From 62b3028cf0e33b8e113761450c7dfb1da3672fdb Mon Sep 17 00:00:00 2001 From: Michael Jumper Date: Thu, 14 May 2015 23:10:19 +0000 Subject: [PATCH] GUAC-587: Ensure an AuthenticationProvider is always bound. --- .../AuthenticationProviderFacade.java | 150 ++++++++++++++++++ .../net/basic/extension/ExtensionModule.java | 3 +- 2 files changed, 151 insertions(+), 2 deletions(-) create mode 100644 guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/AuthenticationProviderFacade.java diff --git a/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/AuthenticationProviderFacade.java b/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/AuthenticationProviderFacade.java new file mode 100644 index 000000000..4316fe1c0 --- /dev/null +++ b/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/AuthenticationProviderFacade.java @@ -0,0 +1,150 @@ +/* + * Copyright (C) 2015 Glyptodon LLC + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +package org.glyptodon.guacamole.net.basic.extension; + +import java.lang.reflect.InvocationTargetException; +import org.glyptodon.guacamole.GuacamoleException; +import org.glyptodon.guacamole.net.auth.AuthenticationProvider; +import org.glyptodon.guacamole.net.auth.Credentials; +import org.glyptodon.guacamole.net.auth.UserContext; +import org.glyptodon.guacamole.net.auth.credentials.CredentialsInfo; +import org.glyptodon.guacamole.net.auth.credentials.GuacamoleInsufficientCredentialsException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Provides a safe wrapper around an AuthenticationProvider subclass, such that + * authentication attempts can cleanly fail, and errors can be properly logged, + * even if the AuthenticationProvider cannot be instantiated. + * + * @author Michael Jumper + */ +public class AuthenticationProviderFacade implements AuthenticationProvider { + + /** + * Logger for this class. + */ + private Logger logger = LoggerFactory.getLogger(AuthenticationProviderFacade.class); + + /** + * The underlying authentication provider, or null if the authentication + * provider could not be instantiated. + */ + private final AuthenticationProvider authProvider; + + /** + * Creates a new AuthenticationProviderFacade which delegates all function + * calls to an instance of the given AuthenticationProvider subclass. If + * an instance of the given class cannot be created, creation of this + * facade will still succeed, but its use will result in errors being + * logged, and all authentication attempts will fail. + * + * @param authProviderClass + * The AuthenticationProvider subclass to instantiate. + */ + public AuthenticationProviderFacade(Class authProviderClass) { + + AuthenticationProvider instance = null; + + try { + // Attempt to instantiate the authentication provider + instance = authProviderClass.getConstructor().newInstance(); + } + catch (NoSuchMethodException e) { + logger.error("The authentication extension in use is not properly defined. " + + "Please contact the developers of the extension or, if you " + + "are the developer, turn on debug-level logging."); + logger.debug("AuthenticationProvider is missing a default constructor.", e); + } + catch (SecurityException e) { + logger.error("The Java security mananager is preventing authentication extensions " + + "from being loaded. Please check the configuration of Java or your " + + "servlet container."); + logger.debug("Creation of AuthenticationProvider disallowed by security manager.", e); + } + catch (InstantiationException e) { + logger.error("The authentication extension in use is not properly defined. " + + "Please contact the developers of the extension or, if you " + + "are the developer, turn on debug-level logging."); + logger.debug("AuthenticationProvider cannot be instantiated.", e); + } + catch (IllegalAccessException e) { + logger.error("The authentication extension in use is not properly defined. " + + "Please contact the developers of the extension or, if you " + + "are the developer, turn on debug-level logging."); + logger.debug("Default constructor of AuthenticationProvider is not public.", e); + } + catch (IllegalArgumentException e) { + logger.error("The authentication extension in use is not properly defined. " + + "Please contact the developers of the extension or, if you " + + "are the developer, turn on debug-level logging."); + logger.debug("Default constructor of AuthenticationProvider cannot accept zero arguments.", e); + } + catch (InvocationTargetException e) { + + // Obtain causing error - create relatively-informative stub error if cause is unknown + Throwable cause = e.getCause(); + if (cause == null) + cause = new GuacamoleException("Error encountered during initialization."); + + logger.error("Authentication extension failed to start: {}", cause.getMessage()); + logger.debug("AuthenticationProvider instantiation failed.", e); + + } + + // Associate instance, if any + authProvider = instance; + + } + + @Override + public UserContext getUserContext(Credentials credentials) + throws GuacamoleException { + + // Ignore auth attempts if no auth provider could be loaded + if (authProvider == null) { + logger.warn("Authentication attempt denied because the authentication system could not be loaded. Please for errors earlier in the logs."); + throw new GuacamoleInsufficientCredentialsException("Permission denied.", CredentialsInfo.USERNAME_PASSWORD); + } + + // Delegate to underlying auth provider + return authProvider.getUserContext(credentials); + + } + + @Override + public UserContext updateUserContext(UserContext context, Credentials credentials) + throws GuacamoleException { + + // Ignore auth attempts if no auth provider could be loaded + if (authProvider == null) { + logger.warn("Reauthentication attempt denied because the authentication system could not be loaded. Please for errors earlier in the logs."); + throw new GuacamoleInsufficientCredentialsException("Permission denied.", CredentialsInfo.USERNAME_PASSWORD); + } + + // Delegate to underlying auth provider + return authProvider.updateUserContext(context, credentials); + + } + +} diff --git a/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/ExtensionModule.java b/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/ExtensionModule.java index 99c20e377..aabc06a62 100644 --- a/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/ExtensionModule.java +++ b/guacamole/src/main/java/org/glyptodon/guacamole/net/basic/extension/ExtensionModule.java @@ -22,7 +22,6 @@ package org.glyptodon.guacamole.net.basic.extension; -import com.google.inject.Singleton; import com.google.inject.servlet.ServletModule; import java.io.File; import java.io.FileFilter; @@ -197,7 +196,7 @@ public class ExtensionModule extends ServletModule { // Bind authentication provider logger.debug("Binding AuthenticationProvider \"{}\".", authenticationProvider); - bind(AuthenticationProvider.class).to(authenticationProvider).in(Singleton.class); + bind(AuthenticationProvider.class).toInstance(new AuthenticationProviderFacade(authenticationProvider)); }