1 files changed, 219 insertions, 0 deletions
diff --git a/libgo/go/websocket/server.go b/libgo/go/websocket/server.go
new file mode 100644
index 000000000..dd797f24e
--- /dev/null
+++ b/libgo/go/websocket/server.go
@@ -0,0 +1,219 @@
+// Copyright 2009 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 websocket
+
+import (
+	"http"
+	"io"
+	"strings"
+)
+
+/*
+Handler is an interface to a WebSocket.
+
+A trivial example server:
+
+	package main
+
+	import (
+		"http"
+		"io"
+		"websocket"
+	)
+
+	// Echo the data received on the Web Socket.
+	func EchoServer(ws *websocket.Conn) {
+		io.Copy(ws, ws);
+	}
+
+	func main() {
+		http.Handle("/echo", websocket.Handler(EchoServer));
+		err := http.ListenAndServe(":12345", nil);
+		if err != nil {
+			panic("ListenAndServe: " + err.String())
+		}
+	}
+*/
+type Handler func(*Conn)
+
+/*
+Gets key number from Sec-WebSocket-Key<n>: field as described
+in 5.2 Sending the server's opening handshake, 4.
+*/
+func getKeyNumber(s string) (r uint32) {
+	// 4. Let /key-number_n/ be the digits (characters in the range
+	// U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9)) in /key_1/,
+	// interpreted as a base ten integer, ignoring all other characters
+	// in /key_n/.
+	r = 0
+	for i := 0; i < len(s); i++ {
+		if s[i] >= '0' && s[i] <= '9' {
+			r = r*10 + uint32(s[i]) - '0'
+		}
+	}
+	return
+}
+
+// ServeHTTP implements the http.Handler interface for a Web Socket
+func (f Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	rwc, buf, err := w.Hijack()
+	if err != nil {
+		panic("Hijack failed: " + err.String())
+		return
+	}
+	// The server should abort the WebSocket connection if it finds
+	// the client did not send a handshake that matches with protocol
+	// specification.
+	defer rwc.Close()
+
+	if req.Method != "GET" {
+		return
+	}
+	// HTTP version can be safely ignored.
+
+	if strings.ToLower(req.Header["Upgrade"]) != "websocket" ||
+		strings.ToLower(req.Header["Connection"]) != "upgrade" {
+		return
+	}
+
+	// TODO(ukai): check Host
+	origin, found := req.Header["Origin"]
+	if !found {
+		return
+	}
+
+	key1, found := req.Header["Sec-Websocket-Key1"]
+	if !found {
+		return
+	}
+	key2, found := req.Header["Sec-Websocket-Key2"]
+	if !found {
+		return
+	}
+	key3 := make([]byte, 8)
+	if _, err := io.ReadFull(buf, key3); err != nil {
+		return
+	}
+
+	var location string
+	if w.UsingTLS() {
+		location = "wss://" + req.Host + req.URL.RawPath
+	} else {
+		location = "ws://" + req.Host + req.URL.RawPath
+	}
+
+	// Step 4. get key number in Sec-WebSocket-Key<n> fields.
+	keyNumber1 := getKeyNumber(key1)
+	keyNumber2 := getKeyNumber(key2)
+
+	// Step 5. get number of spaces in Sec-WebSocket-Key<n> fields.
+	space1 := uint32(strings.Count(key1, " "))
+	space2 := uint32(strings.Count(key2, " "))
+	if space1 == 0 || space2 == 0 {
+		return
+	}
+
+	// Step 6. key number must be an integral multiple of spaces.
+	if keyNumber1%space1 != 0 || keyNumber2%space2 != 0 {
+		return
+	}
+
+	// Step 7. let part be key number divided by spaces.
+	part1 := keyNumber1 / space1
+	part2 := keyNumber2 / space2
+
+	// Step 8. let challenge to be concatination of part1, part2 and key3.
+	// Step 9. get MD5 fingerprint of challenge.
+	response, err := getChallengeResponse(part1, part2, key3)
+	if err != nil {
+		return
+	}
+
+	// Step 10. send response status line.
+	buf.WriteString("HTTP/1.1 101 WebSocket Protocol Handshake\r\n")
+	// Step 11. send response headers.
+	buf.WriteString("Upgrade: WebSocket\r\n")
+	buf.WriteString("Connection: Upgrade\r\n")
+	buf.WriteString("Sec-WebSocket-Location: " + location + "\r\n")
+	buf.WriteString("Sec-WebSocket-Origin: " + origin + "\r\n")
+	protocol, found := req.Header["Sec-Websocket-Protocol"]
+	if found {
+		buf.WriteString("Sec-WebSocket-Protocol: " + protocol + "\r\n")
+	}
+	// Step 12. send CRLF.
+	buf.WriteString("\r\n")
+	// Step 13. send response data.
+	buf.Write(response)
+	if err := buf.Flush(); err != nil {
+		return
+	}
+	ws := newConn(origin, location, protocol, buf, rwc)
+	f(ws)
+}
+
+
+/*
+Draft75Handler is an interface to a WebSocket based on the
+(soon obsolete) draft-hixie-thewebsocketprotocol-75.
+*/
+type Draft75Handler func(*Conn)
+
+// ServeHTTP implements the http.Handler interface for a Web Socket.
+func (f Draft75Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if req.Method != "GET" || req.Proto != "HTTP/1.1" {
+		w.WriteHeader(http.StatusBadRequest)
+		io.WriteString(w, "Unexpected request")
+		return
+	}
+	if req.Header["Upgrade"] != "WebSocket" {
+		w.WriteHeader(http.StatusBadRequest)
+		io.WriteString(w, "missing Upgrade: WebSocket header")
+		return
+	}
+	if req.Header["Connection"] != "Upgrade" {
+		w.WriteHeader(http.StatusBadRequest)
+		io.WriteString(w, "missing Connection: Upgrade header")
+		return
+	}
+	origin, found := req.Header["Origin"]
+	if !found {
+		w.WriteHeader(http.StatusBadRequest)
+		io.WriteString(w, "missing Origin header")
+		return
+	}
+
+	rwc, buf, err := w.Hijack()
+	if err != nil {
+		panic("Hijack failed: " + err.String())
+		return
+	}
+	defer rwc.Close()
+
+	var location string
+	if w.UsingTLS() {
+		location = "wss://" + req.Host + req.URL.RawPath
+	} else {
+		location = "ws://" + req.Host + req.URL.RawPath
+	}
+
+	// TODO(ukai): verify origin,location,protocol.
+
+	buf.WriteString("HTTP/1.1 101 Web Socket Protocol Handshake\r\n")
+	buf.WriteString("Upgrade: WebSocket\r\n")
+	buf.WriteString("Connection: Upgrade\r\n")
+	buf.WriteString("WebSocket-Origin: " + origin + "\r\n")
+	buf.WriteString("WebSocket-Location: " + location + "\r\n")
+	protocol, found := req.Header["Websocket-Protocol"]
+	// canonical header key of WebSocket-Protocol.
+	if found {
+		buf.WriteString("WebSocket-Protocol: " + protocol + "\r\n")
+	}
+	buf.WriteString("\r\n")
+	if err := buf.Flush(); err != nil {
+		return
+	}
+	ws := newConn(origin, location, protocol, buf, rwc)
+	f(ws)
+}