gov.nist.javax.sip.parser.PipelinedMsgParser Maven / Gradle / Ivy
/*
* Conditions Of Use
*
* This software was developed by employees of the National Institute of
* Standards and Technology (NIST), an agency of the Federal Government.
* Pursuant to title 15 Untied States Code Section 105, works of NIST
* employees are not subject to copyright protection in the United States
* and are considered to be in the public domain. As a result, a formal
* license is not needed to use the software.
*
* This software is provided by NIST as a service and is expressly
* provided "AS IS." NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
* AND DATA ACCURACY. NIST does not warrant or make any representations
* regarding the use of the software or the results thereof, including but
* not limited to the correctness, accuracy, reliability or usefulness of
* the software.
*
* Permission to use this software is contingent upon your acceptance
* of the terms of this agreement
*
* .
*
*/
/******************************************************************************
* Product of NIST/ITL Advanced Networking Technologies Division (ANTD) *
******************************************************************************/
package gov.nist.javax.sip.parser;
/*
*
* Lamine Brahimi and Yann Duponchel (IBM Zurich) noticed that the parser was
* blocking so I threw out some cool pipelining which ran fast but only worked
* when the phase of the moon matched its mood. Now things are serialized
* and life goes slower but more reliably.
*
*/
import gov.nist.core.*;
import gov.nist.javax.sip.message.*;
import gov.nist.javax.sip.header.*;
import java.text.ParseException;
import java.io.*;
/**
* This implements a pipelined message parser suitable for use
* with a stream - oriented input such as TCP. The client uses
* this class by instatiating with an input stream from which
* input is read and fed to a message parser.
* It keeps reading from the input stream and process messages in a
* never ending interpreter loop. The message listener interface gets called
* for processing messages or for processing errors. The payload specified
* by the content-length header is read directly from the input stream.
* This can be accessed from the SIPMessage using the getContent and
* getContentBytes methods provided by the SIPMessage class.
*
* @version 1.2 $Revision: 1.19 $ $Date: 2007/01/28 13:06:21 $
*
* @author M. Ranganathan
*
* @see SIPMessageListener
*/
public final class PipelinedMsgParser implements Runnable {
/**
* A filter to read the input
*/
class MyFilterInputStream extends FilterInputStream {
public MyFilterInputStream(InputStream in) {
super(in);
}
}
/**
* The message listener that is registered with this parser.
* (The message listener has methods that can process correct
* and erroneous messages.)
*/
protected SIPMessageListener sipMessageListener;
private Thread mythread; // Preprocessor thread
private byte[] messageBody;
private boolean errorFlag;
private Pipeline rawInputStream;
private int maxMessageSize;
private int sizeCounter;
private int messageSize;
/**
* default constructor.
*/
protected PipelinedMsgParser() {
super();
}
private static int uid = 0;
private static synchronized int getNewUid() {
return uid++;
}
/**
* Constructor when we are given a message listener and an input stream
* (could be a TCP connection or a file)
* @param sipMessageListener Message listener which has
* methods that get called
* back from the parser when a parse is complete
* @param in Input stream from which to read the input.
* @param debug Enable/disable tracing or lexical analyser switch.
*/
public PipelinedMsgParser(
SIPMessageListener sipMessageListener,
Pipeline in,
boolean debug,
int maxMessageSize ) {
this();
this.sipMessageListener = sipMessageListener;
rawInputStream = in;
this.maxMessageSize = maxMessageSize;
mythread = new Thread(this);
mythread.setName("PipelineThread-" + getNewUid());
}
/**
* This is the constructor for the pipelined parser.
* @param mhandler a SIPMessageListener implementation that
* provides the message handlers to
* handle correctly and incorrectly parsed messages.
* @param in An input stream to read messages from.
*/
public PipelinedMsgParser(SIPMessageListener mhandler,
Pipeline in, int maxMsgSize) {
this(mhandler, in, false,maxMsgSize);
}
/**
* This is the constructor for the pipelined parser.
* @param in - An input stream to read messages from.
*/
public PipelinedMsgParser(Pipeline in) {
this(null, in, false,0);
}
/**
* Start reading and processing input.
*/
public void processInput() {
mythread.start();
}
/**
* Create a new pipelined parser from an existing one.
* @return A new pipelined parser that reads from the same input
* stream.
*/
protected Object clone() {
PipelinedMsgParser p = new PipelinedMsgParser();
p.rawInputStream = this.rawInputStream;
p.sipMessageListener = this.sipMessageListener;
Thread mythread = new Thread(p);
mythread.setName("PipelineThread");
return p;
}
/**
* Add a class that implements a SIPMessageListener interface whose
* methods get called * on successful parse and error conditons.
* @param mlistener a SIPMessageListener
* implementation that can react to correct and incorrect
* pars.
*/
public void setMessageListener(SIPMessageListener mlistener) {
sipMessageListener = mlistener;
}
/**
* read a line of input (I cannot use buffered reader because we
* may need to switch encodings mid-stream!
*/
private String readLine(FilterInputStream inputStream) throws IOException {
StringBuffer retval = new StringBuffer("");
while (true) {
try {
char ch;
int i = inputStream.read();
if (i == -1) {
throw new IOException("End of stream");
} else
ch = (char) i;
// reduce the available read size by 1 ("size" of a char).
if ( this.maxMessageSize > 0 ) {
this.sizeCounter --;
if (this.sizeCounter <= 0)
throw new IOException("Max size exceeded!");
}
if (ch != '\r')
retval.append(ch);
if (ch == '\n') {
break;
}
} catch (IOException ex) {
throw ex;
}
}
return retval.toString();
}
/**
* This is input reading thread for the pipelined parser.
* You feed it input through the input stream (see the constructor)
* and it calls back an event listener interface for message
* processing or error.
* It cleans up the input - dealing with things like line continuation
*/
public void run() {
MyFilterInputStream inputStream = null;
inputStream = new MyFilterInputStream(this.rawInputStream);
// I cannot use buffered reader here because we may need to switch
// encodings to read the message body.
try {
while (true) {
this.sizeCounter = this.maxMessageSize;
this.messageSize = 0;
StringBuffer inputBuffer = new StringBuffer();
if (Debug.parserDebug) Debug.println("Starting parse!");
String line1;
String line2 = null;
while (true) {
try {
line1 = readLine(inputStream);
// ignore blank lines.
if (line1.equals("\n")) {
if (Debug.parserDebug)
Debug.println("Discarding " + line1);
continue;
} else
break;
} catch (IOException ex) {
Debug.printStackTrace(ex);
this.rawInputStream.stopTimer();
return;
}
}
inputBuffer.append(line1);
// Guard against bad guys.
this.rawInputStream.startTimer();
while (true) {
try {
line2 = readLine(inputStream);
inputBuffer.append(line2);
if (line2.trim().equals(""))
break;
} catch (IOException ex) {
this.rawInputStream.stopTimer();
Debug.printStackTrace(ex);
return;
}
}
// Stop the timer that will kill the read.
this.rawInputStream.stopTimer();
inputBuffer.append(line2);
StringMsgParser smp = new StringMsgParser(sipMessageListener);
smp.readBody = false;
SIPMessage sipMessage = null;
try {
sipMessage = smp.parseSIPMessage(inputBuffer.toString());
if (sipMessage == null) {
this.rawInputStream.stopTimer();
continue;
}
} catch (ParseException ex) {
// Just ignore the parse exception.
continue;
}
if (Debug.parserDebug) Debug.println("Completed parsing message");
ContentLength cl =
(ContentLength) sipMessage.getContentLength();
int contentLength = 0;
if (cl != null) {
contentLength = cl.getContentLength();
} else {
contentLength = 0;
}
if (Debug.parserDebug) {
Debug.println("contentLength " + contentLength);
Debug.println("sizeCounter " + this.sizeCounter);
Debug.println("maxMessageSize " + this.maxMessageSize);
}
if (contentLength == 0) {
sipMessage.removeContent();
} else if ( maxMessageSize == 0 ||
contentLength < this.sizeCounter ) {
byte[] message_body = new byte[contentLength];
int nread = 0;
while (nread < contentLength ) {
// Start my starvation timer.
//This ensures that the other end
//writes at least some data in
//or we will close the pipe from
//him. This prevents DOS attack
//that takes up all our connections.
this.rawInputStream.startTimer();
try {
int readlength =
inputStream.read(
message_body,
nread,
contentLength - nread);
if (readlength > 0) {
nread += readlength;
} else {
break;
}
} catch (IOException ex) {
ex.printStackTrace();
break;
} finally {
// Stop my starvation timer.
this.rawInputStream.stopTimer();
}
}
sipMessage.setMessageContent(message_body);
}
// Content length too large - process the message and
// return error from there.
if (sipMessageListener != null) {
try {
sipMessageListener.processMessage(sipMessage);
} catch (Exception ex) {
// fatal error in processing - close the
// connection.
break;
}
}
}
} finally {
try {
inputStream.close();
} catch (IOException ioe) {
}
}
}
}
/*
* $Log: PipelinedMsgParser.java,v $
* Revision 1.19 2007/01/28 13:06:21 mranga
* Issue number: 99
* Obtained from:
* Submitted by:
* Reviewed by: mranga
*
* Fixed PRACK handling null pointer exception (for proxy case) and cleanup of unused variables.
*
* CVS: ----------------------------------------------------------------------
* CVS: Issue number:
* CVS: If this change addresses one or more issues,
* CVS: then enter the issue number(s) here.
* CVS: Obtained from:
* CVS: If this change has been taken from another system,
* CVS: then name the system in this line, otherwise delete it.
* CVS: Submitted by:
* CVS: If this code has been contributed to the project by someone else; i.e.,
* CVS: they sent us a patch or a set of diffs, then include their name/email
* CVS: address here. If this is your work then delete this line.
* CVS: Reviewed by:
* CVS: If we are doing pre-commit code reviews and someone else has
* CVS: reviewed your changes, include their name(s) here.
* CVS: If you have not had it reviewed then delete this line.
*
* Revision 1.18 2006/07/13 09:02:10 mranga
* Issue number:
* Obtained from:
* Submitted by: jeroen van bemmel
* Reviewed by: mranga
* Moved some changes from jain-sip-1.2 to java.net
*
* CVS: ----------------------------------------------------------------------
* CVS: Issue number:
* CVS: If this change addresses one or more issues,
* CVS: then enter the issue number(s) here.
* CVS: Obtained from:
* CVS: If this change has been taken from another system,
* CVS: then name the system in this line, otherwise delete it.
* CVS: Submitted by:
* CVS: If this code has been contributed to the project by someone else; i.e.,
* CVS: they sent us a patch or a set of diffs, then include their name/email
* CVS: address here. If this is your work then delete this line.
* CVS: Reviewed by:
* CVS: If we are doing pre-commit code reviews and someone else has
* CVS: reviewed your changes, include their name(s) here.
* CVS: If you have not had it reviewed then delete this line.
*
* Revision 1.4 2006/06/19 06:47:27 mranga
* javadoc fixups
*
* Revision 1.3 2006/06/17 10:18:14 mranga
* Added some synchronization to the sequence number checking.
* Small javadoc fixups
*
* Revision 1.2 2006/06/16 15:26:28 mranga
* Added NIST disclaimer to all public domain files. Clean up some javadoc. Fixed a leak
*
* Revision 1.1.1.1 2005/10/04 17:12:35 mranga
*
* Import
*
*
* Revision 1.16 2004/11/30 23:28:14 mranga
* Issue number: 44
* Submitted by: Rob Daugherty
* Reviewed by: M. Ranganathan
*
* TCP Pipelining truncates content when other end of pipe is closed.
*
* Revision 1.15 2004/05/30 18:55:56 mranga
* Reviewed by: mranga
* Move to timers and eliminate the Transaction scanner Thread
* to improve scalability and reduce cpu usage.
*
* Revision 1.14 2004/05/16 14:13:22 mranga
* Reviewed by: mranga
* Fixed the use-count issue reported by Peter Parnes.
* Added property to prevent against content-length dos attacks.
*
* Revision 1.13 2004/03/19 04:22:22 mranga
* Reviewed by: mranga
* Added IO Pacing for long writes - split write into chunks and flush after each
* chunk to avoid socket back pressure.
*
* Revision 1.12 2004/03/18 22:01:19 mranga
* Reviewed by: mranga
* Get rid of the PipedInputStream from pipelined parser to avoid a copy.
*
* Revision 1.11 2004/03/07 22:25:23 mranga
* Reviewed by: mranga
* Added a new configuration parameter that instructs the stack to
* drop a server connection after server transaction termination
* set gov.nist.javax.sip.CACHE_SERVER_CONNECTIONS=false for this
* Default behavior is true.
*
* Revision 1.10 2004/02/29 15:32:58 mranga
* Reviewed by: mranga
* bug fixes on limiting the max message size.
*
* Revision 1.9 2004/02/29 00:46:34 mranga
* Reviewed by: mranga
* Added new configuration property to limit max message size for TCP transport.
* The property is gov.nist.javax.sip.MAX_MESSAGE_SIZE
*
* Revision 1.8 2004/02/25 21:43:03 mranga
* Reviewed by: mranga
* Added a couple of todo's and removed some debug printlns that could slow
* code down by a bit.
*
* Revision 1.7 2004/02/25 20:52:46 mranga
* Reviewed by: mranga
* Fix TCP transport so messages in excess of 8192 bytes are accepted.
*
* Revision 1.6 2004/01/22 18:39:41 mranga
* Reviewed by: M. Ranganathan
* Moved the ifdef SIMULATION and associated tags to the first column so Prep preprocessor can deal with them.
*
* Revision 1.5 2004/01/22 14:23:45 mranga
* Reviewed by: mranga
* Fixed some minor formatting issues.
*
* Revision 1.4 2004/01/22 13:26:31 sverker
* Issue number:
* Obtained from:
* Submitted by: sverker
* Reviewed by: mranga
*
* Major reformat of code to conform with style guide. Resolved compiler and javadoc warnings. Added CVS tags.
*
* CVS: ----------------------------------------------------------------------
* CVS: Issue number:
* CVS: If this change addresses one or more issues,
* CVS: then enter the issue number(s) here.
* CVS: Obtained from:
* CVS: If this change has been taken from another system,
* CVS: then name the system in this line, otherwise delete it.
* CVS: Submitted by:
* CVS: If this code has been contributed to the project by someone else; i.e.,
* CVS: they sent us a patch or a set of diffs, then include their name/email
* CVS: address here. If this is your work then delete this line.
* CVS: Reviewed by:
* CVS: If we are doing pre-commit code reviews and someone else has
* CVS: reviewed your changes, include their name(s) here.
* CVS: If you have not had it reviewed then delete this line.
*
*/
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