pam_sm_authenticate(3)					     Library Functions Manual					    pam_sm_authenticate(3)

NAME

       pam_sm_authenticate - Service provider implementation for pam_authenticate

SYNOPSIS

       [ flag ... ] file ...  [ library ... ]

DESCRIPTION

       In  response to a call to pam_authenticate(3), the PAM framework calls from the modules listed in the pam.conf(4) file.	The authentication
       provider supplies the back-end functionality for this interface function.

       The function, is called to verify the identity of the current user.  The user is usually required to enter a password or similar  authenti-
       cation  token  depending upon the authentication scheme configured within the system.  The user in question is specified by a prior call to
       and is referenced by the authentication handle, pamh.

       If the user is unknown to the authentication service, the service module should mask this error and continue to prompt the user for a pass-
       word.  It should then return the error,

       The following flag may be passed in to

       The authentication service should not generate any messages.

       The authentication service should return
	      if the user has a null authentication token.

       The  argc  argument  represents	the number of module options passed in from the configuration file pam.conf(4).  argv specifies the module
       options, which are interpreted and processed by the authentication service.  Please refer to the specific module manual pages for the vari-
       ous available options.  If any unknown option is passed in, the module should log the error and ignore the option.

       Before  returning, should call and retrieve If it has not been set before (ie. the value is NULL), should set it to the password entered by
       the user using

       An authentication module may save the authentication status (success or reason for failure) as state in	the  authentication  handle  using
       This information is intended for use by

APPLICATION USAGE

       Refer to pam(3) for information on thread-safety of PAM interfaces.

NOTES

       Modules	should	not retry the authentication in the event of a failure.  Applications handle authentication retries and maintain the retry
       count.  To limit the number of retries, the module can return a error.

RETURN VALUES

       Upon successful completion, must be returned.  In addition, the following values may be returned:

       Maximum number of authentication attempts exceeded.

       Authentication failure.

       Can not access authentication data due to insufficient credentials.

       Underlying authentication service can not retrieve authentication information.

       User not known to underlying authentication module.

       Ignore underlying authentication module regardless of whether the control
				    flag is or

SEE ALSO

       pam(3), pam_authenticate(3), pam.conf(4), pam_user.conf(4).

															    pam_sm_authenticate(3)