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 key_type *type,
93 const char *description,
94 unsigned long *_prealloc);
95 extern int __key_link_check_live_key(struct key *keyring, struct key *key);
96 extern void __key_link(struct key *keyring, struct key *key,
97 unsigned long *_prealloc);
98 extern void __key_link_end(struct key *keyring,
99 struct key_type *type,
100 unsigned long prealloc);
101
102 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
103 const struct key_type *type,
104 const char *description,
105 key_perm_t perm);
106
107 extern struct key *keyring_search_instkey(struct key *keyring,
108 key_serial_t target_id);
109
110 typedef int (*key_match_func_t)(const struct key *, const void *);
111
112 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
113 const struct cred *cred,
114 struct key_type *type,
115 const void *description,
116 key_match_func_t match,
117 bool no_state_check);
118
119 extern key_ref_t search_my_process_keyrings(struct key_type *type,
120 const void *description,
121 key_match_func_t match,
122 bool no_state_check,
123 const struct cred *cred);
124 extern key_ref_t search_process_keyrings(struct key_type *type,
125 const void *description,
126 key_match_func_t match,
127 const struct cred *cred);
128
129 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
130
131 extern int install_user_keyrings(void);
132 extern int install_thread_keyring_to_cred(struct cred *);
133 extern int install_process_keyring_to_cred(struct cred *);
134 extern int install_session_keyring_to_cred(struct cred *, struct key *);
135
136 extern struct key *request_key_and_link(struct key_type *type,
137 const char *description,
138 const void *callout_info,
139 size_t callout_len,
140 void *aux,
141 struct key *dest_keyring,
142 unsigned long flags);
143
144 extern int lookup_user_key_possessed(const struct key *key, const void *target);
145 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
146 key_perm_t perm);
147 #define KEY_LOOKUP_CREATE 0x01
148 #define KEY_LOOKUP_PARTIAL 0x02
149 #define KEY_LOOKUP_FOR_UNLINK 0x04
150
151 extern long join_session_keyring(const char *name);
152 extern void key_change_session_keyring(struct callback_head *twork);
153
154 extern struct work_struct key_gc_work;
155 extern unsigned key_gc_delay;
156 extern void keyring_gc(struct key *keyring, time_t limit);
157 extern void key_schedule_gc(time_t gc_at);
158 extern void key_schedule_gc_links(void);
159 extern void key_gc_keytype(struct key_type *ktype);
160
161 extern int key_task_permission(const key_ref_t key_ref,
162 const struct cred *cred,
163 key_perm_t perm);
164
165 /*
166 * Check to see whether permission is granted to use a key in the desired way.
167 */
key_permission(const key_ref_t key_ref,key_perm_t perm)168 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
169 {
170 return key_task_permission(key_ref, current_cred(), perm);
171 }
172
173 /* required permissions */
174 #define KEY_VIEW 0x01 /* require permission to view attributes */
175 #define KEY_READ 0x02 /* require permission to read content */
176 #define KEY_WRITE 0x04 /* require permission to update / modify */
177 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
178 #define KEY_LINK 0x10 /* require permission to link */
179 #define KEY_SETATTR 0x20 /* require permission to change attributes */
180 #define KEY_ALL 0x3f /* all the above permissions */
181
182 /*
183 * Authorisation record for request_key().
184 */
185 struct request_key_auth {
186 struct key *target_key;
187 struct key *dest_keyring;
188 const struct cred *cred;
189 void *callout_info;
190 size_t callout_len;
191 pid_t pid;
192 };
193
194 extern struct key_type key_type_request_key_auth;
195 extern struct key *request_key_auth_new(struct key *target,
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(struct key * key,time_t limit)205 static inline bool key_is_dead(struct key *key, time_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 extern long keyctl_instantiate_key_common(key_serial_t,
245 const struct iovec *,
246 unsigned, size_t, key_serial_t);
247
248 /*
249 * Debugging key validation
250 */
251 #ifdef KEY_DEBUGGING
252 extern void __key_check(const struct key *);
253
key_check(const struct key * key)254 static inline void key_check(const struct key *key)
255 {
256 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
257 __key_check(key);
258 }
259
260 #else
261
262 #define key_check(key) do {} while(0)
263
264 #endif
265
266 #endif /* _INTERNAL_H */
267