/*
* 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.jk.common;
import java.io.IOException;
import org.apache.jk.core.Msg;
import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.buf.MessageBytes;
/**
* A single packet for communication between the web server and the
* container. Designed to be reused many times with no creation of
* garbage. Understands the format of data types for these packets.
* Can be used (somewhat confusingly) for both incoming and outgoing
* packets.
*
* See Ajp14/Ajp13Packet.java.
*
* @author Henri Gomez [hgomez@apache.org]
* @author Dan Milstein [danmil@shore.net]
* @author Keith Wannamaker [Keith@Wannamaker.org]
* @author Kevin Seguin
* @author Costin Manolache
*/
public class MsgAjp extends Msg {
private static org.apache.juli.logging.Log log=
org.apache.juli.logging.LogFactory.getLog( MsgAjp.class );
// that's the original buffer size in ajp13 - otherwise we'll get interoperability problems.
private byte buf[];
// The current read or write position in the buffer
private int pos;
/**
* This actually means different things depending on whether the
* packet is read or write. For read, it's the length of the
* payload (excluding the header). For write, it's the length of
* the packet as a whole (counting the header). Oh, well.
*/
private int len;
/**
* The maximum packet size
*/
private int bufsize;
/**
* Constructor that takes a buffer size
*/
public MsgAjp(int bsize) {
if(bsize < 8*1024) {
bsize = 8*1024;
}
bufsize = bsize;
buf = new byte[bsize];
}
/**
* No arg constructor.
* @deprecated Use the buffer size constructor.
*/
public MsgAjp() {
this(8*1024);
}
/**
* Prepare this packet for accumulating a message from the container to
* the web server. Set the write position to just after the header
* (but leave the length unwritten, because it is as yet unknown).
*/
public void reset() {
len = 4;
pos = 4;
}
/**
* For a packet to be sent to the web server, finish the process of
* accumulating data and write the length of the data payload into
* the header.
*/
public void end() {
len=pos;
int dLen=len-4;
buf[0] = (byte)0x41;
buf[1] = (byte)0x42;
buf[2]= (byte)((dLen>>>8 ) & 0xFF );
buf[3] = (byte)(dLen & 0xFF);
}
public byte[] getBuffer() {
return buf;
}
public int getLen() {
return len;
}
// ============ Data Writing Methods ===================
/**
* Add an int.
*
* @param val The integer to write.
*/
public void appendInt( int val ) {
buf[pos++] = (byte) ((val >>> 8) & 0xFF);
buf[pos++] = (byte) (val & 0xFF);
}
public void appendByte( int val ) {
buf[pos++] = (byte)val;
}
public void appendLongInt( int val ) {
buf[pos++] = (byte) ((val >>> 24) & 0xFF);
buf[pos++] = (byte) ((val >>> 16) & 0xFF);
buf[pos++] = (byte) ((val >>> 8) & 0xFF);
buf[pos++] = (byte) (val & 0xFF);
}
/**
* Write a String out at the current write position. Strings are
* encoded with the length in two bytes first, then the string, and
* then a terminating \0 (which is <B>not</B> included in the
* encoded length). The terminator is for the convenience of the C
* code, where it saves a round of copying. A null string is
* encoded as a string with length 0.
*/
public void appendBytes(MessageBytes mb) throws IOException {
if(mb==null || mb.isNull() ) {
appendInt( 0);
appendByte(0);
return;
}
// XXX Convert !!
ByteChunk bc= mb.getByteChunk();
appendByteChunk(bc);
}
public void appendByteChunk(ByteChunk bc) throws IOException {
if(bc==null) {
log.error("appendByteChunk() null");
appendInt( 0);
appendByte(0);
return;
}
byte[] bytes = bc.getBytes();
int start=bc.getStart();
int length = bc.getLength();
appendInt( length );
cpBytes(bytes, start, length);
appendByte(0);
}
/**
* Copy a chunk of bytes into the packet, starting at the current
* write position. The chunk of bytes is encoded with the length
* in two bytes first, then the data itself, and finally a
* terminating \0 (which is <B>not</B> included in the encoded
* length).
*
* @param b The array from which to copy bytes.
* @param off The offset into the array at which to start copying
* @param numBytes The number of bytes to copy.
*/
public void appendBytes( byte b[], int off, int numBytes ) {
appendInt( numBytes );
cpBytes( b, off, numBytes );
appendByte(0);
}
private void cpBytes( byte b[], int off, int numBytes ) {
if( pos + numBytes >= buf.length ) {
log.error("Buffer overflow: buffer.len=" + buf.length + " pos=" +
pos + " data=" + numBytes );
dump("Overflow/coBytes");
log.error( "Overflow ", new Throwable());
return;
}
System.arraycopy( b, off, buf, pos, numBytes);
pos += numBytes;
// buf[pos + numBytes] = 0; // Terminating \0
}
// ============ Data Reading Methods ===================
/**
* Read an integer from packet, and advance the read position past
* it. Integers are encoded as two unsigned bytes with the
* high-order byte first, and, as far as I can tell, in
* little-endian order within each byte.
*/
public int getInt() {
int b1 = buf[pos++] & 0xFF; // No swap, Java order
int b2 = buf[pos++] & 0xFF;
return (b1<<8) + b2;
}
public int peekInt() {
int b1 = buf[pos] & 0xFF; // No swap, Java order
int b2 = buf[pos+1] & 0xFF;
return (b1<<8) + b2;
}
public byte getByte() {
byte res = buf[pos++];
return res;
}
public byte peekByte() {
byte res = buf[pos];
return res;
}
public void getBytes(MessageBytes mb) {
int length = getInt();
if( (length == 0xFFFF) || (length == -1) ) {
mb.recycle();
return;
}
mb.setBytes( buf, pos, length );
mb.getCharChunk().recycle();
pos += length;
pos++; // Skip the terminating \0
}
/**
* Copy a chunk of bytes from the packet into an array and advance
* the read position past the chunk. See appendBytes() for details
* on the encoding.
*
* @return The number of bytes copied.
*/
public int getBytes(byte dest[]) {
int length = getInt();
if( length > buf.length ) {
// XXX Should be if(pos + length > buff.legth)?
log.error("getBytes() buffer overflow " + length + " " + buf.length );
}
if( (length == 0xFFFF) || (length == -1) ) {
log.info("Null string " + length);
return 0;
}
System.arraycopy( buf, pos, dest, 0, length );
pos += length;
pos++; // Skip terminating \0 XXX I believe this is wrong but harmless
return length;
}
/**
* Read a 32 bits integer from packet, and advance the read position past
* it. Integers are encoded as four unsigned bytes with the
* high-order byte first, and, as far as I can tell, in
* little-endian order within each byte.
*/
public int getLongInt() {
int b1 = buf[pos++] & 0xFF; // No swap, Java order
b1 <<= 8;
b1 |= (buf[pos++] & 0xFF);
b1 <<= 8;
b1 |= (buf[pos++] & 0xFF);
b1 <<=8;
b1 |= (buf[pos++] & 0xFF);
return b1;
}
public int getHeaderLength() {
return 4;
}
public int processHeader() {
pos = 0;
int mark = getInt();
len = getInt();
if( mark != 0x1234 && mark != 0x4142 ) {
// XXX Logging
log.error("BAD packet signature " + mark);
dump( "In: " );
return -1;
}
if( log.isDebugEnabled() )
log.debug( "Received " + len + " " + buf[0] );
return len;
}
public void dump(String msg) {
if( log.isDebugEnabled() )
log.debug( msg + ": " + buf + " " + pos +"/" + (len + 4));
int max=pos;
if( len + 4 > pos )
max=len+4;
if( max >1000 ) max=1000;
if( log.isDebugEnabled() )
for( int j=0; j < max; j+=16 )
log.debug( hexLine( buf, j, len ));
}
/* -------------------- Utilities -------------------- */
// XXX Move to util package
public static String hexLine( byte buf[], int start, int len ) {
StringBuffer sb=new StringBuffer();
for( int i=start; i< start+16 ; i++ ) {
if( i < len + 4)
sb.append( hex( buf[i] ) + " ");
else
sb.append( " " );
}
sb.append(" | ");
for( int i=start; i < start+16 && i < len + 4; i++ ) {
if( ! Character.isISOControl( (char)buf[i] ))
sb.append( new Character((char)buf[i]) );
else
sb.append( "." );
}
return sb.toString();
}
private static String hex( int x ) {
// if( x < 0) x=256 + x;
String h=Integer.toHexString( x );
if( h.length() == 1 ) h = "0" + h;
return h.substring( h.length() - 2 );
}
}
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