xref: /openbmc/linux/security/keys/internal.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/key-type.h>
16 #include <linux/key-ui.h>
17 
18 static inline __attribute__((format(printf, 1, 2)))
19 void 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 "xxx" FMT"yyy\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 
39 extern 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  */
48 struct 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 	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 extern void key_user_put(struct key_user *user);
66 
67 /*
68  * key quota limits
69  * - root has its own separate limits to everyone else
70  */
71 extern unsigned key_quota_root_maxkeys;
72 extern unsigned key_quota_root_maxbytes;
73 extern unsigned key_quota_maxkeys;
74 extern unsigned key_quota_maxbytes;
75 
76 #define KEYQUOTA_LINK_BYTES	4		/* a link in a keyring is worth 4 bytes */
77 
78 
79 extern struct rb_root key_serial_tree;
80 extern spinlock_t key_serial_lock;
81 extern struct mutex key_construction_mutex;
82 extern wait_queue_head_t request_key_conswq;
83 
84 
85 extern int __key_link(struct key *keyring, struct key *key);
86 
87 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
88 				      const struct key_type *type,
89 				      const char *description,
90 				      key_perm_t perm);
91 
92 extern struct key *keyring_search_instkey(struct key *keyring,
93 					  key_serial_t target_id);
94 
95 typedef int (*key_match_func_t)(const struct key *, const void *);
96 
97 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
98 				    struct task_struct *tsk,
99 				    struct key_type *type,
100 				    const void *description,
101 				    key_match_func_t match);
102 
103 extern key_ref_t search_process_keyrings(struct key_type *type,
104 					 const void *description,
105 					 key_match_func_t match,
106 					 struct task_struct *tsk);
107 
108 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
109 
110 extern int install_thread_keyring(struct task_struct *tsk);
111 extern int install_process_keyring(struct task_struct *tsk);
112 
113 extern struct key *request_key_and_link(struct key_type *type,
114 					const char *description,
115 					const void *callout_info,
116 					size_t callout_len,
117 					void *aux,
118 					struct key *dest_keyring,
119 					unsigned long flags);
120 
121 /*
122  * request_key authorisation
123  */
124 struct request_key_auth {
125 	struct key		*target_key;
126 	struct task_struct	*context;
127 	void			*callout_info;
128 	size_t			callout_len;
129 	pid_t			pid;
130 };
131 
132 extern struct key_type key_type_request_key_auth;
133 extern struct key *request_key_auth_new(struct key *target,
134 					const void *callout_info,
135 					size_t callout_len);
136 
137 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
138 
139 /*
140  * keyctl functions
141  */
142 extern long keyctl_get_keyring_ID(key_serial_t, int);
143 extern long keyctl_join_session_keyring(const char __user *);
144 extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
145 extern long keyctl_revoke_key(key_serial_t);
146 extern long keyctl_keyring_clear(key_serial_t);
147 extern long keyctl_keyring_link(key_serial_t, key_serial_t);
148 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
149 extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
150 extern long keyctl_keyring_search(key_serial_t, const char __user *,
151 				  const char __user *, key_serial_t);
152 extern long keyctl_read_key(key_serial_t, char __user *, size_t);
153 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
154 extern long keyctl_setperm_key(key_serial_t, key_perm_t);
155 extern long keyctl_instantiate_key(key_serial_t, const void __user *,
156 				   size_t, key_serial_t);
157 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
158 extern long keyctl_set_reqkey_keyring(int);
159 extern long keyctl_set_timeout(key_serial_t, unsigned);
160 extern long keyctl_assume_authority(key_serial_t);
161 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
162 				size_t buflen);
163 
164 /*
165  * debugging key validation
166  */
167 #ifdef KEY_DEBUGGING
168 extern void __key_check(const struct key *);
169 
170 static inline void key_check(const struct key *key)
171 {
172 	if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
173 		__key_check(key);
174 }
175 
176 #else
177 
178 #define key_check(key) do {} while(0)
179 
180 #endif
181 
182 #endif /* _INTERNAL_H */
183