Fix SSL configuration with Reactor Netty

Prior to this commit, the SslServerCustomizer would use a Reactor Netty
API that lets users customize the SSL configuration, but later override
some of the choices with defaults.

This commits moves from the new deprecated Reactor Netty API and instead
uses a new variant that builds the defaults and lets developers override
them if they want to.

Fixes gh-25913

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/cloudfoundry/reactive/ReactiveCloudFoundrySecurityService.java

@@ -20,10 +20,10 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-import io.netty.handler.ssl.SslContextBuilder;
 import io.netty.handler.ssl.SslProvider;
 import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
 import reactor.core.publisher.Mono;
+import reactor.netty.http.Http11SslContextSpec;
 import reactor.netty.http.client.HttpClient;
 
 import org.springframework.boot.actuate.autoconfigure.cloudfoundry.AccessLevel;
@@ -66,14 +66,13 @@ class ReactiveCloudFoundrySecurityService {
 	}
 
 	protected ReactorClientHttpConnector buildTrustAllSslConnector() {
-		HttpClient client = HttpClient.create()
-				.secure((sslContextSpec) -> sslContextSpec.sslContext(createSslContext()));
+		HttpClient client = HttpClient.create().secure((spec) -> spec.sslContext(createSslContextSpec()));
 		return new ReactorClientHttpConnector(client);
 	}
 
-	private SslContextBuilder createSslContext() {
-		return SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
-				.trustManager(InsecureTrustManagerFactory.INSTANCE);
+	private Http11SslContextSpec createSslContextSpec() {
+		return Http11SslContextSpec.forClient().configure(
+				(builder) -> builder.sslProvider(SslProvider.JDK).trustManager(InsecureTrustManagerFactory.INSTANCE));
 	}
 
 	/**

spring-boot-project/spring-boot-dependencies/build.gradle

@@ -1322,7 +1322,7 @@ bom {
 			]
 		}
 	}
-	library("Reactor Bom", "2020.0.5") {
+	library("Reactor Bom", "2020.0.6-SNAPSHOT") {
 		group("io.projectreactor") {
 			imports = [
 				"reactor-bom"

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/rsocket/netty/NettyRSocketServerFactory.java

@@ -31,6 +31,7 @@ import io.rsocket.transport.netty.server.TcpServerTransport;
 import io.rsocket.transport.netty.server.WebsocketServerTransport;
 import reactor.core.publisher.Mono;
 import reactor.netty.http.server.HttpServer;
+import reactor.netty.tcp.AbstractProtocolSslContextSpec;
 import reactor.netty.tcp.TcpServer;
 
 import org.springframework.boot.context.properties.PropertyMapper;
@@ -38,7 +39,6 @@ import org.springframework.boot.rsocket.server.ConfigurableRSocketServerFactory;
 import org.springframework.boot.rsocket.server.RSocketServer;
 import org.springframework.boot.rsocket.server.RSocketServerCustomizer;
 import org.springframework.boot.rsocket.server.RSocketServerFactory;
-import org.springframework.boot.web.embedded.netty.SslServerCustomizer;
 import org.springframework.boot.web.server.Ssl;
 import org.springframework.boot.web.server.SslStoreProvider;
 import org.springframework.http.client.reactive.ReactorResourceFactory;
@@ -171,12 +171,18 @@ public class NettyRSocketServerFactory implements RSocketServerFactory, Configur
 			httpServer = httpServer.runOn(this.resourceFactory.getLoopResources());
 		}
 		if (this.ssl != null && this.ssl.isEnabled()) {
-			SslServerCustomizer sslServerCustomizer = new SslServerCustomizer(this.ssl, null, this.sslStoreProvider);
-			httpServer = sslServerCustomizer.apply(httpServer);
+			httpServer = customizeSslConfiguration(httpServer);
 		}
 		return WebsocketServerTransport.create(httpServer.bindAddress(this::getListenAddress));
 	}
 
+	@SuppressWarnings("deprecation")
+	private HttpServer customizeSslConfiguration(HttpServer httpServer) {
+		org.springframework.boot.web.embedded.netty.SslServerCustomizer sslServerCustomizer = new org.springframework.boot.web.embedded.netty.SslServerCustomizer(
+				this.ssl, null, this.sslStoreProvider);
+		return sslServerCustomizer.apply(httpServer);
+	}
+
 	private ServerTransport<CloseableChannel> createTcpTransport() {
 		TcpServer tcpServer = TcpServer.create();
 		if (this.resourceFactory != null) {
@@ -196,19 +202,17 @@ public class NettyRSocketServerFactory implements RSocketServerFactory, Configur
 		return new InetSocketAddress(this.port);
 	}
 
-	private static final class TcpSslServerCustomizer extends SslServerCustomizer {
+	@SuppressWarnings("deprecation")
+	private static final class TcpSslServerCustomizer
+			extends org.springframework.boot.web.embedded.netty.SslServerCustomizer {
 
 		private TcpSslServerCustomizer(Ssl ssl, SslStoreProvider sslStoreProvider) {
 			super(ssl, null, sslStoreProvider);
 		}
 
 		private TcpServer apply(TcpServer server) {
-			try {
-				return server.secure((contextSpec) -> contextSpec.sslContext(getContextBuilder()));
-			}
-			catch (Exception ex) {
-				throw new IllegalStateException(ex);
-			}
+			AbstractProtocolSslContextSpec<?> sslContextSpec = createSslContextSpec();
+			return server.secure((spec) -> spec.sslContext(sslContextSpec));
 		}
 
 	}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/netty/NettyReactiveWebServerFactory.java

@@ -166,9 +166,7 @@ public class NettyReactiveWebServerFactory extends AbstractReactiveWebServerFact
 			server = server.bindAddress(this::getListenAddress);
 		}
 		if (getSsl() != null && getSsl().isEnabled()) {
-			SslServerCustomizer sslServerCustomizer = new SslServerCustomizer(getSsl(), getHttp2(),
-					getSslStoreProvider());
-			server = sslServerCustomizer.apply(server);
+			server = customizeSslConfiguration(server);
 		}
 		if (getCompression() != null && getCompression().getEnabled()) {
 			CompressionCustomizer compressionCustomizer = new CompressionCustomizer(getCompression());
@@ -178,6 +176,12 @@ public class NettyReactiveWebServerFactory extends AbstractReactiveWebServerFact
 		return applyCustomizers(server);
 	}
 
+	@SuppressWarnings("deprecation")
+	private HttpServer customizeSslConfiguration(HttpServer httpServer) {
+		SslServerCustomizer sslServerCustomizer = new SslServerCustomizer(getSsl(), getHttp2(), getSslStoreProvider());
+		return sslServerCustomizer.apply(httpServer);
+	}
+
 	private HttpProtocol[] listProtocols() {
 		if (getHttp2() != null && getHttp2().isEnabled() && getSsl() != null && getSsl().isEnabled()) {
 			return new HttpProtocol[] { HttpProtocol.H2, HttpProtocol.HTTP11 };

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/netty/SslServerCustomizer.java

@@ -38,9 +38,10 @@ import javax.net.ssl.TrustManagerFactory;
 import javax.net.ssl.X509ExtendedKeyManager;
 
 import io.netty.handler.ssl.ClientAuth;
-import io.netty.handler.ssl.SslContextBuilder;
+import reactor.netty.http.Http11SslContextSpec;
+import reactor.netty.http.Http2SslContextSpec;
 import reactor.netty.http.server.HttpServer;
-import reactor.netty.tcp.SslProvider;
+import reactor.netty.tcp.AbstractProtocolSslContextSpec;
 
 import org.springframework.boot.web.server.Http2;
 import org.springframework.boot.web.server.Ssl;
@@ -57,7 +58,9 @@ import org.springframework.util.ResourceUtils;
  * @author Raheela Aslam
  * @author Chris Bono
  * @since 2.0.0
+ * @deprecated this class is meant for Spring Boot internal use only.
  */
+@Deprecated
 public class SslServerCustomizer implements NettyServerCustomizer {
 
 	private final Ssl ssl;
@@ -74,22 +77,20 @@ public class SslServerCustomizer implements NettyServerCustomizer {
 
 	@Override
 	public HttpServer apply(HttpServer server) {
-		try {
-			return server.secure((contextSpec) -> {
-				SslProvider.DefaultConfigurationSpec spec = contextSpec.sslContext(getContextBuilder());
-				if (this.http2 != null && this.http2.isEnabled()) {
-					spec.defaultConfiguration(SslProvider.DefaultConfigurationType.H2);
+		AbstractProtocolSslContextSpec<?> sslContextSpec = createSslContextSpec();
+		return server.secure((spec) -> spec.sslContext(sslContextSpec));
 	}
-			});
-		}
-		catch (Exception ex) {
-			throw new IllegalStateException(ex);
+
+	protected AbstractProtocolSslContextSpec<?> createSslContextSpec() {
+		AbstractProtocolSslContextSpec<?> sslContextSpec;
+		if (this.http2 != null && this.http2.isEnabled()) {
+			sslContextSpec = Http2SslContextSpec.forServer(getKeyManagerFactory(this.ssl, this.sslStoreProvider));
 		}
+		else {
+			sslContextSpec = Http11SslContextSpec.forServer(getKeyManagerFactory(this.ssl, this.sslStoreProvider));
 		}
-
-	protected SslContextBuilder getContextBuilder() {
-		SslContextBuilder builder = SslContextBuilder.forServer(getKeyManagerFactory(this.ssl, this.sslStoreProvider))
-				.trustManager(getTrustManagerFactory(this.ssl, this.sslStoreProvider));
+		sslContextSpec.configure((builder) -> {
+			builder.trustManager(getTrustManagerFactory(this.ssl, this.sslStoreProvider));
 			if (this.ssl.getEnabledProtocols() != null) {
 				builder.protocols(this.ssl.getEnabledProtocols());
 			}
@@ -102,10 +103,11 @@ public class SslServerCustomizer implements NettyServerCustomizer {
 			else if (this.ssl.getClientAuth() == Ssl.ClientAuth.WANT) {
 				builder.clientAuth(ClientAuth.OPTIONAL);
 			}
-		return builder;
+		});
+		return sslContextSpec;
 	}
 
-	protected KeyManagerFactory getKeyManagerFactory(Ssl ssl, SslStoreProvider sslStoreProvider) {
+	KeyManagerFactory getKeyManagerFactory(Ssl ssl, SslStoreProvider sslStoreProvider) {
 		try {
 			KeyStore keyStore = getKeyStore(ssl, sslStoreProvider);
 			SslConfigurationValidator.validateKeyAlias(keyStore, ssl.getKeyAlias());
@@ -133,7 +135,7 @@ public class SslServerCustomizer implements NettyServerCustomizer {
 				ssl.getKeyStorePassword());
 	}
 
-	protected TrustManagerFactory getTrustManagerFactory(Ssl ssl, SslStoreProvider sslStoreProvider) {
+	TrustManagerFactory getTrustManagerFactory(Ssl ssl, SslStoreProvider sslStoreProvider) {
 		try {
 			KeyStore store = getTrustStore(ssl, sslStoreProvider);
 			TrustManagerFactory trustManagerFactory = TrustManagerFactory

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/rsocket/netty/NettyRSocketServerFactoryTests.java

@@ -22,7 +22,6 @@ import java.util.Arrays;
 import java.util.concurrent.Callable;
 
 import io.netty.buffer.PooledByteBufAllocator;
-import io.netty.handler.ssl.SslContextBuilder;
 import io.netty.handler.ssl.SslProvider;
 import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
 import io.rsocket.ConnectionSetupPayload;
@@ -37,6 +36,7 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.InOrder;
 import reactor.core.publisher.Mono;
+import reactor.netty.http.Http11SslContextSpec;
 import reactor.netty.http.client.HttpClient;
 import reactor.netty.tcp.TcpClient;
 import reactor.test.StepVerifier;
@@ -224,9 +224,9 @@ class NettyRSocketServerFactoryTests {
 
 	private HttpClient createSecureHttpClient() {
 		HttpClient httpClient = createHttpClient();
-		SslContextBuilder builder = SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
-				.trustManager(InsecureTrustManagerFactory.INSTANCE);
-		return httpClient.secure((spec) -> spec.sslContext(builder));
+		Http11SslContextSpec sslContextSpec = Http11SslContextSpec.forClient().configure(
+				(builder) -> builder.sslProvider(SslProvider.JDK).trustManager(InsecureTrustManagerFactory.INSTANCE));
+		return httpClient.secure((spec) -> spec.sslContext(sslContextSpec));
 	}
 
 	private HttpClient createHttpClient() {
@@ -237,9 +237,9 @@ class NettyRSocketServerFactoryTests {
 
 	private TcpClient createSecureTcpClient() {
 		TcpClient tcpClient = createTcpClient();
-		SslContextBuilder builder = SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
-				.trustManager(InsecureTrustManagerFactory.INSTANCE);
-		return tcpClient.secure((spec) -> spec.sslContext(builder));
+		Http11SslContextSpec sslContextSpec = Http11SslContextSpec.forClient().configure(
+				(builder) -> builder.sslProvider(SslProvider.JDK).trustManager(InsecureTrustManagerFactory.INSTANCE));
+		return tcpClient.secure((spec) -> spec.sslContext(sslContextSpec));
 	}
 
 	private TcpClient createTcpClient() {

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/netty/SslServerCustomizerTests.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,6 +31,7 @@ import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
  * @author Andy Wilkinson
  * @author Raheela Aslam
  */
+@SuppressWarnings("deprecation")
 class SslServerCustomizerTests {
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/reactive/server/AbstractReactiveWebServerFactoryTests.java

@@ -37,7 +37,6 @@ import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.handler.codec.http.HttpHeaderNames;
 import io.netty.handler.codec.http.HttpResponse;
-import io.netty.handler.ssl.SslContextBuilder;
 import io.netty.handler.ssl.SslProvider;
 import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
 import org.assertj.core.api.ThrowableAssert.ThrowingCallable;
@@ -47,6 +46,7 @@ import org.junit.jupiter.api.Test;
 import reactor.core.publisher.Mono;
 import reactor.core.publisher.Sinks;
 import reactor.netty.NettyPipeline;
+import reactor.netty.http.Http11SslContextSpec;
 import reactor.netty.http.client.HttpClient;
 import reactor.test.StepVerifier;
 
@@ -195,10 +195,9 @@ public abstract class AbstractReactiveWebServerFactoryTests {
 	}
 
 	protected ReactorClientHttpConnector buildTrustAllSslConnector() {
-		SslContextBuilder builder = SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
-				.trustManager(InsecureTrustManagerFactory.INSTANCE);
-		HttpClient client = HttpClient.create().wiretap(true)
-				.secure((sslContextSpec) -> sslContextSpec.sslContext(builder));
+		Http11SslContextSpec sslContextSpec = Http11SslContextSpec.forClient().configure(
+				(builder) -> builder.sslProvider(SslProvider.JDK).trustManager(InsecureTrustManagerFactory.INSTANCE));
+		HttpClient client = HttpClient.create().wiretap(true).secure((spec) -> spec.sslContext(sslContextSpec));
 		return new ReactorClientHttpConnector(client);
 	}
 
@@ -232,10 +231,11 @@ public abstract class AbstractReactiveWebServerFactoryTests {
 		KeyManagerFactory clientKeyManagerFactory = KeyManagerFactory
 				.getInstance(KeyManagerFactory.getDefaultAlgorithm());
 		clientKeyManagerFactory.init(clientKeyStore, "password".toCharArray());
-		SslContextBuilder builder = SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
-				.trustManager(InsecureTrustManagerFactory.INSTANCE).keyManager(clientKeyManagerFactory);
-		HttpClient client = HttpClient.create().wiretap(true)
-				.secure((sslContextSpec) -> sslContextSpec.sslContext(builder));
+
+		Http11SslContextSpec sslContextSpec = Http11SslContextSpec.forClient()
+				.configure((builder) -> builder.sslProvider(SslProvider.JDK)
+						.trustManager(InsecureTrustManagerFactory.INSTANCE).keyManager(clientKeyManagerFactory));
+		HttpClient client = HttpClient.create().wiretap(true).secure((spec) -> spec.sslContext(sslContextSpec));
 		return new ReactorClientHttpConnector(client);
 	}