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/wait_bit.h> 17 #include <linux/cred.h> 18 #include <linux/key-type.h> 19 #include <linux/task_work.h> 20 #include <linux/keyctl.h> 21 #include <linux/refcount.h> 22 #include <linux/compat.h> 23 24 struct iovec; 25 26 #ifdef __KDEBUG 27 #define kenter(FMT, ...) \ 28 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 29 #define kleave(FMT, ...) \ 30 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 31 #define kdebug(FMT, ...) \ 32 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__) 33 #else 34 #define kenter(FMT, ...) \ 35 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 36 #define kleave(FMT, ...) \ 37 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 38 #define kdebug(FMT, ...) \ 39 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__) 40 #endif 41 42 extern struct key_type key_type_dead; 43 extern struct key_type key_type_user; 44 extern struct key_type key_type_logon; 45 46 /*****************************************************************************/ 47 /* 48 * Keep track of keys for a user. 49 * 50 * This needs to be separate to user_struct to avoid a refcount-loop 51 * (user_struct pins some keyrings which pin this struct). 52 * 53 * We also keep track of keys under request from userspace for this UID here. 54 */ 55 struct key_user { 56 struct rb_node node; 57 struct mutex cons_lock; /* construction initiation lock */ 58 spinlock_t lock; 59 refcount_t usage; /* for accessing qnkeys & qnbytes */ 60 atomic_t nkeys; /* number of keys */ 61 atomic_t nikeys; /* number of instantiated keys */ 62 kuid_t uid; 63 int qnkeys; /* number of keys allocated to this user */ 64 int qnbytes; /* number of bytes allocated to this user */ 65 }; 66 67 extern struct rb_root key_user_tree; 68 extern spinlock_t key_user_lock; 69 extern struct key_user root_key_user; 70 71 extern struct key_user *key_user_lookup(kuid_t uid); 72 extern void key_user_put(struct key_user *user); 73 74 /* 75 * Key quota limits. 76 * - root has its own separate limits to everyone else 77 */ 78 extern unsigned key_quota_root_maxkeys; 79 extern unsigned key_quota_root_maxbytes; 80 extern unsigned key_quota_maxkeys; 81 extern unsigned key_quota_maxbytes; 82 83 #define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */ 84 85 86 extern struct kmem_cache *key_jar; 87 extern struct rb_root key_serial_tree; 88 extern spinlock_t key_serial_lock; 89 extern struct mutex key_construction_mutex; 90 extern wait_queue_head_t request_key_conswq; 91 92 93 extern struct key_type *key_type_lookup(const char *type); 94 extern void key_type_put(struct key_type *ktype); 95 96 extern int __key_link_begin(struct key *keyring, 97 const struct keyring_index_key *index_key, 98 struct assoc_array_edit **_edit); 99 extern int __key_link_check_live_key(struct key *keyring, struct key *key); 100 extern void __key_link(struct key *key, struct assoc_array_edit **_edit); 101 extern void __key_link_end(struct key *keyring, 102 const struct keyring_index_key *index_key, 103 struct assoc_array_edit *edit); 104 105 extern key_ref_t find_key_to_update(key_ref_t keyring_ref, 106 const struct keyring_index_key *index_key); 107 108 extern struct key *keyring_search_instkey(struct key *keyring, 109 key_serial_t target_id); 110 111 extern int iterate_over_keyring(const struct key *keyring, 112 int (*func)(const struct key *key, void *data), 113 void *data); 114 115 struct keyring_search_context { 116 struct keyring_index_key index_key; 117 const struct cred *cred; 118 struct key_match_data match_data; 119 unsigned flags; 120 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */ 121 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */ 122 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */ 123 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */ 124 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */ 125 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */ 126 127 int (*iterator)(const void *object, void *iterator_data); 128 129 /* Internal stuff */ 130 int skipped_ret; 131 bool possessed; 132 key_ref_t result; 133 struct timespec now; 134 }; 135 136 extern bool key_default_cmp(const struct key *key, 137 const struct key_match_data *match_data); 138 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 139 struct keyring_search_context *ctx); 140 141 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); 142 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); 143 144 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 145 146 extern int install_user_keyrings(void); 147 extern int install_thread_keyring_to_cred(struct cred *); 148 extern int install_process_keyring_to_cred(struct cred *); 149 extern int install_session_keyring_to_cred(struct cred *, struct key *); 150 151 extern struct key *request_key_and_link(struct key_type *type, 152 const char *description, 153 const void *callout_info, 154 size_t callout_len, 155 void *aux, 156 struct key *dest_keyring, 157 unsigned long flags); 158 159 extern bool lookup_user_key_possessed(const struct key *key, 160 const struct key_match_data *match_data); 161 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 162 key_perm_t perm); 163 #define KEY_LOOKUP_CREATE 0x01 164 #define KEY_LOOKUP_PARTIAL 0x02 165 #define KEY_LOOKUP_FOR_UNLINK 0x04 166 167 extern long join_session_keyring(const char *name); 168 extern void key_change_session_keyring(struct callback_head *twork); 169 170 extern struct work_struct key_gc_work; 171 extern unsigned key_gc_delay; 172 extern void keyring_gc(struct key *keyring, time_t limit); 173 extern void keyring_restriction_gc(struct key *keyring, 174 struct key_type *dead_type); 175 extern void key_schedule_gc(time_t gc_at); 176 extern void key_schedule_gc_links(void); 177 extern void key_gc_keytype(struct key_type *ktype); 178 179 extern int key_task_permission(const key_ref_t key_ref, 180 const struct cred *cred, 181 key_perm_t perm); 182 183 /* 184 * Check to see whether permission is granted to use a key in the desired way. 185 */ 186 static inline int key_permission(const key_ref_t key_ref, unsigned perm) 187 { 188 return key_task_permission(key_ref, current_cred(), perm); 189 } 190 191 /* 192 * Authorisation record for request_key(). 193 */ 194 struct request_key_auth { 195 struct key *target_key; 196 struct key *dest_keyring; 197 const struct cred *cred; 198 void *callout_info; 199 size_t callout_len; 200 pid_t pid; 201 }; 202 203 extern struct key_type key_type_request_key_auth; 204 extern struct key *request_key_auth_new(struct key *target, 205 const void *callout_info, 206 size_t callout_len, 207 struct key *dest_keyring); 208 209 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 210 211 /* 212 * Determine whether a key is dead. 213 */ 214 static inline bool key_is_dead(const struct key *key, time_t limit) 215 { 216 return 217 key->flags & ((1 << KEY_FLAG_DEAD) | 218 (1 << KEY_FLAG_INVALIDATED)) || 219 (key->expiry > 0 && key->expiry <= limit); 220 } 221 222 /* 223 * keyctl() functions 224 */ 225 extern long keyctl_get_keyring_ID(key_serial_t, int); 226 extern long keyctl_join_session_keyring(const char __user *); 227 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 228 extern long keyctl_revoke_key(key_serial_t); 229 extern long keyctl_keyring_clear(key_serial_t); 230 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 231 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 232 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 233 extern long keyctl_keyring_search(key_serial_t, const char __user *, 234 const char __user *, key_serial_t); 235 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 236 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 237 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 238 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 239 size_t, key_serial_t); 240 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 241 extern long keyctl_set_reqkey_keyring(int); 242 extern long keyctl_set_timeout(key_serial_t, unsigned); 243 extern long keyctl_assume_authority(key_serial_t); 244 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 245 size_t buflen); 246 extern long keyctl_session_to_parent(void); 247 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 248 extern long keyctl_instantiate_key_iov(key_serial_t, 249 const struct iovec __user *, 250 unsigned, key_serial_t); 251 extern long keyctl_invalidate_key(key_serial_t); 252 253 struct iov_iter; 254 extern long keyctl_instantiate_key_common(key_serial_t, 255 struct iov_iter *, 256 key_serial_t); 257 extern long keyctl_restrict_keyring(key_serial_t id, 258 const char __user *_type, 259 const char __user *_restriction); 260 #ifdef CONFIG_PERSISTENT_KEYRINGS 261 extern long keyctl_get_persistent(uid_t, key_serial_t); 262 extern unsigned persistent_keyring_expiry; 263 #else 264 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring) 265 { 266 return -EOPNOTSUPP; 267 } 268 #endif 269 270 #ifdef CONFIG_KEY_DH_OPERATIONS 271 extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *, 272 size_t, struct keyctl_kdf_params __user *); 273 extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *, 274 size_t, struct keyctl_kdf_params *); 275 #ifdef CONFIG_KEYS_COMPAT 276 extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params, 277 char __user *buffer, size_t buflen, 278 struct compat_keyctl_kdf_params __user *kdf); 279 #endif 280 #define KEYCTL_KDF_MAX_OUTPUT_LEN 1024 /* max length of KDF output */ 281 #define KEYCTL_KDF_MAX_OI_LEN 64 /* max length of otherinfo */ 282 #else 283 static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params, 284 char __user *buffer, size_t buflen, 285 struct keyctl_kdf_params __user *kdf) 286 { 287 return -EOPNOTSUPP; 288 } 289 290 #ifdef CONFIG_KEYS_COMPAT 291 static inline long compat_keyctl_dh_compute( 292 struct keyctl_dh_params __user *params, 293 char __user *buffer, size_t buflen, 294 struct keyctl_kdf_params __user *kdf) 295 { 296 return -EOPNOTSUPP; 297 } 298 #endif 299 #endif 300 301 /* 302 * Debugging key validation 303 */ 304 #ifdef KEY_DEBUGGING 305 extern void __key_check(const struct key *); 306 307 static inline void key_check(const struct key *key) 308 { 309 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 310 __key_check(key); 311 } 312 313 #else 314 315 #define key_check(key) do {} while(0) 316 317 #endif 318 319 #endif /* _INTERNAL_H */ 320