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 struct keyring_search_context { 111 struct keyring_index_key index_key; 112 const struct cred *cred; 113 struct key_match_data match_data; 114 unsigned flags; 115 #define KEYRING_SEARCH_NO_STATE_CHECK 0x0001 /* Skip state checks */ 116 #define KEYRING_SEARCH_DO_STATE_CHECK 0x0002 /* Override NO_STATE_CHECK */ 117 #define KEYRING_SEARCH_NO_UPDATE_TIME 0x0004 /* Don't update times */ 118 #define KEYRING_SEARCH_NO_CHECK_PERM 0x0008 /* Don't check permissions */ 119 #define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0010 /* Give an error on excessive depth */ 120 #define KEYRING_SEARCH_SKIP_EXPIRED 0x0020 /* Ignore expired keys (intention to replace) */ 121 122 int (*iterator)(const void *object, void *iterator_data); 123 124 /* Internal stuff */ 125 int skipped_ret; 126 bool possessed; 127 key_ref_t result; 128 struct timespec now; 129 }; 130 131 extern bool key_default_cmp(const struct key *key, 132 const struct key_match_data *match_data); 133 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 134 struct keyring_search_context *ctx); 135 136 extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); 137 extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); 138 139 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 140 141 extern int install_user_keyrings(void); 142 extern int install_thread_keyring_to_cred(struct cred *); 143 extern int install_process_keyring_to_cred(struct cred *); 144 extern int install_session_keyring_to_cred(struct cred *, struct key *); 145 146 extern struct key *request_key_and_link(struct key_type *type, 147 const char *description, 148 const void *callout_info, 149 size_t callout_len, 150 void *aux, 151 struct key *dest_keyring, 152 unsigned long flags); 153 154 extern bool lookup_user_key_possessed(const struct key *key, 155 const struct key_match_data *match_data); 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, unsigned perm) 180 { 181 return key_task_permission(key_ref, current_cred(), perm); 182 } 183 184 /* 185 * Authorisation record for request_key(). 186 */ 187 struct request_key_auth { 188 struct key *target_key; 189 struct key *dest_keyring; 190 const struct cred *cred; 191 void *callout_info; 192 size_t callout_len; 193 pid_t pid; 194 }; 195 196 extern struct key_type key_type_request_key_auth; 197 extern struct key *request_key_auth_new(struct key *target, 198 const void *callout_info, 199 size_t callout_len, 200 struct key *dest_keyring); 201 202 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 203 204 /* 205 * Determine whether a key is dead. 206 */ 207 static inline bool key_is_dead(const struct key *key, time_t limit) 208 { 209 return 210 key->flags & ((1 << KEY_FLAG_DEAD) | 211 (1 << KEY_FLAG_INVALIDATED)) || 212 (key->expiry > 0 && key->expiry <= limit); 213 } 214 215 /* 216 * keyctl() functions 217 */ 218 extern long keyctl_get_keyring_ID(key_serial_t, int); 219 extern long keyctl_join_session_keyring(const char __user *); 220 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 221 extern long keyctl_revoke_key(key_serial_t); 222 extern long keyctl_keyring_clear(key_serial_t); 223 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 224 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 225 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 226 extern long keyctl_keyring_search(key_serial_t, const char __user *, 227 const char __user *, key_serial_t); 228 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 229 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 230 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 231 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 232 size_t, key_serial_t); 233 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 234 extern long keyctl_set_reqkey_keyring(int); 235 extern long keyctl_set_timeout(key_serial_t, unsigned); 236 extern long keyctl_assume_authority(key_serial_t); 237 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 238 size_t buflen); 239 extern long keyctl_session_to_parent(void); 240 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 241 extern long keyctl_instantiate_key_iov(key_serial_t, 242 const struct iovec __user *, 243 unsigned, key_serial_t); 244 extern long keyctl_invalidate_key(key_serial_t); 245 246 extern long keyctl_instantiate_key_common(key_serial_t, 247 const struct iovec *, 248 unsigned, size_t, key_serial_t); 249 #ifdef CONFIG_PERSISTENT_KEYRINGS 250 extern long keyctl_get_persistent(uid_t, key_serial_t); 251 extern unsigned persistent_keyring_expiry; 252 #else 253 static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring) 254 { 255 return -EOPNOTSUPP; 256 } 257 #endif 258 259 /* 260 * Debugging key validation 261 */ 262 #ifdef KEY_DEBUGGING 263 extern void __key_check(const struct key *); 264 265 static inline void key_check(const struct key *key) 266 { 267 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 268 __key_check(key); 269 } 270 271 #else 272 273 #define key_check(key) do {} while(0) 274 275 #endif 276 277 #endif /* _INTERNAL_H */ 278