/*
* Password Management Servlets (PWM)
* http://www.pwm-project.org
*
* Copyright (c) 2006-2009 Novell, Inc.
* Copyright (c) 2009-2017 The PWM Project
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package password.pwm.util;
import java.net.Inet6Address;
import java.net.UnknownHostException;
public class IPMatcher
{
/** Network to match */
private byte[] network;
/** Network mask */
private byte[] netmask;
/**
* Construct an IPMatcher that will test for the given IP specification
*
* @param ipSpec
* IP specification (full or partial address, network/netmask,
* network/cidr)
* @throws IPMatcherException
* if there is an error parsing the specification (i.e. it is
* somehow malformed)
*/
public IPMatcher(final String ipSpec) throws IPMatcherException
{
// Boil all specs down to network + mask
String ipPart = ipSpec;
final String[] parts = ipSpec.split("/");
if (parts[0].indexOf(':') >= 0)
{ // looks like IPv6
try
{
network = Inet6Address.getByName(parts[0]).getAddress();
} catch (UnknownHostException e) {
throw new IPMatcherException(
"Malformed IP range specification " + ipSpec, e);
}
netmask = new byte[16];
switch(parts.length)
{
case 2: // CIDR notation: calculate the mask
final int maskBits;
try {
maskBits = Integer.parseInt(parts[1]);
} catch (NumberFormatException nfe) {
throw new IPMatcherException(
"Malformed IP range specification " + ipSpec, nfe);
}
if (maskBits < 0 || maskBits > 128) {
throw new IPMatcherException("Mask bits out of range 0-128 "
+ ipSpec);
}
final int maskBytes = maskBits/8;
for (int i = 0; i < maskBytes; i++) {
netmask[i] = (byte) 0Xff;
}
netmask[maskBytes] = (byte) ((byte) 0Xff << 8-(maskBits % 8)); // FIXME test!
for (int i = maskBytes+1; i < (128/8); i++) {
netmask[i] = 0;
}
break;
case 1: // No explicit mask: fill the mask with 1s
for (int i = 0; i < netmask.length; i++) {
netmask[i] = (byte) 0Xff;
}
break;
default:
throw new IPMatcherException("Malformed IP range specification "
+ ipSpec);
}
} else { // assume IPv4
// Allow partial IP
boolean mustHave4 = false;
network = new byte[4];
netmask = new byte[4];
switch (parts.length)
{
case 2:
// Some kind of slash notation -- we'll need a full network IP
ipPart = parts[0];
mustHave4 = true;
final String[] maskParts = parts[1].split("\\.");
if (maskParts.length == 1)
{
// CIDR slash notation
final int x;
try
{
x = Integer.parseInt(maskParts[0]);
} catch (NumberFormatException nfe) {
throw new IPMatcherException(
"Malformed IP range specification " + ipSpec, nfe);
}
if (x < 0 || x > 32)
{
throw new IPMatcherException();
}
final int fullMask = -1 << (32 - x);
netmask[0] = (byte) ((fullMask & 0xFF000000) >>> 24);
netmask[1] = (byte) ((fullMask & 0x00FF0000) >>> 16);
netmask[2] = (byte) ((fullMask & 0x0000FF00) >>> 8);
netmask[3] = (byte) (fullMask & 0x000000FF);
ipToBytes(ipPart, network, mustHave4);
} else {
// full subnet specified
ipToBytes(parts[0],network,true);
ipToBytes(parts[1], netmask, true);
}
break;
case 1:
// Get IP
for (int i = 0; i < netmask.length; i++) {
netmask[i] = -1;
}
final int partCount = ipToBytes(ipPart, network, mustHave4);
// If partial IP, set mask for remaining bytes
for (int i = 3; i >= partCount; i--)
{
netmask[i] = 0;
}
break;
default:
throw new IPMatcherException("Malformed IP range specification "
+ ipSpec);
}
network = ip4ToIp6(network);
netmask = ip4MaskToIp6(netmask);
}
}
/**
* Fill out a given four-byte array with the IPv4 address specified in the
* given String
*
* @param ip
* IPv4 address as a dot-delimited String
* @param bytes
* 4-byte array to fill out
* @param mustHave4
* if true, will require that the given IP string specify all
* four bytes
* @return the number of actual IP bytes found in the given IP address
* String
* @throws IPMatcherException
* if there is a problem parsing the IP string -- e.g. number
* outside of range 0-255, too many numbers, less than 4 numbers
* if {@code mustHave4} is true
*/
private static int ipToBytes(final String ip, final byte[] bytes, final boolean mustHave4)
throws IPMatcherException
{
final String[] parts = ip.split("\\.");
if (parts.length > 4 || mustHave4 && parts.length != 4)
{
throw new IPMatcherException("Malformed IP specification " + ip);
}
try
{
for (int i = 0; i < parts.length; i++)
{
final int p = Integer.parseInt(parts[i]);
if (p < 0 || p > 255)
{
throw new IPMatcherException("Malformed IP specification "
+ ip);
}
bytes[i] = (byte) (p < 128 ? p : p - 256);
}
} catch (NumberFormatException nfe) {
throw new IPMatcherException("Malformed IP specification " + ip,
nfe);
}
return parts.length;
}
/**
* Determine whether the given full IP falls within the range this
* {@code IPMatcher} was initialized with.
*
* @param ipIn
* IP address as dot-delimited String
* @return {@code true} if the IP matches the range of this
* {@code IPMatcher}; {@code false} otherwise
* @throws IPMatcherException
* if the IP passed in cannot be parsed correctly (i.e. is
* malformed)
*/
public boolean match(final String ipIn) throws IPMatcherException
{
byte[] candidate;
if (ipIn.indexOf(':') < 0) {
candidate = new byte[4];
ipToBytes(ipIn, candidate, true);
candidate = ip4ToIp6(candidate);
} else {
try {
candidate = Inet6Address.getByName(ipIn).getAddress();
} catch (UnknownHostException e) {
throw new IPMatcherException("Malformed IPv6 address ", e);
}
}
for (int i = 0; i < netmask.length; i++)
{
if ((candidate[i] & netmask[i]) != (network[i] & netmask[i]))
{
return false;
}
}
return true;
}
/**
* Convert an IPv4 address to an IPv6 IPv4-compatible address.
* @param ip4 an IPv4 address
* @return the corresponding IPv6 address
* @throws IllegalArgumentException if ip4 is not exactly four octets long.
*/
private static byte[] ip4ToIp6(final byte[] ip4)
{
if (ip4.length != 4) {
throw new IllegalArgumentException("IPv4 address must be four octets");
}
final byte[] ip6 = new byte[16];
for (int i = 0; i < 16-4; i++) {
ip6[i] = 0;
}
for (int i = 0; i < 4; i++) {
ip6[12 + i] = ip4[i];
}
return ip6;
}
/**
* Convert an IPv4 mask to the equivalent IPv6 mask.
* @param ip4 an IPv4 mask
* @return the corresponding IPv6 mask
* @throws IllegalArgumentException if ip4 is not exactly four octets long.
*/
private static byte[] ip4MaskToIp6(final byte[] ip4)
{
if (ip4.length != 4) {
throw new IllegalArgumentException("IPv4 mask must be four octets");
}
final byte[] ip6 = new byte[16];
for (int i = 0; i < 16-4; i++) {
ip6[i] = (byte) 0Xff;
}
for (int i = 0; i < 4; i++) {
ip6[12 + i] = ip4[i];
}
return ip6;
}
public static class IPMatcherException extends Exception {
public IPMatcherException()
{
super();
}
public IPMatcherException(final String message)
{
super(message);
}
public IPMatcherException(final Throwable cause)
{
super(cause);
}
public IPMatcherException(final String message, final Throwable cause)
{
super(message, cause);
}
}
}