blob: 67b874d6b5c6e279991c653ce45767ef861f0187 [file] [log] [blame]
// Copyright 2015 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.
// See https://code.google.com/p/go/source/browse/CONTRIBUTORS
// Licensed under the same terms as Go itself:
// https://code.google.com/p/go/source/browse/LICENSE
/*
The h2i command is an interactive HTTP/2 console.
Usage:
$ h2i [flags] <hostname>
Interactive commands in the console: (all parts case-insensitive)
ping [data]
settings ack
settings FOO=n BAR=z
headers (open a new stream by typing HTTP/1.1)
*/
package main
import (
"bufio"
"bytes"
"crypto/tls"
"errors"
"flag"
"fmt"
"io"
"log"
"net"
"net/http"
"os"
"regexp"
"strconv"
"strings"
"github.com/bradfitz/http2"
"github.com/bradfitz/http2/hpack"
"golang.org/x/crypto/ssh/terminal"
)
// Flags
var (
flagNextProto = flag.String("nextproto", "h2,h2-14", "Comma-separated list of NPN/ALPN protocol names to negotiate.")
flagInsecure = flag.Bool("insecure", false, "Whether to skip TLS cert validation")
)
type command struct {
run func(*h2i, []string) error // required
// complete optionally specifies tokens (case-insensitive) which are
// valid for this subcommand.
complete func() []string
}
var commands = map[string]command{
"ping": command{run: (*h2i).cmdPing},
"settings": command{
run: (*h2i).cmdSettings,
complete: func() []string {
return []string{
"ACK",
http2.SettingHeaderTableSize.String(),
http2.SettingEnablePush.String(),
http2.SettingMaxConcurrentStreams.String(),
http2.SettingInitialWindowSize.String(),
http2.SettingMaxFrameSize.String(),
http2.SettingMaxHeaderListSize.String(),
}
},
},
"quit": command{run: (*h2i).cmdQuit},
"headers": command{run: (*h2i).cmdHeaders},
}
func usage() {
fmt.Fprintf(os.Stderr, "Usage: h2i <hostname>\n\n")
flag.PrintDefaults()
os.Exit(1)
}
// withPort adds ":443" if another port isn't already present.
func withPort(host string) string {
if _, _, err := net.SplitHostPort(host); err != nil {
return net.JoinHostPort(host, "443")
}
return host
}
// h2i is the app's state.
type h2i struct {
host string
tc *tls.Conn
framer *http2.Framer
term *terminal.Terminal
// owned by the command loop:
streamID uint32
hbuf bytes.Buffer
henc *hpack.Encoder
// owned by the readFrames loop:
peerSetting map[http2.SettingID]uint32
hdec *hpack.Decoder
}
func main() {
flag.Usage = usage
flag.Parse()
if flag.NArg() != 1 {
usage()
}
log.SetFlags(0)
host := flag.Arg(0)
app := &h2i{
host: host,
peerSetting: make(map[http2.SettingID]uint32),
}
app.henc = hpack.NewEncoder(&app.hbuf)
if err := app.Main(); err != nil {
if app.term != nil {
app.logf("%v\n", err)
} else {
fmt.Fprintf(os.Stderr, "%v\n", err)
}
os.Exit(1)
}
fmt.Fprintf(os.Stdout, "\n")
}
func (app *h2i) Main() error {
cfg := &tls.Config{
ServerName: app.host,
NextProtos: strings.Split(*flagNextProto, ","),
InsecureSkipVerify: *flagInsecure,
}
hostAndPort := withPort(app.host)
log.Printf("Connecting to %s ...", hostAndPort)
tc, err := tls.Dial("tcp", hostAndPort, cfg)
if err != nil {
return fmt.Errorf("Error dialing %s: %v", withPort(app.host), err)
}
log.Printf("Connected to %v", tc.RemoteAddr())
defer tc.Close()
if err := tc.Handshake(); err != nil {
return fmt.Errorf("TLS handshake: %v", err)
}
if !*flagInsecure {
if err := tc.VerifyHostname(app.host); err != nil {
return fmt.Errorf("VerifyHostname: %v", err)
}
}
state := tc.ConnectionState()
log.Printf("Negotiated protocol %q", state.NegotiatedProtocol)
if !state.NegotiatedProtocolIsMutual || state.NegotiatedProtocol == "" {
return fmt.Errorf("Could not negotiate protocol mutually")
}
if _, err := io.WriteString(tc, http2.ClientPreface); err != nil {
return err
}
app.framer = http2.NewFramer(tc, tc)
oldState, err := terminal.MakeRaw(0)
if err != nil {
return err
}
defer terminal.Restore(0, oldState)
var screen = struct {
io.Reader
io.Writer
}{os.Stdin, os.Stdout}
app.term = terminal.NewTerminal(screen, "h2i> ")
lastWord := regexp.MustCompile(`.+\W(\w+)$`)
app.term.AutoCompleteCallback = func(line string, pos int, key rune) (newLine string, newPos int, ok bool) {
if key != '\t' {
return
}
if pos != len(line) {
// TODO: we're being lazy for now, only supporting tab completion at the end.
return
}
// Auto-complete for the command itself.
if !strings.Contains(line, " ") {
var name string
name, _, ok = lookupCommand(line)
if !ok {
return
}
return name, len(name), true
}
_, c, ok := lookupCommand(line[:strings.IndexByte(line, ' ')])
if !ok || c.complete == nil {
return
}
if strings.HasSuffix(line, " ") {
app.logf("%s", strings.Join(c.complete(), " "))
return line, pos, true
}
m := lastWord.FindStringSubmatch(line)
if m == nil {
return line, len(line), true
}
soFar := m[1]
var match []string
for _, cand := range c.complete() {
if len(soFar) > len(cand) || !strings.EqualFold(cand[:len(soFar)], soFar) {
continue
}
match = append(match, cand)
}
if len(match) == 0 {
return
}
if len(match) > 1 {
// TODO: auto-complete any common prefix
app.logf("%s", strings.Join(match, " "))
return line, pos, true
}
newLine = line[:len(line)-len(soFar)] + match[0]
return newLine, len(newLine), true
}
errc := make(chan error, 2)
go func() { errc <- app.readFrames() }()
go func() { errc <- app.readConsole() }()
return <-errc
}
func (app *h2i) logf(format string, args ...interface{}) {
fmt.Fprintf(app.term, format+"\n", args...)
}
func (app *h2i) readConsole() error {
for {
line, err := app.term.ReadLine()
if err == io.EOF {
return nil
}
if err != nil {
return fmt.Errorf("terminal.ReadLine: %v", err)
}
f := strings.Fields(line)
if len(f) == 0 {
continue
}
cmd, args := f[0], f[1:]
if _, c, ok := lookupCommand(cmd); ok {
err = c.run(app, args)
} else {
app.logf("Unknown command %q", line)
}
if err == errExitApp {
return nil
}
if err != nil {
return err
}
}
}
func lookupCommand(prefix string) (name string, c command, ok bool) {
prefix = strings.ToLower(prefix)
if c, ok = commands[prefix]; ok {
return prefix, c, ok
}
for full, candidate := range commands {
if strings.HasPrefix(full, prefix) {
if c.run != nil {
return "", command{}, false // ambiguous
}
c = candidate
name = full
}
}
return name, c, c.run != nil
}
var errExitApp = errors.New("internal sentinel error value to quit the console reading loop")
func (a *h2i) cmdQuit(args []string) error {
if len(args) > 0 {
a.logf("the QUIT command takes no argument")
return nil
}
return errExitApp
}
func (a *h2i) cmdSettings(args []string) error {
if len(args) == 1 && strings.EqualFold(args[0], "ACK") {
return a.framer.WriteSettingsAck()
}
var settings []http2.Setting
for _, arg := range args {
if strings.EqualFold(arg, "ACK") {
a.logf("Error: ACK must be only argument with the SETTINGS command")
return nil
}
eq := strings.Index(arg, "=")
if eq == -1 {
a.logf("Error: invalid argument %q (expected SETTING_NAME=nnnn)", arg)
return nil
}
sid, ok := settingByName(arg[:eq])
if !ok {
a.logf("Error: unknown setting name %q", arg[:eq])
return nil
}
val, err := strconv.ParseUint(arg[eq+1:], 10, 32)
if err != nil {
a.logf("Error: invalid argument %q (expected SETTING_NAME=nnnn)", arg)
return nil
}
settings = append(settings, http2.Setting{
ID: sid,
Val: uint32(val),
})
}
a.logf("Sending: %v", settings)
return a.framer.WriteSettings(settings...)
}
func settingByName(name string) (http2.SettingID, bool) {
for _, sid := range [...]http2.SettingID{
http2.SettingHeaderTableSize,
http2.SettingEnablePush,
http2.SettingMaxConcurrentStreams,
http2.SettingInitialWindowSize,
http2.SettingMaxFrameSize,
http2.SettingMaxHeaderListSize,
} {
if strings.EqualFold(sid.String(), name) {
return sid, true
}
}
return 0, false
}
func (app *h2i) cmdPing(args []string) error {
if len(args) > 1 {
app.logf("invalid PING usage: only accepts 0 or 1 args")
return nil // nil means don't end the program
}
var data [8]byte
if len(args) == 1 {
copy(data[:], args[0])
} else {
copy(data[:], "h2i_ping")
}
return app.framer.WritePing(false, data)
}
func (app *h2i) cmdHeaders(args []string) error {
if len(args) > 0 {
app.logf("Error: HEADERS doesn't yet take arguments.")
// TODO: flags for restricting window size, to force CONTINUATION
// frames.
return nil
}
var h1req bytes.Buffer
app.term.SetPrompt("(as HTTP/1.1)> ")
defer app.term.SetPrompt("h2i> ")
for {
line, err := app.term.ReadLine()
if err != nil {
return err
}
h1req.WriteString(line)
h1req.WriteString("\r\n")
if line == "" {
break
}
}
req, err := http.ReadRequest(bufio.NewReader(&h1req))
if err != nil {
app.logf("Invalid HTTP/1.1 request: %v", err)
return nil
}
if app.streamID == 0 {
app.streamID = 1
} else {
app.streamID += 2
}
app.logf("Opening Stream-ID %d:", app.streamID)
hbf := app.encodeHeaders(req)
if len(hbf) > 16<<10 {
app.logf("TODO: h2i doesn't yet write CONTINUATION frames. Copy it from transport.go")
return nil
}
return app.framer.WriteHeaders(http2.HeadersFrameParam{
StreamID: app.streamID,
BlockFragment: hbf,
EndStream: req.Method == "GET" || req.Method == "HEAD", // good enough for now
EndHeaders: true, // for now
})
}
func (app *h2i) readFrames() error {
for {
f, err := app.framer.ReadFrame()
if err != nil {
return fmt.Errorf("ReadFrame: %v", err)
}
app.logf("%v", f)
switch f := f.(type) {
case *http2.PingFrame:
app.logf(" Data = %q", f.Data)
case *http2.SettingsFrame:
f.ForeachSetting(func(s http2.Setting) error {
app.logf(" %v", s)
app.peerSetting[s.ID] = s.Val
return nil
})
case *http2.WindowUpdateFrame:
app.logf(" Window-Increment = %v\n", f.Increment)
case *http2.GoAwayFrame:
app.logf(" Last-Stream-ID = %d; Error-Code = %v (%d)\n", f.LastStreamID, f.ErrCode, f.ErrCode)
case *http2.DataFrame:
app.logf(" %q", f.Data())
case *http2.HeadersFrame:
if f.HasPriority() {
app.logf(" PRIORITY = %v", f.Priority)
}
if app.hdec == nil {
// TODO: if the user uses h2i to send a SETTINGS frame advertising
// something larger, we'll need to respect SETTINGS_HEADER_TABLE_SIZE
// and stuff here instead of using the 4k default. But for now:
tableSize := uint32(4 << 10)
app.hdec = hpack.NewDecoder(tableSize, app.onNewHeaderField)
}
app.hdec.Write(f.HeaderBlockFragment())
}
}
}
// called from readLoop
func (app *h2i) onNewHeaderField(f hpack.HeaderField) {
if f.Sensitive {
app.logf(" %s = %q (SENSITIVE)", f.Name, f.Value)
}
app.logf(" %s = %q", f.Name, f.Value)
}
func (app *h2i) encodeHeaders(req *http.Request) []byte {
app.hbuf.Reset()
// TODO(bradfitz): figure out :authority-vs-Host stuff between http2 and Go
host := req.Host
if host == "" {
host = req.URL.Host
}
path := req.URL.Path
if path == "" {
path = "/"
}
app.writeHeader(":authority", host) // probably not right for all sites
app.writeHeader(":method", req.Method)
app.writeHeader(":path", path)
app.writeHeader(":scheme", "https")
for k, vv := range req.Header {
lowKey := strings.ToLower(k)
if lowKey == "host" {
continue
}
for _, v := range vv {
app.writeHeader(lowKey, v)
}
}
return app.hbuf.Bytes()
}
func (app *h2i) writeHeader(name, value string) {
app.henc.WriteField(hpack.HeaderField{Name: name, Value: value})
app.logf(" %s = %s", name, value)
}