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 */
017
018package org.apache.commons.validator.routines;
019
020import java.io.Serializable;
021import java.util.ArrayList;
022import java.util.Arrays;
023import java.util.List;
024
025/**
026 * <p><b>InetAddress</b> validation and conversion routines (<code>java.net.InetAddress</code>).</p>
027 *
028 * <p>This class provides methods to validate a candidate IP address.
029 *
030 * <p>
031 * This class is a Singleton; you can retrieve the instance via the {@link #getInstance()} method.
032 * </p>
033 *
034 * @version $Revision$
035 * @since Validator 1.4
036 */
037public class InetAddressValidator implements Serializable {
038
039    private static final int IPV4_MAX_OCTET_VALUE = 255;
040
041    private static final int MAX_UNSIGNED_SHORT = 0xffff;
042
043    private static final int BASE_16 = 16;
044
045    private static final long serialVersionUID = -919201640201914789L;
046
047    private static final String IPV4_REGEX =
048            "^(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})$";
049
050    // Max number of hex groups (separated by :) in an IPV6 address
051    private static final int IPV6_MAX_HEX_GROUPS = 8;
052
053    // Max hex digits in each IPv6 group
054    private static final int IPV6_MAX_HEX_DIGITS_PER_GROUP = 4;
055
056    /**
057     * Singleton instance of this class.
058     */
059    private static final InetAddressValidator VALIDATOR = new InetAddressValidator();
060
061    /** IPv4 RegexValidator */
062    private final RegexValidator ipv4Validator = new RegexValidator(IPV4_REGEX);
063
064    /**
065     * Returns the singleton instance of this validator.
066     * @return the singleton instance of this validator
067     */
068    public static InetAddressValidator getInstance() {
069        return VALIDATOR;
070    }
071
072    /**
073     * Checks if the specified string is a valid IP address.
074     * @param inetAddress the string to validate
075     * @return true if the string validates as an IP address
076     */
077    public boolean isValid(String inetAddress) {
078        return isValidInet4Address(inetAddress) || isValidInet6Address(inetAddress);
079    }
080
081    /**
082     * Validates an IPv4 address. Returns true if valid.
083     * @param inet4Address the IPv4 address to validate
084     * @return true if the argument contains a valid IPv4 address
085     */
086    public boolean isValidInet4Address(String inet4Address) {
087        // verify that address conforms to generic IPv4 format
088        String[] groups = ipv4Validator.match(inet4Address);
089
090        if (groups == null) {
091            return false;
092        }
093
094        // verify that address subgroups are legal
095        for (String ipSegment : groups) {
096            if (ipSegment == null || ipSegment.length() == 0) {
097                return false;
098            }
099
100            int iIpSegment = 0;
101
102            try {
103                iIpSegment = Integer.parseInt(ipSegment);
104            } catch(NumberFormatException e) {
105                return false;
106            }
107
108            if (iIpSegment > IPV4_MAX_OCTET_VALUE) {
109                return false;
110            }
111
112            if (ipSegment.length() > 1 && ipSegment.startsWith("0")) {
113                return false;
114            }
115
116        }
117
118        return true;
119    }
120
121    /**
122     * Validates an IPv6 address. Returns true if valid.
123     * @param inet6Address the IPv6 address to validate
124     * @return true if the argument contains a valid IPv6 address
125     * 
126     * @since 1.4.1
127     */
128    public boolean isValidInet6Address(String inet6Address) {
129        String[] parts;
130        // remove prefix size. This will appear after the zone id (if any)
131        parts = inet6Address.split("/", -1);
132        if (parts.length > 2) {
133            return false; // can only have one prefix specifier
134        }
135        if (parts.length == 2) {
136            if (parts[1].matches("\\d{1,3}")) { // Need to eliminate signs
137                int bits = Integer.parseInt(parts[1]); // cannot fail because of RE check
138                if (bits < 0 || bits > 128) {
139                    return false; // out of range
140                }
141            } else {
142                return false; // not a valid number
143            }
144        }
145        // remove zone-id
146        parts = parts[0].split("%", -1);
147        if (parts.length > 2) {
148            return false;
149        } else if (parts.length == 2){
150            // The id syntax is implemenatation independent, but it presumably cannot allow:
151            // whitespace, '/' or '%'
152            if (!parts[1].matches("[^\\s/%]+")) {
153                return false; // invalid id
154            }
155        }
156        inet6Address = parts[0];
157        boolean containsCompressedZeroes = inet6Address.contains("::");
158        if (containsCompressedZeroes && (inet6Address.indexOf("::") != inet6Address.lastIndexOf("::"))) {
159            return false;
160        }
161        if ((inet6Address.startsWith(":") && !inet6Address.startsWith("::"))
162                || (inet6Address.endsWith(":") && !inet6Address.endsWith("::"))) {
163            return false;
164        }
165        String[] octets = inet6Address.split(":");
166        if (containsCompressedZeroes) {
167            List<String> octetList = new ArrayList<String>(Arrays.asList(octets));
168            if (inet6Address.endsWith("::")) {
169                // String.split() drops ending empty segments
170                octetList.add("");
171            } else if (inet6Address.startsWith("::") && !octetList.isEmpty()) {
172                octetList.remove(0);
173            }
174            octets = octetList.toArray(new String[octetList.size()]);
175        }
176        if (octets.length > IPV6_MAX_HEX_GROUPS) {
177            return false;
178        }
179        int validOctets = 0;
180        int emptyOctets = 0; // consecutive empty chunks
181        for (int index = 0; index < octets.length; index++) {
182            String octet = octets[index];
183            if (octet.length() == 0) {
184                emptyOctets++;
185                if (emptyOctets > 1) {
186                    return false;
187                }
188            } else {
189                emptyOctets = 0;
190                // Is last chunk an IPv4 address?
191                if (index == octets.length - 1 && octet.contains(".")) {
192                    if (!isValidInet4Address(octet)) {
193                        return false;
194                    }
195                    validOctets += 2;
196                    continue;
197                }
198                if (octet.length() > IPV6_MAX_HEX_DIGITS_PER_GROUP) {
199                    return false;
200                }
201                int octetInt = 0;
202                try {
203                    octetInt = Integer.parseInt(octet, BASE_16);
204                } catch (NumberFormatException e) {
205                    return false;
206                }
207                if (octetInt < 0 || octetInt > MAX_UNSIGNED_SHORT) {
208                    return false;
209                }
210            }
211            validOctets++;
212        }
213        if (validOctets > IPV6_MAX_HEX_GROUPS || (validOctets < IPV6_MAX_HEX_GROUPS && !containsCompressedZeroes)) {
214            return false;
215        }
216        return true;
217    }
218}