Merge branch 'master'; commit 'v2.6.38-rc7' into next
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / linux / key.h
CommitLineData
76181c13 1/* Authentication token and access key management
1da177e4 2 *
76181c13 3 * Copyright (C) 2004, 2007 Red Hat, Inc. All Rights Reserved.
1da177e4
LT
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 * See Documentation/keys.txt for information on keys/keyrings.
13 */
14
15#ifndef _LINUX_KEY_H
16#define _LINUX_KEY_H
17
18#include <linux/types.h>
19#include <linux/list.h>
20#include <linux/rbtree.h>
76d8aeab 21#include <linux/rcupdate.h>
0b77f5bf 22#include <linux/sysctl.h>
aa84442d 23#include <linux/rwsem.h>
1da177e4
LT
24#include <asm/atomic.h>
25
26#ifdef __KERNEL__
27
28/* key handle serial number */
29typedef int32_t key_serial_t;
30
31/* key handle permissions mask */
32typedef uint32_t key_perm_t;
33
34struct key;
35
36#ifdef CONFIG_KEYS
37
38#undef KEY_DEBUGGING
39
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DH
40#define KEY_POS_VIEW 0x01000000 /* possessor can view a key's attributes */
41#define KEY_POS_READ 0x02000000 /* possessor can read key payload / view keyring */
42#define KEY_POS_WRITE 0x04000000 /* possessor can update key payload / add link to keyring */
43#define KEY_POS_SEARCH 0x08000000 /* possessor can find a key in search / search a keyring */
44#define KEY_POS_LINK 0x10000000 /* possessor can create a link to a key/keyring */
29db9190
DH
45#define KEY_POS_SETATTR 0x20000000 /* possessor can set key attributes */
46#define KEY_POS_ALL 0x3f000000
664cceb0
DH
47
48#define KEY_USR_VIEW 0x00010000 /* user permissions... */
49#define KEY_USR_READ 0x00020000
50#define KEY_USR_WRITE 0x00040000
51#define KEY_USR_SEARCH 0x00080000
52#define KEY_USR_LINK 0x00100000
29db9190
DH
53#define KEY_USR_SETATTR 0x00200000
54#define KEY_USR_ALL 0x003f0000
1da177e4
LT
55
56#define KEY_GRP_VIEW 0x00000100 /* group permissions... */
57#define KEY_GRP_READ 0x00000200
58#define KEY_GRP_WRITE 0x00000400
59#define KEY_GRP_SEARCH 0x00000800
60#define KEY_GRP_LINK 0x00001000
29db9190
DH
61#define KEY_GRP_SETATTR 0x00002000
62#define KEY_GRP_ALL 0x00003f00
1da177e4
LT
63
64#define KEY_OTH_VIEW 0x00000001 /* third party permissions... */
65#define KEY_OTH_READ 0x00000002
66#define KEY_OTH_WRITE 0x00000004
67#define KEY_OTH_SEARCH 0x00000008
68#define KEY_OTH_LINK 0x00000010
29db9190
DH
69#define KEY_OTH_SETATTR 0x00000020
70#define KEY_OTH_ALL 0x0000003f
1da177e4 71
6b79ccb5
AR
72#define KEY_PERM_UNDEF 0xffffffff
73
1da177e4
LT
74struct seq_file;
75struct user_struct;
76struct signal_struct;
d84f4f99 77struct cred;
1da177e4
LT
78
79struct key_type;
80struct key_owner;
81struct keyring_list;
82struct keyring_name;
83
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DH
84/*****************************************************************************/
85/*
86 * key reference with possession attribute handling
87 *
88 * NOTE! key_ref_t is a typedef'd pointer to a type that is not actually
89 * defined. This is because we abuse the bottom bit of the reference to carry a
90 * flag to indicate whether the calling process possesses that key in one of
91 * its keyrings.
92 *
93 * the key_ref_t has been made a separate type so that the compiler can reject
94 * attempts to dereference it without proper conversion.
95 *
96 * the three functions are used to assemble and disassemble references
97 */
98typedef struct __key_reference_with_attributes *key_ref_t;
99
100static inline key_ref_t make_key_ref(const struct key *key,
101 unsigned long possession)
102{
103 return (key_ref_t) ((unsigned long) key | possession);
104}
105
106static inline struct key *key_ref_to_ptr(const key_ref_t key_ref)
107{
108 return (struct key *) ((unsigned long) key_ref & ~1UL);
109}
110
111static inline unsigned long is_key_possessed(const key_ref_t key_ref)
112{
113 return (unsigned long) key_ref & 1UL;
114}
115
1da177e4
LT
116/*****************************************************************************/
117/*
118 * authentication token / access credential / keyring
119 * - types of key include:
120 * - keyrings
121 * - disk encryption IDs
122 * - Kerberos TGTs and tickets
123 */
124struct key {
125 atomic_t usage; /* number of references */
126 key_serial_t serial; /* key serial number */
127 struct rb_node serial_node;
128 struct key_type *type; /* type of key */
1da177e4
LT
129 struct rw_semaphore sem; /* change vs change sem */
130 struct key_user *user; /* owner of this key */
29db9190 131 void *security; /* security data for this key */
5d135440
DH
132 union {
133 time_t expiry; /* time at which key expires (or 0) */
134 time_t revoked_at; /* time at which key was revoked */
135 };
1da177e4
LT
136 uid_t uid;
137 gid_t gid;
138 key_perm_t perm; /* access permissions */
139 unsigned short quotalen; /* length added to quota */
76d8aeab
DH
140 unsigned short datalen; /* payload data length
141 * - may not match RCU dereferenced payload
142 * - payload should contain own length
143 */
1da177e4
LT
144
145#ifdef KEY_DEBUGGING
146 unsigned magic;
147#define KEY_DEBUG_MAGIC 0x18273645u
148#define KEY_DEBUG_MAGIC_X 0xf8e9dacbu
149#endif
150
76d8aeab
DH
151 unsigned long flags; /* status flags (change with bitops) */
152#define KEY_FLAG_INSTANTIATED 0 /* set if key has been instantiated */
153#define KEY_FLAG_DEAD 1 /* set if key type has been deleted */
154#define KEY_FLAG_REVOKED 2 /* set if key had been revoked */
155#define KEY_FLAG_IN_QUOTA 3 /* set if key consumes quota */
156#define KEY_FLAG_USER_CONSTRUCT 4 /* set if key is being constructed in userspace */
157#define KEY_FLAG_NEGATIVE 5 /* set if key is negative */
158
1da177e4
LT
159 /* the description string
160 * - this is used to match a key against search criteria
161 * - this should be a printable string
162 * - eg: for krb5 AFS, this might be "afs@REDHAT.COM"
163 */
164 char *description;
165
166 /* type specific data
167 * - this is used by the keyring type to index the name
168 */
169 union {
170 struct list_head link;
7318226e
DH
171 unsigned long x[2];
172 void *p[2];
1da177e4
LT
173 } type_data;
174
175 /* key data
176 * - this is used to hold the data actually used in cryptography or
177 * whatever
178 */
179 union {
180 unsigned long value;
e63ba744 181 void __rcu *rcudata;
1da177e4 182 void *data;
e63ba744 183 struct keyring_list __rcu *subscriptions;
1da177e4
LT
184 } payload;
185};
186
1da177e4
LT
187extern struct key *key_alloc(struct key_type *type,
188 const char *desc,
d720024e 189 uid_t uid, gid_t gid,
d84f4f99 190 const struct cred *cred,
7e047ef5
DH
191 key_perm_t perm,
192 unsigned long flags);
193
194
195#define KEY_ALLOC_IN_QUOTA 0x0000 /* add to quota, reject if would overrun */
196#define KEY_ALLOC_QUOTA_OVERRUN 0x0001 /* add to quota, permit even if overrun */
197#define KEY_ALLOC_NOT_IN_QUOTA 0x0002 /* not in quota */
198
1da177e4
LT
199extern void key_revoke(struct key *key);
200extern void key_put(struct key *key);
201
202static inline struct key *key_get(struct key *key)
203{
204 if (key)
205 atomic_inc(&key->usage);
206 return key;
207}
208
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DH
209static inline void key_ref_put(key_ref_t key_ref)
210{
211 key_put(key_ref_to_ptr(key_ref));
212}
213
1da177e4
LT
214extern struct key *request_key(struct key_type *type,
215 const char *description,
216 const char *callout_info);
217
4e54f085
DH
218extern struct key *request_key_with_auxdata(struct key_type *type,
219 const char *description,
4a38e122
DH
220 const void *callout_info,
221 size_t callout_len,
4e54f085
DH
222 void *aux);
223
76181c13
DH
224extern struct key *request_key_async(struct key_type *type,
225 const char *description,
4a38e122
DH
226 const void *callout_info,
227 size_t callout_len);
76181c13
DH
228
229extern struct key *request_key_async_with_auxdata(struct key_type *type,
230 const char *description,
4a38e122
DH
231 const void *callout_info,
232 size_t callout_len,
76181c13
DH
233 void *aux);
234
235extern int wait_for_key_construction(struct key *key, bool intr);
236
1da177e4
LT
237extern int key_validate(struct key *key);
238
664cceb0
DH
239extern key_ref_t key_create_or_update(key_ref_t keyring,
240 const char *type,
241 const char *description,
242 const void *payload,
243 size_t plen,
6b79ccb5 244 key_perm_t perm,
7e047ef5 245 unsigned long flags);
1da177e4 246
664cceb0 247extern int key_update(key_ref_t key,
1da177e4
LT
248 const void *payload,
249 size_t plen);
250
251extern int key_link(struct key *keyring,
252 struct key *key);
253
254extern int key_unlink(struct key *keyring,
255 struct key *key);
256
257extern struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
d84f4f99 258 const struct cred *cred,
7e047ef5 259 unsigned long flags,
d720024e 260 struct key *dest);
1da177e4
LT
261
262extern int keyring_clear(struct key *keyring);
263
664cceb0
DH
264extern key_ref_t keyring_search(key_ref_t keyring,
265 struct key_type *type,
266 const char *description);
1da177e4 267
1da177e4
LT
268extern int keyring_add_key(struct key *keyring,
269 struct key *key);
270
271extern struct key *key_lookup(key_serial_t id);
272
7249db2c
DH
273static inline key_serial_t key_serial(struct key *key)
274{
275 return key ? key->serial : 0;
276}
1da177e4 277
0b77f5bf
DH
278#ifdef CONFIG_SYSCTL
279extern ctl_table key_sysctls[];
280#endif
281
ee18d64c
DH
282extern void key_replace_session_keyring(void);
283
1da177e4
LT
284/*
285 * the userspace interface
286 */
d84f4f99 287extern int install_thread_keyring_to_cred(struct cred *cred);
1da177e4
LT
288extern void key_fsuid_changed(struct task_struct *tsk);
289extern void key_fsgid_changed(struct task_struct *tsk);
290extern void key_init(void);
291
292#else /* CONFIG_KEYS */
293
294#define key_validate(k) 0
295#define key_serial(k) 0
7888e7ff 296#define key_get(k) ({ NULL; })
0dab9cfa 297#define key_revoke(k) do { } while(0)
1da177e4 298#define key_put(k) do { } while(0)
664cceb0 299#define key_ref_put(k) do { } while(0)
8bbf4976
DH
300#define make_key_ref(k, p) NULL
301#define key_ref_to_ptr(k) NULL
664cceb0 302#define is_key_possessed(k) 0
1da177e4
LT
303#define key_fsuid_changed(t) do { } while(0)
304#define key_fsgid_changed(t) do { } while(0)
305#define key_init() do { } while(0)
ee18d64c 306#define key_replace_session_keyring() do { } while(0)
1da177e4
LT
307
308#endif /* CONFIG_KEYS */
309#endif /* __KERNEL__ */
310#endif /* _LINUX_KEY_H */