Server HTTPS Support
Akka HTTP supports TLS encryption on the server-side as well as on the client-side.
The central vehicle for configuring encryption is the HttpsConnectionContext
HttpsConnectionContext
, which can be created using the static method ConnectionContext.https
which is defined like this:
- Scala
-
source
def https( sslContext: SSLContext, sslConfig: Option[AkkaSSLConfig] = None, enabledCipherSuites: Option[immutable.Seq[String]] = None, enabledProtocols: Option[immutable.Seq[String]] = None, clientAuth: Option[TLSClientAuth] = None, sslParameters: Option[SSLParameters] = None) = new HttpsConnectionContext(sslContext, sslConfig, enabledCipherSuites, enabledProtocols, clientAuth, sslParameters)
- Java
-
source
// ConnectionContext /** Used to serve HTTPS traffic. */ def https(sslContext: SSLContext): HttpsConnectionContext = // ... /** Used to serve HTTPS traffic. */ def https( sslContext: SSLContext, sslConfig: Optional[AkkaSSLConfig], enabledCipherSuites: Optional[JCollection[String]], enabledProtocols: Optional[JCollection[String]], clientAuth: Optional[TLSClientAuth], sslParameters: Optional[SSLParameters]) = // ...
On the server-side the bind
, and bindAndHandleXXX
methods of the Http
Http
extension define an optional httpsContext
parameter, which can receive the HTTPS configuration in the form of an HttpsContext
instance. If defined encryption is enabled on all accepted connections. Otherwise it is disabled (which is the default).
For detailed documentation for client-side HTTPS support refer to Client-Side HTTPS Support.
Obtaining SSL/TLS Certificates
In order to run an HTTPS server a certificate has to be provided, which usually is either obtained from a signing authority or created by yourself for local or staging environment purposes.
Signing authorities often provide instructions on how to create a Java keystore (typically with reference to Tomcat configuration). If you want to generate your own certificates, the official Oracle documentation on how to generate keystores using the JDK keytool utility can be found here.
SSL-Config provides a more targeted guide on generating certificates, so we recommend you start with the guide titled Generating X.509 Certificates.
Using HTTPS
Once you have obtained the server certificate, using it is as simple as preparing an HttpsConnectionContext
HttpsConnectionContext
and either setting it as the default one to be used by all servers started by the given Http
Http
extension or passing it in explicitly when binding the server.
The below example shows how setting up HTTPS works. First, you create and configure an instance of HttpsConnectionContext
HttpsConnectionContext
:
- Scala
-
source
import java.io.InputStream import java.security.{ SecureRandom, KeyStore } import javax.net.ssl.{ SSLContext, TrustManagerFactory, KeyManagerFactory } import akka.actor.ActorSystem import akka.http.scaladsl.server.{ Route, Directives } import akka.http.scaladsl.{ ConnectionContext, HttpsConnectionContext, Http } import akka.stream.ActorMaterializer import com.typesafe.sslconfig.akka.AkkaSSLConfig implicit val system = ActorSystem() implicit val mat = ActorMaterializer() implicit val dispatcher = system.dispatcher // Manual HTTPS configuration val password: Array[Char] = "change me".toCharArray // do not store passwords in code, read them from somewhere safe! val ks: KeyStore = KeyStore.getInstance("PKCS12") val keystore: InputStream = getClass.getClassLoader.getResourceAsStream("server.p12") require(keystore != null, "Keystore required!") ks.load(keystore, password) val keyManagerFactory: KeyManagerFactory = KeyManagerFactory.getInstance("SunX509") keyManagerFactory.init(ks, password) val tmf: TrustManagerFactory = TrustManagerFactory.getInstance("SunX509") tmf.init(ks) val sslContext: SSLContext = SSLContext.getInstance("TLS") sslContext.init(keyManagerFactory.getKeyManagers, tmf.getTrustManagers, new SecureRandom) val https: HttpsConnectionContext = ConnectionContext.https(sslContext)
- Java
-
source
import javax.net.ssl.KeyManagerFactory; import javax.net.ssl.SSLContext; import javax.net.ssl.TrustManagerFactory; import java.io.IOException; import java.io.InputStream; import java.security.*; import java.security.cert.CertificateException; import akka.http.javadsl.HttpsConnectionContext; // ** CONFIGURING ADDITIONAL SETTINGS ** // public static HttpsConnectionContext useHttps(ActorSystem system) { HttpsConnectionContext https = null; try { // initialise the keystore // !!! never put passwords into code !!! final char[] password = new char[]{'a', 'b', 'c', 'd', 'e', 'f'}; final KeyStore ks = KeyStore.getInstance("PKCS12"); final InputStream keystore = SimpleServerApp.class.getClassLoader().getResourceAsStream("httpsDemoKeys/keys/server.p12"); if (keystore == null) { throw new RuntimeException("Keystore required!"); } ks.load(keystore, password); final KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("SunX509"); keyManagerFactory.init(ks, password); final TrustManagerFactory tmf = TrustManagerFactory.getInstance("SunX509"); tmf.init(ks); final SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(keyManagerFactory.getKeyManagers(), tmf.getTrustManagers(), new SecureRandom()); https = ConnectionContext.https(sslContext); } catch (NoSuchAlgorithmException | KeyManagementException e) { system.log().error("Exception while configuring HTTPS.", e); } catch (CertificateException | KeyStoreException | UnrecoverableKeyException | IOException e) { system.log().error("Exception while ", e); } return https; }
Once you configured the HTTPS context, you can set it as default: Then pass it to the akka.http.javadsl.Http
class’s setDefaultServerHttpContext
method, like in the below main
method.
- Scala
-
source
// sets default context to HTTPS – all Http() bound servers for this ActorSystem will use HTTPS from now on Http().setDefaultServerHttpContext(https) Http().bindAndHandle(routes, "127.0.0.1", 9090, connectionContext = https)
- Java
-
source
public Route multiply(int x, int y) { int result = x * y; return complete(String.format("%d * %d = %d", x, y, result)); } public CompletionStage<Route> multiplyAsync(Executor ctx, int x, int y) { return CompletableFuture.supplyAsync(() -> multiply(x, y), ctx); } public Route createRoute() { Route addHandler = parameter(StringUnmarshallers.INTEGER, "x", x -> parameter(StringUnmarshallers.INTEGER, "y", y -> { int result = x + y; return complete(String.format("%d + %d = %d", x, y, result)); }) ); BiFunction<Integer, Integer, Route> subtractHandler = (x, y) -> { int result = x - y; return complete(String.format("%d - %d = %d", x, y, result)); }; return concat( // matches the empty path pathSingleSlash(() -> getFromResource("web/calculator.html") ), // matches paths like this: /add?x=42&y=23 path("add", () -> addHandler), path("subtract", () -> parameter(StringUnmarshallers.INTEGER, "x", x -> parameter(StringUnmarshallers.INTEGER, "y", y -> subtractHandler.apply(x, y) ) ) ), // matches paths like this: /multiply/{x}/{y} path(PathMatchers.segment("multiply").slash(integerSegment()).slash(integerSegment()), this::multiply ), path(PathMatchers.segment("multiplyAsync").slash(integerSegment()).slash(integerSegment()), (x, y) -> extractExecutionContext(ctx -> onSuccess(multiplyAsync(ctx, x, y), Function.identity()) ) ), post(() -> path("hello", () -> entity(entityToString(), body -> complete("Hello " + body + "!") ) ) ) ); } // ** STARTING THE SERVER ** // public static void main(String[] args) throws IOException { final ActorSystem system = ActorSystem.create("SimpleServerApp"); final ActorMaterializer materializer = ActorMaterializer.create(system); final Http http = Http.get(system); boolean useHttps = false; // pick value from anywhere if ( useHttps ) { HttpsConnectionContext https = useHttps(system); http.setDefaultServerHttpContext(https); } final SimpleServerApp app = new SimpleServerApp(); final Flow<HttpRequest, HttpResponse, NotUsed> flow = app.createRoute().flow(system, materializer); Http.get(system).bindAndHandle(flow, ConnectHttp.toHost("localhost", 8080), materializer); System.out.println("Type RETURN to exit"); System.in.read(); system.terminate(); }
It is also possible to pass in the context to specific bind...
(or client) calls, like displayed below:
sourceHttp().bind("127.0.0.1", connectionContext = https)
// or using the high level routing DSL:
val routes: Route = get { complete("Hello world!") }
Http().bindAndHandle(routes, "127.0.0.1", 8080, connectionContext = https)
Running both HTTP and HTTPS
If you want to run HTTP and HTTPS servers in a single application, you can call bind...
methods twice, one for HTTPS, and the other for HTTP.
When configuring HTTPS, you can do it up like explained in the above Using HTTPS section,
- Scala
-
source
implicit val system = ActorSystem() implicit val mat = ActorMaterializer() implicit val dispatcher = system.dispatcher // Manual HTTPS configuration val password: Array[Char] = "change me".toCharArray // do not store passwords in code, read them from somewhere safe! val ks: KeyStore = KeyStore.getInstance("PKCS12") val keystore: InputStream = getClass.getClassLoader.getResourceAsStream("server.p12") require(keystore != null, "Keystore required!") ks.load(keystore, password) val keyManagerFactory: KeyManagerFactory = KeyManagerFactory.getInstance("SunX509") keyManagerFactory.init(ks, password) val tmf: TrustManagerFactory = TrustManagerFactory.getInstance("SunX509") tmf.init(ks) val sslContext: SSLContext = SSLContext.getInstance("TLS") sslContext.init(keyManagerFactory.getKeyManagers, tmf.getTrustManagers, new SecureRandom) val https: HttpsConnectionContext = ConnectionContext.https(sslContext)
- Java
-
source
import javax.net.ssl.KeyManagerFactory; import javax.net.ssl.SSLContext; import javax.net.ssl.TrustManagerFactory; import java.io.IOException; import java.io.InputStream; import java.security.*; import java.security.cert.CertificateException; import akka.http.javadsl.HttpsConnectionContext; // ** CONFIGURING ADDITIONAL SETTINGS ** // public static HttpsConnectionContext useHttps(ActorSystem system) { HttpsConnectionContext https = null; try { // initialise the keystore // !!! never put passwords into code !!! final char[] password = new char[]{'a', 'b', 'c', 'd', 'e', 'f'}; final KeyStore ks = KeyStore.getInstance("PKCS12"); final InputStream keystore = SimpleServerApp.class.getClassLoader().getResourceAsStream("httpsDemoKeys/keys/server.p12"); if (keystore == null) { throw new RuntimeException("Keystore required!"); } ks.load(keystore, password); final KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("SunX509"); keyManagerFactory.init(ks, password); final TrustManagerFactory tmf = TrustManagerFactory.getInstance("SunX509"); tmf.init(ks); final SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(keyManagerFactory.getKeyManagers(), tmf.getTrustManagers(), new SecureRandom()); https = ConnectionContext.https(sslContext); } catch (NoSuchAlgorithmException | KeyManagementException e) { system.log().error("Exception while configuring HTTPS.", e); } catch (CertificateException | KeyStoreException | UnrecoverableKeyException | IOException e) { system.log().error("Exception while ", e); } return https; }
Then, call bind...
methods twice like below. The passed https
context is from the above code snippet. SimpleServerApp.useHttps(system)
is calling the above defined public static HttpsConnectionContext useHttps(ActorSystem system)
method.
- Scala
-
source
// you can run both HTTP and HTTPS in the same application as follows: val commonRoutes: Route = get { complete("Hello world!") } Http().bindAndHandle(commonRoutes, "127.0.0.1", 443, connectionContext = https) Http().bindAndHandle(commonRoutes, "127.0.0.1", 80)
- Java
-
source
final Http http = Http.get(system); //Run HTTP server firstly http.bindAndHandle(flow, ConnectHttp.toHost("localhost", 80), materializer); //get configured HTTPS context HttpsConnectionContext https = SimpleServerApp.useHttps(system); // sets default context to HTTPS – all Http() bound servers for this ActorSystem will use HTTPS from now on http.setDefaultServerHttpContext(https); //Then run HTTPS server http.bindAndHandle(flow, ConnectHttp.toHost("localhost", 443), materializer);
Mutual authentication
To require clients to authenticate themselves when connecting, pass in Some(TLSClientAuth.Need)
Optional.of(TLSClientAuth.need)
as the clientAuth
parameter of the HttpsConnectionContext
HttpsConnectionContext
and make sure the truststore is populated accordingly. For further (custom) certificate checks you can use the `Tls-Session-Info`
`TlsSessionInfo`
synthetic header.
At this point dynamic renegotiation of the certificates to be used is not implemented. For details see issue #18351 and some preliminary work in PR #19787.
Further reading
The topic of properly configuring HTTPS for your web server is an always changing one, thus we recommend staying up to date with various security breach news and of course keep your JVM at the latest version possible, as the default settings are often updated by Oracle in reaction to various security updates and known issues.
We also recommend having a look at the Play documentation about securing your app, as well as the techniques described in the Play documentation about setting up a reverse proxy to terminate TLS in front of your application instead of terminating TLS inside the JVM, and therefore Akka HTTP, itself.
Other excellent articles on the subject: