org.wildfly.openssl.OpenSSLServerHelloExplorer Maven / Gradle / Ivy
/*
* 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.wildfly.openssl;
import java.nio.ByteBuffer;
/**
*/
final class OpenSSLServerHelloExplorer {
// Private constructor prevents construction outside this class.
private OpenSSLServerHelloExplorer() {
}
static int getCipherSuite(ByteBuffer input) {
// What is the handshake type?
byte messageType = input.get();
if (messageType != 22) { // handshake message
return -1;
}
byte helloMajorVersion = input.get();
byte helloMinorVersion = input.get();
int length = getInt16(input);
byte handshakeType = input.get();
if(handshakeType != 2) {
return -1;
}
// What is the handshake body length?
int handshakeLength = getInt24(input);
int result = exploreServerHello(input);
return result;
}
private static int exploreServerHello(ByteBuffer input) {
// server version
byte helloMajorVersion = input.get();
byte helloMinorVersion = input.get();
for (int i = 0; i < 32; ++i) { //the Random is 32 bytes
input.get();
}
// ignore session id
processByteVector8(input);
// get cipher_suite
return getInt16(input);
}
private static int getInt8(ByteBuffer input) {
return input.get();
}
private static int getInt16(ByteBuffer input) {
return (input.get() & 0xFF) << 8 | input.get() & 0xFF;
}
private static int getInt24(ByteBuffer input) {
return (input.get() & 0xFF) << 16 | (input.get() & 0xFF) << 8 |
input.get() & 0xFF;
}
private static void processByteVector8(ByteBuffer input) {
int int8 = getInt8(input);
processByteVector(input, int8);
}
private static void processByteVector(ByteBuffer input, int length) {
for (int i = 0; i < length; ++i) {
input.get();
}
}
}