X-Git-Url: https://git.cryptolib.org/?p=avr-crypto-lib.git;a=blobdiff_plain;f=hfal%2Fhfal-hmac.c;fp=hfal%2Fhfal-hmac.c;h=dbc56088ec0163fab8deb8f7a91724250a3270ed;hp=0000000000000000000000000000000000000000;hb=924aa320bef6f192feecdb67d209c790bd49ea49;hpb=fb4cf7b5c6e5f28d886bd4216f09b8052c7bd013

diff --git a/hfal/hfal-hmac.c b/hfal/hfal-hmac.c
new file mode 100644
index 0000000..dbc5608
--- /dev/null
+++ b/hfal/hfal-hmac.c
@@ -0,0 +1,127 @@
+/* hfal-hmac.c */
+/*
+    This file is part of the AVR-Crypto-Lib.
+    Copyright (C) 2009  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/>.
+*/
+
+#include <avr/pgmspace.h>
+#include "hashfunction_descriptor.h"
+#include "hfal-basic.h"
+#include <stdlib.h>
+
+#define IPAD 0x36
+#define OPAD 0x5C
+
+uint8_t hfal_hmac_init(const hfdesc_t* hash_descriptor, 
+                       hfhmacgen_ctx_t* ctx, 
+					   const void* key, uint16_t keylength_b){
+	uint16_t  bs = hfal_hash_getBlocksize();
+	uint8_t buffer[bs/8];
+	uint8_t i;
+	hf_init_fpt init;
+	hf_nextBlock_fpt nextBlock;
+	memset(buffer, 0, bs/8);
+	ctx->desc   = hash_descriptor;
+	ctx->ctx    = malloc(pgm_read_word(&(hash_descriptor->ctxsize_B)));
+	ctx->finctx = malloc(pgm_read_word(&(hash_descriptor->ctxsize_B)));
+	if(ctx->ctx==NULL && ctx->finctx==NULL)
+		return 3;
+	if(ctx->finctx==NULL){
+		free(ctx->ctx)
+		return 2;
+	}
+	if(ctx->ctx==NULL){
+		free(ctx->finctx)
+		return 1;
+	}		
+	if(keylength_b>bs){
+		hfal_hash_mem(hash_descriptor, buffer, key, keylength_b);
+	} else {
+		memcpy(buffer, key, (keylength_b+7)/8);
+	}
+	for(i=0; i<bs/8; ++i){
+		buffer[i] ^= IPAD;
+	}
+	init = pgm_read_word(&(hash_descriptor->init));
+	nextBlock = pgm_read_word(&(hash_descriptor->nextBlock));
+	init(ctx->ctx);
+	init(ctx->finctx);
+	nextBlock(ctx->ctx, buffer);
+	for(i=0; i<bs/8; ++i){
+		buffer[i] ^= IPAD^OPAD;
+	}
+	nextBlock(ctx->finctx, buffer);
+	memset(buffer, 0, bs/8);
+}
+					   
+void hfal_hmac_nextBlock(hfhmacgen_ctx_t* ctx, const void* block){
+	hf_nextBlock_fpt nextBlock;
+	nextBlock = pgm_read_word(&(hash_descriptor->nextBlock));
+	nextBlock(ctx->ctx, block);
+}
+
+void hfal_hmac_lastBlock(hfhmacgen_ctx_t* ctx, const void* block, uint16_t length_b){
+	hf_lastBlock_fpt lastBlock;
+	hf_ctx2hash_fpt  ctx2hash;
+	uint16_t hs = pgm_read_word(&(hash_descriptor->hashsize_b));
+	uint8_t buffer[(hs+7)/8];
+	lastBlock = pgm_read_word(&(hash_descriptor->lastBlock));
+	ctx2hash = pgm_read_word(&(hash_descriptor->ctx2hash));
+	lastBlock(ctx->ctx, block, length_b);
+	ctx2hash(buffer, ctx->ctx);
+	lastBlock(ctx->finctx, buffer, hs);
+}
+
+void hfal_hmac_ctx2mac(void* dest, hfhmacgen_ctx_t* ctx){
+	hf_ctx2hash_fpt  ctx2hash;
+	ctx2hash = pgm_read_word(&(hash_descriptor->ctx2hash));
+	ctx2hash(dest, ctx->finctx);
+}
+
+void hfal_hmac_free(hfhmacgen_ctx_t* ctx){
+	hf_free_fpt free_fpt;
+	free_fpt = pgm_read_word(&(hash_descriptor->free));
+	if(free_fpt){
+		free_fpt(ctx->ctx);
+		free_fpt(ctx->finctx);
+	}
+	free(ctx->ctx)
+	free(ctx->finctx)
+}
+
+void hfal_hmac_mem(const hfdesc_t* hash_descriptor, const void* key, uint16_t keylength_b, void* dest, const void* msg, uint32_t length_b){
+	hfhmacgen_ctx_t ctx;
+	uint16_t  bs = hfal_hash_getBlocksize();
+	hfal_hmac_init(hash_descriptor, &ctx, key, keylength_b);
+	while(length_b>bs){
+		hfal_hmac_nextBlock(&ctx, msg);
+		msg = msg + bs/8;
+		length_b-=bs;
+	}
+	hfal_hmac_lastBlock(&ctx, msg, length_b);
+	hfal_hmac_ctx2mac(dest, &ctx);
+	hfal_free(&ctx);
+}
+
+uint16_t hfal_hmac_getBlocksize(const hfdesc_t* hash_descriptor){
+	return hfal_hash_getBlocksize(hash_descriptor);
+}
+
+uint16_t hfal_hmac_getMACsize(const hfdesc_t* hash_descriptor){
+	return hfal_hash_getHashsize(hash_descriptor);
+}
+
+