diff --git a/repos/os/run/rom_filter.run b/repos/os/run/rom_filter.run
index 2d25e48879..a8b2d5cbef 100644
--- a/repos/os/run/rom_filter.run
+++ b/repos/os/run/rom_filter.run
@@ -53,7 +53,12 @@ append config {
 				</inline>
 				<sleep milliseconds="1000" />
 				<inline description="leave X-ray mode undefined">
-					<xray/> <!-- undefined -->
+					<xray> <!-- undefined -->
+						<details>
+							<message reason="error"/> <!-- not selected -->
+							<message reason="no access" text="system locked"/>
+						</details>
+					</xray>
 				</inline>
 				<sleep milliseconds="1000" />
 				<inline description="finished"/>
@@ -70,22 +75,23 @@ append config {
 				<attribute name="enabled" />
 			</input>
 
+			<input name="diagnostic_message" rom="xray" node="xray">
+				<node type="details">
+					<node type="message" attribute="reason" value="no access">
+						<attribute name="text" />
+					</node>
+				</node>
+			</input>
+
 			<output node="config">
+				<attribute name="message" input="diagnostic_message"/>
 				<if>
-					<has_value input="xray_enabled" value="no" />
+					<has_value input="xray_enabled" value="yes" />
 					<then>
-						<inline><!-- .. flat window decorations ... --></inline>
+						<inline><!-- xray enabled --></inline>
 					</then>
 					<else>
-						<if>
-							<has_value input="xray_enabled" value="yes" />
-							<then>
-								<inline><!-- ... colored window decorations ... --></inline>
-							</then>
-							<else>
-								<inline><!-- ... fallback ... --></inline>
-							</else>
-						</if>
+						<inline><!-- ... fallback ... --></inline>
 					</else>
 				</if>
 			</output>
@@ -130,10 +136,10 @@ compare_output_to {
 [init -> rom_logger] ROM 'generated':
 [init -> rom_logger]   <config><!-- ... fallback ... --></config>
 [init -> rom_logger] ROM 'generated':
-[init -> rom_logger]   <config><!-- .. flat window decorations ... --></config>
-[init -> rom_logger] ROM 'generated':
-[init -> rom_logger]   <config><!-- ... colored window decorations ... --></config>
-[init -> rom_logger] ROM 'generated':
 [init -> rom_logger]   <config><!-- ... fallback ... --></config>
+[init -> rom_logger] ROM 'generated':
+[init -> rom_logger]   <config><!-- xray enabled --></config>
+[init -> rom_logger] ROM 'generated':
+[init -> rom_logger]   <config message="system locked"><!-- ... fallback ... --></config>
 }
 
diff --git a/repos/os/src/server/rom_filter/README b/repos/os/src/server/rom_filter/README
index 07fbe10aa3..db4d559657 100644
--- a/repos/os/src/server/rom_filter/README
+++ b/repos/os/src/server/rom_filter/README
@@ -10,12 +10,17 @@ Configuration
 
 The configuration consists of two parts. The first part is the declaration of
 input values that are taken into the account. The input values are obtained
-from ROM modules that contain XML-formatted data. Each input value is
-represented by an '<input>' node with a unique 'name' attribute. The 'rom'
-attribute specifies the ROM module to take the input from. If not specified,
-the 'name' is used as the ROM name. The type of the top-level XML node can be
-specified via the 'node' attribute. If not present, the top-level XML node is
-expected to correspond to the 'name' attribute.
+from ROM modules that contain XML-formatted data.
+
+Each input value is represented by an '<input>' node with a unique 'name'
+attribute. The 'rom' attribute specifies the ROM module to take the input
+from. If not specified, the 'name' is used as the ROM name. The type of the
+top-level XML node can be specified via the 'node' attribute. If not present,
+the top-level XML node is expected to correspond to the 'name' attribute.
+The '<input>' node may contain a hierarchy of '<node type="type">' nodes that
+denote a path within the XML input. If specified, the optional attributes
+'attribute' and 'value' constrain the selection of the input depending of the
+presence and the value of the specified attribute.
 
 The second part of the configuration defines the output via an '<output>' node.
 The type of the top-level XML node must be specified via the 'node' attribute.
diff --git a/repos/os/src/server/rom_filter/input_rom_registry.h b/repos/os/src/server/rom_filter/input_rom_registry.h
index a3c89832f3..43eb0cc1d9 100644
--- a/repos/os/src/server/rom_filter/input_rom_registry.h
+++ b/repos/os/src/server/rom_filter/input_rom_registry.h
@@ -88,6 +88,47 @@ class Rom_filter::Input_rom_registry
 				Genode::Signal_handler<Entry> _rom_changed_handler =
 					{ _env.ep(), *this, &Entry::_handle_rom_changed };
 
+				/**
+				 * Return sub node of 'content' according to the constraints
+				 * given by 'path'
+				 *
+				 * \throw Xml_node::Nonexistent_sub_node
+				 */
+				static Xml_node _matching_sub_node(Node_type_name type,
+				                                   Xml_node const &path,
+				                                   Xml_node const &content)
+				{
+					typedef Input_value Attribute_value;
+
+					Xml_node sub_node = content.sub_node(type.string());
+
+					Attribute_name const expected_attr =
+						path.attribute_value("attribute", Attribute_name());
+
+					Attribute_value const expected_value =
+						path.attribute_value("value", Attribute_value());
+
+					for (;; sub_node = sub_node.next(type.string())) {
+
+						/* attribute remains unspecified -> match */
+						if (!expected_attr.valid())
+							return sub_node;
+
+						/* value remains unspecified -> match */
+						if (!expected_value.valid())
+							return sub_node;
+
+						Attribute_value const present_value =
+							sub_node.attribute_value(expected_attr.string(),
+							                         Attribute_value());
+
+						if (present_value == expected_value)
+							return sub_node;
+					}
+
+					throw Xml_node::Nonexistent_sub_node();
+				}
+
 				/**
 				 * Query value from XML-structured ROM content
 				 *
@@ -122,8 +163,12 @@ class Rom_filter::Input_rom_registry
 							Node_type_name const sub_node_type =
 								path.attribute_value("type", Node_type_name(""));
 
-							content = content.sub_node(sub_node_type.string());
-							path    = path.sub_node();
+							try {
+								content = _matching_sub_node(sub_node_type, path, content);
+								path    = path.sub_node();
+							}
+							catch (Xml_node::Nonexistent_sub_node) {
+								throw Nonexistent_input_value(); }
 
 							continue;
 						}