cloudflared/websocket/websocket_test.go
Benjamin Buzbee 452f8cef79
Allow partial reads from a GorillaConn; add SetDeadline (from net.Conn) (#330)
* Allow partial reads from a GorillaConn; add SetDeadline (from net.Conn)

The current implementation of GorillaConn will drop data if the
websocket frame isn't read 100%. For example, if a websocket frame is
size=3, and Read() is called with a []byte of len=1, the 2 other bytes
in the frame are lost forever.

This is currently masked by the fact that this is used primarily in
io.Copy to another socket (in ingress.Stream) - as long as the read buffer
used by io.Copy is big enough (it is 32*1024, so in theory we could see
this today?) then data is copied over to the other socket.

The client then can do partial reads just fine as the kernel will take
care of the buffer from here on out.

I hit this by trying to create my own tunnel and avoiding
ingress.Stream, but this could be a real bug today I think if a
websocket frame bigger than 32*1024 was received, although it is also
possible that we are lucky and the upstream size which I haven't checked
uses a smaller buffer than that always.

The test I added hangs before my change, succeeds after.

Also add SetDeadline so that GorillaConn fully implements net.Conn

* Comment formatting; fast path

* Avoid intermediate buffer for first len(p) bytes; import order
2021-03-09 19:57:04 +04:00

192 lines
5.4 KiB
Go

package websocket
import (
"context"
"crypto/tls"
"crypto/x509"
"fmt"
"io"
"math/rand"
"net/http"
"testing"
"time"
"github.com/rs/zerolog"
"github.com/cloudflare/cloudflared/hello"
"github.com/cloudflare/cloudflared/tlsconfig"
gws "github.com/gorilla/websocket"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"golang.org/x/net/websocket"
)
const (
// example in Sec-Websocket-Key in rfc6455
testSecWebsocketKey = "dGhlIHNhbXBsZSBub25jZQ=="
// example Sec-Websocket-Accept in rfc6455
testSecWebsocketAccept = "s3pPLMBiTxaQ9kYGzzhZRbK+xOo="
)
func testRequest(t *testing.T, url string, stream io.ReadWriter) *http.Request {
req, err := http.NewRequest("GET", url, stream)
if err != nil {
t.Fatalf("testRequestHeader error")
}
req.Header.Add("Connection", "Upgrade")
req.Header.Add("Upgrade", "WebSocket")
req.Header.Add("Sec-Websocket-Key", testSecWebsocketKey)
req.Header.Add("Sec-Websocket-Protocol", "tunnel-protocol")
req.Header.Add("Sec-Websocket-Version", "13")
req.Header.Add("User-Agent", "curl/7.59.0")
return req
}
func websocketClientTLSConfig(t *testing.T) *tls.Config {
certPool := x509.NewCertPool()
helloCert, err := tlsconfig.GetHelloCertificateX509()
assert.NoError(t, err)
certPool.AddCert(helloCert)
assert.NotNil(t, certPool)
return &tls.Config{RootCAs: certPool}
}
func TestWebsocketHeaders(t *testing.T) {
req := testRequest(t, "http://example.com", nil)
wsHeaders := websocketHeaders(req)
for _, header := range stripWebsocketHeaders {
assert.Empty(t, wsHeaders[header])
}
assert.Equal(t, "curl/7.59.0", wsHeaders.Get("User-Agent"))
}
func TestGenerateAcceptKey(t *testing.T) {
req := testRequest(t, "http://example.com", nil)
assert.Equal(t, testSecWebsocketAccept, generateAcceptKey(req))
}
func TestServe(t *testing.T) {
log := zerolog.Nop()
shutdownC := make(chan struct{})
errC := make(chan error)
listener, err := hello.CreateTLSListener("localhost:1111")
assert.NoError(t, err)
defer listener.Close()
go func() {
errC <- hello.StartHelloWorldServer(&log, listener, shutdownC)
}()
req := testRequest(t, "https://localhost:1111/ws", nil)
tlsConfig := websocketClientTLSConfig(t)
assert.NotNil(t, tlsConfig)
d := gws.Dialer{TLSClientConfig: tlsConfig}
conn, resp, err := ClientConnect(req, &d)
assert.NoError(t, err)
assert.Equal(t, testSecWebsocketAccept, resp.Header.Get("Sec-WebSocket-Accept"))
for i := 0; i < 1000; i++ {
messageSize := rand.Int()%2048 + 1
clientMessage := make([]byte, messageSize)
// rand.Read always returns len(clientMessage) and a nil error
rand.Read(clientMessage)
err = conn.WriteMessage(websocket.BinaryFrame, clientMessage)
assert.NoError(t, err)
messageType, message, err := conn.ReadMessage()
assert.NoError(t, err)
assert.Equal(t, websocket.BinaryFrame, messageType)
assert.Equal(t, clientMessage, message)
}
_ = conn.Close()
close(shutdownC)
<-errC
}
func TestWebsocketWrapper(t *testing.T) {
listener, err := hello.CreateTLSListener("localhost:0")
require.NoError(t, err)
serverErrorChan := make(chan error)
helloSvrCtx, cancelHelloSvr := context.WithCancel(context.Background())
defer func() { <-serverErrorChan }()
defer cancelHelloSvr()
go func() {
log := zerolog.Nop()
serverErrorChan <- hello.StartHelloWorldServer(&log, listener, helloSvrCtx.Done())
}()
tlsConfig := websocketClientTLSConfig(t)
d := gws.Dialer{TLSClientConfig: tlsConfig, HandshakeTimeout: time.Minute}
testAddr := fmt.Sprintf("https://%s/ws", listener.Addr().String())
req := testRequest(t, testAddr, nil)
conn, resp, err := ClientConnect(req, &d)
require.NoError(t, err)
require.Equal(t, testSecWebsocketAccept, resp.Header.Get("Sec-WebSocket-Accept"))
// Websocket now connected to test server so lets check our wrapper
wrapper := GorillaConn{Conn: conn}
buf := make([]byte, 100)
wrapper.Write([]byte("abc"))
n, err := wrapper.Read(buf)
require.NoError(t, err)
require.Equal(t, n, 3)
require.Equal(t, "abc", string(buf[:n]))
// Test partial read, read 1 of 3 bytes in one read and the other 2 in another read
wrapper.Write([]byte("abc"))
buf = buf[:1]
n, err = wrapper.Read(buf)
require.NoError(t, err)
require.Equal(t, n, 1)
require.Equal(t, "a", string(buf[:n]))
buf = buf[:cap(buf)]
n, err = wrapper.Read(buf)
require.NoError(t, err)
require.Equal(t, n, 2)
require.Equal(t, "bc", string(buf[:n]))
}
// func TestStartProxyServer(t *testing.T) {
// var wg sync.WaitGroup
// remoteAddress := "localhost:1113"
// listenerAddress := "localhost:1112"
// message := "Good morning Austin! Time for another sunny day in the great state of Texas."
// logger := zerolog.Nop()
// shutdownC := make(chan struct{})
// listener, err := net.Listen("tcp", listenerAddress)
// assert.NoError(t, err)
// defer listener.Close()
// remoteListener, err := net.Listen("tcp", remoteAddress)
// assert.NoError(t, err)
// defer remoteListener.Close()
// wg.Add(1)
// go func() {
// defer wg.Done()
// conn, err := remoteListener.Accept()
// assert.NoError(t, err)
// buf := make([]byte, len(message))
// conn.Read(buf)
// assert.Equal(t, string(buf), message)
// }()
// go func() {
// StartProxyServer(logger, listener, remoteAddress, shutdownC)
// }()
// req := testRequest(t, fmt.Sprintf("http://%s/", listenerAddress), nil)
// conn, _, err := ClientConnect(req, nil)
// assert.NoError(t, err)
// err = conn.WriteMessage(1, []byte(message))
// assert.NoError(t, err)
// wg.Wait()
// }