Support Client and RoleMapping in custom Realms (#50950)

Previously custom realms were limited in what services and components
they had easy access to. It was possible to work around this because a
security extension is packaged within a Plugin, so there were ways to
store this components in static/SetOnce variables and access them from
the realm, but those techniques were fragile, undocumented and
difficult to discover.

This change includes key services as an argument to most of the methods
on SecurityExtension so that custom realm / role provider authors can
have easy access to them.

Backport of: #50534

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/SecurityExtension.java

@@ -7,10 +7,15 @@
 
 import org.apache.lucene.util.SPIClassIterator;
 import org.elasticsearch.action.ActionListener;
+import org.elasticsearch.client.Client;
+import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.watcher.ResourceWatcherService;
 import org.elasticsearch.xpack.core.security.authc.AuthenticationFailureHandler;
 import org.elasticsearch.xpack.core.security.authc.Realm;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.core.security.authz.AuthorizationEngine;
 import org.elasticsearch.xpack.core.security.authz.RoleDescriptor;
 import org.elasticsearch.xpack.core.security.authz.store.RoleRetrievalResult;
@@ -28,16 +33,36 @@
  */
 public interface SecurityExtension {
 
+    /**
+     * This interface provides access to components (clients and services) that may be used
+     * within custom realms and role providers.
+     */
+    interface SecurityComponents {
+        /** Global settings for the current node */
+        Settings settings();
+        /** Provides access to key filesystem paths */
+        Environment environment();
+        /** An internal client for retrieving information/data from this cluster */
+        Client client();
+        /** The Elasticsearch thread pools */
+        ThreadPool threadPool();
+        /** Provides the ability to monitor files for changes */
+        ResourceWatcherService resourceWatcherService();
+        /** Access to listen to changes in cluster state and settings  */
+        ClusterService clusterService();
+        /** Provides support for mapping users' roles from groups and metadata */
+        UserRoleMapper roleMapper();
+    }
     /**
      * Returns authentication realm implementations added by this extension.
      *
      * The key of the returned {@link Map} is the type name of the realm, and the value
      * is a {@link Realm.Factory} which will construct
      * that realm for use in authentication when that realm type is configured.
      *
-     * @param resourceWatcherService Use to watch configuration files for changes
+     * @param components Access to components that may be used to build realms
      */
-    default Map<String, Realm.Factory> getRealms(ResourceWatcherService resourceWatcherService) {
+    default Map<String, Realm.Factory> getRealms(SecurityComponents components) {
         return Collections.emptyMap();
     }
 
@@ -46,8 +71,10 @@ default Map<String, Realm.Factory> getRealms(ResourceWatcherService resourceWatc
      *
      * Only one installed extension may have an authentication failure handler. If more than
      * one extension returns a non-null handler, an error is raised.
+     *
+     * @param components Access to components that may be used to build the handler
      */
-    default AuthenticationFailureHandler getAuthenticationFailureHandler() {
+    default AuthenticationFailureHandler getAuthenticationFailureHandler(SecurityComponents components) {
         return null;
     }
 
@@ -72,11 +99,10 @@ default AuthenticationFailureHandler getAuthenticationFailureHandler() {
      *
      * By default, an empty list is returned.
      *
-     * @param settings The configured settings for the node
-     * @param resourceWatcherService Use to watch configuration files for changes
+     * @param components Access to components that may be used to build roles
      */
     default List<BiConsumer<Set<String>, ActionListener<RoleRetrievalResult>>>
-        getRolesProviders(Settings settings, ResourceWatcherService resourceWatcherService) {
+        getRolesProviders(SecurityComponents components) {
         return Collections.emptyList();
     }
 

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/CachingRealm.java → x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authc/support/CachingRealm.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.security.authc.support;
+package org.elasticsearch.xpack.core.security.authc.support;
 
 import org.elasticsearch.xpack.core.security.authc.Realm;
 

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/UserRoleMapper.java → x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authc/support/UserRoleMapper.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.security.authc.support;
+package org.elasticsearch.xpack.core.security.authc.support;
 
 import com.unboundid.ldap.sdk.DN;
 import com.unboundid.ldap.sdk.LDAPException;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/Security.java

@@ -232,6 +232,7 @@
 import org.elasticsearch.xpack.security.rest.action.user.RestHasPrivilegesAction;
 import org.elasticsearch.xpack.security.rest.action.user.RestPutUserAction;
 import org.elasticsearch.xpack.security.rest.action.user.RestSetEnabledAction;
+import org.elasticsearch.xpack.security.support.ExtensionComponents;
 import org.elasticsearch.xpack.security.support.SecurityIndexManager;
 import org.elasticsearch.xpack.security.support.SecurityStatusChangeListener;
 import org.elasticsearch.xpack.security.transport.SecurityHttpSettings;
@@ -436,10 +437,12 @@ Collection<Object> createComponents(Client client, ThreadPool threadPool, Cluste
         final AnonymousUser anonymousUser = new AnonymousUser(settings);
         final ReservedRealm reservedRealm = new ReservedRealm(env, settings, nativeUsersStore,
                 anonymousUser, securityIndex.get(), threadPool);
+        final SecurityExtension.SecurityComponents extensionComponents = new ExtensionComponents(env, client, clusterService,
+            resourceWatcherService, nativeRoleMappingStore);
         Map<String, Realm.Factory> realmFactories = new HashMap<>(InternalRealms.getFactories(threadPool, resourceWatcherService,
                 getSslService(), nativeUsersStore, nativeRoleMappingStore, securityIndex.get()));
         for (SecurityExtension extension : securityExtensions) {
-            Map<String, Realm.Factory> newRealms = extension.getRealms(resourceWatcherService);
+            Map<String, Realm.Factory> newRealms = extension.getRealms(extensionComponents);
             for (Map.Entry<String, Realm.Factory> entry : newRealms.entrySet()) {
                 if (realmFactories.put(entry.getKey(), entry.getValue()) != null) {
                     throw new IllegalArgumentException("Realm type [" + entry.getKey() + "] is already registered");
@@ -465,7 +468,7 @@ Collection<Object> createComponents(Client client, ThreadPool threadPool, Cluste
         final ReservedRolesStore reservedRolesStore = new ReservedRolesStore();
         List<BiConsumer<Set<String>, ActionListener<RoleRetrievalResult>>> rolesProviders = new ArrayList<>();
         for (SecurityExtension extension : securityExtensions) {
-            rolesProviders.addAll(extension.getRolesProviders(settings, resourceWatcherService));
+            rolesProviders.addAll(extension.getRolesProviders(extensionComponents));
         }
 
         final ApiKeyService apiKeyService = new ApiKeyService(settings, Clock.systemUTC(), client, getLicenseState(), securityIndex.get(),
@@ -481,7 +484,7 @@ Collection<Object> createComponents(Client client, ThreadPool threadPool, Cluste
         getLicenseState().addListener(allRolesStore::invalidateAll);
         getLicenseState().addListener(new SecurityStatusChangeListener(getLicenseState()));
 
-        final AuthenticationFailureHandler failureHandler = createAuthenticationFailureHandler(realms);
+        final AuthenticationFailureHandler failureHandler = createAuthenticationFailureHandler(realms, extensionComponents);
         authcService.set(new AuthenticationService(settings, realms, auditTrailService, failureHandler, threadPool,
                 anonymousUser, tokenService, apiKeyService));
         components.add(authcService.get());
@@ -539,11 +542,12 @@ private AuthorizationEngine getAuthorizationEngine() {
         return authorizationEngine;
     }
 
-    private AuthenticationFailureHandler createAuthenticationFailureHandler(final Realms realms) {
+    private AuthenticationFailureHandler createAuthenticationFailureHandler(final Realms realms,
+                                                                            final SecurityExtension.SecurityComponents components) {
         AuthenticationFailureHandler failureHandler = null;
         String extensionName = null;
         for (SecurityExtension extension : securityExtensions) {
-            AuthenticationFailureHandler extensionFailureHandler = extension.getAuthenticationFailureHandler();
+            AuthenticationFailureHandler extensionFailureHandler = extension.getAuthenticationFailureHandler(components);
             if (extensionFailureHandler != null && failureHandler != null) {
                 throw new IllegalStateException("Extensions [" + extensionName + "] and [" + extension.toString() + "] "
                         + "both set an authentication failure handler");

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/action/realm/TransportClearRealmCacheAction.java

@@ -20,7 +20,7 @@
 import org.elasticsearch.xpack.core.security.authc.Realm;
 import org.elasticsearch.xpack.security.authc.AuthenticationService;
 import org.elasticsearch.xpack.security.authc.Realms;
-import org.elasticsearch.xpack.security.authc.support.CachingRealm;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 
 import java.io.IOException;
 import java.util.List;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/kerberos/KerberosRealm.java

@@ -21,9 +21,9 @@
 import org.elasticsearch.xpack.core.security.authc.RealmConfig;
 import org.elasticsearch.xpack.core.security.authc.kerberos.KerberosRealmSettings;
 import org.elasticsearch.xpack.core.security.user.User;
-import org.elasticsearch.xpack.security.authc.support.CachingRealm;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 import org.elasticsearch.xpack.security.authc.support.DelegatedAuthorizationSupport;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.authc.support.mapper.NativeRoleMappingStore;
 import org.ietf.jgss.GSSException;
 

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/ldap/LdapRealm.java

@@ -35,8 +35,8 @@
 import org.elasticsearch.xpack.security.authc.ldap.support.SessionFactory;
 import org.elasticsearch.xpack.security.authc.support.CachingUsernamePasswordRealm;
 import org.elasticsearch.xpack.security.authc.support.DelegatedAuthorizationSupport;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper.UserData;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper.UserData;
 import org.elasticsearch.xpack.security.authc.support.mapper.CompositeRoleMapper;
 import org.elasticsearch.xpack.security.authc.support.mapper.NativeRoleMappingStore;
 

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/oidc/OpenIdConnectRealm.java

@@ -44,7 +44,7 @@
 import org.elasticsearch.xpack.core.ssl.SSLService;
 import org.elasticsearch.xpack.security.authc.TokenService;
 import org.elasticsearch.xpack.security.authc.support.DelegatedAuthorizationSupport;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 
 import java.net.URI;
 import java.net.URISyntaxException;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/pki/PkiRealm.java

@@ -32,9 +32,9 @@
 import org.elasticsearch.xpack.core.ssl.SSLConfigurationSettings;
 import org.elasticsearch.xpack.security.authc.BytesKey;
 import org.elasticsearch.xpack.security.authc.TokenService;
-import org.elasticsearch.xpack.security.authc.support.CachingRealm;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 import org.elasticsearch.xpack.security.authc.support.DelegatedAuthorizationSupport;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.authc.support.mapper.CompositeRoleMapper;
 import org.elasticsearch.xpack.security.authc.support.mapper.NativeRoleMappingStore;
 

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/saml/SamlRealm.java

@@ -50,7 +50,7 @@
 import org.elasticsearch.xpack.security.authc.Realms;
 import org.elasticsearch.xpack.security.authc.TokenService;
 import org.elasticsearch.xpack.security.authc.support.DelegatedAuthorizationSupport;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.opensaml.core.criterion.EntityIdCriterion;
 import org.opensaml.saml.common.xml.SAMLConstants;
 import org.opensaml.saml.criterion.EntityRoleCriterion;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/CachingUsernamePasswordRealm.java

@@ -17,6 +17,7 @@
 import org.elasticsearch.xpack.core.security.authc.AuthenticationResult;
 import org.elasticsearch.xpack.core.security.authc.AuthenticationToken;
 import org.elasticsearch.xpack.core.security.authc.RealmConfig;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 import org.elasticsearch.xpack.core.security.authc.support.CachingUsernamePasswordRealmSettings;
 import org.elasticsearch.xpack.core.security.authc.support.Hasher;
 import org.elasticsearch.xpack.core.security.authc.support.UsernamePasswordToken;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/DnRoleMapper.java

@@ -35,7 +35,9 @@
 import org.elasticsearch.watcher.ResourceWatcherService;
 import org.elasticsearch.xpack.core.XPackPlugin;
 import org.elasticsearch.xpack.core.security.authc.RealmConfig;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 import org.elasticsearch.xpack.core.security.authc.support.DnRoleMapperSettings;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.unmodifiableMap;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/mapper/CompositeRoleMapper.java

@@ -15,9 +15,9 @@
 import org.elasticsearch.action.support.GroupedActionListener;
 import org.elasticsearch.watcher.ResourceWatcherService;
 import org.elasticsearch.xpack.core.security.authc.RealmConfig;
-import org.elasticsearch.xpack.security.authc.support.CachingRealm;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
 import org.elasticsearch.xpack.security.authc.support.DnRoleMapper;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 
 /**
  * A {@link UserRoleMapper} that composes one or more <i>delegate</i> role-mappers.

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/support/mapper/NativeRoleMappingStore.java

@@ -37,8 +37,8 @@
 import org.elasticsearch.xpack.core.security.authc.support.mapper.expressiondsl.ExpressionModel;
 import org.elasticsearch.xpack.core.security.client.SecurityClient;
 import org.elasticsearch.xpack.core.security.index.RestrictedIndicesNames;
-import org.elasticsearch.xpack.security.authc.support.CachingRealm;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.CachingRealm;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.support.SecurityIndexManager;
 
 import java.io.IOException;

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/support/ExtensionComponents.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+package org.elasticsearch.xpack.security.support;
+
+import org.elasticsearch.client.Client;
+import org.elasticsearch.cluster.service.ClusterService;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.threadpool.ThreadPool;
+import org.elasticsearch.watcher.ResourceWatcherService;
+import org.elasticsearch.xpack.core.security.SecurityExtension;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
+
+/**
+ * Immutable implementation of {@link SecurityExtension.SecurityComponents}.
+ */
+public final class ExtensionComponents implements SecurityExtension.SecurityComponents {
+    private final Environment environment;
+    private final Client client;
+    private final ClusterService clusterService;
+    private final ResourceWatcherService resourceWatcherService;
+    private final UserRoleMapper roleMapper;
+
+    public ExtensionComponents(Environment environment, Client client, ClusterService clusterService,
+                               ResourceWatcherService resourceWatcherService, UserRoleMapper roleMapper) {
+        this.environment = environment;
+        this.client = client;
+        this.clusterService = clusterService;
+        this.resourceWatcherService = resourceWatcherService;
+        this.roleMapper = roleMapper;
+    }
+
+    @Override
+    public Settings settings() {
+        return environment.settings();
+    }
+
+    @Override
+    public Environment environment() {
+        return environment;
+    }
+
+    @Override
+    public Client client() {
+        return client;
+    }
+
+    @Override
+    public ThreadPool threadPool() {
+        return client.threadPool();
+    }
+
+    @Override
+    public ResourceWatcherService resourceWatcherService() {
+        return resourceWatcherService;
+    }
+
+    @Override
+    public ClusterService clusterService() {
+        return clusterService;
+    }
+
+    @Override
+    public UserRoleMapper roleMapper() {
+        return roleMapper;
+    }
+}

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/SecurityTests.java

@@ -89,7 +89,7 @@ public static class DummyExtension implements SecurityExtension {
         }
 
         @Override
-        public Map<String, Realm.Factory> getRealms(ResourceWatcherService resourceWatcherService) {
+        public Map<String, Realm.Factory> getRealms(SecurityComponents components) {
             return Collections.singletonMap(realmType, config -> null);
         }
     }

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/action/oidc/TransportOpenIdConnectLogoutActionTests.java

@@ -51,7 +51,7 @@
 import org.elasticsearch.xpack.security.authc.TokenService;
 import org.elasticsearch.xpack.security.authc.oidc.OpenIdConnectRealm;
 import org.elasticsearch.xpack.security.authc.oidc.OpenIdConnectTestCase;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.support.SecurityIndexManager;
 import org.junit.After;
 import org.junit.Before;

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/action/saml/TransportSamlLogoutActionTests.java

@@ -61,7 +61,7 @@
 import org.elasticsearch.xpack.security.authc.saml.SamlRealm;
 import org.elasticsearch.xpack.security.authc.saml.SamlRealmTests;
 import org.elasticsearch.xpack.security.authc.saml.SamlTestCase;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.support.SecurityIndexManager;
 import org.junit.After;
 import org.junit.Before;

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/kerberos/KerberosRealmCacheTests.java

@@ -12,7 +12,7 @@
 import org.elasticsearch.xpack.core.security.authc.AuthenticationResult;
 import org.elasticsearch.xpack.core.security.authc.kerberos.KerberosRealmSettings;
 import org.elasticsearch.xpack.core.security.user.User;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper.UserData;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper.UserData;
 import org.ietf.jgss.GSSException;
 
 import javax.security.auth.login.LoginException;

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/kerberos/KerberosRealmTestCase.java

@@ -27,7 +27,7 @@
 import org.elasticsearch.xpack.core.security.authc.kerberos.KerberosRealmSettings;
 import org.elasticsearch.xpack.core.security.support.Exceptions;
 import org.elasticsearch.xpack.core.security.user.User;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper;
 import org.elasticsearch.xpack.security.authc.support.mapper.NativeRoleMappingStore;
 import org.elasticsearch.xpack.security.support.SecurityIndexManager;
 import org.junit.After;

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/kerberos/KerberosRealmTests.java

@@ -22,7 +22,7 @@
 import org.elasticsearch.xpack.core.security.authc.support.UsernamePasswordToken;
 import org.elasticsearch.xpack.core.security.user.User;
 import org.elasticsearch.xpack.security.authc.support.MockLookupRealm;
-import org.elasticsearch.xpack.security.authc.support.UserRoleMapper.UserData;
+import org.elasticsearch.xpack.core.security.authc.support.UserRoleMapper.UserData;
 import org.ietf.jgss.GSSException;
 
 import javax.security.auth.login.LoginException;