Support Showing One Part of Login Page

Closes gh-17901

config/src/test/java/org/springframework/security/config/annotation/web/configurers/FormLoginConfigurerTests.java

@@ -402,7 +402,7 @@ public class FormLoginConfigurerTests {
 		UserDetails user = PasswordEncodedUser.user();
 		this.mockMvc.perform(get("/profile").with(user(user)))
 			.andExpect(status().is3xxRedirection())
-			.andExpect(redirectedUrl("http://localhost/login"));
+			.andExpect(redirectedUrl("http://localhost/login?authority=FACTOR_PASSWORD"));
 		this.mockMvc
 			.perform(post("/ott/generate").param("username", "rod")
 				.with(user(user))
@@ -418,11 +418,11 @@ public class FormLoginConfigurerTests {
 		user = PasswordEncodedUser.withUserDetails(user).authorities("profile:read", "FACTOR_OTT").build();
 		this.mockMvc.perform(get("/profile").with(user(user)))
 			.andExpect(status().is3xxRedirection())
-			.andExpect(redirectedUrl("http://localhost/login"));
+			.andExpect(redirectedUrl("http://localhost/login?authority=FACTOR_PASSWORD"));
 		user = PasswordEncodedUser.withUserDetails(user).authorities("profile:read", "FACTOR_PASSWORD").build();
 		this.mockMvc.perform(get("/profile").with(user(user)))
 			.andExpect(status().is3xxRedirection())
-			.andExpect(redirectedUrl("http://localhost/login"));
+			.andExpect(redirectedUrl("http://localhost/login?authority=FACTOR_OTT"));
 		user = PasswordEncodedUser.withUserDetails(user)
 			.authorities("profile:read", "FACTOR_PASSWORD", "FACTOR_OTT")
 			.build();
@@ -438,7 +438,7 @@ public class FormLoginConfigurerTests {
 		this.mockMvc.perform(get("/login")).andExpect(status().isOk());
 		this.mockMvc.perform(get("/profile").with(SecurityMockMvcRequestPostProcessors.x509("rod.cer")))
 			.andExpect(status().is3xxRedirection())
-			.andExpect(redirectedUrl("http://localhost/login"));
+			.andExpect(redirectedUrl("http://localhost/login?authority=FACTOR_PASSWORD"));
 		this.mockMvc
 			.perform(post("/login").param("username", "rod")
 				.param("password", "password")

core/src/main/java/org/springframework/security/core/GrantedAuthority.java

@@ -31,6 +31,8 @@ import org.springframework.security.authorization.AuthorizationManager;
  */
 public interface GrantedAuthority extends Serializable {
 
+	String MISSING_AUTHORITIES_ATTRIBUTE = GrantedAuthority.class + ".missingAuthorities";
+
 	/**
 	 * If the <code>GrantedAuthority</code> can be represented as a <code>String</code>
 	 * and that <code>String</code> is sufficient in precision to be relied upon for an

web/src/main/java/org/springframework/security/web/access/DelegatingMissingAuthorityAccessDeniedHandler.java

@@ -91,14 +91,19 @@ public final class DelegatingMissingAuthorityAccessDeniedHandler implements Acce
 	public void handle(HttpServletRequest request, HttpServletResponse response, AccessDeniedException denied)
 			throws IOException, ServletException {
 		Collection<GrantedAuthority> authorities = missingAuthorities(denied);
-		AuthenticationEntryPoint entryPoint = entryPoint(authorities);
-		if (entryPoint == null) {
-			this.defaultAccessDeniedHandler.handle(request, response, denied);
+		for (GrantedAuthority needed : authorities) {
+			AuthenticationEntryPoint entryPoint = this.entryPoints.get(needed.getAuthority());
+			if (entryPoint == null) {
+				continue;
+			}
+			this.requestCache.saveRequest(request, response);
+			request.setAttribute(GrantedAuthority.MISSING_AUTHORITIES_ATTRIBUTE, List.of(needed));
+			String message = String.format("Missing Authorities %s", List.of(needed));
+			AuthenticationException ex = new InsufficientAuthenticationException(message, denied);
+			entryPoint.commence(request, response, ex);
 			return;
 		}
-		this.requestCache.saveRequest(request, response);
-		AuthenticationException ex = new InsufficientAuthenticationException("missing authorities", denied);
-		entryPoint.commence(request, response, ex);
+		this.defaultAccessDeniedHandler.handle(request, response, denied);
 	}
 
 	/**
@@ -121,17 +126,6 @@ public final class DelegatingMissingAuthorityAccessDeniedHandler implements Acce
 		this.requestCache = requestCache;
 	}
 
-	private @Nullable AuthenticationEntryPoint entryPoint(Collection<GrantedAuthority> authorities) {
-		for (GrantedAuthority needed : authorities) {
-			AuthenticationEntryPoint entryPoint = this.entryPoints.get(needed.getAuthority());
-			if (entryPoint == null) {
-				continue;
-			}
-			return entryPoint;
-		}
-		return null;
-	}
-
 	private Collection<GrantedAuthority> missingAuthorities(AccessDeniedException ex) {
 		AuthorizationDeniedException denied = findAuthorizationDeniedException(ex);
 		if (denied == null) {

web/src/main/java/org/springframework/security/web/authentication/LoginUrlAuthenticationEntryPoint.java

@@ -17,6 +17,7 @@
 package org.springframework.security.web.authentication;
 
 import java.io.IOException;
+import java.util.Collection;
 
 import jakarta.servlet.RequestDispatcher;
 import jakarta.servlet.ServletException;
@@ -30,6 +31,7 @@ import org.jspecify.annotations.Nullable;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.core.log.LogMessage;
 import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.web.AuthenticationEntryPoint;
 import org.springframework.security.web.DefaultRedirectStrategy;
 import org.springframework.security.web.PortMapper;
@@ -40,6 +42,7 @@ import org.springframework.security.web.util.RedirectUrlBuilder;
 import org.springframework.security.web.util.UrlUtils;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
+import org.springframework.web.util.UriComponentsBuilder;
 
 /**
  * Used by the {@link ExceptionTranslationFilter} to commence a form login authentication
@@ -109,6 +112,12 @@ public class LoginUrlAuthenticationEntryPoint implements AuthenticationEntryPoin
 	 */
 	protected String determineUrlToUseForThisRequest(HttpServletRequest request, HttpServletResponse response,
 			AuthenticationException exception) {
+		Object value = request.getAttribute(GrantedAuthority.MISSING_AUTHORITIES_ATTRIBUTE);
+		if (value instanceof Collection<?> authorities) {
+			return UriComponentsBuilder.fromUriString(getLoginFormUrl())
+				.queryParam("authority", authorities)
+				.toUriString();
+		}
 		return getLoginFormUrl();
 	}
 

web/src/main/java/org/springframework/security/web/authentication/ui/DefaultLoginPageGeneratingFilter.java

@@ -18,9 +18,12 @@ package org.springframework.security.web.authentication.ui;
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 import java.util.function.Function;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
 import jakarta.servlet.FilterChain;
@@ -31,10 +34,14 @@ import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import org.jspecify.annotations.Nullable;
 
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.context.SecurityContextHolderStrategy;
 import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
 import org.springframework.security.web.authentication.rememberme.AbstractRememberMeServices;
 import org.springframework.util.Assert;
 import org.springframework.web.filter.GenericFilterBean;
+import org.springframework.web.util.UriComponentsBuilder;
 
 /**
  * For internal use with namespace configuration in the case where a user doesn't
@@ -78,6 +85,8 @@ public class DefaultLoginPageGeneratingFilter extends GenericFilterBean {
 
 	private @Nullable String rememberMeParameter;
 
+	private final Collection<String> allowedParameters = List.of("authority");
+
 	@SuppressWarnings("NullAway.Init")
 	private Map<String, String> oauth2AuthenticationUrlToClientName;
 
@@ -223,16 +232,43 @@ public class DefaultLoginPageGeneratingFilter extends GenericFilterBean {
 		String errorMsg = "Invalid credentials";
 		String contextPath = request.getContextPath();
 
-		return HtmlTemplates.fromTemplate(LOGIN_PAGE_TEMPLATE)
+		HtmlTemplates.Builder builder = HtmlTemplates.fromTemplate(LOGIN_PAGE_TEMPLATE)
 			.withRawHtml("contextPath", contextPath)
-			.withRawHtml("javaScript", renderJavaScript(request, contextPath))
-			.withRawHtml("formLogin", renderFormLogin(request, loginError, logoutSuccess, contextPath, errorMsg))
-			.withRawHtml("oneTimeTokenLogin",
-					renderOneTimeTokenLogin(request, loginError, logoutSuccess, contextPath, errorMsg))
-			.withRawHtml("oauth2Login", renderOAuth2Login(loginError, logoutSuccess, errorMsg, contextPath))
-			.withRawHtml("saml2Login", renderSaml2Login(loginError, logoutSuccess, errorMsg, contextPath))
-			.withRawHtml("passkeyLogin", renderPasskeyLogin())
-			.render();
+			.withRawHtml("javaScript", "")
+			.withRawHtml("formLogin", "")
+			.withRawHtml("oneTimeTokenLogin", "")
+			.withRawHtml("oauth2Login", "")
+			.withRawHtml("saml2Login", "")
+			.withRawHtml("passkeyLogin", "");
+
+		Predicate<String> wantsAuthority = wantsAuthority(request);
+		if (wantsAuthority.test("FACTOR_WEBAUTHN")) {
+			builder.withRawHtml("javaScript", renderJavaScript(request, contextPath))
+				.withRawHtml("passkeyLogin", renderPasskeyLogin());
+		}
+		if (wantsAuthority.test("FACTOR_PASSWORD")) {
+			builder.withRawHtml("formLogin",
+					renderFormLogin(request, loginError, logoutSuccess, contextPath, errorMsg));
+		}
+		if (wantsAuthority.test("FACTOR_OTT")) {
+			builder.withRawHtml("oneTimeTokenLogin",
+					renderOneTimeTokenLogin(request, loginError, logoutSuccess, contextPath, errorMsg));
+		}
+		if (wantsAuthority.test("FACTOR_AUTHORIZATION_CODE")) {
+			builder.withRawHtml("oauth2Login", renderOAuth2Login(loginError, logoutSuccess, errorMsg, contextPath));
+		}
+		if (wantsAuthority.test("FACTOR_SAML_RESPONSE")) {
+			builder.withRawHtml("saml2Login", renderSaml2Login(loginError, logoutSuccess, errorMsg, contextPath));
+		}
+		return builder.render();
+	}
+
+	private Predicate<String> wantsAuthority(HttpServletRequest request) {
+		String[] authorities = request.getParameterValues("authority");
+		if (authorities == null) {
+			return (authority) -> true;
+		}
+		return List.of(authorities)::contains;
 	}
 
 	private String renderJavaScript(HttpServletRequest request, String contextPath) {
@@ -413,10 +449,19 @@ public class DefaultLoginPageGeneratingFilter extends GenericFilterBean {
 		if (request.getQueryString() != null) {
 			uri += "?" + request.getQueryString();
 		}
+		UriComponentsBuilder addAllowed = UriComponentsBuilder.fromUriString(url);
+		for (String parameter : this.allowedParameters) {
+			String[] values = request.getParameterValues(parameter);
+			if (values != null) {
+				for (String value : values) {
+					addAllowed.queryParam(parameter, value);
+				}
+			}
+		}
 		if ("".equals(request.getContextPath())) {
-			return uri.equals(url);
+			return uri.equals(addAllowed.toUriString());
 		}
-		return uri.equals(request.getContextPath() + url);
+		return uri.equals(request.getContextPath() + addAllowed.toUriString());
 	}
 
 	private static final String CSRF_HEADERS = """

web/src/test/java/org/springframework/security/web/authentication/DefaultLoginPageGeneratingFilterTests.java

@@ -28,6 +28,7 @@ import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.security.authentication.BadCredentialsException;
 import org.springframework.security.web.WebAttributes;
 import org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter;
+import org.springframework.security.web.servlet.TestMockHttpServletRequests;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.mock;
@@ -191,6 +192,60 @@ public class DefaultLoginPageGeneratingFilterTests {
 				""");
 	}
 
+	@Test
+	public void generateWhenOneTimeTokenRequestedThenOttForm() throws Exception {
+		DefaultLoginPageGeneratingFilter filter = new DefaultLoginPageGeneratingFilter();
+		filter.setLoginPageUrl(DefaultLoginPageGeneratingFilter.DEFAULT_LOGIN_PAGE_URL);
+		filter.setFormLoginEnabled(true);
+		filter.setOneTimeTokenEnabled(true);
+		filter.setOneTimeTokenGenerationUrl("/ott/authenticate");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		filter.doFilter(TestMockHttpServletRequests.get("/login?authority=FACTOR_OTT").build(), response, this.chain);
+		assertThat(response.getContentAsString()).contains("Request a One-Time Token");
+		assertThat(response.getContentAsString()).contains("""
+				      <form id="ott-form" class="login-form" method="post" action="/ott/authenticate">
+				        <h2>Request a One-Time Token</h2>
+
+				        <p>
+				          <label for="ott-username" class="screenreader">Username</label>
+				          <input type="text" id="ott-username" name="username" placeholder="Username" required>
+				        </p>
+
+				        <button class="primary" type="submit" form="ott-form">Send Token</button>
+				      </form>
+				""");
+		assertThat(response.getContentAsString()).doesNotContain("Password");
+	}
+
+	@Test
+	public void generateWhenTwoAuthoritiesRequestedThenBothForms() throws Exception {
+		DefaultLoginPageGeneratingFilter filter = new DefaultLoginPageGeneratingFilter();
+		filter.setLoginPageUrl(DefaultLoginPageGeneratingFilter.DEFAULT_LOGIN_PAGE_URL);
+		filter.setFormLoginEnabled(true);
+		filter.setUsernameParameter("username");
+		filter.setPasswordParameter("password");
+		filter.setOneTimeTokenEnabled(true);
+		filter.setOneTimeTokenGenerationUrl("/ott/authenticate");
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		filter.doFilter(
+				TestMockHttpServletRequests.get("/login?authority=FACTOR_OTT&authority=FACTOR_PASSWORD").build(),
+				response, this.chain);
+		assertThat(response.getContentAsString()).contains("Request a One-Time Token");
+		assertThat(response.getContentAsString()).contains("""
+				      <form id="ott-form" class="login-form" method="post" action="/ott/authenticate">
+				        <h2>Request a One-Time Token</h2>
+
+				        <p>
+				          <label for="ott-username" class="screenreader">Username</label>
+				          <input type="text" id="ott-username" name="username" placeholder="Username" required>
+				        </p>
+
+				        <button class="primary" type="submit" form="ott-form">Send Token</button>
+				      </form>
+				""");
+		assertThat(response.getContentAsString()).contains("Password");
+	}
+
 	@Test
 	void generatesThenRenders() throws ServletException, IOException {
 		DefaultLoginPageGeneratingFilter filter = new DefaultLoginPageGeneratingFilter(