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 uid_t uid; 56 struct user_namespace *user_ns; 57 int qnkeys; /* number of keys allocated to this user */ 58 int qnbytes; /* number of bytes allocated to this user */ 59 }; 60 61 extern struct rb_root key_user_tree; 62 extern spinlock_t key_user_lock; 63 extern struct key_user root_key_user; 64 65 extern struct key_user *key_user_lookup(uid_t uid, 66 struct user_namespace *user_ns); 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 key_type *type, 93 const char *description, 94 unsigned long *_prealloc); 95 extern int __key_link_check_live_key(struct key *keyring, struct key *key); 96 extern void __key_link(struct key *keyring, struct key *key, 97 unsigned long *_prealloc); 98 extern void __key_link_end(struct key *keyring, 99 struct key_type *type, 100 unsigned long prealloc); 101 102 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, 103 const struct key_type *type, 104 const char *description, 105 key_perm_t perm); 106 107 extern struct key *keyring_search_instkey(struct key *keyring, 108 key_serial_t target_id); 109 110 typedef int (*key_match_func_t)(const struct key *, const void *); 111 112 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 113 const struct cred *cred, 114 struct key_type *type, 115 const void *description, 116 key_match_func_t match, 117 bool no_state_check); 118 119 extern key_ref_t search_my_process_keyrings(struct key_type *type, 120 const void *description, 121 key_match_func_t match, 122 bool no_state_check, 123 const struct cred *cred); 124 extern key_ref_t search_process_keyrings(struct key_type *type, 125 const void *description, 126 key_match_func_t match, 127 const struct cred *cred); 128 129 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 130 131 extern int install_user_keyrings(void); 132 extern int install_thread_keyring_to_cred(struct cred *); 133 extern int install_process_keyring_to_cred(struct cred *); 134 extern int install_session_keyring_to_cred(struct cred *, struct key *); 135 136 extern struct key *request_key_and_link(struct key_type *type, 137 const char *description, 138 const void *callout_info, 139 size_t callout_len, 140 void *aux, 141 struct key *dest_keyring, 142 unsigned long flags); 143 144 extern int lookup_user_key_possessed(const struct key *key, const void *target); 145 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 146 key_perm_t perm); 147 #define KEY_LOOKUP_CREATE 0x01 148 #define KEY_LOOKUP_PARTIAL 0x02 149 #define KEY_LOOKUP_FOR_UNLINK 0x04 150 151 struct kludge { /* this will die off very soon */ 152 struct task_work twork; 153 struct cred *cred; 154 }; 155 extern long join_session_keyring(const char *name); 156 extern void key_change_session_keyring(struct task_work *twork); 157 158 extern struct work_struct key_gc_work; 159 extern unsigned key_gc_delay; 160 extern void keyring_gc(struct key *keyring, time_t limit); 161 extern void key_schedule_gc(time_t gc_at); 162 extern void key_schedule_gc_links(void); 163 extern void key_gc_keytype(struct key_type *ktype); 164 165 extern int key_task_permission(const key_ref_t key_ref, 166 const struct cred *cred, 167 key_perm_t perm); 168 169 /* 170 * Check to see whether permission is granted to use a key in the desired way. 171 */ 172 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm) 173 { 174 return key_task_permission(key_ref, current_cred(), perm); 175 } 176 177 /* required permissions */ 178 #define KEY_VIEW 0x01 /* require permission to view attributes */ 179 #define KEY_READ 0x02 /* require permission to read content */ 180 #define KEY_WRITE 0x04 /* require permission to update / modify */ 181 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */ 182 #define KEY_LINK 0x10 /* require permission to link */ 183 #define KEY_SETATTR 0x20 /* require permission to change attributes */ 184 #define KEY_ALL 0x3f /* all the above permissions */ 185 186 /* 187 * Authorisation record for request_key(). 188 */ 189 struct request_key_auth { 190 struct key *target_key; 191 struct key *dest_keyring; 192 const struct cred *cred; 193 void *callout_info; 194 size_t callout_len; 195 pid_t pid; 196 }; 197 198 extern struct key_type key_type_request_key_auth; 199 extern struct key *request_key_auth_new(struct key *target, 200 const void *callout_info, 201 size_t callout_len, 202 struct key *dest_keyring); 203 204 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 205 206 /* 207 * Determine whether a key is dead. 208 */ 209 static inline bool key_is_dead(struct key *key, time_t limit) 210 { 211 return 212 key->flags & ((1 << KEY_FLAG_DEAD) | 213 (1 << KEY_FLAG_INVALIDATED)) || 214 (key->expiry > 0 && key->expiry <= limit); 215 } 216 217 /* 218 * keyctl() functions 219 */ 220 extern long keyctl_get_keyring_ID(key_serial_t, int); 221 extern long keyctl_join_session_keyring(const char __user *); 222 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 223 extern long keyctl_revoke_key(key_serial_t); 224 extern long keyctl_keyring_clear(key_serial_t); 225 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 226 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 227 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 228 extern long keyctl_keyring_search(key_serial_t, const char __user *, 229 const char __user *, key_serial_t); 230 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 231 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 232 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 233 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 234 size_t, key_serial_t); 235 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 236 extern long keyctl_set_reqkey_keyring(int); 237 extern long keyctl_set_timeout(key_serial_t, unsigned); 238 extern long keyctl_assume_authority(key_serial_t); 239 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 240 size_t buflen); 241 extern long keyctl_session_to_parent(void); 242 extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 243 extern long keyctl_instantiate_key_iov(key_serial_t, 244 const struct iovec __user *, 245 unsigned, key_serial_t); 246 extern long keyctl_invalidate_key(key_serial_t); 247 248 extern long keyctl_instantiate_key_common(key_serial_t, 249 const struct iovec __user *, 250 unsigned, size_t, key_serial_t); 251 252 /* 253 * Debugging key validation 254 */ 255 #ifdef KEY_DEBUGGING 256 extern void __key_check(const struct key *); 257 258 static inline void key_check(const struct key *key) 259 { 260 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 261 __key_check(key); 262 } 263 264 #else 265 266 #define key_check(key) do {} while(0) 267 268 #endif 269 270 #endif /* _INTERNAL_H */ 271