From bd67f537c9b8ae200e0b9ffc5eaac0b3fb60c7c2 Mon Sep 17 00:00:00 2001
From: Lucas Clemente <lucas@clemente.io>
Date: Wed, 27 Apr 2016 13:02:00 +0200
Subject: [PATCH] add support for receiving BLOCKED frames

---
 frames/blocked_frame.go      | 42 ++++++++++++++++++++++++++++++++++++
 frames/blocked_frame_test.go | 20 +++++++++++++++++
 packet_unpacker.go           |  5 +----
 packet_unpacker_test.go      |  8 +++++--
 session.go                   |  5 +++++
 5 files changed, 74 insertions(+), 6 deletions(-)
 create mode 100644 frames/blocked_frame.go
 create mode 100644 frames/blocked_frame_test.go

diff --git a/frames/blocked_frame.go b/frames/blocked_frame.go
new file mode 100644
index 000000000..a1a61a8c4
--- /dev/null
+++ b/frames/blocked_frame.go
@@ -0,0 +1,42 @@
+package frames
+
+import (
+	"bytes"
+
+	"github.com/lucas-clemente/quic-go/protocol"
+	"github.com/lucas-clemente/quic-go/utils"
+)
+
+// A BlockedFrame in QUIC
+type BlockedFrame struct {
+	StreamID protocol.StreamID
+}
+
+//Write writes a RST_STREAM frame
+func (f *BlockedFrame) Write(b *bytes.Buffer, packetNumber protocol.PacketNumber, packetNumberLen uint8) error {
+	panic("BlockedFrame: Write not yet implemented")
+}
+
+// MinLength of a written frame
+func (f *BlockedFrame) MinLength() int {
+	panic("BlockedFrame: Write not yet implemented")
+}
+
+// ParseBlockedFrame parses a BLOCKED frame
+func ParseBlockedFrame(r *bytes.Reader) (*BlockedFrame, error) {
+	frame := &BlockedFrame{}
+
+	// read the TypeByte
+	_, err := r.ReadByte()
+	if err != nil {
+		return nil, err
+	}
+
+	sid, err := utils.ReadUint32(r)
+	if err != nil {
+		return nil, err
+	}
+	frame.StreamID = protocol.StreamID(sid)
+
+	return frame, nil
+}
diff --git a/frames/blocked_frame_test.go b/frames/blocked_frame_test.go
new file mode 100644
index 000000000..b068cc8a4
--- /dev/null
+++ b/frames/blocked_frame_test.go
@@ -0,0 +1,20 @@
+package frames
+
+import (
+	"bytes"
+
+	"github.com/lucas-clemente/quic-go/protocol"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("BlockedFrame", func() {
+	Context("when parsing", func() {
+		It("accepts sample frame", func() {
+			b := bytes.NewReader([]byte{0x05, 0xEF, 0xBE, 0xAD, 0xDE})
+			frame, err := ParseBlockedFrame(b)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(frame.StreamID).To(Equal(protocol.StreamID(0xDEADBEEF)))
+		})
+	})
+})
diff --git a/packet_unpacker.go b/packet_unpacker.go
index a5d583011..d51d2829d 100644
--- a/packet_unpacker.go
+++ b/packet_unpacker.go
@@ -63,10 +63,7 @@ ReadLoop:
 			case 0x04:
 				frame, err = frames.ParseWindowUpdateFrame(r)
 			case 0x05:
-				fmt.Println("unimplemented: BLOCKED")
-				p := make([]byte, 1+4)
-				_, err = r.Read(p)
-				frame = nil
+				frame, err = frames.ParseBlockedFrame(r)
 			case 0x06:
 				frame, err = frames.ParseStopWaitingFrame(r, publicHeader.PacketNumber, publicHeader.PacketNumberLen)
 			case 0x07:
diff --git a/packet_unpacker_test.go b/packet_unpacker_test.go
index a11bb6419..3761af7e0 100644
--- a/packet_unpacker_test.go
+++ b/packet_unpacker_test.go
@@ -138,10 +138,14 @@ var _ = Describe("Packet unpacker", func() {
 	})
 
 	It("accepts BLOCKED frames", func() {
-		setReader([]byte{0x05, 0, 0, 0, 0})
+		setReader([]byte{0x05, 0xEF, 0xBE, 0xAD, 0xDE})
 		packet, err := unpacker.Unpack(hdrBin, hdr, r)
 		Expect(err).ToNot(HaveOccurred())
-		Expect(packet.frames).To(HaveLen(0))
+		Expect(packet.frames).To(Equal([]frames.Frame{
+			&frames.BlockedFrame{
+				StreamID: 0xDEADBEEF,
+			},
+		}))
 	})
 
 	It("unpacks STOP_WAITING frames", func() {
diff --git a/session.go b/session.go
index b42968730..ea30aa3d2 100644
--- a/session.go
+++ b/session.go
@@ -30,6 +30,8 @@ type StreamCallback func(*Session, utils.Stream)
 
 // A Session is a QUIC session
 type Session struct {
+	connectionID protocol.ConnectionID
+
 	streamCallback StreamCallback
 
 	conn connection
@@ -54,6 +56,7 @@ type Session struct {
 // NewSession makes a new session
 func NewSession(conn connection, v protocol.VersionNumber, connectionID protocol.ConnectionID, sCfg *handshake.ServerConfig, streamCallback StreamCallback) PacketHandler {
 	session := &Session{
+		connectionID:          connectionID,
 		conn:                  conn,
 		streamCallback:        streamCallback,
 		streams:               make(map[protocol.StreamID]*stream),
@@ -146,6 +149,8 @@ func (s *Session) handlePacket(remoteAddr interface{}, publicHeader *PublicHeade
 			err = s.handleRstStreamFrame(frame)
 		case *frames.WindowUpdateFrame:
 			fmt.Printf("%#v\n", frame)
+		case *frames.BlockedFrame:
+			fmt.Printf("BLOCKED frame received for connection %d stream %d\n", s.connectionID, frame.StreamID)
 		default:
 			panic("unexpected frame type")
 		}