+/* hmac-sha256.c */
+/*
+ This file is part of the Crypto-avr-lib/microcrypt-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
**/
/*
#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, void* key, uint16_t keylength_b){
+ uint8_t buffer[SHA256_HASH_BYTES];
uint8_t i;
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
- if (kl > SHA256_BLOCK_BITS){
- sha256((void*)buffer, key, kl);
+ memset(buffer, 0, SHA256_HASH_BYTES);
+ 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_HASH_BYTES; ++i){
buffer[i] ^= IPAD;
}
sha256_init(s);
sha256_nextBlock(s, buffer);
#if defined SECURE_WIPE_BUFFER
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
+ memset(buffer, 0, SHA256_HASH_BYTES);
#endif
}
-void hmac_sha256_final(hmac_sha256_ctx_t *s, void* key, uint16_t kl){
- uint8_t buffer[SHA256_BLOCK_BITS/8];
+void hmac_sha256_final(hmac_sha256_ctx_t *s, void* key, uint16_t keylength_b){
+ uint8_t buffer[SHA256_HASH_BYTES];
uint8_t i;
sha256_ctx_t a;
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
- if (kl > SHA256_BLOCK_BITS){
- sha256((void*)buffer, key, kl);
+ memset(buffer, 0, SHA256_HASH_BYTES);
+ 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_HASH_BYTES; ++i){
buffer[i] ^= OPAD;
}
sha256_lastBlock(&a, buffer, SHA256_HASH_BITS);
memcpy(s, &a, sizeof(sha256_ctx_t));
#if defined SECURE_WIPE_BUFFER
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
+ memset(buffer, 0, SHA256_HASH_BYTES);
memset(a.h, 0, 8*4);
#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, void* key, uint16_t keylength_b, void* msg, uint64_t msglength_b){ /* a one-shot*/
sha256_ctx_t s;
uint8_t i;
- uint8_t buffer[SHA256_BLOCK_BITS/8];
+ uint8_t buffer[SHA256_HASH_BYTES];
- memset(buffer, 0, SHA256_BLOCK_BITS/8);
+ memset(buffer, 0, SHA256_HASH_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_HASH_BYTES; ++i){
buffer[i] ^= IPAD;
}
sha256_init(&s);
sha256_nextBlock(&s, buffer);
- while (ml >= SHA256_BLOCK_BITS){
+ while (msglength_b >= SHA256_BLOCK_BITS){
sha256_nextBlock(&s, msg);
- msg = (uint8_t*)msg + SHA256_BLOCK_BITS/8;
- ml -= SHA256_BLOCK_BITS;
+ msg = (uint8_t*)msg + SHA256_HASH_BYTES;
+ msglength_b -= 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<SHA256_HASH_BYTES; ++i){
buffer[i] ^= IPAD ^ OPAD;
}
sha256_ctx2hash(dest, &s); /* save inner hash temporary to dest */