the user to update the
password. Typically, applications such as passwd(1) should not use this
flag.


The pam_chauthtok() functions performs a preliminary check before
attempting to update passwords. This check is performed for each password
module in the stack as listed in pam.conf(5). The check may include
pinging remote name services to determine if they are available. If
pam_chauthtok() returns PAM_TRY_AGAIN, then the check has failed, and
passwords are not updated.


The flag PAM_NO_AUTHTOK_CHECK is typically used by programs that allow an
administrator to bypass various password conformance checks when setting
a password for a user.


The interfaces in libpam are MT-Safe only if each thread within the
multithreaded application uses its own PAM handle.

March 1, 2005 PAM_CHAUTHTOK(3PAM)