mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-29 05:55:02 +08:00
d1f044103d
Add a new Kconfig option called SYSTEM_REVOCATION_KEYS. If set, this option should be the filename of a PEM-formated file containing X.509 certificates to be included in the default blacklist keyring. DH Changes: - Make the new Kconfig option depend on SYSTEM_REVOCATION_LIST. - Fix SYSTEM_REVOCATION_KEYS=n, but CONFIG_SYSTEM_REVOCATION_LIST=y[1][2]. - Use CONFIG_SYSTEM_REVOCATION_LIST for extract-cert[3]. - Use CONFIG_SYSTEM_REVOCATION_LIST for revocation_certificates.o[3]. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: David Howells <dhowells@redhat.com> cc: Randy Dunlap <rdunlap@infradead.org> cc: keyrings@vger.kernel.org Link: https://lore.kernel.org/r/e1c15c74-82ce-3a69-44de-a33af9b320ea@infradead.org/ [1] Link: https://lore.kernel.org/r/20210303034418.106762-1-eric.snowberg@oracle.com/ [2] Link: https://lore.kernel.org/r/20210304175030.184131-1-eric.snowberg@oracle.com/ [3] Link: https://lore.kernel.org/r/20200930201508.35113-3-eric.snowberg@oracle.com/ Link: https://lore.kernel.org/r/20210122181054.32635-4-eric.snowberg@oracle.com/ # v5 Link: https://lore.kernel.org/r/161428673564.677100.4112098280028451629.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/161433312452.902181.4146169951896577982.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161529606657.163428.3340689182456495390.stgit@warthog.procyon.org.uk/ # v3
244 lines
5.7 KiB
C
244 lines
5.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/* System hash blacklist.
|
|
*
|
|
* Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "blacklist: "fmt
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/key.h>
|
|
#include <linux/key-type.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/ctype.h>
|
|
#include <linux/err.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/uidgid.h>
|
|
#include <keys/system_keyring.h>
|
|
#include "blacklist.h"
|
|
#include "common.h"
|
|
|
|
static struct key *blacklist_keyring;
|
|
|
|
#ifdef CONFIG_SYSTEM_REVOCATION_LIST
|
|
extern __initconst const u8 revocation_certificate_list[];
|
|
extern __initconst const unsigned long revocation_certificate_list_size;
|
|
#endif
|
|
|
|
/*
|
|
* The description must be a type prefix, a colon and then an even number of
|
|
* hex digits. The hash is kept in the description.
|
|
*/
|
|
static int blacklist_vet_description(const char *desc)
|
|
{
|
|
int n = 0;
|
|
|
|
if (*desc == ':')
|
|
return -EINVAL;
|
|
for (; *desc; desc++)
|
|
if (*desc == ':')
|
|
goto found_colon;
|
|
return -EINVAL;
|
|
|
|
found_colon:
|
|
desc++;
|
|
for (; *desc; desc++) {
|
|
if (!isxdigit(*desc) || isupper(*desc))
|
|
return -EINVAL;
|
|
n++;
|
|
}
|
|
|
|
if (n == 0 || n & 1)
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* The hash to be blacklisted is expected to be in the description. There will
|
|
* be no payload.
|
|
*/
|
|
static int blacklist_preparse(struct key_preparsed_payload *prep)
|
|
{
|
|
if (prep->datalen > 0)
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
static void blacklist_free_preparse(struct key_preparsed_payload *prep)
|
|
{
|
|
}
|
|
|
|
static void blacklist_describe(const struct key *key, struct seq_file *m)
|
|
{
|
|
seq_puts(m, key->description);
|
|
}
|
|
|
|
static struct key_type key_type_blacklist = {
|
|
.name = "blacklist",
|
|
.vet_description = blacklist_vet_description,
|
|
.preparse = blacklist_preparse,
|
|
.free_preparse = blacklist_free_preparse,
|
|
.instantiate = generic_key_instantiate,
|
|
.describe = blacklist_describe,
|
|
};
|
|
|
|
/**
|
|
* mark_hash_blacklisted - Add a hash to the system blacklist
|
|
* @hash: The hash as a hex string with a type prefix (eg. "tbs:23aa429783")
|
|
*/
|
|
int mark_hash_blacklisted(const char *hash)
|
|
{
|
|
key_ref_t key;
|
|
|
|
key = key_create_or_update(make_key_ref(blacklist_keyring, true),
|
|
"blacklist",
|
|
hash,
|
|
NULL,
|
|
0,
|
|
((KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
KEY_USR_VIEW),
|
|
KEY_ALLOC_NOT_IN_QUOTA |
|
|
KEY_ALLOC_BUILT_IN);
|
|
if (IS_ERR(key)) {
|
|
pr_err("Problem blacklisting hash (%ld)\n", PTR_ERR(key));
|
|
return PTR_ERR(key);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* is_hash_blacklisted - Determine if a hash is blacklisted
|
|
* @hash: The hash to be checked as a binary blob
|
|
* @hash_len: The length of the binary hash
|
|
* @type: Type of hash
|
|
*/
|
|
int is_hash_blacklisted(const u8 *hash, size_t hash_len, const char *type)
|
|
{
|
|
key_ref_t kref;
|
|
size_t type_len = strlen(type);
|
|
char *buffer, *p;
|
|
int ret = 0;
|
|
|
|
buffer = kmalloc(type_len + 1 + hash_len * 2 + 1, GFP_KERNEL);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
p = memcpy(buffer, type, type_len);
|
|
p += type_len;
|
|
*p++ = ':';
|
|
bin2hex(p, hash, hash_len);
|
|
p += hash_len * 2;
|
|
*p = 0;
|
|
|
|
kref = keyring_search(make_key_ref(blacklist_keyring, true),
|
|
&key_type_blacklist, buffer, false);
|
|
if (!IS_ERR(kref)) {
|
|
key_ref_put(kref);
|
|
ret = -EKEYREJECTED;
|
|
}
|
|
|
|
kfree(buffer);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(is_hash_blacklisted);
|
|
|
|
int is_binary_blacklisted(const u8 *hash, size_t hash_len)
|
|
{
|
|
if (is_hash_blacklisted(hash, hash_len, "bin") == -EKEYREJECTED)
|
|
return -EPERM;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(is_binary_blacklisted);
|
|
|
|
#ifdef CONFIG_SYSTEM_REVOCATION_LIST
|
|
/**
|
|
* add_key_to_revocation_list - Add a revocation certificate to the blacklist
|
|
* @data: The data blob containing the certificate
|
|
* @size: The size of data blob
|
|
*/
|
|
int add_key_to_revocation_list(const char *data, size_t size)
|
|
{
|
|
key_ref_t key;
|
|
|
|
key = key_create_or_update(make_key_ref(blacklist_keyring, true),
|
|
"asymmetric",
|
|
NULL,
|
|
data,
|
|
size,
|
|
((KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW),
|
|
KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_BUILT_IN);
|
|
|
|
if (IS_ERR(key)) {
|
|
pr_err("Problem with revocation key (%ld)\n", PTR_ERR(key));
|
|
return PTR_ERR(key);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* is_key_on_revocation_list - Determine if the key for a PKCS#7 message is revoked
|
|
* @pkcs7: The PKCS#7 message to check
|
|
*/
|
|
int is_key_on_revocation_list(struct pkcs7_message *pkcs7)
|
|
{
|
|
int ret;
|
|
|
|
ret = pkcs7_validate_trust(pkcs7, blacklist_keyring);
|
|
|
|
if (ret == 0)
|
|
return -EKEYREJECTED;
|
|
|
|
return -ENOKEY;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Initialise the blacklist
|
|
*/
|
|
static int __init blacklist_init(void)
|
|
{
|
|
const char *const *bl;
|
|
|
|
if (register_key_type(&key_type_blacklist) < 0)
|
|
panic("Can't allocate system blacklist key type\n");
|
|
|
|
blacklist_keyring =
|
|
keyring_alloc(".blacklist",
|
|
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(),
|
|
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
KEY_USR_VIEW | KEY_USR_READ |
|
|
KEY_USR_SEARCH,
|
|
KEY_ALLOC_NOT_IN_QUOTA |
|
|
KEY_ALLOC_SET_KEEP,
|
|
NULL, NULL);
|
|
if (IS_ERR(blacklist_keyring))
|
|
panic("Can't allocate system blacklist keyring\n");
|
|
|
|
for (bl = blacklist_hashes; *bl; bl++)
|
|
if (mark_hash_blacklisted(*bl) < 0)
|
|
pr_err("- blacklisting failed\n");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Must be initialised before we try and load the keys into the keyring.
|
|
*/
|
|
device_initcall(blacklist_init);
|
|
|
|
#ifdef CONFIG_SYSTEM_REVOCATION_LIST
|
|
/*
|
|
* Load the compiled-in list of revocation X.509 certificates.
|
|
*/
|
|
static __init int load_revocation_certificate_list(void)
|
|
{
|
|
if (revocation_certificate_list_size)
|
|
pr_notice("Loading compiled-in revocation X.509 certificates\n");
|
|
|
|
return load_certificate_list(revocation_certificate_list, revocation_certificate_list_size,
|
|
blacklist_keyring);
|
|
}
|
|
late_initcall(load_revocation_certificate_list);
|
|
#endif
|