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