X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=bcal-cbc.c;fp=bcal-cbc.c;h=16d27a1f73bb9f17317392fdd0e65dda5dd3b9a8;hb=3f2f2071c47e2e424af71cc85697f3eb26c24277;hp=0000000000000000000000000000000000000000;hpb=33a28395461ecd0c1c7820f59e180f8f2ca9216f;p=arm-crypto-lib.git

diff --git a/bcal-cbc.c b/bcal-cbc.c
new file mode 100644
index 0000000..16d27a1
--- /dev/null
+++ b/bcal-cbc.c
@@ -0,0 +1,84 @@
+/* bcal-cbc.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-cbc.h"
+#include "bcal-basic.h"
+#include "memxor.h"
+
+uint8_t bcal_cbc_init(const bcdesc_t* desc, const void* key, uint16_t keysize_b, bcal_cbc_ctx_t* ctx){
+	ctx->desc = (bcdesc_t*)desc;
+	ctx->blocksize_B = (bcal_cipher_getBlocksize_b(desc)+7)/8;
+	ctx->prev_block = malloc(ctx->blocksize_B);
+
+	if(ctx->prev_block==NULL){
+		return 0x11;
+	}
+	return bcal_cipher_init(desc, key, keysize_b, &(ctx->cctx));
+}
+
+void bcal_cbc_free(bcal_cbc_ctx_t* ctx){
+	bcal_cipher_free(&(ctx->cctx));
+	free(ctx->prev_block);
+}
+
+
+void bcal_cbc_loadIV(const void* iv, bcal_cbc_ctx_t* ctx){
+	if(iv){
+		memcpy(ctx->prev_block, iv, ctx->blocksize_B);
+	}
+}
+
+void bcal_cbc_encNext(void* block, bcal_cbc_ctx_t* ctx){
+	memxor(block, ctx->prev_block, ctx->blocksize_B);
+	bcal_cipher_enc(block, &(ctx->cctx));
+	memcpy(ctx->prev_block, block, ctx->blocksize_B);
+}
+
+void bcal_cbc_decNext(void* block, bcal_cbc_ctx_t* ctx){
+	uint8_t tmp[ctx->blocksize_B];
+	memcpy(tmp, block, ctx->blocksize_B);
+	bcal_cipher_dec(block, &(ctx->cctx));
+	memxor(block, ctx->prev_block, ctx->blocksize_B);
+	memcpy(ctx->prev_block, tmp, ctx->blocksize_B);
+}
+void bcal_cbc_decRand(void* block, const void* prev_block, bcal_cbc_ctx_t* ctx){
+	bcal_cipher_dec(block, &(ctx->cctx));
+	memxor(block, prev_block, ctx->blocksize_B);
+}
+
+void bcal_cbc_encMsg(const void* iv, void* msg, uint16_t msg_blocks, bcal_cbc_ctx_t* ctx){
+	bcal_cbc_loadIV(iv, ctx);
+	while(msg_blocks--){
+		bcal_cbc_encNext(msg, ctx);
+		msg = (uint8_t*)msg + ctx->blocksize_B;
+	}
+}
+
+void bcal_cbc_decMsg(const void* iv, void* msg, uint16_t msg_blocks, bcal_cbc_ctx_t* ctx){
+	msg=(uint8_t*)msg + (msg_blocks-1)*ctx->blocksize_B;
+	while(msg_blocks > 1){
+		bcal_cbc_decRand(msg, (uint8_t*)msg-ctx->blocksize_B, ctx);
+		msg_blocks -= 1;
+		msg=(uint8_t*)msg-ctx->blocksize_B;
+	}
+	bcal_cbc_decRand(msg, iv, ctx);
+}
+