websocket: do not cut the close code bytes from frame's payload

For control CLOSE frame, the frame's length, close code, and payload are
all related.  For example, the length of 2 indicate that there is a close
code in payload.

This change only affect test when unpacking close frame, and does not
affect the result of autobahn test.

3 files changed, 5 insertions, 4 deletions

diff --git a/lib/websocket/frame.go b/lib/websocket/frame.go
index eb52f61c..2bff7335 100644
--- a/lib/websocket/frame.go
+++ b/lib/websocket/frame.go
@@ -317,7 +317,6 @@ func frameUnpack(in []byte) (f *Frame, rest []byte) {
 		default:
 			f.codes = []byte{f.payload[0], f.payload[1]}
 			f.closeCode = CloseCode(binary.BigEndian.Uint16(f.payload[:2]))
-			f.payload = f.payload[2:]
 		}
 	}
 
diff --git a/lib/websocket/frame_test.go b/lib/websocket/frame_test.go
index ea6ae0f8..4cca0beb 100644
--- a/lib/websocket/frame_test.go
+++ b/lib/websocket/frame_test.go
@@ -64,7 +64,7 @@ func TestNewFrameClose(t *testing.T) {
 			opcode:    OpcodeClose,
 			closeCode: StatusBadRequest,
 			masked:    frameIsMasked,
-			payload:   []byte("Hello!"),
+			payload:   libbytes.Concat([]byte{0x03, 0xEA}, []byte("Hello!")),
 		},
 	}, {
 		desc:    "With overflow payload",
@@ -74,7 +74,7 @@ func TestNewFrameClose(t *testing.T) {
 			opcode:    OpcodeClose,
 			closeCode: StatusBadRequest,
 			masked:    frameIsMasked,
-			payload:   _dummyPayload256[:123],
+			payload:   libbytes.Concat([]byte{0x03, 0xEA}, _dummyPayload256[:123]),
 		},
 	}}
 
diff --git a/lib/websocket/server.go b/lib/websocket/server.go
index 4b3715e4..988a24c5 100644
--- a/lib/websocket/server.go
+++ b/lib/websocket/server.go
@@ -609,7 +609,9 @@ func (serv *Server) handleClose(conn int, req *Frame) {
 		// The interpretation of these codes is undefined by this
 		// protocol.
 	}
-	if len(req.payload) > 0 {
+	if len(req.payload) >= 2 {
+		// Cut the close code from actual payload.
+		req.payload = req.payload[2:]
 		if !utf8.Valid(req.payload) {
 			req.closeCode = StatusBadRequest
 		}