GUACAMOLE-1723: Merge automatic enforcement of access time restrictions for logged in users.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/JDBCEnvironment.java

@@ -227,4 +227,18 @@ public abstract class JDBCEnvironment extends DelegatingEnvironment {
      */
     public abstract boolean trackExternalConnectionHistory() throws GuacamoleException;
 
+    /**
+     * Returns a boolean value representing whether access time windows should
+     * be enforced for active connections - i.e. whether a currently-connected
+     * user should be disconnected upon the closure of an access window.
+     *
+     * @return
+     *     true if a connected user should be disconnected upon an access time
+     *     window closing, false otherwise.
+     *
+     * @throws GuacamoleException
+     *     If guacamole.properties cannot be parsed.
+     */
+    public abstract boolean enforceAccessWindowsForActiveSessions() throws GuacamoleException;
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/user/ModeledUserContext.java

@@ -29,6 +29,7 @@ import java.util.Collection;
 import java.util.Date;
 import org.apache.guacamole.GuacamoleException;
 import org.apache.guacamole.auth.jdbc.base.RestrictedObject;
+import org.apache.guacamole.auth.jdbc.JDBCEnvironment;
 import org.apache.guacamole.auth.jdbc.activeconnection.ActiveConnectionDirectory;
 import org.apache.guacamole.auth.jdbc.base.ActivityRecordModel;
 import org.apache.guacamole.auth.jdbc.connection.ConnectionRecordSet;
@@ -50,6 +51,8 @@ import org.apache.guacamole.net.auth.SharingProfile;
 import org.apache.guacamole.net.auth.User;
 import org.apache.guacamole.net.auth.UserContext;
 import org.apache.guacamole.net.auth.UserGroup;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * UserContext implementation which is driven by an arbitrary, underlying
@@ -58,6 +61,11 @@ import org.apache.guacamole.net.auth.UserGroup;
 public class ModeledUserContext extends RestrictedObject
     implements org.apache.guacamole.net.auth.UserContext {
 
+    /**
+     * Logger for this class.
+     */
+    private static final Logger logger = LoggerFactory.getLogger(ModeledUserContext.class);
+
     /**
      * User directory restricted by the permissions of the user associated
      * with this context.
@@ -130,6 +138,12 @@ public class ModeledUserContext extends RestrictedObject
     @Inject
     private UserRecordMapper userRecordMapper;
 
+    /**
+     * The environment of the Guacamole server.
+     */
+    @Inject
+    private JDBCEnvironment environment;
+
     /**
      * The activity record associated with this user's Guacamole session. If
      * this user's session will not have an associated activity record, such as
@@ -296,4 +310,31 @@ public class ModeledUserContext extends RestrictedObject
 
     }
 
+    @Override
+    public boolean isValid() {
+
+        try {
+            // If access window enforcement is disabled for active sessions,
+            // skip validity checks entirely
+            if (!environment.enforceAccessWindowsForActiveSessions())
+                return true;
+        }
+
+        catch (GuacamoleException e) {
+
+            logger.warn(
+                    "Unable to determine if access window enforcement is"
+                    + " enabled for active sessions; enforcing by default: {}"
+                    , e.getMessage());
+            logger.debug("Unable to determine access window enforcement policy.", e);
+
+        }
+
+        // A user context is valid if the associated user's account is valid
+        // for the current date, and the user is within an access time window
+        ModeledUser user = getCurrentUser().getUser();
+        return user.isAccountValid() && user.isAccountAccessible();
+
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-mysql/src/main/java/org/apache/guacamole/auth/mysql/conf/MySQLEnvironment.java

@@ -412,4 +412,13 @@ public class MySQLEnvironment extends JDBCEnvironment {
                 true);
     }
 
+    @Override
+    public boolean enforceAccessWindowsForActiveSessions() throws GuacamoleException {
+
+        // Enforce access window restrictions for active sessions unless explicitly disabled
+        return getProperty(
+                MySQLGuacamoleProperties.MYSQL_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS,
+                true);
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-mysql/src/main/java/org/apache/guacamole/auth/mysql/conf/MySQLGuacamoleProperties.java

@@ -278,4 +278,17 @@ public class MySQLGuacamoleProperties {
 
     };
 
+    /**
+     * Whether or not user-specific access time windows should be enforced for active sessions,
+     * i.e. whether users with active sessions should be logged out immediately when an access
+     * window closes.
+     */
+    public static final BooleanGuacamoleProperty MYSQL_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS =
+            new BooleanGuacamoleProperty() {
+
+        @Override
+        public String getName() { return "mysql-enforce-access-windows-for-active-sessions"; }
+
+    };
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java

@@ -371,4 +371,13 @@ public class PostgreSQLEnvironment extends JDBCEnvironment {
                 true);
     }
 
+    @Override
+    public boolean enforceAccessWindowsForActiveSessions() throws GuacamoleException {
+
+        // Enforce access window restrictions for active sessions unless explicitly disabled
+        return getProperty(
+                PostgreSQLGuacamoleProperties.POSTGRESQL_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS,
+                true);
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLGuacamoleProperties.java

@@ -290,4 +290,17 @@ public class PostgreSQLGuacamoleProperties {
 
     };
 
+    /**
+     * Whether or not user-specific access time windows should be enforced for active sessions,
+     * i.e. whether users with active sessions should be logged out immediately when an access
+     * window closes.
+     */
+    public static final BooleanGuacamoleProperty POSTGRESQL_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS =
+            new BooleanGuacamoleProperty() {
+
+        @Override
+        public String getName() { return "postgresql-enforce-access-windows-for-active-sessions"; }
+
+    };
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/conf/SQLServerEnvironment.java

@@ -268,4 +268,13 @@ public class SQLServerEnvironment extends JDBCEnvironment {
                 true);
     }
 
+    @Override
+    public boolean enforceAccessWindowsForActiveSessions() throws GuacamoleException {
+
+        // Enforce access window restrictions for active sessions unless explicitly disabled
+        return getProperty(
+                SQLServerGuacamoleProperties.SQLSERVER_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS,
+                true);
+    }
+
 }

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/conf/SQLServerGuacamoleProperties.java

@@ -220,4 +220,17 @@ public class SQLServerGuacamoleProperties {
 
     };
 
+    /**
+     * Whether or not user-specific access time windows should be enforced for active sessions,
+     * i.e. whether users with active sessions should be logged out immediately when an access
+     * window closes.
+     */
+    public static final BooleanGuacamoleProperty SQLSERVER_ENFORCE_ACCESS_WINDOWS_FOR_ACTIVE_SESSIONS =
+            new BooleanGuacamoleProperty() {
+
+        @Override
+        public String getName() { return "sqlserver-enforce-access-windows-for-active-sessions"; }
+
+    };
+
 }

guacamole-ext/src/main/java/org/apache/guacamole/net/auth/DelegatingUserContext.java

@@ -162,4 +162,9 @@ public class DelegatingUserContext implements UserContext {
         return userContext.getPrivileged();
     }
 
+    @Override
+    public boolean isValid() {
+        return userContext.isValid();
+    }
+
 }

guacamole-ext/src/main/java/org/apache/guacamole/net/auth/UserContext.java

@@ -40,6 +40,27 @@ public interface UserContext {
      */
     User self();
 
+    /**
+     * Returns true if the session for the User associated with this user
+     * context is valid, or false otherwise. If the session is not valid,
+     * the webapp can be expected to terminate the session within a short
+     * period of time.
+     *
+     * NOTE: The webapp currently checks once a minute, and terminates any
+     * session marked as invalid.
+     *
+     * @return
+     *     true if the session for the User associated with this user
+     *     context is valid, or false otherwise.
+     */
+    default boolean isValid() {
+
+        // A user context is always valid unless explicitly updated by an
+        // implementation
+        return true;
+
+    }
+
     /**
      * Returns an arbitrary REST resource representing this UserContext. The
      * REST resource returned must be properly annotated with JSR-311

guacamole/src/main/java/org/apache/guacamole/GuacamoleSession.java

@@ -132,6 +132,22 @@ public class GuacamoleSession {
         return Collections.unmodifiableList(userContexts);
     }
 
+    /**
+     * Returns true if all user contexts associated with this session are
+     * valid, or false if any user context is not valid. If a session is not
+     * valid, it may no longer be used, and invalidate() should be invoked.
+     *
+     * @return
+     *     true if all user contexts associated with this session are
+     *     valid, or false if any user context is not valid.
+     */
+    public boolean isValid() {
+
+        // Immediately return false if any user context is not valid
+        return !userContexts.stream().anyMatch(
+                userContext -> !userContext.isValid());
+    }
+
     /**
      * Returns the UserContext associated with this session that originated
      * from the AuthenticationProvider with the given identifier. If no such

guacamole/src/main/java/org/apache/guacamole/rest/auth/HashTokenSessionMap.java

@@ -94,7 +94,8 @@ public class HashTokenSessionMap implements TokenSessionMap {
 
     /**
      * Task which iterates through all active sessions, evicting those sessions
-     * which are beyond the session timeout.
+     * which are beyond the session timeout, or are marked as invalid by an
+     * extension.
      */
     private class SessionEvictionTask implements Runnable {
 
@@ -105,7 +106,8 @@ public class HashTokenSessionMap implements TokenSessionMap {
 
         /**
          * Creates a new task which automatically evicts sessions which are
-         * older than the specified timeout.
+         * older than the specified timeout, or are marked as invalid by an
+         * extension.
          * 
          * @param sessionTimeout The maximum age of any session, in
          *                       milliseconds.
@@ -116,16 +118,16 @@ public class HashTokenSessionMap implements TokenSessionMap {
 
         /**
          * Iterates through all active sessions, evicting those sessions which
-         * are beyond the session timeout. Internal errors which would
+         * are beyond the session timeout, or are marked as invalid. Internal
-         * otherwise stop the session eviction process are caught, logged, and
+         * errors which would otherwise stop the session eviction process are
-         * the process is allowed to proceed.
+         * caught, logged, and the process is allowed to proceed.
          */
-        private void evictExpiredSessions() {
+        private void evictExpiredOrInvalidSessions() {
 
             // Get start time of session check time
             long sessionCheckStart = System.currentTimeMillis();
 
-            logger.debug("Checking for expired sessions...");
+            logger.debug("Checking for expired or invalid sessions...");
 
             // For each session, remove sesions which have expired
             Iterator<Map.Entry<String, GuacamoleSession>> entries = sessionMap.entrySet().iterator();
@@ -136,6 +138,15 @@ public class HashTokenSessionMap implements TokenSessionMap {
 
                 try {
 
+                    // Invalidate any sessions which have been flagged as invalid by extensions
+                    if (!session.isValid()) {
+                        logger.debug(
+                                "Session \"{}\" has been invalidated by an extension.",
+                                entry.getKey());
+                        entries.remove();
+                        session.invalidate();
+                    }
+
                     // Do not expire sessions which are active
                     if (session.hasTunnels())
                         continue;
@@ -170,13 +181,13 @@ public class HashTokenSessionMap implements TokenSessionMap {
         @Override
         public void run() {
 
-            // The evictExpiredSessions() function should already
+            // The evictExpiredOrInvalidSessions() function should already
             // automatically handle and log all unexpected internal errors,
             // but wrap the entire call in a try/catch plus additional logging
             // to ensure that absolutely no errors can result in the entire
             // thread dying
             try {
-                evictExpiredSessions();
+                evictExpiredOrInvalidSessions();
             }
             catch (Throwable t) {
                 logger.error("An unexpected internal error prevented the "