From 56e74239d6b34df8f30ef046f0b0ff4ff0866a71 Mon Sep 17 00:00:00 2001 From: =Corey Hulen Date: Sun, 14 Jun 2015 23:53:32 -0800 Subject: first commit --- .../src/github.com/gorilla/websocket/server.go | 247 +++++++++++++++++++++ 1 file changed, 247 insertions(+) create mode 100644 Godeps/_workspace/src/github.com/gorilla/websocket/server.go (limited to 'Godeps/_workspace/src/github.com/gorilla/websocket/server.go') diff --git a/Godeps/_workspace/src/github.com/gorilla/websocket/server.go b/Godeps/_workspace/src/github.com/gorilla/websocket/server.go new file mode 100644 index 000000000..e56a00493 --- /dev/null +++ b/Godeps/_workspace/src/github.com/gorilla/websocket/server.go @@ -0,0 +1,247 @@ +// 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" + "net" + "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 a default value of 4096 is used. The I/O buffer sizes + // do not limit the size of the messages that can be sent or received. + ReadBufferSize, WriteBufferSize int + + // Subprotocols specifies the server's supported protocols in order of + // preference. If this field is set, then the Upgrade method negotiates a + // subprotocol by selecting the first match in this list with a protocol + // requested by the client. + 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, the host in the Origin header must not be set or + // must match the host of the request. + CheckOrigin func(r *http.Request) 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 { + 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 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). +func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) { + if values := r.Header["Sec-Websocket-Version"]; len(values) == 0 || values[0] != "13" { + return u.returnError(w, r, http.StatusBadRequest, "websocket: version != 13") + } + + if !tokenListContainsValue(r.Header, "Connection", "upgrade") { + return u.returnError(w, r, http.StatusBadRequest, "websocket: could not find connection header with token 'upgrade'") + } + + if !tokenListContainsValue(r.Header, "Upgrade", "websocket") { + return u.returnError(w, r, http.StatusBadRequest, "websocket: could not find upgrade header with token 'websocket'") + } + + checkOrigin := u.CheckOrigin + if checkOrigin == nil { + checkOrigin = checkSameOrigin + } + if !checkOrigin(r) { + return u.returnError(w, r, http.StatusForbidden, "websocket: origin not allowed") + } + + challengeKey := r.Header.Get("Sec-Websocket-Key") + if challengeKey == "" { + return u.returnError(w, r, http.StatusBadRequest, "websocket: key missing or blank") + } + + subprotocol := u.selectSubprotocol(r, responseHeader) + + var ( + netConn net.Conn + br *bufio.Reader + err error + ) + + h, ok := w.(http.Hijacker) + if !ok { + return u.returnError(w, r, http.StatusInternalServerError, "websocket: response does not implement http.Hijacker") + } + var rw *bufio.ReadWriter + netConn, rw, err = h.Hijack() + if err != nil { + return u.returnError(w, r, http.StatusInternalServerError, err.Error()) + } + br = rw.Reader + + if br.Buffered() > 0 { + netConn.Close() + return nil, errors.New("websocket: client sent data before handshake is complete") + } + + c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize) + c.subprotocol = subprotocol + + p := c.writeBuf[: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"...) + } + 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. +// +// This function is deprecated, use websocket.Upgrader instead. +// +// The application is responsible for checking the request origin before +// calling Upgrade. An example implementation of the same origin policy is: +// +// if req.Header.Get("Origin") != "http://"+req.Host { +// http.Error(w, "Origin not allowed", 403) +// 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 +} -- cgit v1.2.3-1-g7c22