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/cred.h> 17 #include <linux/key-type.h> 18 #include <linux/task_work.h> 19 #include <linux/keyctl.h> 20 #include <linux/refcount.h> 21 #include <linux/compat.h> 22 23 struct iovec; 24 25 #ifdef __KDEBUG 26 #define kenter(FMT, ...) \ 27 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 28 #define kleave(FMT, ...) \ 29 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 30 #define kdebug(FMT, ...) \ 31 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__) 32 #else 33 #define kenter(FMT, ...) \ 34 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 35 #define kleave(FMT, ...) \ 36 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 37 #define kdebug(FMT, ...) \ 38 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__) 39 #endif 40 41 extern struct key_type key_type_dead; 42 extern struct key_type key_type_user; 43 extern struct key_type key_type_logon; 44 45 /*****************************************************************************/ 46 /* 47 * Keep track of keys for a user. 48 * 49 * This needs to be separate to user_struct to avoid a refcount-loop 50 * (user_struct pins some keyrings which pin this struct). 51 * 52 * We also keep track of keys under request from userspace for this UID here. 53 */ 54 struct key_user { 55 struct rb_node node; 56 struct mutex cons_lock; /* construction initiation lock */ 57 spinlock_t lock; 58 refcount_t usage; /* for accessing qnkeys & qnbytes */ 59 atomic_t nkeys; /* number of keys */ 60 atomic_t nikeys; /* number of instantiated keys */ 61 kuid_t uid; 62 int qnkeys; /* number of keys allocated to this user */ 63 int qnbytes; /* number of bytes allocated to this user */ 64 }; 65 66 extern struct rb_root key_user_tree; 67 extern spinlock_t key_user_lock; 68 extern struct key_user root_key_user; 69 70 extern struct key_user *key_user_lookup(kuid_t uid); 71 extern void key_user_put(struct key_user *user); 72 73 /* 74 * Key quota limits. 75 * - root has its own separate limits to everyone else 76 */ 77 extern unsigned key_quota_root_maxkeys; 78 extern unsigned key_quota_root_maxbytes; 79 extern unsigned key_quota_maxkeys; 80 extern unsigned key_quota_maxbytes; 81 82 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */ 83 84 85 extern struct kmem_cache *key_jar; 86 extern struct rb_root key_serial_tree; 87 extern spinlock_t key_serial_lock; 88 extern struct mutex key_construction_mutex; 89 extern wait_queue_head_t request_key_conswq; 90 91 92 extern struct key_type *key_type_lookup(const char *type); 93 extern void key_type_put(struct key_type *ktype); 94 95 extern int __key_link_begin(struct key *keyring, 96 const struct keyring_index_key *index_key, 97 struct assoc_array_edit **_edit); 98 extern int __key_link_check_live_key(struct key *keyring, struct key *key); 99 extern void __key_link(struct key *key, struct assoc_array_edit **_edit); 100 extern void __key_link_end(struct key *keyring, 101 const struct keyring_index_key *index_key, 102 struct assoc_array_edit *edit); 103 104 extern key_ref_t find_key_to_update(key_ref_t keyring_ref, 105 const struct keyring_index_key *index_key); 106 107 extern struct key *keyring_search_instkey(struct key *keyring, 108 key_serial_t target_id); 109 110 extern int iterate_over_keyring(const struct key *keyring, 111 int (*func)(const struct key *key, void *data), 112 void *data); 113 114 struct keyring_search_context { 115 struct keyring_index_key index_key; 116 const struct cred *cred; 117 struct key_match_data match_data; 118 unsigned flags; 119 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */ 120 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */ 121 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */ 122 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */ 123 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */ 124 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */ 125 126 int (*iterator)(const void *object, void *iterator_data); 127 128 /* Internal stuff */ 129 int skipped_ret; 130 bool possessed; 131 key_ref_t result; 132 struct timespec now; 133 }; 134 135 extern bool key_default_cmp(const struct key *key, 136 const struct key_match_data *match_data); 137 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 138 struct keyring_search_context *ctx); 139 140 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); 141 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); 142 143 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 144 145 extern int install_user_keyrings(void); 146 extern int install_thread_keyring_to_cred(struct cred *); 147 extern int install_process_keyring_to_cred(struct cred *); 148 extern int install_session_keyring_to_cred(struct cred *, struct key *); 149 150 extern struct key *request_key_and_link(struct key_type *type, 151 const char *description, 152 const void *callout_info, 153 size_t callout_len, 154 void *aux, 155 struct key *dest_keyring, 156 unsigned long flags); 157 158 extern bool lookup_user_key_possessed(const struct key *key, 159 const struct key_match_data *match_data); 160 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 161 key_perm_t perm); 162 #define KEY_LOOKUP_CREATE 0x01 163 #define KEY_LOOKUP_PARTIAL 0x02 164 #define KEY_LOOKUP_FOR_UNLINK 0x04 165 166 extern long join_session_keyring(const char *name); 167 extern void key_change_session_keyring(struct callback_head *twork); 168 169 extern struct work_struct key_gc_work; 170 extern unsigned key_gc_delay; 171 extern void keyring_gc(struct key *keyring, time_t limit); 172 extern void keyring_restriction_gc(struct key *keyring, 173 struct key_type *dead_type); 174 extern void key_schedule_gc(time_t gc_at); 175 extern void key_schedule_gc_links(void); 176 extern void key_gc_keytype(struct key_type *ktype); 177 178 extern int key_task_permission(const key_ref_t key_ref, 179 const struct cred *cred, 180 key_perm_t perm); 181 182 /* 183 * Check to see whether permission is granted to use a key in the desired way. 184 */ 185 static inline int key_permission(const key_ref_t key_ref, unsigned perm) 186 { 187 return key_task_permission(key_ref, current_cred(), perm); 188 } 189 190 /* 191 * Authorisation record for request_key(). 192 */ 193 struct request_key_auth { 194 struct key *target_key; 195 struct key *dest_keyring; 196 const struct cred *cred; 197 void *callout_info; 198 size_t callout_len; 199 pid_t pid; 200 }; 201 202 extern struct key_type key_type_request_key_auth; 203 extern struct key *request_key_auth_new(struct key *target, 204 const void *callout_info, 205 size_t callout_len, 206 struct key *dest_keyring); 207 208 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 209 210 /* 211 * Determine whether a key is dead. 212 */ 213 static inline bool key_is_dead(const struct key *key, time_t limit) 214 { 215 return 216 key->flags & ((1 << KEY_FLAG_DEAD) | 217 (1 << KEY_FLAG_INVALIDATED)) || 218 (key->expiry > 0 && key->expiry <= limit); 219 } 220 221 /* 222 * keyctl() functions 223 */ 224 extern long keyctl_get_keyring_ID(key_serial_t, int); 225 extern long keyctl_join_session_keyring(const char __user *); 226 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 227 extern long keyctl_revoke_key(key_serial_t); 228 extern long keyctl_keyring_clear(key_serial_t); 229 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 230 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 231 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 232 extern long keyctl_keyring_search(key_serial_t, const char __user *, 233 const char __user *, key_serial_t); 234 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 235 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 236 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 237 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 238 size_t, key_serial_t); 239 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 240 extern long keyctl_set_reqkey_keyring(int); 241 extern long keyctl_set_timeout(key_serial_t, unsigned); 242 extern long keyctl_assume_authority(key_serial_t); 243 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 244 size_t buflen); 245 extern long keyctl_session_to_parent(void); 246 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 247 extern long keyctl_instantiate_key_iov(key_serial_t, 248 const struct iovec __user *, 249 unsigned, key_serial_t); 250 extern long keyctl_invalidate_key(key_serial_t); 251 252 struct iov_iter; 253 extern long keyctl_instantiate_key_common(key_serial_t, 254 struct iov_iter *, 255 key_serial_t); 256 extern long keyctl_restrict_keyring(key_serial_t id, 257 const char __user *_type, 258 const char __user *_restriction); 259 #ifdef CONFIG_PERSISTENT_KEYRINGS 260 extern long keyctl_get_persistent(uid_t, key_serial_t); 261 extern unsigned persistent_keyring_expiry; 262 #else 263 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring) 264 { 265 return -EOPNOTSUPP; 266 } 267 #endif 268 269 #ifdef CONFIG_KEY_DH_OPERATIONS 270 extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *, 271 size_t, struct keyctl_kdf_params __user *); 272 extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *, 273 size_t, struct keyctl_kdf_params *); 274 #ifdef CONFIG_KEYS_COMPAT 275 extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params, 276 char __user *buffer, size_t buflen, 277 struct compat_keyctl_kdf_params __user *kdf); 278 #endif 279 #define KEYCTL_KDF_MAX_OUTPUT_LEN 1024 /* max length of KDF output */ 280 #define KEYCTL_KDF_MAX_OI_LEN 64 /* max length of otherinfo */ 281 #else 282 static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params, 283 char __user *buffer, size_t buflen, 284 struct keyctl_kdf_params __user *kdf) 285 { 286 return -EOPNOTSUPP; 287 } 288 289 #ifdef CONFIG_KEYS_COMPAT 290 static inline long compat_keyctl_dh_compute( 291 struct keyctl_dh_params __user *params, 292 char __user *buffer, size_t buflen, 293 struct keyctl_kdf_params __user *kdf) 294 { 295 return -EOPNOTSUPP; 296 } 297 #endif 298 #endif 299 300 /* 301 * Debugging key validation 302 */ 303 #ifdef KEY_DEBUGGING 304 extern void __key_check(const struct key *); 305 306 static inline void key_check(const struct key *key) 307 { 308 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 309 __key_check(key); 310 } 311 312 #else 313 314 #define key_check(key) do {} while(0) 315 316 #endif 317 318 #endif /* _INTERNAL_H */ 319