/*
* 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.coyote.http2;
import java.util.EnumMap;
import java.util.Map;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.res.StringManager;
abstract class ConnectionSettingsBase<T extends Throwable> {
private final Log log = LogFactory.getLog(ConnectionSettingsBase.class);
private final StringManager sm = StringManager.getManager(ConnectionSettingsBase.class);
private final String connectionId;
// Limits
static final int MAX_WINDOW_SIZE = (1 << 31) - 1;
static final int MIN_MAX_FRAME_SIZE = 1 << 14;
static final int MAX_MAX_FRAME_SIZE = (1 << 24) - 1;
static final long UNLIMITED = ((long)1 << 32); // Use the maximum possible
static final int MAX_HEADER_TABLE_SIZE = 1 << 16;
// Defaults
static final int DEFAULT_HEADER_TABLE_SIZE = Hpack.DEFAULT_TABLE_SIZE;
static final boolean DEFAULT_ENABLE_PUSH = true;
static final long DEFAULT_MAX_CONCURRENT_STREAMS = UNLIMITED;
static final int DEFAULT_INITIAL_WINDOW_SIZE = (1 << 16) - 1;
static final int DEFAULT_MAX_FRAME_SIZE = MIN_MAX_FRAME_SIZE;
static final long DEFAULT_MAX_HEADER_LIST_SIZE = UNLIMITED;
Map<Setting, Long> current = new EnumMap<>(Setting.class);
Map<Setting, Long> pending = new EnumMap<>(Setting.class);
ConnectionSettingsBase(String connectionId) {
this.connectionId = connectionId;
// Set up the defaults
current.put(Setting.HEADER_TABLE_SIZE, Long.valueOf(DEFAULT_HEADER_TABLE_SIZE));
current.put(Setting.ENABLE_PUSH, Long.valueOf(DEFAULT_ENABLE_PUSH ? 1 : 0));
current.put(Setting.MAX_CONCURRENT_STREAMS, Long.valueOf(DEFAULT_MAX_CONCURRENT_STREAMS));
current.put(Setting.INITIAL_WINDOW_SIZE, Long.valueOf(DEFAULT_INITIAL_WINDOW_SIZE));
current.put(Setting.MAX_FRAME_SIZE, Long.valueOf(DEFAULT_MAX_FRAME_SIZE));
current.put(Setting.MAX_HEADER_LIST_SIZE, Long.valueOf(DEFAULT_MAX_HEADER_LIST_SIZE));
}
final void set(Setting setting, long value) throws T {
if (log.isDebugEnabled()) {
log.debug(sm.getString("connectionSettings.debug",
connectionId, setting, Long.toString(value)));
}
switch(setting) {
case HEADER_TABLE_SIZE:
validateHeaderTableSize(value);
break;
case ENABLE_PUSH:
validateEnablePush(value);
break;
case MAX_CONCURRENT_STREAMS:
// No further validation required
break;
case INITIAL_WINDOW_SIZE:
validateInitialWindowSize(value);
break;
case MAX_FRAME_SIZE:
validateMaxFrameSize(value);
break;
case MAX_HEADER_LIST_SIZE:
// No further validation required
break;
case UNKNOWN:
// Unrecognised. Ignore it.
log.warn(sm.getString("connectionSettings.unknown",
connectionId, setting, Long.toString(value)));
return;
}
set(setting, Long.valueOf(value));
}
synchronized void set(Setting setting, Long value) {
current.put(setting, value);
}
final int getHeaderTableSize() {
return getMinInt(Setting.HEADER_TABLE_SIZE);
}
final boolean getEnablePush() {
long result = getMin(Setting.ENABLE_PUSH);
return result != 0;
}
final long getMaxConcurrentStreams() {
return getMax(Setting.MAX_CONCURRENT_STREAMS);
}
final int getInitialWindowSize() {
return getMaxInt(Setting.INITIAL_WINDOW_SIZE);
}
final int getMaxFrameSize() {
return getMaxInt(Setting.MAX_FRAME_SIZE);
}
final long getMaxHeaderListSize() {
return getMax(Setting.MAX_HEADER_LIST_SIZE);
}
private synchronized long getMin(Setting setting) {
Long pendingValue = pending.get(setting);
long currentValue = current.get(setting).longValue();
if (pendingValue == null) {
return currentValue;
} else {
return Long.min(pendingValue.longValue(), currentValue);
}
}
private synchronized int getMinInt(Setting setting) {
long result = getMin(setting);
if (result > Integer.MAX_VALUE) {
return Integer.MAX_VALUE;
} else {
return (int) result;
}
}
private synchronized long getMax(Setting setting) {
Long pendingValue = pending.get(setting);
long currentValue = current.get(setting).longValue();
if (pendingValue == null) {
return currentValue;
} else {
return Long.max(pendingValue.longValue(), currentValue);
}
}
private synchronized int getMaxInt(Setting setting) {
long result = getMax(setting);
if (result > Integer.MAX_VALUE) {
return Integer.MAX_VALUE;
} else {
return (int) result;
}
}
private void validateHeaderTableSize(long headerTableSize) throws T {
if (headerTableSize > MAX_HEADER_TABLE_SIZE) {
String msg = sm.getString("connectionSettings.headerTableSizeLimit",
connectionId, Long.toString(headerTableSize));
throwException(msg, Http2Error.PROTOCOL_ERROR);
}
}
private void validateEnablePush(long enablePush) throws T {
// Can't be less than zero since the result of the byte->long conversion
// will never be negative
if (enablePush > 1) {
String msg = sm.getString("connectionSettings.enablePushInvalid",
connectionId, Long.toString(enablePush));
throwException(msg, Http2Error.PROTOCOL_ERROR);
}
}
private void validateInitialWindowSize(long initialWindowSize) throws T {
if (initialWindowSize > MAX_WINDOW_SIZE) {
String msg = sm.getString("connectionSettings.windowSizeTooBig",
connectionId, Long.toString(initialWindowSize), Long.toString(MAX_WINDOW_SIZE));
throwException(msg, Http2Error.FLOW_CONTROL_ERROR);
}
}
private void validateMaxFrameSize(long maxFrameSize) throws T {
if (maxFrameSize < MIN_MAX_FRAME_SIZE || maxFrameSize > MAX_MAX_FRAME_SIZE) {
String msg = sm.getString("connectionSettings.maxFrameSizeInvalid",
connectionId, Long.toString(maxFrameSize), Integer.toString(MIN_MAX_FRAME_SIZE),
Integer.toString(MAX_MAX_FRAME_SIZE));
throwException(msg, Http2Error.PROTOCOL_ERROR);
}
}
abstract void throwException(String msg, Http2Error error) throws T;
}