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
23struct 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
41extern struct key_type key_type_dead;
42extern struct key_type key_type_user;
43extern 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 */
54struct 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
66extern struct rb_root key_user_tree;
67extern spinlock_t key_user_lock;
68extern struct key_user root_key_user;
69
70extern struct key_user *key_user_lookup(kuid_t uid);
71extern 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 */
77extern unsigned key_quota_root_maxkeys;
78extern unsigned key_quota_root_maxbytes;
79extern unsigned key_quota_maxkeys;
80extern unsigned key_quota_maxbytes;
81
82#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
83
84
85extern struct kmem_cache *key_jar;
86extern struct rb_root key_serial_tree;
87extern spinlock_t key_serial_lock;
88extern struct mutex key_construction_mutex;
89extern wait_queue_head_t request_key_conswq;
90
91extern void key_set_index_key(struct keyring_index_key *index_key);
92extern struct key_type *key_type_lookup(const char *type);
93extern void key_type_put(struct key_type *ktype);
94
95extern int __key_link_lock(struct key *keyring,
96 const struct keyring_index_key *index_key);
97extern int __key_move_lock(struct key *l_keyring, struct key *u_keyring,
98 const struct keyring_index_key *index_key);
99extern int __key_link_begin(struct key *keyring,
100 const struct keyring_index_key *index_key,
101 struct assoc_array_edit **_edit);
102extern int __key_link_check_live_key(struct key *keyring, struct key *key);
103extern void __key_link(struct key *keyring, struct key *key,
104 struct assoc_array_edit **_edit);
105extern void __key_link_end(struct key *keyring,
106 const struct keyring_index_key *index_key,
107 struct assoc_array_edit *edit);
108
109extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
110 const struct keyring_index_key *index_key);
111
112struct keyring_search_context {
113 struct keyring_index_key index_key;
114 const struct cred *cred;
115 struct key_match_data match_data;
116 unsigned flags;
117#define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */
118#define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */
119#define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */
120#define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
121#define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
122#define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */
123#define KEYRING_SEARCH_RECURSE 0x0040 /* Search child keyrings also */
124
125 int (*iterator)(const void *object, void *iterator_data);
126
127 /* Internal stuff */
128 int skipped_ret;
129 bool possessed;
130 key_ref_t result;
131 time64_t now;
132};
133
134extern bool key_default_cmp(const struct key *key,
135 const struct key_match_data *match_data);
136extern key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
137 struct keyring_search_context *ctx);
138
139extern key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx);
140extern key_ref_t search_process_keyrings_rcu(struct keyring_search_context *ctx);
141
142extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
143
144extern int look_up_user_keyrings(struct key **, struct key **);
145extern struct key *get_user_session_keyring_rcu(const struct cred *);
146extern int install_thread_keyring_to_cred(struct cred *);
147extern int install_process_keyring_to_cred(struct cred *);
148extern int install_session_keyring_to_cred(struct cred *, struct key *);
149
150extern struct key *request_key_and_link(struct key_type *type,
151 const char *description,
152 struct key_tag *domain_tag,
153 const void *callout_info,
154 size_t callout_len,
155 void *aux,
156 struct key *dest_keyring,
157 unsigned long flags);
158
159extern bool lookup_user_key_possessed(const struct key *key,
160 const struct key_match_data *match_data);
161
162extern long join_session_keyring(const char *name);
163extern void key_change_session_keyring(struct callback_head *twork);
164
165extern struct work_struct key_gc_work;
166extern unsigned key_gc_delay;
167extern void keyring_gc(struct key *keyring, time64_t limit);
168extern void keyring_restriction_gc(struct key *keyring,
169 struct key_type *dead_type);
170void key_set_expiry(struct key *key, time64_t expiry);
171extern void key_schedule_gc(time64_t gc_at);
172extern void key_schedule_gc_links(void);
173extern void key_gc_keytype(struct key_type *ktype);
174
175extern int key_task_permission(const key_ref_t key_ref,
176 const struct cred *cred,
177 enum key_need_perm need_perm);
178
179static inline void notify_key(struct key *key,
180 enum key_notification_subtype subtype, u32 aux)
181{
182#ifdef CONFIG_KEY_NOTIFICATIONS
183 struct key_notification n = {
184 .watch.type = WATCH_TYPE_KEY_NOTIFY,
185 .watch.subtype = subtype,
186 .watch.info = watch_sizeof(n),
187 .key_id = key_serial(key),
188 .aux = aux,
189 };
190
191 post_watch_notification(key->watchers, &n.watch, current_cred(),
192 n.key_id);
193#endif
194}
195
196/*
197 * Check to see whether permission is granted to use a key in the desired way.
198 */
199static inline int key_permission(const key_ref_t key_ref,
200 enum key_need_perm need_perm)
201{
202 return key_task_permission(key_ref, current_cred(), need_perm);
203}
204
205extern struct key_type key_type_request_key_auth;
206extern struct key *request_key_auth_new(struct key *target,
207 const char *op,
208 const void *callout_info,
209 size_t callout_len,
210 struct key *dest_keyring);
211
212extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
213
214/*
215 * Determine whether a key is dead.
216 */
217static inline bool key_is_dead(const struct key *key, time64_t limit)
218{
219 time64_t expiry = key->expiry;
220
221 if (expiry != TIME64_MAX) {
222 if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
223 expiry += key_gc_delay;
224 if (expiry <= limit)
225 return true;
226 }
227
228 return
229 key->flags & ((1 << KEY_FLAG_DEAD) |
230 (1 << KEY_FLAG_INVALIDATED)) ||
231 key->domain_tag->removed;
232}
233
234/*
235 * keyctl() functions
236 */
237extern long keyctl_get_keyring_ID(key_serial_t, int);
238extern long keyctl_join_session_keyring(const char __user *);
239extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
240extern long keyctl_revoke_key(key_serial_t);
241extern long keyctl_keyring_clear(key_serial_t);
242extern long keyctl_keyring_link(key_serial_t, key_serial_t);
243extern long keyctl_keyring_move(key_serial_t, key_serial_t, key_serial_t, unsigned int);
244extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
245extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
246extern long keyctl_keyring_search(key_serial_t, const char __user *,
247 const char __user *, key_serial_t);
248extern long keyctl_read_key(key_serial_t, char __user *, size_t);
249extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
250extern long keyctl_setperm_key(key_serial_t, key_perm_t);
251extern long keyctl_instantiate_key(key_serial_t, const void __user *,
252 size_t, key_serial_t);
253extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
254extern long keyctl_set_reqkey_keyring(int);
255extern long keyctl_set_timeout(key_serial_t, unsigned);
256extern long keyctl_assume_authority(key_serial_t);
257extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
258 size_t buflen);
259extern long keyctl_session_to_parent(void);
260extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
261extern long keyctl_instantiate_key_iov(key_serial_t,
262 const struct iovec __user *,
263 unsigned, key_serial_t);
264extern long keyctl_invalidate_key(key_serial_t);
265extern long keyctl_restrict_keyring(key_serial_t id,
266 const char __user *_type,
267 const char __user *_restriction);
268#ifdef CONFIG_PERSISTENT_KEYRINGS
269extern long keyctl_get_persistent(uid_t, key_serial_t);
270extern unsigned persistent_keyring_expiry;
271#else
272static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
273{
274 return -EOPNOTSUPP;
275}
276#endif
277
278#ifdef CONFIG_KEY_DH_OPERATIONS
279extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
280 size_t, struct keyctl_kdf_params __user *);
281extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
282 size_t, struct keyctl_kdf_params *);
283#ifdef CONFIG_COMPAT
284extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
285 char __user *buffer, size_t buflen,
286 struct compat_keyctl_kdf_params __user *kdf);
287#endif
288#define KEYCTL_KDF_MAX_OUTPUT_LEN 1024 /* max length of KDF output */
289#define KEYCTL_KDF_MAX_OI_LEN 64 /* max length of otherinfo */
290#else
291static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
292 char __user *buffer, size_t buflen,
293 struct keyctl_kdf_params __user *kdf)
294{
295 return -EOPNOTSUPP;
296}
297
298#ifdef CONFIG_COMPAT
299static inline long compat_keyctl_dh_compute(
300 struct keyctl_dh_params __user *params,
301 char __user *buffer, size_t buflen,
302 struct keyctl_kdf_params __user *kdf)
303{
304 return -EOPNOTSUPP;
305}
306#endif
307#endif
308
309#ifdef CONFIG_ASYMMETRIC_KEY_TYPE
310extern long keyctl_pkey_query(key_serial_t,
311 const char __user *,
312 struct keyctl_pkey_query __user *);
313
314extern long keyctl_pkey_verify(const struct keyctl_pkey_params __user *,
315 const char __user *,
316 const void __user *, const void __user *);
317
318extern long keyctl_pkey_e_d_s(int,
319 const struct keyctl_pkey_params __user *,
320 const char __user *,
321 const void __user *, void __user *);
322#else
323static inline long keyctl_pkey_query(key_serial_t id,
324 const char __user *_info,
325 struct keyctl_pkey_query __user *_res)
326{
327 return -EOPNOTSUPP;
328}
329
330static inline long keyctl_pkey_verify(const struct keyctl_pkey_params __user *params,
331 const char __user *_info,
332 const void __user *_in,
333 const void __user *_in2)
334{
335 return -EOPNOTSUPP;
336}
337
338static inline long keyctl_pkey_e_d_s(int op,
339 const struct keyctl_pkey_params __user *params,
340 const char __user *_info,
341 const void __user *_in,
342 void __user *_out)
343{
344 return -EOPNOTSUPP;
345}
346#endif
347
348extern long keyctl_capabilities(unsigned char __user *_buffer, size_t buflen);
349
350#ifdef CONFIG_KEY_NOTIFICATIONS
351extern long keyctl_watch_key(key_serial_t, int, int);
352#else
353static inline long keyctl_watch_key(key_serial_t key_id, int watch_fd, int watch_id)
354{
355 return -EOPNOTSUPP;
356}
357#endif
358
359/*
360 * Debugging key validation
361 */
362#ifdef KEY_DEBUGGING
363extern void __key_check(const struct key *);
364
365static inline void key_check(const struct key *key)
366{
367 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
368 __key_check(key);
369}
370
371#else
372
373#define key_check(key) do {} while(0)
374
375#endif
376#endif /* _INTERNAL_H */
377