Make the loginProcessingUrl configurable for saml2Login()

Fixes gh-7565

https://github.com/spring-projects/spring-security/issues/7565

config/src/main/java/org/springframework/security/config/annotation/web/configurers/saml2/Saml2LoginConfigurer.java

@@ -164,7 +164,10 @@ public final class Saml2LoginConfigurer<B extends HttpSecurityBuilder<B>> extend
 			this.relyingPartyRegistrationRepository = getSharedOrBean(http, RelyingPartyRegistrationRepository.class);
 		}
 
-		Saml2WebSsoAuthenticationFilter webSsoFilter = new Saml2WebSsoAuthenticationFilter(this.relyingPartyRegistrationRepository);
+		Saml2WebSsoAuthenticationFilter webSsoFilter = new Saml2WebSsoAuthenticationFilter(
+				this.relyingPartyRegistrationRepository,
+				this.loginProcessingUrl
+		);
 		setAuthenticationFilter(webSsoFilter);
 		super.loginProcessingUrl(this.loginProcessingUrl);
 

saml2/saml2-service-provider/src/main/java/org/springframework/security/saml2/provider/service/servlet/filter/Saml2WebSsoAuthenticationFilter.java

@@ -44,9 +44,21 @@ public class Saml2WebSsoAuthenticationFilter extends AbstractAuthenticationProce
 	private final RelyingPartyRegistrationRepository relyingPartyRegistrationRepository;
 
 	public Saml2WebSsoAuthenticationFilter(RelyingPartyRegistrationRepository relyingPartyRegistrationRepository) {
-		super(DEFAULT_FILTER_PROCESSES_URI);
+		this(relyingPartyRegistrationRepository, DEFAULT_FILTER_PROCESSES_URI);
+	}
+
+	public Saml2WebSsoAuthenticationFilter(
+			RelyingPartyRegistrationRepository relyingPartyRegistrationRepository,
+			String filterProcessesUrl) {
+		super(filterProcessesUrl);
 		Assert.notNull(relyingPartyRegistrationRepository, "relyingPartyRegistrationRepository cannot be null");
-		this.matcher = new AntPathRequestMatcher(DEFAULT_FILTER_PROCESSES_URI);
+		Assert.hasText(filterProcessesUrl, "filterProcessesUrl must contain a URL pattern");
+		Assert.isTrue(
+				filterProcessesUrl.contains("{registrationId}"),
+				"filterProcessesUrl must contain a {registrationId} match variable"
+		);
+		this.matcher = new AntPathRequestMatcher(filterProcessesUrl);
+		setRequiresAuthenticationRequestMatcher(this.matcher);
 		this.relyingPartyRegistrationRepository = relyingPartyRegistrationRepository;
 		setAllowSessionCreation(true);
 		setSessionAuthenticationStrategy(new ChangeSessionIdAuthenticationStrategy());

saml2/saml2-service-provider/src/test/java/org/springframework/security/saml2/provider/service/servlet/filter/Saml2WebSsoAuthenticationFilterTests.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2002-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.security.saml2.provider.service.servlet.filter;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.security.saml2.provider.service.registration.RelyingPartyRegistrationRepository;
+
+import javax.servlet.http.HttpServletResponse;
+
+import static org.mockito.Mockito.mock;
+
+public class Saml2WebSsoAuthenticationFilterTests {
+
+	private Saml2WebSsoAuthenticationFilter filter;
+	private RelyingPartyRegistrationRepository repository = mock(RelyingPartyRegistrationRepository.class);
+	private MockHttpServletRequest request = new MockHttpServletRequest();
+	private HttpServletResponse response = new MockHttpServletResponse();
+
+	@Rule
+	public ExpectedException exception = ExpectedException.none();
+
+	@Before
+	public void setup() {
+		filter = new Saml2WebSsoAuthenticationFilter(repository);
+		request.setPathInfo("/login/saml2/sso/idp-registration-id");
+		request.setParameter("SAMLResponse", "xml-data-goes-here");
+	}
+
+	@Test
+	public void constructingFilterWithMissingRegistrationIdVariableThenThrowsException() {
+		exception.expect(IllegalArgumentException.class);
+		exception.expectMessage("filterProcessesUrl must contain a {registrationId} match variable");
+		filter = new Saml2WebSsoAuthenticationFilter(repository, "/url/missing/variable");
+	}
+
+	@Test
+	public void constructingFilterWithValidRegistrationIdVariableThenSucceeds() {
+		filter = new Saml2WebSsoAuthenticationFilter(repository, "/url/variable/is/present/{registrationId}");
+	}
+
+	@Test
+	public void requiresAuthenticationWhenHappyPathThenReturnsTrue() {
+		Assert.assertTrue(filter.requiresAuthentication(request, response));
+	}
+
+	@Test
+	public void requiresAuthenticationWhenCustomProcessingUrlThenReturnsTrue() {
+		filter = new Saml2WebSsoAuthenticationFilter(repository, "/some/other/path/{registrationId}");
+		request.setPathInfo("/some/other/path/idp-registration-id");
+		request.setParameter("SAMLResponse", "xml-data-goes-here");
+		Assert.assertTrue(filter.requiresAuthentication(request, response));
+	}
+
+
+}

samples/boot/saml2login/src/integration-test/java/org/springframework/security/samples/Saml2LoginIntegrationTests.java

@@ -51,7 +51,6 @@ import org.springframework.boot.SpringBootConfiguration;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
 import org.springframework.boot.test.context.SpringBootTest;
-import org.springframework.context.annotation.ComponentScan;
 import org.springframework.http.MediaType;
 import org.springframework.security.saml2.provider.service.authentication.Saml2AuthenticationException;
 import org.springframework.test.context.junit4.SpringRunner;
@@ -111,7 +110,6 @@ public class Saml2LoginIntegrationTests {
 
 	@SpringBootConfiguration
 	@EnableAutoConfiguration
-	@ComponentScan(basePackages = "sample")
 	public static class SpringBootApplicationTestConfig {
 
 	}

samples/javaconfig/saml2login/src/main/java/org/springframework/security/samples/config/SecurityConfig.java

@@ -76,6 +76,7 @@ public class SecurityConfig extends WebSecurityConfigurerAdapter {
 							getSaml2AuthenticationConfiguration()
 					)
 				)
+				.loginProcessingUrl("/sample/jc/saml2/sso/{registrationId}")
 		;
 		// @formatter:on
 	}

samples/javaconfig/saml2login/src/test/java/org/springframework/security/samples/config/SecurityConfigTests.java

@@ -15,17 +15,46 @@
  */
 package org.springframework.security.samples.config;
 
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.security.saml2.provider.service.servlet.filter.Saml2WebSsoAuthenticationFilter;
+import org.springframework.security.web.FilterChainProxy;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.util.ReflectionTestUtils;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import java.util.List;
+import javax.servlet.Filter;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @ContextConfiguration(classes = SecurityConfig.class)
 public class SecurityConfigTests {
 
+	@Autowired
+	ApplicationContext context;
+
 	@Test
 	public void securityConfigurationLoads() {
 	}
+
+	@Test
+	public void filterWhenLoginProcessingUrlIsSetInJavaConfigThenTheFilterHasIt() {
+		FilterChainProxy filterChain = context.getBean(FilterChainProxy.class);
+		Assert.assertNotNull(filterChain);
+		final List<Filter> filters = filterChain.getFilters("/sample/jc/saml2/sso/test-id");
+		Assert.assertNotNull(filters);
+		Saml2WebSsoAuthenticationFilter filter = (Saml2WebSsoAuthenticationFilter) filters
+				.stream()
+				.filter(
+						f -> f instanceof Saml2WebSsoAuthenticationFilter
+				)
+				.findFirst()
+				.get();
+		final Object matcher = ReflectionTestUtils.getField(filter, "requiresAuthenticationRequestMatcher");
+		final Object pattern = ReflectionTestUtils.getField(matcher, "pattern");
+		Assert.assertEquals("loginProcessingUrl mismatch", "/sample/jc/saml2/sso/{registrationId}", pattern);
+	}
 }