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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* 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:
*
* https://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 io.netty.util;
import io.netty.util.NetUtilInitializations.NetworkIfaceAndInetAddress;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
import java.util.Collection;
import static io.netty.util.AsciiString.indexOf;
/**
* 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 {
/**
* The {@link Inet4Address} that represents the IPv4 loopback address '127.0.0.1'
*/
public static final Inet4Address LOCALHOST4;
/**
* The {@link Inet6Address} that represents the IPv6 loopback address '::1'
*/
public static final Inet6Address LOCALHOST6;
/**
* The {@link InetAddress} that represents the loopback address. If IPv6 stack is available, it will refer to
* {@link #LOCALHOST6}. Otherwise, {@link #LOCALHOST4}.
*/
public static final InetAddress LOCALHOST;
/**
* The loopback {@link NetworkInterface} of the current machine
*/
public static final NetworkInterface LOOPBACK_IF;
/**
* An unmodifiable Collection of all the interfaces on this machine.
*/
public static final Collection NETWORK_INTERFACES;
/**
* The SOMAXCONN value of the current machine. If failed to get the value, {@code 200} is used as a
* default value for Windows and {@code 128} for others.
*/
public static final int SOMAXCONN;
/**
* This defines how many words (represented as ints) are needed to represent an IPv6 address
*/
private static final int IPV6_WORD_COUNT = 8;
/**
* The maximum number of characters for an IPV6 string with no scope
*/
private static final int IPV6_MAX_CHAR_COUNT = 39;
/**
* Number of bytes needed to represent an IPV6 value
*/
private static final int IPV6_BYTE_COUNT = 16;
/**
* Maximum amount of value adding characters in between IPV6 separators
*/
private static final int IPV6_MAX_CHAR_BETWEEN_SEPARATOR = 4;
/**
* Minimum number of separators that must be present in an IPv6 string
*/
private static final int IPV6_MIN_SEPARATORS = 2;
/**
* Maximum number of separators that must be present in an IPv6 string
*/
private static final int IPV6_MAX_SEPARATORS = 8;
/**
* Maximum amount of value adding characters in between IPV4 separators
*/
private static final int IPV4_MAX_CHAR_BETWEEN_SEPARATOR = 3;
/**
* Number of separators that must be present in an IPv4 string
*/
private static final int IPV4_SEPARATORS = 3;
/**
* {@code true} if IPv4 should be used even if the system supports both IPv4 and IPv6.
*/
private static final boolean IPV4_PREFERRED = SystemPropertyUtil.getBoolean("java.net.preferIPv4Stack", false);
/**
* {@code true} if an IPv6 address should be preferred when a host has both an IPv4 address and an IPv6 address.
*/
private static final boolean IPV6_ADDRESSES_PREFERRED;
/**
* The logger being used by this class
*/
private static final InternalLogger logger = InternalLoggerFactory.getInstance(NetUtil.class);
static {
String prefer = SystemPropertyUtil.get("java.net.preferIPv6Addresses", "false");
if ("true".equalsIgnoreCase(prefer.trim())) {
IPV6_ADDRESSES_PREFERRED = true;
} else {
// Let's just use false in this case as only true is "forcing" ipv6.
IPV6_ADDRESSES_PREFERRED = false;
}
logger.debug("-Djava.net.preferIPv4Stack: {}", IPV4_PREFERRED);
logger.debug("-Djava.net.preferIPv6Addresses: {}", prefer);
NETWORK_INTERFACES = NetUtilInitializations.networkInterfaces();
// Create IPv4 loopback address.
LOCALHOST4 = NetUtilInitializations.createLocalhost4();
// Create IPv6 loopback address.
LOCALHOST6 = NetUtilInitializations.createLocalhost6();
NetworkIfaceAndInetAddress loopback =
NetUtilInitializations.determineLoopback(NETWORK_INTERFACES, LOCALHOST4, LOCALHOST6);
LOOPBACK_IF = loopback.iface();
LOCALHOST = loopback.address();
// As a SecurityManager may prevent reading the somaxconn file we wrap this in a privileged block.
//
// See https://github.com/netty/netty/issues/3680
SOMAXCONN = AccessController.doPrivileged(new SoMaxConnAction());
}
private static final class SoMaxConnAction implements PrivilegedAction {
@Override
public Integer run() {
// Determine the default somaxconn (server socket backlog) value of the platform.
// The known defaults:
// - Windows NT Server 4.0+: 200
// - Linux and Mac OS X: 128
int somaxconn = PlatformDependent.isWindows() ? 200 : 128;
File file = new File("/proc/sys/net/core/somaxconn");
BufferedReader in = null;
try {
// file.exists() may throw a SecurityException if a SecurityManager is used, so execute it in the
// try / catch block.
// See https://github.com/netty/netty/issues/4936
if (file.exists()) {
in = new BufferedReader(new FileReader(file));
somaxconn = Integer.parseInt(in.readLine());
if (logger.isDebugEnabled()) {
logger.debug("{}: {}", file, somaxconn);
}
} else {
// Try to get from sysctl
Integer tmp = null;
if (SystemPropertyUtil.getBoolean("io.netty.net.somaxconn.trySysctl", false)) {
tmp = sysctlGetInt("kern.ipc.somaxconn");
if (tmp == null) {
tmp = sysctlGetInt("kern.ipc.soacceptqueue");
if (tmp != null) {
somaxconn = tmp;
}
} else {
somaxconn = tmp;
}
}
if (tmp == null) {
logger.debug("Failed to get SOMAXCONN from sysctl and file {}. Default: {}", file,
somaxconn);
}
}
} catch (Exception e) {
if (logger.isDebugEnabled()) {
logger.debug("Failed to get SOMAXCONN from sysctl and file {}. Default: {}",
file, somaxconn, e);
}
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e) {
// Ignored.
}
}
}
return somaxconn;
}
}
/**
* This will execute sysctl with the {@code sysctlKey}
* which is expected to return the numeric value for for {@code sysctlKey}.
* @param sysctlKey The key which the return value corresponds to.
* @return The sysctl value for {@code sysctlKey}.
*/
private static Integer sysctlGetInt(String sysctlKey) throws IOException {
Process process = new ProcessBuilder("sysctl", sysctlKey).start();
try {
// Suppress warnings about resource leaks since the buffered reader is closed below
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
try {
String line = br.readLine();
if (line != null && line.startsWith(sysctlKey)) {
for (int i = line.length() - 1; i > sysctlKey.length(); --i) {
if (!Character.isDigit(line.charAt(i))) {
return Integer.valueOf(line.substring(i + 1));
}
}
}
return null;
} finally {
br.close();
}
} finally {
// No need of 'null' check because we're initializing
// the Process instance in first line. Any exception
// raised will directly lead to throwable.
process.destroy();
}
}
/**
* Returns {@code true} if IPv4 should be used even if the system supports both IPv4 and IPv6. Setting this
* property to {@code true} will disable IPv6 support. The default value of this property is {@code false}.
*
* @see Java SE
* networking properties
*/
public static boolean isIpV4StackPreferred() {
return IPV4_PREFERRED;
}
/**
* Returns {@code true} if an IPv6 address should be preferred when a host has both an IPv4 address and an IPv6
* address. The default value of this property is {@code false}.
*
* @see Java SE
* networking properties
*/
public static boolean isIpV6AddressesPreferred() {
return IPV6_ADDRESSES_PREFERRED;
}
/**
* Creates an byte[] based on an ipAddressString. No error handling is performed here.
*/
public static byte[] createByteArrayFromIpAddressString(String ipAddressString) {
if (isValidIpV4Address(ipAddressString)) {
return validIpV4ToBytes(ipAddressString);
}
if (isValidIpV6Address(ipAddressString)) {
if (ipAddressString.charAt(0) == '[') {
ipAddressString = ipAddressString.substring(1, ipAddressString.length() - 1);
}
int percentPos = ipAddressString.indexOf('%');
if (percentPos >= 0) {
ipAddressString = ipAddressString.substring(0, percentPos);
}
return getIPv6ByName(ipAddressString, true);
}
return null;
}
/**
* Creates an {@link InetAddress} based on an ipAddressString or might return null if it can't be parsed.
* No error handling is performed here.
*/
public static InetAddress createInetAddressFromIpAddressString(String ipAddressString) {
if (isValidIpV4Address(ipAddressString)) {
byte[] bytes = validIpV4ToBytes(ipAddressString);
try {
return InetAddress.getByAddress(bytes);
} catch (UnknownHostException e) {
// Should never happen!
throw new IllegalStateException(e);
}
}
if (isValidIpV6Address(ipAddressString)) {
if (ipAddressString.charAt(0) == '[') {
ipAddressString = ipAddressString.substring(1, ipAddressString.length() - 1);
}
int percentPos = ipAddressString.indexOf('%');
if (percentPos >= 0) {
try {
int scopeId = Integer.parseInt(ipAddressString.substring(percentPos + 1));
ipAddressString = ipAddressString.substring(0, percentPos);
byte[] bytes = getIPv6ByName(ipAddressString, true);
if (bytes == null) {
return null;
}
try {
return Inet6Address.getByAddress(null, bytes, scopeId);
} catch (UnknownHostException e) {
// Should never happen!
throw new IllegalStateException(e);
}
} catch (NumberFormatException e) {
return null;
}
}
byte[] bytes = getIPv6ByName(ipAddressString, true);
if (bytes == null) {
return null;
}
try {
return InetAddress.getByAddress(bytes);
} catch (UnknownHostException e) {
// Should never happen!
throw new IllegalStateException(e);
}
}
return null;
}
private static int decimalDigit(String str, int pos) {
return str.charAt(pos) - '0';
}
private static byte ipv4WordToByte(String ip, int from, int toExclusive) {
int ret = decimalDigit(ip, from);
from++;
if (from == toExclusive) {
return (byte) ret;
}
ret = ret * 10 + decimalDigit(ip, from);
from++;
if (from == toExclusive) {
return (byte) ret;
}
return (byte) (ret * 10 + decimalDigit(ip, from));
}
// visible for tests
static byte[] validIpV4ToBytes(String ip) {
int i;
return new byte[] {
ipv4WordToByte(ip, 0, i = ip.indexOf('.', 1)),
ipv4WordToByte(ip, i + 1, i = ip.indexOf('.', i + 2)),
ipv4WordToByte(ip, i + 1, i = ip.indexOf('.', i + 2)),
ipv4WordToByte(ip, i + 1, ip.length())
};
}
/**
* Convert {@link Inet4Address} into {@code int}
*/
public static int ipv4AddressToInt(Inet4Address ipAddress) {
byte[] octets = ipAddress.getAddress();
return (octets[0] & 0xff) << 24 |
(octets[1] & 0xff) << 16 |
(octets[2] & 0xff) << 8 |
octets[3] & 0xff;
}
/**
* Converts a 32-bit integer into an IPv4 address.
*/
public static String intToIpAddress(int i) {
StringBuilder buf = new StringBuilder(15);
buf.append(i >> 24 & 0xff);
buf.append('.');
buf.append(i >> 16 & 0xff);
buf.append('.');
buf.append(i >> 8 & 0xff);
buf.append('.');
buf.append(i & 0xff);
return buf.toString();
}
/**
* Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
*
* @throws IllegalArgumentException
* if {@code length} is not {@code 4} nor {@code 16}
*/
public static String bytesToIpAddress(byte[] bytes) {
return bytesToIpAddress(bytes, 0, bytes.length);
}
/**
* Converts 4-byte or 16-byte data into an IPv4 or IPv6 string respectively.
*
* @throws IllegalArgumentException
* if {@code length} is not {@code 4} nor {@code 16}
*/
public static String bytesToIpAddress(byte[] bytes, int offset, int length) {
switch (length) {
case 4: {
return new StringBuilder(15)
.append(bytes[offset] & 0xff)
.append('.')
.append(bytes[offset + 1] & 0xff)
.append('.')
.append(bytes[offset + 2] & 0xff)
.append('.')
.append(bytes[offset + 3] & 0xff).toString();
}
case 16:
return toAddressString(bytes, offset, false);
default:
throw new IllegalArgumentException("length: " + length + " (expected: 4 or 16)");
}
}
public static boolean isValidIpV6Address(String ip) {
return isValidIpV6Address((CharSequence) ip);
}
public static boolean isValidIpV6Address(CharSequence ip) {
int end = ip.length();
if (end < 2) {
return false;
}
// strip "[]"
int start;
char c = ip.charAt(0);
if (c == '[') {
end--;
if (ip.charAt(end) != ']') {
// must have a close ]
return false;
}
start = 1;
c = ip.charAt(1);
} else {
start = 0;
}
int colons;
int compressBegin;
if (c == ':') {
// an IPv6 address can start with "::" or with a number
if (ip.charAt(start + 1) != ':') {
return false;
}
colons = 2;
compressBegin = start;
start += 2;
} else {
colons = 0;
compressBegin = -1;
}
int wordLen = 0;
loop:
for (int i = start; i < end; i++) {
c = ip.charAt(i);
if (isValidHexChar(c)) {
if (wordLen < 4) {
wordLen++;
continue;
}
return false;
}
switch (c) {
case ':':
if (colons > 7) {
return false;
}
if (ip.charAt(i - 1) == ':') {
if (compressBegin >= 0) {
return false;
}
compressBegin = i - 1;
} else {
wordLen = 0;
}
colons++;
break;
case '.':
// case for the last 32-bits represented as IPv4 x:x:x:x:x:x:d.d.d.d
// check a normal case (6 single colons)
if (compressBegin < 0 && colons != 6 ||
// a special case ::1:2:3:4:5:d.d.d.d allows 7 colons with an
// IPv4 ending, otherwise 7 :'s is bad
(colons == 7 && compressBegin >= start || colons > 7)) {
return false;
}
// Verify this address is of the correct structure to contain an IPv4 address.
// It must be IPv4-Mapped or IPv4-Compatible
// (see https://tools.ietf.org/html/rfc4291#section-2.5.5).
int ipv4Start = i - wordLen;
int j = ipv4Start - 2; // index of character before the previous ':'.
if (isValidIPv4MappedChar(ip.charAt(j))) {
if (!isValidIPv4MappedChar(ip.charAt(j - 1)) ||
!isValidIPv4MappedChar(ip.charAt(j - 2)) ||
!isValidIPv4MappedChar(ip.charAt(j - 3))) {
return false;
}
j -= 5;
}
for (; j >= start; --j) {
char tmpChar = ip.charAt(j);
if (tmpChar != '0' && tmpChar != ':') {
return false;
}
}
// 7 - is minimum IPv4 address length
int ipv4End = indexOf(ip, '%', ipv4Start + 7);
if (ipv4End < 0) {
ipv4End = end;
}
return isValidIpV4Address(ip, ipv4Start, ipv4End);
case '%':
// strip the interface name/index after the percent sign
end = i;
break loop;
default:
return false;
}
}
// normal case without compression
if (compressBegin < 0) {
return colons == 7 && wordLen > 0;
}
return compressBegin + 2 == end ||
// 8 colons is valid only if compression in start or end
wordLen > 0 && (colons < 8 || compressBegin <= start);
}
private static boolean isValidIpV4Word(CharSequence word, int from, int toExclusive) {
int len = toExclusive - from;
char c0, c1, c2;
if (len < 1 || len > 3 || (c0 = word.charAt(from)) < '0') {
return false;
}
if (len == 3) {
return (c1 = word.charAt(from + 1)) >= '0' &&
(c2 = word.charAt(from + 2)) >= '0' &&
(c0 <= '1' && c1 <= '9' && c2 <= '9' ||
c0 == '2' && c1 <= '5' && (c2 <= '5' || c1 < '5' && c2 <= '9'));
}
return c0 <= '9' && (len == 1 || isValidNumericChar(word.charAt(from + 1)));
}
private static boolean isValidHexChar(char c) {
return c >= '0' && c <= '9' || c >= 'A' && c <= 'F' || c >= 'a' && c <= 'f';
}
private static boolean isValidNumericChar(char c) {
return c >= '0' && c <= '9';
}
private static boolean isValidIPv4MappedChar(char c) {
return c == 'f' || c == 'F';
}
private static boolean isValidIPv4MappedSeparators(byte b0, byte b1, boolean mustBeZero) {
// We allow IPv4 Mapped (https://tools.ietf.org/html/rfc4291#section-2.5.5.1)
// and IPv4 compatible (https://tools.ietf.org/html/rfc4291#section-2.5.5.1).
// The IPv4 compatible is deprecated, but it allows parsing of plain IPv4 addressed into IPv6-Mapped addresses.
return b0 == b1 && (b0 == 0 || !mustBeZero && b1 == -1);
}
private static boolean isValidIPv4Mapped(byte[] bytes, int currentIndex, int compressBegin, int compressLength) {
final boolean mustBeZero = compressBegin + compressLength >= 14;
return currentIndex <= 12 && currentIndex >= 2 && (!mustBeZero || compressBegin < 12) &&
isValidIPv4MappedSeparators(bytes[currentIndex - 1], bytes[currentIndex - 2], mustBeZero) &&
PlatformDependent.isZero(bytes, 0, currentIndex - 3);
}
/**
* Takes a {@link CharSequence} 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(CharSequence ip) {
return isValidIpV4Address(ip, 0, ip.length());
}
/**
* Takes a {@link 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 ip) {
return isValidIpV4Address(ip, 0, ip.length());
}
private static boolean isValidIpV4Address(CharSequence ip, int from, int toExcluded) {
return ip instanceof String ? isValidIpV4Address((String) ip, from, toExcluded) :
ip instanceof AsciiString ? isValidIpV4Address((AsciiString) ip, from, toExcluded) :
isValidIpV4Address0(ip, from, toExcluded);
}
@SuppressWarnings("DuplicateBooleanBranch")
private static boolean isValidIpV4Address(String ip, int from, int toExcluded) {
int len = toExcluded - from;
int i;
return len <= 15 && len >= 7 &&
(i = ip.indexOf('.', from + 1)) > 0 && isValidIpV4Word(ip, from, i) &&
(i = ip.indexOf('.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
(i = ip.indexOf('.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
isValidIpV4Word(ip, i + 1, toExcluded);
}
@SuppressWarnings("DuplicateBooleanBranch")
private static boolean isValidIpV4Address(AsciiString ip, int from, int toExcluded) {
int len = toExcluded - from;
int i;
return len <= 15 && len >= 7 &&
(i = ip.indexOf('.', from + 1)) > 0 && isValidIpV4Word(ip, from, i) &&
(i = ip.indexOf('.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
(i = ip.indexOf('.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
isValidIpV4Word(ip, i + 1, toExcluded);
}
@SuppressWarnings("DuplicateBooleanBranch")
private static boolean isValidIpV4Address0(CharSequence ip, int from, int toExcluded) {
int len = toExcluded - from;
int i;
return len <= 15 && len >= 7 &&
(i = indexOf(ip, '.', from + 1)) > 0 && isValidIpV4Word(ip, from, i) &&
(i = indexOf(ip, '.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
(i = indexOf(ip, '.', from = i + 2)) > 0 && isValidIpV4Word(ip, from - 1, i) &&
isValidIpV4Word(ip, i + 1, toExcluded);
}
/**
* Returns the {@link Inet6Address} representation of a {@link CharSequence} IP address.
*
* This method will treat all IPv4 type addresses as "IPv4 mapped" (see {@link #getByName(CharSequence, boolean)})
* @param ip {@link CharSequence} IP address to be converted to a {@link Inet6Address}
* @return {@link Inet6Address} representation of the {@code ip} or {@code null} if not a valid IP address.
*/
public static Inet6Address getByName(CharSequence ip) {
return getByName(ip, true);
}
/**
* Returns the {@link Inet6Address} representation of a {@link CharSequence} IP address.
*
* The {@code ipv4Mapped} parameter specifies how IPv4 addresses should be treated.
* "IPv4 mapped" format as
* defined in rfc 4291 section 2 is supported.
* @param ip {@link CharSequence} IP address to be converted to a {@link Inet6Address}
* @param ipv4Mapped
*
* - {@code true} To allow IPv4 mapped inputs to be translated into {@link Inet6Address}
* - {@code false} Consider IPv4 mapped addresses as invalid.
*
* @return {@link Inet6Address} representation of the {@code ip} or {@code null} if not a valid IP address.
*/
public static Inet6Address getByName(CharSequence ip, boolean ipv4Mapped) {
byte[] bytes = getIPv6ByName(ip, ipv4Mapped);
if (bytes == null) {
return null;
}
try {
return Inet6Address.getByAddress(null, bytes, -1);
} catch (UnknownHostException e) {
throw new RuntimeException(e); // Should never happen
}
}
/**
* Returns the byte array representation of a {@link CharSequence} IP address.
*
* The {@code ipv4Mapped} parameter specifies how IPv4 addresses should be treated.
* "IPv4 mapped" format as
* defined in rfc 4291 section 2 is supported.
* @param ip {@link CharSequence} IP address to be converted to a {@link Inet6Address}
* @param ipv4Mapped
*
* - {@code true} To allow IPv4 mapped inputs to be translated into {@link Inet6Address}
* - {@code false} Consider IPv4 mapped addresses as invalid.
*
* @return byte array representation of the {@code ip} or {@code null} if not a valid IP address.
*/
// visible for test
static byte[] getIPv6ByName(CharSequence ip, boolean ipv4Mapped) {
final byte[] bytes = new byte[IPV6_BYTE_COUNT];
final int ipLength = ip.length();
int compressBegin = 0;
int compressLength = 0;
int currentIndex = 0;
int value = 0;
int begin = -1;
int i = 0;
int ipv6Separators = 0;
int ipv4Separators = 0;
int tmp;
for (; i < ipLength; ++i) {
final char c = ip.charAt(i);
switch (c) {
case ':':
++ipv6Separators;
if (i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv4Separators > 0 || ipv6Separators > IPV6_MAX_SEPARATORS ||
currentIndex + 1 >= bytes.length) {
return null;
}
value <<= (IPV6_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
if (compressLength > 0) {
compressLength -= 2;
}
// The value integer holds at most 4 bytes from right (most significant) to left (least significant).
// The following bit shifting is used to extract and re-order the individual bytes to achieve a
// left (most significant) to right (least significant) ordering.
bytes[currentIndex++] = (byte) (((value & 0xf) << 4) | ((value >> 4) & 0xf));
bytes[currentIndex++] = (byte) ((((value >> 8) & 0xf) << 4) | ((value >> 12) & 0xf));
tmp = i + 1;
if (tmp < ipLength && ip.charAt(tmp) == ':') {
++tmp;
if (compressBegin != 0 || (tmp < ipLength && ip.charAt(tmp) == ':')) {
return null;
}
++ipv6Separators;
compressBegin = currentIndex;
compressLength = bytes.length - compressBegin - 2;
++i;
}
value = 0;
begin = -1;
break;
case '.':
++ipv4Separators;
tmp = i - begin; // tmp is the length of the current segment.
if (tmp > IPV4_MAX_CHAR_BETWEEN_SEPARATOR
|| begin < 0
|| ipv4Separators > IPV4_SEPARATORS
|| (ipv6Separators > 0 && (currentIndex + compressLength < 12))
|| i + 1 >= ipLength
|| currentIndex >= bytes.length
|| ipv4Separators == 1 &&
// We also parse pure IPv4 addresses as IPv4-Mapped for ease of use.
((!ipv4Mapped || currentIndex != 0 && !isValidIPv4Mapped(bytes, currentIndex,
compressBegin, compressLength)) ||
(tmp == 3 && (!isValidNumericChar(ip.charAt(i - 1)) ||
!isValidNumericChar(ip.charAt(i - 2)) ||
!isValidNumericChar(ip.charAt(i - 3))) ||
tmp == 2 && (!isValidNumericChar(ip.charAt(i - 1)) ||
!isValidNumericChar(ip.charAt(i - 2))) ||
tmp == 1 && !isValidNumericChar(ip.charAt(i - 1))))) {
return null;
}
value <<= (IPV4_MAX_CHAR_BETWEEN_SEPARATOR - tmp) << 2;
// The value integer holds at most 3 bytes from right (most significant) to left (least significant).
// The following bit shifting is to restructure the bytes to be left (most significant) to
// right (least significant) while also accounting for each IPv4 digit is base 10.
begin = (value & 0xf) * 100 + ((value >> 4) & 0xf) * 10 + ((value >> 8) & 0xf);
if (begin > 255) {
return null;
}
bytes[currentIndex++] = (byte) begin;
value = 0;
begin = -1;
break;
default:
if (!isValidHexChar(c) || (ipv4Separators > 0 && !isValidNumericChar(c))) {
return null;
}
if (begin < 0) {
begin = i;
} else if (i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR) {
return null;
}
// The value is treated as a sort of array of numbers because we are dealing with
// at most 4 consecutive bytes we can use bit shifting to accomplish this.
// The most significant byte will be encountered first, and reside in the right most
// position of the following integer
value += StringUtil.decodeHexNibble(c) << ((i - begin) << 2);
break;
}
}
final boolean isCompressed = compressBegin > 0;
// Finish up last set of data that was accumulated in the loop (or before the loop)
if (ipv4Separators > 0) {
if (begin > 0 && i - begin > IPV4_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv4Separators != IPV4_SEPARATORS ||
currentIndex >= bytes.length) {
return null;
}
if (!(ipv6Separators == 0 || ipv6Separators >= IPV6_MIN_SEPARATORS &&
(!isCompressed && (ipv6Separators == 6 && ip.charAt(0) != ':') ||
isCompressed && (ipv6Separators < IPV6_MAX_SEPARATORS &&
(ip.charAt(0) != ':' || compressBegin <= 2))))) {
return null;
}
value <<= (IPV4_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
// The value integer holds at most 3 bytes from right (most significant) to left (least significant).
// The following bit shifting is to restructure the bytes to be left (most significant) to
// right (least significant) while also accounting for each IPv4 digit is base 10.
begin = (value & 0xf) * 100 + ((value >> 4) & 0xf) * 10 + ((value >> 8) & 0xf);
if (begin > 255) {
return null;
}
bytes[currentIndex++] = (byte) begin;
} else {
tmp = ipLength - 1;
if (begin > 0 && i - begin > IPV6_MAX_CHAR_BETWEEN_SEPARATOR ||
ipv6Separators < IPV6_MIN_SEPARATORS ||
!isCompressed && (ipv6Separators + 1 != IPV6_MAX_SEPARATORS ||
ip.charAt(0) == ':' || ip.charAt(tmp) == ':') ||
isCompressed && (ipv6Separators > IPV6_MAX_SEPARATORS ||
(ipv6Separators == IPV6_MAX_SEPARATORS &&
(compressBegin <= 2 && ip.charAt(0) != ':' ||
compressBegin >= 14 && ip.charAt(tmp) != ':'))) ||
currentIndex + 1 >= bytes.length ||
begin < 0 && ip.charAt(tmp - 1) != ':' ||
compressBegin > 2 && ip.charAt(0) == ':') {
return null;
}
if (begin >= 0 && i - begin <= IPV6_MAX_CHAR_BETWEEN_SEPARATOR) {
value <<= (IPV6_MAX_CHAR_BETWEEN_SEPARATOR - (i - begin)) << 2;
}
// The value integer holds at most 4 bytes from right (most significant) to left (least significant).
// The following bit shifting is used to extract and re-order the individual bytes to achieve a
// left (most significant) to right (least significant) ordering.
bytes[currentIndex++] = (byte) (((value & 0xf) << 4) | ((value >> 4) & 0xf));
bytes[currentIndex++] = (byte) ((((value >> 8) & 0xf) << 4) | ((value >> 12) & 0xf));
}
if (currentIndex < bytes.length) {
int toBeCopiedLength = currentIndex - compressBegin;
int targetIndex = bytes.length - toBeCopiedLength;
System.arraycopy(bytes, compressBegin, bytes, targetIndex, toBeCopiedLength);
// targetIndex is also the `toIndex` to fill 0
Arrays.fill(bytes, compressBegin, targetIndex, (byte) 0);
}
if (ipv4Separators > 0) {
// We only support IPv4-Mapped addresses [1] because IPv4-Compatible addresses are deprecated [2].
// [1] https://tools.ietf.org/html/rfc4291#section-2.5.5.2
// [2] https://tools.ietf.org/html/rfc4291#section-2.5.5.1
bytes[10] = bytes[11] = (byte) 0xff;
}
return bytes;
}
/**
* Returns the {@link String} representation of an {@link InetSocketAddress}.
*
* The output does not include Scope ID.
* @param addr {@link InetSocketAddress} to be converted to an address string
* @return {@code String} containing the text-formatted IP address
*/
public static String toSocketAddressString(InetSocketAddress addr) {
String port = String.valueOf(addr.getPort());
final StringBuilder sb;
if (addr.isUnresolved()) {
String hostname = getHostname(addr);
sb = newSocketAddressStringBuilder(hostname, port, !isValidIpV6Address(hostname));
} else {
InetAddress address = addr.getAddress();
String hostString = toAddressString(address);
sb = newSocketAddressStringBuilder(hostString, port, address instanceof Inet4Address);
}
return sb.append(':').append(port).toString();
}
/**
* Returns the {@link String} representation of a host port combo.
*/
public static String toSocketAddressString(String host, int port) {
String portStr = String.valueOf(port);
return newSocketAddressStringBuilder(
host, portStr, !isValidIpV6Address(host)).append(':').append(portStr).toString();
}
private static StringBuilder newSocketAddressStringBuilder(String host, String port, boolean ipv4) {
int hostLen = host.length();
if (ipv4) {
// Need to include enough space for hostString:port.
return new StringBuilder(hostLen + 1 + port.length()).append(host);
}
// Need to include enough space for [hostString]:port.
StringBuilder stringBuilder = new StringBuilder(hostLen + 3 + port.length());
if (hostLen > 1 && host.charAt(0) == '[' && host.charAt(hostLen - 1) == ']') {
return stringBuilder.append(host);
}
return stringBuilder.append('[').append(host).append(']');
}
/**
* Returns the {@link String} representation of an {@link InetAddress}.
*
* - Inet4Address results are identical to {@link InetAddress#getHostAddress()}
* - Inet6Address results adhere to
* rfc 5952 section 4
*
*
* The output does not include Scope ID.
* @param ip {@link InetAddress} to be converted to an address string
* @return {@code String} containing the text-formatted IP address
*/
public static String toAddressString(InetAddress ip) {
return toAddressString(ip, false);
}
/**
* Returns the {@link String} representation of an {@link InetAddress}.
*
* - Inet4Address results are identical to {@link InetAddress#getHostAddress()}
* - Inet6Address results adhere to
* rfc 5952 section 4 if
* {@code ipv4Mapped} is false. If {@code ipv4Mapped} is true then "IPv4 mapped" format
* from rfc 4291 section 2 will be supported.
* The compressed result will always obey the compression rules defined in
* rfc 5952 section 4
*
*
* The output does not include Scope ID.
* @param ip {@link InetAddress} to be converted to an address string
* @param ipv4Mapped
*
* - {@code true} to stray from strict rfc 5952 and support the "IPv4 mapped" format
* defined in rfc 4291 section 2 while still
* following the updated guidelines in
* rfc 5952 section 4
* - {@code false} to strictly follow rfc 5952
*
* @return {@code String} containing the text-formatted IP address
*/
public static String toAddressString(InetAddress ip, boolean ipv4Mapped) {
if (ip instanceof Inet4Address) {
return ip.getHostAddress();
}
if (!(ip instanceof Inet6Address)) {
throw new IllegalArgumentException("Unhandled type: " + ip);
}
return toAddressString(ip.getAddress(), 0, ipv4Mapped);
}
private static String toAddressString(byte[] bytes, int offset, boolean ipv4Mapped) {
final int[] words = new int[IPV6_WORD_COUNT];
for (int i = 0; i < words.length; ++i) {
int idx = (i << 1) + offset;
words[i] = ((bytes[idx] & 0xff) << 8) | (bytes[idx + 1] & 0xff);
}
// Find longest run of 0s, tie goes to first found instance
int currentStart = -1;
int currentLength;
int shortestStart = -1;
int shortestLength = 0;
for (int i = 0; i < words.length; ++i) {
if (words[i] == 0) {
if (currentStart < 0) {
currentStart = i;
}
} else if (currentStart >= 0) {
currentLength = i - currentStart;
if (currentLength > shortestLength) {
shortestStart = currentStart;
shortestLength = currentLength;
}
currentStart = -1;
}
}
// If the array ends on a streak of zeros, make sure we account for it
if (currentStart >= 0) {
currentLength = words.length - currentStart;
if (currentLength > shortestLength) {
shortestStart = currentStart;
shortestLength = currentLength;
}
}
// Ignore the longest streak if it is only 1 long
if (shortestLength == 1) {
shortestLength = 0;
shortestStart = -1;
}
// Translate to string taking into account longest consecutive 0s
final int shortestEnd = shortestStart + shortestLength;
final StringBuilder b = new StringBuilder(IPV6_MAX_CHAR_COUNT);
if (shortestEnd < 0) { // Optimization when there is no compressing needed
b.append(Integer.toHexString(words[0]));
for (int i = 1; i < words.length; ++i) {
b.append(':');
b.append(Integer.toHexString(words[i]));
}
} else { // General case that can handle compressing (and not compressing)
// Loop unroll the first index (so we don't constantly check i==0 cases in loop)
final boolean isIpv4Mapped;
if (inRangeEndExclusive(0, shortestStart, shortestEnd)) {
b.append("::");
isIpv4Mapped = ipv4Mapped && (shortestEnd == 5 && words[5] == 0xffff);
} else {
b.append(Integer.toHexString(words[0]));
isIpv4Mapped = false;
}
for (int i = 1; i < words.length; ++i) {
if (!inRangeEndExclusive(i, shortestStart, shortestEnd)) {
if (!inRangeEndExclusive(i - 1, shortestStart, shortestEnd)) {
// If the last index was not part of the shortened sequence
if (!isIpv4Mapped || i == 6) {
b.append(':');
} else {
b.append('.');
}
}
if (isIpv4Mapped && i > 5) {
b.append(words[i] >> 8);
b.append('.');
b.append(words[i] & 0xff);
} else {
b.append(Integer.toHexString(words[i]));
}
} else if (!inRangeEndExclusive(i - 1, shortestStart, shortestEnd)) {
// If we are in the shortened sequence and the last index was not
b.append("::");
}
}
}
return b.toString();
}
/**
* Returns {@link InetSocketAddress#getHostString()} if Java >= 7,
* or {@link InetSocketAddress#getHostName()} otherwise.
* @param addr The address
* @return the host string
*/
public static String getHostname(InetSocketAddress addr) {
return PlatformDependent.javaVersion() >= 7 ? addr.getHostString() : addr.getHostName();
}
/**
* Does a range check on {@code value} if is within {@code start} (inclusive) and {@code end} (exclusive).
* @param value The value to checked if is within {@code start} (inclusive) and {@code end} (exclusive)
* @param start The start of the range (inclusive)
* @param end The end of the range (exclusive)
* @return
*
* - {@code true} if {@code value} if is within {@code start} (inclusive) and {@code end} (exclusive)
* - {@code false} otherwise
*
*/
private static boolean inRangeEndExclusive(int value, int start, int end) {
return value >= start && value < end;
}
/**
* A constructor to stop this class being constructed.
*/
private NetUtil() {
// Unused
}
}