Java examples for Network:IP Address
is IPv6 Literal Address
/*// w ww . j a v a2 s . com * Copyright (c) 2004, 2015, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ //package com.java2s; public class Main { public static void main(String[] argv) throws Exception { String src = "java2s.com"; System.out.println(isIPv6LiteralAddress(src)); } private static final int INADDR4SZ = 4; private static final int INADDR16SZ = 16; private static final int INT16SZ = 2; /** * @param src a String representing an IPv6 address in textual format * @return a boolean indicating whether src is an IPv6 literal address */ public static boolean isIPv6LiteralAddress(String src) { return textToNumericFormatV6(src) != null; } public static byte[] textToNumericFormatV6(String src) { // Shortest valid string is "::", hence at least 2 chars if (src.length() < 2) { return null; } int colonp; char ch; boolean saw_xdigit; int val; char[] srcb = src.toCharArray(); byte[] dst = new byte[INADDR16SZ]; int srcb_length = srcb.length; int pc = src.indexOf('%'); if (pc == srcb_length - 1) { return null; } if (pc != -1) { srcb_length = pc; } colonp = -1; int i = 0, j = 0; /* Leading :: requires some special handling. */ if (srcb[i] == ':') if (srcb[++i] != ':') return null; int curtok = i; saw_xdigit = false; val = 0; while (i < srcb_length) { ch = srcb[i++]; int chval = Character.digit(ch, 16); if (chval != -1) { val <<= 4; val |= chval; if (val > 0xffff) return null; saw_xdigit = true; continue; } if (ch == ':') { curtok = i; if (!saw_xdigit) { if (colonp != -1) return null; colonp = j; continue; } else if (i == srcb_length) { return null; } if (j + INT16SZ > INADDR16SZ) return null; dst[j++] = (byte) ((val >> 8) & 0xff); dst[j++] = (byte) (val & 0xff); saw_xdigit = false; val = 0; continue; } if (ch == '.' && ((j + INADDR4SZ) <= INADDR16SZ)) { String ia4 = src.substring(curtok, srcb_length); /* check this IPv4 address has 3 dots, ie. A.B.C.D */ int dot_count = 0, index = 0; while ((index = ia4.indexOf('.', index)) != -1) { dot_count++; index++; } if (dot_count != 3) { return null; } byte[] v4addr = textToNumericFormatV4(ia4); if (v4addr == null) { return null; } for (int k = 0; k < INADDR4SZ; k++) { dst[j++] = v4addr[k]; } saw_xdigit = false; break; /* '\0' was seen by inet_pton4(). */ } return null; } if (saw_xdigit) { if (j + INT16SZ > INADDR16SZ) return null; dst[j++] = (byte) ((val >> 8) & 0xff); dst[j++] = (byte) (val & 0xff); } if (colonp != -1) { int n = j - colonp; if (j == INADDR16SZ) return null; for (i = 1; i <= n; i++) { dst[INADDR16SZ - i] = dst[colonp + n - i]; dst[colonp + n - i] = 0; } j = INADDR16SZ; } if (j != INADDR16SZ) return null; byte[] newdst = convertFromIPv4MappedAddress(dst); if (newdst != null) { return newdst; } else { return dst; } } @SuppressWarnings("fallthrough") public static byte[] textToNumericFormatV4(String src) { byte[] res = new byte[INADDR4SZ]; long tmpValue = 0; int currByte = 0; boolean newOctet = true; int len = src.length(); if (len == 0 || len > 15) { return null; } /* * When only one part is given, the value is stored directly in * the network address without any byte rearrangement. * * When a two part address is supplied, the last part is * interpreted as a 24-bit quantity and placed in the right * most three bytes of the network address. This makes the * two part address format convenient for specifying Class A * network addresses as net.host. * * When a three part address is specified, the last part is * interpreted as a 16-bit quantity and placed in the right * most two bytes of the network address. This makes the * three part address format convenient for specifying * Class B net- work addresses as 128.net.host. * * When four parts are specified, each is interpreted as a * byte of data and assigned, from left to right, to the * four bytes of an IPv4 address. * * We determine and parse the leading parts, if any, as single * byte values in one pass directly into the resulting byte[], * then the remainder is treated as a 8-to-32-bit entity and * translated into the remaining bytes in the array. */ for (int i = 0; i < len; i++) { char c = src.charAt(i); if (c == '.') { if (newOctet || tmpValue < 0 || tmpValue > 0xff || currByte == 3) { return null; } res[currByte++] = (byte) (tmpValue & 0xff); tmpValue = 0; newOctet = true; } else { int digit = Character.digit(c, 10); if (digit < 0) { return null; } tmpValue *= 10; tmpValue += digit; newOctet = false; } } if (newOctet || tmpValue < 0 || tmpValue >= (1L << ((4 - currByte) * 8))) { return null; } switch (currByte) { case 0: res[0] = (byte) ((tmpValue >> 24) & 0xff); case 1: res[1] = (byte) ((tmpValue >> 16) & 0xff); case 2: res[2] = (byte) ((tmpValue >> 8) & 0xff); case 3: res[3] = (byte) ((tmpValue >> 0) & 0xff); } return res; } public static byte[] convertFromIPv4MappedAddress(byte[] addr) { if (isIPv4MappedAddress(addr)) { byte[] newAddr = new byte[INADDR4SZ]; System.arraycopy(addr, 12, newAddr, 0, INADDR4SZ); return newAddr; } return null; } /** * Utility routine to check if the InetAddress is an * IPv4 mapped IPv6 address. * * @return a <code>boolean</code> indicating if the InetAddress is * an IPv4 mapped IPv6 address; or false if address is IPv4 address. */ private static boolean isIPv4MappedAddress(byte[] addr) { if (addr.length < INADDR16SZ) { return false; } if ((addr[0] == 0x00) && (addr[1] == 0x00) && (addr[2] == 0x00) && (addr[3] == 0x00) && (addr[4] == 0x00) && (addr[5] == 0x00) && (addr[6] == 0x00) && (addr[7] == 0x00) && (addr[8] == 0x00) && (addr[9] == 0x00) && (addr[10] == (byte) 0xff) && (addr[11] == (byte) 0xff)) { return true; } return false; } }