--- /dev/null
+/* 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;
+ }
+}