1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* Authentication token and access key management internal defs
3 *
4 * Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #ifndef _INTERNAL_H
9 #define _INTERNAL_H
10
11 #include <linux/sched.h>
12 #include <linux/wait_bit.h>
13 #include <linux/cred.h>
14 #include <linux/key-type.h>
15 #include <linux/task_work.h>
16 #include <linux/keyctl.h>
17 #include <linux/refcount.h>
18 #include <linux/watch_queue.h>
19 #include <linux/compat.h>
20 #include <linux/mm.h>
21 #include <linux/vmalloc.h>
22
23 struct iovec;
24
25 #ifdef __KDEBUG
26 #define kenter(FMT, ...) \
27 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
28 #define kleave(FMT, ...) \
29 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
30 #define kdebug(FMT, ...) \
31 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
32 #else
33 #define kenter(FMT, ...) \
34 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
35 #define kleave(FMT, ...) \
36 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
37 #define kdebug(FMT, ...) \
38 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
39 #endif
40
41 extern struct key_type key_type_dead;
42 extern struct key_type key_type_user;
43 extern struct key_type key_type_logon;
44
45 /*****************************************************************************/
46 /*
47 * Keep track of keys for a user.
48 *
49 * This needs to be separate to user_struct to avoid a refcount-loop
50 * (user_struct pins some keyrings which pin this struct).
51 *
52 * We also keep track of keys under request from userspace for this UID here.
53 */
54 struct key_user {
55 struct rb_node node;
56 struct mutex cons_lock; /* construction initiation lock */
57 spinlock_t lock;
58 refcount_t usage; /* for accessing qnkeys & qnbytes */
59 atomic_t nkeys; /* number of keys */
60 atomic_t nikeys; /* number of instantiated keys */
61 kuid_t uid;
62 int qnkeys; /* number of keys allocated to this user */
63 int qnbytes; /* number of bytes allocated to this user */
64 };
65
66 extern struct rb_root key_user_tree;
67 extern spinlock_t key_user_lock;
68 extern struct key_user root_key_user;
69
70 extern struct key_user *key_user_lookup(kuid_t uid);
71 extern void key_user_put(struct key_user *user);
72
73 /*
74 * Key quota limits.
75 * - root has its own separate limits to everyone else
76 */
77 extern unsigned key_quota_root_maxkeys;
78 extern unsigned key_quota_root_maxbytes;
79 extern unsigned key_quota_maxkeys;
80 extern unsigned key_quota_maxbytes;
81
82 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
83
84
85 extern struct kmem_cache *key_jar;
86 extern struct rb_root key_serial_tree;
87 extern spinlock_t key_serial_lock;
88 extern struct mutex key_construction_mutex;
89 extern wait_queue_head_t request_key_conswq;
90
91 extern void key_set_index_key(struct keyring_index_key *index_key);
92 extern struct key_type *key_type_lookup(const char *type);
93 extern void key_type_put(struct key_type *ktype);
94
95 extern int __key_link_lock(struct key *keyring,
96 const struct keyring_index_key *index_key);
97 extern int __key_move_lock(struct key *l_keyring, struct key *u_keyring,
98 const struct keyring_index_key *index_key);
99 extern int __key_link_begin(struct key *keyring,
100 const struct keyring_index_key *index_key,
101 struct assoc_array_edit **_edit);
102 extern int __key_link_check_live_key(struct key *keyring, struct key *key);
103 extern void __key_link(struct key *keyring, struct key *key,
104 struct assoc_array_edit **_edit);
105 extern void __key_link_end(struct key *keyring,
106 const struct keyring_index_key *index_key,
107 struct assoc_array_edit *edit);
108
109 extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
110 const struct keyring_index_key *index_key);
111
112 extern struct key *keyring_search_instkey(struct key *keyring,
113 key_serial_t target_id);
114
115 extern int iterate_over_keyring(const struct key *keyring,
116 int (*func)(const struct key *key, void *data),
117 void *data);
118
119 struct keyring_search_context {
120 struct keyring_index_key index_key;
121 const struct cred *cred;
122 struct key_match_data match_data;
123 unsigned flags;
124 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */
125 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */
126 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */
127 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
128 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
129 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */
130 #define KEYRING_SEARCH_RECURSE 0x0040 /* Search child keyrings also */
131
132 int (*iterator)(const void *object, void *iterator_data);
133
134 /* Internal stuff */
135 int skipped_ret;
136 bool possessed;
137 key_ref_t result;
138 time64_t now;
139 };
140
141 extern bool key_default_cmp(const struct key *key,
142 const struct key_match_data *match_data);
143 extern key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
144 struct keyring_search_context *ctx);
145
146 extern key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx);
147 extern key_ref_t search_process_keyrings_rcu(struct keyring_search_context *ctx);
148
149 extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
150
151 extern int look_up_user_keyrings(struct key **, struct key **);
152 extern struct key *get_user_session_keyring_rcu(const struct cred *);
153 extern int install_thread_keyring_to_cred(struct cred *);
154 extern int install_process_keyring_to_cred(struct cred *);
155 extern int install_session_keyring_to_cred(struct cred *, struct key *);
156
157 extern struct key *request_key_and_link(struct key_type *type,
158 const char *description,
159 struct key_tag *domain_tag,
160 const void *callout_info,
161 size_t callout_len,
162 void *aux,
163 struct key *dest_keyring,
164 unsigned long flags);
165
166 extern bool lookup_user_key_possessed(const struct key *key,
167 const struct key_match_data *match_data);
168
169 extern long join_session_keyring(const char *name);
170 extern void key_change_session_keyring(struct callback_head *twork);
171
172 extern struct work_struct key_gc_work;
173 extern unsigned key_gc_delay;
174 extern void keyring_gc(struct key *keyring, time64_t limit);
175 extern void keyring_restriction_gc(struct key *keyring,
176 struct key_type *dead_type);
177 void key_set_expiry(struct key *key, time64_t expiry);
178 extern void key_schedule_gc(time64_t gc_at);
179 extern void key_schedule_gc_links(void);
180 extern void key_gc_keytype(struct key_type *ktype);
181
182 extern int key_task_permission(const key_ref_t key_ref,
183 const struct cred *cred,
184 enum key_need_perm need_perm);
185
notify_key(struct key * key,enum key_notification_subtype subtype,u32 aux)186 static inline void notify_key(struct key *key,
187 enum key_notification_subtype subtype, u32 aux)
188 {
189 #ifdef CONFIG_KEY_NOTIFICATIONS
190 struct key_notification n = {
191 .watch.type = WATCH_TYPE_KEY_NOTIFY,
192 .watch.subtype = subtype,
193 .watch.info = watch_sizeof(n),
194 .key_id = key_serial(key),
195 .aux = aux,
196 };
197
198 post_watch_notification(key->watchers, &n.watch, current_cred(),
199 n.key_id);
200 #endif
201 }
202
203 /*
204 * Check to see whether permission is granted to use a key in the desired way.
205 */
key_permission(const key_ref_t key_ref,enum key_need_perm need_perm)206 static inline int key_permission(const key_ref_t key_ref,
207 enum key_need_perm need_perm)
208 {
209 return key_task_permission(key_ref, current_cred(), need_perm);
210 }
211
212 extern struct key_type key_type_request_key_auth;
213 extern struct key *request_key_auth_new(struct key *target,
214 const char *op,
215 const void *callout_info,
216 size_t callout_len,
217 struct key *dest_keyring);
218
219 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
220
221 /*
222 * Determine whether a key is dead.
223 */
key_is_dead(const struct key * key,time64_t limit)224 static inline bool key_is_dead(const struct key *key, time64_t limit)
225 {
226 time64_t expiry = key->expiry;
227
228 if (expiry != TIME64_MAX) {
229 if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
230 expiry += key_gc_delay;
231 if (expiry <= limit)
232 return true;
233 }
234
235 return
236 key->flags & ((1 << KEY_FLAG_DEAD) |
237 (1 << KEY_FLAG_INVALIDATED)) ||
238 key->domain_tag->removed;
239 }
240
241 /*
242 * keyctl() functions
243 */
244 extern long keyctl_get_keyring_ID(key_serial_t, int);
245 extern long keyctl_join_session_keyring(const char __user *);
246 extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
247 extern long keyctl_revoke_key(key_serial_t);
248 extern long keyctl_keyring_clear(key_serial_t);
249 extern long keyctl_keyring_link(key_serial_t, key_serial_t);
250 extern long keyctl_keyring_move(key_serial_t, key_serial_t, key_serial_t, unsigned int);
251 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
252 extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
253 extern long keyctl_keyring_search(key_serial_t, const char __user *,
254 const char __user *, key_serial_t);
255 extern long keyctl_read_key(key_serial_t, char __user *, size_t);
256 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
257 extern long keyctl_setperm_key(key_serial_t, key_perm_t);
258 extern long keyctl_instantiate_key(key_serial_t, const void __user *,
259 size_t, key_serial_t);
260 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
261 extern long keyctl_set_reqkey_keyring(int);
262 extern long keyctl_set_timeout(key_serial_t, unsigned);
263 extern long keyctl_assume_authority(key_serial_t);
264 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
265 size_t buflen);
266 extern long keyctl_session_to_parent(void);
267 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
268 extern long keyctl_instantiate_key_iov(key_serial_t,
269 const struct iovec __user *,
270 unsigned, key_serial_t);
271 extern long keyctl_invalidate_key(key_serial_t);
272 extern long keyctl_restrict_keyring(key_serial_t id,
273 const char __user *_type,
274 const char __user *_restriction);
275 #ifdef CONFIG_PERSISTENT_KEYRINGS
276 extern long keyctl_get_persistent(uid_t, key_serial_t);
277 extern unsigned persistent_keyring_expiry;
278 #else
keyctl_get_persistent(uid_t uid,key_serial_t destring)279 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
280 {
281 return -EOPNOTSUPP;
282 }
283 #endif
284
285 #ifdef CONFIG_KEY_DH_OPERATIONS
286 extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
287 size_t, struct keyctl_kdf_params __user *);
288 extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
289 size_t, struct keyctl_kdf_params *);
290 #ifdef CONFIG_COMPAT
291 extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
292 char __user *buffer, size_t buflen,
293 struct compat_keyctl_kdf_params __user *kdf);
294 #endif
295 #define KEYCTL_KDF_MAX_OUTPUT_LEN 1024 /* max length of KDF output */
296 #define KEYCTL_KDF_MAX_OI_LEN 64 /* max length of otherinfo */
297 #else
keyctl_dh_compute(struct keyctl_dh_params __user * params,char __user * buffer,size_t buflen,struct keyctl_kdf_params __user * kdf)298 static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
299 char __user *buffer, size_t buflen,
300 struct keyctl_kdf_params __user *kdf)
301 {
302 return -EOPNOTSUPP;
303 }
304
305 #ifdef CONFIG_COMPAT
compat_keyctl_dh_compute(struct keyctl_dh_params __user * params,char __user * buffer,size_t buflen,struct keyctl_kdf_params __user * kdf)306 static inline long compat_keyctl_dh_compute(
307 struct keyctl_dh_params __user *params,
308 char __user *buffer, size_t buflen,
309 struct keyctl_kdf_params __user *kdf)
310 {
311 return -EOPNOTSUPP;
312 }
313 #endif
314 #endif
315
316 #ifdef CONFIG_ASYMMETRIC_KEY_TYPE
317 extern long keyctl_pkey_query(key_serial_t,
318 const char __user *,
319 struct keyctl_pkey_query __user *);
320
321 extern long keyctl_pkey_verify(const struct keyctl_pkey_params __user *,
322 const char __user *,
323 const void __user *, const void __user *);
324
325 extern long keyctl_pkey_e_d_s(int,
326 const struct keyctl_pkey_params __user *,
327 const char __user *,
328 const void __user *, void __user *);
329 #else
keyctl_pkey_query(key_serial_t id,const char __user * _info,struct keyctl_pkey_query __user * _res)330 static inline long keyctl_pkey_query(key_serial_t id,
331 const char __user *_info,
332 struct keyctl_pkey_query __user *_res)
333 {
334 return -EOPNOTSUPP;
335 }
336
keyctl_pkey_verify(const struct keyctl_pkey_params __user * params,const char __user * _info,const void __user * _in,const void __user * _in2)337 static inline long keyctl_pkey_verify(const struct keyctl_pkey_params __user *params,
338 const char __user *_info,
339 const void __user *_in,
340 const void __user *_in2)
341 {
342 return -EOPNOTSUPP;
343 }
344
keyctl_pkey_e_d_s(int op,const struct keyctl_pkey_params __user * params,const char __user * _info,const void __user * _in,void __user * _out)345 static inline long keyctl_pkey_e_d_s(int op,
346 const struct keyctl_pkey_params __user *params,
347 const char __user *_info,
348 const void __user *_in,
349 void __user *_out)
350 {
351 return -EOPNOTSUPP;
352 }
353 #endif
354
355 extern long keyctl_capabilities(unsigned char __user *_buffer, size_t buflen);
356
357 #ifdef CONFIG_KEY_NOTIFICATIONS
358 extern long keyctl_watch_key(key_serial_t, int, int);
359 #else
keyctl_watch_key(key_serial_t key_id,int watch_fd,int watch_id)360 static inline long keyctl_watch_key(key_serial_t key_id, int watch_fd, int watch_id)
361 {
362 return -EOPNOTSUPP;
363 }
364 #endif
365
366 /*
367 * Debugging key validation
368 */
369 #ifdef KEY_DEBUGGING
370 extern void __key_check(const struct key *);
371
key_check(const struct key * key)372 static inline void key_check(const struct key *key)
373 {
374 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
375 __key_check(key);
376 }
377
378 #else
379
380 #define key_check(key) do {} while(0)
381
382 #endif
383 #endif /* _INTERNAL_H */
384