/* 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);
