cloudflared-mirror/vendor/github.com/gobwas/ws/http.go

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package ws
import (
"bufio"
"bytes"
"io"
"net/http"
"net/url"
"strconv"
"github.com/gobwas/httphead"
)
const (
crlf = "\r\n"
colonAndSpace = ": "
commaAndSpace = ", "
)
const (
textHeadUpgrade = "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\n"
)
var (
textHeadBadRequest = statusText(http.StatusBadRequest)
textHeadInternalServerError = statusText(http.StatusInternalServerError)
textHeadUpgradeRequired = statusText(http.StatusUpgradeRequired)
textTailErrHandshakeBadProtocol = errorText(ErrHandshakeBadProtocol)
textTailErrHandshakeBadMethod = errorText(ErrHandshakeBadMethod)
textTailErrHandshakeBadHost = errorText(ErrHandshakeBadHost)
textTailErrHandshakeBadUpgrade = errorText(ErrHandshakeBadUpgrade)
textTailErrHandshakeBadConnection = errorText(ErrHandshakeBadConnection)
textTailErrHandshakeBadSecAccept = errorText(ErrHandshakeBadSecAccept)
textTailErrHandshakeBadSecKey = errorText(ErrHandshakeBadSecKey)
textTailErrHandshakeBadSecVersion = errorText(ErrHandshakeBadSecVersion)
textTailErrUpgradeRequired = errorText(ErrHandshakeUpgradeRequired)
)
const (
// Every new header must be added to TestHeaderNames test.
headerHost = "Host"
headerUpgrade = "Upgrade"
headerConnection = "Connection"
headerSecVersion = "Sec-WebSocket-Version"
headerSecProtocol = "Sec-WebSocket-Protocol"
headerSecExtensions = "Sec-WebSocket-Extensions"
headerSecKey = "Sec-WebSocket-Key"
headerSecAccept = "Sec-WebSocket-Accept"
headerHostCanonical = headerHost
headerUpgradeCanonical = headerUpgrade
headerConnectionCanonical = headerConnection
headerSecVersionCanonical = "Sec-Websocket-Version"
headerSecProtocolCanonical = "Sec-Websocket-Protocol"
headerSecExtensionsCanonical = "Sec-Websocket-Extensions"
headerSecKeyCanonical = "Sec-Websocket-Key"
headerSecAcceptCanonical = "Sec-Websocket-Accept"
)
var (
specHeaderValueUpgrade = []byte("websocket")
specHeaderValueConnection = []byte("Upgrade")
specHeaderValueConnectionLower = []byte("upgrade")
specHeaderValueSecVersion = []byte("13")
)
var (
httpVersion1_0 = []byte("HTTP/1.0")
httpVersion1_1 = []byte("HTTP/1.1")
httpVersionPrefix = []byte("HTTP/")
)
type httpRequestLine struct {
method, uri []byte
major, minor int
}
type httpResponseLine struct {
major, minor int
status int
reason []byte
}
// httpParseRequestLine parses http request line like "GET / HTTP/1.0".
func httpParseRequestLine(line []byte) (req httpRequestLine, err error) {
var proto []byte
req.method, req.uri, proto = bsplit3(line, ' ')
var ok bool
req.major, req.minor, ok = httpParseVersion(proto)
if !ok {
err = ErrMalformedRequest
}
return req, err
}
func httpParseResponseLine(line []byte) (resp httpResponseLine, err error) {
var (
proto []byte
status []byte
)
proto, status, resp.reason = bsplit3(line, ' ')
var ok bool
resp.major, resp.minor, ok = httpParseVersion(proto)
if !ok {
return resp, ErrMalformedResponse
}
var convErr error
resp.status, convErr = asciiToInt(status)
if convErr != nil {
return resp, ErrMalformedResponse
}
return resp, nil
}
// httpParseVersion parses major and minor version of HTTP protocol. It returns
// parsed values and true if parse is ok.
func httpParseVersion(bts []byte) (major, minor int, ok bool) {
switch {
case bytes.Equal(bts, httpVersion1_0):
return 1, 0, true
case bytes.Equal(bts, httpVersion1_1):
return 1, 1, true
case len(bts) < 8:
return 0, 0, false
case !bytes.Equal(bts[:5], httpVersionPrefix):
return 0, 0, false
}
bts = bts[5:]
dot := bytes.IndexByte(bts, '.')
if dot == -1 {
return 0, 0, false
}
var err error
major, err = asciiToInt(bts[:dot])
if err != nil {
return major, 0, false
}
minor, err = asciiToInt(bts[dot+1:])
if err != nil {
return major, minor, false
}
return major, minor, true
}
// httpParseHeaderLine parses HTTP header as key-value pair. It returns parsed
// values and true if parse is ok.
func httpParseHeaderLine(line []byte) (k, v []byte, ok bool) {
colon := bytes.IndexByte(line, ':')
if colon == -1 {
return nil, nil, false
}
k = btrim(line[:colon])
// TODO(gobwas): maybe use just lower here?
canonicalizeHeaderKey(k)
v = btrim(line[colon+1:])
return k, v, true
}
// httpGetHeader is the same as textproto.MIMEHeader.Get, except the thing,
// that key is already canonical. This helps to increase performance.
func httpGetHeader(h http.Header, key string) string {
if h == nil {
return ""
}
v := h[key]
if len(v) == 0 {
return ""
}
return v[0]
}
// The request MAY include a header field with the name
// |Sec-WebSocket-Protocol|. If present, this value indicates one or more
// comma-separated subprotocol the client wishes to speak, ordered by
// preference. The elements that comprise this value MUST be non-empty strings
// with characters in the range U+0021 to U+007E not including separator
// characters as defined in [RFC2616] and MUST all be unique strings. The ABNF
// for the value of this header field is 1#token, where the definitions of
// constructs and rules are as given in [RFC2616].
func strSelectProtocol(h string, check func(string) bool) (ret string, ok bool) {
ok = httphead.ScanTokens(strToBytes(h), func(v []byte) bool {
if check(btsToString(v)) {
ret = string(v)
return false
}
return true
})
return ret, ok
}
func btsSelectProtocol(h []byte, check func([]byte) bool) (ret string, ok bool) {
var selected []byte
ok = httphead.ScanTokens(h, func(v []byte) bool {
if check(v) {
selected = v
return false
}
return true
})
if ok && selected != nil {
return string(selected), true
}
return ret, ok
}
func btsSelectExtensions(h []byte, selected []httphead.Option, check func(httphead.Option) bool) ([]httphead.Option, bool) {
s := httphead.OptionSelector{
Flags: httphead.SelectCopy,
Check: check,
}
return s.Select(h, selected)
}
func negotiateMaybe(in httphead.Option, dest []httphead.Option, f func(httphead.Option) (httphead.Option, error)) ([]httphead.Option, error) {
if in.Size() == 0 {
return dest, nil
}
opt, err := f(in)
if err != nil {
return nil, err
}
if opt.Size() > 0 {
dest = append(dest, opt)
}
return dest, nil
}
func negotiateExtensions(
h []byte, dest []httphead.Option,
f func(httphead.Option) (httphead.Option, error),
) (_ []httphead.Option, err error) {
index := -1
var current httphead.Option
ok := httphead.ScanOptions(h, func(i int, name, attr, val []byte) httphead.Control {
if i != index {
dest, err = negotiateMaybe(current, dest, f)
if err != nil {
return httphead.ControlBreak
}
index = i
current = httphead.Option{Name: name}
}
if attr != nil {
current.Parameters.Set(attr, val)
}
return httphead.ControlContinue
})
if !ok {
return nil, ErrMalformedRequest
}
return negotiateMaybe(current, dest, f)
}
func httpWriteHeader(bw *bufio.Writer, key, value string) {
httpWriteHeaderKey(bw, key)
bw.WriteString(value)
bw.WriteString(crlf)
}
func httpWriteHeaderBts(bw *bufio.Writer, key string, value []byte) {
httpWriteHeaderKey(bw, key)
bw.Write(value)
bw.WriteString(crlf)
}
func httpWriteHeaderKey(bw *bufio.Writer, key string) {
bw.WriteString(key)
bw.WriteString(colonAndSpace)
}
func httpWriteUpgradeRequest(
bw *bufio.Writer,
u *url.URL,
nonce []byte,
protocols []string,
extensions []httphead.Option,
header HandshakeHeader,
) {
bw.WriteString("GET ")
bw.WriteString(u.RequestURI())
bw.WriteString(" HTTP/1.1\r\n")
httpWriteHeader(bw, headerHost, u.Host)
httpWriteHeaderBts(bw, headerUpgrade, specHeaderValueUpgrade)
httpWriteHeaderBts(bw, headerConnection, specHeaderValueConnection)
httpWriteHeaderBts(bw, headerSecVersion, specHeaderValueSecVersion)
// NOTE: write nonce bytes as a string to prevent heap allocation
// WriteString() copy given string into its inner buffer, unlike Write()
// which may write p directly to the underlying io.Writer which in turn
// will lead to p escape.
httpWriteHeader(bw, headerSecKey, btsToString(nonce))
if len(protocols) > 0 {
httpWriteHeaderKey(bw, headerSecProtocol)
for i, p := range protocols {
if i > 0 {
bw.WriteString(commaAndSpace)
}
bw.WriteString(p)
}
bw.WriteString(crlf)
}
if len(extensions) > 0 {
httpWriteHeaderKey(bw, headerSecExtensions)
httphead.WriteOptions(bw, extensions)
bw.WriteString(crlf)
}
if header != nil {
header.WriteTo(bw)
}
bw.WriteString(crlf)
}
func httpWriteResponseUpgrade(bw *bufio.Writer, nonce []byte, hs Handshake, header HandshakeHeaderFunc) {
bw.WriteString(textHeadUpgrade)
httpWriteHeaderKey(bw, headerSecAccept)
writeAccept(bw, nonce)
bw.WriteString(crlf)
if hs.Protocol != "" {
httpWriteHeader(bw, headerSecProtocol, hs.Protocol)
}
if len(hs.Extensions) > 0 {
httpWriteHeaderKey(bw, headerSecExtensions)
httphead.WriteOptions(bw, hs.Extensions)
bw.WriteString(crlf)
}
if header != nil {
header(bw)
}
bw.WriteString(crlf)
}
func httpWriteResponseError(bw *bufio.Writer, err error, code int, header HandshakeHeaderFunc) {
switch code {
case http.StatusBadRequest:
bw.WriteString(textHeadBadRequest)
case http.StatusInternalServerError:
bw.WriteString(textHeadInternalServerError)
case http.StatusUpgradeRequired:
bw.WriteString(textHeadUpgradeRequired)
default:
writeStatusText(bw, code)
}
// Write custom headers.
if header != nil {
header(bw)
}
switch err {
case ErrHandshakeBadProtocol:
bw.WriteString(textTailErrHandshakeBadProtocol)
case ErrHandshakeBadMethod:
bw.WriteString(textTailErrHandshakeBadMethod)
case ErrHandshakeBadHost:
bw.WriteString(textTailErrHandshakeBadHost)
case ErrHandshakeBadUpgrade:
bw.WriteString(textTailErrHandshakeBadUpgrade)
case ErrHandshakeBadConnection:
bw.WriteString(textTailErrHandshakeBadConnection)
case ErrHandshakeBadSecAccept:
bw.WriteString(textTailErrHandshakeBadSecAccept)
case ErrHandshakeBadSecKey:
bw.WriteString(textTailErrHandshakeBadSecKey)
case ErrHandshakeBadSecVersion:
bw.WriteString(textTailErrHandshakeBadSecVersion)
case ErrHandshakeUpgradeRequired:
bw.WriteString(textTailErrUpgradeRequired)
case nil:
bw.WriteString(crlf)
default:
writeErrorText(bw, err)
}
}
func writeStatusText(bw *bufio.Writer, code int) {
bw.WriteString("HTTP/1.1 ")
bw.WriteString(strconv.Itoa(code))
bw.WriteByte(' ')
bw.WriteString(http.StatusText(code))
bw.WriteString(crlf)
bw.WriteString("Content-Type: text/plain; charset=utf-8")
bw.WriteString(crlf)
}
func writeErrorText(bw *bufio.Writer, err error) {
body := err.Error()
bw.WriteString("Content-Length: ")
bw.WriteString(strconv.Itoa(len(body)))
bw.WriteString(crlf)
bw.WriteString(crlf)
bw.WriteString(body)
}
// httpError is like the http.Error with WebSocket context exception.
func httpError(w http.ResponseWriter, body string, code int) {
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
w.Header().Set("Content-Length", strconv.Itoa(len(body)))
w.WriteHeader(code)
w.Write([]byte(body))
}
// statusText is a non-performant status text generator.
// NOTE: Used only to generate constants.
func statusText(code int) string {
var buf bytes.Buffer
bw := bufio.NewWriter(&buf)
writeStatusText(bw, code)
bw.Flush()
return buf.String()
}
// errorText is a non-performant error text generator.
// NOTE: Used only to generate constants.
func errorText(err error) string {
var buf bytes.Buffer
bw := bufio.NewWriter(&buf)
writeErrorText(bw, err)
bw.Flush()
return buf.String()
}
// HandshakeHeader is the interface that writes both upgrade request or
// response headers into a given io.Writer.
type HandshakeHeader interface {
io.WriterTo
}
// HandshakeHeaderString is an adapter to allow the use of headers represented
// by ordinary string as HandshakeHeader.
type HandshakeHeaderString string
// WriteTo implements HandshakeHeader (and io.WriterTo) interface.
func (s HandshakeHeaderString) WriteTo(w io.Writer) (int64, error) {
n, err := io.WriteString(w, string(s))
return int64(n), err
}
// HandshakeHeaderBytes is an adapter to allow the use of headers represented
// by ordinary slice of bytes as HandshakeHeader.
type HandshakeHeaderBytes []byte
// WriteTo implements HandshakeHeader (and io.WriterTo) interface.
func (b HandshakeHeaderBytes) WriteTo(w io.Writer) (int64, error) {
n, err := w.Write(b)
return int64(n), err
}
// HandshakeHeaderFunc is an adapter to allow the use of headers represented by
// ordinary function as HandshakeHeader.
type HandshakeHeaderFunc func(io.Writer) (int64, error)
// WriteTo implements HandshakeHeader (and io.WriterTo) interface.
func (f HandshakeHeaderFunc) WriteTo(w io.Writer) (int64, error) {
return f(w)
}
// HandshakeHeaderHTTP is an adapter to allow the use of http.Header as
// HandshakeHeader.
type HandshakeHeaderHTTP http.Header
// WriteTo implements HandshakeHeader (and io.WriterTo) interface.
func (h HandshakeHeaderHTTP) WriteTo(w io.Writer) (int64, error) {
wr := writer{w: w}
err := http.Header(h).Write(&wr)
return wr.n, err
}
type writer struct {
n int64
w io.Writer
}
func (w *writer) WriteString(s string) (int, error) {
n, err := io.WriteString(w.w, s)
w.n += int64(n)
return n, err
}
func (w *writer) Write(p []byte) (int, error) {
n, err := w.w.Write(p)
w.n += int64(n)
return n, err
}