org.jboss.netty.util.NetUtil Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of netty Show documentation
Show all versions of netty Show documentation
The Netty project is an effort to provide an asynchronous event-driven
network application framework and tools for rapid development of
maintainable high performance and high scalability protocol servers and
clients. In other words, Netty is a NIO client server framework which
enables quick and easy development of network applications such as protocol
servers and clients. It greatly simplifies and streamlines network
programming such as TCP and UDP socket server.
/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package org.jboss.netty.util;
import java.util.ArrayList;
import java.util.StringTokenizer;
/**
* A class that holds a number of network-related constants.
*
* This class borrowed some of its methods from a modified fork of the
* Inet6Util class which was part of Apache Harmony.
*/
public final class NetUtil {
/**
* Creates an byte[] based on an ipAddressString. No error handling is
* performed here.
*/
public static byte[] createByteArrayFromIpAddressString(
String ipAddressString) {
if (isValidIpV4Address(ipAddressString)) {
StringTokenizer tokenizer = new StringTokenizer(ipAddressString,
".");
String token;
int tempInt;
byte[] byteAddress = new byte[4];
for (int i = 0; i < 4; i++) {
token = tokenizer.nextToken();
tempInt = Integer.parseInt(token);
byteAddress[i] = (byte) tempInt;
}
return byteAddress;
}
if (isValidIpV6Address(ipAddressString)) {
if (ipAddressString.charAt(0) == '[') {
ipAddressString = ipAddressString.substring(1, ipAddressString
.length() - 1);
}
StringTokenizer tokenizer = new StringTokenizer(ipAddressString, ":.",
true);
ArrayList hexStrings = new ArrayList();
ArrayList decStrings = new ArrayList();
String token = "";
String prevToken = "";
int doubleColonIndex = -1; // If a double colon exists, we need to
// insert 0s.
// Go through the tokens, including the seperators ':' and '.'
// When we hit a : or . the previous token will be added to either
// the hex list or decimal list. In the case where we hit a ::
// we will save the index of the hexStrings so we can add zeros
// in to fill out the string
while (tokenizer.hasMoreTokens()) {
prevToken = token;
token = tokenizer.nextToken();
if (":".equals(token)) {
if (":".equals(prevToken)) {
doubleColonIndex = hexStrings.size();
} else if (prevToken.length() > 0) {
hexStrings.add(prevToken);
}
} else if (".".equals(token)) {
decStrings.add(prevToken);
}
}
if (":".equals(prevToken)) {
if (":".equals(token)) {
doubleColonIndex = hexStrings.size();
} else {
hexStrings.add(token);
}
} else if (".".equals(prevToken)) {
decStrings.add(token);
}
// figure out how many hexStrings we should have
// also check if it is a IPv4 address
int hexStringsLength = 8;
// If we have an IPv4 address tagged on at the end, subtract
// 4 bytes, or 2 hex words from the total
if (!decStrings.isEmpty()) {
hexStringsLength -= 2;
}
// if we hit a double Colon add the appropriate hex strings
if (doubleColonIndex != -1) {
int numberToInsert = hexStringsLength - hexStrings.size();
for (int i = 0; i < numberToInsert; i++) {
hexStrings.add(doubleColonIndex, "0");
}
}
byte[] ipByteArray = new byte[16];
// Finally convert these strings to bytes...
for (int i = 0; i < hexStrings.size(); i++) {
convertToBytes(hexStrings.get(i), ipByteArray, i * 2);
}
// Now if there are any decimal values, we know where they go...
for (int i = 0; i < decStrings.size(); i++) {
ipByteArray[i + 12] = (byte) (Integer.parseInt(decStrings
.get(i)) & 255);
}
return ipByteArray;
}
return null;
}
/**
* Converts a 4 character hex word into a 2 byte word equivalent
*/
private static void convertToBytes(String hexWord, byte[] ipByteArray,
int byteIndex) {
int hexWordLength = hexWord.length();
int hexWordIndex = 0;
ipByteArray[byteIndex] = 0;
ipByteArray[byteIndex + 1] = 0;
int charValue;
// high order 4 bits of first byte
if (hexWordLength > 3) {
charValue = getIntValue(hexWord.charAt(hexWordIndex++));
ipByteArray[byteIndex] |= charValue << 4;
}
// low order 4 bits of the first byte
if (hexWordLength > 2) {
charValue = getIntValue(hexWord.charAt(hexWordIndex++));
ipByteArray[byteIndex] |= charValue;
}
// high order 4 bits of second byte
if (hexWordLength > 1) {
charValue = getIntValue(hexWord.charAt(hexWordIndex++));
ipByteArray[byteIndex + 1] |= charValue << 4;
}
// low order 4 bits of the first byte
charValue = getIntValue(hexWord.charAt(hexWordIndex));
ipByteArray[byteIndex + 1] |= charValue & 15;
}
static int getIntValue(char c) {
switch (c) {
case '0':
return 0;
case '1':
return 1;
case '2':
return 2;
case '3':
return 3;
case '4':
return 4;
case '5':
return 5;
case '6':
return 6;
case '7':
return 7;
case '8':
return 8;
case '9':
return 9;
}
c = Character.toLowerCase(c);
switch (c) {
case 'a':
return 10;
case 'b':
return 11;
case 'c':
return 12;
case 'd':
return 13;
case 'e':
return 14;
case 'f':
return 15;
}
return 0;
}
public static boolean isValidIpV6Address(String ipAddress) {
int length = ipAddress.length();
boolean doubleColon = false;
int numberOfColons = 0;
int numberOfPeriods = 0;
int numberOfPercent = 0;
StringBuilder word = new StringBuilder();
char c = 0;
char prevChar;
int offset = 0; // offset for [] ip addresses
if (length < 2) {
return false;
}
for (int i = 0; i < length; i++) {
prevChar = c;
c = ipAddress.charAt(i);
switch (c) {
// case for an open bracket [x:x:x:...x]
case '[':
if (i != 0) {
return false; // must be first character
}
if (ipAddress.charAt(length - 1) != ']') {
return false; // must have a close ]
}
offset = 1;
if (length < 4) {
return false;
}
break;
// case for a closed bracket at end of IP [x:x:x:...x]
case ']':
if (i != length - 1) {
return false; // must be last charcter
}
if (ipAddress.charAt(0) != '[') {
return false; // must have a open [
}
break;
// case for the last 32-bits represented as IPv4 x:x:x:x:x:x:d.d.d.d
case '.':
numberOfPeriods++;
if (numberOfPeriods > 3) {
return false;
}
if (!isValidIp4Word(word.toString())) {
return false;
}
if (numberOfColons != 6 && !doubleColon) {
return false;
}
// a special case ::1:2:3:4:5:d.d.d.d allows 7 colons with an
// IPv4 ending, otherwise 7 :'s is bad
if (numberOfColons == 7 && ipAddress.charAt(offset) != ':'
&& ipAddress.charAt(1 + offset) != ':') {
return false;
}
word.delete(0, word.length());
break;
case ':':
// FIX "IP6 mechanism syntax #ip6-bad1"
// An IPV6 address cannot start with a single ":".
// Either it can starti with "::" or with a number.
if (i == offset && (ipAddress.length() <= i || ipAddress.charAt(i + 1) != ':')) {
return false;
}
// END FIX "IP6 mechanism syntax #ip6-bad1"
numberOfColons++;
if (numberOfColons > 7) {
return false;
}
if (numberOfPeriods > 0) {
return false;
}
if (prevChar == ':') {
if (doubleColon) {
return false;
}
doubleColon = true;
}
word.delete(0, word.length());
break;
case '%':
if (numberOfColons == 0) {
return false;
}
numberOfPercent++;
// validate that the stuff after the % is valid
if (i + 1 >= length) {
// in this case the percent is there but no number is
// available
return false;
}
try {
Integer.parseInt(ipAddress.substring(i + 1));
} catch (NumberFormatException e) {
// right now we just support an integer after the % so if
// this is not
// what is there then return
return false;
}
break;
default:
if (numberOfPercent == 0) {
if (word != null && word.length() > 3) {
return false;
}
if (!isValidHexChar(c)) {
return false;
}
}
word.append(c);
}
}
// Check if we have an IPv4 ending
if (numberOfPeriods > 0) {
// There is a test case with 7 colons and valid ipv4 this should resolve it
if (numberOfPeriods != 3 || !(isValidIp4Word(word.toString()) && numberOfColons < 7)) {
return false;
}
} else {
// If we're at then end and we haven't had 7 colons then there is a
// problem unless we encountered a doubleColon
if (numberOfColons != 7 && !doubleColon) {
return false;
}
// If we have an empty word at the end, it means we ended in either
// a : or a .
// If we did not end in :: then this is invalid
if (numberOfPercent == 0) {
if (word.length() == 0 && ipAddress.charAt(length - 1 - offset) == ':'
&& ipAddress.charAt(length - 2 - offset) != ':') {
return false;
}
}
}
return true;
}
public static boolean isValidIp4Word(String word) {
char c;
if (word.length() < 1 || word.length() > 3) {
return false;
}
for (int i = 0; i < word.length(); i++) {
c = word.charAt(i);
if (!(c >= '0' && c <= '9')) {
return false;
}
}
if (Integer.parseInt(word) > 255) {
return false;
}
return true;
}
static boolean isValidHexChar(char c) {
return c >= '0' && c <= '9' || c >= 'A' && c <= 'F'
|| c >= 'a' && c <= 'f';
}
/**
* Takes a string and parses it to see if it is a valid IPV4 address.
*
* @return true, if the string represents an IPV4 address in dotted
* notation, false otherwise
*/
public static boolean isValidIpV4Address(String value) {
int periods = 0;
int i;
int length = value.length();
if (length > 15) {
return false;
}
char c;
StringBuilder word = new StringBuilder();
for (i = 0; i < length; i++) {
c = value.charAt(i);
if (c == '.') {
periods++;
if (periods > 3) {
return false;
}
if (word.length() == 0) {
return false;
}
if (Integer.parseInt(word.toString()) > 255) {
return false;
}
word.delete(0, word.length());
} else if (!Character.isDigit(c)) {
return false;
} else {
if (word.length() > 2) {
return false;
}
word.append(c);
}
}
if (word.length() == 0 || Integer.parseInt(word.toString()) > 255) {
return false;
}
if (periods != 3) {
return false;
}
return true;
}
/**
* A constructor to stop this class being constructed.
*/
private NetUtil() {
// Unused
}
}