Apache camel SSL connection to restful service - apache

Question

I am busy with a project where I have to do a GET on an exposed rest service using specific certificates. I am using the apache camel framework with the https4 component. I created a keystore and tested it using soapUI and it connected successfully, but I am however unable to connect through my project.
I used the following page as reference: http://camel.apache.org/http4.html
I set up the SSL for the HTTP Client through the following configuration:
<spring:sslContextParameters id="sslContextParameters">
<spring:keyManagers keyPassword="xxxx">
<spring:keyStore resource="classpath:certificates/keystore.jks" password="xxxx"/>
</spring:keyManagers>
</spring:sslContextParameters>
<setHeader headerName="CamelHttpMethod">
<simple>GET</simple>
</setHeader>
My endpoint is configured as:
<to uri="https4://endpointUrl:9007/v1/{id}?sslContextParametersRef=sslContextParameters"/>
The stacktrace I am receiving:
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1904)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:279)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:273)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1446)
at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:209)
at sun.security.ssl.Handshaker.processLoop(Handshaker.java:901)
at sun.security.ssl.Handshaker.process_record(Handshaker.java:837)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1023)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1332)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1359)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1343)
at org.apache.http.conn.ssl.SSLConnectionSocketFactory.createLayeredSocket(SSLConnectionSocketFactory.java:394)
at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:353)
at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:141)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:353)
at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:380)
at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:236)
at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:184)
at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:88)
at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110)
at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:55)
at org.apache.camel.component.http4.HttpProducer.executeMethod(HttpProducer.java:301)
at org.apache.camel.component.http4.HttpProducer.process(HttpProducer.java:173)
at org.apache.camel.util.AsyncProcessorConverterHelper$ProcessorToAsyncProcessorBridge.process(AsyncProcessorConverterHelper.java:61)
at org.apache.camel.processor.SendProcessor.process(SendProcessor.java:145)
at org.apache.camel.processor.interceptor.TraceInterceptor.process(TraceInterceptor.java:163)
at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:468)
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197)
at org.apache.camel.processor.Pipeline.process(Pipeline.java:121)
at org.apache.camel.processor.Pipeline.process(Pipeline.java:83)
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197)
at org.apache.camel.component.direct.DirectProducer.process(DirectProducer.java:62)
at org.apache.camel.impl.InterceptSendToEndpoint$1.process(InterceptSendToEndpoint.java:164)
at org.apache.camel.processor.SendProcessor.process(SendProcessor.java:145)
at org.apache.camel.processor.interceptor.TraceInterceptor.process(TraceInterceptor.java:163)
at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:468)
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197)
at org.apache.camel.processor.ChoiceProcessor.process(ChoiceProcessor.java:117)
at org.apache.camel.processor.interceptor.TraceInterceptor.process(TraceInterceptor.java:163)
at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:468)
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197)
at org.apache.camel.processor.Pipeline.process(Pipeline.java:121)
at org.apache.camel.processor.Pipeline.access$100(Pipeline.java:44)
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:139)
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:257)
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:480)
at org.apache.camel.processor.interceptor.TraceInterceptor$1.done(TraceInterceptor.java:180)
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:155)
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:257)
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:148)
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:257)
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:480)
at org.apache.camel.processor.interceptor.TraceInterceptor$1.done(TraceInterceptor.java:180)
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:155)
at org.apache.camel.component.cxf.CxfClientCallback.handleResponse(CxfClientCallback.java:61)
at org.apache.cxf.endpoint.ClientImpl.onMessage(ClientImpl.java:827)
at org.apache.cxf.transport.http.HTTPConduit$WrappedOutputStream.handleResponseInternal(HTTPConduit.java:1672)
at org.apache.cxf.transport.http.HTTPConduit$WrappedOutputStream$1.run(HTTPConduit.java:1168)
at org.apache.cxf.workqueue.AutomaticWorkQueueImpl$3.run(AutomaticWorkQueueImpl.java:428)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.cxf.workqueue.AutomaticWorkQueueImpl$AWQThreadFactory$1.run(AutomaticWorkQueueImpl.java:353)
at java.lang.Thread.run(Thread.java:745)
Any help would be much appreciated !

Answer 1

Just same: I followed documented instructions and got too stuck on "PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target". There's a quick fix, but if you want to link the configuration to the client HTTP session at stake, it becomes a complex set-up.
Method 1:
Doc pages, forums, and this other article would tell you that setting JVM launch options "-Djavax.net.ssl.trustStore=myKeystore.jks -Djavax.net.ssl.trustStorePassword=mystorepass" do solve the issue, provided the remote parties' certificates (self signed, or signed by a CA but then with all the full certificate chain) were all fetched as Trusted certificates in the supplied keystore. Fact is, HTTP4 is based on JSSE, and these java launch options do configure the stack JVM-wide.
As an alternative, you can also fetch peers' certificates (complete chains) in the default JVM keystore jre\lib\security\cacerts (initial password: "changeit") and thus not even need JVM options.
If you have a few outgoing client connections and few peer certificates, this is the simplest way.
Method 2:
In our context, with above 100 remote parties, each requiring certificate updates every 2 years in average, that method implies a JVM reboot on an updated keystore about every week. Our highly available gateway is no longer highly available. So I searched a dynamic/per-connexion/programmatic way.
Below is a simplified excerpt of code from a CAMEL Processor that we use to remotely connect as REST or plain-vanilla HTTP client, with or without SSL/TLS, and with or without client-side certificate (i.e. 2-way SSL/TLS versus 1-way SSL/TLS), as well as combine HTTP Basic Auth as required by peers.
For various reasons the now old CAMEL version 2.16.3 is still used in our context. I have not tested yet newer versions. I suspect no changes given the libraries at stake under the Apache CAMEL layer.
I have added in the code below many comments detailling variant API's to the same effect. So you have clues below to further simplify the code or try alternatives with newer HTTP4 versions. As is, the code works with 2.16, as a CAMEL Processor bean within a Spring application context that contains the entire CAMEL route definition in DSL.
In our context we use java code for configuring entirely dynamic SSL/TLS outbound connexions per session. You should have no difficulties freezing part of the configuration that we set below dynamically via java, into the CAMEL XML DSL as suitable to your context.
Maven dependencies at stake:
<properties>
<camel-version>2.16.3</camel-version>
</properties>
...
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-core</artifactId>
<version>${camel-version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-http4</artifactId>
<version>${camel-version}</version>
<scope>provided</scope>
</dependency>
Code extracted from our org.apache.camel.Processor (I have removed many Exception handling and simplified the code below in order to focus on the solution):
// relevant imports (partial)
import java.security.KeyStore;
import java.security.SecureRandom;
import java.security.Security;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;
import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.component.http4.HttpClientConfigurer;
import org.apache.camel.component.http4.HttpComponent;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.HttpClientConnectionManager;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.conn.BasicHttpClientConnectionManager;
...
#Override
public void process(Exchange exchange) throws Exception {
// assume here that we have previously fetched all dynamic connexion parameters in set of java Properties. Of course you can use numerous means to inject connection parameters
Properties params= ... ;
// Trick! 'targetURL' is the URI of the http server to call. Its not the same as the Camel endpoint URI (see further "httpUrlToken" placeHolder), on which you configure endpoint options
// Fact is, we prefer to pass just the target URL as parameter and keep full control on building the CAMEL endpoint URI in java
String targetURL= params.getProperty("targetURL"); // URL to call, e.g. "http://remoteHost.com/some/servlet/path". Will override the placeholder URL set on the endpoint.
// default plain HTTP without SSL/TLS:
String endPointURI = "http4://httpUrlToken?throwExceptionOnFailure=false"; // with option to prevent exceptions from being thrown for failed response codes. It allows us to process all the response codes in a response Processor
// Oh yes! we have to manage a map of HttpComponent instances, because the CAMEL doc clearly tells that each instance can only support a single configuration
// and our true connector is multithreading where each request may go to a different (dynamic) destination with different SSL settings,
// so we actually use a Map of HttpComponent instances of size MAX_THREADS and indexed by the thread ID plus ageing and re-use strategies... but this brings us too far.
// So, for a single thread per client instance, you can just do:
HttpComponent httpComponent = exchange.getContext().getComponent("http4", HttpComponent.class);
// overload in case of SSL/TLS
if (targetURL.startsWith("https")) {
try {
endPointURI = "https4://httpUrlToken?throwExceptionOnFailure=false";
httpComponent = exchange.getContext().getComponent("https4", HttpComponent.class); // well: "https4" and "http4" are the same, so you may skip this line! (our true HttpComponent map is common to secured and unsecured client connexions)
// basic SSL context setup as documented elsewhere, should be enough in theory
SSLContext sslctxt = getSSLContext(exchange, params.getProperty("keystoreFilePath"), params.getProperty("keystorePassword"), params.getProperty("authenticationMode")); // cfr helper method below
HttpClientConfigurer httpClientConfig = getEndpointClientConfigurer(sslctxt); // cfr helper method below
httpComponent.setHttpClientConfigurer(httpClientConfig);
// from here, if you skip the rest of the configuration, you'll get the exception "sun.security.provider.certpath.SunCertPathBuilderException:unable to find valid certification path to requested target"
// the SSL context covers certificate validation but not the host name verification process
// we de-activate here at the connection factory level (systematically... you may not want that), and link the later to the HTTP component
HostnameVerifier hnv = new AllowAll();
SSLConnectionSocketFactory sslSocketFactory = new SSLConnectionSocketFactory(sslctxt, hnv);
// You may choose to enforce the BasicHttpClientConnectionManager or PoolingHttpClientConnectionManager, cfr CAMEL docs
// In addition, the following linkage of the connection factory through a Registry that captures the 'https' scheme to your factory is required
Registry<ConnectionSocketFactory> lookup = RegistryBuilder.<ConnectionSocketFactory>create().register("https", sslSocketFactory).build();
HttpClientConnectionManager connManager = new BasicHttpClientConnectionManager(lookup);
// Does not work in 2.16, as documented at http://camel.apache.org/http4.html#HTTP4-UsingtheJSSEConfigurationUtility
// ... keystore and key manager setup ...
// SSLContextParameters scp = new SSLContextParameters();
// scp.setKeyManagers(...);
// httpComponent.setSslContextParameters(scp);
// Not as good as using a connection manager on the HTTP component, although same effects in theory
// HttpClientBuilder clientBuilder = HttpClientBuilder.create();
// clientBuilder.set... various parameters...
// httpClientConfig.configureHttpClient(clientBuilder);
// Commented-out alternative method to set BasicAuth with user and password
// HttpConfiguration httpConfiguration = new HttpConfiguration();
// httpConfiguration.setAuthUsername(authUsername);
// ... more settings ...
// httpComponent.setHttpConfiguration(httpConfiguration);
// setClientConnectionManager() is compulsory to prevent "SunCertPathBuilderException: unable to find valid certification path to requested target"
// if instead we bind the connection manager to a clientBuilder, that doesn't work...
httpComponent.setClientConnectionManager(connManager);
} catch (Exception e) { ... ; }
}
// (back to code common to secured and unsecured client sessions)
// additional parameters on the endpoint as needed, cfr API docs
httpComponent.set...(...) ;
// you may want to append these 3 URI options in case of HTTP[S] with Basic Auth
if (... basic Auth needed ...)
endPointURI += "&authUsername="+params.getProperty("user")+"&authPassword="+params.getProperty("password")+"&authenticationPreemptive=true";
// *********** ACTUAL TRANSMISSION ********************
exchange.getIn().setHeader(Exchange.HTTP_URI, targetURL); // needed to overload the "httpUrlToken" placeholder in the endPointURI
// Next, there are many ways to get a CAMEL Producer or ProducerTemplate
// e.g. httpComponent.createEndpoint(endPointURI).createProducer()
// ... in our case we use a template injected from a Spring application context (i.e. <camel:template id="producerTemplate"/>) via constructor arguments on our Processor bean
try {
producerTemplate.send(httpComponent.createEndpoint(endPointURI),exchange);
} catch (Exception e) { ...; }
// you can then process the HTTP response here, or better dedicate the next
// Processor on the CAMEL route to such handlings...
...
}
Supporting helper methods, invoked by above code
private HttpClientConfigurer getEndpointClientConfigurer(final SSLContext sslContext) {
return new HttpClientConfigurer(){
#Override
public void configureHttpClient(HttpClientBuilder clientBuilder) {
// I put a logger trace here to see if/when the ssl context is actually applied, the outcome was ... weird, try it!
clientBuilder.setSSLContext(sslContext);
}
};
}
/**
* Build a SSL context with keystore and other parameters according to authentication mode.
* The keystore may just contain a trusted peer's certificate for 1way cases, and the associated certificate chain up to a trusted root as applicable.
* The keystore shall too contain one single client private key and certificate for 2way modes. We assume here a same password on keystore and private key.
* #param authenticationMode one of "1waySSL" "1wayTLS" "2waySSL" "2wayTLS" each possibly suffixed by "noCHECK" as in "1waySSLnoCHECK"
* #param keystoreFilePath can be null for "noCHECK" modes
* #param keystorePassword would be null if above is null
*/
private SSLContext getSSLContext(Exchange exchange, String keystoreFilePath, String keystorePassword, String authenticationMode) throws GeneralSecurityException, FileNotFoundException, IOException {
SSLContext sslContext = SSLContext.getInstance(authenticationMode.substring(4,7).toUpperCase(),"SunJSSE");
//enforce Trust ALL ? pass a trust manager that does not validate certificate chains
if (authenticationMode.endsWith("noCHECK")) {
TrustManager[] trustAllCerts = new TrustManager[]{ new TrustALLManager()};
sslContext.init(null , trustAllCerts, null);
return sslContext;
}
// we use https, and validate remote cert's by default, henceforth keystore and password become compulsory
if (null == keystoreFilePath || null == keystorePassword)
throw new GeneralSecurityException("Config ERROR: using https://... and implicit default AUTHMODE=1waySSL altogether requires to supply keystore parameters");
KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
TrustManagerFactory tmf = TrustManagerFactory.getInstance("SunX509");
trustStore.load(new FileInputStream(keystoreFilePath), keystorePassword.toCharArray());
tmf.init(trustStore);
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
if (authenticationMode.charAt(0)=='2') { // our authenticationMode starts with 1way.. or 2way...
// 2way... case: set the keystore parameters accordingly
keyStore.load(new FileInputStream(keystoreFilePath), keystorePassword.toCharArray());
kmf.init(keyStore, keystorePassword.toCharArray());
sslContext.init(kmf.getKeyManagers() , tmf.getTrustManagers(), new SecureRandom());
} else { // 1way... case
sslContext.init(null , tmf.getTrustManagers(), new SecureRandom());
}
return sslContext;
}
// Create a trust manager that does not validate certificate chains
private class TrustALLManager implements X509TrustManager {
#Override
public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException { }
#Override
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException { }
#Override
public X509Certificate[] getAcceptedIssuers() {
return new X509Certificate[0];
}
}
private static class AllowAll implements HostnameVerifier
{
#Override
public boolean verify(String arg0, SSLSession arg1) {
return true;
}
}
}
Hope this helps. I spent many hours trying to get it working (although I know well about SSL/TLS principles, security, X509, etc) ... This code is far from my taste for clean and lean java code. In addition I assumed that you do know how to build a keystore, supply all needed certificate chains, define a CAMEL route, etc. As such, it works with Camel 2.16 within a Spring Application Context, and has no other pretention than providing clues that would save you hours.