mirror of
https://github.com/DarkFlippers/unleashed-firmware
synced 2024-12-21 02:03:18 +00:00
98 lines
3.4 KiB
C
98 lines
3.4 KiB
C
/*
|
|
* hmac.c - HMAC
|
|
*
|
|
* Copyright (C) 2017 Sergei Glushchenko
|
|
* Author: Sergei Glushchenko <gl.sergei@gmail.com>
|
|
*
|
|
* This file is a part of U2F firmware for STM32
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* As additional permission under GNU GPL version 3 section 7, you may
|
|
* distribute non-source form of the Program without the copy of the
|
|
* GNU GPL normally required by section 4, provided you inform the
|
|
* recipients of GNU GPL by a written offer.
|
|
*
|
|
*/
|
|
#include <stdint.h>
|
|
|
|
#include "sha256.h"
|
|
#include "hmac_sha256.h"
|
|
|
|
static void _hmac_sha256_init(const hmac_context* ctx) {
|
|
hmac_sha256_context* context = (hmac_sha256_context*)ctx;
|
|
sha256_start(&context->sha_ctx);
|
|
}
|
|
|
|
static void
|
|
_hmac_sha256_update(const hmac_context* ctx, const uint8_t* message, unsigned message_size) {
|
|
hmac_sha256_context* context = (hmac_sha256_context*)ctx;
|
|
sha256_update(&context->sha_ctx, message, message_size);
|
|
}
|
|
|
|
static void _hmac_sha256_finish(const hmac_context* ctx, uint8_t* hash_result) {
|
|
hmac_sha256_context* context = (hmac_sha256_context*)ctx;
|
|
sha256_finish(&context->sha_ctx, hash_result);
|
|
}
|
|
|
|
/* Compute an HMAC using K as a key (as in RFC 6979). Note that K is always
|
|
the same size as the hash result size. */
|
|
static void hmac_init(const hmac_context* ctx, const uint8_t* K) {
|
|
uint8_t* pad = ctx->tmp + 2 * ctx->result_size;
|
|
unsigned i;
|
|
for(i = 0; i < ctx->result_size; ++i) pad[i] = K[i] ^ 0x36;
|
|
for(; i < ctx->block_size; ++i) pad[i] = 0x36;
|
|
|
|
ctx->init_hash(ctx);
|
|
ctx->update_hash(ctx, pad, ctx->block_size);
|
|
}
|
|
|
|
static void hmac_update(const hmac_context* ctx, const uint8_t* message, unsigned message_size) {
|
|
ctx->update_hash(ctx, message, message_size);
|
|
}
|
|
|
|
static void hmac_finish(const hmac_context* ctx, const uint8_t* K, uint8_t* result) {
|
|
uint8_t* pad = ctx->tmp + 2 * ctx->result_size;
|
|
unsigned i;
|
|
for(i = 0; i < ctx->result_size; ++i) pad[i] = K[i] ^ 0x5c;
|
|
for(; i < ctx->block_size; ++i) pad[i] = 0x5c;
|
|
|
|
ctx->finish_hash(ctx, result);
|
|
|
|
ctx->init_hash(ctx);
|
|
ctx->update_hash(ctx, pad, ctx->block_size);
|
|
ctx->update_hash(ctx, result, ctx->result_size);
|
|
ctx->finish_hash(ctx, result);
|
|
}
|
|
|
|
void hmac_sha256_init(hmac_sha256_context* ctx, const uint8_t* K) {
|
|
ctx->hmac_ctx.init_hash = _hmac_sha256_init;
|
|
ctx->hmac_ctx.update_hash = _hmac_sha256_update;
|
|
ctx->hmac_ctx.finish_hash = _hmac_sha256_finish;
|
|
ctx->hmac_ctx.block_size = 64;
|
|
ctx->hmac_ctx.result_size = 32;
|
|
ctx->hmac_ctx.tmp = ctx->tmp;
|
|
hmac_init(&ctx->hmac_ctx, K);
|
|
}
|
|
|
|
void hmac_sha256_update(
|
|
const hmac_sha256_context* ctx,
|
|
const uint8_t* message,
|
|
unsigned message_size) {
|
|
hmac_update(&ctx->hmac_ctx, message, message_size);
|
|
}
|
|
|
|
void hmac_sha256_finish(const hmac_sha256_context* ctx, const uint8_t* K, uint8_t* hash_result) {
|
|
hmac_finish(&ctx->hmac_ctx, K, hash_result);
|
|
}
|