Andrea Campanella | e408440 | 2017-12-15 15:27:31 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2017-present Open Networking Foundation |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.onosproject.t3.impl; |
| 18 | |
| 19 | import java.math.BigInteger; |
| 20 | import java.net.InetAddress; |
| 21 | import java.net.UnknownHostException; |
| 22 | |
| 23 | /** |
| 24 | * Utility class to test if an Ip is in a given subnet. |
| 25 | */ |
| 26 | public class Subnet { |
| 27 | private final int bytesSubnetCount; |
| 28 | private final BigInteger bigMask; |
| 29 | private final BigInteger bigSubnetMasked; |
| 30 | |
| 31 | /** |
| 32 | * Constructor for use via format "192.168.0.0/24" or "2001:db8:85a3:880:0:0:0:0/57". |
| 33 | * @param subnetAddress the address |
| 34 | * @param bits the mask |
| 35 | */ |
| 36 | public Subnet(InetAddress subnetAddress, int bits) { |
| 37 | bytesSubnetCount = subnetAddress.getAddress().length; // 4 or 16 |
| 38 | bigMask = BigInteger.valueOf(-1).shiftLeft(bytesSubnetCount * 8 - bits); // mask = -1 << 32 - bits |
| 39 | bigSubnetMasked = new BigInteger(subnetAddress.getAddress()).and(bigMask); |
| 40 | } |
| 41 | |
| 42 | /** |
| 43 | * Constructor for use via format "192.168.0.0/255.255.255.0" or single address. |
| 44 | * @param subnetAddress the address |
| 45 | * @param mask the mask |
| 46 | */ |
| 47 | public Subnet(InetAddress subnetAddress, InetAddress mask) { |
| 48 | bytesSubnetCount = subnetAddress.getAddress().length; |
| 49 | // no mask given case is handled here. |
| 50 | bigMask = null == mask ? BigInteger.valueOf(-1) : new BigInteger(mask.getAddress()); |
| 51 | bigSubnetMasked = new BigInteger(subnetAddress.getAddress()).and(bigMask); |
| 52 | } |
| 53 | |
| 54 | /** |
| 55 | * Subnet factory method. |
| 56 | * |
| 57 | * @param subnetMask format: "192.168.0.0/24" or "192.168.0.0/255.255.255.0" |
| 58 | * or single address or "2001:db8:85a3:880:0:0:0:0/57" |
| 59 | * @return a new instance |
| 60 | * @throws UnknownHostException thrown if unsupported subnet mask. |
| 61 | */ |
| 62 | public static Subnet createInstance(String subnetMask) |
| 63 | throws UnknownHostException { |
| 64 | final String[] stringArr = subnetMask.split("/"); |
| 65 | if (2 > stringArr.length) { |
| 66 | return new Subnet(InetAddress.getByName(stringArr[0]), (InetAddress) null); |
| 67 | } else if (stringArr[1].contains(".") || stringArr[1].contains(":")) { |
| 68 | return new Subnet(InetAddress.getByName(stringArr[0]), InetAddress.getByName(stringArr[1])); |
| 69 | } else { |
| 70 | return new Subnet(InetAddress.getByName(stringArr[0]), Integer.parseInt(stringArr[1])); |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Tests if the address is in the given subnet. |
| 76 | * @param address the address to test. |
| 77 | * @return true if inside the subnet |
| 78 | */ |
| 79 | public boolean isInSubnet(InetAddress address) { |
| 80 | byte[] bytesAddress = address.getAddress(); |
| 81 | if (this.bytesSubnetCount != bytesAddress.length) { |
| 82 | return false; |
| 83 | } |
| 84 | BigInteger bigAddress = new BigInteger(bytesAddress); |
| 85 | return bigAddress.and(this.bigMask).equals(this.bigSubnetMasked); |
| 86 | } |
| 87 | |
| 88 | @Override |
| 89 | public final boolean equals(Object obj) { |
| 90 | if (!(obj instanceof Subnet)) { |
| 91 | return false; |
| 92 | } |
| 93 | final Subnet other = (Subnet) obj; |
| 94 | return bigSubnetMasked.equals(other.bigSubnetMasked) && |
| 95 | bigMask.equals(other.bigMask) && |
| 96 | bytesSubnetCount == other.bytesSubnetCount; |
| 97 | } |
| 98 | |
| 99 | @Override |
| 100 | public final int hashCode() { |
| 101 | return bytesSubnetCount; |
| 102 | } |
| 103 | |
| 104 | @Override |
| 105 | public String toString() { |
| 106 | final StringBuilder buf = new StringBuilder(); |
| 107 | bigInteger2IpString(buf, bigSubnetMasked, bytesSubnetCount); |
| 108 | buf.append('/'); |
| 109 | bigInteger2IpString(buf, bigMask, bytesSubnetCount); |
| 110 | return buf.toString(); |
| 111 | } |
| 112 | |
| 113 | private void bigInteger2IpString(StringBuilder buf, BigInteger bigInteger, int displayBytes) { |
| 114 | boolean isIPv4 = 4 == displayBytes; |
| 115 | byte[] bytes = bigInteger.toByteArray(); |
| 116 | int diffLen = displayBytes - bytes.length; |
| 117 | byte fillByte = 0 > (int) bytes[0] ? (byte) 0xFF : (byte) 0x00; |
| 118 | |
| 119 | int integer; |
| 120 | for (int i = 0; i < displayBytes; i++) { |
| 121 | if (0 < i && !isIPv4 && i % 2 == 0) { |
| 122 | buf.append(':'); |
| 123 | } else if (0 < i && isIPv4) { |
| 124 | buf.append('.'); |
| 125 | } |
| 126 | integer = 0xFF & (i < diffLen ? fillByte : bytes[i - diffLen]); |
| 127 | if (!isIPv4 && 0x10 > integer) { |
| 128 | buf.append('0'); |
| 129 | } |
| 130 | buf.append(isIPv4 ? integer : Integer.toHexString(integer)); |
| 131 | } |
| 132 | } |
| 133 | } |