001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.openstreetmap.josm.data.validation.routines;
018
019import java.util.ArrayList;
020import java.util.Arrays;
021import java.util.List;
022
023/**
024 * <p><b>InetAddress</b> validation and conversion routines (<code>java.net.InetAddress</code>).</p>
025 *
026 * <p>This class provides methods to validate a candidate IP address.
027 *
028 * <p>
029 * This class is a Singleton; you can retrieve the instance via the {@link #getInstance()} method.
030 * </p>
031 *
032 * @version $Revision: 1741724 $
033 * @since Validator 1.4
034 */
035public class InetAddressValidator extends AbstractValidator {
036
037    private static final int IPV4_MAX_OCTET_VALUE = 255;
038
039    private static final int MAX_UNSIGNED_SHORT = 0xffff;
040
041    private static final int BASE_16 = 16;
042
043    private static final String IPV4_REGEX =
044            "^(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})$";
045
046    // Max number of hex groups (separated by :) in an IPV6 address
047    private static final int IPV6_MAX_HEX_GROUPS = 8;
048
049    // Max hex digits in each IPv6 group
050    private static final int IPV6_MAX_HEX_DIGITS_PER_GROUP = 4;
051
052    /**
053     * Singleton instance of this class.
054     */
055    private static final InetAddressValidator VALIDATOR = new InetAddressValidator();
056
057    /** IPv4 RegexValidator */
058    private final RegexValidator ipv4Validator = new RegexValidator(IPV4_REGEX);
059
060    /**
061     * Returns the singleton instance of this validator.
062     * @return the singleton instance of this validator
063     */
064    public static InetAddressValidator getInstance() {
065        return VALIDATOR;
066    }
067
068    /**
069     * Checks if the specified string is a valid IP address.
070     * @param inetAddress the string to validate
071     * @return true if the string validates as an IP address
072     */
073    @Override
074    public boolean isValid(String inetAddress) {
075        return isValidInet4Address(inetAddress) || isValidInet6Address(inetAddress);
076    }
077
078    @Override
079    public String getValidatorName() {
080        return null;
081    }
082
083    /**
084     * Validates an IPv4 address. Returns true if valid.
085     * @param inet4Address the IPv4 address to validate
086     * @return true if the argument contains a valid IPv4 address
087     */
088    public boolean isValidInet4Address(String inet4Address) {
089        // verify that address conforms to generic IPv4 format
090        String[] groups = ipv4Validator.match(inet4Address);
091
092        if (groups == null) {
093            return false;
094        }
095
096        // verify that address subgroups are legal
097        for (String ipSegment : groups) {
098            if (ipSegment == null || ipSegment.isEmpty()) {
099                return false;
100            }
101
102            int iIpSegment = 0;
103
104            try {
105                iIpSegment = Integer.parseInt(ipSegment);
106            } catch (NumberFormatException e) {
107                return false;
108            }
109
110            if (iIpSegment > IPV4_MAX_OCTET_VALUE) {
111                return false;
112            }
113
114            if (ipSegment.length() > 1 && ipSegment.startsWith("0")) {
115                return false;
116            }
117
118        }
119
120        return true;
121    }
122
123    /**
124     * Validates an IPv6 address. Returns true if valid.
125     * @param inet6Address the IPv6 address to validate
126     * @return true if the argument contains a valid IPv6 address
127     *
128     * @since 1.4.1
129     */
130    public boolean isValidInet6Address(String inet6Address) {
131        boolean containsCompressedZeroes = inet6Address.contains("::");
132        if (containsCompressedZeroes && (inet6Address.indexOf("::") != inet6Address.lastIndexOf("::"))) {
133            return false;
134        }
135        if ((inet6Address.startsWith(":") && !inet6Address.startsWith("::"))
136                || (inet6Address.endsWith(":") && !inet6Address.endsWith("::"))) {
137            return false;
138        }
139        String[] octets = inet6Address.split(":");
140        if (containsCompressedZeroes) {
141            List<String> octetList = new ArrayList<>(Arrays.asList(octets));
142            if (inet6Address.endsWith("::")) {
143                // String.split() drops ending empty segments
144                octetList.add("");
145            } else if (inet6Address.startsWith("::") && !octetList.isEmpty()) {
146                octetList.remove(0);
147            }
148            octets = octetList.toArray(new String[octetList.size()]);
149        }
150        if (octets.length > IPV6_MAX_HEX_GROUPS) {
151            return false;
152        }
153        int validOctets = 0;
154        int emptyOctets = 0;
155        for (int index = 0; index < octets.length; index++) {
156            String octet = octets[index];
157            if (octet.length() == 0) {
158                emptyOctets++;
159                if (emptyOctets > 1) {
160                    return false;
161                }
162            } else {
163                emptyOctets = 0;
164                if (octet.contains(".")) { // contains is Java 1.5+
165                    if (!inet6Address.endsWith(octet)) {
166                        return false;
167                    }
168                    if (index > octets.length - 1 || index > 6) { // CHECKSTYLE IGNORE MagicNumber
169                        // IPV4 occupies last two octets
170                        return false;
171                    }
172                    if (!isValidInet4Address(octet)) {
173                        return false;
174                    }
175                    validOctets += 2;
176                    continue;
177                }
178                if (octet.length() > IPV6_MAX_HEX_DIGITS_PER_GROUP) {
179                    return false;
180                }
181                int octetInt = 0;
182                try {
183                    octetInt = Integer.valueOf(octet, BASE_16).intValue();
184                } catch (NumberFormatException e) {
185                    return false;
186                }
187                if (octetInt < 0 || octetInt > MAX_UNSIGNED_SHORT) {
188                    return false;
189                }
190            }
191            validOctets++;
192        }
193        if (validOctets < IPV6_MAX_HEX_GROUPS && !containsCompressedZeroes) {
194            return false;
195        }
196        return true;
197    }
198}