internal.h revision f70e2e06196ad4c1c762037da2f75354f6c16b81
1/* internal.h: 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 18static inline __attribute__((format(printf, 1, 2))) 19void no_printk(const char *fmt, ...) 20{ 21} 22 23#ifdef __KDEBUG 24#define kenter(FMT, ...) \ 25 printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 26#define kleave(FMT, ...) \ 27 printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 28#define kdebug(FMT, ...) \ 29 printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__) 30#else 31#define kenter(FMT, ...) \ 32 no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__) 33#define kleave(FMT, ...) \ 34 no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__) 35#define kdebug(FMT, ...) \ 36 no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__) 37#endif 38 39extern struct key_type key_type_user; 40 41/*****************************************************************************/ 42/* 43 * keep track of keys for a user 44 * - this needs to be separate to user_struct to avoid a refcount-loop 45 * (user_struct pins some keyrings which pin this struct) 46 * - this also keeps track of keys under request from userspace for this UID 47 */ 48struct 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 61extern struct rb_root key_user_tree; 62extern spinlock_t key_user_lock; 63extern struct key_user root_key_user; 64 65extern struct key_user *key_user_lookup(uid_t uid, 66 struct user_namespace *user_ns); 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 rb_root key_serial_tree; 82extern spinlock_t key_serial_lock; 83extern struct mutex key_construction_mutex; 84extern wait_queue_head_t request_key_conswq; 85 86 87extern struct key_type *key_type_lookup(const char *type); 88extern void key_type_put(struct key_type *ktype); 89 90extern int __key_link_begin(struct key *keyring, 91 const struct key_type *type, 92 const char *description, 93 struct keyring_list **_prealloc); 94extern int __key_link_check_live_key(struct key *keyring, struct key *key); 95extern void __key_link(struct key *keyring, struct key *key, 96 struct keyring_list **_prealloc); 97extern void __key_link_end(struct key *keyring, 98 struct key_type *type, 99 struct keyring_list *prealloc); 100 101extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, 102 const struct key_type *type, 103 const char *description, 104 key_perm_t perm); 105 106extern struct key *keyring_search_instkey(struct key *keyring, 107 key_serial_t target_id); 108 109typedef int (*key_match_func_t)(const struct key *, const void *); 110 111extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 112 const struct cred *cred, 113 struct key_type *type, 114 const void *description, 115 key_match_func_t match); 116 117extern key_ref_t search_process_keyrings(struct key_type *type, 118 const void *description, 119 key_match_func_t match, 120 const struct cred *cred); 121 122extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 123 124extern int install_user_keyrings(void); 125extern int install_thread_keyring_to_cred(struct cred *); 126extern int install_process_keyring_to_cred(struct cred *); 127 128extern struct key *request_key_and_link(struct key_type *type, 129 const char *description, 130 const void *callout_info, 131 size_t callout_len, 132 void *aux, 133 struct key *dest_keyring, 134 unsigned long flags); 135 136extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 137 key_perm_t perm); 138#define KEY_LOOKUP_CREATE 0x01 139#define KEY_LOOKUP_PARTIAL 0x02 140#define KEY_LOOKUP_FOR_UNLINK 0x04 141 142extern long join_session_keyring(const char *name); 143 144extern unsigned key_gc_delay; 145extern void keyring_gc(struct key *keyring, time_t limit); 146extern void key_schedule_gc(time_t expiry_at); 147 148/* 149 * check to see whether permission is granted to use a key in the desired way 150 */ 151extern int key_task_permission(const key_ref_t key_ref, 152 const struct cred *cred, 153 key_perm_t perm); 154 155static inline int key_permission(const key_ref_t key_ref, key_perm_t perm) 156{ 157 return key_task_permission(key_ref, current_cred(), perm); 158} 159 160/* required permissions */ 161#define KEY_VIEW 0x01 /* require permission to view attributes */ 162#define KEY_READ 0x02 /* require permission to read content */ 163#define KEY_WRITE 0x04 /* require permission to update / modify */ 164#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */ 165#define KEY_LINK 0x10 /* require permission to link */ 166#define KEY_SETATTR 0x20 /* require permission to change attributes */ 167#define KEY_ALL 0x3f /* all the above permissions */ 168 169/* 170 * request_key authorisation 171 */ 172struct request_key_auth { 173 struct key *target_key; 174 struct key *dest_keyring; 175 const struct cred *cred; 176 void *callout_info; 177 size_t callout_len; 178 pid_t pid; 179}; 180 181extern struct key_type key_type_request_key_auth; 182extern struct key *request_key_auth_new(struct key *target, 183 const void *callout_info, 184 size_t callout_len, 185 struct key *dest_keyring); 186 187extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 188 189/* 190 * keyctl functions 191 */ 192extern long keyctl_get_keyring_ID(key_serial_t, int); 193extern long keyctl_join_session_keyring(const char __user *); 194extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 195extern long keyctl_revoke_key(key_serial_t); 196extern long keyctl_keyring_clear(key_serial_t); 197extern long keyctl_keyring_link(key_serial_t, key_serial_t); 198extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 199extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 200extern long keyctl_keyring_search(key_serial_t, const char __user *, 201 const char __user *, key_serial_t); 202extern long keyctl_read_key(key_serial_t, char __user *, size_t); 203extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 204extern long keyctl_setperm_key(key_serial_t, key_perm_t); 205extern long keyctl_instantiate_key(key_serial_t, const void __user *, 206 size_t, key_serial_t); 207extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 208extern long keyctl_set_reqkey_keyring(int); 209extern long keyctl_set_timeout(key_serial_t, unsigned); 210extern long keyctl_assume_authority(key_serial_t); 211extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 212 size_t buflen); 213extern long keyctl_session_to_parent(void); 214 215/* 216 * debugging key validation 217 */ 218#ifdef KEY_DEBUGGING 219extern void __key_check(const struct key *); 220 221static inline void key_check(const struct key *key) 222{ 223 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 224 __key_check(key); 225} 226 227#else 228 229#define key_check(key) do {} while(0) 230 231#endif 232 233#endif /* _INTERNAL_H */ 234