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/key-type.h>
17 #include <linux/task_work.h>
18
19 struct iovec;
20
21 #ifdef __KDEBUG
22 #define kenter(FMT, ...) \
23 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
24 #define kleave(FMT, ...) \
25 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
26 #define kdebug(FMT, ...) \
27 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
28 #else
29 #define kenter(FMT, ...) \
30 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
31 #define kleave(FMT, ...) \
32 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
33 #define kdebug(FMT, ...) \
34 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
35 #endif
36
37 extern struct key_type key_type_dead;
38 extern struct key_type key_type_user;
39 extern struct key_type key_type_logon;
40
41 /*****************************************************************************/
42 /*
43 * Keep track of keys for a user.
44 *
45 * This needs to be separate to user_struct to avoid a refcount-loop
46 * (user_struct pins some keyrings which pin this struct).
47 *
48 * We also keep track of keys under request from userspace for this UID here.
49 */
50 struct key_user {
51 struct rb_node node;
52 struct mutex cons_lock; /* construction initiation lock */
53 spinlock_t lock;
54 atomic_t usage; /* for accessing qnkeys & qnbytes */
55 atomic_t nkeys; /* number of keys */
56 atomic_t nikeys; /* number of instantiated keys */
57 kuid_t uid;
58 int qnkeys; /* number of keys allocated to this user */
59 int qnbytes; /* number of bytes allocated to this user */
60 };
61
62 extern struct rb_root key_user_tree;
63 extern spinlock_t key_user_lock;
64 extern struct key_user root_key_user;
65
66 extern struct key_user *key_user_lookup(kuid_t uid);
67 extern void key_user_put(struct key_user *user);
68
69 /*
70 * Key quota limits.
71 * - root has its own separate limits to everyone else
72 */
73 extern unsigned key_quota_root_maxkeys;
74 extern unsigned key_quota_root_maxbytes;
75 extern unsigned key_quota_maxkeys;
76 extern unsigned key_quota_maxbytes;
77
78 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
79
80
81 extern struct kmem_cache *key_jar;
82 extern struct rb_root key_serial_tree;
83 extern spinlock_t key_serial_lock;
84 extern struct mutex key_construction_mutex;
85 extern wait_queue_head_t request_key_conswq;
86
87
88 extern struct key_type *key_type_lookup(const char *type);
89 extern void key_type_put(struct key_type *ktype);
90
91 extern int __key_link_begin(struct key *keyring,
92 const struct keyring_index_key *index_key,
93 struct assoc_array_edit **_edit);
94 extern int __key_link_check_live_key(struct key *keyring, struct key *key);
95 extern void __key_link(struct key *key, struct assoc_array_edit **_edit);
96 extern void __key_link_end(struct key *keyring,
97 const struct keyring_index_key *index_key,
98 struct assoc_array_edit *edit);
99
100 extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
101 const struct keyring_index_key *index_key);
102
103 extern struct key *keyring_search_instkey(struct key *keyring,
104 key_serial_t target_id);
105
106 extern int iterate_over_keyring(const struct key *keyring,
107 int (*func)(const struct key *key, void *data),
108 void *data);
109
110 struct keyring_search_context {
111 struct keyring_index_key index_key;
112 const struct cred *cred;
113 struct key_match_data match_data;
114 unsigned flags;
115 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */
116 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */
117 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */
118 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
119 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
120 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */
121
122 int (*iterator)(const void *object, void *iterator_data);
123
124 /* Internal stuff */
125 int skipped_ret;
126 bool possessed;
127 key_ref_t result;
128 struct timespec now;
129 };
130
131 extern bool key_default_cmp(const struct key *key,
132 const struct key_match_data *match_data);
133 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
134 struct keyring_search_context *ctx);
135
136 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
137 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
138
139 extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
140
141 extern int install_user_keyrings(void);
142 extern int install_thread_keyring_to_cred(struct cred *);
143 extern int install_process_keyring_to_cred(struct cred *);
144 extern int install_session_keyring_to_cred(struct cred *, struct key *);
145
146 extern struct key *request_key_and_link(struct key_type *type,
147 const char *description,
148 const void *callout_info,
149 size_t callout_len,
150 void *aux,
151 struct key *dest_keyring,
152 unsigned long flags);
153
154 extern bool lookup_user_key_possessed(const struct key *key,
155 const struct key_match_data *match_data);
156 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
157 key_perm_t perm);
158 #define KEY_LOOKUP_CREATE 0x01
159 #define KEY_LOOKUP_PARTIAL 0x02
160 #define KEY_LOOKUP_FOR_UNLINK 0x04
161
162 extern long join_session_keyring(const char *name);
163 extern void key_change_session_keyring(struct callback_head *twork);
164
165 extern struct work_struct key_gc_work;
166 extern unsigned key_gc_delay;
167 extern void keyring_gc(struct key *keyring, time_t limit);
168 extern void key_schedule_gc(time_t gc_at);
169 extern void key_schedule_gc_links(void);
170 extern void key_gc_keytype(struct key_type *ktype);
171
172 extern int key_task_permission(const key_ref_t key_ref,
173 const struct cred *cred,
174 key_perm_t perm);
175
176 /*
177 * Check to see whether permission is granted to use a key in the desired way.
178 */
key_permission(const key_ref_t key_ref,unsigned perm)179 static inline int key_permission(const key_ref_t key_ref, unsigned perm)
180 {
181 return key_task_permission(key_ref, current_cred(), perm);
182 }
183
184 /*
185 * Authorisation record for request_key().
186 */
187 struct request_key_auth {
188 struct key *target_key;
189 struct key *dest_keyring;
190 const struct cred *cred;
191 void *callout_info;
192 size_t callout_len;
193 pid_t pid;
194 };
195
196 extern struct key_type key_type_request_key_auth;
197 extern struct key *request_key_auth_new(struct key *target,
198 const void *callout_info,
199 size_t callout_len,
200 struct key *dest_keyring);
201
202 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
203
204 /*
205 * Determine whether a key is dead.
206 */
key_is_dead(const struct key * key,time_t limit)207 static inline bool key_is_dead(const struct key *key, time_t limit)
208 {
209 return
210 key->flags & ((1 << KEY_FLAG_DEAD) |
211 (1 << KEY_FLAG_INVALIDATED)) ||
212 (key->expiry > 0 && key->expiry <= limit);
213 }
214
215 /*
216 * keyctl() functions
217 */
218 extern long keyctl_get_keyring_ID(key_serial_t, int);
219 extern long keyctl_join_session_keyring(const char __user *);
220 extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
221 extern long keyctl_revoke_key(key_serial_t);
222 extern long keyctl_keyring_clear(key_serial_t);
223 extern long keyctl_keyring_link(key_serial_t, key_serial_t);
224 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
225 extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
226 extern long keyctl_keyring_search(key_serial_t, const char __user *,
227 const char __user *, key_serial_t);
228 extern long keyctl_read_key(key_serial_t, char __user *, size_t);
229 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
230 extern long keyctl_setperm_key(key_serial_t, key_perm_t);
231 extern long keyctl_instantiate_key(key_serial_t, const void __user *,
232 size_t, key_serial_t);
233 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
234 extern long keyctl_set_reqkey_keyring(int);
235 extern long keyctl_set_timeout(key_serial_t, unsigned);
236 extern long keyctl_assume_authority(key_serial_t);
237 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
238 size_t buflen);
239 extern long keyctl_session_to_parent(void);
240 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
241 extern long keyctl_instantiate_key_iov(key_serial_t,
242 const struct iovec __user *,
243 unsigned, key_serial_t);
244 extern long keyctl_invalidate_key(key_serial_t);
245
246 struct iov_iter;
247 extern long keyctl_instantiate_key_common(key_serial_t,
248 struct iov_iter *,
249 key_serial_t);
250 #ifdef CONFIG_PERSISTENT_KEYRINGS
251 extern long keyctl_get_persistent(uid_t, key_serial_t);
252 extern unsigned persistent_keyring_expiry;
253 #else
keyctl_get_persistent(uid_t uid,key_serial_t destring)254 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
255 {
256 return -EOPNOTSUPP;
257 }
258 #endif
259
260 /*
261 * Debugging key validation
262 */
263 #ifdef KEY_DEBUGGING
264 extern void __key_check(const struct key *);
265
key_check(const struct key * key)266 static inline void key_check(const struct key *key)
267 {
268 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
269 __key_check(key);
270 }
271
272 #else
273
274 #define key_check(key) do {} while(0)
275
276 #endif
277
278 #endif /* _INTERNAL_H */
279