aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/key-ui.h
blob: 159ca8d54e9a9cc349cfe50ff9f2f86a28c16f80 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
/* key-ui.h: key userspace interface stuff for use by keyfs
 *
 * 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_ALL		0x1f	/* 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
 */
static inline int key_permission(const struct key *key, key_perm_t perm)
{
	key_perm_t kperm;

	if (key->uid == current->fsuid)
		kperm = key->perm >> 16;
	else if (key->gid != -1 &&
		 key->perm & KEY_GRP_ALL &&
		 in_group_p(key->gid)
		 )
		kperm = key->perm >> 8;
	else
		kperm = key->perm;

	kperm = kperm & perm & KEY_ALL;

	return kperm == perm;
}

/*
 * check to see whether permission is granted to use a key in at least one of
 * the desired ways
 */
static inline int key_any_permission(const struct key *key, key_perm_t perm)
{
	key_perm_t kperm;

	if (key->uid == current->fsuid)
		kperm = key->perm >> 16;
	else if (key->gid != -1 &&
		 key->perm & KEY_GRP_ALL &&
		 in_group_p(key->gid)
		 )
		kperm = key->perm >> 8;
	else
		kperm = key->perm;

	kperm = kperm & perm & KEY_ALL;

	return kperm != 0;
}


extern struct key *lookup_user_key(key_serial_t id, int create, int part,
				   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 */