X-Git-Url: https://git.cryptolib.org/?p=arm-crypto-lib.git;a=blobdiff_plain;f=bcal%2Fbcal-cfb_bit.c;fp=bcal%2Fbcal-cfb_bit.c;h=6ddb57fcce8cf271b1b16083efe106d8ef47760e;hp=0000000000000000000000000000000000000000;hb=d70d1d77bab1a5f5278227d674bc59da0378fe15;hpb=d00ed9a275c69fa3512007452e479abd98dbe745

diff --git a/bcal/bcal-cfb_bit.c b/bcal/bcal-cfb_bit.c
new file mode 100644
index 0000000..6ddb57f
--- /dev/null
+++ b/bcal/bcal-cfb_bit.c
@@ -0,0 +1,128 @@
+/* bcal-cfb_bit.c */
+/*
+    This file is part of the ARM-Crypto-Lib.
+    Copyright (C) 2006-2010  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 <stdint.h>
+#include <string.h>
+#include "bcal-cfb_bit.h"
+#include "bcal-basic.h"
+
+static uint8_t read_bit(void* block, uint32_t index){
+	uint8_t r;
+	r=((uint8_t*)block)[index/8];
+	r=(r&(0x80>>(index&7)))?0xff:0x00;
+	return r;
+}
+
+static void write_bit(void* block, uint32_t index, uint8_t value){
+	if(value){
+		/* set bit */
+		((uint8_t*)block)[index/8] |= 0x80>>(index&7);
+	}else{
+		/* clear bit */
+		((uint8_t*)block)[index/8] &= ~(0x80>>(index&7));
+	}
+}
+
+uint8_t bcal_cfb_b_init(const bcdesc_t* desc, const void* key, uint16_t keysize_b, uint16_t size_b, bcal_cfb_b_ctx_t* ctx){
+	ctx->desc = (bcdesc_t*)desc;
+	ctx->blocksize_B = (bcal_cipher_getBlocksize_b(desc)+7)/8;
+	ctx->in_block=malloc(ctx->blocksize_B);
+	if(ctx->in_block==NULL){
+		return 0x11;
+	}
+	if(size_b>bcal_cipher_getBlocksize_b(desc)){
+		return 0x12;
+	}
+	ctx->size_b = size_b;
+	return bcal_cipher_init(desc, key, keysize_b, &(ctx->cctx));
+}
+
+void bcal_cfb_b_free(bcal_cfb_b_ctx_t* ctx){
+	free(ctx->in_block);
+	bcal_cipher_free(&(ctx->cctx));
+}
+
+void bcal_cfb_b_loadIV(const void* iv, bcal_cfb_b_ctx_t* ctx){
+	if(iv){
+		memcpy(ctx->in_block, iv, ctx->blocksize_B);
+	}
+}
+
+void bcal_cfb_b_encNext(void* block, uint8_t offset, bcal_cfb_b_ctx_t* ctx){
+	uint8_t tmp[ctx->blocksize_B];
+	offset &= 7;
+	memcpy(tmp, ctx->in_block, ctx->blocksize_B);
+	bcal_cipher_enc(tmp, &(ctx->cctx));
+	uint16_t i,j;
+	uint8_t a;
+	for(i=0; i<ctx->blocksize_B*8-ctx->size_b; ++i){
+		a = read_bit(ctx->in_block, i+ctx->size_b);
+		write_bit(ctx->in_block, i, a);
+	}
+	for(j=offset,i=0; i<ctx->size_b; ++i, ++j){
+		a = read_bit(tmp, i) ^ read_bit(block, j);
+		write_bit(ctx->in_block, ctx->blocksize_B*8-ctx->size_b+i, a);
+		write_bit(block, j, a);
+	}
+}
+
+void bcal_cfb_b_decNext(void* block, uint8_t offset, bcal_cfb_b_ctx_t* ctx){
+	uint8_t tmp[ctx->blocksize_B];
+	offset &= 7;
+	memcpy(tmp, ctx->in_block, ctx->blocksize_B);
+	bcal_cipher_enc(tmp, &(ctx->cctx));
+	uint16_t i,j;
+	uint8_t a,b;
+	for(i=0; i<ctx->blocksize_B*8-ctx->size_b; ++i){
+		a = read_bit(ctx->in_block, i+ctx->size_b);
+		write_bit(ctx->in_block, i, a);
+	}
+	for(j=offset,i=0; i<ctx->size_b; ++i, ++j){
+		a = read_bit(tmp, i);
+		b = read_bit(block, j);
+		a ^= b;
+		write_bit(ctx->in_block, ctx->blocksize_B*8-ctx->size_b+i, b);
+		write_bit(block, j, a);
+	}
+}
+
+void bcal_cfb_b_encMsg(const void* iv, void* msg, uint8_t offset, uint32_t msg_blocks, bcal_cfb_b_ctx_t* ctx){
+	bcal_cfb_b_loadIV(iv, ctx);
+	uint64_t addr;
+	addr = ((uint32_t)msg)*8+offset;
+	while(msg_blocks--){
+		msg = (void*)((uint32_t)(addr/8));
+		offset = addr&7;
+		bcal_cfb_b_encNext(msg, offset, ctx);
+		addr += ctx->size_b;
+	}
+}
+
+void bcal_cfb_b_decMsg(const void* iv, void* msg, uint8_t offset, uint32_t msg_blocks, bcal_cfb_b_ctx_t* ctx){
+	bcal_cfb_b_loadIV(iv, ctx);
+	uint64_t addr;
+	addr = ((uint32_t)msg)*8+offset;
+	while(msg_blocks--){
+		msg = (void*)((uint32_t)(addr/8));
+		offset = addr&7;
+		bcal_cfb_b_decNext(msg, offset, ctx);
+		addr += ctx->size_b;
+	}
+}