radiuspacket.java

TinyRadius is a simple, small and fast Java Radius library capable of sending and receiving Radius

/**
 * $Id: RadiusPacket.java,v 1.11 2006/02/20 23:44:49 wuttke Exp $
 * Created on 07.04.2005
 * Released under the LGPL
 * @author Matthias Wuttke
 * @version $Revision: 1.11 $
 */
package org.tinyradius.packet;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import org.tinyradius.attribute.RadiusAttribute;
import org.tinyradius.attribute.VendorSpecificAttribute;
import org.tinyradius.dictionary.AttributeType;
import org.tinyradius.dictionary.DefaultDictionary;
import org.tinyradius.dictionary.Dictionary;
import org.tinyradius.util.RadiusException;
import org.tinyradius.util.RadiusUtil;

/**
 * This class represents a Radius packet. Subclasses provide convenience methods
 * for special packet types.
 */
public class RadiusPacket {
	
    /**
     * Packet type codes.
     */
	public static final int ACCESS_REQUEST      = 1;
	public static final int ACCESS_ACCEPT       = 2;
	public static final int ACCESS_REJECT       = 3;
	public static final int ACCOUNTING_REQUEST  = 4;
	public static final int ACCOUNTING_RESPONSE = 5;
	public static final int ACCOUNTING_STATUS   = 6;
	public static final int PASSWORD_REQUEST    = 7;
	public static final int PASSWORD_ACCEPT     = 8;
	public static final int PASSWORD_REJECT     = 9;
	public static final int ACCOUNTING_MESSAGE  = 10;
	public static final int ACCESS_CHALLENGE    = 11;
	public static final int STATUS_SERVER       = 12;
	public static final int STATUS_CLIENT       = 13;
	public static final int DISCONNECT_REQUEST  = 40;	// RFC 2882
	public static final int DISCONNECT_ACK      = 41;
	public static final int DISCONNECT_NAK      = 42;
	public static final int COA_REQUEST         = 43;
	public static final int COA_ACK             = 44;
	public static final int COA_NAK             = 45;
	public static final int STATUS_REQUEST      = 46;
	public static final int STATUS_ACCEPT       = 47;
	public static final int STATUS_REJECT       = 48;
	public static final int RESERVED            = 255;

	/**
	 * Maximum packet length.
	 */
	public static final int MAX_PACKET_LENGTH = 4096;
	
	/**
	 * Packet header length.
	 */
    public static final int RADIUS_HEADER_LENGTH  = 20;

	/**
	 * Builds a Radius packet without attributes. Retrieves
	 * the next packet identifier.
	 * @param type packet type 
	 */
	public RadiusPacket(final int type) {
	    this(type, getNextPacketIdentifier(), new ArrayList());
	}
	
	/**
	 * Builds a Radius packet with the given type and identifier
	 * and without attributes.
	 * @param type packet type
	 * @param identifier packet identifier
	 */
	public RadiusPacket(final int type, final int identifier) {
	    this(type, identifier, new ArrayList());
	}
	
	/**
	 * Builds a Radius packet with the given type, identifier and
	 * attributes. 
	 * @param type packet type
	 * @param identifier packet identifier
	 * @param attributes list of RadiusAttribute objects
	 */
	public RadiusPacket(final int type, final int identifier, final List attributes) {
		setPacketType(type);
	    setPacketIdentifier(identifier);
	    setAttributes(attributes);
	}
	
	/**
	 * Builds an empty Radius packet.
	 */
	public RadiusPacket() {
	}
	
	/**
	 * Returns the packet identifier for this Radius packet.
	 * @return packet identifier
	 */
	public int getPacketIdentifier() {
		return packetIdentifier;
	}
	
	/**
	 * Sets the packet identifier for this Radius packet.
	 * @param identifier packet identifier, 0-255
	 */
	public void setPacketIdentifier(int identifier) {
		if (identifier < 0 || identifier > 255)
			throw new IllegalArgumentException("packet identifier out of bounds");
		this.packetIdentifier = identifier;
	}
	
	/**
	 * Returns the type of this Radius packet.
	 * @return packet type
	 */
	public int getPacketType() {
		return packetType;
	}
	
	/**
	 * Returns the type name of this Radius packet.
	 * @return name
	 */
	public String getPacketTypeName() {
		switch (getPacketType()) {
		case ACCESS_REQUEST: return "Access-Request";
		case ACCESS_ACCEPT: return "Access-Accept";
		case ACCESS_REJECT: return "Access-Reject";
		case ACCOUNTING_REQUEST : return "Accounting-Request";
		case ACCOUNTING_RESPONSE: return "Accounting-Response";
		case ACCOUNTING_STATUS: return "Accounting-Status";
		case PASSWORD_REQUEST: return "Password-Request";
		case PASSWORD_ACCEPT: return "Password-Accept";
		case PASSWORD_REJECT: return "Password-Reject";
		case ACCOUNTING_MESSAGE: return "Accounting-Message";
		case ACCESS_CHALLENGE: return "Access-Challenge";
		case STATUS_SERVER: return "Status-Server";
		case STATUS_CLIENT: return "Status-Client";
		// RFC 2882
		case DISCONNECT_REQUEST: return "Disconnect-Request";	
		case DISCONNECT_ACK: return "Disconnect-ACK";
		case DISCONNECT_NAK: return "Disconnect-NAK";
		case COA_REQUEST: return "CoA-Request";
		case COA_ACK: return "CoA-ACK";
		case COA_NAK: return "CoA-NAK";
		case STATUS_REQUEST: return "Status-Request";
		case STATUS_ACCEPT: return "Status-Accept";
		case STATUS_REJECT: return "Status-Reject";
		case RESERVED: return "Reserved";
		default: return "Unknown (" + getPacketType() + ")";
		}
	}
	
	/**
	 * Sets the type of this Radius packet.
	 * @param type packet type, 0-255
	 */
	public void setPacketType(int type) {
		if (type < 1 || type > 255)
			throw new IllegalArgumentException("packet type out of bounds");
		this.packetType = type;
	}
	
	/**
	 * Sets the list of attributes for this Radius packet.
	 * @param attributes list of RadiusAttribute objects
	 */
	public void setAttributes(List attributes) {
		if (attributes == null)
			throw new NullPointerException("attributes list is null");
		
		for (Iterator i = attributes.iterator(); i.hasNext();) {
			Object element = i.next();
			if (!(element instanceof RadiusAttribute))
				throw new IllegalArgumentException("attribute not an instance of RadiusAttribute");
		}
		
		this.attributes = attributes;
	}
	
	/**
	 * Adds a Radius attribute to this packet. Can also be used
	 * to add Vendor-Specific sub-attributes. If a attribute with
	 * a vendor code != -1 is passed in, a VendorSpecificAttribute
	 * is created for the sub-attribute.
	 * @param attribute RadiusAttribute object
	 */
	public void addAttribute(RadiusAttribute attribute) {
		if (attribute == null)
			throw new NullPointerException("attribute is null");
		attribute.setDictionary(getDictionary());
		if (attribute.getVendorId() == -1)
			this.attributes.add(attribute);
		else {
			VendorSpecificAttribute vsa = new VendorSpecificAttribute(attribute.getVendorId());
			vsa.addSubAttribute(attribute);
			this.attributes.add(vsa);
		}
	}
	
	/**
	 * Adds a Radius attribute to this packet.
	 * Uses AttributeTypes to lookup the type code and converts
	 * the value.
	 * Can also be used to add sub-attributes.
	 * @param typeName name of the attribute, for example "NAS-Ip-Address"
	 * @param value value of the attribute, for example "127.0.0.1"
	 * @throws IllegalArgumentException if type name is unknown
	 */
	public void addAttribute(String typeName, String value) {
		if (typeName == null || typeName.length() == 0)
			throw new IllegalArgumentException("type name is empty");
		if (value == null || value.length() == 0)
			throw new IllegalArgumentException("value is empty");
		
		AttributeType type = dictionary.getAttributeTypeByName(typeName);
		if (type == null)
			throw new IllegalArgumentException("unknown attribute type '" + typeName + "'");

		RadiusAttribute attribute = RadiusAttribute.createRadiusAttribute(getDictionary(), type.getVendorId(), type.getTypeCode());
		attribute.setAttributeValue(value);
		addAttribute(attribute);
	}
	
	/**
	 * Removes the specified attribute from this packet.
	 * @param attribute RadiusAttribute to remove
	 */
	public void removeAttribute(RadiusAttribute attribute) {
		if (attribute.getVendorId() == -1) {
			if (!this.attributes.remove(attribute))
				throw new IllegalArgumentException("no such attribute");
		} else {
			// remove Vendor-Specific sub-attribute
			List vsas = getVendorAttributes(attribute.getVendorId());
			for (Iterator i = vsas.iterator(); i.hasNext();) {
				VendorSpecificAttribute vsa = (VendorSpecificAttribute)i.next();
				List sas = vsa.getSubAttributes(); 
				if (sas.contains(attribute)) {
					vsa.removeSubAttribute(attribute);
					if (sas.size() == 1)
						// removed the last sub-attribute
						// --> remove the whole Vendor-Specific attribute
						removeAttribute(vsa);
				}
			}		
		}
	}
	
	/**
	 * Removes all attributes from this packet which have got
	 * the specified type.
	 * @param type attribute type to remove
	 */
	public void removeAttributes(int type) {
		if (type < 1 || type > 255)
			throw new IllegalArgumentException("attribute type out of bounds");
		
		Iterator i = attributes.iterator();
		while (i.hasNext()) {
			RadiusAttribute attribute = (RadiusAttribute)i.next();
			if (attribute.getAttributeType() == type)
				i.remove();
		}
	}
	
	/**
	 * Removes the last occurence of the attribute of the given
	 * type from the packet.
	 * @param type attribute type code
	 */
	public void removeLastAttribute(int type) {
		List attrs = getAttributes(type);
		if (attrs == null || attrs.size() == 0)
			return;
		
		RadiusAttribute lastAttribute =
			(RadiusAttribute)attrs.get(attrs.size() - 1);
		removeAttribute(lastAttribute);
	}
	
	/**
	 * Removes all sub-attributes of the given vendor and
	 * type.
	 * @param vendorId vendor ID
	 * @param typeCode attribute type code
	 */
	public void removeAttributes(int vendorId, int typeCode) {
		if (vendorId == -1) {
			removeAttributes(typeCode);
			return;
		}
		
		List vsas = getVendorAttributes(vendorId);
		for (Iterator i = vsas.iterator(); i.hasNext();) {
			VendorSpecificAttribute vsa = (VendorSpecificAttribute)i.next();
			
			List sas = vsa.getSubAttributes();
			for (Iterator j = sas.iterator(); j.hasNext();) {
				RadiusAttribute attr = (RadiusAttribute)j.next();
				if (attr.getAttributeType() == typeCode &&
					attr.getVendorId() == vendorId)
					j.remove();
			}
			if (sas.size() == 0)
				// removed the last sub-attribute
				// --> remove the whole Vendor-Specific attribute
				removeAttribute(vsa);
		}
	}
	
	/**
	 * Returns all attributes of this packet of the given type.
	 * Returns an empty list if there are no such attributes.
	 * @param attributeType type of attributes to get 
	 * @return list of RadiusAttribute objects, does not return null
	 */
	public List getAttributes(int attributeType) {