David Howells | 76181c1 | 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 | 76181c1 | 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 | 76181c1 | 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. |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 204 | * @restrict_link: Optional link restriction method for new keyrings. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 205 | * |
| 206 | * Allocate a key of the specified type with the attributes given. The key is |
| 207 | * returned in an uninstantiated state and the caller needs to instantiate the |
| 208 | * key before returning. |
| 209 | * |
| 210 | * The user's key count quota is updated to reflect the creation of the key and |
| 211 | * the user's key data quota has the default for the key type reserved. The |
| 212 | * instantiation function should amend this as necessary. If insufficient |
| 213 | * quota is available, -EDQUOT will be returned. |
| 214 | * |
| 215 | * The LSM security modules can prevent a key being created, in which case |
| 216 | * -EACCES will be returned. |
| 217 | * |
| 218 | * Returns a pointer to the new key if successful and an error code otherwise. |
| 219 | * |
| 220 | * Note that the caller needs to ensure the key type isn't uninstantiated. |
| 221 | * Internally this can be done by locking key_types_sem. Externally, this can |
| 222 | * be done by either never unregistering the key type, or making sure |
| 223 | * key_alloc() calls don't race with module unloading. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | */ |
| 225 | struct key *key_alloc(struct key_type *type, const char *desc, |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 226 | kuid_t uid, kgid_t gid, const struct cred *cred, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 227 | key_perm_t perm, unsigned long flags, |
| 228 | int (*restrict_link)(struct key *, |
| 229 | const struct key_type *, |
| 230 | unsigned long, |
| 231 | const union key_payload *)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | { |
| 233 | struct key_user *user = NULL; |
| 234 | struct key *key; |
| 235 | size_t desclen, quotalen; |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 236 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | |
| 238 | key = ERR_PTR(-EINVAL); |
| 239 | if (!desc || !*desc) |
| 240 | goto error; |
| 241 | |
David Howells | b9fffa3 | 2011-03-07 15:05:59 +0000 | [diff] [blame] | 242 | if (type->vet_description) { |
| 243 | ret = type->vet_description(desc); |
| 244 | if (ret < 0) { |
| 245 | key = ERR_PTR(ret); |
| 246 | goto error; |
| 247 | } |
| 248 | } |
| 249 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 250 | desclen = strlen(desc); |
| 251 | quotalen = desclen + 1 + type->def_datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | |
| 253 | /* get hold of the key tracking for this user */ |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 254 | user = key_user_lookup(uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | if (!user) |
| 256 | goto no_memory_1; |
| 257 | |
| 258 | /* check that the user's quota permits allocation of another key and |
| 259 | * its description */ |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 260 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 261 | unsigned maxkeys = uid_eq(uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 262 | key_quota_root_maxkeys : key_quota_maxkeys; |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 263 | unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 264 | key_quota_root_maxbytes : key_quota_maxbytes; |
| 265 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | spin_lock(&user->lock); |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 267 | if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 268 | if (user->qnkeys + 1 >= maxkeys || |
| 269 | user->qnbytes + quotalen >= maxbytes || |
| 270 | user->qnbytes + quotalen < user->qnbytes) |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 271 | goto no_quota; |
| 272 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | |
| 274 | user->qnkeys++; |
| 275 | user->qnbytes += quotalen; |
| 276 | spin_unlock(&user->lock); |
| 277 | } |
| 278 | |
| 279 | /* allocate and initialise the key and its description */ |
David Howells | 2480f57 | 2013-12-02 11:24:18 +0000 | [diff] [blame] | 280 | key = kmem_cache_zalloc(key_jar, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | if (!key) |
| 282 | goto no_memory_2; |
| 283 | |
Dan Carpenter | 5057975 | 2014-12-11 19:59:38 +0000 | [diff] [blame] | 284 | key->index_key.desc_len = desclen; |
| 285 | key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL); |
Insu Yun | 27720e7 | 2015-10-21 14:04:47 +0100 | [diff] [blame] | 286 | if (!key->index_key.description) |
Dan Carpenter | 5057975 | 2014-12-11 19:59:38 +0000 | [diff] [blame] | 287 | goto no_memory_3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | |
| 289 | atomic_set(&key->usage, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 290 | init_rwsem(&key->sem); |
David Howells | 7845bc39 | 2011-11-16 11:15:54 +0000 | [diff] [blame] | 291 | lockdep_set_class(&key->sem, &type->lock_class); |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 292 | key->index_key.type = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | key->user = user; |
| 294 | key->quotalen = quotalen; |
| 295 | key->datalen = type->def_datalen; |
| 296 | key->uid = uid; |
| 297 | key->gid = gid; |
| 298 | key->perm = perm; |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 299 | key->restrict_link = restrict_link; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 301 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 302 | key->flags |= 1 << KEY_FLAG_IN_QUOTA; |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 303 | if (flags & KEY_ALLOC_TRUSTED) |
| 304 | key->flags |= 1 << KEY_FLAG_TRUSTED; |
David Howells | 5d2787c | 2016-02-09 16:40:46 +0000 | [diff] [blame] | 305 | if (flags & KEY_ALLOC_BUILT_IN) |
| 306 | key->flags |= 1 << KEY_FLAG_BUILTIN; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | #ifdef KEY_DEBUGGING |
| 309 | key->magic = KEY_DEBUG_MAGIC; |
| 310 | #endif |
| 311 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 312 | /* let the security module know about the key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 313 | ret = security_key_alloc(key, cred, flags); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 314 | if (ret < 0) |
| 315 | goto security_error; |
| 316 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | /* publish the key by giving it a serial number */ |
| 318 | atomic_inc(&user->nkeys); |
| 319 | key_alloc_serial(key); |
| 320 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 321 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | return key; |
| 323 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 324 | security_error: |
| 325 | kfree(key->description); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | kmem_cache_free(key_jar, key); |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 327 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | spin_lock(&user->lock); |
| 329 | user->qnkeys--; |
| 330 | user->qnbytes -= quotalen; |
| 331 | spin_unlock(&user->lock); |
| 332 | } |
| 333 | key_user_put(user); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 334 | key = ERR_PTR(ret); |
| 335 | goto error; |
| 336 | |
| 337 | no_memory_3: |
| 338 | kmem_cache_free(key_jar, key); |
| 339 | no_memory_2: |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 340 | if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) { |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 341 | spin_lock(&user->lock); |
| 342 | user->qnkeys--; |
| 343 | user->qnbytes -= quotalen; |
| 344 | spin_unlock(&user->lock); |
| 345 | } |
| 346 | key_user_put(user); |
| 347 | no_memory_1: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | key = ERR_PTR(-ENOMEM); |
| 349 | goto error; |
| 350 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 351 | no_quota: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | spin_unlock(&user->lock); |
| 353 | key_user_put(user); |
| 354 | key = ERR_PTR(-EDQUOT); |
| 355 | goto error; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 356 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | EXPORT_SYMBOL(key_alloc); |
| 358 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 359 | /** |
| 360 | * key_payload_reserve - Adjust data quota reservation for the key's payload |
| 361 | * @key: The key to make the reservation for. |
| 362 | * @datalen: The amount of data payload the caller now wants. |
| 363 | * |
| 364 | * Adjust the amount of the owning user's key data quota that a key reserves. |
| 365 | * If the amount is increased, then -EDQUOT may be returned if there isn't |
| 366 | * enough free quota available. |
| 367 | * |
| 368 | * If successful, 0 is returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | */ |
| 370 | int key_payload_reserve(struct key *key, size_t datalen) |
| 371 | { |
Justin P. Mattock | c5b60b5 | 2010-04-21 00:02:11 -0700 | [diff] [blame] | 372 | int delta = (int)datalen - key->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | int ret = 0; |
| 374 | |
| 375 | key_check(key); |
| 376 | |
| 377 | /* contemplate the quota adjustment */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 378 | if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) { |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 379 | unsigned maxbytes = uid_eq(key->user->uid, GLOBAL_ROOT_UID) ? |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 380 | key_quota_root_maxbytes : key_quota_maxbytes; |
| 381 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | spin_lock(&key->user->lock); |
| 383 | |
| 384 | if (delta > 0 && |
David Howells | 0b77f5b | 2008-04-29 01:01:32 -0700 | [diff] [blame] | 385 | (key->user->qnbytes + delta >= maxbytes || |
| 386 | key->user->qnbytes + delta < key->user->qnbytes)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | ret = -EDQUOT; |
| 388 | } |
| 389 | else { |
| 390 | key->user->qnbytes += delta; |
| 391 | key->quotalen += delta; |
| 392 | } |
| 393 | spin_unlock(&key->user->lock); |
| 394 | } |
| 395 | |
| 396 | /* change the recorded data length if that didn't generate an error */ |
| 397 | if (ret == 0) |
| 398 | key->datalen = datalen; |
| 399 | |
| 400 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 401 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | EXPORT_SYMBOL(key_payload_reserve); |
| 403 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 405 | * Instantiate a key and link it into the target keyring atomically. Must be |
| 406 | * called with the target keyring's semaphore writelocked. The target key's |
| 407 | * semaphore need not be locked as instantiation is serialised by |
| 408 | * key_construction_mutex. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | */ |
| 410 | static int __key_instantiate_and_link(struct key *key, |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 411 | struct key_preparsed_payload *prep, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 412 | struct key *keyring, |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 413 | struct key *authkey, |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 414 | struct assoc_array_edit **_edit) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | { |
| 416 | int ret, awaken; |
| 417 | |
| 418 | key_check(key); |
| 419 | key_check(keyring); |
| 420 | |
| 421 | awaken = 0; |
| 422 | ret = -EBUSY; |
| 423 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 424 | mutex_lock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | |
| 426 | /* can't instantiate twice */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 427 | if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | /* instantiate the key */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 429 | ret = key->type->instantiate(key, prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | |
| 431 | if (ret == 0) { |
| 432 | /* mark the key as being instantiated */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | atomic_inc(&key->user->nikeys); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 434 | set_bit(KEY_FLAG_INSTANTIATED, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 436 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | awaken = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | |
| 439 | /* and link it into the destination keyring */ |
Mimi Zohar | d3600bc | 2015-11-10 08:34:46 -0500 | [diff] [blame] | 440 | if (keyring) { |
David Howells | eee0450 | 2016-01-27 01:02:03 +0000 | [diff] [blame] | 441 | if (test_bit(KEY_FLAG_KEEP, &keyring->flags)) |
| 442 | set_bit(KEY_FLAG_KEEP, &key->flags); |
Mimi Zohar | d3600bc | 2015-11-10 08:34:46 -0500 | [diff] [blame] | 443 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 444 | __key_link(key, _edit); |
Mimi Zohar | d3600bc | 2015-11-10 08:34:46 -0500 | [diff] [blame] | 445 | } |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 446 | |
| 447 | /* disable the authorisation key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 448 | if (authkey) |
| 449 | key_revoke(authkey); |
David Howells | 7dfa0ca | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 450 | |
| 451 | if (prep->expiry != TIME_T_MAX) { |
| 452 | key->expiry = prep->expiry; |
| 453 | key_schedule_gc(prep->expiry + key_gc_delay); |
| 454 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | } |
| 456 | } |
| 457 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 458 | mutex_unlock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | |
| 460 | /* wake up anyone waiting for a key to be constructed */ |
| 461 | if (awaken) |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 462 | wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | |
| 464 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 465 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 467 | /** |
| 468 | * key_instantiate_and_link - Instantiate a key and link it into the keyring. |
| 469 | * @key: The key to instantiate. |
| 470 | * @data: The data to use to instantiate the keyring. |
| 471 | * @datalen: The length of @data. |
| 472 | * @keyring: Keyring to create a link in on success (or NULL). |
| 473 | * @authkey: The authorisation token permitting instantiation. |
| 474 | * |
| 475 | * Instantiate a key that's in the uninstantiated state using the provided data |
| 476 | * and, if successful, link it in to the destination keyring if one is |
| 477 | * supplied. |
| 478 | * |
| 479 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
| 480 | * waiting for the key is woken up. If the key was already instantiated, |
| 481 | * -EBUSY will be returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | */ |
| 483 | int key_instantiate_and_link(struct key *key, |
| 484 | const void *data, |
| 485 | size_t datalen, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 486 | struct key *keyring, |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 487 | struct key *authkey) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | { |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 489 | struct key_preparsed_payload prep; |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 490 | struct assoc_array_edit *edit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | int ret; |
| 492 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 493 | memset(&prep, 0, sizeof(prep)); |
| 494 | prep.data = data; |
| 495 | prep.datalen = datalen; |
| 496 | prep.quotalen = key->type->def_datalen; |
David Howells | 7dfa0ca | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 497 | prep.expiry = TIME_T_MAX; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 498 | if (key->type->preparse) { |
| 499 | ret = key->type->preparse(&prep); |
| 500 | if (ret < 0) |
| 501 | goto error; |
| 502 | } |
| 503 | |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 504 | if (keyring) { |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 505 | if (keyring->restrict_link) { |
| 506 | ret = keyring->restrict_link(keyring, key->type, |
| 507 | key->flags, &prep.payload); |
| 508 | if (ret < 0) |
| 509 | goto error; |
| 510 | } |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 511 | ret = __key_link_begin(keyring, &key->index_key, &edit); |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 512 | if (ret < 0) |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 513 | goto error; |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 514 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 516 | ret = __key_instantiate_and_link(key, &prep, keyring, authkey, &edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | |
| 518 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 519 | __key_link_end(keyring, &key->index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 521 | error: |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 522 | if (key->type->preparse) |
| 523 | key->type->free_preparse(&prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 525 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | |
| 527 | EXPORT_SYMBOL(key_instantiate_and_link); |
| 528 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 529 | /** |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 530 | * 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] | 531 | * @key: The key to instantiate. |
| 532 | * @timeout: The timeout on the negative key. |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 533 | * @error: The error to return when the key is hit. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 534 | * @keyring: Keyring to create a link in on success (or NULL). |
| 535 | * @authkey: The authorisation token permitting instantiation. |
| 536 | * |
| 537 | * Negatively instantiate a key that's in the uninstantiated state and, if |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 538 | * successful, set its timeout and stored error and link it in to the |
| 539 | * destination keyring if one is supplied. The key and any links to the key |
| 540 | * will be automatically garbage collected after the timeout expires. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 541 | * |
| 542 | * 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] | 543 | * them to return the stored error code (typically ENOKEY) until the negative |
| 544 | * key expires. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 545 | * |
| 546 | * If successful, 0 is returned, the authorisation token is revoked and anyone |
| 547 | * waiting for the key is woken up. If the key was already instantiated, |
| 548 | * -EBUSY will be returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | */ |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 550 | int key_reject_and_link(struct key *key, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | unsigned timeout, |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 552 | unsigned error, |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 553 | struct key *keyring, |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 554 | struct key *authkey) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | { |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 556 | struct assoc_array_edit *edit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | struct timespec now; |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 558 | int ret, awaken, link_ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | |
| 560 | key_check(key); |
| 561 | key_check(keyring); |
| 562 | |
| 563 | awaken = 0; |
| 564 | ret = -EBUSY; |
| 565 | |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 566 | if (keyring) { |
| 567 | if (keyring->restrict_link) |
| 568 | return -EPERM; |
| 569 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 570 | link_ret = __key_link_begin(keyring, &key->index_key, &edit); |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 571 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 573 | mutex_lock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | |
| 575 | /* can't instantiate twice */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 576 | if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | /* mark the key as being negatively instantiated */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | atomic_inc(&key->user->nikeys); |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 579 | key->reject_error = -error; |
David Howells | 74792b0 | 2013-10-30 11:15:24 +0000 | [diff] [blame] | 580 | smp_wmb(); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 581 | set_bit(KEY_FLAG_NEGATIVE, &key->flags); |
| 582 | set_bit(KEY_FLAG_INSTANTIATED, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | now = current_kernel_time(); |
| 584 | key->expiry = now.tv_sec + timeout; |
David Howells | c08ef80 | 2009-09-14 17:26:13 +0100 | [diff] [blame] | 585 | key_schedule_gc(key->expiry + key_gc_delay); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 587 | if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | awaken = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | ret = 0; |
| 591 | |
| 592 | /* and link it into the destination keyring */ |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 593 | if (keyring && link_ret == 0) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 594 | __key_link(key, &edit); |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 595 | |
| 596 | /* disable the authorisation key */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 597 | if (authkey) |
| 598 | key_revoke(authkey); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | } |
| 600 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 601 | mutex_unlock(&key_construction_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | |
| 603 | if (keyring) |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 604 | __key_link_end(keyring, &key->index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | |
| 606 | /* wake up anyone waiting for a key to be constructed */ |
| 607 | if (awaken) |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 608 | wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | |
David Howells | f70e2e0 | 2010-04-30 14:32:39 +0100 | [diff] [blame] | 610 | return ret == 0 ? link_ret : ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 611 | } |
David Howells | fdd1b94 | 2011-03-07 15:06:09 +0000 | [diff] [blame] | 612 | EXPORT_SYMBOL(key_reject_and_link); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 614 | /** |
| 615 | * key_put - Discard a reference to a key. |
| 616 | * @key: The key to discard a reference from. |
| 617 | * |
| 618 | * Discard a reference to a key, and when all the references are gone, we |
| 619 | * schedule the cleanup task to come and pull it out of the tree in process |
| 620 | * context at some later time. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | */ |
| 622 | void key_put(struct key *key) |
| 623 | { |
| 624 | if (key) { |
| 625 | key_check(key); |
| 626 | |
| 627 | if (atomic_dec_and_test(&key->usage)) |
Tejun Heo | 3b07e9c | 2012-08-20 14:51:24 -0700 | [diff] [blame] | 628 | schedule_work(&key_gc_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 630 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | EXPORT_SYMBOL(key_put); |
| 632 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 633 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 634 | * Find a key by its serial number. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | */ |
| 636 | struct key *key_lookup(key_serial_t id) |
| 637 | { |
| 638 | struct rb_node *n; |
| 639 | struct key *key; |
| 640 | |
| 641 | spin_lock(&key_serial_lock); |
| 642 | |
| 643 | /* search the tree for the specified key */ |
| 644 | n = key_serial_tree.rb_node; |
| 645 | while (n) { |
| 646 | key = rb_entry(n, struct key, serial_node); |
| 647 | |
| 648 | if (id < key->serial) |
| 649 | n = n->rb_left; |
| 650 | else if (id > key->serial) |
| 651 | n = n->rb_right; |
| 652 | else |
| 653 | goto found; |
| 654 | } |
| 655 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 656 | not_found: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | key = ERR_PTR(-ENOKEY); |
| 658 | goto error; |
| 659 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 660 | found: |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 661 | /* pretend it doesn't exist if it is awaiting deletion */ |
| 662 | if (atomic_read(&key->usage) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | goto not_found; |
| 664 | |
| 665 | /* this races with key_put(), but that doesn't matter since key_put() |
| 666 | * doesn't actually change the key |
| 667 | */ |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 668 | __key_get(key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 670 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | spin_unlock(&key_serial_lock); |
| 672 | return key; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 673 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 676 | * Find and lock the specified key type against removal. |
| 677 | * |
| 678 | * We return with the sem read-locked if successful. If the type wasn't |
| 679 | * available -ENOKEY is returned instead. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | */ |
| 681 | struct key_type *key_type_lookup(const char *type) |
| 682 | { |
| 683 | struct key_type *ktype; |
| 684 | |
| 685 | down_read(&key_types_sem); |
| 686 | |
| 687 | /* look up the key type to see if it's one of the registered kernel |
| 688 | * types */ |
| 689 | list_for_each_entry(ktype, &key_types_list, link) { |
| 690 | if (strcmp(ktype->name, type) == 0) |
| 691 | goto found_kernel_type; |
| 692 | } |
| 693 | |
| 694 | up_read(&key_types_sem); |
| 695 | ktype = ERR_PTR(-ENOKEY); |
| 696 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 697 | found_kernel_type: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | return ktype; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 699 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | |
Bryan Schumaker | 59e6b9c | 2012-02-24 14:14:50 -0500 | [diff] [blame] | 701 | void key_set_timeout(struct key *key, unsigned timeout) |
| 702 | { |
| 703 | struct timespec now; |
| 704 | time_t expiry = 0; |
| 705 | |
| 706 | /* make the changes with the locks held to prevent races */ |
| 707 | down_write(&key->sem); |
| 708 | |
| 709 | if (timeout > 0) { |
| 710 | now = current_kernel_time(); |
| 711 | expiry = now.tv_sec + timeout; |
| 712 | } |
| 713 | |
| 714 | key->expiry = expiry; |
| 715 | key_schedule_gc(key->expiry + key_gc_delay); |
| 716 | |
| 717 | up_write(&key->sem); |
| 718 | } |
| 719 | EXPORT_SYMBOL_GPL(key_set_timeout); |
| 720 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 722 | * Unlock a key type locked by key_type_lookup(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 723 | */ |
| 724 | void key_type_put(struct key_type *ktype) |
| 725 | { |
| 726 | up_read(&key_types_sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 727 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 728 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 730 | * Attempt to update an existing key. |
| 731 | * |
| 732 | * The key is given to us with an incremented refcount that we need to discard |
| 733 | * if we get an error. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 735 | static inline key_ref_t __key_update(key_ref_t key_ref, |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 736 | struct key_preparsed_payload *prep) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 738 | struct key *key = key_ref_to_ptr(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | int ret; |
| 740 | |
| 741 | /* need write permission on the key to update it */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 742 | ret = key_permission(key_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 743 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | goto error; |
| 745 | |
| 746 | ret = -EEXIST; |
| 747 | if (!key->type->update) |
| 748 | goto error; |
| 749 | |
| 750 | down_write(&key->sem); |
| 751 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 752 | ret = key->type->update(key, prep); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 753 | if (ret == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | /* updating a negative key instantiates it */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 755 | clear_bit(KEY_FLAG_NEGATIVE, &key->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | |
| 757 | up_write(&key->sem); |
| 758 | |
| 759 | if (ret < 0) |
| 760 | goto error; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 761 | out: |
| 762 | return key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 764 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | key_put(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 766 | key_ref = ERR_PTR(ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | goto out; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 768 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 770 | /** |
| 771 | * key_create_or_update - Update or create and instantiate a key. |
| 772 | * @keyring_ref: A pointer to the destination keyring with possession flag. |
| 773 | * @type: The type of key. |
| 774 | * @description: The searchable description for the key. |
| 775 | * @payload: The data to use to instantiate or update the key. |
| 776 | * @plen: The length of @payload. |
| 777 | * @perm: The permissions mask for a new key. |
| 778 | * @flags: The quota flags for a new key. |
| 779 | * |
| 780 | * Search the destination keyring for a key of the same description and if one |
| 781 | * is found, update it, otherwise create and instantiate a new one and create a |
| 782 | * link to it from that keyring. |
| 783 | * |
| 784 | * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be |
| 785 | * concocted. |
| 786 | * |
| 787 | * Returns a pointer to the new key if successful, -ENODEV if the key type |
| 788 | * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the |
| 789 | * caller isn't permitted to modify the keyring or the LSM did not permit |
| 790 | * creation of the key. |
| 791 | * |
| 792 | * On success, the possession flag from the keyring ref will be tacked on to |
| 793 | * the key ref before it is returned. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 794 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 795 | key_ref_t key_create_or_update(key_ref_t keyring_ref, |
| 796 | const char *type, |
| 797 | const char *description, |
| 798 | const void *payload, |
| 799 | size_t plen, |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 800 | key_perm_t perm, |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 801 | unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | { |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 803 | struct keyring_index_key index_key = { |
| 804 | .description = description, |
| 805 | }; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 806 | struct key_preparsed_payload prep; |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 807 | struct assoc_array_edit *edit; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 808 | const struct cred *cred = current_cred(); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 809 | struct key *keyring, *key = NULL; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 810 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | int ret; |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 812 | int (*restrict_link)(struct key *, |
| 813 | const struct key_type *, |
| 814 | unsigned long, |
| 815 | const union key_payload *) = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | /* look up the key type to see if it's one of the registered kernel |
| 818 | * types */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 819 | index_key.type = key_type_lookup(type); |
| 820 | if (IS_ERR(index_key.type)) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 821 | key_ref = ERR_PTR(-ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | goto error; |
| 823 | } |
| 824 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 825 | key_ref = ERR_PTR(-EINVAL); |
David Howells | c06cfb0 | 2014-09-16 17:36:06 +0100 | [diff] [blame] | 826 | if (!index_key.type->instantiate || |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 827 | (!index_key.description && !index_key.type->preparse)) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 828 | goto error_put_type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 830 | keyring = key_ref_to_ptr(keyring_ref); |
| 831 | |
| 832 | key_check(keyring); |
| 833 | |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 834 | key_ref = ERR_PTR(-EPERM); |
| 835 | if (!(flags & KEY_ALLOC_BYPASS_RESTRICTION)) |
| 836 | restrict_link = keyring->restrict_link; |
| 837 | |
David Howells | c3a9d65 | 2006-04-10 15:15:21 +0100 | [diff] [blame] | 838 | key_ref = ERR_PTR(-ENOTDIR); |
| 839 | if (keyring->type != &key_type_keyring) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 840 | goto error_put_type; |
| 841 | |
| 842 | memset(&prep, 0, sizeof(prep)); |
| 843 | prep.data = payload; |
| 844 | prep.datalen = plen; |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 845 | prep.quotalen = index_key.type->def_datalen; |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 846 | prep.trusted = flags & KEY_ALLOC_TRUSTED; |
David Howells | 7dfa0ca | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 847 | prep.expiry = TIME_T_MAX; |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 848 | if (index_key.type->preparse) { |
| 849 | ret = index_key.type->preparse(&prep); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 850 | if (ret < 0) { |
| 851 | key_ref = ERR_PTR(ret); |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 852 | goto error_free_prep; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 853 | } |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 854 | if (!index_key.description) |
| 855 | index_key.description = prep.description; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 856 | key_ref = ERR_PTR(-EINVAL); |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 857 | if (!index_key.description) |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 858 | goto error_free_prep; |
| 859 | } |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 860 | index_key.desc_len = strlen(index_key.description); |
David Howells | c3a9d65 | 2006-04-10 15:15:21 +0100 | [diff] [blame] | 861 | |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 862 | if (restrict_link) { |
| 863 | unsigned long kflags = prep.trusted ? KEY_FLAG_TRUSTED : 0; |
| 864 | ret = restrict_link(keyring, |
| 865 | index_key.type, kflags, &prep.payload); |
| 866 | if (ret < 0) { |
| 867 | key_ref = ERR_PTR(ret); |
| 868 | goto error_free_prep; |
| 869 | } |
| 870 | } |
David Howells | 008643b | 2013-08-30 16:07:37 +0100 | [diff] [blame] | 871 | |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 872 | ret = __key_link_begin(keyring, &index_key, &edit); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 873 | if (ret < 0) { |
| 874 | key_ref = ERR_PTR(ret); |
| 875 | goto error_free_prep; |
| 876 | } |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 877 | |
| 878 | /* if we're going to allocate a new key, we're going to have |
| 879 | * to modify the keyring */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 880 | ret = key_permission(keyring_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 881 | if (ret < 0) { |
| 882 | key_ref = ERR_PTR(ret); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 883 | goto error_link_end; |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 884 | } |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 885 | |
David Howells | 1d9b7d9 | 2006-03-25 03:06:52 -0800 | [diff] [blame] | 886 | /* if it's possible to update this type of key, search for an existing |
| 887 | * key of the same type and description in the destination keyring and |
| 888 | * update that instead if possible |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 889 | */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 890 | if (index_key.type->update) { |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 891 | key_ref = find_key_to_update(keyring_ref, &index_key); |
| 892 | if (key_ref) |
David Howells | 1d9b7d9 | 2006-03-25 03:06:52 -0800 | [diff] [blame] | 893 | goto found_matching_key; |
| 894 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 896 | /* if the client doesn't provide, decide on the permissions we want */ |
| 897 | if (perm == KEY_PERM_UNDEF) { |
| 898 | 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] | 899 | perm |= KEY_USR_VIEW; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 900 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 901 | if (index_key.type->read) |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 902 | perm |= KEY_POS_READ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 903 | |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 904 | if (index_key.type == &key_type_keyring || |
| 905 | index_key.type->update) |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 906 | perm |= KEY_POS_WRITE; |
Arun Raghavan | 6b79ccb | 2008-04-29 01:01:28 -0700 | [diff] [blame] | 907 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | |
| 909 | /* allocate a new key */ |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 910 | key = key_alloc(index_key.type, index_key.description, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame^] | 911 | cred->fsuid, cred->fsgid, cred, perm, flags, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | if (IS_ERR(key)) { |
David Howells | e231c2e | 2008-02-07 00:15:26 -0800 | [diff] [blame] | 913 | key_ref = ERR_CAST(key); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 914 | goto error_link_end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | } |
| 916 | |
| 917 | /* instantiate it and link it into the target keyring */ |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 918 | ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 919 | if (ret < 0) { |
| 920 | key_put(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 921 | key_ref = ERR_PTR(ret); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 922 | goto error_link_end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 923 | } |
| 924 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 925 | key_ref = make_key_ref(key, is_key_possessed(keyring_ref)); |
| 926 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 927 | error_link_end: |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 928 | __key_link_end(keyring, &index_key, edit); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 929 | error_free_prep: |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 930 | if (index_key.type->preparse) |
| 931 | index_key.type->free_preparse(&prep); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 932 | error_put_type: |
David Howells | 16feef4 | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 933 | key_type_put(index_key.type); |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 934 | error: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 935 | return key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | |
| 937 | found_matching_key: |
| 938 | /* we found a matching key, so we're going to try to update it |
| 939 | * - we can drop the locks first as we have the key pinned |
| 940 | */ |
David Howells | b2a4df2 | 2013-09-24 10:35:18 +0100 | [diff] [blame] | 941 | __key_link_end(keyring, &index_key, edit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 943 | key_ref = __key_update(key_ref, &prep); |
| 944 | goto error_free_prep; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 945 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 946 | EXPORT_SYMBOL(key_create_or_update); |
| 947 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 948 | /** |
| 949 | * key_update - Update a key's contents. |
| 950 | * @key_ref: The pointer (plus possession flag) to the key. |
| 951 | * @payload: The data to be used to update the key. |
| 952 | * @plen: The length of @payload. |
| 953 | * |
| 954 | * Attempt to update the contents of a key with the given payload data. The |
| 955 | * caller must be granted Write permission on the key. Negative keys can be |
| 956 | * instantiated by this method. |
| 957 | * |
| 958 | * Returns 0 on success, -EACCES if not permitted and -EOPNOTSUPP if the key |
| 959 | * type does not support updating. The key type may return other errors. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 960 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 961 | 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] | 962 | { |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 963 | struct key_preparsed_payload prep; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 964 | struct key *key = key_ref_to_ptr(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 965 | int ret; |
| 966 | |
| 967 | key_check(key); |
| 968 | |
| 969 | /* the key must be writable */ |
David Howells | f589594 | 2014-03-14 17:44:49 +0000 | [diff] [blame] | 970 | ret = key_permission(key_ref, KEY_NEED_WRITE); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 971 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 972 | goto error; |
| 973 | |
| 974 | /* attempt to update it if supported */ |
| 975 | ret = -EOPNOTSUPP; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 976 | if (!key->type->update) |
| 977 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 978 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 979 | memset(&prep, 0, sizeof(prep)); |
| 980 | prep.data = payload; |
| 981 | prep.datalen = plen; |
| 982 | prep.quotalen = key->type->def_datalen; |
David Howells | 7dfa0ca | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 983 | prep.expiry = TIME_T_MAX; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 984 | if (key->type->preparse) { |
| 985 | ret = key->type->preparse(&prep); |
| 986 | if (ret < 0) |
| 987 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 988 | } |
| 989 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 990 | down_write(&key->sem); |
| 991 | |
| 992 | ret = key->type->update(key, &prep); |
| 993 | if (ret == 0) |
| 994 | /* updating a negative key instantiates it */ |
| 995 | clear_bit(KEY_FLAG_NEGATIVE, &key->flags); |
| 996 | |
| 997 | up_write(&key->sem); |
| 998 | |
David Howells | 4d8c025 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 999 | error: |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 1000 | if (key->type->preparse) |
| 1001 | key->type->free_preparse(&prep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1003 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1004 | EXPORT_SYMBOL(key_update); |
| 1005 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1006 | /** |
| 1007 | * key_revoke - Revoke a key. |
| 1008 | * @key: The key to be revoked. |
| 1009 | * |
| 1010 | * Mark a key as being revoked and ask the type to free up its resources. The |
| 1011 | * revocation timeout is set and the key and all its links will be |
| 1012 | * automatically garbage collected after key_gc_delay amount of time if they |
| 1013 | * are not manually dealt with first. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | */ |
| 1015 | void key_revoke(struct key *key) |
| 1016 | { |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 1017 | struct timespec now; |
| 1018 | time_t time; |
| 1019 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1020 | key_check(key); |
| 1021 | |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 1022 | /* make sure no one's trying to change or use the key when we mark it |
| 1023 | * - we tell lockdep that we might nest because we might be revoking an |
| 1024 | * authorisation key whilst holding the sem on a key we've just |
| 1025 | * instantiated |
| 1026 | */ |
| 1027 | down_write_nested(&key->sem, 1); |
| 1028 | if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) && |
| 1029 | key->type->revoke) |
David Howells | 04c567d | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 1030 | key->type->revoke(key); |
| 1031 | |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 1032 | /* set the death time to no more than the expiry time */ |
| 1033 | now = current_kernel_time(); |
| 1034 | time = now.tv_sec; |
| 1035 | if (key->revoked_at == 0 || key->revoked_at > time) { |
| 1036 | key->revoked_at = time; |
David Howells | c08ef80 | 2009-09-14 17:26:13 +0100 | [diff] [blame] | 1037 | key_schedule_gc(key->revoked_at + key_gc_delay); |
David Howells | 5d13544 | 2009-09-02 09:14:00 +0100 | [diff] [blame] | 1038 | } |
| 1039 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1040 | up_write(&key->sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1041 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1042 | EXPORT_SYMBOL(key_revoke); |
| 1043 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1044 | /** |
David Howells | fd75815 | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1045 | * key_invalidate - Invalidate a key. |
| 1046 | * @key: The key to be invalidated. |
| 1047 | * |
| 1048 | * Mark a key as being invalidated and have it cleaned up immediately. The key |
| 1049 | * is ignored by all searches and other operations from this point. |
| 1050 | */ |
| 1051 | void key_invalidate(struct key *key) |
| 1052 | { |
| 1053 | kenter("%d", key_serial(key)); |
| 1054 | |
| 1055 | key_check(key); |
| 1056 | |
| 1057 | if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) { |
| 1058 | down_write_nested(&key->sem, 1); |
| 1059 | if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) |
| 1060 | key_schedule_gc_links(); |
| 1061 | up_write(&key->sem); |
| 1062 | } |
| 1063 | } |
| 1064 | EXPORT_SYMBOL(key_invalidate); |
| 1065 | |
| 1066 | /** |
David Howells | 6a09d17 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1067 | * generic_key_instantiate - Simple instantiation of a key from preparsed data |
| 1068 | * @key: The key to be instantiated |
| 1069 | * @prep: The preparsed data to load. |
| 1070 | * |
| 1071 | * Instantiate a key from preparsed data. We assume we can just copy the data |
| 1072 | * in directly and clear the old pointers. |
| 1073 | * |
| 1074 | * This can be pointed to directly by the key type instantiate op pointer. |
| 1075 | */ |
| 1076 | int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep) |
| 1077 | { |
| 1078 | int ret; |
| 1079 | |
| 1080 | pr_devel("==>%s()\n", __func__); |
| 1081 | |
| 1082 | ret = key_payload_reserve(key, prep->quotalen); |
| 1083 | if (ret == 0) { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 1084 | rcu_assign_keypointer(key, prep->payload.data[0]); |
| 1085 | key->payload.data[1] = prep->payload.data[1]; |
| 1086 | key->payload.data[2] = prep->payload.data[2]; |
| 1087 | key->payload.data[3] = prep->payload.data[3]; |
| 1088 | prep->payload.data[0] = NULL; |
| 1089 | prep->payload.data[1] = NULL; |
| 1090 | prep->payload.data[2] = NULL; |
| 1091 | prep->payload.data[3] = NULL; |
David Howells | 6a09d17 | 2014-07-18 18:56:34 +0100 | [diff] [blame] | 1092 | } |
| 1093 | pr_devel("<==%s() = %d\n", __func__, ret); |
| 1094 | return ret; |
| 1095 | } |
| 1096 | EXPORT_SYMBOL(generic_key_instantiate); |
| 1097 | |
| 1098 | /** |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1099 | * register_key_type - Register a type of key. |
| 1100 | * @ktype: The new key type. |
| 1101 | * |
| 1102 | * Register a new key type. |
| 1103 | * |
| 1104 | * 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] | 1105 | */ |
| 1106 | int register_key_type(struct key_type *ktype) |
| 1107 | { |
| 1108 | struct key_type *p; |
| 1109 | int ret; |
| 1110 | |
David Howells | 7845bc39 | 2011-11-16 11:15:54 +0000 | [diff] [blame] | 1111 | memset(&ktype->lock_class, 0, sizeof(ktype->lock_class)); |
| 1112 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1113 | ret = -EEXIST; |
| 1114 | down_write(&key_types_sem); |
| 1115 | |
| 1116 | /* disallow key types with the same name */ |
| 1117 | list_for_each_entry(p, &key_types_list, link) { |
| 1118 | if (strcmp(p->name, ktype->name) == 0) |
| 1119 | goto out; |
| 1120 | } |
| 1121 | |
| 1122 | /* store the type */ |
| 1123 | list_add(&ktype->link, &key_types_list); |
David Howells | 1eb1bcf | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1124 | |
| 1125 | pr_notice("Key type %s registered\n", ktype->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1126 | ret = 0; |
| 1127 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1128 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1129 | up_write(&key_types_sem); |
| 1130 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1131 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1132 | EXPORT_SYMBOL(register_key_type); |
| 1133 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1134 | /** |
| 1135 | * unregister_key_type - Unregister a type of key. |
| 1136 | * @ktype: The key type. |
| 1137 | * |
| 1138 | * Unregister a key type and mark all the extant keys of this type as dead. |
| 1139 | * Those keys of this type are then destroyed to get rid of their payloads and |
| 1140 | * they and their links will be garbage collected as soon as possible. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1141 | */ |
| 1142 | void unregister_key_type(struct key_type *ktype) |
| 1143 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1144 | down_write(&key_types_sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1145 | list_del_init(&ktype->link); |
David Howells | 0c061b5 | 2011-08-22 14:09:36 +0100 | [diff] [blame] | 1146 | downgrade_write(&key_types_sem); |
| 1147 | key_gc_keytype(ktype); |
David Howells | 1eb1bcf | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 1148 | pr_notice("Key type %s unregistered\n", ktype->name); |
David Howells | 0c061b5 | 2011-08-22 14:09:36 +0100 | [diff] [blame] | 1149 | up_read(&key_types_sem); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1150 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1151 | EXPORT_SYMBOL(unregister_key_type); |
| 1152 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1153 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 1154 | * Initialise the key management state. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1155 | */ |
| 1156 | void __init key_init(void) |
| 1157 | { |
| 1158 | /* allocate a slab in which we can store keys */ |
| 1159 | key_jar = kmem_cache_create("key_jar", sizeof(struct key), |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 1160 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1161 | |
| 1162 | /* add the special key types */ |
| 1163 | list_add_tail(&key_type_keyring.link, &key_types_list); |
| 1164 | list_add_tail(&key_type_dead.link, &key_types_list); |
| 1165 | list_add_tail(&key_type_user.link, &key_types_list); |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 1166 | list_add_tail(&key_type_logon.link, &key_types_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1167 | |
| 1168 | /* record the root user tracking */ |
| 1169 | rb_link_node(&root_key_user.node, |
| 1170 | NULL, |
| 1171 | &key_user_tree.rb_node); |
| 1172 | |
| 1173 | rb_insert_color(&root_key_user.node, |
| 1174 | &key_user_tree); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 1175 | } |