internal.h revision b2a4df200d570b2c33a57e1ebfa5896e4bc81b69
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 19struct 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 37extern struct key_type key_type_dead; 38extern struct key_type key_type_user; 39extern 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 */ 50struct 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 62extern struct rb_root key_user_tree; 63extern spinlock_t key_user_lock; 64extern struct key_user root_key_user; 65 66extern struct key_user *key_user_lookup(kuid_t uid); 67extern 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 */ 73extern unsigned key_quota_root_maxkeys; 74extern unsigned key_quota_root_maxbytes; 75extern unsigned key_quota_maxkeys; 76extern unsigned key_quota_maxbytes; 77 78#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */ 79 80 81extern struct kmem_cache *key_jar; 82extern struct rb_root key_serial_tree; 83extern spinlock_t key_serial_lock; 84extern struct mutex key_construction_mutex; 85extern wait_queue_head_t request_key_conswq; 86 87 88extern struct key_type *key_type_lookup(const char *type); 89extern void key_type_put(struct key_type *ktype); 90 91extern int __key_link_begin(struct key *keyring, 92 const struct keyring_index_key *index_key, 93 struct assoc_array_edit **_edit); 94extern int __key_link_check_live_key(struct key *keyring, struct key *key); 95extern void __key_link(struct key *key, struct assoc_array_edit **_edit); 96extern void __key_link_end(struct key *keyring, 97 const struct keyring_index_key *index_key, 98 struct assoc_array_edit *edit); 99 100extern key_ref_t find_key_to_update(key_ref_t keyring_ref, 101 const struct keyring_index_key *index_key); 102 103extern struct key *keyring_search_instkey(struct key *keyring, 104 key_serial_t target_id); 105 106extern int iterate_over_keyring(const struct key *keyring, 107 int (*func)(const struct key *key, void *data), 108 void *data); 109 110typedef int (*key_match_func_t)(const struct key *, const void *); 111 112struct 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 134extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 135 struct keyring_search_context *ctx); 136 137extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); 138extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); 139 140extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 141 142extern int install_user_keyrings(void); 143extern int install_thread_keyring_to_cred(struct cred *); 144extern int install_process_keyring_to_cred(struct cred *); 145extern int install_session_keyring_to_cred(struct cred *, struct key *); 146 147extern 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 155extern int lookup_user_key_possessed(const struct key *key, const void *target); 156extern 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 162extern long join_session_keyring(const char *name); 163extern void key_change_session_keyring(struct callback_head *twork); 164 165extern struct work_struct key_gc_work; 166extern unsigned key_gc_delay; 167extern void keyring_gc(struct key *keyring, time_t limit); 168extern void key_schedule_gc(time_t gc_at); 169extern void key_schedule_gc_links(void); 170extern void key_gc_keytype(struct key_type *ktype); 171 172extern 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 */ 179static 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 */ 196struct 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 205extern struct key_type key_type_request_key_auth; 206extern 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 211extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 212 213/* 214 * Determine whether a key is dead. 215 */ 216static 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 */ 227extern long keyctl_get_keyring_ID(key_serial_t, int); 228extern long keyctl_join_session_keyring(const char __user *); 229extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 230extern long keyctl_revoke_key(key_serial_t); 231extern long keyctl_keyring_clear(key_serial_t); 232extern long keyctl_keyring_link(key_serial_t, key_serial_t); 233extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 234extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 235extern long keyctl_keyring_search(key_serial_t, const char __user *, 236 const char __user *, key_serial_t); 237extern long keyctl_read_key(key_serial_t, char __user *, size_t); 238extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 239extern long keyctl_setperm_key(key_serial_t, key_perm_t); 240extern long keyctl_instantiate_key(key_serial_t, const void __user *, 241 size_t, key_serial_t); 242extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 243extern long keyctl_set_reqkey_keyring(int); 244extern long keyctl_set_timeout(key_serial_t, unsigned); 245extern long keyctl_assume_authority(key_serial_t); 246extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 247 size_t buflen); 248extern long keyctl_session_to_parent(void); 249extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t); 250extern long keyctl_instantiate_key_iov(key_serial_t, 251 const struct iovec __user *, 252 unsigned, key_serial_t); 253extern long keyctl_invalidate_key(key_serial_t); 254 255extern long keyctl_instantiate_key_common(key_serial_t, 256 const struct iovec *, 257 unsigned, size_t, key_serial_t); 258 259/* 260 * Debugging key validation 261 */ 262#ifdef KEY_DEBUGGING 263extern void __key_check(const struct key *); 264 265static 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