1 /* 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/sched.h> 16 #include <linux/key-type.h> 17 #include <linux/task_work.h> 18 19 #ifdef __KDEBUG 20 #define kenter(FMT, ...) \ 21 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 22 #define kleave(FMT, ...) \ 23 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 24 #define kdebug(FMT, ...) \ 25 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__) 26 #else 27 #define kenter(FMT, ...) \ 28 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 29 #define kleave(FMT, ...) \ 30 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 31 #define kdebug(FMT, ...) \ 32 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__) 33 #endif 34 35 extern struct key_type key_type_dead; 36 extern struct key_type key_type_user; 37 extern struct key_type key_type_logon; 38 39 /*****************************************************************************/ 40 /* 41 * Keep track of keys for a user. 42 * 43 * This needs to be separate to user_struct to avoid a refcount-loop 44 * (user_struct pins some keyrings which pin this struct). 45 * 46 * We also keep track of keys under request from userspace for this UID here. 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 kuid_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(kuid_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 kmem_cache *key_jar; 80 extern struct rb_root key_serial_tree; 81 extern spinlock_t key_serial_lock; 82 extern struct mutex key_construction_mutex; 83 extern wait_queue_head_t request_key_conswq; 84 85 86 extern struct key_type *key_type_lookup(const char *type); 87 extern void key_type_put(struct key_type *ktype); 88 89 extern int __key_link_begin(struct key *keyring, 90 const struct key_type *type, 91 const char *description, 92 unsigned long *_prealloc); 93 extern int __key_link_check_live_key(struct key *keyring, struct key *key); 94 extern void __key_link(struct key *keyring, struct key *key, 95 unsigned long *_prealloc); 96 extern void __key_link_end(struct key *keyring, 97 struct key_type *type, 98 unsigned long prealloc); 99 100 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, 101 const struct key_type *type, 102 const char *description, 103 key_perm_t perm); 104 105 extern struct key *keyring_search_instkey(struct key *keyring, 106 key_serial_t target_id); 107 108 typedef int (*key_match_func_t)(const struct key *, const void *); 109 110 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 111 const struct cred *cred, 112 struct key_type *type, 113 const void *description, 114 key_match_func_t match, 115 bool no_state_check); 116 117 extern key_ref_t search_my_process_keyrings(struct key_type *type, 118 const void *description, 119 key_match_func_t match, 120 bool no_state_check, 121 const struct cred *cred); 122 extern key_ref_t search_process_keyrings(struct key_type *type, 123 const void *description, 124 key_match_func_t match, 125 const struct cred *cred); 126 127 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 128 129 extern int install_user_keyrings(void); 130 extern int install_thread_keyring_to_cred(struct cred *); 131 extern int install_process_keyring_to_cred(struct cred *); 132 extern int install_session_keyring_to_cred(struct cred *, struct key *); 133 134 extern struct key *request_key_and_link(struct key_type *type, 135 const char *description, 136 const void *callout_info, 137 size_t callout_len, 138 void *aux, 139 struct key *dest_keyring, 140 unsigned long flags); 141 142 extern int lookup_user_key_possessed(const struct key *key, const void *target); 143 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 144 key_perm_t perm); 145 #define KEY_LOOKUP_CREATE 0x01 146 #define KEY_LOOKUP_PARTIAL 0x02 147 #define KEY_LOOKUP_FOR_UNLINK 0x04 148 149 extern long join_session_keyring(const char *name); 150 extern void key_change_session_keyring(struct callback_head *twork); 151 152 extern struct work_struct key_gc_work; 153 extern unsigned key_gc_delay; 154 extern void keyring_gc(struct key *keyring, time_t limit); 155 extern void key_schedule_gc(time_t gc_at); 156 extern void key_schedule_gc_links(void); 157 extern void key_gc_keytype(struct key_type *ktype); 158 159 extern int key_task_permission(const key_ref_t key_ref, 160 const struct cred *cred, 161 key_perm_t perm); 162 163 /* 164 * Check to see whether permission is granted to use a key in the desired way. 165 */ 166 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm) 167 { 168 return key_task_permission(key_ref, current_cred(), perm); 169 } 170 171 /* required permissions */ 172 #define KEY_VIEW 0x01 /* require permission to view attributes */ 173 #define KEY_READ 0x02 /* require permission to read content */ 174 #define KEY_WRITE 0x04 /* require permission to update / modify */ 175 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */ 176 #define KEY_LINK 0x10 /* require permission to link */ 177 #define KEY_SETATTR 0x20 /* require permission to change attributes */ 178 #define KEY_ALL 0x3f /* all the above permissions */ 179 180 /* 181 * Authorisation record for request_key(). 182 */ 183 struct request_key_auth { 184 struct key *target_key; 185 struct key *dest_keyring; 186 const struct cred *cred; 187 void *callout_info; 188 size_t callout_len; 189 pid_t pid; 190 }; 191 192 extern struct key_type key_type_request_key_auth; 193 extern struct key *request_key_auth_new(struct key *target, 194 const void *callout_info, 195 size_t callout_len, 196 struct key *dest_keyring); 197 198 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 199 200 /* 201 * Determine whether a key is dead. 202 */ 203 static inline bool key_is_dead(struct key *key, time_t limit) 204 { 205 return 206 key->flags & ((1 << KEY_FLAG_DEAD) | 207 (1 << KEY_FLAG_INVALIDATED)) || 208 (key->expiry > 0 && key->expiry <= limit); 209 } 210 211 /* 212 * keyctl() functions 213 */ 214 extern long keyctl_get_keyring_ID(key_serial_t, int); 215 extern long keyctl_join_session_keyring(const char __user *); 216 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 217 extern long keyctl_revoke_key(key_serial_t); 218 extern long keyctl_keyring_clear(key_serial_t); 219 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 220 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 221 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 222 extern long keyctl_keyring_search(key_serial_t, const char __user *, 223 const char __user *, key_serial_t); 224 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 225 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 226 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 227 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 228 size_t, key_serial_t); 229 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 230 extern long keyctl_set_reqkey_keyring(int); 231 extern long keyctl_set_timeout(key_serial_t, unsigned); 232 extern long keyctl_assume_authority(key_serial_t); 233 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 234 size_t buflen); 235 extern long keyctl_session_to_parent(void); 236 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 237 extern long keyctl_instantiate_key_iov(key_serial_t, 238 const struct iovec __user *, 239 unsigned, key_serial_t); 240 extern long keyctl_invalidate_key(key_serial_t); 241 242 extern long keyctl_instantiate_key_common(key_serial_t, 243 const struct iovec *, 244 unsigned, size_t, key_serial_t); 245 246 /* 247 * Debugging key validation 248 */ 249 #ifdef KEY_DEBUGGING 250 extern void __key_check(const struct key *); 251 252 static inline void key_check(const struct key *key) 253 { 254 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 255 __key_check(key); 256 } 257 258 #else 259 260 #define key_check(key) do {} while(0) 261 262 #endif 263 264 #endif /* _INTERNAL_H */ 265