author | rriggs |
Fri, 07 Dec 2018 11:51:17 -0500 | |
changeset 52902 | e3398b2e1ab0 |
parent 48568 | 0255315ac8d4 |
permissions | -rw-r--r-- |
2 | 1 |
/* |
48568 | 2 |
* Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. |
2 | 3 |
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package com.sun.jndi.dns; |
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import javax.naming.CommunicationException; |
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import javax.naming.InvalidNameException; |
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import java.io.IOException; |
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import java.nio.charset.StandardCharsets; |
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/** |
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* The ResourceRecord class represents a DNS resource record. |
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* The string format is based on the master file representation in |
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* RFC 1035. |
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* |
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* @author Scott Seligman |
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*/ |
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public class ResourceRecord { |
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/* |
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48 |
* Resource record type codes |
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*/ |
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50 |
static final int TYPE_A = 1; |
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static final int TYPE_NS = 2; |
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static final int TYPE_CNAME = 5; |
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static final int TYPE_SOA = 6; |
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static final int TYPE_PTR = 12; |
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static final int TYPE_HINFO = 13; |
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static final int TYPE_MX = 15; |
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static final int TYPE_TXT = 16; |
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static final int TYPE_AAAA = 28; |
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static final int TYPE_SRV = 33; |
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static final int TYPE_NAPTR = 35; |
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static final int QTYPE_AXFR = 252; // zone transfer |
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static final int QTYPE_STAR = 255; // query type "*" |
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64 |
/* |
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* Mapping from resource record type codes to type name strings. |
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*/ |
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static final String rrTypeNames[] = { |
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null, "A", "NS", null, null, |
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"CNAME", "SOA", null, null, null, |
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null, null, "PTR", "HINFO", null, |
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"MX", "TXT", null, null, null, |
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null, null, null, null, null, |
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null, null, null, "AAAA", null, |
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null, null, null, "SRV", null, |
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"NAPTR" |
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}; |
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/* |
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* Resource record class codes |
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*/ |
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static final int CLASS_INTERNET = 1; |
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static final int CLASS_HESIOD = 2; |
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static final int QCLASS_STAR = 255; // query class "*" |
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/* |
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* Mapping from resource record type codes to class name strings. |
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*/ |
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static final String rrClassNames[] = { |
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null, "IN", null, null, "HS" |
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}; |
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/* |
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* Maximum number of compression references in labels. |
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* Used to detect compression loops. |
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*/ |
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private static final int MAXIMUM_COMPRESSION_REFERENCES = 16; |
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byte[] msg; // DNS message |
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int msgLen; // msg size (in octets) |
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boolean qSection; // true if this RR is part of question section |
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// and therefore has no ttl or rdata |
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int offset; // offset of RR w/in msg |
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int rrlen; // number of octets in encoded RR |
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DnsName name; // name field of RR, including root label |
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int rrtype; // type field of RR |
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String rrtypeName; // name of rrtype |
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int rrclass; // class field of RR |
108 |
String rrclassName; // name of rrclass |
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int ttl = 0; // ttl field of RR |
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int rdlen = 0; // number of octets of rdata |
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Object rdata = null; // rdata -- most are String, unknown are byte[] |
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/* |
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* Constructs a new ResourceRecord. The encoded data of the DNS |
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* message is contained in msg; data for this RR begins at msg[offset]. |
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* If qSection is true this RR is part of a question section. It's |
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* not a true resource record in that case, but is treated as if it |
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* were a shortened one (with no ttl or rdata). If decodeRdata is |
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* false, the rdata is not decoded (and getRdata() will return null) |
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* unless this is an SOA record. |
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* |
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* @throws CommunicationException if a decoded domain name isn't valid. |
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* @throws ArrayIndexOutOfBoundsException given certain other corrupt data. |
125 |
*/ |
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ResourceRecord(byte[] msg, int msgLen, int offset, |
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boolean qSection, boolean decodeRdata) |
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throws CommunicationException { |
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this.msg = msg; |
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this.msgLen = msgLen; |
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this.offset = offset; |
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this.qSection = qSection; |
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decode(decodeRdata); |
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} |
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public String toString() { |
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String text = name + " " + rrclassName + " " + rrtypeName; |
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if (!qSection) { |
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text += " " + ttl + " " + |
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((rdata != null) ? rdata : "[n/a]"); |
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} |
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return text; |
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} |
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/* |
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* Returns the name field of this RR, including the root label. |
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*/ |
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public DnsName getName() { |
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return name; |
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} |
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153 |
/* |
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* Returns the number of octets in the encoded RR. |
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*/ |
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public int size() { |
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157 |
return rrlen; |
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} |
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160 |
public int getType() { |
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161 |
return rrtype; |
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} |
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164 |
public int getRrclass() { |
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return rrclass; |
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} |
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168 |
public Object getRdata() { |
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return rdata; |
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} |
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public static String getTypeName(int rrtype) { |
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return valueToName(rrtype, rrTypeNames); |
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} |
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177 |
public static int getType(String typeName) { |
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178 |
return nameToValue(typeName, rrTypeNames); |
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} |
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public static String getRrclassName(int rrclass) { |
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return valueToName(rrclass, rrClassNames); |
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} |
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public static int getRrclass(String className) { |
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return nameToValue(className, rrClassNames); |
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} |
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private static String valueToName(int val, String[] names) { |
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String name = null; |
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if ((val > 0) && (val < names.length)) { |
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name = names[val]; |
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} else if (val == QTYPE_STAR) { // QTYPE_STAR == QCLASS_STAR |
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name = "*"; |
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} |
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if (name == null) { |
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name = Integer.toString(val); |
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} |
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return name; |
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} |
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private static int nameToValue(String name, String[] names) { |
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if (name.isEmpty()) { |
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return -1; // invalid name |
205 |
} else if (name.equals("*")) { |
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return QTYPE_STAR; // QTYPE_STAR == QCLASS_STAR |
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} |
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if (Character.isDigit(name.charAt(0))) { |
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try { |
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return Integer.parseInt(name); |
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} catch (NumberFormatException e) { |
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} |
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} |
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for (int i = 1; i < names.length; i++) { |
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if ((names[i] != null) && |
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name.equalsIgnoreCase(names[i])) { |
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return i; |
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} |
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} |
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return -1; // unknown name |
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} |
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/* |
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* Compares two SOA record serial numbers using 32-bit serial number |
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* arithmetic as defined in RFC 1982. Serial numbers are unsigned |
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* 32-bit quantities. Returns a negative, zero, or positive value |
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* as the first serial number is less than, equal to, or greater |
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* than the second. If the serial numbers are not comparable the |
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* result is undefined. Note that the relation is not transitive. |
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*/ |
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public static int compareSerialNumbers(long s1, long s2) { |
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long diff = s2 - s1; |
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if (diff == 0) { |
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return 0; |
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} else if ((diff > 0 && diff <= 0x7FFFFFFF) || |
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(diff < 0 && -diff > 0x7FFFFFFF)) { |
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return -1; |
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} else { |
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return 1; |
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} |
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} |
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/* |
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* Decodes the binary format of the RR. |
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* May throw ArrayIndexOutOfBoundsException given corrupt data. |
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*/ |
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22992 | 248 |
private void decode(boolean decodeRdata) throws CommunicationException { |
2 | 249 |
int pos = offset; // index of next unread octet |
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251 |
name = new DnsName(); // NAME |
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pos = decodeName(pos, name); |
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254 |
rrtype = getUShort(pos); // TYPE |
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rrtypeName = (rrtype < rrTypeNames.length) |
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? rrTypeNames[rrtype] |
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: null; |
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258 |
if (rrtypeName == null) { |
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rrtypeName = Integer.toString(rrtype); |
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} |
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pos += 2; |
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263 |
rrclass = getUShort(pos); // CLASS |
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rrclassName = (rrclass < rrClassNames.length) |
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? rrClassNames[rrclass] |
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: null; |
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267 |
if (rrclassName == null) { |
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rrclassName = Integer.toString(rrclass); |
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} |
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pos += 2; |
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272 |
if (!qSection) { |
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ttl = getInt(pos); // TTL |
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pos += 4; |
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276 |
rdlen = getUShort(pos); // RDLENGTH |
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pos += 2; |
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rdata = (decodeRdata || // RDATA |
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(rrtype == TYPE_SOA)) |
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? decodeRdata(pos) |
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: null; |
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283 |
if (rdata instanceof DnsName) { |
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rdata = rdata.toString(); |
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285 |
} |
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pos += rdlen; |
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287 |
} |
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288 |
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289 |
rrlen = pos - offset; |
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291 |
msg = null; // free up for GC |
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} |
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294 |
/* |
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295 |
* Returns the 1-byte unsigned value at msg[pos]. |
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296 |
*/ |
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297 |
private int getUByte(int pos) { |
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298 |
return (msg[pos] & 0xFF); |
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299 |
} |
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300 |
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301 |
/* |
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302 |
* Returns the 2-byte unsigned value at msg[pos]. The high |
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303 |
* order byte comes first. |
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*/ |
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305 |
private int getUShort(int pos) { |
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306 |
return (((msg[pos] & 0xFF) << 8) | |
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307 |
(msg[pos + 1] & 0xFF)); |
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308 |
} |
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309 |
||
310 |
/* |
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311 |
* Returns the 4-byte signed value at msg[pos]. The high |
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312 |
* order byte comes first. |
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313 |
*/ |
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314 |
private int getInt(int pos) { |
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315 |
return ((getUShort(pos) << 16) | getUShort(pos + 2)); |
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316 |
} |
|
317 |
||
318 |
/* |
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319 |
* Returns the 4-byte unsigned value at msg[pos]. The high |
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320 |
* order byte comes first. |
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321 |
*/ |
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322 |
private long getUInt(int pos) { |
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323 |
return (getInt(pos) & 0xffffffffL); |
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324 |
} |
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325 |
||
326 |
/* |
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327 |
* Returns the name encoded at msg[pos], including the root label. |
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328 |
*/ |
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22992 | 329 |
private DnsName decodeName(int pos) throws CommunicationException { |
2 | 330 |
DnsName n = new DnsName(); |
331 |
decodeName(pos, n); |
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332 |
return n; |
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333 |
} |
|
334 |
||
335 |
/* |
|
336 |
* Prepends to "n" the domain name encoded at msg[pos], including the root |
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337 |
* label. Returns the index into "msg" following the name. |
|
338 |
*/ |
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22992 | 339 |
private int decodeName(int pos, DnsName n) throws CommunicationException { |
340 |
int endPos = -1; |
|
341 |
int level = 0; |
|
342 |
try { |
|
343 |
while (true) { |
|
344 |
if (level > MAXIMUM_COMPRESSION_REFERENCES) |
|
345 |
throw new IOException("Too many compression references"); |
|
346 |
int typeAndLen = msg[pos] & 0xFF; |
|
347 |
if (typeAndLen == 0) { // end of name |
|
348 |
++pos; |
|
349 |
n.add(0, ""); |
|
350 |
break; |
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351 |
} else if (typeAndLen <= 63) { // regular label |
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352 |
++pos; |
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353 |
n.add(0, new String(msg, pos, typeAndLen, |
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354 |
StandardCharsets.ISO_8859_1)); |
|
355 |
pos += typeAndLen; |
|
356 |
} else if ((typeAndLen & 0xC0) == 0xC0) { // name compression |
|
357 |
++level; |
|
48568 | 358 |
// cater for the case where the name pointed to is itself |
359 |
// compressed: we don't want endPos to be reset by the second |
|
360 |
// compression level. |
|
361 |
int ppos = pos; |
|
362 |
if (endPos == -1) endPos = pos + 2; |
|
22992 | 363 |
pos = getUShort(pos) & 0x3FFF; |
48568 | 364 |
if (debug) { |
365 |
dprint("decode: name compression at " + ppos |
|
366 |
+ " -> " + pos + " endPos=" + endPos); |
|
367 |
assert endPos > 0; |
|
368 |
assert pos < ppos; |
|
369 |
assert pos >= Header.HEADER_SIZE; |
|
370 |
} |
|
22992 | 371 |
} else |
372 |
throw new IOException("Invalid label type: " + typeAndLen); |
|
2 | 373 |
} |
22992 | 374 |
} catch (IOException | InvalidNameException e) { |
375 |
CommunicationException ce =new CommunicationException( |
|
376 |
"DNS error: malformed packet"); |
|
377 |
ce.initCause(e); |
|
378 |
throw ce; |
|
2 | 379 |
} |
22992 | 380 |
if (endPos == -1) |
381 |
endPos = pos; |
|
382 |
return endPos; |
|
2 | 383 |
} |
384 |
||
385 |
/* |
|
386 |
* Returns the rdata encoded at msg[pos]. The format is dependent |
|
387 |
* on the rrtype and rrclass values, which have already been set. |
|
388 |
* The length of the encoded data is rdlen, which has already been |
|
389 |
* set. |
|
390 |
* The rdata of records with unknown type/class combinations is |
|
391 |
* returned in a newly-allocated byte array. |
|
392 |
*/ |
|
22992 | 393 |
private Object decodeRdata(int pos) throws CommunicationException { |
2 | 394 |
if (rrclass == CLASS_INTERNET) { |
395 |
switch (rrtype) { |
|
396 |
case TYPE_A: |
|
397 |
return decodeA(pos); |
|
398 |
case TYPE_AAAA: |
|
399 |
return decodeAAAA(pos); |
|
400 |
case TYPE_CNAME: |
|
401 |
case TYPE_NS: |
|
402 |
case TYPE_PTR: |
|
403 |
return decodeName(pos); |
|
404 |
case TYPE_MX: |
|
405 |
return decodeMx(pos); |
|
406 |
case TYPE_SOA: |
|
407 |
return decodeSoa(pos); |
|
408 |
case TYPE_SRV: |
|
409 |
return decodeSrv(pos); |
|
410 |
case TYPE_NAPTR: |
|
411 |
return decodeNaptr(pos); |
|
412 |
case TYPE_TXT: |
|
413 |
return decodeTxt(pos); |
|
414 |
case TYPE_HINFO: |
|
415 |
return decodeHinfo(pos); |
|
416 |
} |
|
417 |
} |
|
418 |
// Unknown RR type/class |
|
48568 | 419 |
if (debug) { |
420 |
dprint("Unknown RR type for RR data: " + rrtype + " rdlen=" + rdlen |
|
421 |
+ ", pos=" + pos +", msglen=" + msg.length + ", remaining=" |
|
422 |
+ (msg.length-pos)); |
|
423 |
} |
|
2 | 424 |
byte[] rd = new byte[rdlen]; |
425 |
System.arraycopy(msg, pos, rd, 0, rdlen); |
|
426 |
return rd; |
|
427 |
} |
|
428 |
||
429 |
/* |
|
430 |
* Returns the rdata of an MX record that is encoded at msg[pos]. |
|
431 |
*/ |
|
22992 | 432 |
private String decodeMx(int pos) throws CommunicationException { |
2 | 433 |
int preference = getUShort(pos); |
434 |
pos += 2; |
|
435 |
DnsName name = decodeName(pos); |
|
436 |
return (preference + " " + name); |
|
437 |
} |
|
438 |
||
439 |
/* |
|
440 |
* Returns the rdata of an SOA record that is encoded at msg[pos]. |
|
441 |
*/ |
|
22992 | 442 |
private String decodeSoa(int pos) throws CommunicationException { |
2 | 443 |
DnsName mname = new DnsName(); |
444 |
pos = decodeName(pos, mname); |
|
445 |
DnsName rname = new DnsName(); |
|
446 |
pos = decodeName(pos, rname); |
|
447 |
||
448 |
long serial = getUInt(pos); |
|
449 |
pos += 4; |
|
450 |
long refresh = getUInt(pos); |
|
451 |
pos += 4; |
|
452 |
long retry = getUInt(pos); |
|
453 |
pos += 4; |
|
454 |
long expire = getUInt(pos); |
|
455 |
pos += 4; |
|
456 |
long minimum = getUInt(pos); // now used as negative TTL |
|
457 |
pos += 4; |
|
458 |
||
459 |
return (mname + " " + rname + " " + serial + " " + |
|
460 |
refresh + " " + retry + " " + expire + " " + minimum); |
|
461 |
} |
|
462 |
||
463 |
/* |
|
464 |
* Returns the rdata of an SRV record that is encoded at msg[pos]. |
|
465 |
* See RFC 2782. |
|
466 |
*/ |
|
22992 | 467 |
private String decodeSrv(int pos) throws CommunicationException { |
2 | 468 |
int priority = getUShort(pos); |
469 |
pos += 2; |
|
470 |
int weight = getUShort(pos); |
|
471 |
pos += 2; |
|
472 |
int port = getUShort(pos); |
|
473 |
pos += 2; |
|
474 |
DnsName target = decodeName(pos); |
|
475 |
return (priority + " " + weight + " " + port + " " + target); |
|
476 |
} |
|
477 |
||
478 |
/* |
|
479 |
* Returns the rdata of an NAPTR record that is encoded at msg[pos]. |
|
480 |
* See RFC 2915. |
|
481 |
*/ |
|
22992 | 482 |
private String decodeNaptr(int pos) throws CommunicationException { |
2 | 483 |
int order = getUShort(pos); |
484 |
pos += 2; |
|
485 |
int preference = getUShort(pos); |
|
486 |
pos += 2; |
|
487 |
StringBuffer flags = new StringBuffer(); |
|
488 |
pos += decodeCharString(pos, flags); |
|
489 |
StringBuffer services = new StringBuffer(); |
|
490 |
pos += decodeCharString(pos, services); |
|
491 |
StringBuffer regexp = new StringBuffer(rdlen); |
|
492 |
pos += decodeCharString(pos, regexp); |
|
493 |
DnsName replacement = decodeName(pos); |
|
494 |
||
495 |
return (order + " " + preference + " " + flags + " " + |
|
496 |
services + " " + regexp + " " + replacement); |
|
497 |
} |
|
498 |
||
499 |
/* |
|
500 |
* Returns the rdata of a TXT record that is encoded at msg[pos]. |
|
501 |
* The rdata consists of one or more <character-string>s. |
|
502 |
*/ |
|
503 |
private String decodeTxt(int pos) { |
|
504 |
StringBuffer buf = new StringBuffer(rdlen); |
|
505 |
int end = pos + rdlen; |
|
506 |
while (pos < end) { |
|
507 |
pos += decodeCharString(pos, buf); |
|
508 |
if (pos < end) { |
|
509 |
buf.append(' '); |
|
510 |
} |
|
511 |
} |
|
512 |
return buf.toString(); |
|
513 |
} |
|
514 |
||
515 |
/* |
|
516 |
* Returns the rdata of an HINFO record that is encoded at msg[pos]. |
|
517 |
* The rdata consists of two <character-string>s. |
|
518 |
*/ |
|
519 |
private String decodeHinfo(int pos) { |
|
520 |
StringBuffer buf = new StringBuffer(rdlen); |
|
521 |
pos += decodeCharString(pos, buf); |
|
522 |
buf.append(' '); |
|
523 |
pos += decodeCharString(pos, buf); |
|
524 |
return buf.toString(); |
|
525 |
} |
|
526 |
||
527 |
/* |
|
528 |
* Decodes the <character-string> at msg[pos] and adds it to buf. |
|
529 |
* If the string contains one of the meta-characters ' ', '\\', or |
|
530 |
* '"', then the result is quoted and any embedded '\\' or '"' |
|
531 |
* chars are escaped with '\\'. Empty strings are also quoted. |
|
532 |
* Returns the size of the encoded string, including the initial |
|
533 |
* length octet. |
|
534 |
*/ |
|
535 |
private int decodeCharString(int pos, StringBuffer buf) { |
|
536 |
int start = buf.length(); // starting index of this string |
|
537 |
int len = getUByte(pos++); // encoded string length |
|
538 |
boolean quoted = (len == 0); // quote string if empty |
|
539 |
for (int i = 0; i < len; i++) { |
|
540 |
int c = getUByte(pos++); |
|
541 |
quoted |= (c == ' '); |
|
542 |
if ((c == '\\') || (c == '"')) { |
|
543 |
quoted = true; |
|
544 |
buf.append('\\'); |
|
545 |
} |
|
546 |
buf.append((char) c); |
|
547 |
} |
|
548 |
if (quoted) { |
|
549 |
buf.insert(start, '"'); |
|
550 |
buf.append('"'); |
|
551 |
} |
|
552 |
return (len + 1); // size includes initial octet |
|
553 |
} |
|
554 |
||
555 |
/* |
|
556 |
* Returns the rdata of an A record, in dotted-decimal format, |
|
557 |
* that is encoded at msg[pos]. |
|
558 |
*/ |
|
559 |
private String decodeA(int pos) { |
|
560 |
return ((msg[pos] & 0xff) + "." + |
|
561 |
(msg[pos + 1] & 0xff) + "." + |
|
562 |
(msg[pos + 2] & 0xff) + "." + |
|
563 |
(msg[pos + 3] & 0xff)); |
|
564 |
} |
|
565 |
||
566 |
/* |
|
567 |
* Returns the rdata of an AAAA record, in colon-separated format, |
|
568 |
* that is encoded at msg[pos]. For example: 4321:0:1:2:3:4:567:89ab. |
|
569 |
* See RFCs 1886 and 2373. |
|
570 |
*/ |
|
571 |
private String decodeAAAA(int pos) { |
|
572 |
int[] addr6 = new int[8]; // the unsigned 16-bit words of the address |
|
573 |
for (int i = 0; i < 8; i++) { |
|
574 |
addr6[i] = getUShort(pos); |
|
575 |
pos += 2; |
|
576 |
} |
|
577 |
||
578 |
// Find longest sequence of two or more zeros, to compress them. |
|
579 |
int curBase = -1; |
|
580 |
int curLen = 0; |
|
581 |
int bestBase = -1; |
|
582 |
int bestLen = 0; |
|
583 |
for (int i = 0; i < 8; i++) { |
|
584 |
if (addr6[i] == 0) { |
|
585 |
if (curBase == -1) { // new sequence |
|
586 |
curBase = i; |
|
587 |
curLen = 1; |
|
588 |
} else { // extend sequence |
|
589 |
++curLen; |
|
590 |
if ((curLen >= 2) && (curLen > bestLen)) { |
|
591 |
bestBase = curBase; |
|
592 |
bestLen = curLen; |
|
593 |
} |
|
594 |
} |
|
595 |
} else { // not in sequence |
|
596 |
curBase = -1; |
|
597 |
} |
|
598 |
} |
|
599 |
||
600 |
// If addr begins with at least 6 zeros and is not :: or ::1, |
|
601 |
// or with 5 zeros followed by 0xffff, use the text format for |
|
602 |
// IPv4-compatible or IPv4-mapped addresses. |
|
603 |
if (bestBase == 0) { |
|
604 |
if ((bestLen == 6) || |
|
605 |
((bestLen == 7) && (addr6[7] > 1))) { |
|
606 |
return ("::" + decodeA(pos - 4)); |
|
607 |
} else if ((bestLen == 5) && (addr6[5] == 0xffff)) { |
|
608 |
return ("::ffff:" + decodeA(pos - 4)); |
|
609 |
} |
|
610 |
} |
|
611 |
||
612 |
// If bestBase != -1, compress zeros in [bestBase, bestBase+bestLen) |
|
613 |
boolean compress = (bestBase != -1); |
|
614 |
||
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
615 |
StringBuilder sb = new StringBuilder(40); |
2 | 616 |
if (bestBase == 0) { |
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
617 |
sb.append(':'); |
2 | 618 |
} |
619 |
for (int i = 0; i < 8; i++) { |
|
620 |
if (!compress || (i < bestBase) || (i >= bestBase + bestLen)) { |
|
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
621 |
sb.append(Integer.toHexString(addr6[i])); |
2 | 622 |
if (i < 7) { |
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
623 |
sb.append(':'); |
2 | 624 |
} |
625 |
} else if (compress && (i == bestBase)) { // first compressed zero |
|
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
626 |
sb.append(':'); |
2 | 627 |
} |
628 |
} |
|
629 |
||
24969
afa6934dd8e8
8041679: Replace uses of StringBuffer with StringBuilder within core library classes
psandoz
parents:
22992
diff
changeset
|
630 |
return sb.toString(); |
2 | 631 |
} |
48568 | 632 |
|
633 |
//------------------------------------------------------------------------- |
|
634 |
||
635 |
private static final boolean debug = false; |
|
636 |
||
637 |
private static void dprint(String mess) { |
|
638 |
if (debug) { |
|
639 |
System.err.println("DNS: " + mess); |
|
640 |
} |
|
641 |
} |
|
642 |
||
2 | 643 |
} |