/**
* 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.
*/
package org.apache.hadoop.security;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.security.sasl.Sasl;
import javax.security.sasl.SaslClient;
import javax.security.sasl.SaslException;
import javax.security.sasl.SaslServer;
/**
* A SaslOutputStream is composed of an OutputStream and a SaslServer (or
* SaslClient) so that write() methods first process the data before writing
* them out to the underlying OutputStream. The SaslServer (or SaslClient)
* object must be fully initialized before being used by a SaslOutputStream.
*/
public class SaslOutputStream extends OutputStream {
private final OutputStream outStream;
// processed data ready to be written out
private byte[] saslToken;
private final SaslClient saslClient;
private final SaslServer saslServer;
// buffer holding one byte of incoming data
private final byte[] ibuffer = new byte[1];
private final boolean useWrap;
/**
* Constructs a SASLOutputStream from an OutputStream and a SaslServer <br>
* Note: if the specified OutputStream or SaslServer is null, a
* NullPointerException may be thrown later when they are used.
*
* @param outStream
* the OutputStream to be processed
* @param saslServer
* an initialized SaslServer object
*/
public SaslOutputStream(OutputStream outStream, SaslServer saslServer) {
this.saslServer = saslServer;
this.saslClient = null;
String qop = (String) saslServer.getNegotiatedProperty(Sasl.QOP);
this.useWrap = qop != null && !"auth".equalsIgnoreCase(qop);
if (useWrap) {
this.outStream = new BufferedOutputStream(outStream, 64*1024);
} else {
this.outStream = outStream;
}
}
/**
* Constructs a SASLOutputStream from an OutputStream and a SaslClient <br>
* Note: if the specified OutputStream or SaslClient is null, a
* NullPointerException may be thrown later when they are used.
*
* @param outStream
* the OutputStream to be processed
* @param saslClient
* an initialized SaslClient object
*/
public SaslOutputStream(OutputStream outStream, SaslClient saslClient) {
this.saslServer = null;
this.saslClient = saslClient;
String qop = (String) saslClient.getNegotiatedProperty(Sasl.QOP);
this.useWrap = qop != null && !"auth".equalsIgnoreCase(qop);
if (useWrap) {
this.outStream = new BufferedOutputStream(outStream, 64*1024);
} else {
this.outStream = outStream;
}
}
/**
* Disposes of any system resources or security-sensitive information Sasl
* might be using.
*
* @exception SaslException
* if a SASL error occurs.
*/
private void disposeSasl() throws SaslException {
if (saslClient != null) {
saslClient.dispose();
}
if (saslServer != null) {
saslServer.dispose();
}
}
/**
* Writes the specified byte to this output stream.
*
* @param b
* the <code>byte</code>.
* @exception IOException
* if an I/O error occurs.
*/
public void write(int b) throws IOException {
if (!useWrap) {
outStream.write(b);
return;
}
ibuffer[0] = (byte) b;
write(ibuffer, 0, 1);
}
/**
* Writes <code>b.length</code> bytes from the specified byte array to this
* output stream.
* <p>
* The <code>write</code> method of <code>SASLOutputStream</code> calls the
* <code>write</code> method of three arguments with the three arguments
* <code>b</code>, <code>0</code>, and <code>b.length</code>.
*
* @param b
* the data.
* @exception NullPointerException
* if <code>b</code> is null.
* @exception IOException
* if an I/O error occurs.
*/
public void write(byte[] b) throws IOException {
write(b, 0, b.length);
}
/**
* Writes <code>len</code> bytes from the specified byte array starting at
* offset <code>off</code> to this output stream.
*
* @param inBuf
* the data.
* @param off
* the start offset in the data.
* @param len
* the number of bytes to write.
* @exception IOException
* if an I/O error occurs.
*/
public void write(byte[] inBuf, int off, int len) throws IOException {
if (!useWrap) {
outStream.write(inBuf, off, len);
return;
}
try {
if (saslServer != null) { // using saslServer
saslToken = saslServer.wrap(inBuf, off, len);
} else { // using saslClient
saslToken = saslClient.wrap(inBuf, off, len);
}
} catch (SaslException se) {
try {
disposeSasl();
} catch (SaslException ignored) {
}
throw se;
}
if (saslToken != null) {
ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
DataOutputStream dout = new DataOutputStream(byteOut);
dout.writeInt(saslToken.length);
outStream.write(byteOut.toByteArray());
outStream.write(saslToken, 0, saslToken.length);
saslToken = null;
}
}
/**
* Flushes this output stream
*
* @exception IOException
* if an I/O error occurs.
*/
public void flush() throws IOException {
outStream.flush();
}
/**
* Closes this output stream and releases any system resources associated with
* this stream.
*
* @exception IOException
* if an I/O error occurs.
*/
public void close() throws IOException {
disposeSasl();
outStream.close();
}
}