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