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 struct iovec; 20 21 #ifdef __KDEBUG 22 #define kenter(FMT, ...) \ 23 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 24 #define kleave(FMT, ...) \ 25 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 26 #define kdebug(FMT, ...) \ 27 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__) 28 #else 29 #define kenter(FMT, ...) \ 30 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 31 #define kleave(FMT, ...) \ 32 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 33 #define kdebug(FMT, ...) \ 34 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__) 35 #endif 36 37 extern struct key_type key_type_dead; 38 extern struct key_type key_type_user; 39 extern struct key_type key_type_logon; 40 41 /*****************************************************************************/ 42 /* 43 * Keep track of keys for a user. 44 * 45 * This needs to be separate to user_struct to avoid a refcount-loop 46 * (user_struct pins some keyrings which pin this struct). 47 * 48 * We also keep track of keys under request from userspace for this UID here. 49 */ 50 struct key_user { 51 struct rb_node node; 52 struct mutex cons_lock; /* construction initiation lock */ 53 spinlock_t lock; 54 atomic_t usage; /* for accessing qnkeys & qnbytes */ 55 atomic_t nkeys; /* number of keys */ 56 atomic_t nikeys; /* number of instantiated keys */ 57 kuid_t uid; 58 int qnkeys; /* number of keys allocated to this user */ 59 int qnbytes; /* number of bytes allocated to this user */ 60 }; 61 62 extern struct rb_root key_user_tree; 63 extern spinlock_t key_user_lock; 64 extern struct key_user root_key_user; 65 66 extern struct key_user *key_user_lookup(kuid_t uid); 67 extern void key_user_put(struct key_user *user); 68 69 /* 70 * Key quota limits. 71 * - root has its own separate limits to everyone else 72 */ 73 extern unsigned key_quota_root_maxkeys; 74 extern unsigned key_quota_root_maxbytes; 75 extern unsigned key_quota_maxkeys; 76 extern unsigned key_quota_maxbytes; 77 78 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */ 79 80 81 extern struct kmem_cache *key_jar; 82 extern struct rb_root key_serial_tree; 83 extern spinlock_t key_serial_lock; 84 extern struct mutex key_construction_mutex; 85 extern wait_queue_head_t request_key_conswq; 86 87 88 extern struct key_type *key_type_lookup(const char *type); 89 extern void key_type_put(struct key_type *ktype); 90 91 extern int __key_link_begin(struct key *keyring, 92 const struct keyring_index_key *index_key, 93 struct assoc_array_edit **_edit); 94 extern int __key_link_check_live_key(struct key *keyring, struct key *key); 95 extern void __key_link(struct key *key, struct assoc_array_edit **_edit); 96 extern void __key_link_end(struct key *keyring, 97 const struct keyring_index_key *index_key, 98 struct assoc_array_edit *edit); 99 100 extern key_ref_t find_key_to_update(key_ref_t keyring_ref, 101 const struct keyring_index_key *index_key); 102 103 extern struct key *keyring_search_instkey(struct key *keyring, 104 key_serial_t target_id); 105 106 extern int iterate_over_keyring(const struct key *keyring, 107 int (*func)(const struct key *key, void *data), 108 void *data); 109 110 typedef int (*key_match_func_t)(const struct key *, const void *); 111 112 struct keyring_search_context { 113 struct keyring_index_key index_key; 114 const struct cred *cred; 115 key_match_func_t match; 116 const void *match_data; 117 unsigned flags; 118 #define KEYRING_SEARCH_LOOKUP_TYPE 0x0001 /* [as type->def_lookup_type] */ 119 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0002 /* Skip state checks */ 120 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0004 /* Override NO_STATE_CHECK */ 121 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0008 /* Don't update times */ 122 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0010 /* Don't check permissions */ 123 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0020 /* Give an error on excessive depth */ 124 125 int (*iterator)(const void *object, void *iterator_data); 126 127 /* Internal stuff */ 128 int skipped_ret; 129 bool possessed; 130 key_ref_t result; 131 struct timespec now; 132 }; 133 134 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 135 struct keyring_search_context *ctx); 136 137 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); 138 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); 139 140 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 141 142 extern int install_user_keyrings(void); 143 extern int install_thread_keyring_to_cred(struct cred *); 144 extern int install_process_keyring_to_cred(struct cred *); 145 extern int install_session_keyring_to_cred(struct cred *, struct key *); 146 147 extern struct key *request_key_and_link(struct key_type *type, 148 const char *description, 149 const void *callout_info, 150 size_t callout_len, 151 void *aux, 152 struct key *dest_keyring, 153 unsigned long flags); 154 155 extern int lookup_user_key_possessed(const struct key *key, const void *target); 156 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 157 key_perm_t perm); 158 #define KEY_LOOKUP_CREATE 0x01 159 #define KEY_LOOKUP_PARTIAL 0x02 160 #define KEY_LOOKUP_FOR_UNLINK 0x04 161 162 extern long join_session_keyring(const char *name); 163 extern void key_change_session_keyring(struct callback_head *twork); 164 165 extern struct work_struct key_gc_work; 166 extern unsigned key_gc_delay; 167 extern void keyring_gc(struct key *keyring, time_t limit); 168 extern void key_schedule_gc(time_t gc_at); 169 extern void key_schedule_gc_links(void); 170 extern void key_gc_keytype(struct key_type *ktype); 171 172 extern int key_task_permission(const key_ref_t key_ref, 173 const struct cred *cred, 174 key_perm_t perm); 175 176 /* 177 * Check to see whether permission is granted to use a key in the desired way. 178 */ 179 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm) 180 { 181 return key_task_permission(key_ref, current_cred(), perm); 182 } 183 184 /* required permissions */ 185 #define KEY_VIEW 0x01 /* require permission to view attributes */ 186 #define KEY_READ 0x02 /* require permission to read content */ 187 #define KEY_WRITE 0x04 /* require permission to update / modify */ 188 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */ 189 #define KEY_LINK 0x10 /* require permission to link */ 190 #define KEY_SETATTR 0x20 /* require permission to change attributes */ 191 #define KEY_ALL 0x3f /* all the above permissions */ 192 193 /* 194 * Authorisation record for request_key(). 195 */ 196 struct request_key_auth { 197 struct key *target_key; 198 struct key *dest_keyring; 199 const struct cred *cred; 200 void *callout_info; 201 size_t callout_len; 202 pid_t pid; 203 }; 204 205 extern struct key_type key_type_request_key_auth; 206 extern struct key *request_key_auth_new(struct key *target, 207 const void *callout_info, 208 size_t callout_len, 209 struct key *dest_keyring); 210 211 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 212 213 /* 214 * Determine whether a key is dead. 215 */ 216 static inline bool key_is_dead(const struct key *key, time_t limit) 217 { 218 return 219 key->flags & ((1 << KEY_FLAG_DEAD) | 220 (1 << KEY_FLAG_INVALIDATED)) || 221 (key->expiry > 0 && key->expiry <= limit); 222 } 223 224 /* 225 * keyctl() functions 226 */ 227 extern long keyctl_get_keyring_ID(key_serial_t, int); 228 extern long keyctl_join_session_keyring(const char __user *); 229 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 230 extern long keyctl_revoke_key(key_serial_t); 231 extern long keyctl_keyring_clear(key_serial_t); 232 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 233 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 234 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 235 extern long keyctl_keyring_search(key_serial_t, const char __user *, 236 const char __user *, key_serial_t); 237 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 238 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 239 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 240 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 241 size_t, key_serial_t); 242 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 243 extern long keyctl_set_reqkey_keyring(int); 244 extern long keyctl_set_timeout(key_serial_t, unsigned); 245 extern long keyctl_assume_authority(key_serial_t); 246 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 247 size_t buflen); 248 extern long keyctl_session_to_parent(void); 249 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 250 extern long keyctl_instantiate_key_iov(key_serial_t, 251 const struct iovec __user *, 252 unsigned, key_serial_t); 253 extern long keyctl_invalidate_key(key_serial_t); 254 255 extern long keyctl_instantiate_key_common(key_serial_t, 256 const struct iovec *, 257 unsigned, size_t, key_serial_t); 258 #ifdef CONFIG_PERSISTENT_KEYRINGS 259 extern long keyctl_get_persistent(uid_t, key_serial_t); 260 extern unsigned persistent_keyring_expiry; 261 #else 262 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring) 263 { 264 return -EOPNOTSUPP; 265 } 266 #endif 267 268 /* 269 * Debugging key validation 270 */ 271 #ifdef KEY_DEBUGGING 272 extern void __key_check(const struct key *); 273 274 static inline void key_check(const struct key *key) 275 { 276 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 277 __key_check(key); 278 } 279 280 #else 281 282 #define key_check(key) do {} while(0) 283 284 #endif 285 286 #endif /* _INTERNAL_H */ 287