LXR linux/security/keys/internal.h

   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
  18static inline __attribute__((format(printf, 1, 2)))
  19void 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
  39extern 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 */
  48struct 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
  60extern struct rb_root   key_user_tree;
  61extern spinlock_t       key_user_lock;
  62extern struct key_user  root_key_user;
  63
  64extern struct key_user *key_user_lookup(uid_t uid);
  65extern 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 */
  71extern unsigned key_quota_root_maxkeys;
  72extern unsigned key_quota_root_maxbytes;
  73extern unsigned key_quota_maxkeys;
  74extern unsigned key_quota_maxbytes;
  75
  76#define KEYQUOTA_LINK_BYTES     4               /* a link in a keyring is worth 4 bytes */
  77
  78
  79extern struct rb_root key_serial_tree;
  80extern spinlock_t key_serial_lock;
  81extern struct mutex key_construction_mutex;
  82extern wait_queue_head_t request_key_conswq;
  83
  84
  85extern int __key_link(struct key *keyring, struct key *key);
  86
  87extern 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
  92extern struct key *keyring_search_instkey(struct key *keyring,
  93                                          key_serial_t target_id);
  94
  95typedef int (*key_match_func_t)(const struct key *, const void *);
  96
  97extern 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
 103extern 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
 108extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
 109
 110extern int install_user_keyrings(struct task_struct *tsk);
 111extern int install_thread_keyring(struct task_struct *tsk);
 112extern int install_process_keyring(struct task_struct *tsk);
 113
 114extern struct key *request_key_and_link(struct key_type *type,
 115                                        const char *description,
 116                                        const void *callout_info,
 117                                        size_t callout_len,
 118                                        void *aux,
 119                                        struct key *dest_keyring,
 120                                        unsigned long flags);
 121
 122/*
 123 * request_key authorisation
 124 */
 125struct request_key_auth {
 126        struct key              *target_key;
 127        struct task_struct      *context;
 128        void                    *callout_info;
 129        size_t                  callout_len;
 130        pid_t                   pid;
 131};
 132
 133extern struct key_type key_type_request_key_auth;
 134extern struct key *request_key_auth_new(struct key *target,
 135                                        const void *callout_info,
 136                                        size_t callout_len);
 137
 138extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
 139
 140/*
 141 * keyctl functions
 142 */
 143extern long keyctl_get_keyring_ID(key_serial_t, int);
 144extern long keyctl_join_session_keyring(const char __user *);
 145extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
 146extern long keyctl_revoke_key(key_serial_t);
 147extern long keyctl_keyring_clear(key_serial_t);
 148extern long keyctl_keyring_link(key_serial_t, key_serial_t);
 149extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
 150extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
 151extern long keyctl_keyring_search(key_serial_t, const char __user *,
 152                                  const char __user *, key_serial_t);
 153extern long keyctl_read_key(key_serial_t, char __user *, size_t);
 154extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
 155extern long keyctl_setperm_key(key_serial_t, key_perm_t);
 156extern long keyctl_instantiate_key(key_serial_t, const void __user *,
 157                                   size_t, key_serial_t);
 158extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
 159extern long keyctl_set_reqkey_keyring(int);
 160extern long keyctl_set_timeout(key_serial_t, unsigned);
 161extern long keyctl_assume_authority(key_serial_t);
 162extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
 163                                size_t buflen);
 164
 165/*
 166 * debugging key validation
 167 */
 168#ifdef KEY_DEBUGGING
 169extern void __key_check(const struct key *);
 170
 171static inline void key_check(const struct key *key)
 172{
 173        if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
 174                __key_check(key);
 175}
 176
 177#else
 178
 179#define key_check(key) do {} while(0)
 180
 181#endif
 182
 183#endif /* _INTERNAL_H */
 184