1 /* Authentication token and access key management internal defs
2 *
3 * Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
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 #ifndef _INTERNAL_H
13 #define _INTERNAL_H
14
15 #include <linux/sched.h>
16 #include <linux/wait_bit.h>
17 #include <linux/cred.h>
18 #include <linux/key-type.h>
19 #include <linux/task_work.h>
20 #include <linux/keyctl.h>
21 #include <linux/refcount.h>
22 #include <linux/compat.h>
23 #include <linux/mm.h>
24 #include <linux/vmalloc.h>
25
26 struct iovec;
27
28 #ifdef __KDEBUG
29 #define kenter(FMT, ...) \
30 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
31 #define kleave(FMT, ...) \
32 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
33 #define kdebug(FMT, ...) \
34 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
35 #else
36 #define kenter(FMT, ...) \
37 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
38 #define kleave(FMT, ...) \
39 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
40 #define kdebug(FMT, ...) \
41 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
42 #endif
43
44 extern struct key_type key_type_dead;
45 extern struct key_type key_type_user;
46 extern struct key_type key_type_logon;
47
48 /*****************************************************************************/
49 /*
50 * Keep track of keys for a user.
51 *
52 * This needs to be separate to user_struct to avoid a refcount-loop
53 * (user_struct pins some keyrings which pin this struct).
54 *
55 * We also keep track of keys under request from userspace for this UID here.
56 */
57 struct key_user {
58 struct rb_node node;
59 struct mutex cons_lock; /* construction initiation lock */
60 spinlock_t lock;
61 refcount_t usage; /* for accessing qnkeys & qnbytes */
62 atomic_t nkeys; /* number of keys */
63 atomic_t nikeys; /* number of instantiated keys */
64 kuid_t uid;
65 int qnkeys; /* number of keys allocated to this user */
66 int qnbytes; /* number of bytes allocated to this user */
67 };
68
69 extern struct rb_root key_user_tree;
70 extern spinlock_t key_user_lock;
71 extern struct key_user root_key_user;
72
73 extern struct key_user *key_user_lookup(kuid_t uid);
74 extern void key_user_put(struct key_user *user);
75
76 /*
77 * Key quota limits.
78 * - root has its own separate limits to everyone else
79 */
80 extern unsigned key_quota_root_maxkeys;
81 extern unsigned key_quota_root_maxbytes;
82 extern unsigned key_quota_maxkeys;
83 extern unsigned key_quota_maxbytes;
84
85 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
86
87
88 extern struct kmem_cache *key_jar;
89 extern struct rb_root key_serial_tree;
90 extern spinlock_t key_serial_lock;
91 extern struct mutex key_construction_mutex;
92 extern wait_queue_head_t request_key_conswq;
93
94
95 extern struct key_type *key_type_lookup(const char *type);
96 extern void key_type_put(struct key_type *ktype);
97
98 extern int __key_link_begin(struct key *keyring,
99 const struct keyring_index_key *index_key,
100 struct assoc_array_edit **_edit);
101 extern int __key_link_check_live_key(struct key *keyring, struct key *key);
102 extern void __key_link(struct key *key, struct assoc_array_edit **_edit);
103 extern void __key_link_end(struct key *keyring,
104 const struct keyring_index_key *index_key,
105 struct assoc_array_edit *edit);
106
107 extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
108 const struct keyring_index_key *index_key);
109
110 extern struct key *keyring_search_instkey(struct key *keyring,
111 key_serial_t target_id);
112
113 extern int iterate_over_keyring(const struct key *keyring,
114 int (*func)(const struct key *key, void *data),
115 void *data);
116
117 struct keyring_search_context {
118 struct keyring_index_key index_key;
119 const struct cred *cred;
120 struct key_match_data match_data;
121 unsigned flags;
122 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */
123 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */
124 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */
125 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
126 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
127 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */
128
129 int (*iterator)(const void *object, void *iterator_data);
130
131 /* Internal stuff */
132 int skipped_ret;
133 bool possessed;
134 key_ref_t result;
135 time64_t now;
136 };
137
138 extern bool key_default_cmp(const struct key *key,
139 const struct key_match_data *match_data);
140 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
141 struct keyring_search_context *ctx);
142
143 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
144 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
145
146 extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
147
148 extern int install_user_keyrings(void);
149 extern int install_thread_keyring_to_cred(struct cred *);
150 extern int install_process_keyring_to_cred(struct cred *);
151 extern int install_session_keyring_to_cred(struct cred *, struct key *);
152
153 extern struct key *request_key_and_link(struct key_type *type,
154 const char *description,
155 const void *callout_info,
156 size_t callout_len,
157 void *aux,
158 struct key *dest_keyring,
159 unsigned long flags);
160
161 extern bool lookup_user_key_possessed(const struct key *key,
162 const struct key_match_data *match_data);
163 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
164 key_perm_t perm);
165 #define KEY_LOOKUP_CREATE 0x01
166 #define KEY_LOOKUP_PARTIAL 0x02
167 #define KEY_LOOKUP_FOR_UNLINK 0x04
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 extern void key_schedule_gc(time64_t gc_at);
178 extern void key_schedule_gc_links(void);
179 extern void key_gc_keytype(struct key_type *ktype);
180
181 extern int key_task_permission(const key_ref_t key_ref,
182 const struct cred *cred,
183 key_perm_t perm);
184
185 /*
186 * Check to see whether permission is granted to use a key in the desired way.
187 */
key_permission(const key_ref_t key_ref,unsigned perm)188 static inline int key_permission(const key_ref_t key_ref, unsigned perm)
189 {
190 return key_task_permission(key_ref, current_cred(), perm);
191 }
192
193 extern struct key_type key_type_request_key_auth;
194 extern struct key *request_key_auth_new(struct key *target,
195 const char *op,
196 const void *callout_info,
197 size_t callout_len,
198 struct key *dest_keyring);
199
200 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
201
202 /*
203 * Determine whether a key is dead.
204 */
key_is_dead(const struct key * key,time64_t limit)205 static inline bool key_is_dead(const struct key *key, time64_t limit)
206 {
207 return
208 key->flags & ((1 << KEY_FLAG_DEAD) |
209 (1 << KEY_FLAG_INVALIDATED)) ||
210 (key->expiry > 0 && key->expiry <= limit);
211 }
212
213 /*
214 * keyctl() functions
215 */
216 extern long keyctl_get_keyring_ID(key_serial_t, int);
217 extern long keyctl_join_session_keyring(const char __user *);
218 extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
219 extern long keyctl_revoke_key(key_serial_t);
220 extern long keyctl_keyring_clear(key_serial_t);
221 extern long keyctl_keyring_link(key_serial_t, key_serial_t);
222 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
223 extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
224 extern long keyctl_keyring_search(key_serial_t, const char __user *,
225 const char __user *, key_serial_t);
226 extern long keyctl_read_key(key_serial_t, char __user *, size_t);
227 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
228 extern long keyctl_setperm_key(key_serial_t, key_perm_t);
229 extern long keyctl_instantiate_key(key_serial_t, const void __user *,
230 size_t, key_serial_t);
231 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
232 extern long keyctl_set_reqkey_keyring(int);
233 extern long keyctl_set_timeout(key_serial_t, unsigned);
234 extern long keyctl_assume_authority(key_serial_t);
235 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
236 size_t buflen);
237 extern long keyctl_session_to_parent(void);
238 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
239 extern long keyctl_instantiate_key_iov(key_serial_t,
240 const struct iovec __user *,
241 unsigned, key_serial_t);
242 extern long keyctl_invalidate_key(key_serial_t);
243
244 struct iov_iter;
245 extern long keyctl_instantiate_key_common(key_serial_t,
246 struct iov_iter *,
247 key_serial_t);
248 extern long keyctl_restrict_keyring(key_serial_t id,
249 const char __user *_type,
250 const char __user *_restriction);
251 #ifdef CONFIG_PERSISTENT_KEYRINGS
252 extern long keyctl_get_persistent(uid_t, key_serial_t);
253 extern unsigned persistent_keyring_expiry;
254 #else
keyctl_get_persistent(uid_t uid,key_serial_t destring)255 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
256 {
257 return -EOPNOTSUPP;
258 }
259 #endif
260
261 #ifdef CONFIG_KEY_DH_OPERATIONS
262 extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
263 size_t, struct keyctl_kdf_params __user *);
264 extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
265 size_t, struct keyctl_kdf_params *);
266 #ifdef CONFIG_KEYS_COMPAT
267 extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
268 char __user *buffer, size_t buflen,
269 struct compat_keyctl_kdf_params __user *kdf);
270 #endif
271 #define KEYCTL_KDF_MAX_OUTPUT_LEN 1024 /* max length of KDF output */
272 #define KEYCTL_KDF_MAX_OI_LEN 64 /* max length of otherinfo */
273 #else
keyctl_dh_compute(struct keyctl_dh_params __user * params,char __user * buffer,size_t buflen,struct keyctl_kdf_params __user * kdf)274 static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
275 char __user *buffer, size_t buflen,
276 struct keyctl_kdf_params __user *kdf)
277 {
278 return -EOPNOTSUPP;
279 }
280
281 #ifdef CONFIG_KEYS_COMPAT
compat_keyctl_dh_compute(struct keyctl_dh_params __user * params,char __user * buffer,size_t buflen,struct keyctl_kdf_params __user * kdf)282 static inline long compat_keyctl_dh_compute(
283 struct keyctl_dh_params __user *params,
284 char __user *buffer, size_t buflen,
285 struct keyctl_kdf_params __user *kdf)
286 {
287 return -EOPNOTSUPP;
288 }
289 #endif
290 #endif
291
292 /*
293 * Debugging key validation
294 */
295 #ifdef KEY_DEBUGGING
296 extern void __key_check(const struct key *);
297
key_check(const struct key * key)298 static inline void key_check(const struct key *key)
299 {
300 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
301 __key_check(key);
302 }
303
304 #else
305
306 #define key_check(key) do {} while(0)
307
308 #endif
309 #endif /* _INTERNAL_H */
310