BaseIpAddressOption.java

/*
 * Copyright 2009-2014 Jagornet Technologies, LLC.  All Rights Reserved.
 *
 * This software is the proprietary information of Jagornet Technologies, LLC. 
 * Use is subject to license terms.
 *
 */

/*
 *   This file BaseIpAddressOption.java is part of Jagornet DHCP.
 *
 *   Jagornet DHCP 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.
 *
 *   Jagornet DHCP 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 Jagornet DHCP.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
package com.jagornet.dhcp.option.base;

import java.io.IOException;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.nio.ByteBuffer;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.jagornet.dhcp.util.Util;
import com.jagornet.dhcp.xml.IpAddressOptionType;
import com.jagornet.dhcp.xml.Operator;
import com.jagornet.dhcp.xml.OptionExpression;

/**
 * Title: BaseIpAddressOption
 * Description: The abstract base class for ip address DHCP options.
 * 
 * @author A. Gregory Rabil
 */
public abstract class BaseIpAddressOption extends BaseDhcpOption
{
	private static Logger log = LoggerFactory.getLogger(BaseIpAddressOption.class);

	protected String ipAddress;
	
	public BaseIpAddressOption()
	{
		this(null);
	}
	
	public BaseIpAddressOption(IpAddressOptionType ipAddressOption)
	{
		super();
		if (ipAddressOption != null) {
			ipAddress = ipAddressOption.getIpAddress();
		}
	}
	
    public String getIpAddress() {
		return ipAddress;
	}

	public void setIpAddress(String ipAddress) {
		this.ipAddress = ipAddress;
	}

	/* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.Encodable#encode()
     */
    public ByteBuffer encode() throws IOException
    {
    	ByteBuffer buf = super.encodeCodeAndLength();
        if (ipAddress != null) {
        	InetAddress inetAddr = null;
        	if (!super.isV4()) {
        		inetAddr = Inet6Address.getByName(ipAddress);
        	}
        	else {
        		inetAddr = Inet4Address.getByName(ipAddress);
        	}
            buf.put(inetAddr.getAddress());
        }
        return (ByteBuffer) buf.flip();
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.Decodable#decode(java.nio.ByteBuffer)
     */
    public void decode(ByteBuffer buf) throws IOException
    {
    	int len = super.decodeLength(buf);
    	if ((len > 0) && (len <= buf.remaining())) {
    		if (!super.isV4()) {
    			ipAddress = decodeIpAddress(buf);
    		}
    		else {
    			ipAddress = decodeIpV4Address(buf);
    		}
        }
    }
    
    /**
     * Convert an IPv6 address received from the wire to a string.
     * 
     * @param buf the ByteBuffer containing the IPv6 address to be decoded from the wire
     * @return the string representation of the IPv6 address
     * @throws IOException
     */
    public static String decodeIpAddress(ByteBuffer buf) throws IOException
    {
        // it has to be hex from the wire, right?
        byte[] b = new byte[16];
        buf.get(b);
        InetAddress inetAddr = InetAddress.getByAddress(b);
        return inetAddr.getHostAddress();
    }
    
    /**
     * Convert an IPv4 address received from the wire to a string.
     * 
     * @param buf the ByteBuffer containing the IPv4 address to be decoded from the wire
     * @return the string representation of the IPv4 address
     * @throws IOException
     */
    public static String decodeIpV4Address(ByteBuffer buf) throws IOException
    {
        // it has to be hex from the wire, right?
        byte[] b = new byte[4];
        buf.get(b);
        InetAddress inetAddr = InetAddress.getByAddress(b);
        return inetAddr.getHostAddress();
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.DhcpOption#getLength()
     */
    public int getLength()
    {
    	if (!super.isV4())
    		return 16;		// 128-bit IPv6 address
    	else
    		return 4;		// 32-bit IPv4 address
    }

    /* (non-Javadoc)
     * @see com.jagornet.dhcpv6.option.DhcpComparableOption#matches(com.jagornet.dhcp.xml.OptionExpression)
     */
    public boolean matches(OptionExpression expression)
    {
        if (expression == null)
            return false;
        if (expression.getCode() != this.getCode())
            return false;
        if (ipAddress == null)
        	return false;
        
        IpAddressOptionType exprOption = expression.getIpAddressOption();
        if (exprOption != null) {
        	String exprIpAddress = exprOption.getIpAddress();
            Operator.Enum op = expression.getOperator();
            if (op.equals(Operator.EQUALS)) {
            	return ipAddress.equals(exprIpAddress);
            }
            else if (op.equals(Operator.STARTS_WITH)) {
            	return ipAddress.startsWith(exprIpAddress);
            }
            else if (op.equals(Operator.ENDS_WITH)) {
            	return ipAddress.endsWith(exprIpAddress);
            }
            else if (op.equals(Operator.CONTAINS)) {
            	return ipAddress.contains(exprIpAddress);
            }
            else if (op.equals(Operator.REG_EXP)) {
            	return ipAddress.matches(exprIpAddress);
            }
            else {
            	log.warn("Unsupported expression operator: " + op);
            }
        }
        
        return false;
    }

    /* (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    public String toString()
    {
        StringBuilder sb = new StringBuilder(Util.LINE_SEPARATOR);
        sb.append(super.getName());
        sb.append(": ipAddress=");
        sb.append(ipAddress);
        return sb.toString();
    }

}