GUAC-1101: Move connection logic into GuacamoleSocketService, with policy-specific implementations.

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/MySQLAuthenticationProvider.java

@@ -39,11 +39,13 @@ import org.glyptodon.guacamole.net.auth.UserContext;
 import net.sourceforge.guacamole.net.auth.mysql.dao.UserMapper;
 import net.sourceforge.guacamole.net.auth.mysql.properties.MySQLGuacamoleProperties;
 import net.sourceforge.guacamole.net.auth.mysql.service.ConnectionService;
+import net.sourceforge.guacamole.net.auth.mysql.service.GuacamoleSocketService;
 import net.sourceforge.guacamole.net.auth.mysql.service.PasswordEncryptionService;
 import net.sourceforge.guacamole.net.auth.mysql.service.SHA256PasswordEncryptionService;
 import net.sourceforge.guacamole.net.auth.mysql.service.SaltService;
 import net.sourceforge.guacamole.net.auth.mysql.service.SecureRandomSaltService;
 import net.sourceforge.guacamole.net.auth.mysql.service.SystemPermissionService;
+import net.sourceforge.guacamole.net.auth.mysql.service.UnrestrictedGuacamoleSocketService;
 import net.sourceforge.guacamole.net.auth.mysql.service.UserService;
 import org.apache.ibatis.transaction.jdbc.JdbcTransactionFactory;
 import org.glyptodon.guacamole.environment.Environment;
@@ -164,6 +166,9 @@ public class MySQLAuthenticationProvider implements AuthenticationProvider {
                     bind(SystemPermissionService.class);
                     bind(UserService.class);
 
+                    // Bind appropriate socket service based on policy
+                    bind(GuacamoleSocketService.class).to(UnrestrictedGuacamoleSocketService.class);
+                    
                 }
             } // end of mybatis module
 

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/MySQLConnection.java

@@ -28,6 +28,7 @@ import java.util.Collections;
 import java.util.List;
 import net.sourceforge.guacamole.net.auth.mysql.model.ConnectionModel;
 import net.sourceforge.guacamole.net.auth.mysql.service.ConnectionService;
+import net.sourceforge.guacamole.net.auth.mysql.service.GuacamoleSocketService;
 import org.glyptodon.guacamole.GuacamoleException;
 import org.glyptodon.guacamole.net.GuacamoleSocket;
 import org.glyptodon.guacamole.net.auth.Connection;
@@ -59,6 +60,12 @@ public class MySQLConnection implements Connection, DirectoryObject<ConnectionMo
     @Inject
     private ConnectionService connectionService;
 
+    /**
+     * Service for creating and tracking sockets.
+     */
+    @Inject
+    private GuacamoleSocketService socketService;
+
     /**
      * Provider for lazy-loaded, permission-controlled configurations.
      */
@@ -185,8 +192,7 @@ public class MySQLConnection implements Connection, DirectoryObject<ConnectionMo
 
     @Override
     public int getActiveConnections() {
-        /* STUB */
+        return socketService.getActiveConnections(this);
-        return 0;
     }
 
 }

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/service/AbstractGuacamoleSocketService.java

@@ -0,0 +1,238 @@
+/*
+ * 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 net.sourceforge.guacamole.net.auth.mysql.service;
+
+import com.google.inject.Inject;
+import java.util.Collection;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicInteger;
+import net.sourceforge.guacamole.net.auth.mysql.AuthenticatedUser;
+import net.sourceforge.guacamole.net.auth.mysql.MySQLConnection;
+import net.sourceforge.guacamole.net.auth.mysql.dao.ParameterMapper;
+import net.sourceforge.guacamole.net.auth.mysql.model.ConnectionModel;
+import net.sourceforge.guacamole.net.auth.mysql.model.ParameterModel;
+import org.glyptodon.guacamole.GuacamoleException;
+import org.glyptodon.guacamole.environment.Environment;
+import org.glyptodon.guacamole.net.GuacamoleSocket;
+import org.glyptodon.guacamole.net.InetGuacamoleSocket;
+import org.glyptodon.guacamole.net.auth.Connection;
+import org.glyptodon.guacamole.protocol.ConfiguredGuacamoleSocket;
+import org.glyptodon.guacamole.protocol.GuacamoleClientInformation;
+import org.glyptodon.guacamole.protocol.GuacamoleConfiguration;
+
+
+/**
+ * Base implementation of the GuacamoleSocketService, handling retrieval of
+ * connection parameters, load balancing, and connection usage counts. The
+ * implementation of concurrency rules is up to policy-specific subclasses.
+ *
+ * @author Michael Jumper
+ */
+public abstract class AbstractGuacamoleSocketService implements GuacamoleSocketService {
+
+    /**
+     * The environment of the Guacamole server.
+     */
+    @Inject
+    private Environment environment;
+ 
+    /**
+     * Mapper for accessing connection parameters.
+     */
+    @Inject
+    private ParameterMapper parameterMapper;
+
+    /**
+     * The current number of concurrent uses of the connection having a given
+     * identifier.
+     */
+    private final ConcurrentHashMap<String, AtomicInteger> activeConnectionCount =
+            new ConcurrentHashMap<String, AtomicInteger>();
+
+    /**
+     * Atomically increments the current usage count for the given connection.
+     *
+     * @param connection
+     *     The connection which is being used.
+     */
+    private void incrementUsage(MySQLConnection connection) {
+
+        // Increment or initialize usage count atomically
+        AtomicInteger count = activeConnectionCount.putIfAbsent(connection.getIdentifier(), new AtomicInteger(1));
+        if (count != null)
+            count.incrementAndGet();
+
+    }
+
+    /**
+     * Atomically decrements the current usage count for the given connection.
+     * If a combination of incrementUsage() and decrementUsage() calls result
+     * in the usage counter being reduced to zero, it is guaranteed that one
+     * of those decrementUsage() calls will remove the value from the map.
+     *
+     * @param connection
+     *     The connection which is no longer being used.
+     */
+    private void decrementUsage(MySQLConnection connection) {
+
+        // Decrement usage count, remove entry if it becomes zero
+        AtomicInteger count = activeConnectionCount.get(connection.getIdentifier());
+        if (count != null) {
+            count.decrementAndGet();
+            activeConnectionCount.remove(connection.getIdentifier(), 0);
+        }
+
+    }
+
+    /**
+     * Acquires possibly-exclusive access to the given connection on behalf of
+     * the given user. If access is denied for any reason, an exception is
+     * thrown.
+     *
+     * @param user
+     *     The user acquiring access.
+     *
+     * @param connection
+     *     The connection being accessed.
+     *
+     * @throws GuacamoleException
+     *     If access is denied to the given user for any reason.
+     */
+    protected abstract void acquire(AuthenticatedUser user,
+            MySQLConnection connection) throws GuacamoleException;
+
+    /**
+     * Releases possibly-exclusive access to the given connection on behalf of
+     * the given user. If the given user did not already have access, the
+     * behavior of this function is undefined.
+     *
+     * @param user
+     *     The user releasing access.
+     *
+     * @param connection
+     *     The connection being released.
+     */
+    protected abstract void release(AuthenticatedUser user,
+            MySQLConnection connection);
+
+    /**
+     * Creates a socket for the given user which connects to the given
+     * connection. The given client information will be passed to guacd when
+     * the connection is established. This function will apply any concurrent
+     * usage rules in effect, but will NOT test object- or system-level
+     * permissions.
+     *
+     * @param user
+     *     The user for whom the connection is being established.
+     *
+     * @param connection
+     *     The connection the user is connecting to.
+     *
+     * @param info
+     *     Information describing the Guacamole client connecting to the given
+     *     connection.
+     *
+     * @return
+     *     A new GuacamoleSocket which is configured and connected to the given
+     *     connection.
+     *
+     * @throws GuacamoleException
+     *     If the connection cannot be established due to concurrent usage
+     *     rules.
+     */
+    @Override
+    public GuacamoleSocket getGuacamoleSocket(final AuthenticatedUser user,
+            final MySQLConnection connection, GuacamoleClientInformation info)
+            throws GuacamoleException {
+
+        // Generate configuration from available data
+        GuacamoleConfiguration config = new GuacamoleConfiguration();
+
+        // Set protocol from connection
+        ConnectionModel model = connection.getModel();
+        config.setProtocol(model.getProtocol());
+
+        // Set parameters from associated data
+        Collection<ParameterModel> parameters = parameterMapper.select(connection.getIdentifier());
+        for (ParameterModel parameter : parameters)
+            config.setParameter(parameter.getName(), parameter.getValue());
+
+        // Return new socket
+        try {
+
+            // Atomically gain access to connection
+            acquire(user, connection);
+            incrementUsage(connection);
+
+            // Return newly-reserved connection
+            return new ConfiguredGuacamoleSocket(
+                new InetGuacamoleSocket(
+                    environment.getRequiredProperty(Environment.GUACD_HOSTNAME),
+                    environment.getRequiredProperty(Environment.GUACD_PORT)
+                ),
+                config
+            ) {
+
+                @Override
+                public void close() throws GuacamoleException {
+
+                    // Attempt to close connection
+                    super.close();
+                    
+                    // Release connection upon close
+                    decrementUsage(connection);
+                    release(user, connection);
+
+                }
+                
+            };
+
+        }
+
+        // Release connection in case of error
+        catch (GuacamoleException e) {
+
+            // Atomically release access to connection
+            decrementUsage(connection);
+            release(user, connection);
+
+            throw e;
+
+        }
+
+    }
+
+    @Override
+    public int getActiveConnections(Connection connection) {
+
+        // If no such active connection, zero active users
+        AtomicInteger count = activeConnectionCount.get(connection.getIdentifier());
+        if (count == null)
+            return 0;
+
+        // Otherwise, return stored value
+        return count.intValue();
+        
+    }
+    
+}

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/service/ConnectionService.java

@@ -24,8 +24,6 @@ package net.sourceforge.guacamole.net.auth.mysql.service;
 
 import com.google.inject.Inject;
 import com.google.inject.Provider;
-import java.util.Collection;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
@@ -39,17 +37,13 @@ import net.sourceforge.guacamole.net.auth.mysql.model.ParameterModel;
 import org.glyptodon.guacamole.GuacamoleClientException;
 import org.glyptodon.guacamole.GuacamoleException;
 import org.glyptodon.guacamole.GuacamoleSecurityException;
-import org.glyptodon.guacamole.environment.Environment;
 import org.glyptodon.guacamole.net.GuacamoleSocket;
-import org.glyptodon.guacamole.net.InetGuacamoleSocket;
 import org.glyptodon.guacamole.net.auth.Connection;
 import org.glyptodon.guacamole.net.auth.permission.ObjectPermission;
 import org.glyptodon.guacamole.net.auth.permission.ObjectPermissionSet;
 import org.glyptodon.guacamole.net.auth.permission.SystemPermission;
 import org.glyptodon.guacamole.net.auth.permission.SystemPermissionSet;
-import org.glyptodon.guacamole.protocol.ConfiguredGuacamoleSocket;
 import org.glyptodon.guacamole.protocol.GuacamoleClientInformation;
-import org.glyptodon.guacamole.protocol.GuacamoleConfiguration;
 
 /**
  * Service which provides convenience methods for creating, retrieving, and
@@ -59,12 +53,6 @@ import org.glyptodon.guacamole.protocol.GuacamoleConfiguration;
  */
 public class ConnectionService extends DirectoryObjectService<MySQLConnection, Connection, ConnectionModel> {
 
-    /**
-     * The environment of the Guacamole server.
-     */
-    @Inject
-    private Environment environment;
-    
     /**
      * Mapper for accessing connections.
      */
@@ -83,6 +71,12 @@ public class ConnectionService extends DirectoryObjectService<MySQLConnection, C
     @Inject
     private Provider<MySQLConnection> mySQLConnectionProvider;
 
+    /**
+     * Service for creating and tracking sockets.
+     */
+    @Inject
+    private GuacamoleSocketService socketService;
+    
     @Override
     protected DirectoryObjectMapper<ConnectionModel> getObjectMapper() {
         return connectionMapper;
@@ -252,33 +246,9 @@ public class ConnectionService extends DirectoryObjectService<MySQLConnection, C
             MySQLConnection connection, GuacamoleClientInformation info)
             throws GuacamoleException {
 
-        String identifier = connection.getIdentifier();
-        
         // Connect only if READ permission is granted
-        if (hasObjectPermission(user, identifier, ObjectPermission.Type.READ)) {
+        if (hasObjectPermission(user, connection.getIdentifier(), ObjectPermission.Type.READ))
-
+            return socketService.getGuacamoleSocket(user, connection, info);
-            // Generate configuration from available data
-            GuacamoleConfiguration config = new GuacamoleConfiguration();
-
-            // Set protocol from connection
-            ConnectionModel model = connection.getModel();
-            config.setProtocol(model.getProtocol());
-
-            // Set parameters from associated data
-            Collection<ParameterModel> parameters = parameterMapper.select(identifier);
-            for (ParameterModel parameter : parameters)
-                config.setParameter(parameter.getName(), parameter.getValue());
-
-            // Return new socket
-            return new ConfiguredGuacamoleSocket(
-                new InetGuacamoleSocket(
-                    environment.getRequiredProperty(Environment.GUACD_HOSTNAME),
-                    environment.getRequiredProperty(Environment.GUACD_PORT)
-                ),
-                config
-            );
-
-        }
 
         // The user does not have permission to connect
         throw new GuacamoleSecurityException("Permission denied.");

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/service/GuacamoleSocketService.java

@@ -0,0 +1,81 @@
+/*
+ * 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 net.sourceforge.guacamole.net.auth.mysql.service;
+
+import net.sourceforge.guacamole.net.auth.mysql.AuthenticatedUser;
+import net.sourceforge.guacamole.net.auth.mysql.MySQLConnection;
+import org.glyptodon.guacamole.GuacamoleException;
+import org.glyptodon.guacamole.net.GuacamoleSocket;
+import org.glyptodon.guacamole.net.auth.Connection;
+import org.glyptodon.guacamole.protocol.GuacamoleClientInformation;
+
+
+/**
+ * Service which creates pre-configured GuacamoleSocket instances for
+ * connections and balancing groups, applying concurrent usage rules.
+ *
+ * @author Michael Jumper
+ */
+public interface GuacamoleSocketService {
+
+    /**
+     * Creates a socket for the given user which connects to the given
+     * connection. The given client information will be passed to guacd when
+     * the connection is established. This function will apply any concurrent
+     * usage rules in effect, but will NOT test object- or system-level
+     * permissions.
+     *
+     * @param user
+     *     The user for whom the connection is being established.
+     *
+     * @param connection
+     *     The connection the user is connecting to.
+     *
+     * @param info
+     *     Information describing the Guacamole client connecting to the given
+     *     connection.
+     *
+     * @return
+     *     A new GuacamoleSocket which is configured and connected to the given
+     *     connection.
+     *
+     * @throws GuacamoleException
+     *     If the connection cannot be established due to concurrent usage
+     *     rules.
+     */
+    GuacamoleSocket getGuacamoleSocket(AuthenticatedUser user,
+            MySQLConnection connection, GuacamoleClientInformation info)
+            throws GuacamoleException;
+
+    /**
+     * Returns the number of active connections using the given connection.
+     *
+     * @param connection
+     *     The connection to check.
+     *
+     * @return
+     *     The number of active connections using the given connection.
+     */
+    public int getActiveConnections(Connection connection);
+   
+}

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/service/UnrestrictedGuacamoleSocketService.java

@@ -0,0 +1,52 @@
+/*
+ * 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 net.sourceforge.guacamole.net.auth.mysql.service;
+
+import com.google.inject.Singleton;
+import net.sourceforge.guacamole.net.auth.mysql.AuthenticatedUser;
+import net.sourceforge.guacamole.net.auth.mysql.MySQLConnection;
+import org.glyptodon.guacamole.GuacamoleException;
+
+
+/**
+ * GuacamoleSocketService implementation which imposes no restrictions
+ * whatsoever on the number of concurrent or duplicate connections.
+ *
+ * @author Michael Jumper
+ */
+@Singleton
+public class UnrestrictedGuacamoleSocketService
+    extends AbstractGuacamoleSocketService {
+
+    @Override
+    protected void acquire(AuthenticatedUser user, MySQLConnection connection)
+            throws GuacamoleException {
+        // Do nothing
+    }
+
+    @Override
+    protected void release(AuthenticatedUser user, MySQLConnection connection) {
+        // Do nothing
+    }
+
+}