3 This file is part of the ARM-Crypto-Lib.
4 Copyright (C) 2006-2010 Daniel Otte (daniel.otte@rub.de)
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
27 * \brief SHA-256 implementation.
33 #include <string.h> /* for memcpy, memmove, memset */
34 #include <avr/pgmspace.h>
35 #include "sha2_small_common.h"
40 #if defined LITTLE_ENDIAN
41 #elif defined BIG_ENDIAN
43 #error specify endianess!!!
47 /*************************************************************************/
50 uint32_t sha256_init_vector[] PROGMEM = {
51 0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A,
52 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19 };
55 /*************************************************************************/
58 * \brief \c sh256_init initialises a sha256 context for hashing.
59 * \c sh256_init c initialises the given sha256 context for hashing
60 * @param state pointer to a sha256 context
63 void sha256_init(sha256_ctx_t *state){
65 memcpy_P(state->h, sha256_init_vector, 8*4);
68 /*************************************************************************/
69 void sha256_nextBlock (sha256_ctx_t *state, const void *block){
70 sha2_small_common_nextBlock(state, block);
73 /*************************************************************************/
74 void sha256_lastBlock (sha256_ctx_t *state, const void *block, uint16_t length_b){
75 sha2_small_common_lastBlock(state, block, length_b);
77 /*************************************************************************/
80 * \brief function to process the last block being hashed
81 * @param state Pointer to the context in which this block should be processed.
82 * @param block Pointer to the message wich should be hashed.
83 * @param length is the length of only THIS block in BITS not in bytes!
84 * bits are big endian, meaning high bits come first.
85 * if you have a message with bits at the end, the byte must be padded with zeros
88 /*************************************************************************/
93 void sha256(void *dest, const void *msg, uint32_t length_b){ /* length could be choosen longer but this is for µC */
96 while(length_b >= SHA256_BLOCK_BITS){
97 sha256_nextBlock(&s, msg);
98 msg = (uint8_t*)msg + SHA256_BLOCK_BITS/8;
99 length_b -= SHA256_BLOCK_BITS;
101 sha256_lastBlock(&s, msg, length_b);
102 sha256_ctx2hash(dest,&s);
107 /*************************************************************************/
109 void sha256_ctx2hash(void *dest, const sha256_ctx_t *state){
110 #if defined LITTLE_ENDIAN
111 uint8_t i, j, *s=(uint8_t*)(state->h);
116 *((uint8_t*)dest) = s[j];
117 dest = (uint8_t*)dest + 1;
122 memcpy(dest, state->h, 32);
124 # error unsupported endian type!