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;
024import java.util.regex.Pattern;
025
026/**
027 * <p><b>InetAddress</b> validation and conversion routines (<code>java.net.InetAddress</code>).</p>
028 *
029 * <p>This class provides methods to validate a candidate IP address.
030 *
031 * <p>
032 * This class is a Singleton; you can retrieve the instance via the {@link #getInstance()} method.
033 * </p>
034 *
035 * @since 1.4
036 */
037public class InetAddressValidator implements Serializable {
038
039    private static final int MAX_BYTE = 128;
040
041    private static final int IPV4_MAX_OCTET_VALUE = 255;
042
043    private static final int MAX_UNSIGNED_SHORT = 0xffff;
044
045    private static final int BASE_16 = 16;
046
047    private static final long serialVersionUID = -919201640201914789L;
048
049    private static final String IPV4_REGEX =
050            "^(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})$";
051
052    // Max number of hex groups (separated by :) in an IPV6 address
053    private static final int IPV6_MAX_HEX_GROUPS = 8;
054
055    // Max hex digits in each IPv6 group
056    private static final int IPV6_MAX_HEX_DIGITS_PER_GROUP = 4;
057
058    /**
059     * Singleton instance of this class.
060     */
061    private static final InetAddressValidator VALIDATOR = new InetAddressValidator();
062
063    private static final Pattern DIGITS_PATTERN = Pattern.compile("\\d{1,3}");
064
065    private static final Pattern ID_CHECK_PATTERN = Pattern.compile("[^\\s/%]+");
066    /**
067     * Returns the singleton instance of this validator.
068     * @return the singleton instance of this validator
069     */
070    public static InetAddressValidator getInstance() {
071        return VALIDATOR;
072    }
073
074    /** IPv4 RegexValidator */
075    private final RegexValidator ipv4Validator = new RegexValidator(IPV4_REGEX);
076
077    /**
078     * Checks if the specified string is a valid IPv4 or IPv6 address.
079     * @param inetAddress the string to validate
080     * @return true if the string validates as an IP address
081     */
082    public boolean isValid(final String inetAddress) {
083        return isValidInet4Address(inetAddress) || isValidInet6Address(inetAddress);
084    }
085
086    /**
087     * Validates an IPv4 address. Returns true if valid.
088     * @param inet4Address the IPv4 address to validate
089     * @return true if the argument contains a valid IPv4 address
090     */
091    public boolean isValidInet4Address(final String inet4Address) {
092        // verify that address conforms to generic IPv4 format
093        final String[] groups = ipv4Validator.match(inet4Address);
094
095        if (groups == null) {
096            return false;
097        }
098
099        // verify that address subgroups are legal
100        for (final String ipSegment : groups) {
101            if (ipSegment == null || ipSegment.isEmpty()) {
102                return false;
103            }
104
105            int iIpSegment = 0;
106
107            try {
108                iIpSegment = Integer.parseInt(ipSegment);
109            } catch (final NumberFormatException e) {
110                return false;
111            }
112
113            if (iIpSegment > IPV4_MAX_OCTET_VALUE) {
114                return false;
115            }
116
117            if (ipSegment.length() > 1 && ipSegment.startsWith("0")) {
118                return false;
119            }
120
121        }
122
123        return true;
124    }
125
126    /**
127     * Validates an IPv6 address. Returns true if valid.
128     * @param inet6Address the IPv6 address to validate
129     * @return true if the argument contains a valid IPv6 address
130     *
131     * @since 1.4.1
132     */
133    public boolean isValidInet6Address(String inet6Address) {
134        String[] parts;
135        // remove prefix size. This will appear after the zone id (if any)
136        parts = inet6Address.split("/", -1);
137        if (parts.length > 2) {
138            return false; // can only have one prefix specifier
139        }
140        if (parts.length == 2) {
141            if (!DIGITS_PATTERN.matcher(parts[1]).matches()) {
142                return false; // not a valid number
143            }
144            final int bits = Integer.parseInt(parts[1]); // cannot fail because of RE check
145            if (bits < 0 || bits > MAX_BYTE) {
146                return false; // out of range
147            }
148        }
149        // remove zone-id
150        parts = parts[0].split("%", -1);
151        if (parts.length > 2) {
152            return false;
153        }
154        // The id syntax is implementation independent, but it presumably cannot allow:
155        // whitespace, '/' or '%'
156        if (parts.length == 2 && !ID_CHECK_PATTERN.matcher(parts[1]).matches()) {
157            return false; // invalid id
158        }
159        inet6Address = parts[0];
160        final boolean containsCompressedZeroes = inet6Address.contains("::");
161        if (containsCompressedZeroes && inet6Address.indexOf("::") != inet6Address.lastIndexOf("::")) {
162            return false;
163        }
164        if (inet6Address.startsWith(":") && !inet6Address.startsWith("::")
165                || inet6Address.endsWith(":") && !inet6Address.endsWith("::")) {
166            return false;
167        }
168        String[] octets = inet6Address.split(":");
169        if (containsCompressedZeroes) {
170            final List<String> octetList = new ArrayList<>(Arrays.asList(octets));
171            if (inet6Address.endsWith("::")) {
172                // String.split() drops ending empty segments
173                octetList.add("");
174            } else if (inet6Address.startsWith("::") && !octetList.isEmpty()) {
175                octetList.remove(0);
176            }
177            octets = octetList.toArray(new String[0]);
178        }
179        if (octets.length > IPV6_MAX_HEX_GROUPS) {
180            return false;
181        }
182        int validOctets = 0;
183        int emptyOctets = 0; // consecutive empty chunks
184        for (int index = 0; index < octets.length; index++) {
185            final String octet = octets[index];
186            if (octet.isEmpty()) {
187                emptyOctets++;
188                if (emptyOctets > 1) {
189                    return false;
190                }
191            } else {
192                emptyOctets = 0;
193                // Is last chunk an IPv4 address?
194                if (index == octets.length - 1 && octet.contains(".")) {
195                    if (!isValidInet4Address(octet)) {
196                        return false;
197                    }
198                    validOctets += 2;
199                    continue;
200                }
201                if (octet.length() > IPV6_MAX_HEX_DIGITS_PER_GROUP) {
202                    return false;
203                }
204                int octetInt = 0;
205                try {
206                    octetInt = Integer.parseInt(octet, BASE_16);
207                } catch (final NumberFormatException e) {
208                    return false;
209                }
210                if (octetInt < 0 || octetInt > MAX_UNSIGNED_SHORT) {
211                    return false;
212                }
213            }
214            validOctets++;
215        }
216        if (validOctets > IPV6_MAX_HEX_GROUPS || validOctets < IPV6_MAX_HEX_GROUPS && !containsCompressedZeroes) {
217            return false;
218        }
219        return true;
220    }
221}