357 строки
11 KiB
C
357 строки
11 KiB
C
/* key.h: authentication token and access key management
|
|
*
|
|
* Copyright (C) 2004 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.
|
|
*
|
|
*
|
|
* See Documentation/keys.txt for information on keys/keyrings.
|
|
*/
|
|
|
|
#ifndef _LINUX_KEY_H
|
|
#define _LINUX_KEY_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/list.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/rcupdate.h>
|
|
#include <asm/atomic.h>
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
/* key handle serial number */
|
|
typedef int32_t key_serial_t;
|
|
|
|
/* key handle permissions mask */
|
|
typedef uint32_t key_perm_t;
|
|
|
|
struct key;
|
|
|
|
#ifdef CONFIG_KEYS
|
|
|
|
#undef KEY_DEBUGGING
|
|
|
|
#define KEY_POS_VIEW 0x01000000 /* possessor can view a key's attributes */
|
|
#define KEY_POS_READ 0x02000000 /* possessor can read key payload / view keyring */
|
|
#define KEY_POS_WRITE 0x04000000 /* possessor can update key payload / add link to keyring */
|
|
#define KEY_POS_SEARCH 0x08000000 /* possessor can find a key in search / search a keyring */
|
|
#define KEY_POS_LINK 0x10000000 /* possessor can create a link to a key/keyring */
|
|
#define KEY_POS_SETATTR 0x20000000 /* possessor can set key attributes */
|
|
#define KEY_POS_ALL 0x3f000000
|
|
|
|
#define KEY_USR_VIEW 0x00010000 /* user permissions... */
|
|
#define KEY_USR_READ 0x00020000
|
|
#define KEY_USR_WRITE 0x00040000
|
|
#define KEY_USR_SEARCH 0x00080000
|
|
#define KEY_USR_LINK 0x00100000
|
|
#define KEY_USR_SETATTR 0x00200000
|
|
#define KEY_USR_ALL 0x003f0000
|
|
|
|
#define KEY_GRP_VIEW 0x00000100 /* group permissions... */
|
|
#define KEY_GRP_READ 0x00000200
|
|
#define KEY_GRP_WRITE 0x00000400
|
|
#define KEY_GRP_SEARCH 0x00000800
|
|
#define KEY_GRP_LINK 0x00001000
|
|
#define KEY_GRP_SETATTR 0x00002000
|
|
#define KEY_GRP_ALL 0x00003f00
|
|
|
|
#define KEY_OTH_VIEW 0x00000001 /* third party permissions... */
|
|
#define KEY_OTH_READ 0x00000002
|
|
#define KEY_OTH_WRITE 0x00000004
|
|
#define KEY_OTH_SEARCH 0x00000008
|
|
#define KEY_OTH_LINK 0x00000010
|
|
#define KEY_OTH_SETATTR 0x00000020
|
|
#define KEY_OTH_ALL 0x0000003f
|
|
|
|
struct seq_file;
|
|
struct user_struct;
|
|
struct signal_struct;
|
|
|
|
struct key_type;
|
|
struct key_owner;
|
|
struct keyring_list;
|
|
struct keyring_name;
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* key reference with possession attribute handling
|
|
*
|
|
* NOTE! key_ref_t is a typedef'd pointer to a type that is not actually
|
|
* defined. This is because we abuse the bottom bit of the reference to carry a
|
|
* flag to indicate whether the calling process possesses that key in one of
|
|
* its keyrings.
|
|
*
|
|
* the key_ref_t has been made a separate type so that the compiler can reject
|
|
* attempts to dereference it without proper conversion.
|
|
*
|
|
* the three functions are used to assemble and disassemble references
|
|
*/
|
|
typedef struct __key_reference_with_attributes *key_ref_t;
|
|
|
|
static inline key_ref_t make_key_ref(const struct key *key,
|
|
unsigned long possession)
|
|
{
|
|
return (key_ref_t) ((unsigned long) key | possession);
|
|
}
|
|
|
|
static inline struct key *key_ref_to_ptr(const key_ref_t key_ref)
|
|
{
|
|
return (struct key *) ((unsigned long) key_ref & ~1UL);
|
|
}
|
|
|
|
static inline unsigned long is_key_possessed(const key_ref_t key_ref)
|
|
{
|
|
return (unsigned long) key_ref & 1UL;
|
|
}
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* authentication token / access credential / keyring
|
|
* - types of key include:
|
|
* - keyrings
|
|
* - disk encryption IDs
|
|
* - Kerberos TGTs and tickets
|
|
*/
|
|
struct key {
|
|
atomic_t usage; /* number of references */
|
|
key_serial_t serial; /* key serial number */
|
|
struct rb_node serial_node;
|
|
struct key_type *type; /* type of key */
|
|
struct rw_semaphore sem; /* change vs change sem */
|
|
struct key_user *user; /* owner of this key */
|
|
void *security; /* security data for this key */
|
|
time_t expiry; /* time at which key expires (or 0) */
|
|
uid_t uid;
|
|
gid_t gid;
|
|
key_perm_t perm; /* access permissions */
|
|
unsigned short quotalen; /* length added to quota */
|
|
unsigned short datalen; /* payload data length
|
|
* - may not match RCU dereferenced payload
|
|
* - payload should contain own length
|
|
*/
|
|
|
|
#ifdef KEY_DEBUGGING
|
|
unsigned magic;
|
|
#define KEY_DEBUG_MAGIC 0x18273645u
|
|
#define KEY_DEBUG_MAGIC_X 0xf8e9dacbu
|
|
#endif
|
|
|
|
unsigned long flags; /* status flags (change with bitops) */
|
|
#define KEY_FLAG_INSTANTIATED 0 /* set if key has been instantiated */
|
|
#define KEY_FLAG_DEAD 1 /* set if key type has been deleted */
|
|
#define KEY_FLAG_REVOKED 2 /* set if key had been revoked */
|
|
#define KEY_FLAG_IN_QUOTA 3 /* set if key consumes quota */
|
|
#define KEY_FLAG_USER_CONSTRUCT 4 /* set if key is being constructed in userspace */
|
|
#define KEY_FLAG_NEGATIVE 5 /* set if key is negative */
|
|
|
|
/* the description string
|
|
* - this is used to match a key against search criteria
|
|
* - this should be a printable string
|
|
* - eg: for krb5 AFS, this might be "afs@REDHAT.COM"
|
|
*/
|
|
char *description;
|
|
|
|
/* type specific data
|
|
* - this is used by the keyring type to index the name
|
|
*/
|
|
union {
|
|
struct list_head link;
|
|
} type_data;
|
|
|
|
/* key data
|
|
* - this is used to hold the data actually used in cryptography or
|
|
* whatever
|
|
*/
|
|
union {
|
|
unsigned long value;
|
|
void *data;
|
|
struct keyring_list *subscriptions;
|
|
} payload;
|
|
};
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* kernel managed key type definition
|
|
*/
|
|
struct key_type {
|
|
/* name of the type */
|
|
const char *name;
|
|
|
|
/* default payload length for quota precalculation (optional)
|
|
* - this can be used instead of calling key_payload_reserve(), that
|
|
* function only needs to be called if the real datalen is different
|
|
*/
|
|
size_t def_datalen;
|
|
|
|
/* instantiate a key of this type
|
|
* - this method should call key_payload_reserve() to determine if the
|
|
* user's quota will hold the payload
|
|
*/
|
|
int (*instantiate)(struct key *key, const void *data, size_t datalen);
|
|
|
|
/* duplicate a key of this type (optional)
|
|
* - the source key will be locked against change
|
|
* - the new description will be attached
|
|
* - the quota will have been adjusted automatically from
|
|
* source->quotalen
|
|
*/
|
|
int (*duplicate)(struct key *key, const struct key *source);
|
|
|
|
/* update a key of this type (optional)
|
|
* - this method should call key_payload_reserve() to recalculate the
|
|
* quota consumption
|
|
* - the key must be locked against read when modifying
|
|
*/
|
|
int (*update)(struct key *key, const void *data, size_t datalen);
|
|
|
|
/* match a key against a description */
|
|
int (*match)(const struct key *key, const void *desc);
|
|
|
|
/* clear the data from a key (optional) */
|
|
void (*destroy)(struct key *key);
|
|
|
|
/* describe a key */
|
|
void (*describe)(const struct key *key, struct seq_file *p);
|
|
|
|
/* read a key's data (optional)
|
|
* - permission checks will be done by the caller
|
|
* - the key's semaphore will be readlocked by the caller
|
|
* - should return the amount of data that could be read, no matter how
|
|
* much is copied into the buffer
|
|
* - shouldn't do the copy if the buffer is NULL
|
|
*/
|
|
long (*read)(const struct key *key, char __user *buffer, size_t buflen);
|
|
|
|
/* internal fields */
|
|
struct list_head link; /* link in types list */
|
|
};
|
|
|
|
extern struct key_type key_type_keyring;
|
|
|
|
extern int register_key_type(struct key_type *ktype);
|
|
extern void unregister_key_type(struct key_type *ktype);
|
|
|
|
extern struct key *key_alloc(struct key_type *type,
|
|
const char *desc,
|
|
uid_t uid, gid_t gid, key_perm_t perm,
|
|
int not_in_quota);
|
|
extern int key_payload_reserve(struct key *key, size_t datalen);
|
|
extern int key_instantiate_and_link(struct key *key,
|
|
const void *data,
|
|
size_t datalen,
|
|
struct key *keyring,
|
|
struct key *instkey);
|
|
extern int key_negate_and_link(struct key *key,
|
|
unsigned timeout,
|
|
struct key *keyring,
|
|
struct key *instkey);
|
|
extern void key_revoke(struct key *key);
|
|
extern void key_put(struct key *key);
|
|
|
|
static inline struct key *key_get(struct key *key)
|
|
{
|
|
if (key)
|
|
atomic_inc(&key->usage);
|
|
return key;
|
|
}
|
|
|
|
static inline void key_ref_put(key_ref_t key_ref)
|
|
{
|
|
key_put(key_ref_to_ptr(key_ref));
|
|
}
|
|
|
|
extern struct key *request_key(struct key_type *type,
|
|
const char *description,
|
|
const char *callout_info);
|
|
|
|
extern int key_validate(struct key *key);
|
|
|
|
extern key_ref_t key_create_or_update(key_ref_t keyring,
|
|
const char *type,
|
|
const char *description,
|
|
const void *payload,
|
|
size_t plen,
|
|
int not_in_quota);
|
|
|
|
extern int key_update(key_ref_t key,
|
|
const void *payload,
|
|
size_t plen);
|
|
|
|
extern int key_link(struct key *keyring,
|
|
struct key *key);
|
|
|
|
extern int key_unlink(struct key *keyring,
|
|
struct key *key);
|
|
|
|
extern struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
|
|
int not_in_quota, struct key *dest);
|
|
|
|
extern int keyring_clear(struct key *keyring);
|
|
|
|
extern key_ref_t keyring_search(key_ref_t keyring,
|
|
struct key_type *type,
|
|
const char *description);
|
|
|
|
extern int keyring_add_key(struct key *keyring,
|
|
struct key *key);
|
|
|
|
extern struct key *key_lookup(key_serial_t id);
|
|
|
|
extern void keyring_replace_payload(struct key *key, void *replacement);
|
|
|
|
#define key_serial(key) ((key) ? (key)->serial : 0)
|
|
|
|
/*
|
|
* the userspace interface
|
|
*/
|
|
extern struct key root_user_keyring, root_session_keyring;
|
|
extern int alloc_uid_keyring(struct user_struct *user);
|
|
extern void switch_uid_keyring(struct user_struct *new_user);
|
|
extern int copy_keys(unsigned long clone_flags, struct task_struct *tsk);
|
|
extern int copy_thread_group_keys(struct task_struct *tsk);
|
|
extern void exit_keys(struct task_struct *tsk);
|
|
extern void exit_thread_group_keys(struct signal_struct *tg);
|
|
extern int suid_keys(struct task_struct *tsk);
|
|
extern int exec_keys(struct task_struct *tsk);
|
|
extern void key_fsuid_changed(struct task_struct *tsk);
|
|
extern void key_fsgid_changed(struct task_struct *tsk);
|
|
extern void key_init(void);
|
|
|
|
#define __install_session_keyring(tsk, keyring) \
|
|
({ \
|
|
struct key *old_session = tsk->signal->session_keyring; \
|
|
tsk->signal->session_keyring = keyring; \
|
|
old_session; \
|
|
})
|
|
|
|
#else /* CONFIG_KEYS */
|
|
|
|
#define key_validate(k) 0
|
|
#define key_serial(k) 0
|
|
#define key_get(k) ({ NULL; })
|
|
#define key_put(k) do { } while(0)
|
|
#define key_ref_put(k) do { } while(0)
|
|
#define make_key_ref(k) ({ NULL; })
|
|
#define key_ref_to_ptr(k) ({ NULL; })
|
|
#define is_key_possessed(k) 0
|
|
#define alloc_uid_keyring(u) 0
|
|
#define switch_uid_keyring(u) do { } while(0)
|
|
#define __install_session_keyring(t, k) ({ NULL; })
|
|
#define copy_keys(f,t) 0
|
|
#define copy_thread_group_keys(t) 0
|
|
#define exit_keys(t) do { } while(0)
|
|
#define exit_thread_group_keys(tg) do { } while(0)
|
|
#define suid_keys(t) do { } while(0)
|
|
#define exec_keys(t) do { } while(0)
|
|
#define key_fsuid_changed(t) do { } while(0)
|
|
#define key_fsgid_changed(t) do { } while(0)
|
|
#define key_init() do { } while(0)
|
|
|
|
#endif /* CONFIG_KEYS */
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _LINUX_KEY_H */
|