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Linux kernel mirror (for testing)
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linux
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#ifdef __KDEBUG
20#define kenter(FMT, ...) \
21 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
22#define kleave(FMT, ...) \
23 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
24#define kdebug(FMT, ...) \
25 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
26#else
27#define kenter(FMT, ...) \
28 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
29#define kleave(FMT, ...) \
30 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
31#define kdebug(FMT, ...) \
32 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
33#endif
34
35extern struct key_type key_type_dead;
36extern struct key_type key_type_user;
37extern struct key_type key_type_logon;
38
39/*****************************************************************************/
40/*
41 * Keep track of keys for a user.
42 *
43 * This needs to be separate to user_struct to avoid a refcount-loop
44 * (user_struct pins some keyrings which pin this struct).
45 *
46 * We also keep track of keys under request from userspace for this UID here.
47 */
48struct key_user {
49 struct rb_node node;
50 struct mutex cons_lock; /* construction initiation lock */
51 spinlock_t lock;
52 atomic_t usage; /* for accessing qnkeys & qnbytes */
53 atomic_t nkeys; /* number of keys */
54 atomic_t nikeys; /* number of instantiated keys */
55 uid_t uid;
56 struct user_namespace *user_ns;
57 int qnkeys; /* number of keys allocated to this user */
58 int qnbytes; /* number of bytes allocated to this user */
59};
60
61extern struct rb_root key_user_tree;
62extern spinlock_t key_user_lock;
63extern struct key_user root_key_user;
64
65extern struct key_user *key_user_lookup(uid_t uid,
66 struct user_namespace *user_ns);
67extern 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 */
73extern unsigned key_quota_root_maxkeys;
74extern unsigned key_quota_root_maxbytes;
75extern unsigned key_quota_maxkeys;
76extern unsigned key_quota_maxbytes;
77
78#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
79
80
81extern struct kmem_cache *key_jar;
82extern struct rb_root key_serial_tree;
83extern spinlock_t key_serial_lock;
84extern struct mutex key_construction_mutex;
85extern wait_queue_head_t request_key_conswq;
86
87
88extern struct key_type *key_type_lookup(const char *type);
89extern void key_type_put(struct key_type *ktype);
90
91extern int __key_link_begin(struct key *keyring,
92 const struct key_type *type,
93 const char *description,
94 unsigned long *_prealloc);
95extern int __key_link_check_live_key(struct key *keyring, struct key *key);
96extern void __key_link(struct key *keyring, struct key *key,
97 unsigned long *_prealloc);
98extern void __key_link_end(struct key *keyring,
99 struct key_type *type,
100 unsigned long prealloc);
101
102extern 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
107extern struct key *keyring_search_instkey(struct key *keyring,
108 key_serial_t target_id);
109
110typedef int (*key_match_func_t)(const struct key *, const void *);
111
112extern 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
119extern 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);
124extern 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
129extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
130
131extern int install_user_keyrings(void);
132extern int install_thread_keyring_to_cred(struct cred *);
133extern int install_process_keyring_to_cred(struct cred *);
134extern int install_session_keyring_to_cred(struct cred *, struct key *);
135
136extern 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
144extern int lookup_user_key_possessed(const struct key *key, const void *target);
145extern 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
151extern long join_session_keyring(const char *name);
152extern void key_change_session_keyring(struct task_work *twork);
153
154extern struct work_struct key_gc_work;
155extern unsigned key_gc_delay;
156extern void keyring_gc(struct key *keyring, time_t limit);
157extern void key_schedule_gc(time_t gc_at);
158extern void key_schedule_gc_links(void);
159extern void key_gc_keytype(struct key_type *ktype);
160
161extern 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 */
168static 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 */
185struct 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
194extern struct key_type key_type_request_key_auth;
195extern 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
200extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
201
202/*
203 * Determine whether a key is dead.
204 */
205static 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 */
216extern long keyctl_get_keyring_ID(key_serial_t, int);
217extern long keyctl_join_session_keyring(const char __user *);
218extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
219extern long keyctl_revoke_key(key_serial_t);
220extern long keyctl_keyring_clear(key_serial_t);
221extern long keyctl_keyring_link(key_serial_t, key_serial_t);
222extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
223extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
224extern long keyctl_keyring_search(key_serial_t, const char __user *,
225 const char __user *, key_serial_t);
226extern long keyctl_read_key(key_serial_t, char __user *, size_t);
227extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
228extern long keyctl_setperm_key(key_serial_t, key_perm_t);
229extern long keyctl_instantiate_key(key_serial_t, const void __user *,
230 size_t, key_serial_t);
231extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
232extern long keyctl_set_reqkey_keyring(int);
233extern long keyctl_set_timeout(key_serial_t, unsigned);
234extern long keyctl_assume_authority(key_serial_t);
235extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
236 size_t buflen);
237extern long keyctl_session_to_parent(void);
238extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
239extern long keyctl_instantiate_key_iov(key_serial_t,
240 const struct iovec __user *,
241 unsigned, key_serial_t);
242extern long keyctl_invalidate_key(key_serial_t);
243
244extern long keyctl_instantiate_key_common(key_serial_t,
245 const struct iovec __user *,
246 unsigned, size_t, key_serial_t);
247
248/*
249 * Debugging key validation
250 */
251#ifdef KEY_DEBUGGING
252extern void __key_check(const struct key *);
253
254static 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 */