1 /* user-type.h: User-defined key type 2 * 3 * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #ifndef _KEYS_USER_TYPE_H 13 #define _KEYS_USER_TYPE_H 14 15 #include <linux/key.h> 16 #include <linux/rcupdate.h> 17 18 #ifdef CONFIG_KEYS 19 20 /*****************************************************************************/ 21 /* 22 * the payload for a key of type "user" or "logon" 23 * - once filled in and attached to a key: 24 * - the payload struct is invariant may not be changed, only replaced 25 * - the payload must be read with RCU procedures or with the key semaphore 26 * held 27 * - the payload may only be replaced with the key semaphore write-locked 28 * - the key's data length is the size of the actual data, not including the 29 * payload wrapper 30 */ 31 struct user_key_payload { 32 struct rcu_head rcu; /* RCU destructor */ 33 unsigned short datalen; /* length of this data */ 34 char data[0]; /* actual data */ 35 }; 36 37 extern struct key_type key_type_user; 38 extern struct key_type key_type_logon; 39 40 struct key_preparsed_payload; 41 42 extern int user_preparse(struct key_preparsed_payload *prep); 43 extern void user_free_preparse(struct key_preparsed_payload *prep); 44 extern int user_update(struct key *key, struct key_preparsed_payload *prep); 45 extern void user_revoke(struct key *key); 46 extern void user_destroy(struct key *key); 47 extern void user_describe(const struct key *user, struct seq_file *m); 48 extern long user_read(const struct key *key, 49 char __user *buffer, size_t buflen); 50 51 static inline const struct user_key_payload *user_key_payload(const struct key *key) 52 { 53 return (struct user_key_payload *)rcu_dereference_key(key); 54 } 55 56 #endif /* CONFIG_KEYS */ 57 58 #endif /* _KEYS_USER_TYPE_H */ 59