kernel_samsung_a53x/drivers/crypto/fmp/fmp_fips_integrity.c
2024-06-15 16:02:09 -03:00

133 lines
3.4 KiB
C
Executable file

// SPDX-License-Identifier: GPL-2.0
/*
* Created in Samsung Ukraine R&D Center (SRK) under a contract between
* LLC "Samsung Electronics Ukraine Company" (Kyiv, Ukraine)
* and "Samsung Electronics Co", Ltd (Seoul, Republic of Korea)
* Copyright: (c) Samsung Electronics Co, Ltd 2020. All rights reserved.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <crypto/fmp.h>
#include <crypto/hmac-sha256.h>
#include "fmp_fips_info.h"
#include "fips140_ic_support.h"
#define FIPS_HMAC_SIZE 32
#define FIPS_CHECK_INTEGRITY
#undef FIPS_DEBUG_INTEGRITY
/* Same as build time */
static const unsigned char *integrity_check_key =
"The quick brown fox jumps over the lazy dog";
#ifdef FIPS_DEBUG_INTEGRITY
void show_emebedded_info(void)
{
int i = 0;
int j = 0;
for (i = 0; i < fips140_sec_amount; i++) {
pr_info("Section #%d\n", i);
pr_info(" anchor symbols addr/offset %llx/%d\n",
fips140_get_anchor_addr(i), fips140_anchor_offset[i]);
}
pr_info(" Chunks amount: %d\n", fips140_chunk_amount);
for (j = 0; j < fips140_chunk_amount; j++) {
pr_info("[ chunk #%d, sec: %d start: %d end: %d ]",
j,
fips140_chunks_info[j].sec_no,
fips140_chunks_info[j].chunk_start,
fips140_chunks_info[j].chunk_end);
}
}
#endif
int do_fmp_integrity_check(struct exynos_fmp *fmp)
{
int err = 0;
uint8_t *start_addr = NULL;
unsigned char runtime_hmac[FIPS_HMAC_SIZE];
uint32_t sec_idx = 0;
uint8_t *sec_zero_addr = NULL;
uint32_t ch = 0;
uint32_t size = 0;
struct hmac_sha256_ctx ctx;
const char *builtime_hmac = 0;
#ifndef FIPS_CHECK_INTEGRITY
return 0;
#endif
#ifdef FIPS_DEBUG_INTEGRITY
show_emebedded_info();
#endif
if (!fmp || !fmp->dev) {
pr_err("%s: invalid fmp device\n", __func__);
return -EINVAL;
}
memset(runtime_hmac, 0x00, 32);
err = hmac_sha256_init(&ctx,
integrity_check_key,
strlen(integrity_check_key));
if (err) {
pr_err("FIPS(%s): init_hash failed\n", __func__);
return -1;
}
for (sec_idx = 0; sec_idx < fips140_sec_amount; sec_idx++) {
sec_zero_addr = (uint8_t *)(fips140_get_anchor_addr(sec_idx)
- fips140_anchor_offset[sec_idx]);
for (ch = 0; ch < fips140_chunk_amount; ch++) {
if (fips140_chunks_info[ch].sec_no != sec_idx)
continue;
start_addr = fips140_chunks_info[ch].chunk_start
+ sec_zero_addr;
size = fips140_chunks_info[ch].chunk_end
- fips140_chunks_info[ch].chunk_start
+ 1;
#ifdef FIPS_DEBUG_INTEGRITY
print_hex_dump(KERN_ERR, " FIPS_chunks >>> : ",
DUMP_PREFIX_ADDRESS, 16, 1, start_addr, size, false);
#endif
err = hmac_sha256_update(&ctx, start_addr, size);
if (err) {
pr_err("FIPS(%s): Error to update hash",
__func__);
return -1;
}
}
}
err = hmac_sha256_final(&ctx, runtime_hmac);
if (err) {
pr_err("FIPS(%s): Error in finalize", __func__);
hmac_sha256_ctx_cleanup(&ctx);
return -1;
}
hmac_sha256_ctx_cleanup(&ctx);
builtime_hmac = fips140_builtime_hmac;
#ifdef FIPS_DEBUG_INTEGRITY
print_hex_dump(KERN_INFO, "FIPS FMP RUNTIME : runtime hmac = ",
DUMP_PREFIX_NONE, 16, 1, runtime_hmac, sizeof(runtime_hmac), false);
print_hex_dump(KERN_INFO, "FIPS FMP RUNTIME : builtime_hmac = ",
DUMP_PREFIX_NONE, 16, 1, builtime_hmac, sizeof(runtime_hmac), false);
#endif
if (!memcmp(builtime_hmac, runtime_hmac, sizeof(runtime_hmac))) {
pr_info("FIPS(%s): Integrity Check Passed", __func__);
return 0;
}
pr_err("FIPS(%s): Integrity Check Failed", __func__);
return -1;
}