David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 1 | /* Basic authentication token and access key management |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | #include <linux/module.h> |
| 13 | #include <linux/init.h> |
Randy Dunlap | a7807a3 | 2006-06-27 02:53:54 -0700 | [diff] [blame] | 14 | #include <linux/poison.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/sched.h> |
| 16 | #include <linux/slab.h> |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 17 | #include <linux/security.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/workqueue.h> |
Michael LeMay | e51f6d3 | 2006-06-26 00:24:54 -0700 | [diff] [blame] | 19 | #include <linux/random.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/err.h> |
| 21 | #include "internal.h" |
| 22 | |
David Howells | 8bc16de | 2011-08-22 14:09:11 +0100 | [diff] [blame] | 23 | struct kmem_cache *key_jar; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | struct rb_root key_serial_tree; /* tree of keys indexed by serial */ |
| 25 | DEFINE_SPINLOCK(key_serial_lock); |
| 26 | |
| 27 | struct rb_root key_user_tree; /* tree of quota records indexed by UID */ |
| 28 | DEFINE_SPINLOCK(key_user_lock); |
| 29 | |
Steve Dickson | 738c5d1 | 2014-09-02 13:52:05 +0100 | [diff] [blame] | 30 | unsigned int key_quota_root_maxkeys = 1000000; /* root's key count quota */ |
| 31 | unsigned int key_quota_root_maxbytes = 25000000; /* root's key space quota */ |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 32 | unsigned int key_quota_maxkeys = 200; /* general key count quota */ |
| 33 | unsigned int key_quota_maxbytes = 20000; /* general key space quota */ |
| 34 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | static LIST_HEAD(key_types_list); |
| 36 | static DECLARE_RWSEM(key_types_sem); |
| 37 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 38 | /* We serialise key instantiation and link */ |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 39 | DEFINE_MUTEX(key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | #ifdef KEY_DEBUGGING |
| 42 | void __key_check(const struct key *key) |
| 43 | { |
| 44 | printk("__key_check: key %p {%08x} should be {%08x}\n", |
| 45 | key, key->magic, KEY_DEBUG_MAGIC); |
| 46 | BUG(); |
| 47 | } |
| 48 | #endif |
| 49 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 51 | * Get the key quota record for a user, allocating a new record if one doesn't |
| 52 | * already exist. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | */ |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 54 | struct key_user *key_user_lookup(kuid_t uid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | { |
| 56 | struct key_user *candidate = NULL, *user; |
| 57 | struct rb_node *parent = NULL; |
| 58 | struct rb_node **p; |
| 59 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 60 | try_again: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | p = &key_user_tree.rb_node; |
| 62 | spin_lock(&key_user_lock); |
| 63 | |
| 64 | /* search the tree for a user record with a matching UID */ |
| 65 | while (*p) { |
| 66 | parent = *p; |
| 67 | user = rb_entry(parent, struct key_user, node); |
| 68 | |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 69 | if (uid_lt(uid, user->uid)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | p = &(*p)->rb_left; |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 71 | else if (uid_gt(uid, user->uid)) |
Serge E. Hallyn | 1d1e975 | 2009-02-26 18:27:38 -0600 | [diff] [blame] | 72 | p = &(*p)->rb_right; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | else |
| 74 | goto found; |
| 75 | } |
| 76 | |
| 77 | /* if we get here, we failed to find a match in the tree */ |
| 78 | if (!candidate) { |
| 79 | /* allocate a candidate user record if we don't already have |
| 80 | * one */ |
| 81 | spin_unlock(&key_user_lock); |
| 82 | |
| 83 | user = NULL; |
| 84 | candidate = kmalloc(sizeof(struct key_user), GFP_KERNEL); |
| 85 | if (unlikely(!candidate)) |
| 86 | goto out; |
| 87 | |
| 88 | /* the allocation may have scheduled, so we need to repeat the |
| 89 | * search lest someone else added the record whilst we were |
| 90 | * asleep */ |
| 91 | goto try_again; |
| 92 | } |
| 93 | |
| 94 | /* if we get here, then the user record still hadn't appeared on the |
| 95 | * second pass - so we use the candidate record */ |
| 96 | atomic_set(&candidate->usage, 1); |
| 97 | atomic_set(&candidate->nkeys, 0); |
| 98 | atomic_set(&candidate->nikeys, 0); |
| 99 | candidate->uid = uid; |
| 100 | candidate->qnkeys = 0; |
| 101 | candidate->qnbytes = 0; |
| 102 | spin_lock_init(&candidate->lock); |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 103 | mutex_init(&candidate->cons_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | |
| 105 | rb_link_node(&candidate->node, parent, p); |
| 106 | rb_insert_color(&candidate->node, &key_user_tree); |
| 107 | spin_unlock(&key_user_lock); |
| 108 | user = candidate; |
| 109 | goto out; |
| 110 | |
| 111 | /* okay - we found a user record for this UID */ |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 112 | found: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | atomic_inc(&user->usage); |
| 114 | spin_unlock(&key_user_lock); |
Jesper Juhl | a7f988b | 2005-11-07 01:01:35 -0800 | [diff] [blame] | 115 | kfree(candidate); |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 116 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | return user; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 118 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 121 | * Dispose of a user structure |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | */ |
| 123 | void key_user_put(struct key_user *user) |
| 124 | { |
| 125 | if (atomic_dec_and_lock(&user->usage, &key_user_lock)) { |
| 126 | rb_erase(&user->node, &key_user_tree); |
| 127 | spin_unlock(&key_user_lock); |
| 128 | |
| 129 | kfree(user); |
| 130 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 131 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 134 | * Allocate a serial number for a key. These are assigned randomly to avoid |
| 135 | * security issues through covert channel problems. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | */ |
| 137 | static inline void key_alloc_serial(struct key *key) |
| 138 | { |
| 139 | struct rb_node *parent, **p; |
| 140 | struct key *xkey; |
| 141 | |
Michael LeMay | e51f6d3 | 2006-06-26 00:24:54 -0700 | [diff] [blame] | 142 | /* propose a random serial number and look for a hole for it in the |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | * serial number tree */ |
Michael LeMay | e51f6d3 | 2006-06-26 00:24:54 -0700 | [diff] [blame] | 144 | do { |
| 145 | get_random_bytes(&key->serial, sizeof(key->serial)); |
| 146 | |
| 147 | key->serial >>= 1; /* negative numbers are not permitted */ |
| 148 | } while (key->serial < 3); |
| 149 | |
| 150 | spin_lock(&key_serial_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | |
David Howells | 9ad0830 | 2007-02-06 13:45:51 +0000 | [diff] [blame] | 152 | attempt_insertion: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | parent = NULL; |
| 154 | p = &key_serial_tree.rb_node; |
| 155 | |
| 156 | while (*p) { |
| 157 | parent = *p; |
| 158 | xkey = rb_entry(parent, struct key, serial_node); |
| 159 | |
| 160 | if (key->serial < xkey->serial) |
| 161 | p = &(*p)->rb_left; |
| 162 | else if (key->serial > xkey->serial) |
| 163 | p = &(*p)->rb_right; |
| 164 | else |
| 165 | goto serial_exists; |
| 166 | } |
David Howells | 9ad0830 | 2007-02-06 13:45:51 +0000 | [diff] [blame] | 167 | |
| 168 | /* we've found a suitable hole - arrange for this key to occupy it */ |
| 169 | rb_link_node(&key->serial_node, parent, p); |
| 170 | rb_insert_color(&key->serial_node, &key_serial_tree); |
| 171 | |
| 172 | spin_unlock(&key_serial_lock); |
| 173 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | |
| 175 | /* we found a key with the proposed serial number - walk the tree from |
| 176 | * that point looking for the next unused serial number */ |
Michael LeMay | e51f6d3 | 2006-06-26 00:24:54 -0700 | [diff] [blame] | 177 | serial_exists: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | for (;;) { |
Michael LeMay | e51f6d3 | 2006-06-26 00:24:54 -0700 | [diff] [blame] | 179 | key->serial++; |
David Howells | 9ad0830 | 2007-02-06 13:45:51 +0000 | [diff] [blame] | 180 | if (key->serial < 3) { |
| 181 | key->serial = 3; |
| 182 | goto attempt_insertion; |
| 183 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | |
| 185 | parent = rb_next(parent); |
| 186 | if (!parent) |
David Howells | 9ad0830 | 2007-02-06 13:45:51 +0000 | [diff] [blame] | 187 | goto attempt_insertion; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | |
| 189 | xkey = rb_entry(parent, struct key, serial_node); |
| 190 | if (key->serial < xkey->serial) |
David Howells | 9ad0830 | 2007-02-06 13:45:51 +0000 | [diff] [blame] | 191 | goto attempt_insertion; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 193 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 195 | /** |
| 196 | * key_alloc - Allocate a key of the specified type. |
| 197 | * @type: The type of key to allocate. |
| 198 | * @desc: The key description to allow the key to be searched out. |
| 199 | * @uid: The owner of the new key. |
| 200 | * @gid: The group ID for the new key's group permissions. |
| 201 | * @cred: The credentials specifying UID namespace. |
| 202 | * @perm: The permissions mask of the new key. |
| 203 | * @flags: Flags specifying quota properties. |
| 204 | * |
| 205 | * Allocate a key of the specified type with the attributes given. The key is |
| 206 | * returned in an uninstantiated state and the caller needs to instantiate the |
| 207 | * key before returning. |
| 208 | * |
| 209 | * The user's key count quota is updated to reflect the creation of the key and |
| 210 | * the user's key data quota has the default for the key type reserved. The |
| 211 | * instantiation function should amend this as necessary. If insufficient |
| 212 | * quota is available, -EDQUOT will be returned. |
| 213 | * |
| 214 | * The LSM security modules can prevent a key being created, in which case |
| 215 | * -EACCES will be returned. |
| 216 | * |
| 217 | * Returns a pointer to the new key if successful and an error code otherwise. |
| 218 | * |
| 219 | * Note that the caller needs to ensure the key type isn't uninstantiated. |
| 220 | * Internally this can be done by locking key_types_sem. Externally, this can |
| 221 | * be done by either never unregistering the key type, or making sure |
| 222 | * key_alloc() calls don't race with module unloading. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | */ |
| 224 | struct key *key_alloc(struct key_type *type, const char *desc, |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 225 | kuid_t uid, kgid_t gid, const struct cred *cred, |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 226 | key_perm_t perm, unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | { |
| 228 | struct key_user *user = NULL; |
| 229 | struct key *key; |
| 230 | size_t desclen, quotalen; |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 231 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | |
| 233 | key = ERR_PTR(-EINVAL); |
| 234 | if (!desc || !*desc) |
| 235 | goto error; |
| 236 | |
David Howells | b9fffa3 | 2011-03-07 15:05:59 +0000 | [diff] [blame] | 237 | if (type->vet_description) { |
| 238 | ret = type->vet_description(desc); |
| 239 | if (ret < 0) { |
| 240 | key = ERR_PTR(ret); |
| 241 | goto error; |
| 242 | } |
| 243 | } |
| 244 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 245 | desclen = strlen(desc); |
| 246 | quotalen = desclen + 1 + type->def_datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | |
| 248 | /* get hold of the key tracking for this user */ |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 249 | user = key_user_lookup(uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | if (!user) |
| 251 | goto no_memory_1; |
| 252 | |
| 253 | /* check that the user's quota permits allocation of another key and |
| 254 | * its description */ |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 255 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 256 | unsigned maxkeys = uid_eq(uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 257 | key_quota_root_maxkeys : key_quota_maxkeys; |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 258 | unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 259 | key_quota_root_maxbytes : key_quota_maxbytes; |
| 260 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | spin_lock(&user->lock); |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 262 | if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 263 | if (user->qnkeys + 1 >= maxkeys || |
| 264 | user->qnbytes + quotalen >= maxbytes || |
| 265 | user->qnbytes + quotalen < user->qnbytes) |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 266 | goto no_quota; |
| 267 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | |
| 269 | user->qnkeys++; |
| 270 | user->qnbytes += quotalen; |
| 271 | spin_unlock(&user->lock); |
| 272 | } |
| 273 | |
| 274 | /* allocate and initialise the key and its description */ |
David Howells | 2480f57 | 2013-12-02 11:24:18 +0000 | [diff] [blame] | 275 | key = kmem_cache_zalloc(key_jar, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | if (!key) |
| 277 | goto no_memory_2; |
| 278 | |
Dan Carpenter | 5057975 | 2014-12-11 19:59:38 +0000 | [diff] [blame] | 279 | key->index_key.desc_len = desclen; |
| 280 | key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL); |
| 281 | if (!key->description) |
| 282 | goto no_memory_3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | |
| 284 | atomic_set(&key->usage, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | init_rwsem(&key->sem); |
David Howells | 7845bc39 | 2011-11-16 11:15:54 +0000 | [diff] [blame] | 286 | lockdep_set_class(&key->sem, &type->lock_class); |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 287 | key->index_key.type = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | key->user = user; |
| 289 | key->quotalen = quotalen; |
| 290 | key->datalen = type->def_datalen; |
| 291 | key->uid = uid; |
| 292 | key->gid = gid; |
| 293 | key->perm = perm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 295 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 296 | key->flags |= 1 << KEY_FLAG_IN_QUOTA; |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 297 | if (flags & KEY_ALLOC_TRUSTED) |
| 298 | key->flags |= 1 << KEY_FLAG_TRUSTED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | #ifdef KEY_DEBUGGING |
| 301 | key->magic = KEY_DEBUG_MAGIC; |
| 302 | #endif |
| 303 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 304 | /* let the security module know about the key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 305 | ret = security_key_alloc(key, cred, flags); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 306 | if (ret < 0) |
| 307 | goto security_error; |
| 308 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | /* publish the key by giving it a serial number */ |
| 310 | atomic_inc(&user->nkeys); |
| 311 | key_alloc_serial(key); |
| 312 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 313 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | return key; |
| 315 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 316 | security_error: |
| 317 | kfree(key->description); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | kmem_cache_free(key_jar, key); |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 319 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | spin_lock(&user->lock); |
| 321 | user->qnkeys--; |
| 322 | user->qnbytes -= quotalen; |
| 323 | spin_unlock(&user->lock); |
| 324 | } |
| 325 | key_user_put(user); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 326 | key = ERR_PTR(ret); |
| 327 | goto error; |
| 328 | |
| 329 | no_memory_3: |
| 330 | kmem_cache_free(key_jar, key); |
| 331 | no_memory_2: |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 332 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 333 | spin_lock(&user->lock); |
| 334 | user->qnkeys--; |
| 335 | user->qnbytes -= quotalen; |
| 336 | spin_unlock(&user->lock); |
| 337 | } |
| 338 | key_user_put(user); |
| 339 | no_memory_1: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | key = ERR_PTR(-ENOMEM); |
| 341 | goto error; |
| 342 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 343 | no_quota: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | spin_unlock(&user->lock); |
| 345 | key_user_put(user); |
| 346 | key = ERR_PTR(-EDQUOT); |
| 347 | goto error; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 348 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | EXPORT_SYMBOL(key_alloc); |
| 350 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 351 | /** |
| 352 | * key_payload_reserve - Adjust data quota reservation for the key's payload |
| 353 | * @key: The key to make the reservation for. |
| 354 | * @datalen: The amount of data payload the caller now wants. |
| 355 | * |
| 356 | * Adjust the amount of the owning user's key data quota that a key reserves. |
| 357 | * If the amount is increased, then -EDQUOT may be returned if there isn't |
| 358 | * enough free quota available. |
| 359 | * |
| 360 | * If successful, 0 is returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | */ |
| 362 | int key_payload_reserve(struct key *key, size_t datalen) |
| 363 | { |
Justin P. Mattock | c5b60b5 | 2010-04-21 00:02:11 -0700 | [diff] [blame] | 364 | int delta = (int)datalen - key->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | int ret = 0; |
| 366 | |
| 367 | key_check(key); |
| 368 | |
| 369 | /* contemplate the quota adjustment */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 370 | if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) { |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 371 | unsigned maxbytes = uid_eq(key->user->uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 372 | key_quota_root_maxbytes : key_quota_maxbytes; |
| 373 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | spin_lock(&key->user->lock); |
| 375 | |
| 376 | if (delta > 0 && |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 377 | (key->user->qnbytes + delta >= maxbytes || |
| 378 | key->user->qnbytes + delta < key->user->qnbytes)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | ret = -EDQUOT; |
| 380 | } |
| 381 | else { |
| 382 | key->user->qnbytes += delta; |
| 383 | key->quotalen += delta; |
| 384 | } |
| 385 | spin_unlock(&key->user->lock); |
| 386 | } |
| 387 | |
| 388 | /* change the recorded data length if that didn't generate an error */ |
| 389 | if (ret == 0) |
| 390 | key->datalen = datalen; |
| 391 | |
| 392 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 393 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | EXPORT_SYMBOL(key_payload_reserve); |
| 395 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 397 | * Instantiate a key and link it into the target keyring atomically. Must be |
| 398 | * called with the target keyring's semaphore writelocked. The target key's |
| 399 | * semaphore need not be locked as instantiation is serialised by |
| 400 | * key_construction_mutex. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | */ |
| 402 | static int __key_instantiate_and_link(struct key *key, |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 403 | struct key_preparsed_payload *prep, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 404 | struct key *keyring, |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 405 | struct key *authkey, |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 406 | struct assoc_array_edit **_edit) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | { |
| 408 | int ret, awaken; |
| 409 | |
| 410 | key_check(key); |
| 411 | key_check(keyring); |
| 412 | |
| 413 | awaken = 0; |
| 414 | ret = -EBUSY; |
| 415 | |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 416 | mutex_lock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | |
| 418 | /* can't instantiate twice */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 419 | if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | /* instantiate the key */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 421 | ret = key->type->instantiate(key, prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | |
| 423 | if (ret == 0) { |
| 424 | /* mark the key as being instantiated */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | atomic_inc(&key->user->nikeys); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 426 | set_bit(KEY_FLAG_INSTANTIATED, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 428 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | awaken = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | |
| 431 | /* and link it into the destination keyring */ |
| 432 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 433 | __key_link(key, _edit); |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 434 | |
| 435 | /* disable the authorisation key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 436 | if (authkey) |
| 437 | key_revoke(authkey); |
David Howells | 7dfa0ca6 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 438 | |
| 439 | if (prep->expiry != TIME_T_MAX) { |
| 440 | key->expiry = prep->expiry; |
| 441 | key_schedule_gc(prep->expiry + key_gc_delay); |
| 442 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | } |
| 444 | } |
| 445 | |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 446 | mutex_unlock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | |
| 448 | /* wake up anyone waiting for a key to be constructed */ |
| 449 | if (awaken) |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 450 | wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | |
| 452 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 453 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 455 | /** |
| 456 | * key_instantiate_and_link - Instantiate a key and link it into the keyring. |
| 457 | * @key: The key to instantiate. |
| 458 | * @data: The data to use to instantiate the keyring. |
| 459 | * @datalen: The length of @data. |
| 460 | * @keyring: Keyring to create a link in on success (or NULL). |
| 461 | * @authkey: The authorisation token permitting instantiation. |
| 462 | * |
| 463 | * Instantiate a key that's in the uninstantiated state using the provided data |
| 464 | * and, if successful, link it in to the destination keyring if one is |
| 465 | * supplied. |
| 466 | * |
| 467 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
| 468 | * waiting for the key is woken up. If the key was already instantiated, |
| 469 | * -EBUSY will be returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | */ |
| 471 | int key_instantiate_and_link(struct key *key, |
| 472 | const void *data, |
| 473 | size_t datalen, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 474 | struct key *keyring, |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 475 | struct key *authkey) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | { |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 477 | struct key_preparsed_payload prep; |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 478 | struct assoc_array_edit *edit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | int ret; |
| 480 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 481 | memset(&prep, 0, sizeof(prep)); |
| 482 | prep.data = data; |
| 483 | prep.datalen = datalen; |
| 484 | prep.quotalen = key->type->def_datalen; |
David Howells | 7dfa0ca6 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 485 | prep.expiry = TIME_T_MAX; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 486 | if (key->type->preparse) { |
| 487 | ret = key->type->preparse(&prep); |
| 488 | if (ret < 0) |
| 489 | goto error; |
| 490 | } |
| 491 | |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 492 | if (keyring) { |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 493 | ret = __key_link_begin(keyring, &key->index_key, &edit); |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 494 | if (ret < 0) |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 495 | goto error; |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 496 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 498 | ret = __key_instantiate_and_link(key, &prep, keyring, authkey, &edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | |
| 500 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 501 | __key_link_end(keyring, &key->index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 503 | error: |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 504 | if (key->type->preparse) |
| 505 | key->type->free_preparse(&prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 507 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | |
| 509 | EXPORT_SYMBOL(key_instantiate_and_link); |
| 510 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 511 | /** |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 512 | * key_reject_and_link - Negatively instantiate a key and link it into the keyring. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 513 | * @key: The key to instantiate. |
| 514 | * @timeout: The timeout on the negative key. |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 515 | * @error: The error to return when the key is hit. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 516 | * @keyring: Keyring to create a link in on success (or NULL). |
| 517 | * @authkey: The authorisation token permitting instantiation. |
| 518 | * |
| 519 | * Negatively instantiate a key that's in the uninstantiated state and, if |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 520 | * successful, set its timeout and stored error and link it in to the |
| 521 | * destination keyring if one is supplied. The key and any links to the key |
| 522 | * will be automatically garbage collected after the timeout expires. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 523 | * |
| 524 | * Negative keys are used to rate limit repeated request_key() calls by causing |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 525 | * them to return the stored error code (typically ENOKEY) until the negative |
| 526 | * key expires. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 527 | * |
| 528 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
| 529 | * waiting for the key is woken up. If the key was already instantiated, |
| 530 | * -EBUSY will be returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 531 | */ |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 532 | int key_reject_and_link(struct key *key, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | unsigned timeout, |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 534 | unsigned error, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 535 | struct key *keyring, |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 536 | struct key *authkey) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | { |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 538 | struct assoc_array_edit *edit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | struct timespec now; |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 540 | int ret, awaken, link_ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 541 | |
| 542 | key_check(key); |
| 543 | key_check(keyring); |
| 544 | |
| 545 | awaken = 0; |
| 546 | ret = -EBUSY; |
| 547 | |
| 548 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 549 | link_ret = __key_link_begin(keyring, &key->index_key, &edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 551 | mutex_lock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | |
| 553 | /* can't instantiate twice */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 554 | if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | /* mark the key as being negatively instantiated */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | atomic_inc(&key->user->nikeys); |
David Howells | 74792b0 | 2013-10-30 11:15:24 +0000 | [diff] [blame] | 557 | key->type_data.reject_error = -error; |
| 558 | smp_wmb(); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 559 | set_bit(KEY_FLAG_NEGATIVE, &key->flags); |
| 560 | set_bit(KEY_FLAG_INSTANTIATED, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | now = current_kernel_time(); |
| 562 | key->expiry = now.tv_sec + timeout; |
David Howells | c08ef80 | 2009-09-14 17:26:13 +0100 | [diff] [blame] | 563 | key_schedule_gc(key->expiry + key_gc_delay); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 565 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | awaken = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | ret = 0; |
| 569 | |
| 570 | /* and link it into the destination keyring */ |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 571 | if (keyring && link_ret == 0) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 572 | __key_link(key, &edit); |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 573 | |
| 574 | /* disable the authorisation key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 575 | if (authkey) |
| 576 | key_revoke(authkey); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | } |
| 578 | |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 579 | mutex_unlock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | |
| 581 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 582 | __key_link_end(keyring, &key->index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | |
| 584 | /* wake up anyone waiting for a key to be constructed */ |
| 585 | if (awaken) |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 586 | wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 588 | return ret == 0 ? link_ret : ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 589 | } |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 590 | EXPORT_SYMBOL(key_reject_and_link); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 592 | /** |
| 593 | * key_put - Discard a reference to a key. |
| 594 | * @key: The key to discard a reference from. |
| 595 | * |
| 596 | * Discard a reference to a key, and when all the references are gone, we |
| 597 | * schedule the cleanup task to come and pull it out of the tree in process |
| 598 | * context at some later time. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | */ |
| 600 | void key_put(struct key *key) |
| 601 | { |
| 602 | if (key) { |
| 603 | key_check(key); |
| 604 | |
| 605 | if (atomic_dec_and_test(&key->usage)) |
Tejun Heo | 3b07e9c | 2012-08-20 14:51:24 -0700 | [diff] [blame] | 606 | schedule_work(&key_gc_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 608 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | EXPORT_SYMBOL(key_put); |
| 610 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 612 | * Find a key by its serial number. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | */ |
| 614 | struct key *key_lookup(key_serial_t id) |
| 615 | { |
| 616 | struct rb_node *n; |
| 617 | struct key *key; |
| 618 | |
| 619 | spin_lock(&key_serial_lock); |
| 620 | |
| 621 | /* search the tree for the specified key */ |
| 622 | n = key_serial_tree.rb_node; |
| 623 | while (n) { |
| 624 | key = rb_entry(n, struct key, serial_node); |
| 625 | |
| 626 | if (id < key->serial) |
| 627 | n = n->rb_left; |
| 628 | else if (id > key->serial) |
| 629 | n = n->rb_right; |
| 630 | else |
| 631 | goto found; |
| 632 | } |
| 633 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 634 | not_found: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | key = ERR_PTR(-ENOKEY); |
| 636 | goto error; |
| 637 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 638 | found: |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 639 | /* pretend it doesn't exist if it is awaiting deletion */ |
| 640 | if (atomic_read(&key->usage) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | goto not_found; |
| 642 | |
| 643 | /* this races with key_put(), but that doesn't matter since key_put() |
| 644 | * doesn't actually change the key |
| 645 | */ |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 646 | __key_get(key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 648 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 649 | spin_unlock(&key_serial_lock); |
| 650 | return key; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 651 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 654 | * Find and lock the specified key type against removal. |
| 655 | * |
| 656 | * We return with the sem read-locked if successful. If the type wasn't |
| 657 | * available -ENOKEY is returned instead. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | */ |
| 659 | struct key_type *key_type_lookup(const char *type) |
| 660 | { |
| 661 | struct key_type *ktype; |
| 662 | |
| 663 | down_read(&key_types_sem); |
| 664 | |
| 665 | /* look up the key type to see if it's one of the registered kernel |
| 666 | * types */ |
| 667 | list_for_each_entry(ktype, &key_types_list, link) { |
| 668 | if (strcmp(ktype->name, type) == 0) |
| 669 | goto found_kernel_type; |
| 670 | } |
| 671 | |
| 672 | up_read(&key_types_sem); |
| 673 | ktype = ERR_PTR(-ENOKEY); |
| 674 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 675 | found_kernel_type: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | return ktype; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 677 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 678 | |
Bryan Schumaker | 59e6b9c | 2012-02-24 14:14:50 -0500 | [diff] [blame] | 679 | void key_set_timeout(struct key *key, unsigned timeout) |
| 680 | { |
| 681 | struct timespec now; |
| 682 | time_t expiry = 0; |
| 683 | |
| 684 | /* make the changes with the locks held to prevent races */ |
| 685 | down_write(&key->sem); |
| 686 | |
| 687 | if (timeout > 0) { |
| 688 | now = current_kernel_time(); |
| 689 | expiry = now.tv_sec + timeout; |
| 690 | } |
| 691 | |
| 692 | key->expiry = expiry; |
| 693 | key_schedule_gc(key->expiry + key_gc_delay); |
| 694 | |
| 695 | up_write(&key->sem); |
| 696 | } |
| 697 | EXPORT_SYMBOL_GPL(key_set_timeout); |
| 698 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 700 | * Unlock a key type locked by key_type_lookup(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | */ |
| 702 | void key_type_put(struct key_type *ktype) |
| 703 | { |
| 704 | up_read(&key_types_sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 705 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 708 | * Attempt to update an existing key. |
| 709 | * |
| 710 | * The key is given to us with an incremented refcount that we need to discard |
| 711 | * if we get an error. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 713 | static inline key_ref_t __key_update(key_ref_t key_ref, |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 714 | struct key_preparsed_payload *prep) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 716 | struct key *key = key_ref_to_ptr(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | int ret; |
| 718 | |
| 719 | /* need write permission on the key to update it */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 720 | ret = key_permission(key_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 721 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | goto error; |
| 723 | |
| 724 | ret = -EEXIST; |
| 725 | if (!key->type->update) |
| 726 | goto error; |
| 727 | |
| 728 | down_write(&key->sem); |
| 729 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 730 | ret = key->type->update(key, prep); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 731 | if (ret == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | /* updating a negative key instantiates it */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 733 | clear_bit(KEY_FLAG_NEGATIVE, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | |
| 735 | up_write(&key->sem); |
| 736 | |
| 737 | if (ret < 0) |
| 738 | goto error; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 739 | out: |
| 740 | return key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 742 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | key_put(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 744 | key_ref = ERR_PTR(ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 745 | goto out; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 746 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 748 | /** |
| 749 | * key_create_or_update - Update or create and instantiate a key. |
| 750 | * @keyring_ref: A pointer to the destination keyring with possession flag. |
| 751 | * @type: The type of key. |
| 752 | * @description: The searchable description for the key. |
| 753 | * @payload: The data to use to instantiate or update the key. |
| 754 | * @plen: The length of @payload. |
| 755 | * @perm: The permissions mask for a new key. |
| 756 | * @flags: The quota flags for a new key. |
| 757 | * |
| 758 | * Search the destination keyring for a key of the same description and if one |
| 759 | * is found, update it, otherwise create and instantiate a new one and create a |
| 760 | * link to it from that keyring. |
| 761 | * |
| 762 | * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be |
| 763 | * concocted. |
| 764 | * |
| 765 | * Returns a pointer to the new key if successful, -ENODEV if the key type |
| 766 | * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the |
| 767 | * caller isn't permitted to modify the keyring or the LSM did not permit |
| 768 | * creation of the key. |
| 769 | * |
| 770 | * On success, the possession flag from the keyring ref will be tacked on to |
| 771 | * the key ref before it is returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 773 | key_ref_t key_create_or_update(key_ref_t keyring_ref, |
| 774 | const char *type, |
| 775 | const char *description, |
| 776 | const void *payload, |
| 777 | size_t plen, |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 778 | key_perm_t perm, |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 779 | unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | { |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 781 | struct keyring_index_key index_key = { |
| 782 | .description = description, |
| 783 | }; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 784 | struct key_preparsed_payload prep; |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 785 | struct assoc_array_edit *edit; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 786 | const struct cred *cred = current_cred(); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 787 | struct key *keyring, *key = NULL; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 788 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 789 | int ret; |
| 790 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | /* look up the key type to see if it's one of the registered kernel |
| 792 | * types */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 793 | index_key.type = key_type_lookup(type); |
| 794 | if (IS_ERR(index_key.type)) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 795 | key_ref = ERR_PTR(-ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | goto error; |
| 797 | } |
| 798 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 799 | key_ref = ERR_PTR(-EINVAL); |
David Howells | c06cfb0 | 2014-09-16 17:36:06 +0100 | [diff] [blame] | 800 | if (!index_key.type->instantiate || |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 801 | (!index_key.description && !index_key.type->preparse)) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 802 | goto error_put_type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 804 | keyring = key_ref_to_ptr(keyring_ref); |
| 805 | |
| 806 | key_check(keyring); |
| 807 | |
David Howells | c3a9d65 | 2006-04-10 15:15:21 +0100 | [diff] [blame] | 808 | key_ref = ERR_PTR(-ENOTDIR); |
| 809 | if (keyring->type != &key_type_keyring) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 810 | goto error_put_type; |
| 811 | |
| 812 | memset(&prep, 0, sizeof(prep)); |
| 813 | prep.data = payload; |
| 814 | prep.datalen = plen; |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 815 | prep.quotalen = index_key.type->def_datalen; |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 816 | prep.trusted = flags & KEY_ALLOC_TRUSTED; |
David Howells | 7dfa0ca6 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 817 | prep.expiry = TIME_T_MAX; |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 818 | if (index_key.type->preparse) { |
| 819 | ret = index_key.type->preparse(&prep); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 820 | if (ret < 0) { |
| 821 | key_ref = ERR_PTR(ret); |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 822 | goto error_free_prep; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 823 | } |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 824 | if (!index_key.description) |
| 825 | index_key.description = prep.description; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 826 | key_ref = ERR_PTR(-EINVAL); |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 827 | if (!index_key.description) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 828 | goto error_free_prep; |
| 829 | } |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 830 | index_key.desc_len = strlen(index_key.description); |
David Howells | c3a9d65 | 2006-04-10 15:15:21 +0100 | [diff] [blame] | 831 | |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 832 | key_ref = ERR_PTR(-EPERM); |
| 833 | if (!prep.trusted && test_bit(KEY_FLAG_TRUSTED_ONLY, &keyring->flags)) |
| 834 | goto error_free_prep; |
| 835 | flags |= prep.trusted ? KEY_ALLOC_TRUSTED : 0; |
| 836 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 837 | ret = __key_link_begin(keyring, &index_key, &edit); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 838 | if (ret < 0) { |
| 839 | key_ref = ERR_PTR(ret); |
| 840 | goto error_free_prep; |
| 841 | } |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 842 | |
| 843 | /* if we're going to allocate a new key, we're going to have |
| 844 | * to modify the keyring */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 845 | ret = key_permission(keyring_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 846 | if (ret < 0) { |
| 847 | key_ref = ERR_PTR(ret); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 848 | goto error_link_end; |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 849 | } |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 850 | |
David Howells | 1d9b7d9 | 2006-03-25 03:06:52 -0800 | [diff] [blame] | 851 | /* if it's possible to update this type of key, search for an existing |
| 852 | * key of the same type and description in the destination keyring and |
| 853 | * update that instead if possible |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 855 | if (index_key.type->update) { |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 856 | key_ref = find_key_to_update(keyring_ref, &index_key); |
| 857 | if (key_ref) |
David Howells | 1d9b7d9 | 2006-03-25 03:06:52 -0800 | [diff] [blame] | 858 | goto found_matching_key; |
| 859 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 860 | |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 861 | /* if the client doesn't provide, decide on the permissions we want */ |
| 862 | if (perm == KEY_PERM_UNDEF) { |
| 863 | perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 864 | perm |= KEY_USR_VIEW; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 866 | if (index_key.type->read) |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 867 | perm |= KEY_POS_READ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 868 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 869 | if (index_key.type == &key_type_keyring || |
| 870 | index_key.type->update) |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 871 | perm |= KEY_POS_WRITE; |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 872 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | |
| 874 | /* allocate a new key */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 875 | key = key_alloc(index_key.type, index_key.description, |
| 876 | cred->fsuid, cred->fsgid, cred, perm, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 877 | if (IS_ERR(key)) { |
David Howells | e231c2e | 2008-02-07 00:15:26 -0800 | [diff] [blame] | 878 | key_ref = ERR_CAST(key); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 879 | goto error_link_end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | } |
| 881 | |
| 882 | /* instantiate it and link it into the target keyring */ |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 883 | ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | if (ret < 0) { |
| 885 | key_put(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 886 | key_ref = ERR_PTR(ret); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 887 | goto error_link_end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 888 | } |
| 889 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 890 | key_ref = make_key_ref(key, is_key_possessed(keyring_ref)); |
| 891 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 892 | error_link_end: |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 893 | __key_link_end(keyring, &index_key, edit); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 894 | error_free_prep: |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 895 | if (index_key.type->preparse) |
| 896 | index_key.type->free_preparse(&prep); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 897 | error_put_type: |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 898 | key_type_put(index_key.type); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 899 | error: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 900 | return key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 901 | |
| 902 | found_matching_key: |
| 903 | /* we found a matching key, so we're going to try to update it |
| 904 | * - we can drop the locks first as we have the key pinned |
| 905 | */ |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 906 | __key_link_end(keyring, &index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 907 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 908 | key_ref = __key_update(key_ref, &prep); |
| 909 | goto error_free_prep; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 910 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 911 | EXPORT_SYMBOL(key_create_or_update); |
| 912 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 913 | /** |
| 914 | * key_update - Update a key's contents. |
| 915 | * @key_ref: The pointer (plus possession flag) to the key. |
| 916 | * @payload: The data to be used to update the key. |
| 917 | * @plen: The length of @payload. |
| 918 | * |
| 919 | * Attempt to update the contents of a key with the given payload data. The |
| 920 | * caller must be granted Write permission on the key. Negative keys can be |
| 921 | * instantiated by this method. |
| 922 | * |
| 923 | * Returns 0 on success, -EACCES if not permitted and -EOPNOTSUPP if the key |
| 924 | * type does not support updating. The key type may return other errors. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 925 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 926 | int key_update(key_ref_t key_ref, const void *payload, size_t plen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 927 | { |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 928 | struct key_preparsed_payload prep; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 929 | struct key *key = key_ref_to_ptr(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | int ret; |
| 931 | |
| 932 | key_check(key); |
| 933 | |
| 934 | /* the key must be writable */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 935 | ret = key_permission(key_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 936 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | goto error; |
| 938 | |
| 939 | /* attempt to update it if supported */ |
| 940 | ret = -EOPNOTSUPP; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 941 | if (!key->type->update) |
| 942 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 943 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 944 | memset(&prep, 0, sizeof(prep)); |
| 945 | prep.data = payload; |
| 946 | prep.datalen = plen; |
| 947 | prep.quotalen = key->type->def_datalen; |
David Howells | 7dfa0ca6 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 948 | prep.expiry = TIME_T_MAX; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 949 | if (key->type->preparse) { |
| 950 | ret = key->type->preparse(&prep); |
| 951 | if (ret < 0) |
| 952 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | } |
| 954 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 955 | down_write(&key->sem); |
| 956 | |
| 957 | ret = key->type->update(key, &prep); |
| 958 | if (ret == 0) |
| 959 | /* updating a negative key instantiates it */ |
| 960 | clear_bit(KEY_FLAG_NEGATIVE, &key->flags); |
| 961 | |
| 962 | up_write(&key->sem); |
| 963 | |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 964 | error: |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 965 | if (key->type->preparse) |
| 966 | key->type->free_preparse(&prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 967 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 968 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | EXPORT_SYMBOL(key_update); |
| 970 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 971 | /** |
| 972 | * key_revoke - Revoke a key. |
| 973 | * @key: The key to be revoked. |
| 974 | * |
| 975 | * Mark a key as being revoked and ask the type to free up its resources. The |
| 976 | * revocation timeout is set and the key and all its links will be |
| 977 | * automatically garbage collected after key_gc_delay amount of time if they |
| 978 | * are not manually dealt with first. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 979 | */ |
| 980 | void key_revoke(struct key *key) |
| 981 | { |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 982 | struct timespec now; |
| 983 | time_t time; |
| 984 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 985 | key_check(key); |
| 986 | |
David Howells | 76181c13 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 987 | /* make sure no one's trying to change or use the key when we mark it |
| 988 | * - we tell lockdep that we might nest because we might be revoking an |
| 989 | * authorisation key whilst holding the sem on a key we've just |
| 990 | * instantiated |
| 991 | */ |
| 992 | down_write_nested(&key->sem, 1); |
| 993 | if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) && |
| 994 | key->type->revoke) |
David Howells | 04c567d | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 995 | key->type->revoke(key); |
| 996 | |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 997 | /* set the death time to no more than the expiry time */ |
| 998 | now = current_kernel_time(); |
| 999 | time = now.tv_sec; |
| 1000 | if (key->revoked_at == 0 || key->revoked_at > time) { |
| 1001 | key->revoked_at = time; |
David Howells | c08ef80 | 2009-09-14 17:26:13 +0100 | [diff] [blame] | 1002 | key_schedule_gc(key->revoked_at + key_gc_delay); |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 1003 | } |
| 1004 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1005 | up_write(&key->sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1006 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1007 | EXPORT_SYMBOL(key_revoke); |
| 1008 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1009 | /** |
David Howells | fd75815 | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1010 | * key_invalidate - Invalidate a key. |
| 1011 | * @key: The key to be invalidated. |
| 1012 | * |
| 1013 | * Mark a key as being invalidated and have it cleaned up immediately. The key |
| 1014 | * is ignored by all searches and other operations from this point. |
| 1015 | */ |
| 1016 | void key_invalidate(struct key *key) |
| 1017 | { |
| 1018 | kenter("%d", key_serial(key)); |
| 1019 | |
| 1020 | key_check(key); |
| 1021 | |
| 1022 | if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) { |
| 1023 | down_write_nested(&key->sem, 1); |
| 1024 | if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) |
| 1025 | key_schedule_gc_links(); |
| 1026 | up_write(&key->sem); |
| 1027 | } |
| 1028 | } |
| 1029 | EXPORT_SYMBOL(key_invalidate); |
| 1030 | |
| 1031 | /** |
David Howells | 6a09d17 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1032 | * generic_key_instantiate - Simple instantiation of a key from preparsed data |
| 1033 | * @key: The key to be instantiated |
| 1034 | * @prep: The preparsed data to load. |
| 1035 | * |
| 1036 | * Instantiate a key from preparsed data. We assume we can just copy the data |
| 1037 | * in directly and clear the old pointers. |
| 1038 | * |
| 1039 | * This can be pointed to directly by the key type instantiate op pointer. |
| 1040 | */ |
| 1041 | int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep) |
| 1042 | { |
| 1043 | int ret; |
| 1044 | |
| 1045 | pr_devel("==>%s()\n", __func__); |
| 1046 | |
| 1047 | ret = key_payload_reserve(key, prep->quotalen); |
| 1048 | if (ret == 0) { |
| 1049 | key->type_data.p[0] = prep->type_data[0]; |
| 1050 | key->type_data.p[1] = prep->type_data[1]; |
David Howells | fc7c70e | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1051 | rcu_assign_keypointer(key, prep->payload[0]); |
| 1052 | key->payload.data2[1] = prep->payload[1]; |
David Howells | 6a09d17 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1053 | prep->type_data[0] = NULL; |
| 1054 | prep->type_data[1] = NULL; |
David Howells | fc7c70e | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1055 | prep->payload[0] = NULL; |
| 1056 | prep->payload[1] = NULL; |
David Howells | 6a09d17 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1057 | } |
| 1058 | pr_devel("<==%s() = %d\n", __func__, ret); |
| 1059 | return ret; |
| 1060 | } |
| 1061 | EXPORT_SYMBOL(generic_key_instantiate); |
| 1062 | |
| 1063 | /** |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1064 | * register_key_type - Register a type of key. |
| 1065 | * @ktype: The new key type. |
| 1066 | * |
| 1067 | * Register a new key type. |
| 1068 | * |
| 1069 | * Returns 0 on success or -EEXIST if a type of this name already exists. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | */ |
| 1071 | int register_key_type(struct key_type *ktype) |
| 1072 | { |
| 1073 | struct key_type *p; |
| 1074 | int ret; |
| 1075 | |
David Howells | 7845bc39 | 2011-11-16 11:15:54 +0000 | [diff] [blame] | 1076 | memset(&ktype->lock_class, 0, sizeof(ktype->lock_class)); |
| 1077 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | ret = -EEXIST; |
| 1079 | down_write(&key_types_sem); |
| 1080 | |
| 1081 | /* disallow key types with the same name */ |
| 1082 | list_for_each_entry(p, &key_types_list, link) { |
| 1083 | if (strcmp(p->name, ktype->name) == 0) |
| 1084 | goto out; |
| 1085 | } |
| 1086 | |
| 1087 | /* store the type */ |
| 1088 | list_add(&ktype->link, &key_types_list); |
David Howells | 1eb1bcf | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1089 | |
| 1090 | pr_notice("Key type %s registered\n", ktype->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1091 | ret = 0; |
| 1092 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1093 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1094 | up_write(&key_types_sem); |
| 1095 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1096 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1097 | EXPORT_SYMBOL(register_key_type); |
| 1098 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1099 | /** |
| 1100 | * unregister_key_type - Unregister a type of key. |
| 1101 | * @ktype: The key type. |
| 1102 | * |
| 1103 | * Unregister a key type and mark all the extant keys of this type as dead. |
| 1104 | * Those keys of this type are then destroyed to get rid of their payloads and |
| 1105 | * they and their links will be garbage collected as soon as possible. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1106 | */ |
| 1107 | void unregister_key_type(struct key_type *ktype) |
| 1108 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1109 | down_write(&key_types_sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1110 | list_del_init(&ktype->link); |
David Howells | 0c061b5 | 2011-08-22 14:09:36 +0100 | [diff] [blame] | 1111 | downgrade_write(&key_types_sem); |
| 1112 | key_gc_keytype(ktype); |
David Howells | 1eb1bcf | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1113 | pr_notice("Key type %s unregistered\n", ktype->name); |
David Howells | 0c061b5 | 2011-08-22 14:09:36 +0100 | [diff] [blame] | 1114 | up_read(&key_types_sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1115 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1116 | EXPORT_SYMBOL(unregister_key_type); |
| 1117 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1118 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1119 | * Initialise the key management state. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1120 | */ |
| 1121 | void __init key_init(void) |
| 1122 | { |
| 1123 | /* allocate a slab in which we can store keys */ |
| 1124 | key_jar = kmem_cache_create("key_jar", sizeof(struct key), |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 1125 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1126 | |
| 1127 | /* add the special key types */ |
| 1128 | list_add_tail(&key_type_keyring.link, &key_types_list); |
| 1129 | list_add_tail(&key_type_dead.link, &key_types_list); |
| 1130 | list_add_tail(&key_type_user.link, &key_types_list); |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 1131 | list_add_tail(&key_type_logon.link, &key_types_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1132 | |
| 1133 | /* record the root user tracking */ |
| 1134 | rb_link_node(&root_key_user.node, |
| 1135 | NULL, |
| 1136 | &key_user_tree.rb_node); |
| 1137 | |
| 1138 | rb_insert_color(&root_key_user.node, |
| 1139 | &key_user_tree); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1140 | } |