linux-sg2042/arch/s390/purgatory/purgatory.c

34 lines
734 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Purgatory code running between two kernels.
*
* Copyright IBM Corp. 2018
*
* Author(s): Philipp Rudo <prudo@linux.vnet.ibm.com>
*/
#include <linux/kexec.h>
#include <linux/sha256.h>
#include <linux/string.h>
#include <asm/purgatory.h>
int verify_sha256_digest(void)
{
struct kexec_sha_region *ptr, *end;
u8 digest[SHA256_DIGEST_SIZE];
struct sha256_state sctx;
sha256_init(&sctx);
end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
for (ptr = purgatory_sha_regions; ptr < end; ptr++)
sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
sha256_final(&sctx, digest);
if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)))
return 1;
return 0;
}