1 // SPDX-License-Identifier: GPL-2.0
3 * Purgatory code running between two kernels.
5 * Copyright IBM Corp. 2018
7 * Author(s): Philipp Rudo <prudo@linux.vnet.ibm.com>
10 #include <linux/kexec.h>
11 #include <linux/sha256.h>
12 #include <linux/string.h>
13 #include <asm/purgatory.h>
15 struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX];
16 u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE];
24 int verify_sha256_digest(void)
26 struct kexec_sha_region *ptr, *end;
27 u8 digest[SHA256_DIGEST_SIZE];
28 struct sha256_state sctx;
31 end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
33 for (ptr = purgatory_sha_regions; ptr < end; ptr++)
34 sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
36 sha256_final(&sctx, digest);
38 if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)))