3 This file is part of the AVR-Crypto-Lib.
4 Copyright (C) 2006-2015 Daniel Otte (bg@nerilex.org)
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include "bcal-cfb_byte.h"
23 #include "bcal-basic.h"
26 uint8_t bcal_cfb_B_init(const bcdesc_t *desc, const void *key,
27 uint16_t keysize_b, uint16_t size_b, bcal_cfb_B_ctx_t *ctx)
29 ctx->desc = (bcdesc_t*) desc;
30 ctx->blocksize_B = (bcal_cipher_getBlocksize_b(desc) + 7) / 8;
31 ctx->in_block = malloc(ctx->blocksize_B);
32 if (ctx->in_block == NULL) {
38 ctx->size_B = size_b / 8;
39 return bcal_cipher_init(desc, key, keysize_b, &(ctx->cctx));
42 void bcal_cfb_B_free(bcal_cfb_B_ctx_t *ctx)
45 bcal_cipher_free(&(ctx->cctx));
48 void bcal_cfb_B_loadIV(const void *iv, bcal_cfb_B_ctx_t *ctx)
51 memcpy(ctx->in_block, iv, ctx->blocksize_B);
55 void bcal_cfb_B_encNext(void *block, bcal_cfb_B_ctx_t *ctx)
57 uint8_t tmp[ctx->blocksize_B];
58 memcpy(tmp, ctx->in_block, ctx->blocksize_B);
59 bcal_cipher_enc(tmp, &(ctx->cctx));
60 memxor(block, tmp, ctx->size_B);
61 memmove(ctx->in_block, ctx->in_block + ctx->size_B, ctx->blocksize_B
63 memcpy(ctx->in_block + ctx->blocksize_B - ctx->size_B, block, ctx->size_B);
66 void bcal_cfb_B_decNext(void *block, bcal_cfb_B_ctx_t *ctx)
68 uint8_t tmp[ctx->blocksize_B];
69 uint8_t xblock[ctx->size_B];
70 memcpy(xblock, block, ctx->size_B);
71 memcpy(tmp, ctx->in_block, ctx->blocksize_B);
72 bcal_cipher_enc(tmp, &(ctx->cctx));
73 memxor(block, tmp, ctx->size_B);
74 memmove(ctx->in_block, ctx->in_block + ctx->size_B, ctx->blocksize_B
76 memcpy(ctx->in_block + ctx->blocksize_B - ctx->size_B, xblock, ctx->size_B);
79 void bcal_cfb_B_encMsg(const void *iv, void *msg, uint16_t msg_blocks,
80 bcal_cfb_B_ctx_t *ctx)
82 bcal_cfb_B_loadIV(iv, ctx);
83 while (msg_blocks--) {
84 bcal_cfb_B_encNext(msg, ctx);
85 msg = (uint8_t*) msg + ctx->size_B;
89 void bcal_cfb_B_decMsg(const void *iv, void *msg, uint16_t msg_blocks,
90 bcal_cfb_B_ctx_t *ctx)
92 bcal_cfb_B_loadIV(iv, ctx);
93 while (msg_blocks--) {
94 bcal_cfb_B_decNext(msg, ctx);
95 msg = (uint8_t*) msg + ctx->size_B;