http/spdy: new package

R=bradfitz, agl1, rsc
CC=golang-dev
https://golang.org/cl/4435055

src/pkg/Makefile

@@ -103,6 +103,7 @@ DIRS=\
 	http/fcgi\
 	http/pprof\
 	http/httptest\
+	http/spdy\
 	image\
 	image/jpeg\
 	image/png\

src/pkg/http/spdy/Makefile

+# Copyright 2011 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+include ../../../Make.inc
+
+TARG=http/spdy
+GOFILES=\
+	protocol.go\
+
+include ../../../Make.pkg

src/pkg/http/spdy/protocol.go

+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package spdy is an incomplete implementation of the SPDY protocol.
+//
+// The implementation follows draft 2 of the spec:
+// https://sites.google.com/a/chromium.org/dev/spdy/spdy-protocol/spdy-protocol-draft2
+package spdy
+
+import (
+	"bytes"
+	"compress/zlib"
+	"encoding/binary"
+	"http"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+// Version is the protocol version number that this package implements.
+const Version = 2
+
+// ControlFrameType stores the type field in a control frame header.
+type ControlFrameType uint16
+
+// Control frame type constants
+const (
+	TypeSynStream    ControlFrameType = 0x0001
+	TypeSynReply     = 0x0002
+	TypeRstStream    = 0x0003
+	TypeSettings     = 0x0004
+	TypeNoop         = 0x0005
+	TypePing         = 0x0006
+	TypeGoaway       = 0x0007
+	TypeHeaders      = 0x0008
+	TypeWindowUpdate = 0x0009
+)
+
+func (t ControlFrameType) String() string {
+	switch t {
+	case TypeSynStream:
+		return "SYN_STREAM"
+	case TypeSynReply:
+		return "SYN_REPLY"
+	case TypeRstStream:
+		return "RST_STREAM"
+	case TypeSettings:
+		return "SETTINGS"
+	case TypeNoop:
+		return "NOOP"
+	case TypePing:
+		return "PING"
+	case TypeGoaway:
+		return "GOAWAY"
+	case TypeHeaders:
+		return "HEADERS"
+	case TypeWindowUpdate:
+		return "WINDOW_UPDATE"
+	}
+	return "Type(" + strconv.Itoa(int(t)) + ")"
+}
+
+type FrameFlags uint8
+
+// Stream frame flags
+const (
+	FlagFin            FrameFlags = 0x01
+	FlagUnidirectional = 0x02
+)
+
+// SETTINGS frame flags
+const (
+	FlagClearPreviouslyPersistedSettings = 0x01
+)
+
+// MaxDataLength is the maximum number of bytes that can be stored in one frame.
+const MaxDataLength = 1<<24 - 1
+
+// A Frame is a framed message as sent between clients and servers.
+// There are two types of frames: control frames and data frames.
+type Frame struct {
+	Header [4]byte
+	Flags  FrameFlags
+	Data   []byte
+}
+
+// ControlFrame creates a control frame with the given information.
+func ControlFrame(t ControlFrameType, f FrameFlags, data []byte) Frame {
+	return Frame{
+		Header: [4]byte{
+			(Version&0xff00)>>8 | 0x80,
+			(Version & 0x00ff),
+			byte((t & 0xff00) >> 8),
+			byte((t & 0x00ff) >> 0),
+		},
+		Flags: f,
+		Data:  data,
+	}
+}
+
+// DataFrame creates a data frame with the given information.
+func DataFrame(streamId uint32, f FrameFlags, data []byte) Frame {
+	return Frame{
+		Header: [4]byte{
+			byte(streamId & 0x7f000000 >> 24),
+			byte(streamId & 0x00ff0000 >> 16),
+			byte(streamId & 0x0000ff00 >> 8),
+			byte(streamId & 0x000000ff >> 0),
+		},
+		Flags: f,
+		Data:  data,
+	}
+}
+
+// ReadFrame reads an entire frame into memory.
+func ReadFrame(r io.Reader) (f Frame, err os.Error) {
+	_, err = io.ReadFull(r, f.Header[:])
+	if err != nil {
+		return
+	}
+	err = binary.Read(r, binary.BigEndian, &f.Flags)
+	if err != nil {
+		return
+	}
+	var lengthField [3]byte
+	_, err = io.ReadFull(r, lengthField[:])
+	if err != nil {
+		if err == os.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+		return
+	}
+	var length uint32
+	length |= uint32(lengthField[0]) << 16
+	length |= uint32(lengthField[1]) << 8
+	length |= uint32(lengthField[2]) << 0
+	if length > 0 {
+		f.Data = make([]byte, int(length))
+		_, err = io.ReadFull(r, f.Data)
+		if err == os.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+	} else {
+		f.Data = []byte{}
+	}
+	return
+}
+
+// IsControl returns whether the frame holds a control frame.
+func (f Frame) IsControl() bool {
+	return f.Header[0]&0x80 != 0
+}
+
+// Type obtains the type field if the frame is a control frame, otherwise it returns zero.
+func (f Frame) Type() ControlFrameType {
+	if !f.IsControl() {
+		return 0
+	}
+	return (ControlFrameType(f.Header[2])<<8 | ControlFrameType(f.Header[3]))
+}
+
+// StreamId returns the stream ID field if the frame is a data frame, otherwise it returns zero.
+func (f Frame) StreamId() (id uint32) {
+	if f.IsControl() {
+		return 0
+	}
+	id |= uint32(f.Header[0]) << 24
+	id |= uint32(f.Header[1]) << 16
+	id |= uint32(f.Header[2]) << 8
+	id |= uint32(f.Header[3]) << 0
+	return
+}
+
+// WriteTo writes the frame in the SPDY format.
+func (f Frame) WriteTo(w io.Writer) (n int64, err os.Error) {
+	var nn int
+	// Header
+	nn, err = w.Write(f.Header[:])
+	n += int64(nn)
+	if err != nil {
+		return
+	}
+	// Flags
+	nn, err = w.Write([]byte{byte(f.Flags)})
+	n += int64(nn)
+	if err != nil {
+		return
+	}
+	// Length
+	nn, err = w.Write([]byte{
+		byte(len(f.Data) & 0x00ff0000 >> 16),
+		byte(len(f.Data) & 0x0000ff00 >> 8),
+		byte(len(f.Data) & 0x000000ff),
+	})
+	n += int64(nn)
+	if err != nil {
+		return
+	}
+	// Data
+	if len(f.Data) > 0 {
+		nn, err = w.Write(f.Data)
+		n += int64(nn)
+	}
+	return
+}
+
+// headerDictionary is the dictionary sent to the zlib compressor/decompressor.
+// Even though the specification states there is no null byte at the end, Chrome sends it.
+const headerDictionary = "optionsgetheadpostputdeletetrace" +
+	"acceptaccept-charsetaccept-encodingaccept-languageauthorizationexpectfromhost" +
+	"if-modified-sinceif-matchif-none-matchif-rangeif-unmodifiedsince" +
+	"max-forwardsproxy-authorizationrangerefererteuser-agent" +
+	"100101200201202203204205206300301302303304305306307400401402403404405406407408409410411412413414415416417500501502503504505" +
+	"accept-rangesageetaglocationproxy-authenticatepublicretry-after" +
+	"servervarywarningwww-authenticateallowcontent-basecontent-encodingcache-control" +
+	"connectiondatetrailertransfer-encodingupgradeviawarning" +
+	"content-languagecontent-lengthcontent-locationcontent-md5content-rangecontent-typeetagexpireslast-modifiedset-cookie" +
+	"MondayTuesdayWednesdayThursdayFridaySaturdaySunday" +
+	"JanFebMarAprMayJunJulAugSepOctNovDec" +
+	"chunkedtext/htmlimage/pngimage/jpgimage/gifapplication/xmlapplication/xhtmltext/plainpublicmax-age" +
+	"charset=iso-8859-1utf-8gzipdeflateHTTP/1.1statusversionurl\x00"
+
+// hrSource is a reader that passes through reads from another reader.
+// When the underlying reader reaches EOF, Read will block until another reader is added via change.
+type hrSource struct {
+	r io.Reader
+	m sync.RWMutex
+	c *sync.Cond
+}
+
+func (src *hrSource) Read(p []byte) (n int, err os.Error) {
+	src.m.RLock()
+	for src.r == nil {
+		src.c.Wait()
+	}
+	n, err = src.r.Read(p)
+	src.m.RUnlock()
+	if err == os.EOF {
+		src.change(nil)
+		err = nil
+	}
+	return
+}
+
+func (src *hrSource) change(r io.Reader) {
+	src.m.Lock()
+	defer src.m.Unlock()
+	src.r = r
+	src.c.Broadcast()
+}
+
+// A HeaderReader reads zlib-compressed headers.
+type HeaderReader struct {
+	source       hrSource
+	decompressor io.ReadCloser
+}
+
+// NewHeaderReader creates a HeaderReader with the initial dictionary.
+func NewHeaderReader() (hr *HeaderReader) {
+	hr = new(HeaderReader)
+	hr.source.c = sync.NewCond(hr.source.m.RLocker())
+	return
+}
+
+// ReadHeader reads a set of headers from a reader.
+func (hr *HeaderReader) ReadHeader(r io.Reader) (h http.Header, err os.Error) {
+	hr.source.change(r)
+	h, err = hr.read()
+	return
+}
+
+// Decode reads a set of headers from a block of bytes.
+func (hr *HeaderReader) Decode(data []byte) (h http.Header, err os.Error) {
+	hr.source.change(bytes.NewBuffer(data))
+	h, err = hr.read()
+	return
+}
+
+func (hr *HeaderReader) read() (h http.Header, err os.Error) {
+	var count uint16
+	if hr.decompressor == nil {
+		hr.decompressor, err = zlib.NewReaderDict(&hr.source, []byte(headerDictionary))
+		if err != nil {
+			return
+		}
+	}
+	err = binary.Read(hr.decompressor, binary.BigEndian, &count)
+	if err != nil {
+		return
+	}
+	h = make(http.Header, int(count))
+	for i := 0; i < int(count); i++ {
+		var name, value string
+		name, err = readHeaderString(hr.decompressor)
+		if err != nil {
+			return
+		}
+		value, err = readHeaderString(hr.decompressor)
+		if err != nil {
+			return
+		}
+		valueList := strings.Split(string(value), "\x00", -1)
+		for _, v := range valueList {
+			h.Add(name, v)
+		}
+	}
+	return
+}
+
+func readHeaderString(r io.Reader) (s string, err os.Error) {
+	var length uint16
+	err = binary.Read(r, binary.BigEndian, &length)
+	if err != nil {
+		return
+	}
+	data := make([]byte, int(length))
+	_, err = io.ReadFull(r, data)
+	if err != nil {
+		return
+	}
+	return string(data), nil
+}
+
+// HeaderWriter will write zlib-compressed headers on different streams.
+type HeaderWriter struct {
+	compressor *zlib.Writer
+	buffer     *bytes.Buffer
+}
+
+// NewHeaderWriter creates a HeaderWriter ready to compress headers.
+func NewHeaderWriter(level int) (hw *HeaderWriter) {
+	hw = &HeaderWriter{buffer: new(bytes.Buffer)}
+	hw.compressor, _ = zlib.NewWriterDict(hw.buffer, level, []byte(headerDictionary))
+	return
+}
+
+// WriteHeader writes a header block directly to an output.
+func (hw *HeaderWriter) WriteHeader(w io.Writer, h http.Header) (err os.Error) {
+	hw.write(h)
+	_, err = io.Copy(w, hw.buffer)
+	hw.buffer.Reset()
+	return
+}
+
+// Encode returns a compressed header block.
+func (hw *HeaderWriter) Encode(h http.Header) (data []byte) {
+	hw.write(h)
+	data = make([]byte, hw.buffer.Len())
+	hw.buffer.Read(data)
+	return
+}
+
+func (hw *HeaderWriter) write(h http.Header) {
+	binary.Write(hw.compressor, binary.BigEndian, uint16(len(h)))
+	for k, vals := range h {
+		k = strings.ToLower(k)
+		binary.Write(hw.compressor, binary.BigEndian, uint16(len(k)))
+		binary.Write(hw.compressor, binary.BigEndian, []byte(k))
+		v := strings.Join(vals, "\x00")
+		binary.Write(hw.compressor, binary.BigEndian, uint16(len(v)))
+		binary.Write(hw.compressor, binary.BigEndian, []byte(v))
+	}
+	hw.compressor.Flush()
+}

src/pkg/http/spdy/protocol_test.go

+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package spdy
+
+import (
+	"bytes"
+	"compress/zlib"
+	"http"
+	"os"
+	"testing"
+)
+
+type frameIoTest struct {
+	desc      string
+	data      []byte
+	frame     Frame
+	readError os.Error
+	readOnly  bool
+}
+
+var frameIoTests = []frameIoTest{
+	{
+		"noop frame",
+		[]byte{
+			0x80, 0x02, 0x00, 0x05,
+			0x00, 0x00, 0x00, 0x00,
+		},
+		ControlFrame(
+			TypeNoop,
+			0x00,
+			[]byte{},
+		),
+		nil,
+		false,
+	},
+	{
+		"ping frame",
+		[]byte{
+			0x80, 0x02, 0x00, 0x06,
+			0x00, 0x00, 0x00, 0x04,
+			0x00, 0x00, 0x00, 0x01,
+		},
+		ControlFrame(
+			TypePing,
+			0x00,
+			[]byte{0x00, 0x00, 0x00, 0x01},
+		),
+		nil,
+		false,
+	},
+	{
+		"syn_stream frame",
+		[]byte{
+			0x80, 0x02, 0x00, 0x01,
+			0x01, 0x00, 0x00, 0x53,
+			0x00, 0x00, 0x00, 0x01,
+			0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x78, 0xbb,
+			0xdf, 0xa2, 0x51, 0xb2,
+			0x62, 0x60, 0x66, 0x60,
+			0xcb, 0x4d, 0x2d, 0xc9,
+			0xc8, 0x4f, 0x61, 0x60,
+			0x4e, 0x4f, 0x2d, 0x61,
+			0x60, 0x2e, 0x2d, 0xca,
+			0x61, 0x10, 0xcb, 0x28,
+			0x29, 0x29, 0xb0, 0xd2,
+			0xd7, 0x2f, 0x2f, 0x2f,
+			0xd7, 0x4b, 0xcf, 0xcf,
+			0x4f, 0xcf, 0x49, 0xd5,
+			0x4b, 0xce, 0xcf, 0xd5,
+			0x67, 0x60, 0x2f, 0x4b,
+			0x2d, 0x2a, 0xce, 0xcc,
+			0xcf, 0x63, 0xe0, 0x00,
+			0x29, 0xd0, 0x37, 0xd4,
+			0x33, 0x04, 0x00, 0x00,
+			0x00, 0xff, 0xff,
+		},
+		ControlFrame(
+			TypeSynStream,
+			0x01,
+			[]byte{
+				0x00, 0x00, 0x00, 0x01,
+				0x00, 0x00, 0x00, 0x00,
+				0x00, 0x00, 0x78, 0xbb,
+				0xdf, 0xa2, 0x51, 0xb2,
+				0x62, 0x60, 0x66, 0x60,
+				0xcb, 0x4d, 0x2d, 0xc9,
+				0xc8, 0x4f, 0x61, 0x60,
+				0x4e, 0x4f, 0x2d, 0x61,
+				0x60, 0x2e, 0x2d, 0xca,
+				0x61, 0x10, 0xcb, 0x28,
+				0x29, 0x29, 0xb0, 0xd2,
+				0xd7, 0x2f, 0x2f, 0x2f,
+				0xd7, 0x4b, 0xcf, 0xcf,
+				0x4f, 0xcf, 0x49, 0xd5,
+				0x4b, 0xce, 0xcf, 0xd5,
+				0x67, 0x60, 0x2f, 0x4b,
+				0x2d, 0x2a, 0xce, 0xcc,
+				0xcf, 0x63, 0xe0, 0x00,
+				0x29, 0xd0, 0x37, 0xd4,
+				0x33, 0x04, 0x00, 0x00,
+				0x00, 0xff, 0xff,
+			},
+		),
+		nil,
+		false,
+	},
+	{
+		"data frame",
+		[]byte{
+			0x00, 0x00, 0x00, 0x05,
+			0x01, 0x00, 0x00, 0x04,
+			0x01, 0x02, 0x03, 0x04,
+		},
+		DataFrame(
+			5,
+			0x01,
+			[]byte{0x01, 0x02, 0x03, 0x04},
+		),
+		nil,
+		false,
+	},
+	{
+		"too much data",
+		[]byte{
+			0x00, 0x00, 0x00, 0x05,
+			0x01, 0x00, 0x00, 0x04,
+			0x01, 0x02, 0x03, 0x04,
+			0x05, 0x06, 0x07, 0x08,
+		},
+		DataFrame(
+			5,
+			0x01,
+			[]byte{0x01, 0x02, 0x03, 0x04},
+		),
+		nil,
+		true,
+	},
+	{
+		"not enough data",
+		[]byte{
+			0x00, 0x00, 0x00, 0x05,
+		},
+		Frame{},
+		os.EOF,
+		true,
+	},
+}
+
+func TestReadFrame(t *testing.T) {
+	for _, tt := range frameIoTests {
+		f, err := ReadFrame(bytes.NewBuffer(tt.data))
+		if err != tt.readError {
+			t.Errorf("%s: ReadFrame: %s", tt.desc, err)
+			continue
+		}
+		if err == nil {
+			if !bytes.Equal(f.Header[:], tt.frame.Header[:]) {
+				t.Errorf("%s: header %q != %q", tt.desc, string(f.Header[:]), string(tt.frame.Header[:]))
+			}
+			if f.Flags != tt.frame.Flags {
+				t.Errorf("%s: flags %#02x != %#02x", tt.desc, f.Flags, tt.frame.Flags)
+			}
+			if !bytes.Equal(f.Data, tt.frame.Data) {
+				t.Errorf("%s: data %q != %q", tt.desc, string(f.Data), string(tt.frame.Data))
+			}
+		}
+	}
+}
+
+func TestWriteTo(t *testing.T) {
+	for _, tt := range frameIoTests {
+		if tt.readOnly {
+			continue
+		}
+		b := new(bytes.Buffer)
+		_, err := tt.frame.WriteTo(b)
+		if err != nil {
+			t.Errorf("%s: WriteTo: %s", tt.desc, err)
+		}
+		if !bytes.Equal(b.Bytes(), tt.data) {
+			t.Errorf("%s: data %q != %q", tt.desc, string(b.Bytes()), string(tt.data))
+		}
+	}
+}
+
+var headerDataTest = []byte{
+	0x78, 0xbb, 0xdf, 0xa2,
+	0x51, 0xb2, 0x62, 0x60,
+	0x66, 0x60, 0xcb, 0x4d,
+	0x2d, 0xc9, 0xc8, 0x4f,
+	0x61, 0x60, 0x4e, 0x4f,
+	0x2d, 0x61, 0x60, 0x2e,
+	0x2d, 0xca, 0x61, 0x10,
+	0xcb, 0x28, 0x29, 0x29,
+	0xb0, 0xd2, 0xd7, 0x2f,
+	0x2f, 0x2f, 0xd7, 0x4b,
+	0xcf, 0xcf, 0x4f, 0xcf,
+	0x49, 0xd5, 0x4b, 0xce,
+	0xcf, 0xd5, 0x67, 0x60,
+	0x2f, 0x4b, 0x2d, 0x2a,
+	0xce, 0xcc, 0xcf, 0x63,
+	0xe0, 0x00, 0x29, 0xd0,
+	0x37, 0xd4, 0x33, 0x04,
+	0x00, 0x00, 0x00, 0xff,
+	0xff,
+}
+
+func TestReadHeader(t *testing.T) {
+	r := NewHeaderReader()
+	h, err := r.Decode(headerDataTest)
+	if err != nil {
+		t.Fatalf("Error: %v", err)
+		return
+	}
+	if len(h) != 3 {
+		t.Errorf("Header count = %d (expected 3)", len(h))
+	}
+	if h.Get("Url") != "http://www.google.com/" {
+		t.Errorf("Url: %q != %q", h.Get("Url"), "http://www.google.com/")
+	}
+	if h.Get("Method") != "get" {
+		t.Errorf("Method: %q != %q", h.Get("Method"), "get")
+	}
+	if h.Get("Version") != "http/1.1" {
+		t.Errorf("Version: %q != %q", h.Get("Version"), "http/1.1")
+	}
+}
+
+func TestWriteHeader(t *testing.T) {
+	for level := zlib.NoCompression; level <= zlib.BestCompression; level++ {
+		r := NewHeaderReader()
+		w := NewHeaderWriter(level)
+		for i := 0; i < 100; i++ {
+			b := new(bytes.Buffer)
+			gold := http.Header{
+				"Url":     []string{"http://www.google.com/"},
+				"Method":  []string{"get"},
+				"Version": []string{"http/1.1"},
+			}
+			w.WriteHeader(b, gold)
+			h, err := r.Decode(b.Bytes())
+			if err != nil {
+				t.Errorf("(level=%d i=%d) Error: %v", level, i, err)
+				return
+			}
+			if len(h) != len(gold) {
+				t.Errorf("(level=%d i=%d) Header count = %d (expected %d)", level, i, len(h), len(gold))
+			}
+			for k, _ := range h {
+				if h.Get(k) != gold.Get(k) {
+					t.Errorf("(level=%d i=%d) %s: %q != %q", level, i, k, h.Get(k), gold.Get(k))
+				}
+			}
+		}
+	}
+}