46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-only
|
||
|
|
/*
|
||
|
|
* purgatory: Runs between two kernels
|
||
|
|
*
|
||
|
|
* Copyright (C) 2022 Huawei Technologies Co, Ltd.
|
||
|
|
*
|
||
|
|
* Author: Li Zhengyu (lizhengyu3@huawei.com)
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/purgatory.h>
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <linux/string.h>
|
||
|
|
#include <asm/string.h>
|
||
|
|
|
||
|
|
u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(".kexec-purgatory");
|
||
|
|
|
||
|
|
struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(".kexec-purgatory");
|
||
|
|
|
||
|
|
static int verify_sha256_digest(void)
|
||
|
|
{
|
||
|
|
struct kexec_sha_region *ptr, *end;
|
||
|
|
struct sha256_state ss;
|
||
|
|
u8 digest[SHA256_DIGEST_SIZE];
|
||
|
|
|
||
|
|
sha256_init(&ss);
|
||
|
|
end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
|
||
|
|
for (ptr = purgatory_sha_regions; ptr < end; ptr++)
|
||
|
|
sha256_update(&ss, (uint8_t *)(ptr->start), ptr->len);
|
||
|
|
sha256_final(&ss, digest);
|
||
|
|
if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)) != 0)
|
||
|
|
return 1;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* workaround for a warning with -Wmissing-prototypes */
|
||
|
|
void purgatory(void);
|
||
|
|
|
||
|
|
void purgatory(void)
|
||
|
|
{
|
||
|
|
if (verify_sha256_digest())
|
||
|
|
for (;;)
|
||
|
|
/* loop forever */
|
||
|
|
;
|
||
|
|
}
|