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Linux kernel mirror (for testing)
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linux
1/* internal.h: 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
18static inline __attribute__((format(printf, 1, 2)))
19void no_printk(const char *fmt, ...)
20{
21}
22
23#ifdef __KDEBUG
24#define kenter(FMT, ...) \
25 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
26#define kleave(FMT, ...) \
27 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
28#define kdebug(FMT, ...) \
29 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
30#else
31#define kenter(FMT, ...) \
32 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
33#define kleave(FMT, ...) \
34 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
35#define kdebug(FMT, ...) \
36 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
37#endif
38
39extern struct key_type key_type_user;
40
41/*****************************************************************************/
42/*
43 * keep track of keys for a user
44 * - this needs to be separate to user_struct to avoid a refcount-loop
45 * (user_struct pins some keyrings which pin this struct)
46 * - this also keeps track of keys under request from userspace for this UID
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 rb_root key_serial_tree;
82extern spinlock_t key_serial_lock;
83extern struct mutex key_construction_mutex;
84extern wait_queue_head_t request_key_conswq;
85
86
87extern struct key_type *key_type_lookup(const char *type);
88extern void key_type_put(struct key_type *ktype);
89
90extern int __key_link(struct key *keyring, struct key *key);
91
92extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
93 const struct key_type *type,
94 const char *description,
95 key_perm_t perm);
96
97extern struct key *keyring_search_instkey(struct key *keyring,
98 key_serial_t target_id);
99
100typedef int (*key_match_func_t)(const struct key *, const void *);
101
102extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
103 const struct cred *cred,
104 struct key_type *type,
105 const void *description,
106 key_match_func_t match);
107
108extern key_ref_t search_process_keyrings(struct key_type *type,
109 const void *description,
110 key_match_func_t match,
111 const struct cred *cred);
112
113extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
114
115extern int install_user_keyrings(void);
116extern int install_thread_keyring_to_cred(struct cred *);
117extern int install_process_keyring_to_cred(struct cred *);
118
119extern struct key *request_key_and_link(struct key_type *type,
120 const char *description,
121 const void *callout_info,
122 size_t callout_len,
123 void *aux,
124 struct key *dest_keyring,
125 unsigned long flags);
126
127extern key_ref_t lookup_user_key(key_serial_t id, int create, int partial,
128 key_perm_t perm);
129
130extern long join_session_keyring(const char *name);
131
132/*
133 * check to see whether permission is granted to use a key in the desired way
134 */
135extern int key_task_permission(const key_ref_t key_ref,
136 const struct cred *cred,
137 key_perm_t perm);
138
139static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
140{
141 return key_task_permission(key_ref, current_cred(), perm);
142}
143
144/* required permissions */
145#define KEY_VIEW 0x01 /* require permission to view attributes */
146#define KEY_READ 0x02 /* require permission to read content */
147#define KEY_WRITE 0x04 /* require permission to update / modify */
148#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
149#define KEY_LINK 0x10 /* require permission to link */
150#define KEY_SETATTR 0x20 /* require permission to change attributes */
151#define KEY_ALL 0x3f /* all the above permissions */
152
153/*
154 * request_key authorisation
155 */
156struct request_key_auth {
157 struct key *target_key;
158 struct key *dest_keyring;
159 const struct cred *cred;
160 void *callout_info;
161 size_t callout_len;
162 pid_t pid;
163};
164
165extern struct key_type key_type_request_key_auth;
166extern struct key *request_key_auth_new(struct key *target,
167 const void *callout_info,
168 size_t callout_len,
169 struct key *dest_keyring);
170
171extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
172
173/*
174 * keyctl functions
175 */
176extern long keyctl_get_keyring_ID(key_serial_t, int);
177extern long keyctl_join_session_keyring(const char __user *);
178extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
179extern long keyctl_revoke_key(key_serial_t);
180extern long keyctl_keyring_clear(key_serial_t);
181extern long keyctl_keyring_link(key_serial_t, key_serial_t);
182extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
183extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
184extern long keyctl_keyring_search(key_serial_t, const char __user *,
185 const char __user *, key_serial_t);
186extern long keyctl_read_key(key_serial_t, char __user *, size_t);
187extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
188extern long keyctl_setperm_key(key_serial_t, key_perm_t);
189extern long keyctl_instantiate_key(key_serial_t, const void __user *,
190 size_t, key_serial_t);
191extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
192extern long keyctl_set_reqkey_keyring(int);
193extern long keyctl_set_timeout(key_serial_t, unsigned);
194extern long keyctl_assume_authority(key_serial_t);
195extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
196 size_t buflen);
197
198/*
199 * debugging key validation
200 */
201#ifdef KEY_DEBUGGING
202extern void __key_check(const struct key *);
203
204static inline void key_check(const struct key *key)
205{
206 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
207 __key_check(key);
208}
209
210#else
211
212#define key_check(key) do {} while(0)
213
214#endif
215
216#endif /* _INTERNAL_H */