kernel-ark/include/linux/key-ui.h
David Howells 29db919063 [PATCH] Keys: Add LSM hooks for key management [try #3]
The attached patch adds LSM hooks for key management facilities. The notable
changes are:

 (1) The key struct now supports a security pointer for the use of security
     modules. This will permit key labelling and restrictions on which
     programs may access a key.

 (2) Security modules get a chance to note (or abort) the allocation of a key.

 (3) The key permission checking can now be enhanced by the security modules;
     the permissions check consults LSM if all other checks bear out.

 (4) The key permissions checking functions now return an error code rather
     than a boolean value.

 (5) An extra permission has been added to govern the modification of
     attributes (UID, GID, permissions).

Note that there isn't an LSM hook specifically for each keyctl() operation,
but rather the permissions hook allows control of individual operations based
on the permission request bits.

Key management access control through LSM is enabled by automatically if both
CONFIG_KEYS and CONFIG_SECURITY are enabled.

This should be applied on top of the patch ensubjected:

	[PATCH] Keys: Possessor permissions should be additive

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Chris Wright <chrisw@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:23 -08:00

67 lines
2.1 KiB
C

/* key-ui.h: key userspace interface stuff
*
* Copyright (C) 2004 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 _LINUX_KEY_UI_H
#define _LINUX_KEY_UI_H
#include <linux/key.h>
/* the key tree */
extern struct rb_root key_serial_tree;
extern spinlock_t key_serial_lock;
/* required permissions */
#define KEY_VIEW 0x01 /* require permission to view attributes */
#define KEY_READ 0x02 /* require permission to read content */
#define KEY_WRITE 0x04 /* require permission to update / modify */
#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
#define KEY_LINK 0x10 /* require permission to link */
#define KEY_SETATTR 0x20 /* require permission to change attributes */
#define KEY_ALL 0x3f /* all the above permissions */
/*
* the keyring payload contains a list of the keys to which the keyring is
* subscribed
*/
struct keyring_list {
struct rcu_head rcu; /* RCU deletion hook */
unsigned short maxkeys; /* max keys this list can hold */
unsigned short nkeys; /* number of keys currently held */
unsigned short delkey; /* key to be unlinked by RCU */
struct key *keys[0];
};
/*
* check to see whether permission is granted to use a key in the desired way
*/
extern int key_task_permission(const key_ref_t key_ref,
struct task_struct *context,
key_perm_t perm);
static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
{
return key_task_permission(key_ref, current, perm);
}
extern key_ref_t lookup_user_key(struct task_struct *context,
key_serial_t id, int create, int partial,
key_perm_t perm);
extern long join_session_keyring(const char *name);
extern struct key_type *key_type_lookup(const char *type);
extern void key_type_put(struct key_type *ktype);
#define key_negative_timeout 60 /* default timeout on a negative key's existence */
#endif /* _LINUX_KEY_UI_H */