//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.http2.hpack;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import org.eclipse.jetty.http.HttpField;
import org.eclipse.jetty.http.HttpHeader;
import org.eclipse.jetty.http.HttpMethod;
import org.eclipse.jetty.http.HttpScheme;
import org.eclipse.jetty.util.ArrayQueue;
import org.eclipse.jetty.util.ArrayTernaryTrie;
import org.eclipse.jetty.util.StringUtil;
import org.eclipse.jetty.util.Trie;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
public class HpackContext
{
public static final Logger LOG = Log.getLogger(HpackContext.class);
public static final String[][] STATIC_TABLE =
{
{null,null},
/* 1 */ {":authority",null},
/* 2 */ {":method","GET"},
/* 3 */ {":method","POST"},
/* 4 */ {":path","/"},
/* 5 */ {":path","/index.html"},
/* 6 */ {":scheme","http"},
/* 7 */ {":scheme","https"},
/* 8 */ {":status","200"},
/* 9 */ {":status","204"},
/* 10 */ {":status","206"},
/* 11 */ {":status","304"},
/* 12 */ {":status","400"},
/* 13 */ {":status","404"},
/* 14 */ {":status","500"},
/* 15 */ {"accept-charset",null},
/* 16 */ {"accept-encoding","gzip, deflate"},
/* 17 */ {"accept-language",null},
/* 18 */ {"accept-ranges",null},
/* 19 */ {"accept",null},
/* 20 */ {"access-control-allow-origin",null},
/* 21 */ {"age",null},
/* 22 */ {"allow",null},
/* 23 */ {"authorization",null},
/* 24 */ {"cache-control",null},
/* 25 */ {"content-disposition",null},
/* 26 */ {"content-encoding",null},
/* 27 */ {"content-language",null},
/* 28 */ {"content-length",null},
/* 29 */ {"content-location",null},
/* 30 */ {"content-range",null},
/* 31 */ {"content-type",null},
/* 32 */ {"cookie",null},
/* 33 */ {"date",null},
/* 34 */ {"etag",null},
/* 35 */ {"expect",null},
/* 36 */ {"expires",null},
/* 37 */ {"from",null},
/* 38 */ {"host",null},
/* 39 */ {"if-match",null},
/* 40 */ {"if-modified-since",null},
/* 41 */ {"if-none-match",null},
/* 42 */ {"if-range",null},
/* 43 */ {"if-unmodified-since",null},
/* 44 */ {"last-modified",null},
/* 45 */ {"link",null},
/* 46 */ {"location",null},
/* 47 */ {"max-forwards",null},
/* 48 */ {"proxy-authenticate",null},
/* 49 */ {"proxy-authorization",null},
/* 50 */ {"range",null},
/* 51 */ {"referer",null},
/* 52 */ {"refresh",null},
/* 53 */ {"retry-after",null},
/* 54 */ {"server",null},
/* 55 */ {"set-cookie",null},
/* 56 */ {"strict-transport-security",null},
/* 57 */ {"transfer-encoding",null},
/* 58 */ {"user-agent",null},
/* 59 */ {"vary",null},
/* 60 */ {"via",null},
/* 61 */ {"www-authenticate",null},
};
private static final Map<HttpField,Entry> __staticFieldMap = new HashMap<>();
private static final Trie<Entry> __staticNameMap = new ArrayTernaryTrie<>(true,512);
private static final Entry[] __headerEntryTable = new Entry[HttpHeader.UNKNOWN.ordinal()];
private static final StaticEntry[] __staticTable=new StaticEntry[STATIC_TABLE.length];
static
{
Set<String> added = new HashSet<>();
for (int i=1;i<STATIC_TABLE.length;i++)
{
StaticEntry entry=null;
String name = STATIC_TABLE[i][0];
String value = STATIC_TABLE[i][1];
HttpHeader header = HttpHeader.CACHE.get(name);
if (header!=null && value!=null)
{
switch (header)
{
case C_METHOD:
{
HttpMethod method = HttpMethod.CACHE.get(value);
if (method!=null)
entry=new StaticEntry(i,new StaticTableHttpField(header,name,value,method));
break;
}
case C_SCHEME:
{
HttpScheme scheme = HttpScheme.CACHE.get(value);
if (scheme!=null)
entry=new StaticEntry(i,new StaticTableHttpField(header,name,value,scheme));
break;
}
case C_STATUS:
{
entry=new StaticEntry(i,new StaticTableHttpField(header,name,value,Integer.valueOf(value)));
break;
}
default:
break;
}
}
if (entry==null)
entry=new StaticEntry(i,header==null?new HttpField(STATIC_TABLE[i][0],value):new HttpField(header,name,value));
__staticTable[i]=entry;
if (entry._field.getValue()!=null)
__staticFieldMap.put(entry._field,entry);
if (!added.contains(entry._field.getName()))
{
added.add(entry._field.getName());
__staticNameMap.put(entry._field.getName(),entry);
if (__staticNameMap.get(entry._field.getName())==null)
throw new IllegalStateException("name trie too small");
}
}
for (HttpHeader h : HttpHeader.values())
{
Entry entry = __staticNameMap.get(h.asString());
if (entry!=null)
__headerEntryTable[h.ordinal()]=entry;
}
}
private int _maxHeaderTableSizeInBytes;
private int _headerTableSizeInBytes;
private final HeaderTable _headerTable;
private final Map<HttpField,Entry> _fieldMap = new HashMap<>();
private final Map<String,Entry> _nameMap = new HashMap<>();
HpackContext(int maxHeaderTableSize)
{
_maxHeaderTableSizeInBytes=maxHeaderTableSize;
int guesstimateEntries = 10+maxHeaderTableSize/(32+10+10);
_headerTable=new HeaderTable(guesstimateEntries,guesstimateEntries+10);
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] created max=%d",hashCode(),maxHeaderTableSize));
}
public void resize(int newMaxHeaderTableSize)
{
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] resized max=%d->%d",hashCode(),_maxHeaderTableSizeInBytes,newMaxHeaderTableSize));
_maxHeaderTableSizeInBytes=newMaxHeaderTableSize;
int guesstimateEntries = 10+newMaxHeaderTableSize/(32+10+10);
evict();
_headerTable.resizeUnsafe(guesstimateEntries);
}
public Entry get(HttpField field)
{
Entry entry = _fieldMap.get(field);
if (entry==null)
entry=__staticFieldMap.get(field);
return entry;
}
public Entry get(String name)
{
Entry entry = __staticNameMap.get(name);
if (entry!=null)
return entry;
return _nameMap.get(StringUtil.asciiToLowerCase(name));
}
public Entry get(int index)
{
if (index<__staticTable.length)
return __staticTable[index];
int d=_headerTable.size()-index+__staticTable.length-1;
if (d>=0)
return _headerTable.getUnsafe(d);
return null;
}
public Entry get(HttpHeader header)
{
Entry e = __headerEntryTable[header.ordinal()];
if (e==null)
return get(header.asString());
return e;
}
public static Entry getStatic(HttpHeader header)
{
return __headerEntryTable[header.ordinal()];
}
public Entry add(HttpField field)
{
int slot=_headerTable.getNextSlotUnsafe();
Entry entry=new Entry(slot,field);
int size = entry.getSize();
if (size>_maxHeaderTableSizeInBytes)
{
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] !added size %d>%d",hashCode(),size,_maxHeaderTableSizeInBytes));
return null;
}
_headerTableSizeInBytes+=size;
_headerTable.addUnsafe(entry);
_fieldMap.put(field,entry);
_nameMap.put(StringUtil.asciiToLowerCase(field.getName()),entry);
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] added %s",hashCode(),entry));
evict();
return entry;
}
/**
* @return Current Header table size in entries
*/
public int size()
{
return _headerTable.size();
}
/**
* @return Current Header table size in Octets
*/
public int getHeaderTableSize()
{
return _headerTableSizeInBytes;
}
/**
* @return Max Header table size in Octets
*/
public int getMaxHeaderTableSize()
{
return _maxHeaderTableSizeInBytes;
}
public int index(Entry entry)
{
if (entry._slot<0)
return 0;
if (entry.isStatic())
return entry._slot;
return _headerTable.index(entry)+__staticTable.length-1;
}
public static int staticIndex(HttpHeader header)
{
if (header==null)
return 0;
Entry entry=__staticNameMap.get(header.asString());
if (entry==null)
return 0;
return entry.getSlot();
}
private void evict()
{
while (_headerTableSizeInBytes>_maxHeaderTableSizeInBytes)
{
Entry entry = _headerTable.pollUnsafe();
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] evict %s",hashCode(),entry));
_headerTableSizeInBytes-=entry.getSize();
entry._slot=-1;
_fieldMap.remove(entry.getHttpField());
String lc=StringUtil.asciiToLowerCase(entry.getHttpField().getName());
if (entry==_nameMap.get(lc))
_nameMap.remove(lc);
}
if (LOG.isDebugEnabled())
LOG.debug(String.format("HdrTbl[%x] entries=%d, size=%d, max=%d",hashCode(),_headerTable.size(),_headerTableSizeInBytes,_maxHeaderTableSizeInBytes));
}
@Override
public String toString()
{
return String.format("HpackContext@%x{entries=%d,size=%d,max=%d}",hashCode(),_headerTable.size(),_headerTableSizeInBytes,_maxHeaderTableSizeInBytes);
}
/* ------------------------------------------------------------ */
/**
*/
private class HeaderTable extends ArrayQueue<HpackContext.Entry>
{
/* ------------------------------------------------------------ */
/**
* @param initCapacity
* @param growBy
*/
private HeaderTable(int initCapacity, int growBy)
{
super(initCapacity,growBy);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.util.ArrayQueue#growUnsafe()
*/
@Override
protected void resizeUnsafe(int newCapacity)
{
// Relay on super.growUnsafe to pack all entries 0 to _nextSlot
super.resizeUnsafe(newCapacity);
for (int s=0;s<_nextSlot;s++)
((Entry)_elements[s])._slot=s;
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.util.ArrayQueue#enqueue(java.lang.Object)
*/
@Override
public boolean enqueue(Entry e)
{
return super.enqueue(e);
}
/* ------------------------------------------------------------ */
/**
* @see org.eclipse.jetty.util.ArrayQueue#dequeue()
*/
@Override
public Entry dequeue()
{
return super.dequeue();
}
/* ------------------------------------------------------------ */
/**
* @param entry
* @return
*/
private int index(Entry entry)
{
return entry._slot>=_nextE?_size-entry._slot+_nextE:_nextSlot-entry._slot;
}
}
/* ------------------------------------------------------------ */
/* ------------------------------------------------------------ */
/* ------------------------------------------------------------ */
public static class Entry
{
final HttpField _field;
int _slot;
Entry()
{
_slot=0;
_field=null;
}
Entry(int index,String name, String value)
{
_slot=index;
_field=new HttpField(name,value);
}
Entry(int slot, HttpField field)
{
_slot=slot;
_field=field;
}
public int getSize()
{
return 32+_field.getName().length()+_field.getValue().length();
}
public HttpField getHttpField()
{
return _field;
}
public boolean isStatic()
{
return false;
}
public byte[] getStaticHuffmanValue()
{
return null;
}
public int getSlot()
{
return _slot;
}
public String toString()
{
return String.format("{%s,%d,%s,%x}",isStatic()?"S":"D",_slot,_field,hashCode());
}
}
public static class StaticEntry extends Entry
{
private final byte[] _huffmanValue;
private final byte _encodedField;
StaticEntry(int index,HttpField field)
{
super(index,field);
String value = field.getValue();
if (value!=null && value.length()>0)
{
int huffmanLen = Huffman.octetsNeeded(value);
int lenLen = NBitInteger.octectsNeeded(7,huffmanLen);
_huffmanValue = new byte[1+lenLen+huffmanLen];
ByteBuffer buffer = ByteBuffer.wrap(_huffmanValue);
// Indicate Huffman
buffer.put((byte)0x80);
// Add huffman length
NBitInteger.encode(buffer,7,huffmanLen);
// Encode value
Huffman.encode(buffer,value);
}
else
_huffmanValue=null;
_encodedField=(byte)(0x80|index);
}
@Override
public boolean isStatic()
{
return true;
}
@Override
public byte[] getStaticHuffmanValue()
{
return _huffmanValue;
}
public byte getEncodedField()
{
return _encodedField;
}
}
}