io.grpc.netty.JettyTlsUtil Maven / Gradle / Ivy
/*
* Copyright 2015 The gRPC Authors
*
* 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.grpc.netty;
import java.lang.reflect.Method;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;
/**
* Utility class for determining support for Jetty TLS ALPN/NPN.
*/
final class JettyTlsUtil {
private JettyTlsUtil() {
}
private static Throwable jettyAlpnUnavailabilityCause;
private static Throwable jettyNpnUnavailabilityCause;
private static class Java9AlpnUnavailabilityCauseHolder {
@SuppressWarnings("StaticAssignmentOfThrowable")
static final Throwable cause = checkAlpnAvailability();
static Throwable checkAlpnAvailability() {
try {
SSLContext context = SSLContext.getInstance("TLS");
context.init(null, null, null);
SSLEngine engine = context.createSSLEngine();
Method getApplicationProtocol = SSLEngine.class.getMethod("getApplicationProtocol");
getApplicationProtocol.invoke(engine);
return null;
} catch (Throwable t) {
return t;
}
}
}
/** Indicates whether or not the Jetty ALPN jar is installed in the boot classloader. */
@SuppressWarnings("StaticAssignmentOfThrowable")
static synchronized boolean isJettyAlpnConfigured() {
try {
Class.forName("org.eclipse.jetty.alpn.ALPN", true, null);
return true;
} catch (ClassNotFoundException e) {
jettyAlpnUnavailabilityCause = e;
return false;
}
}
static synchronized Throwable getJettyAlpnUnavailabilityCause() {
// This case should be unlikely
if (jettyAlpnUnavailabilityCause == null) {
@SuppressWarnings("UnusedVariable")
boolean discard = isJettyAlpnConfigured();
}
return jettyAlpnUnavailabilityCause;
}
/** Indicates whether or not the Jetty NPN jar is installed in the boot classloader. */
@SuppressWarnings("StaticAssignmentOfThrowable")
static synchronized boolean isJettyNpnConfigured() {
try {
Class.forName("org.eclipse.jetty.npn.NextProtoNego", true, null);
return true;
} catch (ClassNotFoundException e) {
jettyNpnUnavailabilityCause = e;
return false;
}
}
static synchronized Throwable getJettyNpnUnavailabilityCause() {
// This case should be unlikely
if (jettyNpnUnavailabilityCause == null) {
@SuppressWarnings("UnusedVariable")
boolean discard = isJettyNpnConfigured();
}
return jettyNpnUnavailabilityCause;
}
/**
* Indicates whether Java 9 ALPN is available.
*/
static boolean isJava9AlpnAvailable() {
return getJava9AlpnUnavailabilityCause() == null;
}
static Throwable getJava9AlpnUnavailabilityCause() {
return Java9AlpnUnavailabilityCauseHolder.cause;
}
}