[KEYCLOAK-18419] Support SAML 2.0 Encrypted IDs in Assertion

saml-core/src/main/java/org/keycloak/saml/processing/core/saml/v2/util/AssertionUtil.java

@@ -27,24 +27,30 @@ import org.keycloak.dom.saml.v2.assertion.AttributeStatementType.ASTChoiceType;
 import org.keycloak.dom.saml.v2.assertion.AttributeType;
 import org.keycloak.dom.saml.v2.assertion.ConditionsType;
 import org.keycloak.dom.saml.v2.assertion.EncryptedAssertionType;
+import org.keycloak.dom.saml.v2.assertion.EncryptedElementType;
 import org.keycloak.dom.saml.v2.assertion.NameIDType;
 import org.keycloak.dom.saml.v2.assertion.StatementAbstractType;
 import org.keycloak.dom.saml.v2.assertion.SubjectType;
 import org.keycloak.dom.saml.v2.assertion.SubjectType.STSubType;
 import org.keycloak.dom.saml.v2.protocol.ResponseType;
+import org.keycloak.rotation.HardcodedKeyLocator;
 import org.keycloak.rotation.KeyLocator;
 import org.keycloak.saml.common.ErrorCodes;
 import org.keycloak.saml.common.PicketLinkLogger;
 import org.keycloak.saml.common.PicketLinkLoggerFactory;
+import org.keycloak.saml.common.constants.GeneralConstants;
 import org.keycloak.saml.common.constants.JBossSAMLConstants;
 import org.keycloak.saml.common.exceptions.ConfigurationException;
 import org.keycloak.saml.common.exceptions.ParsingException;
 import org.keycloak.saml.common.exceptions.ProcessingException;
 import org.keycloak.saml.common.exceptions.fed.IssueInstantMissingException;
 import org.keycloak.saml.common.util.DocumentUtil;
+import org.keycloak.saml.common.util.StaxParserUtil;
 import org.keycloak.saml.common.util.StaxUtil;
 import org.keycloak.saml.processing.api.saml.v2.sig.SAML2Signature;
 import org.keycloak.saml.processing.core.parsers.saml.SAMLParser;
+import org.keycloak.saml.processing.core.parsers.util.SAMLParserUtil;
+import org.keycloak.saml.processing.core.saml.v2.common.SAMLDocumentHolder;
 import org.keycloak.saml.processing.core.saml.v2.writers.SAMLAssertionWriter;
 import org.keycloak.saml.processing.core.util.JAXPValidationUtil;
 import org.keycloak.saml.processing.core.util.XMLEncryptionUtil;
@@ -56,6 +62,8 @@ import org.w3c.dom.Node;
 import javax.xml.crypto.dsig.XMLSignature;
 import javax.xml.datatype.XMLGregorianCalendar;
 import javax.xml.namespace.QName;
+import javax.xml.stream.XMLEventReader;
+
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.security.PrivateKey;
@@ -64,10 +72,6 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 
-import org.keycloak.rotation.HardcodedKeyLocator;
-import org.keycloak.saml.common.constants.GeneralConstants;
-import org.keycloak.saml.processing.core.saml.v2.common.SAMLDocumentHolder;
-
 /**
  * Utility to deal with assertions
  *
@@ -608,4 +612,44 @@ public class AssertionUtil {
 
         return decryptedDocumentElement;
     }
+
+    public static boolean isIdEncrypted(final ResponseType responseType) {
+        final STSubType subTypeElement = getSubTypeElement(responseType);
+        return subTypeElement != null && subTypeElement.getEncryptedID() != null;
+    }
+
+    public static void decryptId(final ResponseType responseType, final PrivateKey privateKey) throws ConfigurationException, ProcessingException, ParsingException {
+        final STSubType subTypeElement = getSubTypeElement(responseType);
+        if(subTypeElement == null) {
+            return;
+        }
+        final EncryptedElementType encryptedID = subTypeElement.getEncryptedID();
+        if (encryptedID == null) {
+            return;
+        }
+        Element encryptedElement = encryptedID.getEncryptedElement();
+        Document newDoc = DocumentUtil.createDocument();
+        Node importedNode = newDoc.importNode(encryptedElement, true);
+        newDoc.appendChild(importedNode);
+        Element decryptedNameIdElement = XMLEncryptionUtil.decryptElementInDocument(newDoc, privateKey);
+
+        final XMLEventReader xmlEventReader = StaxParserUtil.getXMLEventReader(DocumentUtil.getNodeAsStream(decryptedNameIdElement));
+        NameIDType nameIDType = SAMLParserUtil.parseNameIDType(xmlEventReader);
+
+        // Add unencrypted id, remove encrypted
+        subTypeElement.addBaseID(nameIDType);
+        subTypeElement.setEncryptedID(null);
+    }
+
+    private static STSubType getSubTypeElement(final ResponseType responseType) {
+        final List<ResponseType.RTChoiceType> assertions = responseType.getAssertions();
+        if (assertions.isEmpty()) {
+            return null;
+        }
+        final AssertionType assertion = assertions.get(0).getAssertion();
+        if (assertion.getSubject() == null) {
+            return null;
+        }
+        return assertion.getSubject().getSubType();
+    }
 }

saml-core/src/test/java/org/keycloak/saml/processing/core/parsers/saml/SAMLParserTest.java

@@ -98,13 +98,12 @@ import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hamcrest.Matchers.nullValue;
-
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.assertFalse;
 /**
  * Test class for SAML parser.
  *
@@ -187,6 +186,18 @@ public class SAMLParserTest {
         assertThat(ea.getEncryptedElement().getLocalName(), is("EncryptedAssertion"));
     }
 
+    @Test
+    public void testSaml20EncryptedId() throws Exception {
+        ResponseType rt = assertParsed("saml20-encrypted-id-response.xml",  ResponseType.class);
+
+        assertThat(rt, notNullValue());
+        assertThat(rt.getAssertions(), notNullValue());
+        assertThat(rt.getAssertions().size(), is(1));
+        assertThat(rt.getAssertions().get(0).getAssertion().getSubject(), notNullValue());
+        assertThat(rt.getAssertions().get(0).getAssertion().getSubject().getSubType(), notNullValue());
+        assertThat(rt.getAssertions().get(0).getAssertion().getSubject().getSubType().getEncryptedID(), notNullValue());
+    }
+
     @Test
     public void testSaml20EncryptedAssertionWithNewlines() throws Exception {
         SAMLDocumentHolder holder = assertParsed("KEYCLOAK-4489-encrypted-assertion-with-newlines.xml", SAMLDocumentHolder.class);

saml-core/src/test/java/org/keycloak/saml/processing/core/saml/v2/util/AssertionUtilTest.java

@@ -1,16 +1,33 @@
 package org.keycloak.saml.processing.core.saml.v2.util;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayInputStream;
+import java.io.IOException;
 import java.io.InputStream;
+import java.io.StringReader;
+import java.security.KeyPair;
+import java.security.PrivateKey;
 import java.security.cert.X509Certificate;
+import java.util.Scanner;
 
+import org.bouncycastle.openssl.PEMKeyPair;
+import org.bouncycastle.openssl.PEMParser;
+import org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter;
 import org.bouncycastle.util.Arrays;
 import org.junit.Test;
 import org.keycloak.common.util.Base64;
 import org.keycloak.common.util.DerUtils;
+import org.keycloak.dom.saml.v2.assertion.NameIDType;
+import org.keycloak.dom.saml.v2.assertion.SubjectType.STSubType;
+import org.keycloak.dom.saml.v2.protocol.ResponseType;
+import org.keycloak.saml.processing.core.parsers.saml.SAMLParser;
+import org.keycloak.saml.processing.core.parsers.saml.SAMLParserTest;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 
@@ -55,4 +72,54 @@ public class AssertionUtilTest {
         }
     }
 
+    @Test
+    public void testSaml20DecryptId() throws Exception {
+        try (InputStream st = getEncryptedIdTestFileInputStream()) {
+            ResponseType responseType = (ResponseType) SAMLParser.getInstance().parse(st);
+
+            STSubType subType = responseType.getAssertions().get(0).getAssertion().getSubject().getSubType();
+
+            assertNotNull(subType.getEncryptedID());
+            assertNull(subType.getBaseID());
+
+            AssertionUtil.decryptId(responseType, extractPrivateKey());
+
+            assertNull(subType.getEncryptedID());
+            assertNotNull(subType.getBaseID());
+            assertTrue(subType.getBaseID() instanceof NameIDType);
+            assertEquals("myTestId",
+                    ((NameIDType) subType.getBaseID()).getValue());
+        }
+
+    }
+
+    private InputStream getEncryptedIdTestFileInputStream() {
+        return SAMLParserTest.class.getResourceAsStream("saml20-encrypted-id-response.xml");
+    }
+
+    private PrivateKey extractPrivateKey() throws IOException {
+        StringBuilder sb = new StringBuilder();
+        try (Scanner sc = new Scanner(getEncryptedIdTestFileInputStream())) {
+            while (sc.hasNextLine()) {
+                if (sc.nextLine().contains("BEGIN RSA PRIVATE KEY")) {
+                    sb.append("-----BEGIN RSA PRIVATE KEY-----").append("\n");
+                    while (sc.hasNextLine()) {
+                        String line = sc.nextLine();
+                        if (line.contains("END RSA PRIVATE KEY")) {
+                            sb.append("-----END RSA PRIVATE KEY-----");
+                            break;
+                        }
+                        sb.append(line).append("\n");
+                    }
+                }
+            }
+        }
+        assertNotEquals("PEM certificate not found in test data", 0, sb.length());
+        PEMParser pp = new PEMParser(new StringReader(sb.toString()));
+        PEMKeyPair pemKeyPair = (PEMKeyPair) pp.readObject();
+        KeyPair kp = new JcaPEMKeyConverter().getKeyPair(pemKeyPair);
+        pp.close();
+        return kp.getPrivate();
+    }
+
 }

saml-core/src/test/resources/org/keycloak/saml/processing/core/parsers/saml/saml20-encrypted-id-response.xml

@@ -0,0 +1,98 @@
+<samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion" ID="_8e8dc5f69a98cc4c1ff3427e5ce34606fd672f91e6" Version="2.0" IssueInstant="2014-07-17T01:01:48Z" Destination="http://sp.example.com/demo1/index.php?acs" InResponseTo="ONELOGIN_4fee3b046395c4e751011e97f8900b5273d56685">
+    <saml:Issuer>http://idp.example.com/metadata.php</saml:Issuer>
+    <samlp:Status>
+        <samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Success"/>
+    </samlp:Status>
+    <saml:Assertion xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xs="http://www.w3.org/2001/XMLSchema" ID="_d71a3a8e9fcc45c9e9d248ef7049393fc8f04e5f75" Version="2.0" IssueInstant="2014-07-17T01:01:48Z">
+        <saml:Issuer>http://idp.example.com/metadata.php</saml:Issuer>
+        <saml:Subject>
+            <saml:SubjectConfirmation Method="urn:oasis:names:tc:SAML:2.0:cm:bearer">
+                <saml:SubjectConfirmationData NotOnOrAfter="2024-01-18T06:21:48Z" Recipient="http://sp.example.com/demo1/index.php?acs" InResponseTo="ONELOGIN_4fee3b046395c4e751011e97f8900b5273d56685"/>
+            </saml:SubjectConfirmation>
+<!-- PEM Certificate containing keys for this test
+-BEGIN RSA PRIVATE KEY-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-END RSA PRIVATE KEY-
+
+Unencrypted NameID was (mind the namespace declaration!)
+<saml:NameID xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
+             SPNameQualifier="http://sp.example.com/demo1/metadata.php"
+             Format="urn:oasis:names:tc:SAML:2.0:nameid-format:transient">myTestId</saml:NameID>
+-->
+            <saml:EncryptedID><xenc:EncryptedData xmlns:xenc="http://www.w3.org/2001/04/xmlenc#" xmlns:dsig="http://www.w3.org/2000/09/xmldsig#" Type="http://www.w3.org/2001/04/xmlenc#Element"><xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes128-cbc"/><dsig:KeyInfo xmlns:dsig="http://www.w3.org/2000/09/xmldsig#"><xenc:EncryptedKey><xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-oaep-mgf1p"/><xenc:CipherData><xenc:CipherValue>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</xenc:CipherValue></xenc:CipherData></xenc:EncryptedKey></dsig:KeyInfo>
+                <xenc:CipherData>
+                    <xenc:CipherValue>yqORcbX52pH6GNSnqB4niJVqx02itNmoY6/IGr909sv18Cx9pTLyrPqWWeqdBF2tomkKKp7ZE+rzGxzdV7dR1RWELE7Q/r/s2HQXJgA26pOCCfXnQ7drxcMMjpsUU46qVsekyTPlUp+Tmn4ubqP/aGBeIJCXmvgkMijYFhRmt640ianfpLYSW2wxwmfrgVQP7CenxTkKKnNT56N2LYBPFcMEoIb0tvR3tHKmW2uA10S8QagWaWY8b+WEWJ7IYW49zS8zp94JZElQGnzZ/d0ay+iNDTBWFNaJsDQaykbayds=</xenc:CipherValue>
+                </xenc:CipherData>
+            </xenc:EncryptedData></saml:EncryptedID></saml:Subject>
+        <saml:Conditions NotBefore="2014-07-17T01:01:18Z" NotOnOrAfter="2024-01-18T06:21:48Z">
+            <saml:AudienceRestriction>
+                <saml:Audience>http://sp.example.com/demo1/metadata.php</saml:Audience>
+            </saml:AudienceRestriction>
+        </saml:Conditions>
+        <saml:AuthnStatement AuthnInstant="2014-07-17T01:01:48Z" SessionNotOnOrAfter="2024-07-17T09:01:48Z" SessionIndex="_be9967abd904ddcae3c0eb4189adbe3f71e327cf93">
+            <saml:AuthnContext>
+                <saml:AuthnContextClassRef>urn:oasis:names:tc:SAML:2.0:ac:classes:Password</saml:AuthnContextClassRef>
+            </saml:AuthnContext>
+        </saml:AuthnStatement>
+        <saml:AttributeStatement>
+            <saml:Attribute Name="uid" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:basic">
+                <saml:AttributeValue xsi:type="xs:string">test</saml:AttributeValue>
+            </saml:Attribute>
+            <saml:Attribute Name="mail" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:basic">
+                <saml:AttributeValue xsi:type="xs:string">test@example.com</saml:AttributeValue>
+            </saml:Attribute>
+            <saml:Attribute Name="eduPersonAffiliation" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:basic">
+                <saml:AttributeValue xsi:type="xs:string">users</saml:AttributeValue>
+                <saml:AttributeValue xsi:type="xs:string">examplerole1</saml:AttributeValue>
+            </saml:Attribute>
+        </saml:AttributeStatement>
+    </saml:Assertion>
+</samlp:Response>

services/src/main/java/org/keycloak/broker/saml/SAMLEndpoint.java

@@ -466,6 +466,10 @@ public class SAMLEndpoint {
                     return ErrorPage.error(session, authSession, Response.Status.BAD_REQUEST, Messages.INVALID_REQUESTER);
                 }
 
+                if(AssertionUtil.isIdEncrypted(responseType)) {
+                    // This methods writes the parsed and decrypted id back on the responseType parameter:
+                    AssertionUtil.decryptId(responseType, keys.getPrivateKey());
+                }
                 AssertionType assertion = responseType.getAssertions().get(0).getAssertion();
                 NameIDType subjectNameID = getSubjectNameID(assertion);
                 String principal = getPrincipal(assertion);

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/broker/KcSamlEncryptedIdTest.java

@@ -0,0 +1,116 @@
+package org.keycloak.testsuite.broker;
+
+import org.hamcrest.Matchers;
+import org.junit.Test;
+import org.keycloak.common.util.PemUtils;
+import org.keycloak.dom.saml.v2.protocol.AuthnRequestType;
+import org.keycloak.saml.RandomSecret;
+import org.keycloak.saml.common.constants.JBossSAMLConstants;
+import org.keycloak.saml.common.constants.JBossSAMLURIConstants;
+import org.keycloak.saml.common.exceptions.ConfigurationException;
+import org.keycloak.saml.common.exceptions.ParsingException;
+import org.keycloak.saml.common.exceptions.ProcessingException;
+import org.keycloak.saml.common.util.DocumentUtil;
+import org.keycloak.saml.processing.api.saml.v2.request.SAML2Request;
+import org.keycloak.saml.processing.core.saml.v2.common.SAMLDocumentHolder;
+import org.keycloak.saml.processing.core.util.XMLEncryptionUtil;
+import org.keycloak.testsuite.admin.ApiUtil;
+import org.keycloak.testsuite.util.SamlClient;
+import org.keycloak.testsuite.util.SamlClientBuilder;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.Node;
+
+import javax.crypto.SecretKey;
+import javax.crypto.spec.SecretKeySpec;
+import javax.xml.namespace.QName;
+import java.util.concurrent.atomic.AtomicReference;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.not;
+import static org.keycloak.saml.common.constants.JBossSAMLURIConstants.ASSERTION_NSURI;
+import static org.keycloak.testsuite.saml.AbstractSamlTest.SAML_ASSERTION_CONSUMER_URL_SALES_POST;
+import static org.keycloak.testsuite.saml.AbstractSamlTest.SAML_CLIENT_ID_SALES_POST;
+import static org.keycloak.testsuite.util.Matchers.isSamlResponse;
+
+public class KcSamlEncryptedIdTest extends AbstractBrokerTest {
+    @Override
+    protected BrokerConfiguration getBrokerConfiguration() {
+        return KcSamlBrokerConfiguration.INSTANCE;
+    }
+
+    @Test
+    public void testEncryptedIdIsReadable() throws ConfigurationException, ParsingException, ProcessingException {
+        createRolesForRealm(bc.consumerRealmName());
+
+        AuthnRequestType loginRep = SamlClient.createLoginRequestDocument(SAML_CLIENT_ID_SALES_POST, SAML_ASSERTION_CONSUMER_URL_SALES_POST, null);
+
+        Document doc = SAML2Request.convert(loginRep);
+
+        final AtomicReference<String> username = new AtomicReference<>();
+        assertThat(adminClient.realm(bc.consumerRealmName()).users().search(username.get()), hasSize(0));
+
+        SAMLDocumentHolder samlResponse = new SamlClientBuilder()
+                .authnRequest(getConsumerSamlEndpoint(bc.consumerRealmName()), doc, SamlClient.Binding.POST).build()   // Request to consumer IdP
+                .login().idp(bc.getIDPAlias()).build()
+
+                .processSamlResponse(SamlClient.Binding.POST)    // AuthnRequest to producer IdP
+                .targetAttributeSamlRequest()
+                .build()
+
+                .login().user(bc.getUserLogin(), bc.getUserPassword()).build()
+
+                .processSamlResponse(SamlClient.Binding.POST)    // Response from producer IdP
+                .transformDocument(document -> { // Replace Subject -> NameID with EncryptedId
+                    Node assertionElement = document.getDocumentElement()
+                            .getElementsByTagNameNS(ASSERTION_NSURI.get(), JBossSAMLConstants.ASSERTION.get()).item(0);
+
+                    if (assertionElement == null) {
+                        throw new IllegalStateException("Unable to find assertion in saml response document");
+                    }
+
+                    String samlNSPrefix = assertionElement.getPrefix();
+
+                    try {
+                        QName encryptedIdElementQName = new QName(ASSERTION_NSURI.get(), JBossSAMLConstants.ENCRYPTED_ID.get(), samlNSPrefix);
+                        QName nameIdQName = new QName(ASSERTION_NSURI.get(),
+                                JBossSAMLConstants.NAMEID.get(), samlNSPrefix);
+
+                        // Add xmlns:saml attribute to NameId element,
+                        // this is necessary as it is decrypted as a separate doc and saml namespace is not know
+                        // unless added to NameId element
+                        Element nameIdElement = DocumentUtil.getElement(document, nameIdQName);
+                        if (nameIdElement == null) {
+                            throw new RuntimeException("Assertion doesn't contain NameId " + DocumentUtil.asString(document));
+                        }
+                        nameIdElement.setAttribute("xmlns:" + samlNSPrefix, ASSERTION_NSURI.get());
+                        username.set(nameIdElement.getTextContent());
+
+                        byte[] secret = RandomSecret.createRandomSecret(128 / 8);
+                        SecretKey secretKey = new SecretKeySpec(secret, "AES");
+
+                        // encrypt the Assertion element and replace it with a EncryptedAssertion element.
+                        XMLEncryptionUtil.encryptElement(nameIdQName, document, PemUtils.decodePublicKey(ApiUtil.findActiveSigningKey(adminClient.realm(bc.consumerRealmName())).getPublicKey()),
+                                secretKey, 128, encryptedIdElementQName, true);
+                    } catch (Exception e) {
+                        throw new ProcessingException("failed to encrypt", e);
+                    }
+
+                    assertThat(DocumentUtil.asString(document), not(containsString(username.get())));
+                    return document;
+                })
+                .build()
+
+                // first-broker flow
+                .updateProfile().firstName("a").lastName("b").email(bc.getUserEmail()).build()
+                .followOneRedirect()
+                .getSamlResponse(SamlClient.Binding.POST);       // Response from consumer IdP
+
+        assertThat(samlResponse, Matchers.notNullValue());
+        assertThat(samlResponse.getSamlObject(), isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
+
+        assertThat(adminClient.realm(bc.consumerRealmName()).users().search(username.get()), hasSize(1));
+    }
+}