[linux-2.6-block.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>

struct iovec;

#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 keyring_index_key *index_key,
			    struct assoc_array_edit **_edit);
extern int __key_link_check_live_key(struct key *keyring, struct key *key);
extern void __key_link(struct key *key, struct assoc_array_edit **_edit);
extern void __key_link_end(struct key *keyring,
			   const struct keyring_index_key *index_key,
			   struct assoc_array_edit *edit);

extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
				    const struct keyring_index_key *index_key);

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

extern int iterate_over_keyring(const struct key *keyring,
				int (*func)(const struct key *key, void *data),
				void *data);

struct keyring_search_context {
	struct keyring_index_key index_key;
	const struct cred	*cred;
	struct key_match_data	match_data;
	unsigned		flags;
#define KEYRING_SEARCH_NO_STATE_CHECK	0x0001	/* Skip state checks */
#define KEYRING_SEARCH_DO_STATE_CHECK	0x0002	/* Override NO_STATE_CHECK */
#define KEYRING_SEARCH_NO_UPDATE_TIME	0x0004	/* Don't update times */
#define KEYRING_SEARCH_NO_CHECK_PERM	0x0008	/* Don't check permissions */
#define KEYRING_SEARCH_DETECT_TOO_DEEP	0x0010	/* Give an error on excessive depth */

	int (*iterator)(const void *object, void *iterator_data);

	/* Internal stuff */
	int			skipped_ret;
	bool			possessed;
	key_ref_t		result;
	struct timespec		now;
};

extern int key_default_cmp(const struct key *key,
			   const struct key_match_data *match_data);
extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
				    struct keyring_search_context *ctx);

extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);

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 struct key_match_data *match_data);
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, unsigned perm)
{
	return key_task_permission(key_ref, current_cred(), perm);
}

/*
 * 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(const 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);
#ifdef CONFIG_PERSISTENT_KEYRINGS
extern long keyctl_get_persistent(uid_t, key_serial_t);
extern unsigned persistent_keyring_expiry;
#else
static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
{
	return -EOPNOTSUPP;
}
#endif

/*
 * 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
a27bb332 KO	19	struct iovec;
a27bb332 KO	20
76181c13 DH	21	#ifdef __KDEBUG
76181c13 DH	22	#define kenter(FMT, ...) \
dd6f953a	23	printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
76181c13	24	#define kleave(FMT, ...) \
dd6f953a	25	printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
76181c13	26	#define kdebug(FMT, ...) \
d84f4f99	27	printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
3e30148c	28	#else
76181c13	29	#define kenter(FMT, ...) \
dd6f953a	30	no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
76181c13	31	#define kleave(FMT, ...) \
dd6f953a	32	no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
76181c13 DH	33	#define kdebug(FMT, ...) \
76181c13 DH	34	no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
3e30148c DH	35	#endif
3e30148c DH	36
0c061b57	37	extern struct key_type key_type_dead;
1da177e4	38	extern struct key_type key_type_user;
9f6ed2ca	39	extern struct key_type key_type_logon;
1da177e4 LT	40
	41	/*****************************************************************************/
	42	/*
973c9f4f DH	43	* Keep track of keys for a user.
	44	*
	45	* This needs to be separate to user_struct to avoid a refcount-loop
	46	* (user_struct pins some keyrings which pin this struct).
	47	*
	48	* We also keep track of keys under request from userspace for this UID here.
1da177e4 LT	49	*/
	50	struct key_user {
	51	struct rb_node node;
76181c13	52	struct mutex cons_lock; /* construction initiation lock */
1da177e4 LT	53	spinlock_t lock;
	54	atomic_t usage; /* for accessing qnkeys & qnbytes */
	55	atomic_t nkeys; /* number of keys */
	56	atomic_t nikeys; /* number of instantiated keys */
9a56c2db	57	kuid_t uid;
1da177e4 LT	58	int qnkeys; /* number of keys allocated to this user */
	59	int qnbytes; /* number of bytes allocated to this user */
	60	};
	61
1da177e4 LT	62	extern struct rb_root key_user_tree;
	63	extern spinlock_t key_user_lock;
	64	extern struct key_user root_key_user;
	65
9a56c2db	66	extern struct key_user *key_user_lookup(kuid_t uid);
1da177e4 LT	67	extern void key_user_put(struct key_user *user);
1da177e4 LT	68
0b77f5bf	69	/*
973c9f4f	70	* Key quota limits.
0b77f5bf DH	71	* - root has its own separate limits to everyone else
	72	*/
	73	extern unsigned key_quota_root_maxkeys;
	74	extern unsigned key_quota_root_maxbytes;
	75	extern unsigned key_quota_maxkeys;
	76	extern unsigned key_quota_maxbytes;
	77
	78	#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
1da177e4 LT	79
1da177e4 LT	80
8bc16dea	81	extern struct kmem_cache *key_jar;
1da177e4 LT	82	extern struct rb_root key_serial_tree;
1da177e4 LT	83	extern spinlock_t key_serial_lock;
76181c13	84	extern struct mutex key_construction_mutex;
1da177e4 LT	85	extern wait_queue_head_t request_key_conswq;
	86
	87
e9e349b0 DH	88	extern struct key_type key_type_lookup(const char type);
	89	extern void key_type_put(struct key_type *ktype);
	90
f70e2e06	91	extern int __key_link_begin(struct key *keyring,
16feef43	92	const struct keyring_index_key *index_key,
b2a4df20	93	struct assoc_array_edit **_edit);
f70e2e06	94	extern int __key_link_check_live_key(struct key keyring, struct key key);
b2a4df20	95	extern void __key_link(struct key key, struct assoc_array_edit *_edit);
f70e2e06	96	extern void __key_link_end(struct key *keyring,
16feef43	97	const struct keyring_index_key *index_key,
b2a4df20	98	struct assoc_array_edit *edit);
1da177e4	99
b2a4df20 DH	100	extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
b2a4df20 DH	101	const struct keyring_index_key *index_key);
1da177e4	102
3e30148c DH	103	extern struct key keyring_search_instkey(struct key keyring,
	104	key_serial_t target_id);
	105
b2a4df20 DH	106	extern int iterate_over_keyring(const struct key *keyring,
	107	int (func)(const struct key key, void *data),
	108	void *data);
	109
4bdf0bc3 DH	110	struct keyring_search_context {
	111	struct keyring_index_key index_key;
	112	const struct cred *cred;
46291959	113	struct key_match_data match_data;
4bdf0bc3	114	unsigned flags;
614d8c39 DH	115	#define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */
	116	#define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */
	117	#define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */
	118	#define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */
	119	#define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */
4bdf0bc3	120
b2a4df20 DH	121	int (iterator)(const void object, void *iterator_data);
b2a4df20 DH	122
4bdf0bc3 DH	123	/* Internal stuff */
	124	int skipped_ret;
	125	bool possessed;
	126	key_ref_t result;
	127	struct timespec now;
	128	};
	129
c06cfb08 DH	130	extern int key_default_cmp(const struct key *key,
c06cfb08 DH	131	const struct key_match_data *match_data);
664cceb0	132	extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
4bdf0bc3 DH	133	struct keyring_search_context *ctx);
	134
	135	extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
	136	extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
1da177e4	137
69664cf1	138	extern struct key find_keyring_by_name(const char name, bool skip_perm_check);
1da177e4	139
8bbf4976	140	extern int install_user_keyrings(void);
d84f4f99 DH	141	extern int install_thread_keyring_to_cred(struct cred *);
d84f4f99 DH	142	extern int install_process_keyring_to_cred(struct cred *);
685bfd2c	143	extern int install_session_keyring_to_cred(struct cred , struct key );
3e30148c DH	144
	145	extern struct key request_key_and_link(struct key_type type,
	146	const char *description,
4a38e122 DH	147	const void *callout_info,
4a38e122 DH	148	size_t callout_len,
4e54f085	149	void *aux,
7e047ef5 DH	150	struct key *dest_keyring,
7e047ef5 DH	151	unsigned long flags);
3e30148c	152
46291959 DH	153	extern int lookup_user_key_possessed(const struct key *key,
46291959 DH	154	const struct key_match_data *match_data);
5593122e	155	extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
e9e349b0	156	key_perm_t perm);
5593122e DH	157	#define KEY_LOOKUP_CREATE 0x01
	158	#define KEY_LOOKUP_PARTIAL 0x02
	159	#define KEY_LOOKUP_FOR_UNLINK 0x04
e9e349b0 DH	160
e9e349b0 DH	161	extern long join_session_keyring(const char *name);
67d12145	162	extern void key_change_session_keyring(struct callback_head *twork);
e9e349b0	163
0c061b57	164	extern struct work_struct key_gc_work;
5d135440 DH	165	extern unsigned key_gc_delay;
5d135440 DH	166	extern void keyring_gc(struct key *keyring, time_t limit);
fd75815f DH	167	extern void key_schedule_gc(time_t gc_at);
fd75815f DH	168	extern void key_schedule_gc_links(void);
0c061b57	169	extern void key_gc_keytype(struct key_type *ktype);
5d135440	170
e9e349b0	171	extern int key_task_permission(const key_ref_t key_ref,
d84f4f99	172	const struct cred *cred,
e9e349b0 DH	173	key_perm_t perm);
e9e349b0 DH	174
973c9f4f DH	175	/*
	176	* Check to see whether permission is granted to use a key in the desired way.
	177	*/
f5895943	178	static inline int key_permission(const key_ref_t key_ref, unsigned perm)
e9e349b0	179	{
d84f4f99	180	return key_task_permission(key_ref, current_cred(), perm);
e9e349b0 DH	181	}
e9e349b0 DH	182
3e30148c	183	/*
973c9f4f	184	* Authorisation record for request_key().
3e30148c DH	185	*/
	186	struct request_key_auth {
	187	struct key *target_key;
8bbf4976	188	struct key *dest_keyring;
d84f4f99	189	const struct cred *cred;
4a38e122 DH	190	void *callout_info;
4a38e122 DH	191	size_t callout_len;
3e30148c DH	192	pid_t pid;
	193	};
	194
	195	extern struct key_type key_type_request_key_auth;
	196	extern struct key request_key_auth_new(struct key target,
4a38e122	197	const void *callout_info,
8bbf4976 DH	198	size_t callout_len,
8bbf4976 DH	199	struct key *dest_keyring);
3e30148c DH	200
3e30148c DH	201	extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
1da177e4	202
fd75815f DH	203	/*
	204	* Determine whether a key is dead.
	205	*/
7e55ca6d	206	static inline bool key_is_dead(const struct key *key, time_t limit)
fd75815f DH	207	{
	208	return
	209	key->flags & ((1 << KEY_FLAG_DEAD) \|
	210	(1 << KEY_FLAG_INVALIDATED)) \|\|
	211	(key->expiry > 0 && key->expiry <= limit);
	212	}
	213
1da177e4	214	/*
973c9f4f	215	* keyctl() functions
1da177e4 LT	216	*/
	217	extern long keyctl_get_keyring_ID(key_serial_t, int);
	218	extern long keyctl_join_session_keyring(const char __user *);
	219	extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
	220	extern long keyctl_revoke_key(key_serial_t);
	221	extern long keyctl_keyring_clear(key_serial_t);
	222	extern long keyctl_keyring_link(key_serial_t, key_serial_t);
	223	extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
	224	extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
	225	extern long keyctl_keyring_search(key_serial_t, const char __user *,
	226	const char __user *, key_serial_t);
	227	extern long keyctl_read_key(key_serial_t, char __user *, size_t);
	228	extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
	229	extern long keyctl_setperm_key(key_serial_t, key_perm_t);
	230	extern long keyctl_instantiate_key(key_serial_t, const void __user *,
	231	size_t, key_serial_t);
	232	extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
3e30148c	233	extern long keyctl_set_reqkey_keyring(int);
017679c4	234	extern long keyctl_set_timeout(key_serial_t, unsigned);
b5f545c8	235	extern long keyctl_assume_authority(key_serial_t);
70a5bb72 DH	236	extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
70a5bb72 DH	237	size_t buflen);
ee18d64c	238	extern long keyctl_session_to_parent(void);
fdd1b945	239	extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
ee009e4a DH	240	extern long keyctl_instantiate_key_iov(key_serial_t,
	241	const struct iovec __user *,
	242	unsigned, key_serial_t);
fd75815f	243	extern long keyctl_invalidate_key(key_serial_t);
ee009e4a DH	244
ee009e4a DH	245	extern long keyctl_instantiate_key_common(key_serial_t,
423b9788	246	const struct iovec *,
ee009e4a	247	unsigned, size_t, key_serial_t);
f36f8c75 DH	248	#ifdef CONFIG_PERSISTENT_KEYRINGS
	249	extern long keyctl_get_persistent(uid_t, key_serial_t);
	250	extern unsigned persistent_keyring_expiry;
	251	#else
	252	static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
	253	{
	254	return -EOPNOTSUPP;
	255	}
	256	#endif
1da177e4 LT	257
1da177e4 LT	258	/*
973c9f4f	259	* Debugging key validation
1da177e4 LT	260	*/
	261	#ifdef KEY_DEBUGGING
	262	extern void __key_check(const struct key *);
	263
	264	static inline void key_check(const struct key *key)
	265	{
	266	if (key && (IS_ERR(key) \|\| key->magic != KEY_DEBUG_MAGIC))
	267	__key_check(key);
	268	}
	269
	270	#else
	271
	272	#define key_check(key) do {} while(0)
	273
	274	#endif
	275
	276	#endif /* _INTERNAL_H */