Copyright (c) 2005, Sun Microsystems, Inc. All Rights Reserved.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
cc [ flag ... ] file ... -lpam [ library ... ] #include <security/pam_appl.h> int pam_authenticate(pam_handle_t *pamh, int flags);
The pam_authenticate() function is called to authenticate the current user. The user is usually required to enter a password or similar authentication token depending upon the authentication service configured within the system. The user in question should have been specified by a prior call to pam_start() or pam_set_item().
The following flags may be set in the flags field: PAM_SILENT
Authentication service should not generate any messages.
The authentication service should return PAM_AUTH_ERR if the user has a null authentication token.
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_AUTH_ERR
Authentication failure.
Cannot access authentication data due to insufficient credentials.
Underlying authentication service cannot retrieve authentication information.
User not known to the underlying authentication module.
An authentication service has maintained a retry count which has been reached. No further retries should be attempted.
See attributes(7) for description of the following attributes:
ATTRIBUTE TYPE ATTRIBUTE VALUE |
Interface Stability Stable |
MT-Level MT-Safe with exceptions |
libpam (3LIB), pam (3PAM), pam_open_session (3PAM), pam_set_item (3PAM), pam_setcred (3PAM), pam_start (3PAM), attributes (7)
In the case of authentication failures due to an incorrect username or password, it is the responsibility of the application to retry pam_authenticate() and to maintain the retry count. An authentication service module may implement an internal retry count and return an error PAM_MAXTRIES if the module does not want the application to retry.
If the PAM framework cannot load the authentication module, then it will return PAM_ABORT. This indicates a serious failure, and the application should not attempt to retry the authentication.
For security reasons, the location of authentication failures is hidden from the user. Thus, if several authentication services are stacked and a single service fails, pam_authenticate() requires that the user re-authenticate each of the services.
A null authentication token in the authentication database will result in successful authentication unless PAM_DISALLOW_NULL_AUTHTOK was specified. In such cases, there will be no prompt to the user to enter an authentication token.
The interfaces in libpam are MT-Safe only if each thread within the multithreaded application uses its own PAM handle.