package splithttp import ( "bytes" "context" "fmt" "io" gonet "net" "net/http" "net/http/httptrace" "sync" "github.com/xtls/xray-core/common" "github.com/xtls/xray-core/common/errors" "github.com/xtls/xray-core/common/net" "github.com/xtls/xray-core/common/signal/done" ) // interface to abstract between use of browser dialer, vs net/http type DialerClient interface { // (ctx, baseURL, payload) -> err // baseURL already contains sessionId and seq SendUploadRequest(context.Context, string, io.ReadWriteCloser, int64) error // (ctx, baseURL) -> (downloadReader, remoteAddr, localAddr) // baseURL already contains sessionId OpenDownload(context.Context, string) (io.ReadCloser, net.Addr, net.Addr, error) } // implements splithttp.DialerClient in terms of direct network connections type DefaultDialerClient struct { transportConfig *Config download *http.Client upload *http.Client isH2 bool isH3 bool // pool of net.Conn, created using dialUploadConn uploadRawPool *sync.Pool dialUploadConn func(ctxInner context.Context) (net.Conn, error) } func (c *DefaultDialerClient) OpenDownload(ctx context.Context, baseURL string) (io.ReadCloser, gonet.Addr, gonet.Addr, error) { var remoteAddr gonet.Addr var localAddr gonet.Addr // this is done when the TCP/UDP connection to the server was established, // and we can unblock the Dial function and print correct net addresses in // logs gotConn := done.New() var downResponse io.ReadCloser gotDownResponse := done.New() ctx, ctxCancel := context.WithCancel(ctx) go func() { trace := &httptrace.ClientTrace{ GotConn: func(connInfo httptrace.GotConnInfo) { remoteAddr = connInfo.Conn.RemoteAddr() localAddr = connInfo.Conn.LocalAddr() gotConn.Close() }, } // in case we hit an error, we want to unblock this part defer gotConn.Close() ctx = httptrace.WithClientTrace(ctx, trace) req, err := http.NewRequestWithContext( ctx, "GET", baseURL, nil, ) if err != nil { errors.LogInfoInner(ctx, err, "failed to construct download http request") gotDownResponse.Close() return } req.Header = c.transportConfig.GetRequestHeader() response, err := c.download.Do(req) gotConn.Close() if err != nil { errors.LogInfoInner(ctx, err, "failed to send download http request") gotDownResponse.Close() return } if response.StatusCode != 200 { response.Body.Close() errors.LogInfo(ctx, "invalid status code on download:", response.Status) gotDownResponse.Close() return } downResponse = response.Body gotDownResponse.Close() }() if !c.isH3 { // in quic-go, sometimes gotConn is never closed for the lifetime of // the entire connection, and the download locks up // https://github.com/quic-go/quic-go/issues/3342 // for other HTTP versions, we want to block Dial until we know the // remote address of the server, for logging purposes <-gotConn.Wait() } lazyDownload := &LazyReader{ CreateReader: func() (io.Reader, error) { <-gotDownResponse.Wait() if downResponse == nil { return nil, errors.New("downResponse failed") } return downResponse, nil }, } // workaround for https://github.com/quic-go/quic-go/issues/2143 -- // always cancel request context so that Close cancels any Read. // Should then match the behavior of http2 and http1. reader := downloadBody{ lazyDownload, ctxCancel, } return reader, remoteAddr, localAddr, nil } func (c *DefaultDialerClient) SendUploadRequest(ctx context.Context, url string, payload io.ReadWriteCloser, contentLength int64) error { req, err := http.NewRequest("POST", url, payload) if err != nil { return err } req.ContentLength = contentLength req.Header = c.transportConfig.GetRequestHeader() if c.isH2 || c.isH3 { resp, err := c.upload.Do(req) if err != nil { return err } defer resp.Body.Close() if resp.StatusCode != 200 { return errors.New("bad status code:", resp.Status) } } else { // stringify the entire HTTP/1.1 request so it can be // safely retried. if instead req.Write is called multiple // times, the body is already drained after the first // request requestBuff := new(bytes.Buffer) common.Must(req.Write(requestBuff)) var uploadConn any var h1UploadConn *H1Conn for { uploadConn = c.uploadRawPool.Get() newConnection := uploadConn == nil if newConnection { newConn, err := c.dialUploadConn(context.WithoutCancel(ctx)) if err != nil { return err } h1UploadConn = NewH1Conn(newConn) uploadConn = h1UploadConn } else { h1UploadConn = uploadConn.(*H1Conn) // TODO: Replace 0 here with a config value later // Or add some other condition for optimization purposes if h1UploadConn.UnreadedResponsesCount > 0 { resp, err := http.ReadResponse(h1UploadConn.RespBufReader, req) if err != nil { return fmt.Errorf("error while reading response: %s", err.Error()) } if resp.StatusCode != 200 { return fmt.Errorf("got non-200 error response code: %d", resp.StatusCode) } } } _, err := h1UploadConn.Write(requestBuff.Bytes()) // if the write failed, we try another connection from // the pool, until the write on a new connection fails. // failed writes to a pooled connection are normal when // the connection has been closed in the meantime. if err == nil { break } else if newConnection { return err } } c.uploadRawPool.Put(uploadConn) } return nil } type downloadBody struct { io.Reader cancel context.CancelFunc } func (c downloadBody) Close() error { c.cancel() return nil }