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
18 #ifdef __KDEBUG
19 #define kenter(FMT, ...) \
20 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
21 #define kleave(FMT, ...) \
22 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
23 #define kdebug(FMT, ...) \
24 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
25 #else
26 #define kenter(FMT, ...) \
27 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
28 #define kleave(FMT, ...) \
29 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
30 #define kdebug(FMT, ...) \
31 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
32 #endif
33
34 extern struct key_type key_type_dead;
35 extern struct key_type key_type_user;
36 extern struct key_type key_type_logon;
37
38 /*****************************************************************************/
39 /*
40 * Keep track of keys for a user.
41 *
42 * This needs to be separate to user_struct to avoid a refcount-loop
43 * (user_struct pins some keyrings which pin this struct).
44 *
45 * We also keep track of keys under request from userspace for this UID here.
46 */
47 struct key_user {
48 struct rb_node node;
49 struct mutex cons_lock; /* construction initiation lock */
50 spinlock_t lock;
51 atomic_t usage; /* for accessing qnkeys & qnbytes */
52 atomic_t nkeys; /* number of keys */
53 atomic_t nikeys; /* number of instantiated keys */
54 uid_t uid;
55 struct user_namespace *user_ns;
56 int qnkeys; /* number of keys allocated to this user */
57 int qnbytes; /* number of bytes allocated to this user */
58 };
59
60 extern struct rb_root key_user_tree;
61 extern spinlock_t key_user_lock;
62 extern struct key_user root_key_user;
63
64 extern struct key_user *key_user_lookup(uid_t uid,
65 struct user_namespace *user_ns);
66 extern void key_user_put(struct key_user *user);
67
68 /*
69 * Key quota limits.
70 * - root has its own separate limits to everyone else
71 */
72 extern unsigned key_quota_root_maxkeys;
73 extern unsigned key_quota_root_maxbytes;
74 extern unsigned key_quota_maxkeys;
75 extern unsigned key_quota_maxbytes;
76
77 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
78
79
80 extern struct kmem_cache *key_jar;
81 extern struct rb_root key_serial_tree;
82 extern spinlock_t key_serial_lock;
83 extern struct mutex key_construction_mutex;
84 extern wait_queue_head_t request_key_conswq;
85
86
87 extern struct key_type *key_type_lookup(const char *type);
88 extern void key_type_put(struct key_type *ktype);
89
90 extern int __key_link_begin(struct key *keyring,
91 const struct key_type *type,
92 const char *description,
93 unsigned long *_prealloc);
94 extern int __key_link_check_live_key(struct key *keyring, struct key *key);
95 extern void __key_link(struct key *keyring, struct key *key,
96 unsigned long *_prealloc);
97 extern void __key_link_end(struct key *keyring,
98 struct key_type *type,
99 unsigned long prealloc);
100
101 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
102 const struct key_type *type,
103 const char *description,
104 key_perm_t perm);
105
106 extern struct key *keyring_search_instkey(struct key *keyring,
107 key_serial_t target_id);
108
109 typedef int (*key_match_func_t)(const struct key *, const void *);
110
111 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
112 const struct cred *cred,
113 struct key_type *type,
114 const void *description,
115 key_match_func_t match,
116 bool no_state_check);
117
118 extern key_ref_t search_my_process_keyrings(struct key_type *type,
119 const void *description,
120 key_match_func_t match,
121 bool no_state_check,
122 const struct cred *cred);
123 extern key_ref_t search_process_keyrings(struct key_type *type,
124 const void *description,
125 key_match_func_t match,
126 const struct cred *cred);
127
128 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
129
130 extern int install_user_keyrings(void);
131 extern int install_thread_keyring_to_cred(struct cred *);
132 extern int install_process_keyring_to_cred(struct cred *);
133 extern int install_session_keyring_to_cred(struct cred *, struct key *);
134
135 extern struct key *request_key_and_link(struct key_type *type,
136 const char *description,
137 const void *callout_info,
138 size_t callout_len,
139 void *aux,
140 struct key *dest_keyring,
141 unsigned long flags);
142
143 extern int lookup_user_key_possessed(const struct key *key, const void *target);
144 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
145 key_perm_t perm);
146 #define KEY_LOOKUP_CREATE 0x01
147 #define KEY_LOOKUP_PARTIAL 0x02
148 #define KEY_LOOKUP_FOR_UNLINK 0x04
149
150 extern long join_session_keyring(const char *name);
151
152 extern struct work_struct key_gc_work;
153 extern unsigned key_gc_delay;
154 extern void keyring_gc(struct key *keyring, time_t limit);
155 extern void key_schedule_gc(time_t expiry_at);
156 extern void key_gc_keytype(struct key_type *ktype);
157
158 extern int key_task_permission(const key_ref_t key_ref,
159 const struct cred *cred,
160 key_perm_t perm);
161
162 /*
163 * Check to see whether permission is granted to use a key in the desired way.
164 */
key_permission(const key_ref_t key_ref,key_perm_t perm)165 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
166 {
167 return key_task_permission(key_ref, current_cred(), perm);
168 }
169
170 /* required permissions */
171 #define KEY_VIEW 0x01 /* require permission to view attributes */
172 #define KEY_READ 0x02 /* require permission to read content */
173 #define KEY_WRITE 0x04 /* require permission to update / modify */
174 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
175 #define KEY_LINK 0x10 /* require permission to link */
176 #define KEY_SETATTR 0x20 /* require permission to change attributes */
177 #define KEY_ALL 0x3f /* all the above permissions */
178
179 /*
180 * Authorisation record for request_key().
181 */
182 struct request_key_auth {
183 struct key *target_key;
184 struct key *dest_keyring;
185 const struct cred *cred;
186 void *callout_info;
187 size_t callout_len;
188 pid_t pid;
189 };
190
191 extern struct key_type key_type_request_key_auth;
192 extern struct key *request_key_auth_new(struct key *target,
193 const void *callout_info,
194 size_t callout_len,
195 struct key *dest_keyring);
196
197 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
198
199 /*
200 * keyctl() functions
201 */
202 extern long keyctl_get_keyring_ID(key_serial_t, int);
203 extern long keyctl_join_session_keyring(const char __user *);
204 extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
205 extern long keyctl_revoke_key(key_serial_t);
206 extern long keyctl_keyring_clear(key_serial_t);
207 extern long keyctl_keyring_link(key_serial_t, key_serial_t);
208 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
209 extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
210 extern long keyctl_keyring_search(key_serial_t, const char __user *,
211 const char __user *, key_serial_t);
212 extern long keyctl_read_key(key_serial_t, char __user *, size_t);
213 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
214 extern long keyctl_setperm_key(key_serial_t, key_perm_t);
215 extern long keyctl_instantiate_key(key_serial_t, const void __user *,
216 size_t, key_serial_t);
217 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
218 extern long keyctl_set_reqkey_keyring(int);
219 extern long keyctl_set_timeout(key_serial_t, unsigned);
220 extern long keyctl_assume_authority(key_serial_t);
221 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
222 size_t buflen);
223 extern long keyctl_session_to_parent(void);
224 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
225 extern long keyctl_instantiate_key_iov(key_serial_t,
226 const struct iovec __user *,
227 unsigned, key_serial_t);
228
229 extern long keyctl_instantiate_key_common(key_serial_t,
230 const struct iovec __user *,
231 unsigned, size_t, key_serial_t);
232
233 /*
234 * Debugging key validation
235 */
236 #ifdef KEY_DEBUGGING
237 extern void __key_check(const struct key *);
238
key_check(const struct key * key)239 static inline void key_check(const struct key *key)
240 {
241 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
242 __key_check(key);
243 }
244
245 #else
246
247 #define key_check(key) do {} while(0)
248
249 #endif
250
251 #endif /* _INTERNAL_H */
252