Add TRANSFER_ENCODING violation for MultiPart RFC7578 parser. (#7976)

* Add TRANSFER_ENCODING violation for MultiPart RFC7578 parser.
* Ignore TRANSFER_ENCODING violation for 8bit and binary.

Signed-off-by: Lachlan Roberts <lachlan@webtide.com>

jetty-http/src/main/java/org/eclipse/jetty/http/MultiPartFormInputStream.java

@@ -35,6 +35,7 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.EnumSet;
 import java.util.List;
 import javax.servlet.MultipartConfigElement;
 import javax.servlet.ServletInputStream;
@@ -62,6 +63,7 @@ public class MultiPartFormInputStream
     private static final Logger LOG = Log.getLogger(MultiPartFormInputStream.class);
     private static final MultiMap<Part> EMPTY_MAP = new MultiMap<>(Collections.emptyMap());
     private final MultiMap<Part> _parts;
+    private final EnumSet<NonCompliance> _nonComplianceWarnings = EnumSet.noneOf(NonCompliance.class);
     private InputStream _in;
     private MultipartConfigElement _config;
     private String _contentType;
@@ -72,6 +74,31 @@ public class MultiPartFormInputStream
     private boolean _parsed;
     private int _bufferSize = 16 * 1024;
 
+    public enum NonCompliance
+    {
+        TRANSFER_ENCODING("https://tools.ietf.org/html/rfc7578#section-4.7");
+
+        final String _rfcRef;
+
+        NonCompliance(String rfcRef)
+        {
+            _rfcRef = rfcRef;
+        }
+
+        public String getURL()
+        {
+            return _rfcRef;
+        }
+    }
+
+    /**
+     * @return an EnumSet of non compliances with the RFC that were accepted by this parser
+     */
+    public EnumSet<NonCompliance> getNonComplianceWarnings()
+    {
+        return _nonComplianceWarnings;
+    }
+
     public class MultiPart implements Part
     {
         protected String _name;
@@ -610,7 +637,11 @@ else if (key.equalsIgnoreCase("content-type"))
 
             // Transfer encoding is not longer considers as it is deprecated as per
             // https://tools.ietf.org/html/rfc7578#section-4.7
-
+            if (key.equalsIgnoreCase("content-transfer-encoding"))
+            {
+                if (!"8bit".equalsIgnoreCase(value) && !"binary".equalsIgnoreCase(value))
+                    _nonComplianceWarnings.add(NonCompliance.TRANSFER_ENCODING);
+            }
         }
 
         @Override

jetty-http/src/test/java/org/eclipse/jetty/http/MultiPartFormInputStreamTest.java

@@ -27,13 +27,15 @@
 import java.nio.charset.StandardCharsets;
 import java.util.Base64;
 import java.util.Collection;
+import java.util.EnumSet;
 import java.util.concurrent.atomic.AtomicInteger;
 import javax.servlet.MultipartConfigElement;
 import javax.servlet.ReadListener;
 import javax.servlet.ServletInputStream;
 import javax.servlet.http.Part;
 
 import org.eclipse.jetty.http.MultiPartFormInputStream.MultiPart;
+import org.eclipse.jetty.http.MultiPartFormInputStream.NonCompliance;
 import org.eclipse.jetty.toolchain.test.MavenTestingUtils;
 import org.eclipse.jetty.util.BlockingArrayQueue;
 import org.eclipse.jetty.util.BufferUtil;
@@ -43,6 +45,7 @@
 import static java.nio.charset.StandardCharsets.ISO_8859_1;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.notNullValue;
@@ -887,6 +890,8 @@ public void testBase64EncodedContent() throws Exception
         baos = new ByteArrayOutputStream();
         IO.copy(p3.getInputStream(), baos);
         assertEquals("the end", baos.toString("US-ASCII"));
+
+        assertThat(mpis.getNonComplianceWarnings(), equalTo(EnumSet.of(NonCompliance.TRANSFER_ENCODING)));
     }
 
     @Test
@@ -1016,6 +1021,8 @@ public void testQuotedPrintableEncoding() throws Exception
         baos = new ByteArrayOutputStream();
         IO.copy(p2.getInputStream(), baos);
         assertEquals("truth=3Dbeauty", baos.toString("US-ASCII"));
+
+        assertThat(mpis.getNonComplianceWarnings(), equalTo(EnumSet.of(NonCompliance.TRANSFER_ENCODING)));
     }
 
     @Test

jetty-server/src/main/java/org/eclipse/jetty/server/MultiParts.java

@@ -54,23 +54,29 @@ class MultiPartsHttpParser implements MultiParts
     {
         private final MultiPartFormInputStream _httpParser;
         private final ContextHandler.Context _context;
+        private final Request _request;
 
         public MultiPartsHttpParser(InputStream in, String contentType, MultipartConfigElement config, File contextTmpDir, Request request) throws IOException
         {
             _httpParser = new MultiPartFormInputStream(in, contentType, config, contextTmpDir);
             _context = request.getContext();
+            _request = request;
         }
 
         @Override
         public Collection<Part> getParts() throws IOException
         {
-            return _httpParser.getParts();
+            Collection<Part> parts = _httpParser.getParts();
+            setNonComplianceViolationsOnRequest();
+            return parts;
         }
 
         @Override
         public Part getPart(String name) throws IOException
         {
-            return _httpParser.getPart(name);
+            Part part = _httpParser.getPart(name);
+            setNonComplianceViolationsOnRequest();
+            return part;
         }
 
         @Override
@@ -90,6 +96,22 @@ public Context getContext()
         {
             return _context;
         }
+
+        private void setNonComplianceViolationsOnRequest()
+        {
+            @SuppressWarnings("unchecked")
+            List<String> violations = (List<String>)_request.getAttribute(HttpCompliance.VIOLATIONS_ATTR);
+            if (violations != null)
+                return;
+
+            EnumSet<MultiPartFormInputStream.NonCompliance> nonComplianceWarnings = _httpParser.getNonComplianceWarnings();
+            violations = new ArrayList<>();
+            for (MultiPartFormInputStream.NonCompliance nc : nonComplianceWarnings)
+            {
+                violations.add(nc.name() + ": " + nc.getURL());
+            }
+            _request.setAttribute(HttpCompliance.VIOLATIONS_ATTR, violations);
+        }
     }
 
     @SuppressWarnings("deprecation")