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* 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.
*
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package com.sun.jndi.ldap.sasl;
import javax.security.sasl.Sasl;
import javax.security.sasl.SaslClient;
import javax.security.sasl.SaslException;
import java.io.IOException;
import java.io.EOFException;
import java.io.InputStream;
/**
* This class is used by clients of Java SASL that need to create an input stream
* that uses SaslClient's unwrap() method to decode the SASL buffers
* sent by the SASL server.
*
* Extend from InputStream instead of FilterInputStream because
* we need to override less methods in InputStream. That is, the
* behavior of the default implementations in InputStream matches
* more closely with the behavior we want in SaslInputStream.
*
* @author Rosanna Lee
*/
public class SaslInputStream extends InputStream {
private static final boolean debug = false;
private byte[] saslBuffer; // buffer for storing raw bytes
private byte[] lenBuf = new byte[4]; // buffer for storing length
private byte[] buf = new byte[0]; // buffer for storing processed bytes
// Initialized to empty buffer
private int bufPos = 0; // read position in buf
private InputStream in; // underlying input stream
private SaslClient sc;
private int recvMaxBufSize = 65536;
SaslInputStream(SaslClient sc, InputStream in) throws SaslException {
super();
this.in = in;
this.sc = sc;
String str = (String) sc.getNegotiatedProperty(Sasl.MAX_BUFFER);
if (str != null) {
try {
recvMaxBufSize = Integer.parseInt(str);
} catch (NumberFormatException e) {
throw new SaslException(Sasl.MAX_BUFFER +
" property must be numeric string: " + str);
}
}
saslBuffer = new byte[recvMaxBufSize];
}
public int read() throws IOException {
byte[] inBuf = new byte[1];
int count = read(inBuf, 0, 1);
if (count > 0) {
return inBuf[0];
} else {
return -1;
}
}
public int read(byte[] inBuf, int start, int count) throws IOException {
if (bufPos >= buf.length) {
int actual = fill(); // read and unwrap next SASL buffer
while (actual == 0) { // ignore zero length content
actual = fill();
}
if (actual == -1) {
return -1; // EOF
}
}
int avail = buf.length - bufPos;
if (count > avail) {
// Requesting more that we have stored
// Return all that we have; next invocation of read() will
// trigger fill()
System.arraycopy(buf, bufPos, inBuf, start, avail);
bufPos = buf.length;
return avail;
} else {
// Requesting less than we have stored
// Return all that was requested
System.arraycopy(buf, bufPos, inBuf, start, count);
bufPos += count;
return count;
}
}
/**
* Fills the buf with more data by reading a SASL buffer, unwrapping it,
* and leaving the bytes in buf for read() to return.
* @return The number of unwrapped bytes available
*/
private int fill() throws IOException {
// Read in length of buffer
int actual = readFully(lenBuf, 4);
if (actual != 4) {
return -1;
}
int len = networkByteOrderToInt(lenBuf, 0, 4);
if (len > recvMaxBufSize) {
throw new IOException(
len + "exceeds the negotiated receive buffer size limit:" +
recvMaxBufSize);
}
if (debug) {
System.err.println("reading " + len + " bytes from network");
}
// Read SASL buffer
actual = readFully(saslBuffer, len);
if (actual != len) {
throw new EOFException("Expecting to read " + len +
" bytes but got " + actual + " bytes before EOF");
}
// Unwrap
buf = sc.unwrap(saslBuffer, 0, len);
bufPos = 0;
return buf.length;
}
/**
* Read requested number of bytes before returning.
* @return The number of bytes actually read; -1 if none read
*/
private int readFully(byte[] inBuf, int total) throws IOException {
int count, pos = 0;
if (debug) {
System.err.println("readFully " + total + " from " + in);
}
while (total > 0) {
count = in.read(inBuf, pos, total);
if (debug) {
System.err.println("readFully read " + count);
}
if (count == -1 ) {
return (pos == 0? -1 : pos);
}
pos += count;
total -= count;
}
return pos;
}
public int available() throws IOException {
return buf.length - bufPos;
}
public void close() throws IOException {
SaslException save = null;
try {
sc.dispose(); // Dispose of SaslClient's state
} catch (SaslException e) {
// Save exception for throwing after closing 'in'
save = e;
}
in.close(); // Close underlying input stream
if (save != null) {
throw save;
}
}
/**
* Returns the integer represented by 4 bytes in network byte order.
*/
// Copied from com.sun.security.sasl.util.SaslImpl.
private static int networkByteOrderToInt(byte[] buf, int start, int count) {
if (count > 4) {
throw new IllegalArgumentException("Cannot handle more than 4 bytes");
}
int answer = 0;
for (int i = 0; i < count; i++) {
answer <<= 8;
answer |= ((int)buf[start+i] & 0xff);
}
return answer;
}
}