/*
* JBoss, Home of Professional Open Source.
* Copyright 2014 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* Licensed 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 io.undertow.conduits;
import java.io.
IOException;
import java.nio.
ByteBuffer;
import java.util.zip.
CRC32;
import java.util.zip.
Deflater;
import java.util.zip.
Inflater;
import org.xnio.conduits.
StreamSourceConduit;
import io.undertow.
UndertowMessages;
import io.undertow.server.
ConduitWrapper;
import io.undertow.server.
HttpServerExchange;
import io.undertow.util.
ConduitFactory;
import io.undertow.util.
ObjectPool;
/**
* @author Stuart Douglas
*/
public class
GzipStreamSourceConduit extends
InflatingStreamSourceConduit {
public static final
ConduitWrapper<
StreamSourceConduit>
WRAPPER = new
ConduitWrapper<
StreamSourceConduit>() {
@
Override
public
StreamSourceConduit wrap(
ConduitFactory<
StreamSourceConduit>
factory,
HttpServerExchange exchange) {
return new
GzipStreamSourceConduit(
exchange,
factory.
create());
}
};
private static final int
GZIP_MAGIC = 0x8b1f;
private static final byte[]
HEADER = new byte[]{
(byte)
GZIP_MAGIC, // Magic number (short)
(byte) (
GZIP_MAGIC >> 8), // Magic number (short)
Deflater.
DEFLATED, // Compression method (CM)
0, // Flags (FLG)
0, // Modification time MTIME (int)
0, // Modification time MTIME (int)
0, // Modification time MTIME (int)
0, // Modification time MTIME (int)
0, // Extra flags (XFLG)
0 // Operating system (OS)
};
private final
CRC32 crc = new
CRC32();
public
GzipStreamSourceConduit(
HttpServerExchange exchange,
StreamSourceConduit next) {
super(
exchange,
next);
}
public
GzipStreamSourceConduit(
HttpServerExchange exchange,
StreamSourceConduit next,
ObjectPool<
Inflater>
inflaterPool) {
super(
exchange,
next,
inflaterPool);
}
private int
totalOut;
private int
headerRead = 0;
private int
footerRead = 0;
byte[]
expectedFooter;
protected boolean
readHeader(
ByteBuffer headerData) throws
IOException {
while (
headerRead <
HEADER.length &&
headerData.
hasRemaining()) {
byte
data =
headerData.
get();
if (
headerRead == 0 &&
data !=
HEADER[0]) {
throw
UndertowMessages.
MESSAGES.
invalidGzipHeader();
} else if (
headerRead == 1 &&
data !=
HEADER[1]) {
throw
UndertowMessages.
MESSAGES.
invalidGzipHeader();
}
headerRead++;
}
return
headerRead ==
HEADER.length;
}
protected void
readFooter(
ByteBuffer buf) throws
IOException {
if (
expectedFooter == null) {
byte[]
ret = new byte[8];
int
checksum = (int)
crc.
getValue();
int
total =
totalOut;
ret[0] = (byte) ((
checksum) & 0xFF);
ret[1] = (byte) ((
checksum >> 8) & 0xFF);
ret[2] = (byte) ((
checksum >> 16) & 0xFF);
ret[3] = (byte) ((
checksum >> 24) & 0xFF);
ret[4] = (byte) ((
total) & 0xFF);
ret[5] = (byte) ((
total >> 8) & 0xFF);
ret[6] = (byte) ((
total >> 16) & 0xFF);
ret[7] = (byte) ((
total >> 24) & 0xFF);
expectedFooter =
ret;
}
while (
buf.
hasRemaining() &&
footerRead <
expectedFooter.length) {
byte
data =
buf.
get();
if (
expectedFooter[
footerRead++] !=
data) {
throw
UndertowMessages.
MESSAGES.
invalidGZIPFooter();
}
}
if (
buf.
hasRemaining() &&
footerRead ==
expectedFooter.length) {
throw
UndertowMessages.
MESSAGES.
invalidGZIPFooter();
}
}
protected void
dataDeflated(byte[]
data, int
off, int
len) {
crc.
update(
data,
off,
len);
totalOut +=
len;
}
}