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