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