websocket: correct challenge response

Tested against latest Chrome.

R=ukai, rsc
CC=golang-dev
https://golang.org/cl/1743053

src/pkg/websocket/client.go

@@ -5,11 +5,9 @@
 package websocket
 
 import (
-	"encoding/binary"
 	"bufio"
 	"bytes"
 	"container/vector"
-	"crypto/md5"
 	"fmt"
 	"http"
 	"io"
@@ -157,32 +155,6 @@ func generateKey3() (key []byte) {
 	return
 }
 
-/*
-Gets expected from challenge as described in 4.1 Opening handshake
-step 42 to 43.
-cf. http://www.whatwg.org/specs/web-socket-protocol/
-*/
-func getExpectedForChallenge(number1, number2 uint32, key3 []byte) (expected []byte, err os.Error) {
-	// 41. Let /challenge/ be the concatenation of /number_1/, expressed
-	// a big-endian 32 bit integer, /number_2/, expressed in a big-
-	// endian 32 bit integer, and the eight bytes of /key_3/ in the
-	// order they were sent to the wire.
-	challenge := make([]byte, 16)
-	challengeBuf := bytes.NewBuffer(challenge)
-	binary.Write(challengeBuf, binary.BigEndian, number1)
-	binary.Write(challengeBuf, binary.BigEndian, number2)
-	copy(challenge[8:], key3)
-
-	// 42. Let /expected/ be the MD5 fingerprint of /challenge/ as a big-
-	// endian 128 bit string.
-	h := md5.New()
-	if _, err = h.Write(challenge); err != nil {
-		return
-	}
-	expected = h.Sum()
-	return
-}
-
 /*
 Web Socket protocol handshake based on
 http://www.whatwg.org/specs/web-socket-protocol/
@@ -258,7 +230,7 @@ func handshake(resourceName, host, origin, location, protocol string, br *bufio.
 	}
 
 	// Step 42-43. get expected data from challange data.
-	expected, err := getExpectedForChallenge(number1, number2, key3)
+	expected, err := getChallengeResponse(number1, number2, key3)
 	if err != nil {
 		return err
 	}