pam_sm_authenticate(3)pam_sm_authenticate(3)NAMEpam_sm_authenticate - Service provider implementation for pam_authenti‐
cate
SYNOPSIS
cc [ flag ... ] file ... -lpam [ library ... ]
#include <security/pam_appl.h>
#include <security/pam_modules.h>
int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const
char **argv);
DESCRIPTION
In response to a call to pam_authenticate(3), the PAM framework calls
pam_sm_authenticate() from the modules listed in the pam.conf(4) file.
The authentication provider supplies the back-end functionality for
this interface function.
The function, pam_sm_authenticate(), is called to verify the identity
of the current user. The user is usually required to enter a password
or similar authentication token depending upon the authentication
scheme configured within the system. The user in question is specified
by a prior call to pam_start(), and is referenced by the authentication
handle, pamh.
The following flag may be passed in to pam_sm_authenticate():
PAM_SILENT The authentication service
should not generate any mes‐
sages
PAM_DISALLOW_NULL_AUTHTOK The authentication service
should return PAM_AUTH_ERROR
if the user has a null
authentication token
The argc argument represents the number of service options passed in
from the configuration file pam.conf(4). argv specifies the service
options, which are interpreted and processed by the authentication ser‐
vice. Please refer to the specific module man pages for the various
available options. If any unknown option is passed in, the module
should log the error and ignore the option.
NOTES
Modules should not retry the authentication in the event of a failure.
Applications should handle authentication retries and maintaining the
retry count. However modules may save the authentication status (suc‐
cess or failure) using the pam_set_data(3) function.
RETURN VALUES
Upon successful completion, PAM_SUCCESS must be returned. In addition,
the following values may be returned:
PAM_MAXTRIES Maximum number of authentication
attempts exceeded
PAM_AUTH_ERR Authentication failure
PAM_CRED_INSUFFICIENT Can not access authentication data
due to insufficient credentials
PAM_AUTHINFO_UNAVAIL Underlying authentication service
can not retrieve authentication
information
PAM_USER_UNKNOWN User not known to underlying
authentication module
PAM_IGNORE Ignore underlying authentication
module regardless of whether the
control flag is required, optional
or sufficient
SEE ALSOpam(3), pam_authenticate(3), pam.conf(4)
19 October 1995 pam_sm_authenticate(3)
