-/* key.h: authentication token and access key management
+/* Authentication token and access key management
*
- * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2004, 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
#include <linux/list.h>
#include <linux/rbtree.h>
#include <linux/rcupdate.h>
+#include <linux/sysctl.h>
+#include <linux/rwsem.h>
#include <asm/atomic.h>
#ifdef __KERNEL__
#undef KEY_DEBUGGING
-#define KEY_USR_VIEW 0x00010000 /* user can view a key's attributes */
-#define KEY_USR_READ 0x00020000 /* user can read key payload / view keyring */
-#define KEY_USR_WRITE 0x00040000 /* user can update key payload / add link to keyring */
-#define KEY_USR_SEARCH 0x00080000 /* user can find a key in search / search a keyring */
-#define KEY_USR_LINK 0x00100000 /* user can create a link to a key/keyring */
-#define KEY_USR_ALL 0x001f0000
+#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_ALL 0x00001f00
+#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_ALL 0x0000001f
+#define KEY_OTH_SETATTR 0x00000020
+#define KEY_OTH_ALL 0x0000003f
+
+#define KEY_PERM_UNDEF 0xffffffff
struct seq_file;
struct user_struct;
struct signal_struct;
+struct cred;
struct key_type;
struct key_owner;
/*****************************************************************************/
/*
+ * 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
struct key_type *type; /* type of key */
struct rw_semaphore sem; /* change vs change sem */
struct key_user *user; /* owner of this key */
- time_t expiry; /* time at which key expires (or 0) */
+ void *security; /* security data for this key */
+ union {
+ time_t expiry; /* time at which key expires (or 0) */
+ time_t revoked_at; /* time at which key was revoked */
+ };
uid_t uid;
gid_t gid;
key_perm_t perm; /* access permissions */
*/
union {
struct list_head link;
+ unsigned long x[2];
+ void *p[2];
} type_data;
/* key data
} 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 *key_alloc(struct key_type *type,
+ const char *desc,
+ uid_t uid, gid_t gid,
+ const struct cred *cred,
+ key_perm_t perm,
+ unsigned long flags);
-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);
+#define KEY_ALLOC_IN_QUOTA 0x0000 /* add to quota, reject if would overrun */
+#define KEY_ALLOC_QUOTA_OVERRUN 0x0001 /* add to quota, permit even if overrun */
+#define KEY_ALLOC_NOT_IN_QUOTA 0x0002 /* not in quota */
-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);
-extern int key_negate_and_link(struct key *key,
- unsigned timeout,
- struct key *keyring);
extern void key_revoke(struct key *key);
extern void key_put(struct key *key);
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 struct key *request_key_with_auxdata(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux);
+
+extern struct key *request_key_async(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len);
+
+extern struct key *request_key_async_with_auxdata(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux);
+
+extern int wait_for_key_construction(struct key *key, bool intr);
+
extern int key_validate(struct key *key);
-extern struct key *key_create_or_update(struct key *keyring,
- const char *type,
- const char *description,
- const void *payload,
- size_t plen,
- int not_in_quota);
+extern key_ref_t key_create_or_update(key_ref_t keyring,
+ const char *type,
+ const char *description,
+ const void *payload,
+ size_t plen,
+ key_perm_t perm,
+ unsigned long flags);
-extern int key_update(struct key *key,
+extern int key_update(key_ref_t key,
const void *payload,
size_t plen);
struct key *key);
extern struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
- int not_in_quota, struct key *dest);
+ const struct cred *cred,
+ unsigned long flags,
+ struct key *dest);
extern int keyring_clear(struct key *keyring);
-extern struct key *keyring_search(struct key *keyring,
- struct key_type *type,
- const char *description);
-
-extern struct key *search_process_keyrings(struct key_type *type,
- const char *description);
+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);
+static inline key_serial_t key_serial(struct key *key)
+{
+ return key ? key->serial : 0;
+}
+
+#ifdef CONFIG_SYSCTL
+extern ctl_table key_sysctls[];
+#endif
-#define key_serial(key) ((key) ? (key)->serial : 0)
+extern void key_replace_session_keyring(void);
/*
* 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 int install_thread_keyring_to_cred(struct cred *cred);
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_revoke(k) do { } while(0)
#define key_put(k) do { } while(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_ref_put(k) do { } while(0)
+#define make_key_ref(k, p) NULL
+#define key_ref_to_ptr(k) NULL
+#define is_key_possessed(k) 0
#define key_fsuid_changed(t) do { } while(0)
#define key_fsgid_changed(t) do { } while(0)
#define key_init() do { } while(0)
+#define key_replace_session_keyring() do { } while(0)
#endif /* CONFIG_KEYS */
#endif /* __KERNEL__ */