/*
* @(#)file NetMaskImpl.java
* @(#)author Sun Microsystems, Inc.
* @(#)version 1.6
* @(#)date 05/08/26
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*/
package com.sun.jmx.snmp.IPAcl;
import java.util.Vector;
import java.util.Enumeration;
import java.io.Serializable;
import java.net.UnknownHostException;
import java.net.InetAddress;
import java.security.Principal;
import java.security.acl.Group;
import com.sun.jmx.trace.Trace;
/**
* This class is used to represent a subnet mask (a group of hosts matching the same
* IP mask).
*
* @see java.security.acl.Group
* @version 4.5 02/03/00
* @author Sun Microsystems, Inc
*/
class NetMaskImpl extends PrincipalImpl implements Group, Serializable {
protected byte[] subnet = null;
protected int prefix = -1;
/**
* Constructs an empty group.
* @exception UnknownHostException Not implemented
*/
public NetMaskImpl () throws UnknownHostException {
}
private byte[] extractSubNet(byte[] b) {
int addrLength = b.length;
byte[] subnet = null;
if(isDebugOn()) {
debug("extractSubNet","BINARY ARRAY :");
StringBuffer buff = new StringBuffer();
for(int i =0; i < addrLength; i++) {
buff.append((int)(b[i] &0xFF) +":");
}
debug("extractSubNet", buff.toString());
}
// 8 is a byte size. Common to any InetAddress (V4 or V6).
int fullyCoveredByte = prefix / 8;
if(fullyCoveredByte == addrLength) {
if(isDebugOn()) {
debug("extractSubNet"," The mask is the complete address, strange..." + addrLength);
}
subnet = b;
return subnet;
}
if(fullyCoveredByte > addrLength) {
if(isDebugOn()) {
debug("extractSubNet"," The number of covered byte is longer than the address. BUG");
}
throw new IllegalArgumentException("The number of covered byte is longer than the address.");
}
int partialyCoveredIndex = fullyCoveredByte;
if(isDebugOn()) {
debug("extractSubNet"," Partialy covered index : " + partialyCoveredIndex);
}
byte toDeal = b[partialyCoveredIndex];
if(isDebugOn()) {
debug("extractSubNet"," Partialy covered byte : " + toDeal);
}
// 8 is a byte size. Common to any InetAddress (V4 or V6).
int nbbits = prefix % 8;
int subnetSize = 0;
if(nbbits == 0)
subnetSize = partialyCoveredIndex;
else
subnetSize = partialyCoveredIndex + 1;
if(isDebugOn()) {
debug("extractSubNet"," Remains : " + nbbits);
}
byte mask = 0;
for(int i = 0; i < nbbits; i++) {
mask |= (1 << (7 - i));
}
if(isDebugOn()) {
debug("extractSubNet","Mask value" + (int) (mask & 0xFF));
}
byte maskedValue = (byte) ((int)toDeal & (int)mask);
if(isDebugOn()) {
debug("extractSubNet","Masked byte :" + (int) (maskedValue &0xFF));
}
subnet = new byte[subnetSize];
if(isDebugOn()) {
debug("extractSubNet","Resulting subnet : ");
}
for(int i = 0; i < partialyCoveredIndex; i++) {
subnet[i] = b[i];
if(isDebugOn()) {
debug("extractSubNet",(int) (subnet[i] & 0xFF) +":");
}
}
if(nbbits != 0) {
subnet[partialyCoveredIndex] = maskedValue;
if(isDebugOn()) {
debug("extractSubNet"," Last subnet byte : " + (int) (subnet[partialyCoveredIndex] &0xFF));
}
}
return subnet;
}
/**
* Constructs a group using the specified subnet mask.
* THIS ALGORITHM IS V4 and V6 compatible.
*
* @exception UnknownHostException if the subnet mask cann't be built.
*/
public NetMaskImpl (String a, int prefix) throws UnknownHostException {
super(a);
this.prefix = prefix;
subnet = extractSubNet(getAddress().getAddress());
}
/**
* Adds the specified member to the group.
*
* @param p the principal to add to this group.
* @return true if the member was successfully added, false if the
* principal was already a member.
*/
public boolean addMember(Principal p) {
// we don't need to add members because the ip address is a subnet mask
return true;
}
public int hashCode() {
return super.hashCode();
}
/**
* Compares this group to the specified object. Returns true if the object
* passed in matches the group represented.
*
* @param p the object to compare with.
* @return true if the object passed in matches the subnet mask,
* false otherwise.
*/
public boolean equals (Object p) {
if (p instanceof PrincipalImpl || p instanceof NetMaskImpl){
PrincipalImpl received = (PrincipalImpl) p;
InetAddress addr = received.getAddress();
if(isDebugOn()) {
debug("equals","Received Address : " + addr);
}
byte[] recAddr = addr.getAddress();
for(int i = 0; i < subnet.length; i++) {
if(isDebugOn()) {
debug("equals","(recAddr[i]) :" + (recAddr[i] & 0xFF));
debug("equals","(recAddr[i] & subnet[i]) :" +
( (int) (recAddr[i] & (int)subnet[i]) &0xFF) +
"subnet[i] :" + (int) (subnet[i] &0xFF));
}
if((recAddr[i] & subnet[i]) != subnet[i]) {
if(isDebugOn()) {
debug("equals","FALSE");
}
return false;
}
}
if(isDebugOn()) {
debug("equals","TRUE");
}
return true;
} else
return false;
}
/**
* Returns true if the passed principal is a member of the group.
*
* @param p the principal whose membership is to be checked.
* @return true if the principal is a member of this group, false otherwise.
*/
public boolean isMember(Principal p) {
if ((p.hashCode() & super.hashCode()) == p.hashCode()) return true;
else return false;
}
/**
* Returns an enumeration which contains the subnet mask.
*
* @return an enumeration which contains the subnet mask.
*/
public Enumeration members(){
Vector v = new Vector(1);
v.addElement(this);
return v.elements();
}
/**
* Removes the specified member from the group. (Not implemented)
*
* @param p the principal to remove from this group.
* @return allways return true.
*/
public boolean removeMember(Principal p) {
return true;
}
/**
* Prints a string representation of this group.
*
* @return a string representation of this group.
*/
public String toString() {
return ("NetMaskImpl :"+ super.getAddress().toString() + "/" + prefix);
}
// TRACES & DEBUG
//---------------
boolean isTraceOn() {
return Trace.isSelected(Trace.LEVEL_TRACE, Trace.INFO_SNMP);
}
void trace(String clz, String func, String info) {
Trace.send(Trace.LEVEL_TRACE, Trace.INFO_SNMP, clz, func, info);
}
void trace(String func, String info) {
trace(dbgTag, func, info);
}
boolean isDebugOn() {
return Trace.isSelected(Trace.LEVEL_DEBUG, Trace.INFO_SNMP);
}
void debug(String clz, String func, String info) {
Trace.send(Trace.LEVEL_DEBUG, Trace.INFO_SNMP, clz, func, info);
}
void debug(String clz, String func, Throwable exception) {
Trace.send(Trace.LEVEL_DEBUG, Trace.INFO_SNMP, clz, func, exception);
}
void debug(String func, String info) {
debug(dbgTag, func, info);
}
void debug(String func, Throwable exception) {
debug(dbgTag, func, exception);
}
String dbgTag = "NetMaskImpl";
}
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