net.siisise.security.mac.MacCBC Maven / Gradle / Ivy
/*
* Copyright 2023 okome.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.siisise.security.mac;
import net.siisise.lang.Bin;
import net.siisise.security.block.Block;
/**
* ハッシュ用に出力を外したCBC
*/
public class MacCBC {
private final Block block;
private long[] vector;
int blen;
int vl;
public MacCBC(Block block) {
this.block = block;
blen = (block.getBlockLength() + 7) / 8;
vl = blen / 8;
vector = new long[vl];
// m = new PacketA();
}
/**
* ブロック単位
* @param src メッセージ
* @param offset 位置
* @param length サイズ(ブロックサイズの整数倍)
*/
void update(byte[] src, int offset, int length) {
int last = offset + length;
while (offset + blen <= last) {
Bin.xorl(vector, src, offset, vl);
vector = block.encrypt(vector, 0);
offset += blen;
}
}
/**
* 結果用
* @return vector
*/
public byte[] vector() {
return Bin.ltob(vector);
}
}