Fixing XML parsers security bug

Change-Id: I1fbf2b2bd42669d9a3c059c32bb39278bd483d60
Issue-ID: SO-3668
Signed-off-by: waqas.ikram <waqas.ikram@est.tech>

2 files changed, 24 insertions, 15 deletions

diff --git a/bpmn/MSOCoreBPMN/src/main/java/org/onap/so/bpmn/core/xml/XmlTool.java b/bpmn/MSOCoreBPMN/src/main/java/org/onap/so/bpmn/core/xml/XmlTool.java
index 58238c8ff6..79a4c54e23 100644
--- a/bpmn/MSOCoreBPMN/src/main/java/org/onap/so/bpmn/core/xml/XmlTool.java
+++ b/bpmn/MSOCoreBPMN/src/main/java/org/onap/so/bpmn/core/xml/XmlTool.java
@@ -224,7 +224,7 @@ public final class XmlTool {
      * @return the contents of the modified XML document as a String or null/empty if the modification failed.
      * @throws IOException, TransformerException, ParserConfigurationException, SAXException
      */
-    public static Optional<String> modifyElement(String xml, String elementTag, String newValue)
+    public static Optional<String> modifyElement(final String xml, final String elementTag, final String newValue)
             throws IOException, TransformerException, ParserConfigurationException, SAXException {
 
         if (xml == null || xml.isEmpty()) {
@@ -232,15 +232,15 @@ public final class XmlTool {
             return Optional.empty();
         }
 
-        DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
+        final DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
         dbFactory.setNamespaceAware(true);
         dbFactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
         dbFactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
-        DocumentBuilder db = dbFactory.newDocumentBuilder();
-        InputSource source = new InputSource(new StringReader(xml));
-        Document doc = db.parse(source);
+        final DocumentBuilder db = dbFactory.newDocumentBuilder();
+        final InputSource source = new InputSource(new StringReader(xml));
+        final Document doc = db.parse(source);
 
-        Node modNode = doc.getElementsByTagName(elementTag).item(0);
+        final Node modNode = doc.getElementsByTagName(elementTag).item(0);
         if (modNode == null) {
             // did not find the specified element to be modified, return empty
             // System.out.println("Did not find element tag " + elementTag + " in XML");
@@ -249,9 +249,12 @@ public final class XmlTool {
             modNode.setTextContent(newValue);
         }
 
-        TransformerFactory transformerFactory = TransformerFactory.newInstance();
-        Transformer transformer = transformerFactory.newTransformer();
-        StringWriter writer = new StringWriter();
+        final TransformerFactory transformerFactory = TransformerFactory.newInstance();
+        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, StringUtils.EMPTY);
+        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, StringUtils.EMPTY);
+
+        final Transformer transformer = transformerFactory.newTransformer();
+        final StringWriter writer = new StringWriter();
         transformer.transform(new DOMSource(doc), new StreamResult(writer));
         // return the modified String representation of the XML
         return Optional.of(writer.toString().trim());
diff --git a/bpmn/so-bpmn-tasks/src/main/java/org/onap/so/bpmn/infrastructure/adapter/network/tasks/NetworkAdapterImpl.java b/bpmn/so-bpmn-tasks/src/main/java/org/onap/so/bpmn/infrastructure/adapter/network/tasks/NetworkAdapterImpl.java
index 8e6e8678ed..7c6473f79d 100644
--- a/bpmn/so-bpmn-tasks/src/main/java/org/onap/so/bpmn/infrastructure/adapter/network/tasks/NetworkAdapterImpl.java
+++ b/bpmn/so-bpmn-tasks/src/main/java/org/onap/so/bpmn/infrastructure/adapter/network/tasks/NetworkAdapterImpl.java
@@ -2,12 +2,15 @@ package org.onap.so.bpmn.infrastructure.adapter.network.tasks;
 
 import java.io.ByteArrayInputStream;
 import java.io.StringReader;
+import java.nio.charset.StandardCharsets;
 import java.util.Optional;
+import javax.xml.XMLConstants;
 import javax.xml.bind.JAXBContext;
 import javax.xml.bind.JAXBException;
 import javax.xml.bind.Unmarshaller;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
+import org.apache.commons.lang3.StringUtils;
 import org.onap.so.adapters.nwrest.CreateNetworkResponse;
 import org.onap.so.adapters.nwrest.DeleteNetworkResponse;
 import org.onap.so.adapters.nwrest.UpdateNetworkResponse;
@@ -22,6 +25,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
+import org.w3c.dom.Document;
 
 @Component
 public class NetworkAdapterImpl {
@@ -80,14 +84,16 @@ public class NetworkAdapterImpl {
         return unmarshaller.unmarshal(reader);
     }
 
-    protected Optional<String> findResponseType(String xmlString) {
+    protected Optional<String> findResponseType(final String xmlString) {
         try {
-            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
-            DocumentBuilder builder = factory.newDocumentBuilder();
-            org.w3c.dom.Document doc;
-            doc = builder.parse(new ByteArrayInputStream(xmlString.getBytes("UTF-8")));
+            final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+            factory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, StringUtils.EMPTY);
+            factory.setAttribute(XMLConstants.ACCESS_EXTERNAL_SCHEMA, StringUtils.EMPTY);
+
+            final DocumentBuilder builder = factory.newDocumentBuilder();
+            final Document doc = builder.parse(new ByteArrayInputStream(xmlString.getBytes(StandardCharsets.UTF_8)));
             return Optional.of(doc.getDocumentElement().getNodeName());
-        } catch (Exception e) {
+        } catch (final Exception e) {
             logger.error("Error Finding Response Type", e);
             return Optional.empty();
         }