GUACAMOLE-1020: Make sure only admin users can modify restrictions.

extensions/guacamole-auth-restrict/src/main/java/org/apache/guacamole/auth/restrict/user/RestrictedUser.java

@@ -43,6 +43,12 @@ public class RestrictedUser extends DelegatingUser implements Restrictable {
      */
     private final String remoteAddress;
 
+    /**
+     * true if the user logged in to Guacamole has administrative privileges
+     * for this user object, otherwise false.
+     */
+    private final boolean hasAdmin;
+
     /**
      * The name of the attribute that contains a list of weekdays and times (UTC)
      * that a user is allowed to log in. The presence of this attribute will
@@ -116,9 +122,10 @@ public class RestrictedUser extends DelegatingUser implements Restrictable {
      *     The remote address of the client from which the current user is logged
      *     in.
      */
-    public RestrictedUser(User user, String remoteAddress) {
+    public RestrictedUser(User user, String remoteAddress, boolean hasAdmin) {
         super(user);
         this.remoteAddress = remoteAddress;
+        this.hasAdmin = hasAdmin;
     }
 
     /**
@@ -133,7 +140,7 @@ public User getUndecorated() {
 
     @Override
     public Map<String, String> getAttributes() {
-
+        
         // Create independent, mutable copy of attributes
         Map<String, String> attributes = new HashMap<>(super.getAttributes());
 
@@ -154,10 +161,18 @@ public void setAttributes(Map<String, String> attributes) {
 
         // Create independent, mutable copy of attributes
         attributes = new HashMap<>(attributes);
-
+        
         // Loop through extension-specific attributes, only sending ones
         // that are non-null and non-empty to the underlying storage mechanism.
         for (String attribute : RESTRICT_USER_ATTRIBUTES) {
+
+            /* If the user lacks admin access, don't set restriction attributes. */
+            if (!hasAdmin) {
+                attributes.remove(attribute);
+                continue;
+            }
+
+            /* Replace empty values with null values. */
             String value = attributes.get(attribute);
             if (value != null && value.isEmpty())
                 attributes.put(attribute, null);

extensions/guacamole-auth-restrict/src/main/java/org/apache/guacamole/auth/restrict/user/RestrictedUserContext.java

@@ -34,9 +34,12 @@
 import org.apache.guacamole.net.auth.DecoratingDirectory;
 import org.apache.guacamole.net.auth.DelegatingUserContext;
 import org.apache.guacamole.net.auth.Directory;
+import org.apache.guacamole.net.auth.Permissions;
 import org.apache.guacamole.net.auth.User;
 import org.apache.guacamole.net.auth.UserContext;
 import org.apache.guacamole.net.auth.UserGroup;
+import org.apache.guacamole.net.auth.permission.ObjectPermission;
+import org.apache.guacamole.net.auth.permission.SystemPermission;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -60,7 +63,7 @@ public class RestrictedUserContext extends DelegatingUserContext {
      * The identifiers effective groups of the user associated with this context.
      */
     private final Set<String> effectiveUserGroups;
-    
+
     /**
      * Creates a new RestrictedUserContext which wraps the given UserContext,
      * providing additional control for user logins and connections.
@@ -133,11 +136,26 @@ public Collection<Form> getConnectionGroupAttributes() {
 
     @Override
     public Directory<User> getUserDirectory() throws GuacamoleException {
+
+        // Pull permissions of the current logged-in user.
+        Permissions currentPermissions = self().getEffectivePermissions();
+
         return new DecoratingDirectory<User>(super.getUserDirectory()) {
 
             @Override
-            protected User decorate(User object) {
-                return new RestrictedUser(object, remoteAddress);
+            protected User decorate(User object) throws GuacamoleException {
+
+                // Check and see if the logged in user has admin privileges -
+                // either system-level or for that particular object.
+                boolean hasAdmin = 
+                        currentPermissions.getSystemPermissions().hasPermission(
+                                        SystemPermission.Type.ADMINISTER
+                        )
+                     || currentPermissions.getUserPermissions().hasPermission(
+                                     ObjectPermission.Type.ADMINISTER,
+                                     object.getIdentifier()
+                        );
+                return new RestrictedUser(object, remoteAddress, hasAdmin);
             }
 
             @Override