/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* 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.
*/
/**
* @author Alexei Y. Zakharov
*/
package org.apache.harmony.jndi.provider.dns;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.Socket;
import java.net.SocketTimeoutException;
import java.net.UnknownHostException;
import org.apache.harmony.jndi.internal.nls.Messages;
/**
* Contains service methods that are used for transporting DNS messages from DNS
* client to DNS server and vice versa.
*/
public class TransportMgr {
/**
* Sends the packet contained in <code>outBuf</code>, receives the answer
* and stores it in <code>inBuf</code> array.
*
* @param server
* server's IP-address in string form
* @param serverPort
* server port
* @param outBuf
* bytes of the message to send
* @param outBufLen
* length of the <code>outBuf</code>
* @param inBuf
* buffer to store received bytes at
* @param inBufLen
* length of the <code>inBuf</code>
* @param timeout
* time to wait for an answer, in milliseconds; 0 stands for
* infinite timeout
* @return number of received bytes
* @throws SocketTimeoutException
* in case of timeout
* @throws SecurityException
* if security violation error occured; normally this happens if
* the access to the network subsystem has not been granted
* @throws DomainProtocolException
* if some configuration or network problem encountered
*/
public static int sendReceiveUDP(String server, int serverPort,
byte[] outBuf, int outBufLen, byte[] inBuf, int inBufLen,
int timeout) throws DomainProtocolException,
SocketTimeoutException, SecurityException {
byte srvAddrArr[] = null;
InetAddress srvAddr = null;
DatagramSocket dSocket = null;
DatagramPacket inPacket = null;
DatagramPacket outPacket = null;
try {
srvAddrArr = ProviderMgr.parseIpStr(server);
} catch (IllegalArgumentException e) {
// jndi.40=Unable to connect: bad IP address
throw new DomainProtocolException(Messages.getString("jndi.40")); //$NON-NLS-1$
}
try {
dSocket = new DatagramSocket();
srvAddr = InetAddress.getByAddress(srvAddrArr);
dSocket.connect(srvAddr, serverPort);
outPacket = new DatagramPacket(outBuf, outBufLen, srvAddr,
serverPort);
dSocket.setSoTimeout(timeout);
dSocket.send(outPacket);
inPacket = new DatagramPacket(inBuf, inBufLen, srvAddr, serverPort);
dSocket.receive(inPacket);
} catch (IllegalStateException e) {
// jndi.41=Error while querying DNS server
throw new DomainProtocolException(Messages.getString("jndi.41"), e); //$NON-NLS-1$
} catch (SocketTimeoutException e) {
throw (e);
} catch (IOException e) {
// jndi.41=Error while querying DNS server
throw new DomainProtocolException(Messages.getString("jndi.41"), e); //$NON-NLS-1$
} finally {
if (dSocket != null) {
dSocket.close();
}
}
if (inPacket != null) {
return inPacket.getLength();
}
// jndi.42=unknown error
throw new DomainProtocolException(Messages.getString("jndi.42")); //$NON-NLS-1$
}
/**
* Establishes TCP connection, transmit bytes from <code>inBuf</code>,
* stores received answer in <code>outBuf</code>.
*
* @param server
* the server's IP-address in string form
* @param serverPort
* server port
* @param outBuf
* bytes of the message to send
* @param outBufLen
* length of the <code>outBuf</code>
* @param inBuf
* buffer to store received bytes at
* @param inBufLen
* length of the <code>inBuf</code>
* @param timeout
* time to wait for an answer, in milliseconds; 0 stands for
* infinite timeout
* @return number of received bytes
* @throws SocketTimeoutException
* in case of timeout
* @throws SecurityException
* if security violation error occured; normally this happens if
* the access to the network subsystem has not been granted
* @throws DomainProtocolException
* if some configuration or network problem encountered TODO
* pool of connections may speed up things
*/
public static int sendReceiveTCP(String server, int serverPort,
byte[] outBuf, int outBufLen, byte[] inBuf, int inBufLen,
int timeout) throws DomainProtocolException,
SocketTimeoutException, SecurityException {
byte srvAddrArr[] = null;
InetAddress srvAddr = null;
Socket socket = null;
InputStream iStream = null;
BufferedOutputStream oStream = null;
byte tmpArr[] = new byte[2];
int inLen;
int actualLen = -1;
try {
srvAddrArr = ProviderMgr.parseIpStr(server);
} catch (IllegalArgumentException e) {
// jndi.40=Unable to connect: bad IP address
throw new DomainProtocolException(Messages.getString("jndi.40")); //$NON-NLS-1$
}
try {
srvAddr = InetAddress.getByAddress(srvAddrArr);
socket = new Socket(srvAddr, serverPort);
socket.setSoTimeout(timeout);
oStream = new BufferedOutputStream(socket.getOutputStream());
ProviderMgr.write16Int(outBufLen, tmpArr, 0);
oStream.write(tmpArr, 0, 2);
oStream.write(outBuf, 0, outBufLen);
oStream.flush();
iStream = socket.getInputStream();
iStream.read(tmpArr, 0, 2);
inLen = ProviderMgr.parse16Int(tmpArr, 0);
if (inLen > inBufLen) {
// jndi.43=Output buffer is too small
throw new DomainProtocolException(Messages.getString("jndi.43")); //$NON-NLS-1$
}
actualLen = iStream.read(inBuf, 0, inLen);
if (actualLen != inLen) {
// jndi.44=Error while receiving message over TCP
throw new DomainProtocolException(Messages.getString("jndi.44")); //$NON-NLS-1$
}
} catch (IllegalStateException e) {
// jndi.41=Error while querying DNS server
throw new DomainProtocolException(Messages.getString("jndi.41"), e); //$NON-NLS-1$
} catch (SocketTimeoutException e) {
throw (e);
} catch (IOException e) {
// jndi.41=Error while querying DNS server
throw new DomainProtocolException(Messages.getString("jndi.41"), e); //$NON-NLS-1$
} finally {
if (socket != null && !socket.isClosed()) {
try {
socket.close();
} catch (IOException e) {
}
}
}
return actualLen;
}
/**
* Tries to determine IP address by hostname using
* <code>Inet4Address.getByName(String)</code> method.
*
* @return determined address or <code>null</code> if not found
* @see InetAddress#getByName(String)
*/
public static InetAddress getIPByName_OS(String hostname) {
InetAddress addr = null;
try {
addr = InetAddress.getByName(hostname);
} catch (UnknownHostException e) {
// ignore it
}
return addr;
}
}