#ifndef PASSDB_H
#define PASSDB_H

#define IS_VALID_PASSWD(pass) \
	((pass)[0] != '\0' && (pass)[0] != '*' && (pass)[0] != '!')

struct auth_request;

enum passdb_result {
	PASSDB_RESULT_INTERNAL_FAILURE = -1,
	PASSDB_RESULT_SCHEME_NOT_AVAILABLE = -2,

	PASSDB_RESULT_USER_UNKNOWN = -3,
	PASSDB_RESULT_USER_DISABLED = -4,
	PASSDB_RESULT_PASS_EXPIRED = -5,

	PASSDB_RESULT_PASSWORD_MISMATCH = 0,
	PASSDB_RESULT_OK = 1
};

typedef void verify_plain_callback_t(enum passdb_result result,
				     struct auth_request *request);
typedef void lookup_credentials_callback_t(enum passdb_result result,
					   const unsigned char *credentials,
					   size_t size,
					   struct auth_request *request);
typedef void set_credentials_callback_t(bool success,
					struct auth_request *request);

struct passdb_module_interface {
	const char *name;

	struct passdb_module *
		(*preinit)(struct auth_passdb *auth_passdb, const char *args);
	void (*init)(struct passdb_module *module, const char *args);
	void (*deinit)(struct passdb_module *module);

	/* Check if plaintext password matches */
	void (*verify_plain)(struct auth_request *request, const char *password,
			     verify_plain_callback_t *callback);

	/* Return authentication credentials, set in
	   auth_request->credentials. */
	void (*lookup_credentials)(struct auth_request *request, 
				   lookup_credentials_callback_t *callback);

	/* Update credentials */
	int (*set_credentials)(struct auth_request *request,
			       const char *new_credentials,
			       set_credentials_callback_t *callback);
};

struct passdb_module {
	/* The caching key for this module, or NULL if caching isn't wanted. */
	const char *cache_key;
	/* Default password scheme for this module.
	   If cache_key is set, must not be NULL. */
	const char *default_pass_scheme;
	/* If blocking is set to TRUE, use child processes to access
	   this passdb. */
	bool blocking;

	struct passdb_module_interface iface;
};

/* Try to get credentials in wanted scheme (request->credentials_scheme) from
   given input. Returns FALSE if this wasn't possible (unknown scheme,
   conversion not possible or invalid credentials).

   If wanted scheme is "", the credentials are returned as-is without any
   checks. This is useful mostly just to see if there exist any credentials
   at all. */
bool passdb_get_credentials(struct auth_request *auth_request,
			    const char *input, const char *input_scheme,
			    const unsigned char **credentials_r,
			    size_t *size_r);

void passdb_handle_credentials(enum passdb_result result,
			       const char *password, const char *scheme,
			       lookup_credentials_callback_t *callback,
                               struct auth_request *auth_request);

struct auth_passdb *passdb_preinit(struct auth *auth, const char *driver,
				   const char *args, unsigned int id);
void passdb_init(struct auth_passdb *passdb);
void passdb_deinit(struct auth_passdb *passdb);

void passdb_register_module(struct passdb_module_interface *iface);
void passdb_unregister_module(struct passdb_module_interface *iface);

void passdbs_init(void);
void passdbs_deinit(void);

#include "auth-request.h"

#endif