Monday, July 6, 2009

Processing SAML in Java using OpenSAML

I'm currently doing all of my SAML 2.0 work in a .NET environment, but I wanted to verify my SAML in Java too so I created this tester utilizing OpenSAML. It certainly isn't pretty at this point, and I'm certainly not saying it represents any best-practices, but I'm going to post it in its current state because I think it illustrates some useful things. It's basically just unmarshalling xml to an OpenSAML response object, verifying the signature on the response, and decrypting an assertion. Nothing terribly mind-blowing, but it might prove useful to someone.

import org.w3c.dom.Document;
import org.w3c.dom.Element;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;

import java.util.List;

import javax.xml.namespace.QName;
import javax.xml.validation.Schema;

import java.security.KeyFactory;
import java.security.KeyStore;
import java.security.PublicKey;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.security.interfaces.RSAPrivateKey;
import java.security.spec.X509EncodedKeySpec;

import org.opensaml.DefaultBootstrap;
import org.opensaml.common.xml.SAMLSchemaBuilder;
import org.opensaml.saml2.core.Assertion;
import org.opensaml.saml2.core.Attribute;
import org.opensaml.saml2.core.AttributeStatement;
import org.opensaml.saml2.core.Response;
import org.opensaml.saml2.encryption.Decrypter;
import org.opensaml.xml.Configuration;
import org.opensaml.xml.XMLObject;
import org.opensaml.xml.encryption.DecryptionException;
import org.opensaml.xml.encryption.InlineEncryptedKeyResolver;
import org.opensaml.xml.io.Unmarshaller;
import org.opensaml.xml.parse.BasicParserPool;
import org.opensaml.xml.security.keyinfo.StaticKeyInfoCredentialResolver;
import org.opensaml.xml.security.x509.BasicX509Credential;
import org.opensaml.xml.signature.Signature;
import org.opensaml.xml.signature.SignatureValidator;
import org.opensaml.xml.validation.ValidationException;


public class Tester
{
public static void main(String[] args)
{
try
{
//initialize the opensaml library
DefaultBootstrap.bootstrap();

Schema schema = SAMLSchemaBuilder.getSAML11Schema();

//get parser pool manager
BasicParserPool parserPoolManager = new BasicParserPool();
parserPoolManager.setNamespaceAware(true);
parserPoolManager.setIgnoreElementContentWhitespace(true);
parserPoolManager.setSchema(schema);

//grab the xml file
File xmlFile = new File("C:\\Documents and Settings\\kgellis\\My Documents\\Eclipse\\Workspace\\MyOpenSamlTester\\Files\\Raw_AssertionEncrypted.xml");

//parse xml file
FileInputStream fileInputStream = new FileInputStream(xmlFile);
InputStream inputStream = fileInputStream;
Document document = parserPoolManager.parse(inputStream);
Element metadataRoot = document.getDocumentElement();

QName qName= new QName(metadataRoot.getNamespaceURI(), metadataRoot.getLocalName(), metadataRoot.getPrefix());

//get an unmarshaller
Unmarshaller unmarshaller = Configuration.getUnmarshallerFactory().getUnmarshaller(qName);

//unmarshall using the document root element
Response response = (Response)unmarshaller.unmarshall(metadataRoot);

//we have the xml unmarshalled to a response object
System.out.println("Response object created");
System.out.println("Issue Instant: " + response.getIssueInstant().toString());
System.out.println("Signature Reference ID: " + response.getSignatureReferenceID().toString());

//grab the certificate file
File certificateFile = new File("C:\\Documents and Settings\\kgellis\\My Documents\\Eclipse\\Workspace\\MyOpenSamlTester\\Files\\Con-wayPublicKey.cer");

//get the certificate from the file
InputStream inputStream2 = new FileInputStream(certificateFile);
CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
X509Certificate certificate = (X509Certificate)certificateFactory.generateCertificate(inputStream2);
inputStream2.close();

//pull out the public key part of the certificate into a KeySpec
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(certificate.getPublicKey().getEncoded());

//get KeyFactory object that creates key objects, specifying RSA
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
System.out.println("Security Provider: " + keyFactory.getProvider().toString());

//generate public key to validate signatures
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);

//we have the public key
System.out.println("Public Key created");

//create credentials
BasicX509Credential publicCredential = new BasicX509Credential();

//add public key value
publicCredential.setPublicKey(publicKey);

//create SignatureValidator
SignatureValidator signatureValidator = new SignatureValidator(publicCredential);

//get the signature to validate from the response object
Signature signature = response.getSignature();

//try to validate
try
{
signatureValidator.validate(signature);
}
catch (ValidationException ve)
{
System.out.println("Signature is NOT valid.");
System.out.println(ve.getMessage());
return;
}

//no validation exception was thrown
System.out.println("Signature is valid.");

//start decryption of assertion

//grab the KeyStore file
File keyStoreFile = new File("C:\\Documents and Settings\\kgellis\\My Documents\\Eclipse\\Workspace\\MyOpenSamlTester\\Files\\WWCPrivateKey.jks");

KeyStore keyStore = KeyStore.getInstance("JKS");

//load up a KeyStore
keyStore.load(new FileInputStream(keyStoreFile), "!c3c0ld".toCharArray());

RSAPrivateKey privateKey = (RSAPrivateKey) keyStore.getKey("pvktmp:bd5ba0e0-9718-48ea-b6e6-32cd9c852d76", "!c3c0ld".toCharArray());

//we have the private key
System.out.println("Private Key created");
System.out.println("Private Key Algorithm: " + privateKey.getAlgorithm());

//create the credential
BasicX509Credential decryptionCredential = new BasicX509Credential();
decryptionCredential.setPrivateKey(privateKey);

StaticKeyInfoCredentialResolver skicr = new StaticKeyInfoCredentialResolver(decryptionCredential);

//create a decrypter
Decrypter decrypter = new Decrypter(null, skicr, new InlineEncryptedKeyResolver());

//decrypt the first (and only) assertion
Assertion decryptedAssertion;

try
{
decryptedAssertion = decrypter.decrypt(response.getEncryptedAssertions().get(0));
}
catch (DecryptionException de)
{
System.out.println("Assertion decryption failed.");
System.out.println(de.getMessage());
return;
}

System.out.println("Assertion decryption succeeded.");
System.out.println("Assertion ID: " + decryptedAssertion.getID());

//loop through the nodes to get what we want
List<AttributeStatement> attributeStatements = decryptedAssertion.getAttributeStatements();
for (int i = 0; i < attributeStatements.size(); i++)
{
List<Attribute> attributes = attributeStatements.get(i).getAttributes();
for (int x = 0; x < attributes.size(); x++)
{
String strAttributeName = attributes.get(x).getDOM().getAttribute("Name");

List<XMLObject> attributeValues = attributes.get(x).getAttributeValues();
for (int y = 0; y < attributeValues.size(); y++)
{
String strAttributeValue = attributeValues.get(y).getDOM().getTextContent();
System.out.println(strAttributeName + ": " + strAttributeValue);
}
}
}
}
catch (Exception ex)
{
ex.printStackTrace();
}
}
}

13 comments:

Suresh Choudhary said...

hey hi,
Thanx for the code !
I'm a beginner and so i need more instructions as to how to configure the Platform (Eclipse) and OpenSaml (if ther r any)...
also plz tell me the steps to do it and how to run it as i am having my own webservice also!
Thanx in advance for that..

Anonymous said...

Dude. You rock. Thanks for this!

quailbot said...

Thank you. This is very useful! I was searching all over OpenSAML website for processing SAML2 response and wasn't able to find anything.

kevnls said...

I'm glad people are finding this useful. I'm going to post some code I have that illustrates processing a Response a little more completely very soon. It will be a little more copy/paste. Stay tuned.

Anne DiSciullo said...

Thank you for a very helpful post. It is very hard to find examples of processing a SAML2 response - especially getting the value from an attributeValue.

Anonymous said...

Thanks for extremely helpful code. One comment about verifying signatures. Often you will find that the assertions are signed instead of the response. In that case response.getSignature() will return null and you have to get the signature by calling assertion.getSignature()

Anonymous said...

Very helpful code...

Anonymous said...

Did you ever publish any further docs on parsing the response? I'm having problems casting my XMLObject from an AttributeValue to a class.

kevnls said...

Here is a new post that shows a more end-to-end example: http://kevnls.blogspot.com/2011/09/receiving-and-processing-saml-20.html

Accordian said...

This is very useful! I have one suggestion to make it even better for beginner - provide downloads for the xml's and certificates. I am anxious to try your example, but not sure where to get the inputs!

Would greatly appreciate it if you could post them - or explain how to create them. Thanks you so much!

kevnls said...

I actually have another post that can help you create certificates:

http://kevnls.blogspot.com/2009/05/creating-free-publicprivate-key-pair-in.html

Anonymous said...

Thanks so much for this code, my project would have been much harder without it! I did initially have problems getting the signature to validate -- it turned out to be a whitespace issue. Changing


parserPoolManager.setIgnoreElementContentWhitespace(true);

to

parserPoolManager.setIgnoreElementContentWhitespace(false);

fixed that problem -- hopefully this will help anyone else with the same issue.

Gobliins said...

This was bomba