[deliverable/linux.git] / security / keys / internal.h

/* Authentication token and access key management internal defs
 *
 * Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#ifndef _INTERNAL_H
#define _INTERNAL_H

#include <linux/sched.h>
#include <linux/key-type.h>
#include <linux/task_work.h>

#ifdef __KDEBUG
#define kenter(FMT, ...) \
	printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) \
	printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) \
	printk(KERN_DEBUG "   "FMT"\n", ##__VA_ARGS__)
#else
#define kenter(FMT, ...) \
	no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) \
	no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) \
	no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
#endif

extern struct key_type key_type_dead;
extern struct key_type key_type_user;
extern struct key_type key_type_logon;

/*****************************************************************************/
/*
 * Keep track of keys for a user.
 *
 * This needs to be separate to user_struct to avoid a refcount-loop
 * (user_struct pins some keyrings which pin this struct).
 *
 * We also keep track of keys under request from userspace for this UID here.
 */
struct key_user {
	struct rb_node		node;
	struct mutex		cons_lock;	/* construction initiation lock */
	spinlock_t		lock;
	atomic_t		usage;		/* for accessing qnkeys & qnbytes */
	atomic_t		nkeys;		/* number of keys */
	atomic_t		nikeys;		/* number of instantiated keys */
	kuid_t			uid;
	int			qnkeys;		/* number of keys allocated to this user */
	int			qnbytes;	/* number of bytes allocated to this user */
};

extern struct rb_root	key_user_tree;
extern spinlock_t	key_user_lock;
extern struct key_user	root_key_user;

extern struct key_user *key_user_lookup(kuid_t uid);
extern void key_user_put(struct key_user *user);

/*
 * Key quota limits.
 * - root has its own separate limits to everyone else
 */
extern unsigned key_quota_root_maxkeys;
extern unsigned key_quota_root_maxbytes;
extern unsigned key_quota_maxkeys;
extern unsigned key_quota_maxbytes;

#define KEYQUOTA_LINK_BYTES	4		/* a link in a keyring is worth 4 bytes */


extern struct kmem_cache *key_jar;
extern struct rb_root key_serial_tree;
extern spinlock_t key_serial_lock;
extern struct mutex key_construction_mutex;
extern wait_queue_head_t request_key_conswq;


extern struct key_type *key_type_lookup(const char *type);
extern void key_type_put(struct key_type *ktype);

extern int __key_link_begin(struct key *keyring,
			    const struct key_type *type,
			    const char *description,
			    unsigned long *_prealloc);
extern int __key_link_check_live_key(struct key *keyring, struct key *key);
extern void __key_link(struct key *keyring, struct key *key,
		       unsigned long *_prealloc);
extern void __key_link_end(struct key *keyring,
			   struct key_type *type,
			   unsigned long prealloc);

extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
				      const struct key_type *type,
				      const char *description,
				      key_perm_t perm);

extern struct key *keyring_search_instkey(struct key *keyring,
					  key_serial_t target_id);

typedef int (*key_match_func_t)(const struct key *, const void *);

extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
				    const struct cred *cred,
				    struct key_type *type,
				    const void *description,
				    key_match_func_t match,
				    bool no_state_check);

extern key_ref_t search_my_process_keyrings(struct key_type *type,
					    const void *description,
					    key_match_func_t match,
					    bool no_state_check,
					    const struct cred *cred);
extern key_ref_t search_process_keyrings(struct key_type *type,
					 const void *description,
					 key_match_func_t match,
					 const struct cred *cred);

extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);

extern int install_user_keyrings(void);
extern int install_thread_keyring_to_cred(struct cred *);
extern int install_process_keyring_to_cred(struct cred *);
extern int install_session_keyring_to_cred(struct cred *, struct key *);

extern struct key *request_key_and_link(struct key_type *type,
					const char *description,
					const void *callout_info,
					size_t callout_len,
					void *aux,
					struct key *dest_keyring,
					unsigned long flags);

extern int lookup_user_key_possessed(const struct key *key, const void *target);
extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
				 key_perm_t perm);
#define KEY_LOOKUP_CREATE	0x01
#define KEY_LOOKUP_PARTIAL	0x02
#define KEY_LOOKUP_FOR_UNLINK	0x04

extern long join_session_keyring(const char *name);
extern void key_change_session_keyring(struct callback_head *twork);

extern struct work_struct key_gc_work;
extern unsigned key_gc_delay;
extern void keyring_gc(struct key *keyring, time_t limit);
extern void key_schedule_gc(time_t gc_at);
extern void key_schedule_gc_links(void);
extern void key_gc_keytype(struct key_type *ktype);

extern int key_task_permission(const key_ref_t key_ref,
			       const struct cred *cred,
			       key_perm_t perm);

/*
 * Check to see whether permission is granted to use a key in the desired way.
 */
static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
{
	return key_task_permission(key_ref, current_cred(), perm);
}

/* required permissions */
#define	KEY_VIEW	0x01	/* require permission to view attributes */
#define	KEY_READ	0x02	/* require permission to read content */
#define	KEY_WRITE	0x04	/* require permission to update / modify */
#define	KEY_SEARCH	0x08	/* require permission to search (keyring) or find (key) */
#define	KEY_LINK	0x10	/* require permission to link */
#define	KEY_SETATTR	0x20	/* require permission to change attributes */
#define	KEY_ALL		0x3f	/* all the above permissions */

/*
 * Authorisation record for request_key().
 */
struct request_key_auth {
	struct key		*target_key;
	struct key		*dest_keyring;
	const struct cred	*cred;
	void			*callout_info;
	size_t			callout_len;
	pid_t			pid;
};

extern struct key_type key_type_request_key_auth;
extern struct key *request_key_auth_new(struct key *target,
					const void *callout_info,
					size_t callout_len,
					struct key *dest_keyring);

extern struct key *key_get_instantiation_authkey(key_serial_t target_id);

/*
 * Determine whether a key is dead.
 */
static inline bool key_is_dead(struct key *key, time_t limit)
{
	return
		key->flags & ((1 << KEY_FLAG_DEAD) |
			      (1 << KEY_FLAG_INVALIDATED)) ||
		(key->expiry > 0 && key->expiry <= limit);
}

/*
 * keyctl() functions
 */
extern long keyctl_get_keyring_ID(key_serial_t, int);
extern long keyctl_join_session_keyring(const char __user *);
extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
extern long keyctl_revoke_key(key_serial_t);
extern long keyctl_keyring_clear(key_serial_t);
extern long keyctl_keyring_link(key_serial_t, key_serial_t);
extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
extern long keyctl_keyring_search(key_serial_t, const char __user *,
				  const char __user *, key_serial_t);
extern long keyctl_read_key(key_serial_t, char __user *, size_t);
extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
extern long keyctl_setperm_key(key_serial_t, key_perm_t);
extern long keyctl_instantiate_key(key_serial_t, const void __user *,
				   size_t, key_serial_t);
extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
extern long keyctl_set_reqkey_keyring(int);
extern long keyctl_set_timeout(key_serial_t, unsigned);
extern long keyctl_assume_authority(key_serial_t);
extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
				size_t buflen);
extern long keyctl_session_to_parent(void);
extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
extern long keyctl_instantiate_key_iov(key_serial_t,
				       const struct iovec __user *,
				       unsigned, key_serial_t);
extern long keyctl_invalidate_key(key_serial_t);

extern long keyctl_instantiate_key_common(key_serial_t,
					  const struct iovec *,
					  unsigned, size_t, key_serial_t);

/*
 * Debugging key validation
 */
#ifdef KEY_DEBUGGING
extern void __key_check(const struct key *);

static inline void key_check(const struct key *key)
{
	if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
		__key_check(key);
}

#else

#define key_check(key) do {} while(0)

#endif

#endif /* _INTERNAL_H */
Commit	Line	Data
973c9f4f	1	/* Authentication token and access key management internal defs
1da177e4	2	*
76181c13	3	* Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
1da177e4 LT	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
d84f4f99	15	#include <linux/sched.h>
76181c13	16	#include <linux/key-type.h>
413cd3d9	17	#include <linux/task_work.h>
1da177e4	18
76181c13 DH	19	#ifdef __KDEBUG
76181c13 DH	20	#define kenter(FMT, ...) \
dd6f953a	21	printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
76181c13	22	#define kleave(FMT, ...) \
dd6f953a	23	printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
76181c13	24	#define kdebug(FMT, ...) \
d84f4f99	25	printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
3e30148c	26	#else
76181c13	27	#define kenter(FMT, ...) \
dd6f953a	28	no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
76181c13	29	#define kleave(FMT, ...) \
dd6f953a	30	no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
76181c13 DH	31	#define kdebug(FMT, ...) \
76181c13 DH	32	no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
3e30148c DH	33	#endif
3e30148c DH	34
0c061b57	35	extern struct key_type key_type_dead;
1da177e4	36	extern struct key_type key_type_user;
9f6ed2ca	37	extern struct key_type key_type_logon;
1da177e4 LT	38
	39	/*****************************************************************************/
	40	/*
973c9f4f DH	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.
1da177e4 LT	47	*/
	48	struct key_user {
	49	struct rb_node node;
76181c13	50	struct mutex cons_lock; /* construction initiation lock */
1da177e4 LT	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 */
9a56c2db	55	kuid_t uid;
1da177e4 LT	56	int qnkeys; /* number of keys allocated to this user */
	57	int qnbytes; /* number of bytes allocated to this user */
	58	};
	59
1da177e4 LT	60	extern struct rb_root key_user_tree;
	61	extern spinlock_t key_user_lock;
	62	extern struct key_user root_key_user;
	63
9a56c2db	64	extern struct key_user *key_user_lookup(kuid_t uid);
1da177e4 LT	65	extern void key_user_put(struct key_user *user);
1da177e4 LT	66
0b77f5bf	67	/*
973c9f4f	68	* Key quota limits.
0b77f5bf DH	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 */
1da177e4 LT	77
1da177e4 LT	78
8bc16dea	79	extern struct kmem_cache *key_jar;
1da177e4 LT	80	extern struct rb_root key_serial_tree;
1da177e4 LT	81	extern spinlock_t key_serial_lock;
76181c13	82	extern struct mutex key_construction_mutex;
1da177e4 LT	83	extern wait_queue_head_t request_key_conswq;
	84
	85
e9e349b0 DH	86	extern struct key_type key_type_lookup(const char type);
	87	extern void key_type_put(struct key_type *ktype);
	88
f70e2e06 DH	89	extern int __key_link_begin(struct key *keyring,
	90	const struct key_type *type,
	91	const char *description,
ceb73c12	92	unsigned long *_prealloc);
f70e2e06 DH	93	extern int __key_link_check_live_key(struct key keyring, struct key key);
f70e2e06 DH	94	extern void __key_link(struct key keyring, struct key key,
ceb73c12	95	unsigned long *_prealloc);
f70e2e06 DH	96	extern void __key_link_end(struct key *keyring,
f70e2e06 DH	97	struct key_type *type,
ceb73c12	98	unsigned long prealloc);
1da177e4	99
664cceb0 DH	100	extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
	101	const struct key_type *type,
	102	const char *description,
	103	key_perm_t perm);
1da177e4	104
3e30148c DH	105	extern struct key keyring_search_instkey(struct key keyring,
	106	key_serial_t target_id);
	107
1da177e4 LT	108	typedef int (key_match_func_t)(const struct key , const void *);
1da177e4 LT	109
664cceb0	110	extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
d84f4f99	111	const struct cred *cred,
664cceb0 DH	112	struct key_type *type,
664cceb0 DH	113	const void *description,
78b7280c DH	114	key_match_func_t match,
78b7280c DH	115	bool no_state_check);
1da177e4	116
927942aa DH	117	extern key_ref_t search_my_process_keyrings(struct key_type *type,
	118	const void *description,
	119	key_match_func_t match,
78b7280c	120	bool no_state_check,
927942aa	121	const struct cred *cred);
664cceb0 DH	122	extern key_ref_t search_process_keyrings(struct key_type *type,
	123	const void *description,
	124	key_match_func_t match,
d84f4f99	125	const struct cred *cred);
1da177e4	126
69664cf1	127	extern struct key find_keyring_by_name(const char name, bool skip_perm_check);
1da177e4	128
8bbf4976	129	extern int install_user_keyrings(void);
d84f4f99 DH	130	extern int install_thread_keyring_to_cred(struct cred *);
d84f4f99 DH	131	extern int install_process_keyring_to_cred(struct cred *);
685bfd2c	132	extern int install_session_keyring_to_cred(struct cred , struct key );
3e30148c DH	133
	134	extern struct key request_key_and_link(struct key_type type,
	135	const char *description,
4a38e122 DH	136	const void *callout_info,
4a38e122 DH	137	size_t callout_len,
4e54f085	138	void *aux,
7e047ef5 DH	139	struct key *dest_keyring,
7e047ef5 DH	140	unsigned long flags);
3e30148c	141
927942aa	142	extern int lookup_user_key_possessed(const struct key key, const void target);
5593122e	143	extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
e9e349b0	144	key_perm_t perm);
5593122e DH	145	#define KEY_LOOKUP_CREATE 0x01
	146	#define KEY_LOOKUP_PARTIAL 0x02
	147	#define KEY_LOOKUP_FOR_UNLINK 0x04
e9e349b0 DH	148
e9e349b0 DH	149	extern long join_session_keyring(const char *name);
67d12145	150	extern void key_change_session_keyring(struct callback_head *twork);
e9e349b0	151
0c061b57	152	extern struct work_struct key_gc_work;
5d135440 DH	153	extern unsigned key_gc_delay;
5d135440 DH	154	extern void keyring_gc(struct key *keyring, time_t limit);
fd75815f DH	155	extern void key_schedule_gc(time_t gc_at);
fd75815f DH	156	extern void key_schedule_gc_links(void);
0c061b57	157	extern void key_gc_keytype(struct key_type *ktype);
5d135440	158
e9e349b0	159	extern int key_task_permission(const key_ref_t key_ref,
d84f4f99	160	const struct cred *cred,
e9e349b0 DH	161	key_perm_t perm);
e9e349b0 DH	162
973c9f4f DH	163	/*
	164	* Check to see whether permission is granted to use a key in the desired way.
	165	*/
e9e349b0 DH	166	static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
e9e349b0 DH	167	{
d84f4f99	168	return key_task_permission(key_ref, current_cred(), perm);
e9e349b0 DH	169	}
	170
	171	/* required permissions */
	172	#define KEY_VIEW 0x01 /* require permission to view attributes */
	173	#define KEY_READ 0x02 /* require permission to read content */
	174	#define KEY_WRITE 0x04 /* require permission to update / modify */
	175	#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
	176	#define KEY_LINK 0x10 /* require permission to link */
	177	#define KEY_SETATTR 0x20 /* require permission to change attributes */
	178	#define KEY_ALL 0x3f /* all the above permissions */
	179
3e30148c	180	/*
973c9f4f	181	* Authorisation record for request_key().
3e30148c DH	182	*/
	183	struct request_key_auth {
	184	struct key *target_key;
8bbf4976	185	struct key *dest_keyring;
d84f4f99	186	const struct cred *cred;
4a38e122 DH	187	void *callout_info;
4a38e122 DH	188	size_t callout_len;
3e30148c DH	189	pid_t pid;
	190	};
	191
	192	extern struct key_type key_type_request_key_auth;
	193	extern struct key request_key_auth_new(struct key target,
4a38e122	194	const void *callout_info,
8bbf4976 DH	195	size_t callout_len,
8bbf4976 DH	196	struct key *dest_keyring);
3e30148c DH	197
3e30148c DH	198	extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
1da177e4	199
fd75815f DH	200	/*
	201	* Determine whether a key is dead.
	202	*/
	203	static inline bool key_is_dead(struct key *key, time_t limit)
	204	{
	205	return
	206	key->flags & ((1 << KEY_FLAG_DEAD) \|
	207	(1 << KEY_FLAG_INVALIDATED)) \|\|
	208	(key->expiry > 0 && key->expiry <= limit);
	209	}
	210
1da177e4	211	/*
973c9f4f	212	* keyctl() functions
1da177e4 LT	213	*/
	214	extern long keyctl_get_keyring_ID(key_serial_t, int);
	215	extern long keyctl_join_session_keyring(const char __user *);
	216	extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
	217	extern long keyctl_revoke_key(key_serial_t);
	218	extern long keyctl_keyring_clear(key_serial_t);
	219	extern long keyctl_keyring_link(key_serial_t, key_serial_t);
	220	extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
	221	extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
	222	extern long keyctl_keyring_search(key_serial_t, const char __user *,
	223	const char __user *, key_serial_t);
	224	extern long keyctl_read_key(key_serial_t, char __user *, size_t);
	225	extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
	226	extern long keyctl_setperm_key(key_serial_t, key_perm_t);
	227	extern long keyctl_instantiate_key(key_serial_t, const void __user *,
	228	size_t, key_serial_t);
	229	extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
3e30148c	230	extern long keyctl_set_reqkey_keyring(int);
017679c4	231	extern long keyctl_set_timeout(key_serial_t, unsigned);
b5f545c8	232	extern long keyctl_assume_authority(key_serial_t);
70a5bb72 DH	233	extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
70a5bb72 DH	234	size_t buflen);
ee18d64c	235	extern long keyctl_session_to_parent(void);
fdd1b945	236	extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
ee009e4a DH	237	extern long keyctl_instantiate_key_iov(key_serial_t,
	238	const struct iovec __user *,
	239	unsigned, key_serial_t);
fd75815f	240	extern long keyctl_invalidate_key(key_serial_t);
ee009e4a DH	241
ee009e4a DH	242	extern long keyctl_instantiate_key_common(key_serial_t,
423b9788	243	const struct iovec *,
ee009e4a	244	unsigned, size_t, key_serial_t);
1da177e4 LT	245
1da177e4 LT	246	/*
973c9f4f	247	* Debugging key validation
1da177e4 LT	248	*/
	249	#ifdef KEY_DEBUGGING
	250	extern void __key_check(const struct key *);
	251
	252	static inline void key_check(const struct key *key)
	253	{
	254	if (key && (IS_ERR(key) \|\| key->magic != KEY_DEBUG_MAGIC))
	255	__key_check(key);
	256	}
	257
	258	#else
	259
	260	#define key_check(key) do {} while(0)
	261
	262	#endif
	263
	264	#endif /* _INTERNAL_H */