#ifndef CHOOSE_AUTHEN_H
#define CHOOSE_AUTHEN_H 1

#include "tac_plus.h"

#include <sys/types.h>		/* for u_* */


/*
 * This structure describes an authentication method.
 *   authen_name     contains the name of the authentication method.
 *   authen_func     is a pointer to the authentication function.
 *   authen_method   numeric value of authentication method
 */

#define AUTHEN_NAME_SIZE 128

struct authen_data;

struct authen_type {
    char authen_name[AUTHEN_NAME_SIZE];
    int (*authen_func) TAC_ARGS((struct authen_data *data));
    int authen_type;
};

/*
 * The authen_data structure is the data structure for passing
 * information to and from the authentication function
 * (authen_type.authen_func).
 */

struct authen_data {
    struct identity *NAS_id;	/* user identity */
    char *server_msg;		/* null-terminated output msg */

    int server_dlen;		/* output data length */
    unsigned char *server_data;	/* output data */

    char *client_msg;		/* null-terminated input msg a user typed */

    int client_dlen;		/* input data length */
    char *client_data;		/* input data */

    void *method_data;		/* opaque private method data */
    int action;			/* what's to be done */
    int service;		/* calling service */
    int status;			/* Authen status */
    int type;			/* Authen type */
    u_char flags;               /* input & output flags fields */
};

/* return values for  choose_authen(); */

#define CHOOSE_FAILED -1     /* failed to choose an authentication function */
#define CHOOSE_OK      0     /* successfully chose an authentication function */
#define CHOOSE_GETUSER 1     /* need a username before choosing */
#define CHOOSE_BADTYPE 2     /* Invalid preferred authen function specified */


extern int choose_authen TAC_ARGS((struct authen_data *data, struct authen_type *type));


#endif /* CHOOSE_AUTHEN_H */