+/* hmac-sha256.c */
+/*
+ This file is part of the AVR-Crypto-Lib.
+ Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
+
+ 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/>.
+*/
/**
*
* implementation of HMAC as described in RFC2104
- * Author: Daniel Otte
- *
- * License: GPL
+ * Author: Daniel Otte
+ * email: daniel.otte@rub.de
+ * License: GPLv3 or later
**/
/*
#include <string.h>
#include "config.h"
#include "sha256.h"
+#include "hmac-sha256.h"
#define IPAD 0x36
#define OPAD 0x5C
-typedef sha256_ctx_t hmac_sha256_ctx_t;
+#ifndef HMAC_SHA256_SHORTONLY
-#ifndef HMAC_SHORTONLY
-
-void hmac_sha256_init(hmac_sha256_ctx_t *s, void* key, uint16_t kl){
- uint8_t buffer[SHA256_BLOCK_BITS/8];
+void hmac_sha256_init(hmac_sha256_ctx_t *s, const void* key, uint16_t keylength_b){
+ uint8_t buffer[HMAC_SHA256_BLOCK_BYTES];
uint8_t i;
- if (kl > SHA256_BLOCK_BITS){
- sha256((void*)buffer, key, kl);
+ memset(buffer, 0, HMAC_SHA256_BLOCK_BYTES);
+ if (keylength_b > HMAC_SHA256_BLOCK_BITS){
+ sha256((void*)buffer, key, keylength_b);
} else {
- memcpy(buffer, key, (kl+7/8));
+ memcpy(buffer, key, (keylength_b+7)/8);
}
- for (i=0; i<SHA256_BLOCK_BITS/8; ++i){
+ for (i=0; i<HMAC_SHA256_BLOCK_BYTES; ++i){
buffer[i] ^= IPAD;
}
- sha256_init(s);
- sha256_nextBlock(s, buffer);
+ sha256_init(&(s->a));
+ sha256_nextBlock(&(s->a), buffer);
+
+ for (i=0; i<HMAC_SHA256_BLOCK_BYTES; ++i){
+ buffer[i] ^= IPAD^OPAD;
+ }
+ sha256_init(&(s->b));
+ sha256_nextBlock(&(s->b), buffer);
+
#if defined SECURE_WIPE_BUFFER
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
+ memset(buffer, 0, SHA256_BLOCK_BYTES);
#endif
}
-void hmac_sha256_final(hmac_sha256_ctx_t *s, void* key, uint16_t kl){
- uint8_t buffer[SHA256_BLOCK_BITS/8];
- uint8_t i;
- sha256_ctx_t a;
-
- if (kl > SHA256_BLOCK_BITS){
- sha256((void*)buffer, key, kl);
- } else {
- memcpy(buffer, key, (kl+7)/8);
- }
-
- for (i=0; i<SHA256_BLOCK_BITS/8; ++i){
- buffer[i] ^= OPAD;
+void hmac_sha256_nextBlock(hmac_sha256_ctx_t *s, const void* block){
+ sha256_nextBlock(&(s->a), block);
+}
+
+void hmac_sha256_lastBlock(hmac_sha256_ctx_t *s, const void* block, uint16_t length_b){
+/* while(length_b>=SHA256_BLOCK_BITS){
+ sha256_nextBlock(&(s->a), block);
+ block = (uint8_t*)block + SHA256_BLOCK_BYTES;
+ length_b -= SHA256_BLOCK_BITS;
}
-
- sha256_init(&a);
- sha256_nextBlock(&a, buffer); /* hash key ^ opad */
- sha256_ctx2hash((void*)buffer, s); /* copy hash(key ^ ipad, msg) to buffer */
- sha256_lastBlock(s, buffer, SHA256_HASH_BITS);
-#if defined SECURE_WIPE_BUFFER
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
- memset(a.h, 0, 8*4);
-#endif
+*/ sha256_lastBlock(&(s->a), block, length_b);
}
-#endif
+void hmac_sha256_final(void* dest, hmac_sha256_ctx_t *s){
+ sha256_ctx2hash((sha256_hash_t*)dest, &(s->a));
+ sha256_lastBlock(&(s->b), dest, SHA256_HASH_BITS);
+ sha256_ctx2hash((sha256_hash_t*)dest, &(s->b));
+}
-/*
-void hmac_sha256_nextBlock()
-void hmac_sha256_lastBlock()
-*/
+#endif
/*
* keylength in bits!
* message length in bits!
*/
-void hmac_sha256(void* dest, void* key, uint16_t kl, void* msg, uint64_t ml){ /* a one-shot*/
+void hmac_sha256(void* dest, const void* key, uint16_t keylength_b, const void* msg, uint32_t msglength_b){ /* a one-shot*/
sha256_ctx_t s;
uint8_t i;
- uint8_t buffer[SHA256_BLOCK_BITS/8];
+ uint8_t buffer[HMAC_SHA256_BLOCK_BYTES];
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
+ memset(buffer, 0, HMAC_SHA256_BLOCK_BYTES);
/* if key is larger than a block we have to hash it*/
- if (kl > SHA256_BLOCK_BITS){
- sha256((void*)buffer, key, kl);
+ if (keylength_b > SHA256_BLOCK_BITS){
+ sha256((void*)buffer, key, keylength_b);
} else {
- memcpy(buffer, key, (kl+7)/8);
+ memcpy(buffer, key, (keylength_b+7)/8);
}
- for (i=0; i<SHA256_BLOCK_BITS/8; ++i){
+ for (i=0; i<SHA256_BLOCK_BYTES; ++i){
buffer[i] ^= IPAD;
}
sha256_init(&s);
sha256_nextBlock(&s, buffer);
- while (ml >= SHA256_BLOCK_BITS){
+ while (msglength_b >= HMAC_SHA256_BLOCK_BITS){
sha256_nextBlock(&s, msg);
- msg = (uint8_t*)msg + SHA256_BLOCK_BITS/8;
- ml -= SHA256_BLOCK_BITS;
+ msg = (uint8_t*)msg + HMAC_SHA256_BLOCK_BYTES;
+ msglength_b -= HMAC_SHA256_BLOCK_BITS;
}
- sha256_lastBlock(&s, msg, ml);
+ sha256_lastBlock(&s, msg, msglength_b);
/* since buffer still contains key xor ipad we can do ... */
- for (i=0; i<SHA256_BLOCK_BITS/8; ++i){
+ for (i=0; i<HMAC_SHA256_BLOCK_BYTES; ++i){
buffer[i] ^= IPAD ^ OPAD;
}
sha256_ctx2hash(dest, &s); /* save inner hash temporary to dest */
projects / avr-crypto-lib.git / blobdiff