mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 08:44:21 +08:00
631cc66eb9
Include a PGP keyring containing the public keys required to perform module verification in the kernel image during build and create a special keyring during boot which is then populated with keys of crypto type holding the public keys found in the PGP keyring. These can be seen by root: [root@andromeda ~]# cat /proc/keys 07ad4ee0 I----- 1 perm 3f010000 0 0 crypto modsign.0: RSA 87b9b3bd [] 15c7f8c3 I----- 1 perm 1f030000 0 0 keyring .module_sign: 1/4 ... It is probably worth permitting root to invalidate these keys, resulting in their removal and preventing further modules from being loaded with that key. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
114 lines
2.9 KiB
C
114 lines
2.9 KiB
C
/* Public keys for module signature verification
|
|
*
|
|
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/cred.h>
|
|
#include <linux/err.h>
|
|
#include <keys/asymmetric-type.h>
|
|
#include "module-internal.h"
|
|
|
|
struct key *modsign_keyring;
|
|
|
|
extern __initdata const u8 modsign_certificate_list[];
|
|
extern __initdata const u8 modsign_certificate_list_end[];
|
|
asm(".section .init.data,\"aw\"\n"
|
|
"modsign_certificate_list:\n"
|
|
".incbin \"signing_key.x509\"\n"
|
|
".incbin \"extra_certificates\"\n"
|
|
"modsign_certificate_list_end:"
|
|
);
|
|
|
|
/*
|
|
* We need to make sure ccache doesn't cache the .o file as it doesn't notice
|
|
* if modsign.pub changes.
|
|
*/
|
|
static __initdata const char annoy_ccache[] = __TIME__ "foo";
|
|
|
|
/*
|
|
* Load the compiled-in keys
|
|
*/
|
|
static __init int module_verify_init(void)
|
|
{
|
|
pr_notice("Initialise module verification\n");
|
|
|
|
modsign_keyring = key_alloc(&key_type_keyring, ".module_sign",
|
|
KUIDT_INIT(0), KGIDT_INIT(0),
|
|
current_cred(),
|
|
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
KEY_USR_VIEW | KEY_USR_READ,
|
|
KEY_ALLOC_NOT_IN_QUOTA);
|
|
if (IS_ERR(modsign_keyring))
|
|
panic("Can't allocate module signing keyring\n");
|
|
|
|
if (key_instantiate_and_link(modsign_keyring, NULL, 0, NULL, NULL) < 0)
|
|
panic("Can't instantiate module signing keyring\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Must be initialised before we try and load the keys into the keyring.
|
|
*/
|
|
device_initcall(module_verify_init);
|
|
|
|
/*
|
|
* Load the compiled-in keys
|
|
*/
|
|
static __init int load_module_signing_keys(void)
|
|
{
|
|
key_ref_t key;
|
|
const u8 *p, *end;
|
|
size_t plen;
|
|
|
|
pr_notice("Loading module verification certificates\n");
|
|
|
|
end = modsign_certificate_list_end;
|
|
p = modsign_certificate_list;
|
|
while (p < end) {
|
|
/* Each cert begins with an ASN.1 SEQUENCE tag and must be more
|
|
* than 256 bytes in size.
|
|
*/
|
|
if (end - p < 4)
|
|
goto dodgy_cert;
|
|
if (p[0] != 0x30 &&
|
|
p[1] != 0x82)
|
|
goto dodgy_cert;
|
|
plen = (p[2] << 8) | p[3];
|
|
plen += 4;
|
|
if (plen > end - p)
|
|
goto dodgy_cert;
|
|
|
|
key = key_create_or_update(make_key_ref(modsign_keyring, 1),
|
|
"asymmetric",
|
|
NULL,
|
|
p,
|
|
plen,
|
|
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
KEY_USR_VIEW,
|
|
KEY_ALLOC_NOT_IN_QUOTA);
|
|
if (IS_ERR(key))
|
|
pr_err("MODSIGN: Problem loading in-kernel X.509 certificate (%ld)\n",
|
|
PTR_ERR(key));
|
|
else
|
|
pr_notice("MODSIGN: Loaded cert '%s'\n",
|
|
key_ref_to_ptr(key)->description);
|
|
p += plen;
|
|
}
|
|
|
|
return 0;
|
|
|
|
dodgy_cert:
|
|
pr_err("MODSIGN: Problem parsing in-kernel X.509 certificate list\n");
|
|
return 0;
|
|
}
|
|
late_initcall(load_module_signing_keys);
|