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/*
* FIPS-180-2 compliant SHA-256 implementation
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* The SHA-256 Secure Hash Standard was published by NIST in 2002.
*
* http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
*/
#include "../common.h"
#if defined(MBEDTLS_SHA256_C)
#include "mbedtls/sha256.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
#include <string.h>
#include "mbedtls/platform.h"
#if defined(MBEDTLS_SHA256_ALT)
#define SHA256_BLOCK_SIZE 64
static struct sha_dev *sha = NULL;
void mbedtls_sha256_init(mbedtls_sha256_context *ctx)
{
memset(ctx, 0, sizeof(mbedtls_sha256_context));
}
void mbedtls_sha256_free(mbedtls_sha256_context *ctx)
{
if (ctx == NULL) {
return;
}
mbedtls_platform_zeroize(ctx, sizeof(mbedtls_sha256_context));
}
void mbedtls_sha256_clone(mbedtls_sha256_context *dst,
const mbedtls_sha256_context *src)
{
*dst = *src;
}
/*
* SHA-256 context setup
*/
int mbedtls_sha256_starts(mbedtls_sha256_context *ctx, int is224)
{
#if defined(MBEDTLS_SHA224_C) && defined(MBEDTLS_SHA256_C)
if (is224 != 0 && is224 != 1) {
return MBEDTLS_ERR_SHA256_BAD_INPUT_DATA;
}
#elif defined(MBEDTLS_SHA256_C)
if (is224 != 0) {
return MBEDTLS_ERR_SHA256_BAD_INPUT_DATA;
}
#else /* defined MBEDTLS_SHA224_C only */
if (is224 == 0) {
return MBEDTLS_ERR_SHA256_BAD_INPUT_DATA;
}
#endif
ctx->total[0] = 0;
ctx->total[1] = 0;
if (is224 == 0) {
#if defined(MBEDTLS_SHA256_C)
ctx->state[0] = 0x6A09E667;
ctx->state[1] = 0xBB67AE85;
ctx->state[2] = 0x3C6EF372;
ctx->state[3] = 0xA54FF53A;
ctx->state[4] = 0x510E527F;
ctx->state[5] = 0x9B05688C;
ctx->state[6] = 0x1F83D9AB;
ctx->state[7] = 0x5BE0CD19;
#endif
} else {
#if defined(MBEDTLS_SHA224_C)
ctx->state[0] = 0xC1059ED8;
ctx->state[1] = 0x367CD507;
ctx->state[2] = 0x3070DD17;
ctx->state[3] = 0xF70E5939;
ctx->state[4] = 0xFFC00B31;
ctx->state[5] = 0x68581511;
ctx->state[6] = 0x64F98FA7;
ctx->state[7] = 0xBEFA4FA4;
#endif
}
#if defined(MBEDTLS_SHA224_C)
ctx->is224 = is224;
#endif
return 0;
}
int mbedtls_internal_sha256_process(mbedtls_sha256_context *ctx,
const unsigned char data[64])
{
if (!sha) {
sha = (struct sha_dev *)dev_get(HG_SHA_DEVID);
}
struct sha_req req = {
.type = T_SHA256,
.len = 64,
.state = ctx->state,
.input = (void *)data,
};
sha_xform(sha, &req);
return 0;
}
int mbedtls_internal_sha256_process_many(mbedtls_sha256_context *ctx,
const unsigned char *input,
uint32_t ilen)
{
if (!sha) {
sha = (struct sha_dev *)dev_get(HG_SHA_DEVID);
}
struct sha_req req = {
.type = T_SHA256,
.len = ilen & ~(64-1),
.state = ctx->state,
.input = (void *)input,
};
sha_xform(sha, &req);
return req.len;
}
/*
* SHA-256 process buffer
*/
int mbedtls_sha256_update(mbedtls_sha256_context *ctx,
const unsigned char *input,
size_t ilen)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t fill;
uint32_t left;
if (ilen == 0) {
return 0;
}
left = ctx->total[0] & 0x3F;
fill = SHA256_BLOCK_SIZE - left;
ctx->total[0] += (uint32_t) ilen;
ctx->total[0] &= 0xFFFFFFFF;
if (ctx->total[0] < (uint32_t) ilen) {
ctx->total[1]++;
}
if (left && ilen >= fill) {
memcpy((void *) (ctx->buffer + left), input, fill);
if ((ret = mbedtls_internal_sha256_process(ctx, ctx->buffer)) != 0) {
return ret;
}
input += fill;
ilen -= fill;
left = 0;
}
while (ilen >= SHA256_BLOCK_SIZE) {
size_t processed =
mbedtls_internal_sha256_process_many(ctx, input, ilen);
if (processed < SHA256_BLOCK_SIZE) {
return MBEDTLS_ERR_ERROR_GENERIC_ERROR;
}
input += processed;
ilen -= processed;
}
if (ilen > 0) {
memcpy((void *) (ctx->buffer + left), input, ilen);
}
return 0;
}
/*
* SHA-256 final digest
*/
int mbedtls_sha256_finish(mbedtls_sha256_context *ctx,
unsigned char *output)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
uint32_t used;
uint32_t high, low;
/*
* Add padding: 0x80 then 0x00 until 8 bytes remain for the length
*/
used = ctx->total[0] & 0x3F;
ctx->buffer[used++] = 0x80;
if (used <= 56) {
/* Enough room for padding + length in current block */
memset(ctx->buffer + used, 0, 56 - used);
} else {
/* We'll need an extra block */
memset(ctx->buffer + used, 0, SHA256_BLOCK_SIZE - used);
if ((ret = mbedtls_internal_sha256_process(ctx, ctx->buffer)) != 0) {
return ret;
}
memset(ctx->buffer, 0, 56);
}
/*
* Add message length
*/
high = (ctx->total[0] >> 29)
| (ctx->total[1] << 3);
low = (ctx->total[0] << 3);
MBEDTLS_PUT_UINT32_BE(high, ctx->buffer, 56);
MBEDTLS_PUT_UINT32_BE(low, ctx->buffer, 60);
if ((ret = mbedtls_internal_sha256_process(ctx, ctx->buffer)) != 0) {
return ret;
}
/*
* Output final state
*/
MBEDTLS_PUT_UINT32_BE(ctx->state[0], output, 0);
MBEDTLS_PUT_UINT32_BE(ctx->state[1], output, 4);
MBEDTLS_PUT_UINT32_BE(ctx->state[2], output, 8);
MBEDTLS_PUT_UINT32_BE(ctx->state[3], output, 12);
MBEDTLS_PUT_UINT32_BE(ctx->state[4], output, 16);
MBEDTLS_PUT_UINT32_BE(ctx->state[5], output, 20);
MBEDTLS_PUT_UINT32_BE(ctx->state[6], output, 24);
int truncated = 0;
#if defined(MBEDTLS_SHA224_C)
truncated = ctx->is224;
#endif
if (!truncated) {
MBEDTLS_PUT_UINT32_BE(ctx->state[7], output, 28);
}
return 0;
}
#endif /* !MBEDTLS_SHA256_ALT */
#endif /* MBEDTLS_SHA256_C */