From d0897fa0b347ce9214dede60e16636e364b6e535 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Tue, 22 May 2018 13:46:44 +0800
Subject: [PATCH] ignore HTTP2 PRIORITY frames in the server

---
 h2quic/server.go      | 12 ++++++++++--
 h2quic/server_test.go | 18 ++++++++++++++++++
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/h2quic/server.go b/h2quic/server.go
index 857211d2e..0f3ad6dc2 100644
--- a/h2quic/server.go
+++ b/h2quic/server.go
@@ -154,10 +154,18 @@ func (s *Server) handleRequest(session streamCreator, headerStream quic.Stream,
 	if err != nil {
 		return qerr.Error(qerr.HeadersStreamDataDecompressFailure, "cannot read frame")
 	}
-	h2headersFrame, ok := h2frame.(*http2.HeadersFrame)
-	if !ok {
+	var h2headersFrame *http2.HeadersFrame
+	switch f := h2frame.(type) {
+	case *http2.PriorityFrame:
+		// ignore PRIORITY frames
+		s.logger.Debugf("Ignoring H2 PRIORITY frame: %#v", f)
+		return nil
+	case *http2.HeadersFrame:
+		h2headersFrame = f
+	default:
 		return qerr.Error(qerr.InvalidHeadersStreamData, "expected a header frame")
 	}
+
 	if !h2headersFrame.HeadersEnded() {
 		return errors.New("http2 header continuation not implemented")
 	}
diff --git a/h2quic/server_test.go b/h2quic/server_test.go
index 5217a7253..28597594e 100644
--- a/h2quic/server_test.go
+++ b/h2quic/server_test.go
@@ -259,6 +259,24 @@ var _ = Describe("H2 server", func() {
 			Expect(dataStream.reset).To(BeFalse())
 		})
 
+		It("ignores PRIORITY frames", func() {
+			handlerCalled := make(chan struct{})
+			s.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				close(handlerCalled)
+			})
+			buf := &bytes.Buffer{}
+			framer := http2.NewFramer(buf, nil)
+			err := framer.WritePriority(10, http2.PriorityParam{Weight: 42})
+			Expect(err).ToNot(HaveOccurred())
+			Expect(buf.Bytes()).ToNot(BeEmpty())
+			headerStream.dataToRead.Write(buf.Bytes())
+			err = s.handleRequest(session, headerStream, &sync.Mutex{}, hpackDecoder, h2framer)
+			Expect(err).ToNot(HaveOccurred())
+			Consistently(handlerCalled).ShouldNot(BeClosed())
+			Expect(dataStream.reset).To(BeFalse())
+			Expect(dataStream.closed).To(BeFalse())
+		})
+
 		It("errors when non-header frames are received", func() {
 			headerStream.dataToRead.Write([]byte{
 				0x0, 0x0, 0x06, 0x0, 0x0, 0x0, 0x0, 0x0, 0x5,