Thomas Gleixner | b4d0d23 | 2019-05-20 19:08:01 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 2 | /* System trusted keyring for trusted public keys |
| 3 | * |
| 4 | * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. |
| 5 | * Written by David Howells (dhowells@redhat.com) |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <linux/export.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/sched.h> |
| 11 | #include <linux/cred.h> |
| 12 | #include <linux/err.h> |
Mat Martineau | 2b6aa41 | 2016-08-31 16:05:43 -0700 | [diff] [blame] | 13 | #include <linux/slab.h> |
Mickaël Salaün | a6cb0ab | 2020-11-20 19:04:25 +0100 | [diff] [blame] | 14 | #include <linux/uidgid.h> |
Yannik Sembritzki | 817aef2 | 2018-08-16 14:05:10 +0100 | [diff] [blame] | 15 | #include <linux/verification.h> |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 16 | #include <keys/asymmetric-type.h> |
| 17 | #include <keys/system_keyring.h> |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 18 | #include <crypto/pkcs7.h> |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 19 | |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 20 | static struct key *builtin_trusted_keys; |
| 21 | #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING |
| 22 | static struct key *secondary_trusted_keys; |
| 23 | #endif |
Eric Snowberg | 56edb6c | 2022-01-25 21:58:30 -0500 | [diff] [blame] | 24 | #ifdef CONFIG_INTEGRITY_MACHINE_KEYRING |
| 25 | static struct key *machine_trusted_keys; |
| 26 | #endif |
Kairui Song | 219a3e8 | 2019-01-21 17:59:28 +0800 | [diff] [blame] | 27 | #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING |
| 28 | static struct key *platform_trusted_keys; |
| 29 | #endif |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 30 | |
| 31 | extern __initconst const u8 system_certificate_list[]; |
Hendrik Brueckner | 6222698 | 2013-12-05 14:48:22 +0100 | [diff] [blame] | 32 | extern __initconst const unsigned long system_certificate_list_size; |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 33 | extern __initconst const unsigned long module_cert_size; |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 34 | |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 35 | /** |
Eric Snowberg | ef97e774 | 2023-03-02 11:46:48 -0500 | [diff] [blame] | 36 | * restrict_link_by_builtin_trusted - Restrict keyring addition by built-in CA |
| 37 | * @dest_keyring: Keyring being linked to. |
| 38 | * @type: The type of key being added. |
| 39 | * @payload: The payload of the new key. |
| 40 | * @restriction_key: A ring of keys that can be used to vouch for the new cert. |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 41 | * |
| 42 | * Restrict the addition of keys into a keyring based on the key-to-be-added |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 43 | * being vouched for by a key in the built in system keyring. |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 44 | */ |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 45 | int restrict_link_by_builtin_trusted(struct key *dest_keyring, |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 46 | const struct key_type *type, |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 47 | const union key_payload *payload, |
| 48 | struct key *restriction_key) |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 49 | { |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 50 | return restrict_link_by_signature(dest_keyring, type, payload, |
| 51 | builtin_trusted_keys); |
David Howells | a511e1a | 2016-04-06 16:14:26 +0100 | [diff] [blame] | 52 | } |
| 53 | |
Eric Snowberg | 4cfb908 | 2023-05-22 19:09:42 -0400 | [diff] [blame] | 54 | /** |
| 55 | * restrict_link_by_digsig_builtin - Restrict digitalSignature key additions by the built-in keyring |
| 56 | * @dest_keyring: Keyring being linked to. |
| 57 | * @type: The type of key being added. |
| 58 | * @payload: The payload of the new key. |
| 59 | * @restriction_key: A ring of keys that can be used to vouch for the new cert. |
| 60 | * |
| 61 | * Restrict the addition of keys into a keyring based on the key-to-be-added |
| 62 | * being vouched for by a key in the built in system keyring. The new key |
| 63 | * must have the digitalSignature usage field set. |
| 64 | */ |
| 65 | int restrict_link_by_digsig_builtin(struct key *dest_keyring, |
| 66 | const struct key_type *type, |
| 67 | const union key_payload *payload, |
| 68 | struct key *restriction_key) |
| 69 | { |
| 70 | return restrict_link_by_digsig(dest_keyring, type, payload, |
| 71 | builtin_trusted_keys); |
| 72 | } |
| 73 | |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 74 | #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING |
| 75 | /** |
| 76 | * restrict_link_by_builtin_and_secondary_trusted - Restrict keyring |
Eric Snowberg | ef97e774 | 2023-03-02 11:46:48 -0500 | [diff] [blame] | 77 | * addition by both built-in and secondary keyrings. |
| 78 | * @dest_keyring: Keyring being linked to. |
| 79 | * @type: The type of key being added. |
| 80 | * @payload: The payload of the new key. |
| 81 | * @restrict_key: A ring of keys that can be used to vouch for the new cert. |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 82 | * |
| 83 | * Restrict the addition of keys into a keyring based on the key-to-be-added |
| 84 | * being vouched for by a key in either the built-in or the secondary system |
| 85 | * keyrings. |
| 86 | */ |
| 87 | int restrict_link_by_builtin_and_secondary_trusted( |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 88 | struct key *dest_keyring, |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 89 | const struct key_type *type, |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 90 | const union key_payload *payload, |
| 91 | struct key *restrict_key) |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 92 | { |
| 93 | /* If we have a secondary trusted keyring, then that contains a link |
| 94 | * through to the builtin keyring and the search will follow that link. |
| 95 | */ |
| 96 | if (type == &key_type_keyring && |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 97 | dest_keyring == secondary_trusted_keys && |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 98 | payload == &builtin_trusted_keys->payload) |
| 99 | /* Allow the builtin keyring to be added to the secondary */ |
| 100 | return 0; |
| 101 | |
Mat Martineau | aaf66c8 | 2016-08-30 11:33:13 -0700 | [diff] [blame] | 102 | return restrict_link_by_signature(dest_keyring, type, payload, |
| 103 | secondary_trusted_keys); |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 104 | } |
Mat Martineau | 2b6aa41 | 2016-08-31 16:05:43 -0700 | [diff] [blame] | 105 | |
Eric Snowberg | 4cfb908 | 2023-05-22 19:09:42 -0400 | [diff] [blame] | 106 | /** |
| 107 | * restrict_link_by_digsig_builtin_and_secondary - Restrict by digitalSignature. |
| 108 | * @dest_keyring: Keyring being linked to. |
| 109 | * @type: The type of key being added. |
| 110 | * @payload: The payload of the new key. |
| 111 | * @restrict_key: A ring of keys that can be used to vouch for the new cert. |
| 112 | * |
| 113 | * Restrict the addition of keys into a keyring based on the key-to-be-added |
| 114 | * being vouched for by a key in either the built-in or the secondary system |
| 115 | * keyrings. The new key must have the digitalSignature usage field set. |
| 116 | */ |
| 117 | int restrict_link_by_digsig_builtin_and_secondary(struct key *dest_keyring, |
| 118 | const struct key_type *type, |
| 119 | const union key_payload *payload, |
| 120 | struct key *restrict_key) |
| 121 | { |
| 122 | /* If we have a secondary trusted keyring, then that contains a link |
| 123 | * through to the builtin keyring and the search will follow that link. |
| 124 | */ |
| 125 | if (type == &key_type_keyring && |
| 126 | dest_keyring == secondary_trusted_keys && |
| 127 | payload == &builtin_trusted_keys->payload) |
| 128 | /* Allow the builtin keyring to be added to the secondary */ |
| 129 | return 0; |
| 130 | |
| 131 | return restrict_link_by_digsig(dest_keyring, type, payload, |
| 132 | secondary_trusted_keys); |
| 133 | } |
| 134 | |
Eric Snowberg | ef97e774 | 2023-03-02 11:46:48 -0500 | [diff] [blame] | 135 | /* |
Mat Martineau | 2b6aa41 | 2016-08-31 16:05:43 -0700 | [diff] [blame] | 136 | * Allocate a struct key_restriction for the "builtin and secondary trust" |
| 137 | * keyring. Only for use in system_trusted_keyring_init(). |
| 138 | */ |
| 139 | static __init struct key_restriction *get_builtin_and_secondary_restriction(void) |
| 140 | { |
| 141 | struct key_restriction *restriction; |
| 142 | |
| 143 | restriction = kzalloc(sizeof(struct key_restriction), GFP_KERNEL); |
| 144 | |
| 145 | if (!restriction) |
| 146 | panic("Can't allocate secondary trusted keyring restriction\n"); |
| 147 | |
Eric Snowberg | 087aa4e | 2022-01-25 21:58:31 -0500 | [diff] [blame] | 148 | if (IS_ENABLED(CONFIG_INTEGRITY_MACHINE_KEYRING)) |
| 149 | restriction->check = restrict_link_by_builtin_secondary_and_machine; |
| 150 | else |
| 151 | restriction->check = restrict_link_by_builtin_and_secondary_trusted; |
Mat Martineau | 2b6aa41 | 2016-08-31 16:05:43 -0700 | [diff] [blame] | 152 | |
| 153 | return restriction; |
| 154 | } |
Nayna Jain | 44e69ea | 2023-08-15 07:27:22 -0400 | [diff] [blame] | 155 | |
| 156 | /** |
| 157 | * add_to_secondary_keyring - Add to secondary keyring. |
| 158 | * @source: Source of key |
| 159 | * @data: The blob holding the key |
| 160 | * @len: The length of the data blob |
| 161 | * |
| 162 | * Add a key to the secondary keyring. The key must be vouched for by a key in the builtin, |
| 163 | * machine or secondary keyring itself. |
| 164 | */ |
| 165 | void __init add_to_secondary_keyring(const char *source, const void *data, size_t len) |
| 166 | { |
| 167 | key_ref_t key; |
| 168 | key_perm_t perm; |
| 169 | |
| 170 | perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW; |
| 171 | |
| 172 | key = key_create_or_update(make_key_ref(secondary_trusted_keys, 1), |
| 173 | "asymmetric", |
| 174 | NULL, data, len, perm, |
| 175 | KEY_ALLOC_NOT_IN_QUOTA); |
| 176 | if (IS_ERR(key)) { |
| 177 | pr_err("Problem loading X.509 certificate from %s to secondary keyring %ld\n", |
| 178 | source, PTR_ERR(key)); |
| 179 | return; |
| 180 | } |
| 181 | |
| 182 | pr_notice("Loaded X.509 cert '%s'\n", key_ref_to_ptr(key)->description); |
| 183 | key_ref_put(key); |
| 184 | } |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 185 | #endif |
Eric Snowberg | 56edb6c | 2022-01-25 21:58:30 -0500 | [diff] [blame] | 186 | #ifdef CONFIG_INTEGRITY_MACHINE_KEYRING |
| 187 | void __init set_machine_trusted_keys(struct key *keyring) |
| 188 | { |
| 189 | machine_trusted_keys = keyring; |
Eric Snowberg | 087aa4e | 2022-01-25 21:58:31 -0500 | [diff] [blame] | 190 | |
| 191 | if (key_link(secondary_trusted_keys, machine_trusted_keys) < 0) |
| 192 | panic("Can't link (machine) trusted keyrings\n"); |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * restrict_link_by_builtin_secondary_and_machine - Restrict keyring addition. |
| 197 | * @dest_keyring: Keyring being linked to. |
| 198 | * @type: The type of key being added. |
| 199 | * @payload: The payload of the new key. |
| 200 | * @restrict_key: A ring of keys that can be used to vouch for the new cert. |
| 201 | * |
| 202 | * Restrict the addition of keys into a keyring based on the key-to-be-added |
| 203 | * being vouched for by a key in either the built-in, the secondary, or |
| 204 | * the machine keyrings. |
| 205 | */ |
| 206 | int restrict_link_by_builtin_secondary_and_machine( |
| 207 | struct key *dest_keyring, |
| 208 | const struct key_type *type, |
| 209 | const union key_payload *payload, |
| 210 | struct key *restrict_key) |
| 211 | { |
| 212 | if (machine_trusted_keys && type == &key_type_keyring && |
| 213 | dest_keyring == secondary_trusted_keys && |
| 214 | payload == &machine_trusted_keys->payload) |
| 215 | /* Allow the machine keyring to be added to the secondary */ |
| 216 | return 0; |
| 217 | |
| 218 | return restrict_link_by_builtin_and_secondary_trusted(dest_keyring, type, |
| 219 | payload, restrict_key); |
Eric Snowberg | 56edb6c | 2022-01-25 21:58:30 -0500 | [diff] [blame] | 220 | } |
| 221 | #endif |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 222 | |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 223 | /* |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 224 | * Create the trusted keyrings |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 225 | */ |
| 226 | static __init int system_trusted_keyring_init(void) |
| 227 | { |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 228 | pr_notice("Initialise system trusted keyrings\n"); |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 229 | |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 230 | builtin_trusted_keys = |
| 231 | keyring_alloc(".builtin_trusted_keys", |
Mickaël Salaün | a6cb0ab | 2020-11-20 19:04:25 +0100 | [diff] [blame] | 232 | GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(), |
Linus Torvalds | 028db3e | 2019-07-10 18:43:43 -0700 | [diff] [blame] | 233 | ((KEY_POS_ALL & ~KEY_POS_SETATTR) | |
| 234 | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH), |
| 235 | KEY_ALLOC_NOT_IN_QUOTA, |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 236 | NULL, NULL); |
| 237 | if (IS_ERR(builtin_trusted_keys)) |
| 238 | panic("Can't allocate builtin trusted keyring\n"); |
| 239 | |
| 240 | #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING |
| 241 | secondary_trusted_keys = |
| 242 | keyring_alloc(".secondary_trusted_keys", |
Mickaël Salaün | a6cb0ab | 2020-11-20 19:04:25 +0100 | [diff] [blame] | 243 | GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(), |
Linus Torvalds | 028db3e | 2019-07-10 18:43:43 -0700 | [diff] [blame] | 244 | ((KEY_POS_ALL & ~KEY_POS_SETATTR) | |
| 245 | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH | |
| 246 | KEY_USR_WRITE), |
| 247 | KEY_ALLOC_NOT_IN_QUOTA, |
Mat Martineau | 2b6aa41 | 2016-08-31 16:05:43 -0700 | [diff] [blame] | 248 | get_builtin_and_secondary_restriction(), |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 249 | NULL); |
| 250 | if (IS_ERR(secondary_trusted_keys)) |
| 251 | panic("Can't allocate secondary trusted keyring\n"); |
| 252 | |
| 253 | if (key_link(secondary_trusted_keys, builtin_trusted_keys) < 0) |
| 254 | panic("Can't link trusted keyrings\n"); |
| 255 | #endif |
| 256 | |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 257 | return 0; |
| 258 | } |
| 259 | |
| 260 | /* |
| 261 | * Must be initialised before we try and load the keys into the keyring. |
| 262 | */ |
| 263 | device_initcall(system_trusted_keyring_init); |
| 264 | |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 265 | __init int load_module_cert(struct key *keyring) |
| 266 | { |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 267 | if (!IS_ENABLED(CONFIG_IMA_APPRAISE_MODSIG)) |
| 268 | return 0; |
| 269 | |
| 270 | pr_notice("Loading compiled-in module X.509 certificates\n"); |
| 271 | |
David Howells | 60050ff | 2022-05-18 23:48:09 +0100 | [diff] [blame] | 272 | return x509_load_certificate_list(system_certificate_list, |
| 273 | module_cert_size, keyring); |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 274 | } |
| 275 | |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 276 | /* |
| 277 | * Load the compiled-in list of X.509 certificates. |
| 278 | */ |
| 279 | static __init int load_system_certificate_list(void) |
| 280 | { |
Linus Torvalds | e6f0bf0 | 2021-05-01 15:32:18 -0700 | [diff] [blame] | 281 | const u8 *p; |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 282 | unsigned long size; |
| 283 | |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 284 | pr_notice("Loading compiled-in X.509 certificates\n"); |
| 285 | |
Nayna Jain | 6cbdfb3 | 2021-04-09 10:35:07 -0400 | [diff] [blame] | 286 | #ifdef CONFIG_MODULE_SIG |
| 287 | p = system_certificate_list; |
| 288 | size = system_certificate_list_size; |
| 289 | #else |
| 290 | p = system_certificate_list + module_cert_size; |
| 291 | size = system_certificate_list_size - module_cert_size; |
| 292 | #endif |
| 293 | |
David Howells | 60050ff | 2022-05-18 23:48:09 +0100 | [diff] [blame] | 294 | return x509_load_certificate_list(p, size, builtin_trusted_keys); |
David Howells | b56e5a1 | 2013-08-30 16:07:30 +0100 | [diff] [blame] | 295 | } |
| 296 | late_initcall(load_system_certificate_list); |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 297 | |
| 298 | #ifdef CONFIG_SYSTEM_DATA_VERIFICATION |
| 299 | |
| 300 | /** |
Thiago Jung Bauermann | 2a7bf67 | 2019-06-27 23:19:25 -0300 | [diff] [blame] | 301 | * verify_pkcs7_message_sig - Verify a PKCS#7-based signature on system data. |
David Howells | e68503b | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 302 | * @data: The data to be verified (NULL if expecting internal data). |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 303 | * @len: Size of @data. |
Thiago Jung Bauermann | 2a7bf67 | 2019-06-27 23:19:25 -0300 | [diff] [blame] | 304 | * @pkcs7: The PKCS#7 message that is the signature. |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 305 | * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, |
| 306 | * (void *)1UL for all trusted keys). |
David Howells | 99db443 | 2015-08-05 15:22:27 +0100 | [diff] [blame] | 307 | * @usage: The use to which the key is being put. |
David Howells | e68503b | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 308 | * @view_content: Callback to gain access to content. |
| 309 | * @ctx: Context for callback. |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 310 | */ |
Thiago Jung Bauermann | 2a7bf67 | 2019-06-27 23:19:25 -0300 | [diff] [blame] | 311 | int verify_pkcs7_message_sig(const void *data, size_t len, |
| 312 | struct pkcs7_message *pkcs7, |
| 313 | struct key *trusted_keys, |
| 314 | enum key_being_used_for usage, |
| 315 | int (*view_content)(void *ctx, |
| 316 | const void *data, size_t len, |
| 317 | size_t asn1hdrlen), |
| 318 | void *ctx) |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 319 | { |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 320 | int ret; |
| 321 | |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 322 | /* The data should be detached - so we need to supply it. */ |
David Howells | e68503b | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 323 | if (data && pkcs7_supply_detached_data(pkcs7, data, len) < 0) { |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 324 | pr_err("PKCS#7 signature with non-detached data\n"); |
| 325 | ret = -EBADMSG; |
| 326 | goto error; |
| 327 | } |
| 328 | |
David Howells | 99db443 | 2015-08-05 15:22:27 +0100 | [diff] [blame] | 329 | ret = pkcs7_verify(pkcs7, usage); |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 330 | if (ret < 0) |
| 331 | goto error; |
| 332 | |
Eric Snowberg | 218a268 | 2023-08-17 10:04:07 -0400 | [diff] [blame] | 333 | ret = is_key_on_revocation_list(pkcs7); |
| 334 | if (ret != -ENOKEY) { |
| 335 | pr_devel("PKCS#7 key is on revocation list\n"); |
| 336 | goto error; |
| 337 | } |
| 338 | |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 339 | if (!trusted_keys) { |
| 340 | trusted_keys = builtin_trusted_keys; |
Yannik Sembritzki | 817aef2 | 2018-08-16 14:05:10 +0100 | [diff] [blame] | 341 | } else if (trusted_keys == VERIFY_USE_SECONDARY_KEYRING) { |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 342 | #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING |
| 343 | trusted_keys = secondary_trusted_keys; |
| 344 | #else |
| 345 | trusted_keys = builtin_trusted_keys; |
| 346 | #endif |
Kairui Song | 278311e | 2019-01-21 17:59:29 +0800 | [diff] [blame] | 347 | } else if (trusted_keys == VERIFY_USE_PLATFORM_KEYRING) { |
| 348 | #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING |
| 349 | trusted_keys = platform_trusted_keys; |
| 350 | #else |
| 351 | trusted_keys = NULL; |
| 352 | #endif |
| 353 | if (!trusted_keys) { |
| 354 | ret = -ENOKEY; |
| 355 | pr_devel("PKCS#7 platform keyring is not available\n"); |
| 356 | goto error; |
| 357 | } |
David Howells | d3bfe84 | 2016-04-06 16:14:27 +0100 | [diff] [blame] | 358 | } |
David Howells | bda850c | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 359 | ret = pkcs7_validate_trust(pkcs7, trusted_keys); |
| 360 | if (ret < 0) { |
| 361 | if (ret == -ENOKEY) |
Kairui Song | 278311e | 2019-01-21 17:59:29 +0800 | [diff] [blame] | 362 | pr_devel("PKCS#7 signature not signed with a trusted key\n"); |
David Howells | e68503b | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 363 | goto error; |
| 364 | } |
| 365 | |
| 366 | if (view_content) { |
| 367 | size_t asn1hdrlen; |
| 368 | |
| 369 | ret = pkcs7_get_content_data(pkcs7, &data, &len, &asn1hdrlen); |
| 370 | if (ret < 0) { |
| 371 | if (ret == -ENODATA) |
| 372 | pr_devel("PKCS#7 message does not contain data\n"); |
| 373 | goto error; |
| 374 | } |
| 375 | |
| 376 | ret = view_content(ctx, data, len, asn1hdrlen); |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 377 | } |
| 378 | |
| 379 | error: |
Thiago Jung Bauermann | 2a7bf67 | 2019-06-27 23:19:25 -0300 | [diff] [blame] | 380 | pr_devel("<==%s() = %d\n", __func__, ret); |
| 381 | return ret; |
| 382 | } |
| 383 | |
| 384 | /** |
| 385 | * verify_pkcs7_signature - Verify a PKCS#7-based signature on system data. |
| 386 | * @data: The data to be verified (NULL if expecting internal data). |
| 387 | * @len: Size of @data. |
| 388 | * @raw_pkcs7: The PKCS#7 message that is the signature. |
| 389 | * @pkcs7_len: The size of @raw_pkcs7. |
| 390 | * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, |
| 391 | * (void *)1UL for all trusted keys). |
| 392 | * @usage: The use to which the key is being put. |
| 393 | * @view_content: Callback to gain access to content. |
| 394 | * @ctx: Context for callback. |
| 395 | */ |
| 396 | int verify_pkcs7_signature(const void *data, size_t len, |
| 397 | const void *raw_pkcs7, size_t pkcs7_len, |
| 398 | struct key *trusted_keys, |
| 399 | enum key_being_used_for usage, |
| 400 | int (*view_content)(void *ctx, |
| 401 | const void *data, size_t len, |
| 402 | size_t asn1hdrlen), |
| 403 | void *ctx) |
| 404 | { |
| 405 | struct pkcs7_message *pkcs7; |
| 406 | int ret; |
| 407 | |
| 408 | pkcs7 = pkcs7_parse_message(raw_pkcs7, pkcs7_len); |
| 409 | if (IS_ERR(pkcs7)) |
| 410 | return PTR_ERR(pkcs7); |
| 411 | |
| 412 | ret = verify_pkcs7_message_sig(data, len, pkcs7, trusted_keys, usage, |
| 413 | view_content, ctx); |
| 414 | |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 415 | pkcs7_free_message(pkcs7); |
| 416 | pr_devel("<==%s() = %d\n", __func__, ret); |
| 417 | return ret; |
| 418 | } |
David Howells | e68503b | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 419 | EXPORT_SYMBOL_GPL(verify_pkcs7_signature); |
David Howells | 091f6e2 | 2015-07-20 21:16:28 +0100 | [diff] [blame] | 420 | |
| 421 | #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ |
Kairui Song | 219a3e8 | 2019-01-21 17:59:28 +0800 | [diff] [blame] | 422 | |
| 423 | #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING |
| 424 | void __init set_platform_trusted_keys(struct key *keyring) |
| 425 | { |
| 426 | platform_trusted_keys = keyring; |
| 427 | } |
| 428 | #endif |