From 2f0b35e3c25bc4394f3288e1baa77d250cb510ed Mon Sep 17 00:00:00 2001 From: Jordan Date: Thu, 10 Feb 2022 19:10:54 -0700 Subject: misc: go mod vendor --- vendor/github.com/gorilla/websocket/server.go | 363 ++++++++++++++++++++++++++ 1 file changed, 363 insertions(+) create mode 100644 vendor/github.com/gorilla/websocket/server.go (limited to 'vendor/github.com/gorilla/websocket/server.go') diff --git a/vendor/github.com/gorilla/websocket/server.go b/vendor/github.com/gorilla/websocket/server.go new file mode 100644 index 0000000..a761824 --- /dev/null +++ b/vendor/github.com/gorilla/websocket/server.go @@ -0,0 +1,363 @@ +// Copyright 2013 The Gorilla WebSocket 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 websocket + +import ( + "bufio" + "errors" + "io" + "net/http" + "net/url" + "strings" + "time" +) + +// HandshakeError describes an error with the handshake from the peer. +type HandshakeError struct { + message string +} + +func (e HandshakeError) Error() string { return e.message } + +// Upgrader specifies parameters for upgrading an HTTP connection to a +// WebSocket connection. +type Upgrader struct { + // HandshakeTimeout specifies the duration for the handshake to complete. + HandshakeTimeout time.Duration + + // ReadBufferSize and WriteBufferSize specify I/O buffer sizes. If a buffer + // size is zero, then buffers allocated by the HTTP server are used. The + // I/O buffer sizes do not limit the size of the messages that can be sent + // or received. + ReadBufferSize, WriteBufferSize int + + // WriteBufferPool is a pool of buffers for write operations. If the value + // is not set, then write buffers are allocated to the connection for the + // lifetime of the connection. + // + // A pool is most useful when the application has a modest volume of writes + // across a large number of connections. + // + // Applications should use a single pool for each unique value of + // WriteBufferSize. + WriteBufferPool BufferPool + + // Subprotocols specifies the server's supported protocols in order of + // preference. If this field is not nil, then the Upgrade method negotiates a + // subprotocol by selecting the first match in this list with a protocol + // requested by the client. If there's no match, then no protocol is + // negotiated (the Sec-Websocket-Protocol header is not included in the + // handshake response). + Subprotocols []string + + // Error specifies the function for generating HTTP error responses. If Error + // is nil, then http.Error is used to generate the HTTP response. + Error func(w http.ResponseWriter, r *http.Request, status int, reason error) + + // CheckOrigin returns true if the request Origin header is acceptable. If + // CheckOrigin is nil, then a safe default is used: return false if the + // Origin request header is present and the origin host is not equal to + // request Host header. + // + // A CheckOrigin function should carefully validate the request origin to + // prevent cross-site request forgery. + CheckOrigin func(r *http.Request) bool + + // EnableCompression specify if the server should attempt to negotiate per + // message compression (RFC 7692). Setting this value to true does not + // guarantee that compression will be supported. Currently only "no context + // takeover" modes are supported. + EnableCompression bool +} + +func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status int, reason string) (*Conn, error) { + err := HandshakeError{reason} + if u.Error != nil { + u.Error(w, r, status, err) + } else { + w.Header().Set("Sec-Websocket-Version", "13") + http.Error(w, http.StatusText(status), status) + } + return nil, err +} + +// checkSameOrigin returns true if the origin is not set or is equal to the request host. +func checkSameOrigin(r *http.Request) bool { + origin := r.Header["Origin"] + if len(origin) == 0 { + return true + } + u, err := url.Parse(origin[0]) + if err != nil { + return false + } + return equalASCIIFold(u.Host, r.Host) +} + +func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string { + if u.Subprotocols != nil { + clientProtocols := Subprotocols(r) + for _, serverProtocol := range u.Subprotocols { + for _, clientProtocol := range clientProtocols { + if clientProtocol == serverProtocol { + return clientProtocol + } + } + } + } else if responseHeader != nil { + return responseHeader.Get("Sec-Websocket-Protocol") + } + return "" +} + +// Upgrade upgrades the HTTP server connection to the WebSocket protocol. +// +// The responseHeader is included in the response to the client's upgrade +// request. Use the responseHeader to specify cookies (Set-Cookie) and the +// application negotiated subprotocol (Sec-WebSocket-Protocol). +// +// If the upgrade fails, then Upgrade replies to the client with an HTTP error +// response. +func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) { + const badHandshake = "websocket: the client is not using the websocket protocol: " + + if !tokenListContainsValue(r.Header, "Connection", "upgrade") { + return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'upgrade' token not found in 'Connection' header") + } + + if !tokenListContainsValue(r.Header, "Upgrade", "websocket") { + return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'websocket' token not found in 'Upgrade' header") + } + + if r.Method != "GET" { + return u.returnError(w, r, http.StatusMethodNotAllowed, badHandshake+"request method is not GET") + } + + if !tokenListContainsValue(r.Header, "Sec-Websocket-Version", "13") { + return u.returnError(w, r, http.StatusBadRequest, "websocket: unsupported version: 13 not found in 'Sec-Websocket-Version' header") + } + + if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok { + return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific 'Sec-WebSocket-Extensions' headers are unsupported") + } + + checkOrigin := u.CheckOrigin + if checkOrigin == nil { + checkOrigin = checkSameOrigin + } + if !checkOrigin(r) { + return u.returnError(w, r, http.StatusForbidden, "websocket: request origin not allowed by Upgrader.CheckOrigin") + } + + challengeKey := r.Header.Get("Sec-Websocket-Key") + if challengeKey == "" { + return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: `Sec-WebSocket-Key' header is missing or blank") + } + + subprotocol := u.selectSubprotocol(r, responseHeader) + + // Negotiate PMCE + var compress bool + if u.EnableCompression { + for _, ext := range parseExtensions(r.Header) { + if ext[""] != "permessage-deflate" { + continue + } + compress = true + break + } + } + + h, ok := w.(http.Hijacker) + if !ok { + return u.returnError(w, r, http.StatusInternalServerError, "websocket: response does not implement http.Hijacker") + } + var brw *bufio.ReadWriter + netConn, brw, err := h.Hijack() + if err != nil { + return u.returnError(w, r, http.StatusInternalServerError, err.Error()) + } + + if brw.Reader.Buffered() > 0 { + netConn.Close() + return nil, errors.New("websocket: client sent data before handshake is complete") + } + + var br *bufio.Reader + if u.ReadBufferSize == 0 && bufioReaderSize(netConn, brw.Reader) > 256 { + // Reuse hijacked buffered reader as connection reader. + br = brw.Reader + } + + buf := bufioWriterBuffer(netConn, brw.Writer) + + var writeBuf []byte + if u.WriteBufferPool == nil && u.WriteBufferSize == 0 && len(buf) >= maxFrameHeaderSize+256 { + // Reuse hijacked write buffer as connection buffer. + writeBuf = buf + } + + c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize, u.WriteBufferPool, br, writeBuf) + c.subprotocol = subprotocol + + if compress { + c.newCompressionWriter = compressNoContextTakeover + c.newDecompressionReader = decompressNoContextTakeover + } + + // Use larger of hijacked buffer and connection write buffer for header. + p := buf + if len(c.writeBuf) > len(p) { + p = c.writeBuf + } + p = p[:0] + + p = append(p, "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "...) + p = append(p, computeAcceptKey(challengeKey)...) + p = append(p, "\r\n"...) + if c.subprotocol != "" { + p = append(p, "Sec-WebSocket-Protocol: "...) + p = append(p, c.subprotocol...) + p = append(p, "\r\n"...) + } + if compress { + p = append(p, "Sec-WebSocket-Extensions: permessage-deflate; server_no_context_takeover; client_no_context_takeover\r\n"...) + } + for k, vs := range responseHeader { + if k == "Sec-Websocket-Protocol" { + continue + } + for _, v := range vs { + p = append(p, k...) + p = append(p, ": "...) + for i := 0; i < len(v); i++ { + b := v[i] + if b <= 31 { + // prevent response splitting. + b = ' ' + } + p = append(p, b) + } + p = append(p, "\r\n"...) + } + } + p = append(p, "\r\n"...) + + // Clear deadlines set by HTTP server. + netConn.SetDeadline(time.Time{}) + + if u.HandshakeTimeout > 0 { + netConn.SetWriteDeadline(time.Now().Add(u.HandshakeTimeout)) + } + if _, err = netConn.Write(p); err != nil { + netConn.Close() + return nil, err + } + if u.HandshakeTimeout > 0 { + netConn.SetWriteDeadline(time.Time{}) + } + + return c, nil +} + +// Upgrade upgrades the HTTP server connection to the WebSocket protocol. +// +// Deprecated: Use websocket.Upgrader instead. +// +// Upgrade does not perform origin checking. The application is responsible for +// checking the Origin header before calling Upgrade. An example implementation +// of the same origin policy check is: +// +// if req.Header.Get("Origin") != "http://"+req.Host { +// http.Error(w, "Origin not allowed", http.StatusForbidden) +// return +// } +// +// If the endpoint supports subprotocols, then the application is responsible +// for negotiating the protocol used on the connection. Use the Subprotocols() +// function to get the subprotocols requested by the client. Use the +// Sec-Websocket-Protocol response header to specify the subprotocol selected +// by the application. +// +// The responseHeader is included in the response to the client's upgrade +// request. Use the responseHeader to specify cookies (Set-Cookie) and the +// negotiated subprotocol (Sec-Websocket-Protocol). +// +// The connection buffers IO to the underlying network connection. The +// readBufSize and writeBufSize parameters specify the size of the buffers to +// use. Messages can be larger than the buffers. +// +// If the request is not a valid WebSocket handshake, then Upgrade returns an +// error of type HandshakeError. Applications should handle this error by +// replying to the client with an HTTP error response. +func Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header, readBufSize, writeBufSize int) (*Conn, error) { + u := Upgrader{ReadBufferSize: readBufSize, WriteBufferSize: writeBufSize} + u.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) { + // don't return errors to maintain backwards compatibility + } + u.CheckOrigin = func(r *http.Request) bool { + // allow all connections by default + return true + } + return u.Upgrade(w, r, responseHeader) +} + +// Subprotocols returns the subprotocols requested by the client in the +// Sec-Websocket-Protocol header. +func Subprotocols(r *http.Request) []string { + h := strings.TrimSpace(r.Header.Get("Sec-Websocket-Protocol")) + if h == "" { + return nil + } + protocols := strings.Split(h, ",") + for i := range protocols { + protocols[i] = strings.TrimSpace(protocols[i]) + } + return protocols +} + +// IsWebSocketUpgrade returns true if the client requested upgrade to the +// WebSocket protocol. +func IsWebSocketUpgrade(r *http.Request) bool { + return tokenListContainsValue(r.Header, "Connection", "upgrade") && + tokenListContainsValue(r.Header, "Upgrade", "websocket") +} + +// bufioReaderSize size returns the size of a bufio.Reader. +func bufioReaderSize(originalReader io.Reader, br *bufio.Reader) int { + // This code assumes that peek on a reset reader returns + // bufio.Reader.buf[:0]. + // TODO: Use bufio.Reader.Size() after Go 1.10 + br.Reset(originalReader) + if p, err := br.Peek(0); err == nil { + return cap(p) + } + return 0 +} + +// writeHook is an io.Writer that records the last slice passed to it vio +// io.Writer.Write. +type writeHook struct { + p []byte +} + +func (wh *writeHook) Write(p []byte) (int, error) { + wh.p = p + return len(p), nil +} + +// bufioWriterBuffer grabs the buffer from a bufio.Writer. +func bufioWriterBuffer(originalWriter io.Writer, bw *bufio.Writer) []byte { + // This code assumes that bufio.Writer.buf[:1] is passed to the + // bufio.Writer's underlying writer. + var wh writeHook + bw.Reset(&wh) + bw.WriteByte(0) + bw.Flush() + + bw.Reset(originalWriter) + + return wh.p[:cap(wh.p)] +} -- cgit v1.2.3-54-g00ecf