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 18 static inline __attribute__((format(printf, 1, 2))) 19 void 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 39 extern 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 */ 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 rb_root key_serial_tree; 82 extern spinlock_t key_serial_lock; 83 extern struct mutex key_construction_mutex; 84 extern wait_queue_head_t request_key_conswq; 85 86 87 extern struct key_type *key_type_lookup(const char *type); 88 extern void key_type_put(struct key_type *ktype); 89 90 extern int __key_link(struct key *keyring, struct key *key); 91 92 extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, 93 const struct key_type *type, 94 const char *description, 95 key_perm_t perm); 96 97 extern struct key *keyring_search_instkey(struct key *keyring, 98 key_serial_t target_id); 99 100 typedef int (*key_match_func_t)(const struct key *, const void *); 101 102 extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, 103 const struct cred *cred, 104 struct key_type *type, 105 const void *description, 106 key_match_func_t match); 107 108 extern key_ref_t search_process_keyrings(struct key_type *type, 109 const void *description, 110 key_match_func_t match, 111 const struct cred *cred); 112 113 extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); 114 115 extern int install_user_keyrings(void); 116 extern int install_thread_keyring_to_cred(struct cred *); 117 extern int install_process_keyring_to_cred(struct cred *); 118 119 extern struct key *request_key_and_link(struct key_type *type, 120 const char *description, 121 const void *callout_info, 122 size_t callout_len, 123 void *aux, 124 struct key *dest_keyring, 125 unsigned long flags); 126 127 extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, 128 key_perm_t perm); 129 #define KEY_LOOKUP_CREATE 0x01 130 #define KEY_LOOKUP_PARTIAL 0x02 131 #define KEY_LOOKUP_FOR_UNLINK 0x04 132 133 extern long join_session_keyring(const char *name); 134 135 extern unsigned key_gc_delay; 136 extern void keyring_gc(struct key *keyring, time_t limit); 137 extern void key_schedule_gc(time_t expiry_at); 138 139 /* 140 * check to see whether permission is granted to use a key in the desired way 141 */ 142 extern int key_task_permission(const key_ref_t key_ref, 143 const struct cred *cred, 144 key_perm_t perm); 145 146 static inline int key_permission(const key_ref_t key_ref, key_perm_t perm) 147 { 148 return key_task_permission(key_ref, current_cred(), perm); 149 } 150 151 /* required permissions */ 152 #define KEY_VIEW 0x01 /* require permission to view attributes */ 153 #define KEY_READ 0x02 /* require permission to read content */ 154 #define KEY_WRITE 0x04 /* require permission to update / modify */ 155 #define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */ 156 #define KEY_LINK 0x10 /* require permission to link */ 157 #define KEY_SETATTR 0x20 /* require permission to change attributes */ 158 #define KEY_ALL 0x3f /* all the above permissions */ 159 160 /* 161 * request_key authorisation 162 */ 163 struct request_key_auth { 164 struct key *target_key; 165 struct key *dest_keyring; 166 const struct cred *cred; 167 void *callout_info; 168 size_t callout_len; 169 pid_t pid; 170 }; 171 172 extern struct key_type key_type_request_key_auth; 173 extern struct key *request_key_auth_new(struct key *target, 174 const void *callout_info, 175 size_t callout_len, 176 struct key *dest_keyring); 177 178 extern struct key *key_get_instantiation_authkey(key_serial_t target_id); 179 180 /* 181 * keyctl functions 182 */ 183 extern long keyctl_get_keyring_ID(key_serial_t, int); 184 extern long keyctl_join_session_keyring(const char __user *); 185 extern long keyctl_update_key(key_serial_t, const void __user *, size_t); 186 extern long keyctl_revoke_key(key_serial_t); 187 extern long keyctl_keyring_clear(key_serial_t); 188 extern long keyctl_keyring_link(key_serial_t, key_serial_t); 189 extern long keyctl_keyring_unlink(key_serial_t, key_serial_t); 190 extern long keyctl_describe_key(key_serial_t, char __user *, size_t); 191 extern long keyctl_keyring_search(key_serial_t, const char __user *, 192 const char __user *, key_serial_t); 193 extern long keyctl_read_key(key_serial_t, char __user *, size_t); 194 extern long keyctl_chown_key(key_serial_t, uid_t, gid_t); 195 extern long keyctl_setperm_key(key_serial_t, key_perm_t); 196 extern long keyctl_instantiate_key(key_serial_t, const void __user *, 197 size_t, key_serial_t); 198 extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t); 199 extern long keyctl_set_reqkey_keyring(int); 200 extern long keyctl_set_timeout(key_serial_t, unsigned); 201 extern long keyctl_assume_authority(key_serial_t); 202 extern long keyctl_get_security(key_serial_t keyid, char __user *buffer, 203 size_t buflen); 204 extern long keyctl_session_to_parent(void); 205 206 /* 207 * debugging key validation 208 */ 209 #ifdef KEY_DEBUGGING 210 extern void __key_check(const struct key *); 211 212 static inline void key_check(const struct key *key) 213 { 214 if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC)) 215 __key_check(key); 216 } 217 218 #else 219 220 #define key_check(key) do {} while(0) 221 222 #endif 223 224 #endif /* _INTERNAL_H */ 225