linux-sg2042/include/keys/user-type.h

47 lines
1.6 KiB
C

/* user-type.h: User-defined key type
*
* Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _KEYS_USER_TYPE_H
#define _KEYS_USER_TYPE_H
#include <linux/key.h>
#include <linux/rcupdate.h>
/*****************************************************************************/
/*
* the payload for a key of type "user"
* - once filled in and attached to a key:
* - the payload struct is invariant may not be changed, only replaced
* - the payload must be read with RCU procedures or with the key semaphore
* held
* - the payload may only be replaced with the key semaphore write-locked
* - the key's data length is the size of the actual data, not including the
* payload wrapper
*/
struct user_key_payload {
struct rcu_head rcu; /* RCU destructor */
unsigned short datalen; /* length of this data */
char data[0]; /* actual data */
};
extern struct key_type key_type_user;
extern int user_instantiate(struct key *key, const void *data, size_t datalen);
extern int user_update(struct key *key, const void *data, size_t datalen);
extern int user_match(const struct key *key, const void *criterion);
extern void user_destroy(struct key *key);
extern void user_describe(const struct key *user, struct seq_file *m);
extern long user_read(const struct key *key,
char __user *buffer, size_t buflen);
#endif /* _KEYS_USER_TYPE_H */