KEYCLOAK-11416 Fix nil AttributeValue handling

adapters/saml/core/src/main/java/org/keycloak/adapters/saml/profile/AbstractSamlAuthenticationHandler.java

@@ -569,19 +569,20 @@ public abstract class AbstractSamlAuthenticationHandler implements SamlAuthentic
     }
 
     private String getAttributeValue(Object attrValue) {
-        String value = null;
+        if (attrValue == null) {
-        if (attrValue instanceof String) {
+            return "";
-            value = (String) attrValue;
+        } else if (attrValue instanceof String) {
+            return (String) attrValue;
         } else if (attrValue instanceof Node) {
             Node roleNode = (Node) attrValue;
-            value = roleNode.getFirstChild().getNodeValue();
+            return roleNode.getFirstChild().getNodeValue();
         } else if (attrValue instanceof NameIDType) {
             NameIDType nameIdType = (NameIDType) attrValue;
-            value = nameIdType.getValue();
+            return nameIdType.getValue();
         } else {
             log.warn("Unable to extract unknown SAML assertion attribute value type: " + attrValue.getClass().getName());
         }
-        return value;
+        return null;
     }
 
     protected boolean isRole(AttributeType attribute) {

saml-core/src/main/java/org/keycloak/saml/processing/core/saml/v2/writers/BaseWriter.java

@@ -174,6 +174,8 @@ public class BaseWriter {
                     	writeNameIDTypeAttributeValue((NameIDType) attributeValue);
                     } else
                         throw logger.writerUnsupportedAttributeValueError(attributeValue.getClass().getName());
+                } else {
+                    writeStringAttributeValue(null);
                 }
             }
         }
@@ -191,7 +193,13 @@ public class BaseWriter {
         StaxUtil.writeNameSpace(writer, JBossSAMLURIConstants.XSI_PREFIX.get(), JBossSAMLURIConstants.XSI_NSURI.get());
         StaxUtil.writeNameSpace(writer, "xs", JBossSAMLURIConstants.XMLSCHEMA_NSURI.get());
         StaxUtil.writeAttribute(writer, "xsi", JBossSAMLURIConstants.XSI_NSURI.get(), "type", "xs:string");
-        StaxUtil.writeCharacters(writer, attributeValue);
+
+        if (attributeValue == null) {
+            StaxUtil.writeAttribute(writer, "xsi", JBossSAMLURIConstants.XSI_NSURI.get(), "nil", "true");
+        } else {
+            StaxUtil.writeCharacters(writer, attributeValue);
+        }
+
         StaxUtil.writeEndElement(writer);
     }
 

services/src/main/java/org/keycloak/broker/saml/mappers/AttributeToRoleMapper.java

@@ -36,6 +36,7 @@ import org.keycloak.provider.ProviderConfigProperty;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 
 /**
  * @author <a href="mailto:bill@burkecentral.com">Bill Burke</a>
@@ -121,7 +122,7 @@ public class AttributeToRoleMapper extends AbstractIdentityProviderMapper {
         if (name != null && name.trim().equals("")) name = null;
         String friendly = mapperModel.getConfig().get(ATTRIBUTE_FRIENDLY_NAME);
         if (friendly != null && friendly.trim().equals("")) friendly = null;
-        String desiredValue = mapperModel.getConfig().get(ATTRIBUTE_VALUE);
+        String desiredValue = Optional.ofNullable(mapperModel.getConfig().get(ATTRIBUTE_VALUE)).orElse("");
         AssertionType assertion = (AssertionType)context.getContextData().get(SAMLEndpoint.SAML_ASSERTION);
         for (AttributeStatementType statement : assertion.getAttributeStatements()) {
             for (AttributeStatementType.ASTChoiceType choice : statement.getAttributes()) {
@@ -129,7 +130,9 @@ public class AttributeToRoleMapper extends AbstractIdentityProviderMapper {
                 if (name != null && !name.equals(attr.getName())) continue;
                 if (friendly != null && !friendly.equals(attr.getFriendlyName())) continue;
                 for (Object val : attr.getAttributeValue()) {
-                    if (val.equals(desiredValue)) return true;
+                    val = Optional.ofNullable(val).orElse("");
+                    if (val.equals(desiredValue))
+                        return true;
                 }
             }
         }

testsuite/integration-arquillian/test-apps/servlets/src/main/java/org/keycloak/testsuite/adapter/servlet/SendUsernameServlet.java

@@ -44,6 +44,7 @@ import java.security.Principal;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map.Entry;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.transform.OutputKeys;
 import javax.xml.transform.Transformer;
@@ -249,26 +250,42 @@ public class SendUsernameServlet {
         return output + "</body></html>";
     }
 
-    private String getAttributes() {
+    private static String joinList(String delimeter, List<String> list) {
-        SamlPrincipal principal = (SamlPrincipal) sentPrincipal;
+        if (list == null || list.size() <= 0) return "";
-        String output = "attribute email: " + principal.getAttribute(X500SAMLProfileConstants.EMAIL.get());
+
-        output += "<br /> topAttribute: " + principal.getAttribute("topAttribute");
+        StringBuilder sb = new StringBuilder();
-        output += "<br /> boolean-attribute: " + principal.getAttribute("boolean-attribute");
+
-        output += "<br /> level2Attribute: " + principal.getAttribute("level2Attribute");
+        for (int i = 0; i < list.size(); i++) {
-        output += "<br /> group: " + principal.getAttributes("group").toString();
+
-        output += "<br /> friendlyAttribute email: " + principal.getFriendlyAttribute("email");
+            sb.append(list.get(i));
-        output += "<br /> phone: " + principal.getAttribute("phone");
+
-        output += "<br /> friendlyAttribute phone: " + principal.getFriendlyAttribute("phone");
+            // if not the last item
-        output += "<br /> hardcoded-attribute: ";
+            if (i != list.size() - 1) {
-        for (String attr : principal.getAttributes("hardcoded-attribute")) {
+                sb.append(delimeter);
-            output += attr + ",";
+            }
-        }
+
-        output += "<br /> group-attribute: ";
-        for (String attr : principal.getAttributes("group-attribute")) {
-            output += attr + ",";
         }
 
-        return output;
+        return sb.toString();
+    }
+
+    private String getAttributes() {
+        SamlPrincipal principal = (SamlPrincipal) sentPrincipal;
+
+        StringBuilder b = new StringBuilder();
+        for (Entry<String, List<String>> e : principal.getAttributes().entrySet()) {
+            b.append(e.getKey()).append(": ").append(joinList(",", e.getValue())).append("<br />");
+        }
+
+        for (String friendlyAttributeName : principal.getFriendlyNames()) {
+            b.append("friendly ")
+                    .append(friendlyAttributeName)
+                    .append(": ")
+                    .append(joinList(",", principal.getFriendlyAttributes(friendlyAttributeName)))
+                    .append("<br />");
+        }
+
+        return b.toString();
     }
 
     @GET

testsuite/integration-arquillian/tests/base/src/main/java/org/keycloak/testsuite/util/TestCleanup.java

@@ -61,11 +61,12 @@ public class TestCleanup {
     }
 
 
-    public void addCleanup(Runnable r) {
+    public TestCleanup addCleanup(Runnable r) {
         genericCleanups.add(r);
+        return this;
     }
 
-    public void addCleanup(AutoCloseable c) {
+    public TestCleanup addCleanup(AutoCloseable c) {
         genericCleanups.add(() -> {
             try {
                 c.close();
@@ -73,6 +74,7 @@ public class TestCleanup {
                 // ignore
             }
         });
+        return this;
     }
 
     public void addUserId(String userId) {

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/AbstractSAMLServletAdapterTest.java

@@ -6,19 +6,30 @@ import org.apache.http.client.methods.HttpUriRequest;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.util.EntityUtils;
+import org.keycloak.admin.client.resource.ProtocolMappersResource;
+import org.keycloak.representations.idm.ProtocolMapperRepresentation;
 import org.keycloak.representations.idm.RealmRepresentation;
 import org.keycloak.testsuite.adapter.AbstractServletsAdapterTest;
 import org.keycloak.testsuite.adapter.filter.AdapterActionsFilter;
+import org.keycloak.testsuite.auth.page.login.Login;
+import org.keycloak.testsuite.page.AbstractPage;
+import org.keycloak.testsuite.util.SamlClient;
+import org.keycloak.testsuite.util.SamlClientBuilder;
 import org.keycloak.testsuite.utils.io.IOUtil;
 
+import javax.ws.rs.core.Response;
 import javax.ws.rs.core.UriBuilder;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static org.keycloak.testsuite.admin.ApiUtil.getCreatedId;
 import static org.keycloak.testsuite.auth.page.AuthRealm.SAMLSERVLETDEMO;
+import static org.keycloak.testsuite.util.URLAssert.assertCurrentUrlStartsWith;
+import static org.keycloak.testsuite.util.WaitUtils.waitForPageToLoad;
 
 public abstract class AbstractSAMLServletAdapterTest extends AbstractServletsAdapterTest {
 
@@ -59,4 +70,32 @@ public abstract class AbstractSAMLServletAdapterTest extends AbstractServletsAda
                     }
                 });
     }
+
+    protected SamlClientBuilder beginAuthenticationAndLogin(AbstractPage page, SamlClient.Binding binding) {
+        return new SamlClientBuilder()
+                .navigateTo(page.buildUri())
+                .processSamlResponse(binding) // Process AuthnResponse
+                .build()
+
+                .login().user(bburkeUser)
+                .build();
+    }
+
+    protected AutoCloseable createProtocolMapper(ProtocolMappersResource resource, String name, String protocol, String protocolMapper, Map<String, String> config) {
+        ProtocolMapperRepresentation representation = new ProtocolMapperRepresentation();
+        representation.setName(name);
+        representation.setProtocol(protocol);
+        representation.setProtocolMapper(protocolMapper);
+        representation.setConfig(config);
+        try (Response response = resource.createMapper(representation)) {
+            String createdId = getCreatedId(response);
+            return () -> resource.delete(createdId);
+        }
+    }
+
+    protected void checkLoggedOut(AbstractPage page, Login loginPage) {
+        page.navigateTo();
+        waitForPageToLoad();
+        assertCurrentUrlStartsWith(loginPage);
+    }
 }

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/SAMLFilterLoginResponseHandlingTest.java

@@ -0,0 +1,34 @@
+package org.keycloak.testsuite.adapter.servlet;
+
+import org.junit.Ignore;
+import org.junit.Test;
+import org.keycloak.testsuite.arquillian.annotation.AppServerContainer;
+import org.keycloak.testsuite.utils.annotation.UseServletFilter;
+import org.keycloak.testsuite.utils.arquillian.ContainerConstants;
+
+/**
+ * @author mhajas
+ */
+@AppServerContainer(ContainerConstants.APP_SERVER_UNDERTOW)
+@AppServerContainer(ContainerConstants.APP_SERVER_WILDFLY)
+@AppServerContainer(ContainerConstants.APP_SERVER_WILDFLY_DEPRECATED)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP6)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP71)
+@UseServletFilter(filterName = "saml-filter", filterClass = "org.keycloak.adapters.saml.servlet.SamlFilter",
+        filterDependency = "org.keycloak:keycloak-saml-servlet-filter-adapter")
+public class SAMLFilterLoginResponseHandlingTest extends SAMLLoginResponseHandlingTest {
+    @Test
+    @Override
+    @Ignore
+    public void testErrorHandlingUnsigned() {
+
+    }
+
+    @Test
+    @Override
+    @Ignore
+    public void testErrorHandlingSigned() {
+
+    }
+}

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/SAMLFilterServletAdapterTest.java

@@ -92,20 +92,6 @@ public class SAMLFilterServletAdapterTest extends SAMLServletAdapterTest {
 
     }
 
-    @Test
-    @Override
-    @Ignore
-    public void testErrorHandlingUnsigned() {
-
-    }
-
-    @Test
-    @Override
-    @Ignore
-    public void testErrorHandlingSigned() {
-
-    }
-
     @Test
     @Override
     @Ignore

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/SAMLLoginResponseHandlingTest.java

@@ -0,0 +1,266 @@
+package org.keycloak.testsuite.adapter.servlet;
+
+import org.jboss.arquillian.container.test.api.Deployment;
+import org.jboss.arquillian.graphene.page.Page;
+import org.jboss.shrinkwrap.api.spec.WebArchive;
+import org.junit.Assert;
+import org.junit.Test;
+import org.keycloak.adapters.rotation.PublicKeyLocator;
+import org.keycloak.admin.client.resource.ClientResource;
+import org.keycloak.admin.client.resource.ProtocolMappersResource;
+import org.keycloak.dom.saml.v2.assertion.AttributeStatementType;
+import org.keycloak.dom.saml.v2.assertion.AttributeType;
+import org.keycloak.dom.saml.v2.assertion.StatementAbstractType;
+import org.keycloak.dom.saml.v2.protocol.ResponseType;
+import org.keycloak.protocol.saml.mappers.AttributeStatementHelper;
+import org.keycloak.protocol.saml.mappers.RoleListMapper;
+import org.keycloak.representations.idm.ProtocolMapperRepresentation;
+import org.keycloak.saml.SAML2ErrorResponseBuilder;
+import org.keycloak.saml.common.constants.JBossSAMLURIConstants;
+import org.keycloak.saml.processing.core.saml.v2.constants.X500SAMLProfileConstants;
+import org.keycloak.testsuite.adapter.filter.AdapterActionsFilter;
+import org.keycloak.testsuite.adapter.page.Employee2Servlet;
+import org.keycloak.testsuite.adapter.page.EmployeeSigServlet;
+import org.keycloak.testsuite.admin.ApiUtil;
+import org.keycloak.testsuite.arquillian.annotation.AppServerContainer;
+import org.keycloak.testsuite.saml.AbstractSamlTest;
+import org.keycloak.testsuite.util.Matchers;
+import org.keycloak.testsuite.util.SamlClient;
+import org.keycloak.testsuite.util.SamlClientBuilder;
+import org.keycloak.testsuite.util.WaitUtils;
+import org.keycloak.testsuite.utils.arquillian.ContainerConstants;
+import org.openqa.selenium.By;
+import org.w3c.dom.Document;
+
+import javax.ws.rs.core.Response;
+import java.net.URI;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.junit.Assert.assertThat;
+import static org.keycloak.testsuite.admin.ApiUtil.getCreatedId;
+import static org.keycloak.testsuite.saml.AbstractSamlTest.REALM_PRIVATE_KEY;
+import static org.keycloak.testsuite.saml.AbstractSamlTest.REALM_PUBLIC_KEY;
+import static org.keycloak.testsuite.util.Matchers.bodyHC;
+import static org.keycloak.testsuite.util.Matchers.statusCodeIsHC;
+import static org.keycloak.testsuite.util.URLAssert.assertCurrentUrlStartsWith;
+import static org.keycloak.testsuite.util.WaitUtils.waitForPageToLoad;
+import static org.keycloak.testsuite.util.WaitUtils.waitUntilElement;
+
+/**
+ * @author mhajas
+ */
+@AppServerContainer(ContainerConstants.APP_SERVER_UNDERTOW)
+@AppServerContainer(ContainerConstants.APP_SERVER_WILDFLY)
+@AppServerContainer(ContainerConstants.APP_SERVER_WILDFLY_DEPRECATED)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP6)
+@AppServerContainer(ContainerConstants.APP_SERVER_EAP71)
+@AppServerContainer(ContainerConstants.APP_SERVER_TOMCAT7)
+@AppServerContainer(ContainerConstants.APP_SERVER_TOMCAT8)
+@AppServerContainer(ContainerConstants.APP_SERVER_TOMCAT9)
+@AppServerContainer(ContainerConstants.APP_SERVER_JETTY92)
+@AppServerContainer(ContainerConstants.APP_SERVER_JETTY93)
+@AppServerContainer(ContainerConstants.APP_SERVER_JETTY94)
+public class SAMLLoginResponseHandlingTest extends AbstractSAMLServletAdapterTest {
+
+    @Page
+    protected Employee2Servlet employee2ServletPage;
+
+    @Page
+    protected EmployeeSigServlet employeeSigServletPage;
+
+    @Deployment(name = Employee2Servlet.DEPLOYMENT_NAME)
+    protected static WebArchive employee2() {
+        return samlServletDeployment(Employee2Servlet.DEPLOYMENT_NAME, WEB_XML_WITH_ACTION_FILTER, SendUsernameServlet.class, AdapterActionsFilter.class, PublicKeyLocator.class);
+    }
+
+    @Deployment(name = EmployeeSigServlet.DEPLOYMENT_NAME)
+    protected static WebArchive employeeSig() {
+        return samlServletDeployment(EmployeeSigServlet.DEPLOYMENT_NAME, SendUsernameServlet.class);
+    }
+
+    @Test
+    public void testNilAttributeValueAttribute() {
+        beginAuthenticationAndLogin(employee2ServletPage, SamlClient.Binding.POST)
+                .processSamlResponse(SamlClient.Binding.POST) // Update response with Nil attribute
+                .transformObject(ob -> {
+                    assertThat(ob, Matchers.isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
+                    ResponseType resp = (ResponseType) ob;
+
+                    Set<StatementAbstractType> statements = resp.getAssertions().get(0).getAssertion().getStatements();
+
+                    AttributeStatementType attributeType = (AttributeStatementType) statements.stream()
+                            .filter(statement -> statement instanceof AttributeStatementType)
+                            .findFirst().orElse(new AttributeStatementType());
+
+                    AttributeType attr = new AttributeType("attribute-with-null-attribute-value");
+                    attr.addAttributeValue(null);
+
+                    attributeType.addAttribute(new AttributeStatementType.ASTChoiceType(attr));
+                    resp.getAssertions().get(0).getAssertion().addStatement(attributeType);
+
+                    return ob;
+                })
+                .build()
+                .navigateTo(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build())
+                .execute(response -> {
+                            Assert.assertThat(response, statusCodeIsHC(Response.Status.OK));
+                            Assert.assertThat(response, bodyHC(containsString("attribute-with-null-attribute-value: <br />")));
+                        }
+                );
+    }
+
+    @Test
+    public void testErrorHandlingUnsigned() throws Exception {
+        SAML2ErrorResponseBuilder builder = new SAML2ErrorResponseBuilder()
+                .destination(employeeSigServletPage.toString() + "/saml")
+                .issuer("http://localhost:" + System.getProperty("auth.server.http.port", "8180") + "/realms/demo")
+                .status(JBossSAMLURIConstants.STATUS_REQUEST_DENIED.get());
+        Document document = builder.buildDocument();
+
+        new SamlClientBuilder()
+                .addStep((client, currentURI, currentResponse, context) ->
+                        SamlClient.Binding.REDIRECT.createSamlUnsignedResponse(URI.create(employeeSigServletPage.toString() + "/saml"), null, document))
+                .execute(closeableHttpResponse -> Assert.assertThat(closeableHttpResponse, bodyHC(containsString("INVALID_SIGNATURE"))));
+    }
+
+    @Test
+    public void testErrorHandlingSigned() throws Exception {
+        SAML2ErrorResponseBuilder builder = new SAML2ErrorResponseBuilder()
+                .destination(employeeSigServletPage.toString() + "/saml")
+                .issuer("http://localhost:" + System.getProperty("auth.server.http.port", "8180") + "/realms/demo")
+                .status(JBossSAMLURIConstants.STATUS_REQUEST_DENIED.get());
+        Document document = builder.buildDocument();
+
+        new SamlClientBuilder()
+                .addStep((client, currentURI, currentResponse, context) ->
+                        SamlClient.Binding.REDIRECT.createSamlSignedResponse(URI.create(employeeSigServletPage.toString() + "/saml"), null, document, REALM_PRIVATE_KEY, REALM_PUBLIC_KEY))
+                .execute(closeableHttpResponse -> Assert.assertThat(closeableHttpResponse, bodyHC(containsString("ERROR_STATUS"))));
+    }
+
+    @Test
+    public void testAttributes() throws Exception {
+        ClientResource clientResource = ApiUtil.findClientResourceByClientId(testRealmResource(), AbstractSamlTest.SAML_CLIENT_ID_EMPLOYEE_2);
+        ProtocolMappersResource protocolMappersResource = clientResource.getProtocolMappers();
+
+        Map<String, String> config = new LinkedHashMap<>();
+        config.put("attribute.nameformat", "Basic");
+        config.put("user.attribute", "topAttribute");
+        config.put("attribute.name", "topAttribute");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "topAttribute", "saml", "saml-user-attribute-mapper", config));
+
+        config = new LinkedHashMap<>();
+        config.put("attribute.nameformat", "Basic");
+        config.put("user.attribute", "level2Attribute");
+        config.put("attribute.name", "level2Attribute");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "level2Attribute", "saml", "saml-user-attribute-mapper", config));
+
+        config = new LinkedHashMap<>();
+        config.put("attribute.nameformat", "Basic");
+        config.put("single", "true");
+        config.put("attribute.name", "group");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "groups", "saml", "saml-group-membership-mapper", config));
+
+        setRolesToCheck("manager,user");
+
+        employee2ServletPage.navigateTo();
+        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
+        testRealmSAMLPostLoginPage.form().login("level2GroupUser", "password");
+
+        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
+        waitUntilElement(By.xpath("//body")).text().contains("topAttribute: true");
+        waitUntilElement(By.xpath("//body")).text().contains("level2Attribute: true");
+        waitUntilElement(By.xpath("//body")).text().contains(X500SAMLProfileConstants.EMAIL.get() + ": level2@redhat.com");
+        waitUntilElement(By.xpath("//body")).text().not().contains("group: []");
+        waitUntilElement(By.xpath("//body")).text().not().contains("group: null");
+        waitUntilElement(By.xpath("//body")).text().not().contains("group: <br />");
+        waitUntilElement(By.xpath("//body")).text().contains("group: level2");
+
+        employee2ServletPage.logout();
+        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
+
+        setRolesToCheck("manager,employee,user");
+
+        employee2ServletPage.navigateTo();
+        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
+        testRealmSAMLPostLoginPage.form().login(bburkeUser);
+
+        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
+        waitUntilElement(By.xpath("//body")).text().contains(X500SAMLProfileConstants.EMAIL.get() + ": bburke@redhat.com");
+        waitUntilElement(By.xpath("//body")).text().contains("friendly email: bburke@redhat.com");
+        waitUntilElement(By.xpath("//body")).text().contains("phone: 617");
+        waitUntilElement(By.xpath("//body")).text().not().contains("friendly phone:");
+
+        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAssertionFromDocument").build().toURL());
+        waitForPageToLoad();
+        Assert.assertEquals("", driver.getPageSource());
+
+        employee2ServletPage.logout();
+        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
+
+        config = new LinkedHashMap<>();
+        config.put("attribute.value", "hard");
+        config.put("attribute.nameformat", "Basic");
+        config.put("attribute.name", "hardcoded-attribute");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "hardcoded-attribute", "saml", "saml-hardcode-attribute-mapper", config));
+
+        config = new LinkedHashMap<>();
+        config.put("role", "hardcoded-role");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "hardcoded-role", "saml", "saml-hardcode-role-mapper", config));
+
+        config = new LinkedHashMap<>();
+        config.put("new.role.name", "pee-on");
+        config.put("role", "http://localhost:8280/employee/.employee");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "renamed-employee-role", "saml", "saml-role-name-mapper", config));
+
+        for (ProtocolMapperRepresentation mapper : clientResource.toRepresentation().getProtocolMappers()) {
+            if (mapper.getName().equals("role-list")) {
+                protocolMappersResource.delete(mapper.getId());
+                Map<String, String> origConfig = new HashMap<>(mapper.getConfig());
+
+                mapper.setId(null);
+                mapper.getConfig().put(RoleListMapper.SINGLE_ROLE_ATTRIBUTE, "true");
+                mapper.getConfig().put(AttributeStatementHelper.SAML_ATTRIBUTE_NAME, "memberOf");
+
+                try (Response response = protocolMappersResource.createMapper(mapper)) {
+                    String createdId = getCreatedId(response);
+                    getCleanup().addCleanup((Runnable) () -> {
+                        protocolMappersResource.delete(createdId);
+                        mapper.setConfig(origConfig);
+                        protocolMappersResource.createMapper(mapper).close();
+                    });
+                }
+            }
+        }
+
+        setRolesToCheck("pee-on,el-jefe,manager,hardcoded-role");
+
+        config = new LinkedHashMap<>();
+        config.put("new.role.name", "el-jefe");
+        config.put("role", "user");
+        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "renamed-role", "saml", "saml-role-name-mapper", config));
+
+        employee2ServletPage.navigateTo();
+        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
+        testRealmSAMLPostLoginPage.form().login(bburkeUser);
+
+        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
+        waitUntilElement(By.xpath("//body")).text().contains("hardcoded-attribute: hard");
+        employee2ServletPage.checkRolesEndPoint(false);
+        employee2ServletPage.logout();
+        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
+    }
+
+    private void setRolesToCheck(String roles) throws Exception {
+        employee2ServletPage.navigateTo();
+        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
+        testRealmSAMLPostLoginPage.form().login(bburkeUser);
+        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("setCheckRoles").queryParam("roles", roles).build().toURL());
+        WaitUtils.waitUntilElement(By.tagName("body")).text().contains("These roles will be checked:");
+        employee2ServletPage.logout();
+    }
+}

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/SAMLServletAdapterTest.java

@@ -515,12 +515,6 @@ public class SAMLServletAdapterTest extends AbstractSAMLServletAdapterTest {
         checkLoggedOut(page, loginPage);
     }
 
-    private void checkLoggedOut(AbstractPage page, Login loginPage) {
-        page.navigateTo();
-        waitForPageToLoad();
-        assertCurrentUrlStartsWith(loginPage);
-    }
-
     @Test
     public void disabledClientTest() {
         ClientResource clientResource = ApiUtil.findClientResourceByClientId(testRealmResource(), AbstractSamlTest.SAML_CLIENT_ID_SALES_POST_SIG);
@@ -1152,34 +1146,6 @@ public class SAMLServletAdapterTest extends AbstractSAMLServletAdapterTest {
         Assert.assertEquals(driver.getCurrentUrl(), missingAssertionSigPage.getUriBuilder().clone().path("saml").build().toASCIIString());
     }
 
-    @Test
-    public void testErrorHandlingUnsigned() throws Exception {
-        SAML2ErrorResponseBuilder builder = new SAML2ErrorResponseBuilder()
-                .destination(employeeSigServletPage.toString() + "/saml")
-                .issuer("http://localhost:" + System.getProperty("auth.server.http.port", "8180") + "/realms/demo")
-                .status(JBossSAMLURIConstants.STATUS_REQUEST_DENIED.get());
-        Document document = builder.buildDocument();
-
-        new SamlClientBuilder()
-                .addStep((client, currentURI, currentResponse, context) ->
-                        Binding.REDIRECT.createSamlUnsignedResponse(URI.create(employeeSigServletPage.toString() + "/saml"), null, document))
-                .execute(closeableHttpResponse -> Assert.assertThat(closeableHttpResponse, bodyHC(containsString("INVALID_SIGNATURE"))));
-    }
-
-    @Test
-    public void testErrorHandlingSigned() throws Exception {
-        SAML2ErrorResponseBuilder builder = new SAML2ErrorResponseBuilder()
-                .destination(employeeSigServletPage.toString() + "/saml")
-                .issuer("http://localhost:" + System.getProperty("auth.server.http.port", "8180") + "/realms/demo")
-                .status(JBossSAMLURIConstants.STATUS_REQUEST_DENIED.get());
-        Document document = builder.buildDocument();
-
-        new SamlClientBuilder()
-                .addStep((client, currentURI, currentResponse, context) ->
-                        Binding.REDIRECT.createSamlSignedResponse(URI.create(employeeSigServletPage.toString() + "/saml"), null, document, REALM_PRIVATE_KEY, REALM_PUBLIC_KEY))
-                .execute(closeableHttpResponse -> Assert.assertThat(closeableHttpResponse, bodyHC(containsString("ERROR_STATUS"))));
-    }
-
     @Test
     public void testRelayStateEncoding() throws Exception {
         // this test has a hardcoded SAMLRequest and we hack a SP face servlet to get the SAMLResponse so we can look
@@ -1381,118 +1347,6 @@ public class SAMLServletAdapterTest extends AbstractSAMLServletAdapterTest {
         }
     }
 
-    @Test
-    public void testAttributes() throws Exception {
-        ClientResource clientResource = ApiUtil.findClientResourceByClientId(testRealmResource(), AbstractSamlTest.SAML_CLIENT_ID_EMPLOYEE_2);
-        ProtocolMappersResource protocolMappersResource = clientResource.getProtocolMappers();
-
-        Map<String, String> config = new LinkedHashMap<>();
-        config.put("attribute.nameformat", "Basic");
-        config.put("user.attribute", "topAttribute");
-        config.put("attribute.name", "topAttribute");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "topAttribute", "saml", "saml-user-attribute-mapper", config));
-
-        config = new LinkedHashMap<>();
-        config.put("attribute.nameformat", "Basic");
-        config.put("user.attribute", "level2Attribute");
-        config.put("attribute.name", "level2Attribute");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "level2Attribute", "saml", "saml-user-attribute-mapper", config));
-
-        config = new LinkedHashMap<>();
-        config.put("attribute.nameformat", "Basic");
-        config.put("single", "true");
-        config.put("attribute.name", "group");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "groups", "saml", "saml-group-membership-mapper", config));
-
-        setRolesToCheck("manager,user");
-
-        employee2ServletPage.navigateTo();
-        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
-        testRealmSAMLPostLoginPage.form().login("level2GroupUser", "password");
-
-        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
-        waitUntilElement(By.xpath("//body")).text().contains("topAttribute: true");
-        waitUntilElement(By.xpath("//body")).text().contains("level2Attribute: true");
-        waitUntilElement(By.xpath("//body")).text().contains("attribute email: level2@redhat.com");
-        waitUntilElement(By.xpath("//body")).text().not().contains("group: []");
-        waitUntilElement(By.xpath("//body")).text().not().contains("group: null");
-        waitUntilElement(By.xpath("//body")).text().contains("group: [level2]");
-
-        employee2ServletPage.logout();
-        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
-
-        setRolesToCheck("manager,employee,user");
-
-        employee2ServletPage.navigateTo();
-        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
-        testRealmSAMLPostLoginPage.form().login(bburkeUser);
-
-        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
-        waitUntilElement(By.xpath("//body")).text().contains("attribute email: bburke@redhat.com");
-        waitUntilElement(By.xpath("//body")).text().contains("friendlyAttribute email: bburke@redhat.com");
-        waitUntilElement(By.xpath("//body")).text().contains("phone: 617");
-        waitUntilElement(By.xpath("//body")).text().contains("friendlyAttribute phone: null");
-
-        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAssertionFromDocument").build().toURL());
-        waitForPageToLoad();
-        Assert.assertEquals("", driver.getPageSource());
-
-        employee2ServletPage.logout();
-        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
-
-        config = new LinkedHashMap<>();
-        config.put("attribute.value", "hard");
-        config.put("attribute.nameformat", "Basic");
-        config.put("attribute.name", "hardcoded-attribute");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "hardcoded-attribute", "saml", "saml-hardcode-attribute-mapper", config));
-
-        config = new LinkedHashMap<>();
-        config.put("role", "hardcoded-role");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "hardcoded-role", "saml", "saml-hardcode-role-mapper", config));
-
-        config = new LinkedHashMap<>();
-        config.put("new.role.name", "pee-on");
-        config.put("role", "http://localhost:8280/employee/.employee");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "renamed-employee-role", "saml", "saml-role-name-mapper", config));
-
-        for (ProtocolMapperRepresentation mapper : clientResource.toRepresentation().getProtocolMappers()) {
-            if (mapper.getName().equals("role-list")) {
-                protocolMappersResource.delete(mapper.getId());
-                Map<String, String> origConfig = new HashMap<>(mapper.getConfig());
-
-                mapper.setId(null);
-                mapper.getConfig().put(RoleListMapper.SINGLE_ROLE_ATTRIBUTE, "true");
-                mapper.getConfig().put(AttributeStatementHelper.SAML_ATTRIBUTE_NAME, "memberOf");
-
-                try (Response response = protocolMappersResource.createMapper(mapper)) {
-                    String createdId = getCreatedId(response);
-                    getCleanup().addCleanup((Runnable) () -> {
-                        protocolMappersResource.delete(createdId);
-                        mapper.setConfig(origConfig);
-                        protocolMappersResource.createMapper(mapper).close();
-                    });
-                }
-            }
-        }
-
-        setRolesToCheck("pee-on,el-jefe,manager,hardcoded-role");
-
-        config = new LinkedHashMap<>();
-        config.put("new.role.name", "el-jefe");
-        config.put("role", "user");
-        getCleanup().addCleanup(createProtocolMapper(protocolMappersResource, "renamed-role", "saml", "saml-role-name-mapper", config));
-
-        employee2ServletPage.navigateTo();
-        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
-        testRealmSAMLPostLoginPage.form().login(bburkeUser);
-
-        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("getAttributes").build().toURL());
-        waitUntilElement(By.xpath("//body")).text().contains("hardcoded-attribute: hard");
-        employee2ServletPage.checkRolesEndPoint(false);
-        employee2ServletPage.logout();
-        checkLoggedOut(employee2ServletPage, testRealmSAMLPostLoginPage);
-    }
-
     @Test
     public void idpMetadataValidation() throws Exception {
         driver.navigate().to(authServerPage.toString() + "/realms/" + SAMLSERVLETDEMO + "/protocol/saml/descriptor");
@@ -1939,27 +1793,6 @@ public class SAMLServletAdapterTest extends AbstractSAMLServletAdapterTest {
         }
     }
 
-    private AutoCloseable createProtocolMapper(ProtocolMappersResource resource, String name, String protocol, String protocolMapper, Map<String, String> config) {
-        ProtocolMapperRepresentation representation = new ProtocolMapperRepresentation();
-        representation.setName(name);
-        representation.setProtocol(protocol);
-        representation.setProtocolMapper(protocolMapper);
-        representation.setConfig(config);
-        try (Response response = resource.createMapper(representation)) {
-            String createdId = getCreatedId(response);
-            return () -> resource.delete(createdId);
-        }
-    }
-
-    private void setRolesToCheck(String roles) throws Exception {
-        employee2ServletPage.navigateTo();
-        assertCurrentUrlStartsWith(testRealmSAMLPostLoginPage);
-        testRealmSAMLPostLoginPage.form().login(bburkeUser);
-        driver.navigate().to(employee2ServletPage.getUriBuilder().clone().path("setCheckRoles").queryParam("roles", roles).build().toURL());
-        WaitUtils.waitUntilElement(By.tagName("body")).text().contains("These roles will be checked:");
-        employee2ServletPage.logout();
-    }
-
     private void assertOnForbiddenPage() {
         waitUntilElement(By.xpath("//body")).is().present();
 

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/adapter/servlet/SAMLServletSessionTimeoutTest.java

@@ -79,21 +79,11 @@ public class SAMLServletSessionTimeoutTest extends AbstractSAMLServletAdapterTes
         return ob;
     }
 
-    private SamlClientBuilder beginAuthenticationAndLogin() {
-        return new SamlClientBuilder()
-                .navigateTo(employee2ServletPage.buildUri())
-                .processSamlResponse(SamlClient.Binding.POST) // Process AuthnResponse
-                .build()
-
-                .login().user(bburkeUser)
-                .build();
-    }
-
     @Test
     public void employee2TestSAMLRefreshingSession() {
         sessionNotOnOrAfter.set(null);
 
-        beginAuthenticationAndLogin()
+        beginAuthenticationAndLogin(employee2ServletPage, SamlClient.Binding.POST)
                 .processSamlResponse(SamlClient.Binding.POST) // Update response with SessionNotOnOrAfter
                     .transformObject(this::addSessionNotOnOrAfter)
                     .build()
@@ -125,7 +115,7 @@ public class SAMLServletSessionTimeoutTest extends AbstractSAMLServletAdapterTes
     public void employee2TestSAMLSessionTimeoutOnBothSides() {
         sessionNotOnOrAfter.set(null);
 
-        beginAuthenticationAndLogin()
+        beginAuthenticationAndLogin(employee2ServletPage, SamlClient.Binding.POST)
                 .processSamlResponse(SamlClient.Binding.POST) // Update response with SessionNotOnOrAfter
                     .transformObject(this::addSessionNotOnOrAfter)
                     .build()
@@ -158,7 +148,7 @@ public class SAMLServletSessionTimeoutTest extends AbstractSAMLServletAdapterTes
         try(AutoCloseable c = new RealmAttributeUpdater(adminClient.realm(REALM_NAME))
                 .updateWith(r -> r.setSsoSessionMaxLifespan(SESSION_LENGTH_IN_SECONDS))
                 .update()) {
-            beginAuthenticationAndLogin()
+            beginAuthenticationAndLogin(employee2ServletPage, SamlClient.Binding.POST)
                     .processSamlResponse(SamlClient.Binding.POST) // Process response
                         .transformObject(ob -> { // Check sessionNotOnOrAfter is present and it has correct value
                             assertThat(ob, Matchers.isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));

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

@@ -32,6 +32,7 @@ public abstract class AbstractBrokerTest extends AbstractInitializedBaseBrokerTe
     public static final String ROLE_MANAGER = "manager";
     public static final String ROLE_FRIENDLY_MANAGER = "friendly-manager";
     public static final String ROLE_USER_DOT_GUIDE = "user.guide";
+    public static final String EMPTY_ATTRIBUTE_ROLE = "empty.attribute.role";
 
     @Page
     ConsentPage consentPage;
@@ -112,11 +113,13 @@ public abstract class AbstractBrokerTest extends AbstractInitializedBaseBrokerTe
         RoleRepresentation friendlyManagerRole = new RoleRepresentation(ROLE_FRIENDLY_MANAGER,null, false);
         RoleRepresentation userRole = new RoleRepresentation(ROLE_USER,null, false);
         RoleRepresentation userGuideRole = new RoleRepresentation(ROLE_USER_DOT_GUIDE,null, false);
+        RoleRepresentation emptyAttributeRole = new RoleRepresentation(EMPTY_ATTRIBUTE_ROLE, null, false);
 
         adminClient.realm(realm).roles().create(managerRole);
         adminClient.realm(realm).roles().create(friendlyManagerRole);
         adminClient.realm(realm).roles().create(userRole);
         adminClient.realm(realm).roles().create(userGuideRole);
+        adminClient.realm(realm).roles().create(emptyAttributeRole);
     }
 
     static void enableUpdateProfileOnFirstLogin(AuthenticationExecutionInfoRepresentation execution, AuthenticationManagementResource flows) {

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

@@ -4,11 +4,19 @@ import org.keycloak.admin.client.resource.UserResource;
 import com.google.common.collect.ImmutableMap;
 import org.keycloak.broker.saml.mappers.AttributeToRoleMapper;
 import org.keycloak.broker.saml.mappers.UserAttributeMapper;
+import org.keycloak.dom.saml.v2.assertion.AssertionType;
+import org.keycloak.dom.saml.v2.assertion.AttributeStatementType;
+import org.keycloak.dom.saml.v2.assertion.AttributeType;
+import org.keycloak.dom.saml.v2.assertion.StatementAbstractType;
 import org.keycloak.dom.saml.v2.protocol.AuthnRequestType;
+import org.keycloak.dom.saml.v2.protocol.ResponseType;
 import org.keycloak.representations.idm.IdentityProviderMapperRepresentation;
 import org.keycloak.representations.idm.RoleRepresentation;
 import org.keycloak.representations.idm.UserRepresentation;
 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.processing.api.saml.v2.request.SAML2Request;
 import org.keycloak.saml.processing.core.saml.v2.common.SAMLDocumentHolder;
 import org.keycloak.testsuite.saml.AbstractSamlTest;
@@ -20,6 +28,8 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Set;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
 import org.hamcrest.Matchers;
 import org.junit.Assert;
 import org.junit.Test;
@@ -30,7 +40,11 @@ import static org.junit.Assert.assertThat;
 import static org.keycloak.testsuite.arquillian.AuthServerTestEnricher.getAuthServerContextRoot;
 import static org.keycloak.testsuite.broker.AbstractBrokerTest.ROLE_MANAGER;
 import static org.keycloak.testsuite.broker.AbstractBrokerTest.ROLE_USER;
+import static org.keycloak.testsuite.saml.RoleMapperTest.ROLE_ATTRIBUTE_NAME;
 import static org.keycloak.testsuite.util.Matchers.isSamlResponse;
+import static org.keycloak.testsuite.util.SamlStreams.assertionsUnencrypted;
+import static org.keycloak.testsuite.util.SamlStreams.attributeStatements;
+import static org.keycloak.testsuite.util.SamlStreams.attributesUnecrypted;
 
 /**
  * Final class as it's not intended to be overriden. Feel free to remove "final" if you really know what you are doing.
@@ -42,6 +56,8 @@ public final class KcSamlBrokerTest extends AbstractAdvancedBrokerTest {
         return KcSamlBrokerConfiguration.INSTANCE;
     }
 
+    private static final String EMPTY_ATTRIBUTE_NAME = "empty.attribute.name";
+
     @Override
     protected Iterable<IdentityProviderMapperRepresentation> createIdentityProviderMappers() {
         IdentityProviderMapperRepresentation attrMapper1 = new IdentityProviderMapperRepresentation();
@@ -80,7 +96,16 @@ public final class KcSamlBrokerTest extends AbstractAdvancedBrokerTest {
                 .put("role", ROLE_USER_DOT_GUIDE)
                 .build());
 
-        return Arrays.asList(new IdentityProviderMapperRepresentation[] { attrMapper1, attrMapper2, attrMapper3, attrMapper4 });
+        IdentityProviderMapperRepresentation attrMapper5 = new IdentityProviderMapperRepresentation();
+        attrMapper5.setName("empty-attribute-to-role-mapper");
+        attrMapper5.setIdentityProviderMapper(AttributeToRoleMapper.PROVIDER_ID);
+        attrMapper5.setConfig(ImmutableMap.<String,String>builder()
+                .put(UserAttributeMapper.ATTRIBUTE_NAME, EMPTY_ATTRIBUTE_NAME)
+                .put(ATTRIBUTE_VALUE, "")
+                .put("role", EMPTY_ATTRIBUTE_ROLE)
+                .build());
+
+        return Arrays.asList(new IdentityProviderMapperRepresentation[] { attrMapper1, attrMapper2, attrMapper3, attrMapper4, attrMapper5 });
     }
 
     // KEYCLOAK-3987
@@ -231,4 +256,64 @@ public final class KcSamlBrokerTest extends AbstractAdvancedBrokerTest {
         Assert.assertThat(samlResponse.getSamlObject(), isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
     }
 
+    @Test
+    public void emptyAttributeToRoleMapperTest() throws ParsingException, ConfigurationException, ProcessingException {
+        createRolesForRealm(bc.consumerRealmName());
+        createRoleMappersForConsumerRealm();
+
+        AuthnRequestType loginRep = SamlClient.createLoginRequestDocument(AbstractSamlTest.SAML_CLIENT_ID_SALES_POST + ".dot/ted", getAuthServerContextRoot() + "/sales-post/saml", null);
+
+        Document doc = SAML2Request.convert(loginRep);
+
+        SAMLDocumentHolder samlResponse = new SamlClientBuilder()
+                .authnRequest(getAuthServerSamlEndpoint(bc.consumerRealmName()), doc, Binding.POST).build()   // Request to consumer IdP
+                .login().idp(bc.getIDPAlias()).build()
+
+                .processSamlResponse(Binding.POST)    // AuthnRequest to producer IdP
+                .targetAttributeSamlRequest()
+                .build()
+
+                .login().user(bc.getUserLogin(), bc.getUserPassword()).build()
+
+                .processSamlResponse(Binding.POST)    // Response from producer IdP
+                    .transformObject(ob -> {
+                        assertThat(ob, org.keycloak.testsuite.util.Matchers.isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
+                        ResponseType resp = (ResponseType) ob;
+
+                        Set<StatementAbstractType> statements = resp.getAssertions().get(0).getAssertion().getStatements();
+
+                        AttributeStatementType attributeType = (AttributeStatementType) statements.stream()
+                                .filter(statement -> statement instanceof AttributeStatementType)
+                                .findFirst().orElse(new AttributeStatementType());
+
+                        AttributeType attr = new AttributeType(EMPTY_ATTRIBUTE_NAME);
+                        attr.addAttributeValue(null);
+
+                        attributeType.addAttribute(new AttributeStatementType.ASTChoiceType(attr));
+                        resp.getAssertions().get(0).getAssertion().addStatement(attributeType);
+
+                        return ob;
+                    })
+                .build()
+
+                // first-broker flow
+                .updateProfile().firstName("a").lastName("b").email(bc.getUserEmail()).username(bc.getUserLogin()).build()
+                .followOneRedirect()
+
+                .getSamlResponse(Binding.POST);       // Response from consumer IdP
+
+        Assert.assertThat(samlResponse, Matchers.notNullValue());
+        Assert.assertThat(samlResponse.getSamlObject(), isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
+
+        Stream<AssertionType> assertionTypeStream = assertionsUnencrypted(samlResponse.getSamlObject());
+        Stream<AttributeType> attributeStatementTypeStream = attributesUnecrypted(attributeStatements(assertionTypeStream));
+        Set<String> attributeValues = attributeStatementTypeStream
+                .filter(a -> a.getName().equals(ROLE_ATTRIBUTE_NAME))
+                .flatMap(a -> a.getAttributeValue().stream())
+                .map(Object::toString)
+                .collect(Collectors.toSet());
+
+        assertThat(attributeValues, hasItems(EMPTY_ATTRIBUTE_ROLE));
+
+    }
 }

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/saml/ProtocolMapperTest.java

@@ -0,0 +1,80 @@
+package org.keycloak.testsuite.saml;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.keycloak.dom.saml.v2.assertion.AssertionType;
+import org.keycloak.dom.saml.v2.assertion.AttributeType;
+import org.keycloak.protocol.saml.mappers.AttributeStatementHelper;
+import org.keycloak.protocol.saml.mappers.HardcodedAttributeMapper;
+import org.keycloak.saml.common.constants.JBossSAMLURIConstants;
+import org.keycloak.saml.processing.core.saml.v2.common.SAMLDocumentHolder;
+import org.keycloak.testsuite.updaters.ClientAttributeUpdater;
+import org.keycloak.testsuite.updaters.ProtocolMappersUpdater;
+import org.keycloak.testsuite.util.Matchers;
+import org.keycloak.testsuite.util.SamlClient;
+import org.keycloak.testsuite.util.SamlClientBuilder;
+
+import java.util.Collections;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static org.hamcrest.CoreMatchers.nullValue;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.Assert.assertThat;
+import static org.keycloak.testsuite.saml.RoleMapperTest.createSamlProtocolMapper;
+import static org.keycloak.testsuite.util.SamlStreams.assertionsUnencrypted;
+import static org.keycloak.testsuite.util.SamlStreams.attributeStatements;
+import static org.keycloak.testsuite.util.SamlStreams.attributesUnecrypted;
+
+/**
+ * @author mhajas
+ */
+public class ProtocolMapperTest extends AbstractSamlTest {
+
+    private ClientAttributeUpdater cau;
+    private ProtocolMappersUpdater pmu;
+
+    @Before
+    public void cleanMappersAndScopes() {
+        this.cau = ClientAttributeUpdater.forClient(adminClient, REALM_NAME, SAML_CLIENT_ID_EMPLOYEE_2)
+                .setDefaultClientScopes(Collections.EMPTY_LIST)
+                .update();
+        this.pmu = cau.protocolMappers()
+                .clear()
+                .update();
+
+        getCleanup(REALM_NAME)
+                .addCleanup(this.cau)
+                .addCleanup(this.pmu);
+    }
+
+    @Test
+    public void hardcodedAttributeMapperWithNullValueTest() throws Exception {
+        pmu.add(
+                createSamlProtocolMapper(HardcodedAttributeMapper.PROVIDER_ID,
+                        AttributeStatementHelper.SAML_ATTRIBUTE_NAME, "HARDCODED_ATTRIBUTE",
+                        AttributeStatementHelper.SAML_ATTRIBUTE_NAMEFORMAT, AttributeStatementHelper.BASIC,
+                        HardcodedAttributeMapper.ATTRIBUTE_VALUE, null
+                )
+        ).update();
+
+
+        SAMLDocumentHolder samlResponse = new SamlClientBuilder()
+                .authnRequest(getAuthServerSamlEndpoint(REALM_NAME), SAML_CLIENT_ID_EMPLOYEE_2, RoleMapperTest.SAML_ASSERTION_CONSUMER_URL_EMPLOYEE_2, SamlClient.Binding.POST)
+                .build()
+                .login().user(bburkeUser).build()
+                .getSamlResponse(SamlClient.Binding.POST);
+
+        assertThat(samlResponse.getSamlObject(), Matchers.isSamlResponse(JBossSAMLURIConstants.STATUS_SUCCESS));
+
+        Stream<AssertionType> assertions = assertionsUnencrypted(samlResponse.getSamlObject());
+        Stream<AttributeType> attributes = attributesUnecrypted(attributeStatements(assertions));
+        Set<Object> attributeValues = attributes
+                .flatMap(a -> a.getAttributeValue().stream())
+                .collect(Collectors.toSet());
+
+        assertThat(attributeValues, hasSize(1));
+        assertThat(attributeValues.iterator().next(), nullValue());
+    }
+}