Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* user_defined.c: user defined key type |
| 2 | * |
| 3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/slab.h> |
| 15 | #include <linux/seq_file.h> |
| 16 | #include <linux/err.h> |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 17 | #include <keys/user-type.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <asm/uaccess.h> |
| 19 | #include "internal.h" |
| 20 | |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 21 | static int logon_vet_description(const char *desc); |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | /* |
| 24 | * user defined keys take an arbitrary string as the description and an |
| 25 | * arbitrary blob of data as the payload |
| 26 | */ |
| 27 | struct key_type key_type_user = { |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 28 | .name = "user", |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 29 | .preparse = user_preparse, |
| 30 | .free_preparse = user_free_preparse, |
| 31 | .instantiate = generic_key_instantiate, |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 32 | .update = user_update, |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 33 | .revoke = user_revoke, |
| 34 | .destroy = user_destroy, |
| 35 | .describe = user_describe, |
| 36 | .read = user_read, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | }; |
| 38 | |
Michael Halcrow | 16c29b6 | 2005-06-23 22:00:58 -0700 | [diff] [blame] | 39 | EXPORT_SYMBOL_GPL(key_type_user); |
| 40 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | /* |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 42 | * This key type is essentially the same as key_type_user, but it does |
| 43 | * not define a .read op. This is suitable for storing username and |
| 44 | * password pairs in the keyring that you do not want to be readable |
| 45 | * from userspace. |
| 46 | */ |
| 47 | struct key_type key_type_logon = { |
| 48 | .name = "logon", |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 49 | .preparse = user_preparse, |
| 50 | .free_preparse = user_free_preparse, |
| 51 | .instantiate = generic_key_instantiate, |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 52 | .update = user_update, |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 53 | .revoke = user_revoke, |
| 54 | .destroy = user_destroy, |
| 55 | .describe = user_describe, |
| 56 | .vet_description = logon_vet_description, |
| 57 | }; |
| 58 | EXPORT_SYMBOL_GPL(key_type_logon); |
| 59 | |
| 60 | /* |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 61 | * Preparse a user defined key payload |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | */ |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 63 | int user_preparse(struct key_preparsed_payload *prep) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | { |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 65 | struct user_key_payload *upayload; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 66 | size_t datalen = prep->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 68 | if (datalen <= 0 || datalen > 32767 || !prep->data) |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 69 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 71 | upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL); |
| 72 | if (!upayload) |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 73 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 75 | /* attach the data */ |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 76 | prep->quotalen = datalen; |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 77 | prep->payload.data[0] = upayload; |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 78 | upayload->datalen = datalen; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 79 | memcpy(upayload->data, prep->data, datalen); |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 80 | return 0; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 81 | } |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 82 | EXPORT_SYMBOL_GPL(user_preparse); |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 83 | |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 84 | /* |
| 85 | * Free a preparse of a user defined key payload |
| 86 | */ |
| 87 | void user_free_preparse(struct key_preparsed_payload *prep) |
| 88 | { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 89 | kfree(prep->payload.data[0]); |
David Howells | f916778 | 2014-07-18 18:56:35 +0100 | [diff] [blame] | 90 | } |
| 91 | EXPORT_SYMBOL_GPL(user_free_preparse); |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 92 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | * update a user defined key |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 95 | * - the key's semaphore is write-locked |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | */ |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 97 | int user_update(struct key *key, struct key_preparsed_payload *prep) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | { |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 99 | struct user_key_payload *upayload, *zap; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 100 | size_t datalen = prep->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | int ret; |
| 102 | |
| 103 | ret = -EINVAL; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 104 | if (datalen <= 0 || datalen > 32767 || !prep->data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | goto error; |
| 106 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 107 | /* construct a replacement payload */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | ret = -ENOMEM; |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 109 | upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL); |
| 110 | if (!upayload) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | goto error; |
| 112 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 113 | upayload->datalen = datalen; |
David Howells | cf7f601 | 2012-09-13 13:06:29 +0100 | [diff] [blame] | 114 | memcpy(upayload->data, prep->data, datalen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | |
| 116 | /* check the quota and attach the new data */ |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 117 | zap = upayload; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | |
| 119 | ret = key_payload_reserve(key, datalen); |
| 120 | |
| 121 | if (ret == 0) { |
| 122 | /* attach the new data, displacing the old */ |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 123 | zap = key->payload.data[0]; |
Mimi Zohar | f6b2457 | 2012-01-18 10:03:14 +0000 | [diff] [blame] | 124 | rcu_assign_keypointer(key, upayload); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | key->expiry = 0; |
| 126 | } |
| 127 | |
David Howells | 9f35a33 | 2011-11-15 22:09:45 +0000 | [diff] [blame] | 128 | if (zap) |
| 129 | kfree_rcu(zap, rcu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 131 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 133 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 135 | EXPORT_SYMBOL_GPL(user_update); |
| 136 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | /* |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 138 | * dispose of the links from a revoked keyring |
| 139 | * - called with the key sem write-locked |
| 140 | */ |
| 141 | void user_revoke(struct key *key) |
| 142 | { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 143 | struct user_key_payload *upayload = key->payload.data[0]; |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 144 | |
| 145 | /* clear the quota */ |
| 146 | key_payload_reserve(key, 0); |
| 147 | |
| 148 | if (upayload) { |
Mimi Zohar | f6b2457 | 2012-01-18 10:03:14 +0000 | [diff] [blame] | 149 | rcu_assign_keypointer(key, NULL); |
Lai Jiangshan | 3acb458 | 2011-03-18 12:11:07 +0800 | [diff] [blame] | 150 | kfree_rcu(upayload, rcu); |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 151 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 152 | } |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 153 | |
| 154 | EXPORT_SYMBOL(user_revoke); |
| 155 | |
David Howells | 31204ed | 2006-06-26 00:24:51 -0700 | [diff] [blame] | 156 | /* |
| 157 | * dispose of the data dangling from the corpse of a user key |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | */ |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 159 | void user_destroy(struct key *key) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 161 | struct user_key_payload *upayload = key->payload.data[0]; |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 162 | |
| 163 | kfree(upayload); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 164 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 166 | EXPORT_SYMBOL_GPL(user_destroy); |
| 167 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | /* |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 169 | * describe the user key |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | */ |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 171 | void user_describe(const struct key *key, struct seq_file *m) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | { |
| 173 | seq_puts(m, key->description); |
David Howells | 78b7280 | 2011-03-11 17:57:23 +0000 | [diff] [blame] | 174 | if (key_is_instantiated(key)) |
| 175 | seq_printf(m, ": %u", key->datalen); |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 176 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 178 | EXPORT_SYMBOL_GPL(user_describe); |
| 179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | /* |
| 181 | * read the key data |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 182 | * - the key's semaphore is read-locked |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | */ |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 184 | long user_read(const struct key *key, char __user *buffer, size_t buflen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 186 | const struct user_key_payload *upayload; |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 187 | long ret; |
| 188 | |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 189 | upayload = user_key_payload(key); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 190 | ret = upayload->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | |
| 192 | /* we can return the data as is */ |
| 193 | if (buffer && buflen > 0) { |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 194 | if (buflen > upayload->datalen) |
| 195 | buflen = upayload->datalen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 197 | if (copy_to_user(buffer, upayload->data, buflen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | ret = -EFAULT; |
| 199 | } |
| 200 | |
| 201 | return ret; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 202 | } |
David Howells | 2aa349f | 2005-10-30 15:02:42 -0800 | [diff] [blame] | 203 | |
| 204 | EXPORT_SYMBOL_GPL(user_read); |
Jeff Layton | 9f6ed2c | 2012-01-17 16:09:11 -0500 | [diff] [blame] | 205 | |
| 206 | /* Vet the description for a "logon" key */ |
| 207 | static int logon_vet_description(const char *desc) |
| 208 | { |
| 209 | char *p; |
| 210 | |
| 211 | /* require a "qualified" description string */ |
| 212 | p = strchr(desc, ':'); |
| 213 | if (!p) |
| 214 | return -EINVAL; |
| 215 | |
| 216 | /* also reject description with ':' as first char */ |
| 217 | if (p == desc) |
| 218 | return -EINVAL; |
| 219 | |
| 220 | return 0; |
| 221 | } |