package io.ebeaninternal.server.type;
/*
* Copyright (C) 2008 Google Inc.
*
* Licensed 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.
*/
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Locale;
/**
* Rob Bygrave: This is a copy of the google guava InetAddresses class
* with some features removed.
* <p/>
* <p/>
* Static utility methods pertaining to {@link InetAddress} instances.
* <p/>
* <p><b>Important note:</b> Unlike {@code InetAddress.getByName()}, the
* methods of this class never cause DNS services to be accessed. For
* this reason, you should prefer these methods as much as possible over
* their JDK equivalents whenever you are expecting to handle only
* IP address string literals -- there is no blocking DNS penalty for a
* malformed string.
* <p/>
* <p>This class hooks into the {@code sun.net.util.IPAddressUtil} class
* to make use of the {@code textToNumericFormatV4} and
* {@code textToNumericFormatV6} methods directly as a means to avoid
* accidentally traversing all nameservices (it can be vitally important
* to avoid, say, blocking on DNS at times).
* <p/>
* <p>When dealing with {@link Inet4Address} and {@link Inet6Address}
* objects as byte arrays (vis. {@code InetAddress.getAddress()}) they
* are 4 and 16 bytes in length, respectively, and represent the address
* in network byte order.
* <p/>
* <p>Examples of IP addresses and their byte representations:
* <ul>
* <li>The IPv4 loopback address, {@code "127.0.0.1"}.<br/>
* {@code 7f 00 00 01}
* <p/>
* <li>The IPv6 loopback address, {@code "::1"}.<br/>
* {@code 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01}
* <p/>
* <li>From the IPv6 reserved documentation prefix ({@code 2001:db8::/32}),
* {@code "2001:db8::1"}.<br/>
* {@code 20 01 0d b8 00 00 00 00 00 00 00 00 00 00 00 01}
* <p/>
* <li>An IPv6 "IPv4 compatible" (or "compat") address,
* {@code "::192.168.0.1"}.<br/>
* {@code 00 00 00 00 00 00 00 00 00 00 00 00 c0 a8 00 01}
* <p/>
* <li>An IPv6 "IPv4 mapped" address, {@code "::ffff:192.168.0.1"}.<br/>
* {@code 00 00 00 00 00 00 00 00 00 00 ff ff c0 a8 00 01}
* </ul>
* <p/>
* <p>A few notes about IPv6 "IPv4 mapped" addresses and their observed
* use in Java.
* <br><br>
* "IPv4 mapped" addresses were originally a representation of IPv4
* addresses for use on an IPv6 socket that could receive both IPv4
* and IPv6 connections (by disabling the {@code IPV6_V6ONLY} socket
* option on an IPv6 socket). Yes, it's confusing. Nevertheless,
* these "mapped" addresses were never supposed to be seen on the
* wire. That assumption was dropped, some say mistakenly, in later
* RFCs with the apparent aim of making IPv4-to-IPv6 transition simpler.
* <p/>
* <p>Technically one <i>can</i> create a 128bit IPv6 address with the wire
* format of a "mapped" address, as shown above, and transmit it in an
* IPv6 packet header. However, Java's InetAddress creation methods
* appear to adhere doggedly to the original intent of the "mapped"
* address: all "mapped" addresses return {@link Inet4Address} objects.
* <p/>
* <p>For added safety, it is common for IPv6 network operators to filter
* all packets where either the source or destination address appears to
* be a "compat" or "mapped" address. Filtering suggestions usually
* recommend discarding any packets with source or destination addresses
* in the invalid range {@code ::/3}, which includes both of these bizarre
* address formats. For more information on "bogons", including lists
* of IPv6 bogon space, see:
* <p/>
* <ul>
* <li><a target="_parent"
* href="http://en.wikipedia.org/wiki/Bogon_filtering"
* >http://en.wikipedia.org/wiki/Bogon_filtering</a>
* <li><a target="_parent"
* href="http://www.cymru.com/Bogons/ipv6.txt"
* >http://www.cymru.com/Bogons/ipv6.txt</a>
* <li><a target="_parent"
* href="http://www.cymru.com/Bogons/v6bogon.html"
* >http://www.cymru.com/Bogons/v6bogon.html</a>
* <li><a target="_parent"
* href="http://www.space.net/~gert/RIPE/ipv6-filters.html"
* >http://www.space.net/~gert/RIPE/ipv6-filters.html</a>
* </ul>
*
* @author Erik Kline
* @since 5
*/
public final class ConvertInetAddresses {
private static final int IPV4_PART_COUNT = 4;
private static final int IPV6_PART_COUNT = 8;
private ConvertInetAddresses() {
}
/**
* Returns the {@link InetAddress} having the given string
* representation.
* <p/>
* <p>This deliberately avoids all nameservice lookups (e.g. no DNS).
*
* @param ipString {@code String} containing an IPv4 or IPv6 string literal,
* e.g. {@code "192.168.0.1"} or {@code "2001:db8::1"}
* @return {@link InetAddress} representing the argument
* @throws IllegalArgumentException if the argument is not a valid
* IP string literal
*/
public static InetAddress forString(String ipString) {
byte[] addr = textToNumericFormatV4(ipString);
if (addr == null) {
// Scanning for IPv4 string literal failed; try IPv6.
addr = textToNumericFormatV6(ipString);
}
// The argument was malformed, i.e. not an IP string literal.
if (addr == null) {
throw new IllegalArgumentException(
String.format("'%s' is not an IP string literal.", ipString));
}
try {
return InetAddress.getByAddress(addr);
} catch (UnknownHostException e) {
/*
* This really shouldn't happen in practice since all our byte
* sequences should be valid IP addresses.
*
* However {@link InetAddress#getByAddress} is documented as
* potentially throwing this "if IP address is of illegal length".
*
* This is mapped to IllegalArgumentException since, presumably,
* the argument triggered some processing bug in either
* {@link IPAddressUtil#textToNumericFormatV4} or
* {@link IPAddressUtil#textToNumericFormatV6}.
*/
throw new IllegalArgumentException(String.format("'%s' is extremely broken.", ipString), e);
}
}
/**
* Returns {@code true} if the supplied string is a valid IP string
* literal, {@code false} otherwise.
*
* @param ipString {@code String} to evaluated as an IP string literal
* @return {@code true} if the argument is a valid IP string literal
*/
public static boolean isInetAddress(String ipString) {
try {
forString(ipString);
return true;
} catch (IllegalArgumentException e) {
return false;
}
}
private static byte[] textToNumericFormatV4(String ipString) {
boolean isIpv6 = false;
// handle IPv6 forms of IPv4 addresses
if (ipString.toUpperCase(Locale.US).startsWith("::FFFF:")) {
ipString = ipString.substring(7);
} else if (ipString.startsWith("::")) {
ipString = ipString.substring(2);
isIpv6 = true;
}
String[] address = ipString.split("\\.");
if (address.length != IPV4_PART_COUNT) {
return null;
}
try {
byte[] bytes = new byte[IPV4_PART_COUNT];
for (int i = 0; i < bytes.length; i++) {
int piece = Integer.parseInt(address[i]);
if (piece < 0 || piece > 255) {
return null;
}
// No leading zeroes are allowed. See
// http://tools.ietf.org/html/draft-main-ipaddr-text-rep-00
// section 2.1 for discussion.
if (address[i].startsWith("0") && address[i].length() != 1) {
return null;
}
bytes[i] = (byte) piece;
}
if (isIpv6) { // prepend with zeroes;
byte[] data = new byte[2 * IPV6_PART_COUNT]; // Java initializes arrays to zero
System.arraycopy(bytes, 0, data, 12, IPV4_PART_COUNT);
return data;
} else {
return bytes;
}
} catch (NumberFormatException ex) {
return null;
}
}
private static byte[] textToNumericFormatV6(String ipString) {
if (!ipString.contains(":")) {
return null;
}
if (ipString.contains(":::")) {
return null;
}
if (ipString.contains(".")) {
ipString = convertDottedQuadToHex(ipString);
if (ipString == null) {
return null;
}
}
ipString = padIpString(ipString);
try {
String[] address = ipString.split(":", IPV6_PART_COUNT);
if (address.length != IPV6_PART_COUNT) {
return null;
}
byte[] bytes = new byte[2 * IPV6_PART_COUNT];
for (int i = 0; i < IPV6_PART_COUNT; i++) {
int piece = address[i].isEmpty() ? 0 : Integer.parseInt(address[i], 16);
bytes[2 * i] = (byte) ((piece & 0xFF00) >>> 8);
bytes[2 * i + 1] = (byte) (piece & 0xFF);
}
return bytes;
} catch (NumberFormatException ex) {
return null;
}
}
// Fill in any omitted colons
private static String padIpString(String ipString) {
if (ipString.contains("::")) {
int count = numberOfColons(ipString);
StringBuilder buffer = new StringBuilder("::");
for (int i = 0; i + count < 7; i++) {
buffer.append(":");
}
ipString = ipString.replace("::", buffer);
}
return ipString;
}
private static int numberOfColons(String s) {
int count = 0;
for (int i = 0; i < s.length(); i++) {
if (s.charAt(i) == ':') {
count++;
}
}
return count;
}
private static String convertDottedQuadToHex(String ipString) {
int lastColon = ipString.lastIndexOf(':');
String dottedQuad = ipString.substring(lastColon + 1);
byte[] quad = textToNumericFormatV4(dottedQuad);
if (quad == null) {
return null;
}
String penultimate = Integer.toHexString(((quad[0] & 0xff) << 8) | (quad[1] & 0xff));
String ultimate = Integer.toHexString(((quad[2] & 0xff) << 8) | (quad[3] & 0xff));
String initialPart = ipString.substring(0, lastColon + 1);
return initialPart + penultimate + ":" + ultimate;
}
/**
* Returns the string representation of an {@link InetAddress} suitable
* for inclusion in a URI.
* <p/>
* <p>For IPv4 addresses, this is identical to
* {@link InetAddress#getHostAddress()}, but for IPv6 addresses it
* surrounds this text with square brackets; for example
* {@code "[2001:db8::1]"}.
* <p/>
* <p>Per section 3.2.2 of
* <a target="_parent"
* href="http://tools.ietf.org/html/rfc3986#section-3.2.2"
* >http://tools.ietf.org/html/rfc3986</a>,
* a URI containing an IPv6 string literal is of the form
* {@code "http://[2001:db8::1]:8888/index.html"}.
* <p/>
* <p>Use of either {@link InetAddress#getHostAddress()} or this
* method is recommended over {@link InetAddress#toString()} when an
* IP address string literal is desired. This is because
* {@link InetAddress#toString()} prints the hostname and the IP
* address string joined by a "/".
*
* @param ip {@link InetAddress} to be converted to URI string literal
* @return {@code String} containing URI-safe string literal
*/
public static String toUriString(InetAddress ip) {
if (ip instanceof Inet6Address) {
return "[" + ip.getHostAddress() + "]";
}
return ip.getHostAddress();
}
/**
* Returns an InetAddress representing the literal IPv4 or IPv6 host
* portion of a URL, encoded in the format specified by RFC 3986 section 3.2.2.
* <p/>
* <p>This function is similar to {@link ConvertInetAddresses#forString(String)},
* however, it requires that IPv6 addresses are surrounded by square brackets.
* <p/>
* <p>This function is the inverse of
* {@link ConvertInetAddresses#toUriString(java.net.InetAddress)}.
*
* @param hostAddr A RFC 3986 section 3.2.2 encoded IPv4 or IPv6 address
* @return an InetAddress representing the address in {@code hostAddr}
* @throws IllegalArgumentException if {@code hostAddr} is not a valid
* IPv4 address, or IPv6 address surrounded by square brackets
*/
public static InetAddress forUriString(String hostAddr) {
InetAddress retval;
// IPv4 address?
try {
retval = forString(hostAddr);
if (retval instanceof Inet4Address) {
return retval;
}
} catch (IllegalArgumentException e) {
// Not a valid IP address, fall through.
}
// IPv6 address
if (!(hostAddr.startsWith("[") && hostAddr.endsWith("]"))) {
throw new IllegalArgumentException("Not a valid address: \"" + hostAddr + '"');
}
retval = forString(hostAddr.substring(1, hostAddr.length() - 1));
if (retval instanceof Inet6Address) {
return retval;
}
throw new IllegalArgumentException("Not a valid address: \"" + hostAddr + '"');
}
}