org.bermuda.cartilage.core.PacketEncoder.java Source code

Introduction

Here is the source code for org.bermuda.cartilage.core.PacketEncoder.java

Source

/**
 * Copyright (c) 2014 Samuel Hammersley - Gonsalves, Cartilage
 *
 * 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 org.bermuda.cartilage.core;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;

import java.math.BigInteger;

/**
 * Encrypts a packet with using the famous RSA algorithm (cryptosystem)
 * @author Cartilage
 */
public class PacketEncoder extends ChannelOutboundHandlerAdapter {

    @Override
    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
        ByteBuf buf = ctx.alloc().buffer(2);
        byte[] data = new BigInteger((String) msg).modPow(Stream.getRSAExponent(), Stream.getRSAModulus())
                .toByteArray();
        buf.writeBytes(data);
        ctx.write(buf, promise);
    }
}