AbstractSniHandler.java — netty Source File

Source Code

/*
 * Copyright 2017 The Netty Project
 *
 * The Netty Project 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:
 *
 *   https://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.netty.handler.ssl;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.util.CharsetUtil;
import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.ScheduledFuture;

import java.util.Locale;
import java.util.concurrent.TimeUnit;

import static io.netty.util.internal.ObjectUtil.checkPositiveOrZero;

/**
 * <p>Enables <a href="https://tools.ietf.org/html/rfc3546#section-3.1">SNI
 * (Server Name Indication)</a> extension for server side SSL. For clients
 * support SNI, the server could have multiple host name bound on a single IP.
 * The client will send host name in the handshake data so server could decide
 * which certificate to choose for the host name.</p>
 */
public abstract class AbstractSniHandler<T> extends SslClientHelloHandler<T> {

    private static String extractSniHostname(ByteBuf in) {
        // See https://tools.ietf.org/html/rfc5246#section-7.4.1.2
        //
        // Decode the ssl client hello packet.
        //
        // struct {
        //    ProtocolVersion client_version;
        //    Random random;
        //    SessionID session_id;
        //    CipherSuite cipher_suites<2..2^16-2>;
        //    CompressionMethod compression_methods<1..2^8-1>;
        //    select (extensions_present) {
        //        case false:
        //            struct {};
        //        case true:
        //            Extension extensions<0..2^16-1>;
        //    };
        // } ClientHello;
        //

        // We have to skip bytes until SessionID (which sum to 34 bytes in this case).
        int offset = in.readerIndex();
        int endOffset = in.writerIndex();
// ... (162 more lines)