author | jjg |
Wed, 10 Aug 2011 13:44:58 -0700 | |
changeset 10324 | e28265130e4f |
parent 7668 | d4a77089c587 |
child 11913 | be61e1597cc6 |
permissions | -rw-r--r-- |
2 | 1 |
/* |
10324
e28265130e4f
7072353: JNDI libraries do not build with javac -Xlint:all -Werror
jjg
parents:
7668
diff
changeset
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* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved. |
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* 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 java.io.IOException; |
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import java.net.DatagramSocket; |
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import java.net.DatagramPacket; |
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import java.net.InetAddress; |
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import java.net.Socket; |
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import javax.naming.*; |
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import java.util.Collections; |
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import java.util.Map; |
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import java.util.HashMap; |
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import java.util.Set; |
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import java.util.HashSet; |
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// Some of this code began life as part of sun.javaos.net.DnsClient |
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// originally by sritchie@eng 1/96. It was first hacked up for JNDI |
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// use by caveh@eng 6/97. |
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||
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||
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/** |
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* The DnsClient class performs DNS client operations in support of DnsContext. |
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* |
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*/ |
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public class DnsClient { |
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// DNS packet header field offsets |
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private static final int IDENT_OFFSET = 0; |
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private static final int FLAGS_OFFSET = 2; |
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private static final int NUMQ_OFFSET = 4; |
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private static final int NUMANS_OFFSET = 6; |
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private static final int NUMAUTH_OFFSET = 8; |
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private static final int NUMADD_OFFSET = 10; |
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private static final int DNS_HDR_SIZE = 12; |
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// DNS response codes |
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private static final int NO_ERROR = 0; |
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private static final int FORMAT_ERROR = 1; |
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private static final int SERVER_FAILURE = 2; |
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private static final int NAME_ERROR = 3; |
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private static final int NOT_IMPL = 4; |
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private static final int REFUSED = 5; |
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private static final String[] rcodeDescription = { |
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"No error", |
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"DNS format error", |
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"DNS server failure", |
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"DNS name not found", |
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"DNS operation not supported", |
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"DNS service refused" |
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}; |
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private static final int DEFAULT_PORT = 53; |
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private InetAddress[] servers; |
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private int[] serverPorts; |
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private int timeout; // initial timeout on UDP queries in ms |
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private int retries; // number of UDP retries |
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private DatagramSocket udpSocket; |
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// Requests sent |
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private Set<Integer> reqs; |
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// Responses received |
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private Map<Integer, byte[]> resps; |
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//------------------------------------------------------------------------- |
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/* |
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* Each server is of the form "server[:port]". IPv6 literal host names |
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* include delimiting brackets. |
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* "timeout" is the initial timeout interval (in ms) for UDP queries, |
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* and "retries" gives the number of retries per server. |
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*/ |
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public DnsClient(String[] servers, int timeout, int retries) |
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throws NamingException { |
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this.timeout = timeout; |
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this.retries = retries; |
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try { |
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udpSocket = new DatagramSocket(); |
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} catch (java.net.SocketException e) { |
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NamingException ne = new ConfigurationException(); |
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ne.setRootCause(e); |
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throw ne; |
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} |
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this.servers = new InetAddress[servers.length]; |
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serverPorts = new int[servers.length]; |
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for (int i = 0; i < servers.length; i++) { |
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// Is optional port given? |
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int colon = servers[i].indexOf(':', |
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servers[i].indexOf(']') + 1); |
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serverPorts[i] = (colon < 0) |
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? DEFAULT_PORT |
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: Integer.parseInt(servers[i].substring(colon + 1)); |
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String server = (colon < 0) |
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? servers[i] |
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: servers[i].substring(0, colon); |
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try { |
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this.servers[i] = InetAddress.getByName(server); |
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} catch (java.net.UnknownHostException e) { |
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NamingException ne = new ConfigurationException( |
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"Unknown DNS server: " + server); |
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ne.setRootCause(e); |
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throw ne; |
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} |
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} |
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reqs = Collections.synchronizedSet(new HashSet<Integer>()); |
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resps = Collections.synchronizedMap(new HashMap<Integer, byte[]>()); |
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} |
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140 |
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141 |
protected void finalize() { |
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close(); |
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} |
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144 |
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// A lock to access the request and response queues in tandem. |
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private Object queuesLock = new Object(); |
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147 |
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148 |
public void close() { |
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udpSocket.close(); |
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synchronized (queuesLock) { |
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reqs.clear(); |
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resps.clear(); |
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} |
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} |
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private int ident = 0; // used to set the msg ID field |
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private Object identLock = new Object(); |
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159 |
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160 |
/* |
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161 |
* If recursion is true, recursion is requested on the query. |
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* If auth is true, only authoritative responses are accepted; other |
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* responses throw NameNotFoundException. |
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*/ |
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165 |
ResourceRecords query(DnsName fqdn, int qclass, int qtype, |
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boolean recursion, boolean auth) |
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throws NamingException { |
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168 |
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169 |
int xid; |
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synchronized (identLock) { |
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171 |
ident = 0xFFFF & (ident + 1); |
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xid = ident; |
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} |
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174 |
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// enqueue the outstanding request |
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reqs.add(xid); |
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177 |
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Packet pkt = makeQueryPacket(fqdn, xid, qclass, qtype, recursion); |
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Exception caughtException = null; |
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boolean[] doNotRetry = new boolean[servers.length]; |
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182 |
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// |
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// The UDP retry strategy is to try the 1st server, and then |
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// each server in order. If no answer, double the timeout |
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// and try each server again. |
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// |
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188 |
for (int retry = 0; retry < retries; retry++) { |
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// Try each name server. |
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for (int i = 0; i < servers.length; i++) { |
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192 |
if (doNotRetry[i]) { |
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193 |
continue; |
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194 |
} |
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196 |
// send the request packet and wait for a response. |
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197 |
try { |
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198 |
if (debug) { |
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dprint("SEND ID (" + (retry + 1) + "): " + xid); |
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200 |
} |
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byte[] msg = null; |
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msg = doUdpQuery(pkt, servers[i], serverPorts[i], |
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retry, xid); |
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// |
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// If the matching response is not got within the |
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// given timeout, check if the response was enqueued |
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// by some other thread, if not proceed with the next |
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// server or retry. |
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// |
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211 |
if (msg == null) { |
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212 |
if (resps.size() > 0) { |
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msg = lookupResponse(xid); |
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} |
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if (msg == null) { // try next server or retry |
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continue; |
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} |
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} |
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Header hdr = new Header(msg, msg.length); |
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221 |
if (auth && !hdr.authoritative) { |
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caughtException = new NameNotFoundException( |
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"DNS response not authoritative"); |
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doNotRetry[i] = true; |
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continue; |
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} |
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if (hdr.truncated) { // message is truncated -- try TCP |
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// Try each server, starting with the one that just |
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// provided the truncated message. |
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for (int j = 0; j < servers.length; j++) { |
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int ij = (i + j) % servers.length; |
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if (doNotRetry[ij]) { |
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continue; |
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} |
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try { |
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Tcp tcp = |
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new Tcp(servers[ij], serverPorts[ij]); |
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byte[] msg2; |
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try { |
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msg2 = doTcpQuery(tcp, pkt); |
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} finally { |
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tcp.close(); |
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} |
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Header hdr2 = new Header(msg2, msg2.length); |
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if (hdr2.query) { |
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throw new CommunicationException( |
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"DNS error: expecting response"); |
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} |
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checkResponseCode(hdr2); |
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251 |
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252 |
if (!auth || hdr2.authoritative) { |
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// Got a valid response |
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hdr = hdr2; |
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msg = msg2; |
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256 |
break; |
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} else { |
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doNotRetry[ij] = true; |
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} |
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260 |
} catch (Exception e) { |
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// Try next server, or use UDP response |
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262 |
} |
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263 |
} // servers |
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264 |
} |
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return new ResourceRecords(msg, msg.length, hdr, false); |
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266 |
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267 |
} catch (IOException e) { |
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268 |
if (debug) { |
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269 |
dprint("Caught IOException:" + e); |
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270 |
} |
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271 |
if (caughtException == null) { |
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272 |
caughtException = e; |
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273 |
} |
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274 |
// Use reflection to allow pre-1.4 compilation. |
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// This won't be needed much longer. |
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276 |
if (e.getClass().getName().equals( |
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277 |
"java.net.PortUnreachableException")) { |
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278 |
doNotRetry[i] = true; |
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} |
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280 |
} catch (NameNotFoundException e) { |
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throw e; |
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282 |
} catch (CommunicationException e) { |
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283 |
if (caughtException == null) { |
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284 |
caughtException = e; |
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285 |
} |
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286 |
} catch (NamingException e) { |
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287 |
if (caughtException == null) { |
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288 |
caughtException = e; |
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289 |
} |
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290 |
doNotRetry[i] = true; |
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291 |
} |
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292 |
} // servers |
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293 |
} // retries |
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294 |
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295 |
reqs.remove(xid); |
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296 |
if (caughtException instanceof NamingException) { |
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297 |
throw (NamingException) caughtException; |
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298 |
} |
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299 |
// A network timeout or other error occurred. |
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300 |
NamingException ne = new CommunicationException("DNS error"); |
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301 |
ne.setRootCause(caughtException); |
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302 |
throw ne; |
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303 |
} |
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304 |
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305 |
ResourceRecords queryZone(DnsName zone, int qclass, boolean recursion) |
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306 |
throws NamingException { |
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307 |
||
308 |
int xid; |
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309 |
synchronized (identLock) { |
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310 |
ident = 0xFFFF & (ident + 1); |
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311 |
xid = ident; |
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312 |
} |
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313 |
Packet pkt = makeQueryPacket(zone, xid, qclass, |
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314 |
ResourceRecord.QTYPE_AXFR, recursion); |
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315 |
Exception caughtException = null; |
|
316 |
||
317 |
// Try each name server. |
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318 |
for (int i = 0; i < servers.length; i++) { |
|
319 |
try { |
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320 |
Tcp tcp = new Tcp(servers[i], serverPorts[i]); |
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321 |
byte[] msg; |
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322 |
try { |
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323 |
msg = doTcpQuery(tcp, pkt); |
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324 |
Header hdr = new Header(msg, msg.length); |
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325 |
// Check only rcode as per |
|
326 |
// draft-ietf-dnsext-axfr-clarify-04 |
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327 |
checkResponseCode(hdr); |
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328 |
ResourceRecords rrs = |
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329 |
new ResourceRecords(msg, msg.length, hdr, true); |
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330 |
if (rrs.getFirstAnsType() != ResourceRecord.TYPE_SOA) { |
|
331 |
throw new CommunicationException( |
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332 |
"DNS error: zone xfer doesn't begin with SOA"); |
|
333 |
} |
|
334 |
||
335 |
if (rrs.answer.size() == 1 || |
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336 |
rrs.getLastAnsType() != ResourceRecord.TYPE_SOA) { |
|
337 |
// The response is split into multiple DNS messages. |
|
338 |
do { |
|
339 |
msg = continueTcpQuery(tcp); |
|
340 |
if (msg == null) { |
|
341 |
throw new CommunicationException( |
|
342 |
"DNS error: incomplete zone transfer"); |
|
343 |
} |
|
344 |
hdr = new Header(msg, msg.length); |
|
345 |
checkResponseCode(hdr); |
|
346 |
rrs.add(msg, msg.length, hdr); |
|
347 |
} while (rrs.getLastAnsType() != |
|
348 |
ResourceRecord.TYPE_SOA); |
|
349 |
} |
|
350 |
||
351 |
// Delete the duplicate SOA record. |
|
352 |
rrs.answer.removeElementAt(rrs.answer.size() - 1); |
|
353 |
return rrs; |
|
354 |
||
355 |
} finally { |
|
356 |
tcp.close(); |
|
357 |
} |
|
358 |
||
359 |
} catch (IOException e) { |
|
360 |
caughtException = e; |
|
361 |
} catch (NameNotFoundException e) { |
|
362 |
throw e; |
|
363 |
} catch (NamingException e) { |
|
364 |
caughtException = e; |
|
365 |
} |
|
366 |
} |
|
367 |
if (caughtException instanceof NamingException) { |
|
368 |
throw (NamingException) caughtException; |
|
369 |
} |
|
370 |
NamingException ne = new CommunicationException( |
|
371 |
"DNS error during zone transfer"); |
|
372 |
ne.setRootCause(caughtException); |
|
373 |
throw ne; |
|
374 |
} |
|
375 |
||
376 |
||
377 |
/** |
|
378 |
* Tries to retreive an UDP packet matching the given xid |
|
379 |
* received within the timeout. |
|
380 |
* If a packet with different xid is received, the received packet |
|
381 |
* is enqueued with the corresponding xid in 'resps'. |
|
382 |
*/ |
|
383 |
private byte[] doUdpQuery(Packet pkt, InetAddress server, |
|
384 |
int port, int retry, int xid) |
|
385 |
throws IOException, NamingException { |
|
386 |
||
387 |
int minTimeout = 50; // msec after which there are no retries. |
|
388 |
||
389 |
synchronized (udpSocket) { |
|
390 |
DatagramPacket opkt = new DatagramPacket( |
|
391 |
pkt.getData(), pkt.length(), server, port); |
|
392 |
DatagramPacket ipkt = new DatagramPacket(new byte[8000], 8000); |
|
393 |
udpSocket.connect(server, port); |
|
394 |
int pktTimeout = (timeout * (1 << retry)); |
|
395 |
try { |
|
396 |
udpSocket.send(opkt); |
|
397 |
||
398 |
// timeout remaining after successive 'receive()' |
|
399 |
int timeoutLeft = pktTimeout; |
|
400 |
int cnt = 0; |
|
401 |
do { |
|
402 |
if (debug) { |
|
403 |
cnt++; |
|
404 |
dprint("Trying RECEIVE(" + |
|
405 |
cnt + ") retry(" + (retry + 1) + |
|
406 |
") for:" + xid + " sock-timeout:" + |
|
407 |
timeoutLeft + " ms."); |
|
408 |
} |
|
409 |
udpSocket.setSoTimeout(timeoutLeft); |
|
410 |
long start = System.currentTimeMillis(); |
|
411 |
udpSocket.receive(ipkt); |
|
412 |
long end = System.currentTimeMillis(); |
|
413 |
||
414 |
byte[] data = new byte[ipkt.getLength()]; |
|
415 |
data = ipkt.getData(); |
|
416 |
if (isMatchResponse(data, xid)) { |
|
417 |
return data; |
|
418 |
} |
|
419 |
timeoutLeft = pktTimeout - ((int) (end - start)); |
|
420 |
} while (timeoutLeft > minTimeout); |
|
421 |
||
422 |
} finally { |
|
423 |
udpSocket.disconnect(); |
|
424 |
} |
|
425 |
return null; // no matching packet received within the timeout |
|
426 |
} |
|
427 |
} |
|
428 |
||
429 |
/* |
|
430 |
* Sends a TCP query, and returns the first DNS message in the response. |
|
431 |
*/ |
|
432 |
private byte[] doTcpQuery(Tcp tcp, Packet pkt) throws IOException { |
|
433 |
||
434 |
int len = pkt.length(); |
|
435 |
// Send 2-byte message length, then send message. |
|
436 |
tcp.out.write(len >> 8); |
|
437 |
tcp.out.write(len); |
|
438 |
tcp.out.write(pkt.getData(), 0, len); |
|
439 |
tcp.out.flush(); |
|
440 |
||
441 |
byte[] msg = continueTcpQuery(tcp); |
|
442 |
if (msg == null) { |
|
443 |
throw new IOException("DNS error: no response"); |
|
444 |
} |
|
445 |
return msg; |
|
446 |
} |
|
447 |
||
448 |
/* |
|
449 |
* Returns the next DNS message from the TCP socket, or null on EOF. |
|
450 |
*/ |
|
451 |
private byte[] continueTcpQuery(Tcp tcp) throws IOException { |
|
452 |
||
453 |
int lenHi = tcp.in.read(); // high-order byte of response length |
|
454 |
if (lenHi == -1) { |
|
455 |
return null; // EOF |
|
456 |
} |
|
457 |
int lenLo = tcp.in.read(); // low-order byte of response length |
|
458 |
if (lenLo == -1) { |
|
459 |
throw new IOException("Corrupted DNS response: bad length"); |
|
460 |
} |
|
461 |
int len = (lenHi << 8) | lenLo; |
|
462 |
byte[] msg = new byte[len]; |
|
463 |
int pos = 0; // next unfilled position in msg |
|
464 |
while (len > 0) { |
|
465 |
int n = tcp.in.read(msg, pos, len); |
|
466 |
if (n == -1) { |
|
467 |
throw new IOException( |
|
468 |
"Corrupted DNS response: too little data"); |
|
469 |
} |
|
470 |
len -= n; |
|
471 |
pos += n; |
|
472 |
} |
|
473 |
return msg; |
|
474 |
} |
|
475 |
||
476 |
private Packet makeQueryPacket(DnsName fqdn, int xid, |
|
477 |
int qclass, int qtype, boolean recursion) { |
|
478 |
int qnameLen = fqdn.getOctets(); |
|
479 |
int pktLen = DNS_HDR_SIZE + qnameLen + 4; |
|
480 |
Packet pkt = new Packet(pktLen); |
|
481 |
||
482 |
short flags = recursion ? Header.RD_BIT : 0; |
|
483 |
||
484 |
pkt.putShort(xid, IDENT_OFFSET); |
|
485 |
pkt.putShort(flags, FLAGS_OFFSET); |
|
486 |
pkt.putShort(1, NUMQ_OFFSET); |
|
487 |
pkt.putShort(0, NUMANS_OFFSET); |
|
488 |
pkt.putInt(0, NUMAUTH_OFFSET); |
|
489 |
||
490 |
makeQueryName(fqdn, pkt, DNS_HDR_SIZE); |
|
491 |
pkt.putShort(qtype, DNS_HDR_SIZE + qnameLen); |
|
492 |
pkt.putShort(qclass, DNS_HDR_SIZE + qnameLen + 2); |
|
493 |
||
494 |
return pkt; |
|
495 |
} |
|
496 |
||
497 |
// Builds a query name in pkt according to the RFC spec. |
|
498 |
private void makeQueryName(DnsName fqdn, Packet pkt, int off) { |
|
499 |
||
500 |
// Loop through labels, least-significant first. |
|
501 |
for (int i = fqdn.size() - 1; i >= 0; i--) { |
|
502 |
String label = fqdn.get(i); |
|
503 |
int len = label.length(); |
|
504 |
||
505 |
pkt.putByte(len, off++); |
|
506 |
for (int j = 0; j < len; j++) { |
|
507 |
pkt.putByte(label.charAt(j), off++); |
|
508 |
} |
|
509 |
} |
|
510 |
if (!fqdn.hasRootLabel()) { |
|
511 |
pkt.putByte(0, off); |
|
512 |
} |
|
513 |
} |
|
514 |
||
515 |
//------------------------------------------------------------------------- |
|
516 |
||
517 |
private byte[] lookupResponse(Integer xid) throws NamingException { |
|
518 |
// |
|
519 |
// Check the queued responses: some other thread in between |
|
520 |
// received the response for this request. |
|
521 |
// |
|
522 |
if (debug) { |
|
523 |
dprint("LOOKUP for: " + xid + |
|
524 |
"\tResponse Q:" + resps); |
|
525 |
} |
|
526 |
byte[] pkt; |
|
10324
e28265130e4f
7072353: JNDI libraries do not build with javac -Xlint:all -Werror
jjg
parents:
7668
diff
changeset
|
527 |
if ((pkt = resps.get(xid)) != null) { |
5624
302c8bd0d942
6955783: ServiceUnavailableException caught even the secondary DNS is available
weijun
parents:
2
diff
changeset
|
528 |
checkResponseCode(new Header(pkt, pkt.length)); |
2 | 529 |
synchronized (queuesLock) { |
530 |
resps.remove(xid); |
|
531 |
reqs.remove(xid); |
|
532 |
} |
|
533 |
||
534 |
if (debug) { |
|
535 |
dprint("FOUND (" + Thread.currentThread() + |
|
536 |
") for:" + xid); |
|
537 |
} |
|
538 |
} |
|
539 |
return pkt; |
|
540 |
} |
|
541 |
||
542 |
/* |
|
543 |
* Checks the header of an incoming DNS response. |
|
544 |
* Returns true if it matches the given xid and throws a naming |
|
545 |
* exception, if appropriate, based on the response code. |
|
546 |
*/ |
|
547 |
private boolean isMatchResponse(byte[] pkt, int xid) |
|
548 |
throws NamingException { |
|
549 |
||
550 |
Header hdr = new Header(pkt, pkt.length); |
|
551 |
if (hdr.query) { |
|
552 |
throw new CommunicationException("DNS error: expecting response"); |
|
553 |
} |
|
554 |
||
555 |
if (!reqs.contains(xid)) { // already received, ignore the response |
|
556 |
return false; |
|
557 |
} |
|
558 |
||
559 |
// common case- the request sent matches the subsequent response read |
|
560 |
if (hdr.xid == xid) { |
|
561 |
if (debug) { |
|
562 |
dprint("XID MATCH:" + xid); |
|
563 |
} |
|
564 |
||
5624
302c8bd0d942
6955783: ServiceUnavailableException caught even the secondary DNS is available
weijun
parents:
2
diff
changeset
|
565 |
checkResponseCode(hdr); |
2 | 566 |
// remove the response for the xid if received by some other thread. |
567 |
synchronized (queuesLock) { |
|
568 |
resps.remove(xid); |
|
569 |
reqs.remove(xid); |
|
570 |
} |
|
571 |
return true; |
|
572 |
} |
|
573 |
||
574 |
// |
|
575 |
// xid mis-match: enqueue the response, it may belong to some other |
|
576 |
// thread that has not yet had a chance to read its response. |
|
577 |
// enqueue only the first response, responses for retries are ignored. |
|
578 |
// |
|
579 |
synchronized (queuesLock) { |
|
580 |
if (reqs.contains(xid)) { // enqueue only the first response |
|
581 |
resps.put(xid, pkt); |
|
582 |
} |
|
583 |
} |
|
584 |
||
585 |
if (debug) { |
|
586 |
dprint("NO-MATCH SEND ID:" + |
|
587 |
xid + " RECVD ID:" + hdr.xid + |
|
588 |
" Response Q:" + resps + |
|
589 |
" Reqs size:" + reqs.size()); |
|
590 |
} |
|
591 |
return false; |
|
592 |
} |
|
593 |
||
594 |
/* |
|
595 |
* Throws an exception if appropriate for the response code of a |
|
596 |
* given header. |
|
597 |
*/ |
|
598 |
private void checkResponseCode(Header hdr) throws NamingException { |
|
599 |
||
600 |
int rcode = hdr.rcode; |
|
601 |
if (rcode == NO_ERROR) { |
|
602 |
return; |
|
603 |
} |
|
604 |
String msg = (rcode < rcodeDescription.length) |
|
605 |
? rcodeDescription[rcode] |
|
606 |
: "DNS error"; |
|
607 |
msg += " [response code " + rcode + "]"; |
|
608 |
||
609 |
switch (rcode) { |
|
610 |
case SERVER_FAILURE: |
|
611 |
throw new ServiceUnavailableException(msg); |
|
612 |
case NAME_ERROR: |
|
613 |
throw new NameNotFoundException(msg); |
|
614 |
case NOT_IMPL: |
|
615 |
case REFUSED: |
|
616 |
throw new OperationNotSupportedException(msg); |
|
617 |
case FORMAT_ERROR: |
|
618 |
default: |
|
619 |
throw new NamingException(msg); |
|
620 |
} |
|
621 |
} |
|
622 |
||
623 |
//------------------------------------------------------------------------- |
|
624 |
||
625 |
private static boolean debug = false; |
|
626 |
||
627 |
public static void setDebug(boolean flag) { |
|
628 |
debug = flag; |
|
629 |
} |
|
630 |
||
631 |
private static void dprint(String mess) { |
|
632 |
if (debug) { |
|
633 |
System.err.println("DNS: " + mess); |
|
634 |
} |
|
635 |
} |
|
636 |
||
637 |
} |
|
638 |
||
639 |
class Tcp { |
|
640 |
||
641 |
private Socket sock; |
|
642 |
java.io.InputStream in; |
|
643 |
java.io.OutputStream out; |
|
644 |
||
645 |
Tcp(InetAddress server, int port) throws IOException { |
|
646 |
sock = new Socket(server, port); |
|
647 |
sock.setTcpNoDelay(true); |
|
648 |
out = new java.io.BufferedOutputStream(sock.getOutputStream()); |
|
649 |
in = new java.io.BufferedInputStream(sock.getInputStream()); |
|
650 |
} |
|
651 |
||
652 |
void close() throws IOException { |
|
653 |
sock.close(); |
|
654 |
} |
|
655 |
} |
|
656 |
||
657 |
/* |
|
658 |
* javaos emulation -cj |
|
659 |
*/ |
|
660 |
class Packet { |
|
661 |
byte buf[]; |
|
662 |
||
663 |
Packet(int len) { |
|
664 |
buf = new byte[len]; |
|
665 |
} |
|
666 |
||
667 |
Packet(byte data[], int len) { |
|
668 |
buf = new byte[len]; |
|
669 |
System.arraycopy(data, 0, buf, 0, len); |
|
670 |
} |
|
671 |
||
672 |
void putInt(int x, int off) { |
|
673 |
buf[off + 0] = (byte)(x >> 24); |
|
674 |
buf[off + 1] = (byte)(x >> 16); |
|
675 |
buf[off + 2] = (byte)(x >> 8); |
|
676 |
buf[off + 3] = (byte)x; |
|
677 |
} |
|
678 |
||
679 |
void putShort(int x, int off) { |
|
680 |
buf[off + 0] = (byte)(x >> 8); |
|
681 |
buf[off + 1] = (byte)x; |
|
682 |
} |
|
683 |
||
684 |
void putByte(int x, int off) { |
|
685 |
buf[off] = (byte)x; |
|
686 |
} |
|
687 |
||
688 |
void putBytes(byte src[], int src_offset, int dst_offset, int len) { |
|
689 |
System.arraycopy(src, src_offset, buf, dst_offset, len); |
|
690 |
} |
|
691 |
||
692 |
int length() { |
|
693 |
return buf.length; |
|
694 |
} |
|
695 |
||
696 |
byte[] getData() { |
|
697 |
return buf; |
|
698 |
} |
|
699 |
} |