TUN-8052: Update go to 1.21.5

Also update golang.org/x/net and google.golang.org/grpc to fix vulnerabilities,
although cloudflared is using them in a way that is not exposed to those risks

vendor/google.golang.org/grpc/internal/transport/controlbuf.go

@@ -22,6 +22,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"net"
 	"runtime"
 	"strconv"
 	"sync"
@@ -29,6 +30,7 @@ import (
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	"google.golang.org/grpc/internal/grpclog"
 	"google.golang.org/grpc/internal/grpcutil"
 	"google.golang.org/grpc/status"
 )
@@ -38,7 +40,7 @@ var updateHeaderTblSize = func(e *hpack.Encoder, v uint32) {
 }
 
 type itemNode struct {
-	it   interface{}
+	it   any
 	next *itemNode
 }
 
@@ -47,7 +49,7 @@ type itemList struct {
 	tail *itemNode
 }
 
-func (il *itemList) enqueue(i interface{}) {
+func (il *itemList) enqueue(i any) {
 	n := &itemNode{it: i}
 	if il.tail == nil {
 		il.head, il.tail = n, n
@@ -59,11 +61,11 @@ func (il *itemList) enqueue(i interface{}) {
 
 // peek returns the first item in the list without removing it from the
 // list.
-func (il *itemList) peek() interface{} {
+func (il *itemList) peek() any {
 	return il.head.it
 }
 
-func (il *itemList) dequeue() interface{} {
+func (il *itemList) dequeue() any {
 	if il.head == nil {
 		return nil
 	}
@@ -191,7 +193,7 @@ type goAway struct {
 	code      http2.ErrCode
 	debugData []byte
 	headsUp   bool
-	closeConn bool
+	closeConn error // if set, loopyWriter will exit, resulting in conn closure
 }
 
 func (*goAway) isTransportResponseFrame() bool { return false }
@@ -209,6 +211,14 @@ type outFlowControlSizeRequest struct {
 
 func (*outFlowControlSizeRequest) isTransportResponseFrame() bool { return false }
 
+// closeConnection is an instruction to tell the loopy writer to flush the
+// framer and exit, which will cause the transport's connection to be closed
+// (by the client or server).  The transport itself will close after the reader
+// encounters the EOF caused by the connection closure.
+type closeConnection struct{}
+
+func (closeConnection) isTransportResponseFrame() bool { return false }
+
 type outStreamState int
 
 const (
@@ -326,7 +336,7 @@ func (c *controlBuffer) put(it cbItem) error {
 	return err
 }
 
-func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it cbItem) (bool, error) {
+func (c *controlBuffer) executeAndPut(f func(it any) bool, it cbItem) (bool, error) {
 	var wakeUp bool
 	c.mu.Lock()
 	if c.err != nil {
@@ -363,7 +373,7 @@ func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it cbItem) (b
 }
 
 // Note argument f should never be nil.
-func (c *controlBuffer) execute(f func(it interface{}) bool, it interface{}) (bool, error) {
+func (c *controlBuffer) execute(f func(it any) bool, it any) (bool, error) {
 	c.mu.Lock()
 	if c.err != nil {
 		c.mu.Unlock()
@@ -377,7 +387,7 @@ func (c *controlBuffer) execute(f func(it interface{}) bool, it interface{}) (bo
 	return true, nil
 }
 
-func (c *controlBuffer) get(block bool) (interface{}, error) {
+func (c *controlBuffer) get(block bool) (any, error) {
 	for {
 		c.mu.Lock()
 		if c.err != nil {
@@ -408,7 +418,7 @@ func (c *controlBuffer) get(block bool) (interface{}, error) {
 		select {
 		case <-c.ch:
 		case <-c.done:
-			return nil, ErrConnClosing
+			return nil, errors.New("transport closed by client")
 		}
 	}
 }
@@ -478,12 +488,14 @@ type loopyWriter struct {
 	hEnc          *hpack.Encoder // HPACK encoder.
 	bdpEst        *bdpEstimator
 	draining      bool
+	conn          net.Conn
+	logger        *grpclog.PrefixLogger
 
 	// Side-specific handlers
 	ssGoAwayHandler func(*goAway) (bool, error)
 }
 
-func newLoopyWriter(s side, fr *framer, cbuf *controlBuffer, bdpEst *bdpEstimator) *loopyWriter {
+func newLoopyWriter(s side, fr *framer, cbuf *controlBuffer, bdpEst *bdpEstimator, conn net.Conn, logger *grpclog.PrefixLogger) *loopyWriter {
 	var buf bytes.Buffer
 	l := &loopyWriter{
 		side:          s,
@@ -496,6 +508,8 @@ func newLoopyWriter(s side, fr *framer, cbuf *controlBuffer, bdpEst *bdpEstimato
 		hBuf:          &buf,
 		hEnc:          hpack.NewEncoder(&buf),
 		bdpEst:        bdpEst,
+		conn:          conn,
+		logger:        logger,
 	}
 	return l
 }
@@ -513,23 +527,26 @@ const minBatchSize = 1000
 // 2. Stream level flow control quota available.
 //
 // In each iteration of run loop, other than processing the incoming control
-// frame, loopy calls processData, which processes one node from the activeStreams linked-list.
-// This results in writing of HTTP2 frames into an underlying write buffer.
-// When there's no more control frames to read from controlBuf, loopy flushes the write buffer.
-// As an optimization, to increase the batch size for each flush, loopy yields the processor, once
-// if the batch size is too low to give stream goroutines a chance to fill it up.
+// frame, loopy calls processData, which processes one node from the
+// activeStreams linked-list.  This results in writing of HTTP2 frames into an
+// underlying write buffer.  When there's no more control frames to read from
+// controlBuf, loopy flushes the write buffer.  As an optimization, to increase
+// the batch size for each flush, loopy yields the processor, once if the batch
+// size is too low to give stream goroutines a chance to fill it up.
+//
+// Upon exiting, if the error causing the exit is not an I/O error, run()
+// flushes and closes the underlying connection.  Otherwise, the connection is
+// left open to allow the I/O error to be encountered by the reader instead.
 func (l *loopyWriter) run() (err error) {
 	defer func() {
-		if err == ErrConnClosing {
-			// Don't log ErrConnClosing as error since it happens
-			// 1. When the connection is closed by some other known issue.
-			// 2. User closed the connection.
-			// 3. A graceful close of connection.
-			if logger.V(logLevel) {
-				logger.Infof("transport: loopyWriter.run returning. %v", err)
-			}
-			err = nil
+		if l.logger.V(logLevel) {
+			l.logger.Infof("loopyWriter exiting with error: %v", err)
 		}
+		if !isIOError(err) {
+			l.framer.writer.Flush()
+			l.conn.Close()
+		}
+		l.cbuf.finish()
 	}()
 	for {
 		it, err := l.cbuf.get(true)
@@ -574,7 +591,6 @@ func (l *loopyWriter) run() (err error) {
 			}
 			l.framer.writer.Flush()
 			break hasdata
-
 		}
 	}
 }
@@ -583,11 +599,11 @@ func (l *loopyWriter) outgoingWindowUpdateHandler(w *outgoingWindowUpdate) error
 	return l.framer.fr.WriteWindowUpdate(w.streamID, w.increment)
 }
 
-func (l *loopyWriter) incomingWindowUpdateHandler(w *incomingWindowUpdate) error {
+func (l *loopyWriter) incomingWindowUpdateHandler(w *incomingWindowUpdate) {
 	// Otherwise update the quota.
 	if w.streamID == 0 {
 		l.sendQuota += w.increment
-		return nil
+		return
 	}
 	// Find the stream and update it.
 	if str, ok := l.estdStreams[w.streamID]; ok {
@@ -595,10 +611,9 @@ func (l *loopyWriter) incomingWindowUpdateHandler(w *incomingWindowUpdate) error
 		if strQuota := int(l.oiws) - str.bytesOutStanding; strQuota > 0 && str.state == waitingOnStreamQuota {
 			str.state = active
 			l.activeStreams.enqueue(str)
-			return nil
+			return
 		}
 	}
-	return nil
 }
 
 func (l *loopyWriter) outgoingSettingsHandler(s *outgoingSettings) error {
@@ -606,13 +621,11 @@ func (l *loopyWriter) outgoingSettingsHandler(s *outgoingSettings) error {
 }
 
 func (l *loopyWriter) incomingSettingsHandler(s *incomingSettings) error {
-	if err := l.applySettings(s.ss); err != nil {
-		return err
-	}
+	l.applySettings(s.ss)
 	return l.framer.fr.WriteSettingsAck()
 }
 
-func (l *loopyWriter) registerStreamHandler(h *registerStream) error {
+func (l *loopyWriter) registerStreamHandler(h *registerStream) {
 	str := &outStream{
 		id:    h.streamID,
 		state: empty,
@@ -620,15 +633,14 @@ func (l *loopyWriter) registerStreamHandler(h *registerStream) error {
 		wq:    h.wq,
 	}
 	l.estdStreams[h.streamID] = str
-	return nil
 }
 
 func (l *loopyWriter) headerHandler(h *headerFrame) error {
 	if l.side == serverSide {
 		str, ok := l.estdStreams[h.streamID]
 		if !ok {
-			if logger.V(logLevel) {
-				logger.Warningf("transport: loopy doesn't recognize the stream: %d", h.streamID)
+			if l.logger.V(logLevel) {
+				l.logger.Infof("Unrecognized streamID %d in loopyWriter", h.streamID)
 			}
 			return nil
 		}
@@ -655,19 +667,20 @@ func (l *loopyWriter) headerHandler(h *headerFrame) error {
 		itl:   &itemList{},
 		wq:    h.wq,
 	}
-	str.itl.enqueue(h)
-	return l.originateStream(str)
+	return l.originateStream(str, h)
 }
 
-func (l *loopyWriter) originateStream(str *outStream) error {
-	hdr := str.itl.dequeue().(*headerFrame)
-	if err := hdr.initStream(str.id); err != nil {
-		if err == ErrConnClosing {
-			return err
-		}
-		// Other errors(errStreamDrain) need not close transport.
+func (l *loopyWriter) originateStream(str *outStream, hdr *headerFrame) error {
+	// l.draining is set when handling GoAway. In which case, we want to avoid
+	// creating new streams.
+	if l.draining {
+		// TODO: provide a better error with the reason we are in draining.
+		hdr.onOrphaned(errStreamDrain)
 		return nil
 	}
+	if err := hdr.initStream(str.id); err != nil {
+		return err
+	}
 	if err := l.writeHeader(str.id, hdr.endStream, hdr.hf, hdr.onWrite); err != nil {
 		return err
 	}
@@ -682,8 +695,8 @@ func (l *loopyWriter) writeHeader(streamID uint32, endStream bool, hf []hpack.He
 	l.hBuf.Reset()
 	for _, f := range hf {
 		if err := l.hEnc.WriteField(f); err != nil {
-			if logger.V(logLevel) {
-				logger.Warningf("transport: loopyWriter.writeHeader encountered error while encoding headers: %v", err)
+			if l.logger.V(logLevel) {
+				l.logger.Warningf("Encountered error while encoding headers: %v", err)
 			}
 		}
 	}
@@ -721,10 +734,10 @@ func (l *loopyWriter) writeHeader(streamID uint32, endStream bool, hf []hpack.He
 	return nil
 }
 
-func (l *loopyWriter) preprocessData(df *dataFrame) error {
+func (l *loopyWriter) preprocessData(df *dataFrame) {
 	str, ok := l.estdStreams[df.streamID]
 	if !ok {
-		return nil
+		return
 	}
 	// If we got data for a stream it means that
 	// stream was originated and the headers were sent out.
@@ -733,7 +746,6 @@ func (l *loopyWriter) preprocessData(df *dataFrame) error {
 		str.state = active
 		l.activeStreams.enqueue(str)
 	}
-	return nil
 }
 
 func (l *loopyWriter) pingHandler(p *ping) error {
@@ -744,9 +756,8 @@ func (l *loopyWriter) pingHandler(p *ping) error {
 
 }
 
-func (l *loopyWriter) outFlowControlSizeRequestHandler(o *outFlowControlSizeRequest) error {
+func (l *loopyWriter) outFlowControlSizeRequestHandler(o *outFlowControlSizeRequest) {
 	o.resp <- l.sendQuota
-	return nil
 }
 
 func (l *loopyWriter) cleanupStreamHandler(c *cleanupStream) error {
@@ -763,8 +774,9 @@ func (l *loopyWriter) cleanupStreamHandler(c *cleanupStream) error {
 			return err
 		}
 	}
-	if l.side == clientSide && l.draining && len(l.estdStreams) == 0 {
-		return ErrConnClosing
+	if l.draining && len(l.estdStreams) == 0 {
+		// Flush and close the connection; we are done with it.
+		return errors.New("finished processing active streams while in draining mode")
 	}
 	return nil
 }
@@ -799,7 +811,8 @@ func (l *loopyWriter) incomingGoAwayHandler(*incomingGoAway) error {
 	if l.side == clientSide {
 		l.draining = true
 		if len(l.estdStreams) == 0 {
-			return ErrConnClosing
+			// Flush and close the connection; we are done with it.
+			return errors.New("received GOAWAY with no active streams")
 		}
 	}
 	return nil
@@ -817,10 +830,10 @@ func (l *loopyWriter) goAwayHandler(g *goAway) error {
 	return nil
 }
 
-func (l *loopyWriter) handle(i interface{}) error {
+func (l *loopyWriter) handle(i any) error {
 	switch i := i.(type) {
 	case *incomingWindowUpdate:
-		return l.incomingWindowUpdateHandler(i)
+		l.incomingWindowUpdateHandler(i)
 	case *outgoingWindowUpdate:
 		return l.outgoingWindowUpdateHandler(i)
 	case *incomingSettings:
@@ -830,7 +843,7 @@ func (l *loopyWriter) handle(i interface{}) error {
 	case *headerFrame:
 		return l.headerHandler(i)
 	case *registerStream:
-		return l.registerStreamHandler(i)
+		l.registerStreamHandler(i)
 	case *cleanupStream:
 		return l.cleanupStreamHandler(i)
 	case *earlyAbortStream:
@@ -838,19 +851,24 @@ func (l *loopyWriter) handle(i interface{}) error {
 	case *incomingGoAway:
 		return l.incomingGoAwayHandler(i)
 	case *dataFrame:
-		return l.preprocessData(i)
+		l.preprocessData(i)
 	case *ping:
 		return l.pingHandler(i)
 	case *goAway:
 		return l.goAwayHandler(i)
 	case *outFlowControlSizeRequest:
-		return l.outFlowControlSizeRequestHandler(i)
+		l.outFlowControlSizeRequestHandler(i)
+	case closeConnection:
+		// Just return a non-I/O error and run() will flush and close the
+		// connection.
+		return ErrConnClosing
 	default:
 		return fmt.Errorf("transport: unknown control message type %T", i)
 	}
+	return nil
 }
 
-func (l *loopyWriter) applySettings(ss []http2.Setting) error {
+func (l *loopyWriter) applySettings(ss []http2.Setting) {
 	for _, s := range ss {
 		switch s.ID {
 		case http2.SettingInitialWindowSize:
@@ -869,7 +887,6 @@ func (l *loopyWriter) applySettings(ss []http2.Setting) error {
 			updateHeaderTblSize(l.hEnc, s.Val)
 		}
 	}
-	return nil
 }
 
 // processData removes the first stream from active streams, writes out at most 16KB
@@ -903,7 +920,7 @@ func (l *loopyWriter) processData() (bool, error) {
 				return false, err
 			}
 			if err := l.cleanupStreamHandler(trailer.cleanup); err != nil {
-				return false, nil
+				return false, err
 			}
 		} else {
 			l.activeStreams.enqueue(str)

vendor/google.golang.org/grpc/internal/transport/defaults.go

@@ -47,3 +47,9 @@ const (
 	defaultClientMaxHeaderListSize = uint32(16 << 20)
 	defaultServerMaxHeaderListSize = uint32(16 << 20)
 )
+
+// MaxStreamID is the upper bound for the stream ID before the current
+// transport gracefully closes and new transport is created for subsequent RPCs.
+// This is set to 75% of 2^31-1. Streams are identified with an unsigned 31-bit
+// integer. It's exported so that tests can override it.
+var MaxStreamID = uint32(math.MaxInt32 * 3 / 4)

vendor/google.golang.org/grpc/internal/transport/handler_server.go

@@ -39,6 +39,7 @@ import (
 	"golang.org/x/net/http2"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal/grpclog"
 	"google.golang.org/grpc/internal/grpcutil"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
@@ -46,40 +47,65 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// NewServerHandlerTransport returns a ServerTransport handling gRPC
-// from inside an http.Handler. It requires that the http Server
-// supports HTTP/2.
+// NewServerHandlerTransport returns a ServerTransport handling gRPC from
+// inside an http.Handler, or writes an HTTP error to w and returns an error.
+// It requires that the http Server supports HTTP/2.
 func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats []stats.Handler) (ServerTransport, error) {
 	if r.ProtoMajor != 2 {
-		return nil, errors.New("gRPC requires HTTP/2")
+		msg := "gRPC requires HTTP/2"
+		http.Error(w, msg, http.StatusBadRequest)
+		return nil, errors.New(msg)
 	}
 	if r.Method != "POST" {
-		return nil, errors.New("invalid gRPC request method")
+		msg := fmt.Sprintf("invalid gRPC request method %q", r.Method)
+		http.Error(w, msg, http.StatusBadRequest)
+		return nil, errors.New(msg)
 	}
 	contentType := r.Header.Get("Content-Type")
 	// TODO: do we assume contentType is lowercase? we did before
 	contentSubtype, validContentType := grpcutil.ContentSubtype(contentType)
 	if !validContentType {
-		return nil, errors.New("invalid gRPC request content-type")
+		msg := fmt.Sprintf("invalid gRPC request content-type %q", contentType)
+		http.Error(w, msg, http.StatusUnsupportedMediaType)
+		return nil, errors.New(msg)
 	}
 	if _, ok := w.(http.Flusher); !ok {
-		return nil, errors.New("gRPC requires a ResponseWriter supporting http.Flusher")
+		msg := "gRPC requires a ResponseWriter supporting http.Flusher"
+		http.Error(w, msg, http.StatusInternalServerError)
+		return nil, errors.New(msg)
 	}
 
+	var localAddr net.Addr
+	if la := r.Context().Value(http.LocalAddrContextKey); la != nil {
+		localAddr, _ = la.(net.Addr)
+	}
+	var authInfo credentials.AuthInfo
+	if r.TLS != nil {
+		authInfo = credentials.TLSInfo{State: *r.TLS, CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.PrivacyAndIntegrity}}
+	}
+	p := peer.Peer{
+		Addr:      strAddr(r.RemoteAddr),
+		LocalAddr: localAddr,
+		AuthInfo:  authInfo,
+	}
 	st := &serverHandlerTransport{
 		rw:             w,
 		req:            r,
 		closedCh:       make(chan struct{}),
 		writes:         make(chan func()),
+		peer:           p,
 		contentType:    contentType,
 		contentSubtype: contentSubtype,
 		stats:          stats,
 	}
+	st.logger = prefixLoggerForServerHandlerTransport(st)
 
 	if v := r.Header.Get("grpc-timeout"); v != "" {
 		to, err := decodeTimeout(v)
 		if err != nil {
-			return nil, status.Errorf(codes.Internal, "malformed time-out: %v", err)
+			msg := fmt.Sprintf("malformed grpc-timeout: %v", err)
+			http.Error(w, msg, http.StatusBadRequest)
+			return nil, status.Error(codes.Internal, msg)
 		}
 		st.timeoutSet = true
 		st.timeout = to
@@ -97,7 +123,9 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats []s
 		for _, v := range vv {
 			v, err := decodeMetadataHeader(k, v)
 			if err != nil {
-				return nil, status.Errorf(codes.Internal, "malformed binary metadata: %v", err)
+				msg := fmt.Sprintf("malformed binary metadata %q in header %q: %v", v, k, err)
+				http.Error(w, msg, http.StatusBadRequest)
+				return nil, status.Error(codes.Internal, msg)
 			}
 			metakv = append(metakv, k, v)
 		}
@@ -120,6 +148,8 @@ type serverHandlerTransport struct {
 
 	headerMD metadata.MD
 
+	peer peer.Peer
+
 	closeOnce sync.Once
 	closedCh  chan struct{} // closed on Close
 
@@ -138,16 +168,26 @@ type serverHandlerTransport struct {
 	// TODO make sure this is consistent across handler_server and http2_server
 	contentSubtype string
 
-	stats []stats.Handler
+	stats  []stats.Handler
+	logger *grpclog.PrefixLogger
 }
 
-func (ht *serverHandlerTransport) Close() {
-	ht.closeOnce.Do(ht.closeCloseChanOnce)
+func (ht *serverHandlerTransport) Close(err error) {
+	ht.closeOnce.Do(func() {
+		if ht.logger.V(logLevel) {
+			ht.logger.Infof("Closing: %v", err)
+		}
+		close(ht.closedCh)
+	})
 }
 
-func (ht *serverHandlerTransport) closeCloseChanOnce() { close(ht.closedCh) }
-
-func (ht *serverHandlerTransport) RemoteAddr() net.Addr { return strAddr(ht.req.RemoteAddr) }
+func (ht *serverHandlerTransport) Peer() *peer.Peer {
+	return &peer.Peer{
+		Addr:      ht.peer.Addr,
+		LocalAddr: ht.peer.LocalAddr,
+		AuthInfo:  ht.peer.AuthInfo,
+	}
+}
 
 // strAddr is a net.Addr backed by either a TCP "ip:port" string, or
 // the empty string if unknown.
@@ -202,18 +242,20 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 			h.Set("Grpc-Message", encodeGrpcMessage(m))
 		}
 
+		s.hdrMu.Lock()
 		if p := st.Proto(); p != nil && len(p.Details) > 0 {
+			delete(s.trailer, grpcStatusDetailsBinHeader)
 			stBytes, err := proto.Marshal(p)
 			if err != nil {
 				// TODO: return error instead, when callers are able to handle it.
 				panic(err)
 			}
 
-			h.Set("Grpc-Status-Details-Bin", encodeBinHeader(stBytes))
+			h.Set(grpcStatusDetailsBinHeader, encodeBinHeader(stBytes))
 		}
 
-		if md := s.Trailer(); len(md) > 0 {
-			for k, vv := range md {
+		if len(s.trailer) > 0 {
+			for k, vv := range s.trailer {
 				// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
 				if isReservedHeader(k) {
 					continue
@@ -225,6 +267,7 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 				}
 			}
 		}
+		s.hdrMu.Unlock()
 	})
 
 	if err == nil { // transport has not been closed
@@ -236,7 +279,7 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 			})
 		}
 	}
-	ht.Close()
+	ht.Close(errors.New("finished writing status"))
 	return err
 }
 
@@ -269,7 +312,7 @@ func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
 }
 
 // writeCustomHeaders sets custom headers set on the stream via SetHeader
-// on the first write call (Write, WriteHeader, or WriteStatus).
+// on the first write call (Write, WriteHeader, or WriteStatus)
 func (ht *serverHandlerTransport) writeCustomHeaders(s *Stream) {
 	h := ht.rw.Header()
 
@@ -326,10 +369,8 @@ func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
 	return err
 }
 
-func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), traceCtx func(context.Context, string) context.Context) {
+func (ht *serverHandlerTransport) HandleStreams(ctx context.Context, startStream func(*Stream)) {
 	// With this transport type there will be exactly 1 stream: this HTTP request.
-
-	ctx := ht.req.Context()
 	var cancel context.CancelFunc
 	if ht.timeoutSet {
 		ctx, cancel = context.WithTimeout(ctx, ht.timeout)
@@ -346,37 +387,22 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		case <-ht.req.Context().Done():
 		}
 		cancel()
-		ht.Close()
+		ht.Close(errors.New("request is done processing"))
 	}()
 
-	req := ht.req
-
-	s := &Stream{
-		id:             0, // irrelevant
-		requestRead:    func(int) {},
-		cancel:         cancel,
-		buf:            newRecvBuffer(),
-		st:             ht,
-		method:         req.URL.Path,
-		recvCompress:   req.Header.Get("grpc-encoding"),
-		contentSubtype: ht.contentSubtype,
-	}
-	pr := &peer.Peer{
-		Addr: ht.RemoteAddr(),
-	}
-	if req.TLS != nil {
-		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS, CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.PrivacyAndIntegrity}}
-	}
 	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
-	s.ctx = peer.NewContext(ctx, pr)
-	for _, sh := range ht.stats {
-		s.ctx = sh.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
-		inHeader := &stats.InHeader{
-			FullMethod:  s.method,
-			RemoteAddr:  ht.RemoteAddr(),
-			Compression: s.recvCompress,
-		}
-		sh.HandleRPC(s.ctx, inHeader)
+	req := ht.req
+	s := &Stream{
+		id:               0, // irrelevant
+		ctx:              ctx,
+		requestRead:      func(int) {},
+		cancel:           cancel,
+		buf:              newRecvBuffer(),
+		st:               ht,
+		method:           req.URL.Path,
+		recvCompress:     req.Header.Get("grpc-encoding"),
+		contentSubtype:   ht.contentSubtype,
+		headerWireLength: 0, // won't have access to header wire length until golang/go#18997.
 	}
 	s.trReader = &transportReader{
 		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf, freeBuffer: func(*bytes.Buffer) {}},
@@ -435,7 +461,7 @@ func (ht *serverHandlerTransport) IncrMsgSent() {}
 
 func (ht *serverHandlerTransport) IncrMsgRecv() {}
 
-func (ht *serverHandlerTransport) Drain() {
+func (ht *serverHandlerTransport) Drain(debugData string) {
 	panic("Drain() is not implemented")
 }
 

vendor/google.golang.org/grpc/internal/transport/http2_client.go

@@ -36,13 +36,15 @@ import (
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/channelz"
 	icredentials "google.golang.org/grpc/internal/credentials"
+	"google.golang.org/grpc/internal/grpclog"
 	"google.golang.org/grpc/internal/grpcsync"
 	"google.golang.org/grpc/internal/grpcutil"
 	imetadata "google.golang.org/grpc/internal/metadata"
 	istatus "google.golang.org/grpc/internal/status"
-	"google.golang.org/grpc/internal/syscall"
+	isyscall "google.golang.org/grpc/internal/syscall"
 	"google.golang.org/grpc/internal/transport/networktype"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
@@ -59,11 +61,15 @@ var clientConnectionCounter uint64
 
 // http2Client implements the ClientTransport interface with HTTP2.
 type http2Client struct {
-	lastRead   int64 // Keep this field 64-bit aligned. Accessed atomically.
-	ctx        context.Context
-	cancel     context.CancelFunc
-	ctxDone    <-chan struct{} // Cache the ctx.Done() chan.
-	userAgent  string
+	lastRead  int64 // Keep this field 64-bit aligned. Accessed atomically.
+	ctx       context.Context
+	cancel    context.CancelFunc
+	ctxDone   <-chan struct{} // Cache the ctx.Done() chan.
+	userAgent string
+	// address contains the resolver returned address for this transport.
+	// If the `ServerName` field is set, it takes precedence over `CallHdr.Host`
+	// passed to `NewStream`, when determining the :authority header.
+	address    resolver.Address
 	md         metadata.MD
 	conn       net.Conn // underlying communication channel
 	loopy      *loopyWriter
@@ -136,12 +142,12 @@ type http2Client struct {
 	channelzID *channelz.Identifier
 	czData     *channelzData
 
-	onGoAway func(GoAwayReason)
-	onClose  func()
+	onClose func(GoAwayReason)
 
 	bufferPool *bufferPool
 
 	connectionID uint64
+	logger       *grpclog.PrefixLogger
 }
 
 func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr resolver.Address, useProxy bool, grpcUA string) (net.Conn, error) {
@@ -171,7 +177,7 @@ func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error
 	if networkType == "tcp" && useProxy {
 		return proxyDial(ctx, address, grpcUA)
 	}
-	return (&net.Dialer{}).DialContext(ctx, networkType, address)
+	return internal.NetDialerWithTCPKeepalive().DialContext(ctx, networkType, address)
 }
 
 func isTemporary(err error) bool {
@@ -193,7 +199,7 @@ func isTemporary(err error) bool {
 // newHTTP2Client constructs a connected ClientTransport to addr based on HTTP2
 // and starts to receive messages on it. Non-nil error returns if construction
 // fails.
-func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onGoAway func(GoAwayReason), onClose func()) (_ *http2Client, err error) {
+func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onClose func(GoAwayReason)) (_ *http2Client, err error) {
 	scheme := "http"
 	ctx, cancel := context.WithCancel(ctx)
 	defer func() {
@@ -213,7 +219,7 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		if opts.FailOnNonTempDialError {
 			return nil, connectionErrorf(isTemporary(err), err, "transport: error while dialing: %v", err)
 		}
-		return nil, connectionErrorf(true, err, "transport: Error while dialing %v", err)
+		return nil, connectionErrorf(true, err, "transport: Error while dialing: %v", err)
 	}
 
 	// Any further errors will close the underlying connection
@@ -238,8 +244,11 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 	go func(conn net.Conn) {
 		defer ctxMonitorDone.Fire() // Signal this goroutine has exited.
 		<-newClientCtx.Done()       // Block until connectCtx expires or the defer above executes.
-		if connectCtx.Err() != nil {
+		if err := connectCtx.Err(); err != nil {
 			// connectCtx expired before exiting the function.  Hard close the connection.
+			if logger.V(logLevel) {
+				logger.Infof("Aborting due to connect deadline expiring: %v", err)
+			}
 			conn.Close()
 		}
 	}(conn)
@@ -254,7 +263,7 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 	}
 	keepaliveEnabled := false
 	if kp.Time != infinity {
-		if err = syscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil {
+		if err = isyscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil {
 			return nil, connectionErrorf(false, err, "transport: failed to set TCP_USER_TIMEOUT: %v", err)
 		}
 		keepaliveEnabled = true
@@ -314,6 +323,7 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		cancel:                cancel,
 		userAgent:             opts.UserAgent,
 		registeredCompressors: grpcutil.RegisteredCompressors(),
+		address:               addr,
 		conn:                  conn,
 		remoteAddr:            conn.RemoteAddr(),
 		localAddr:             conn.LocalAddr(),
@@ -321,7 +331,7 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		readerDone:            make(chan struct{}),
 		writerDone:            make(chan struct{}),
 		goAway:                make(chan struct{}),
-		framer:                newFramer(conn, writeBufSize, readBufSize, maxHeaderListSize),
+		framer:                newFramer(conn, writeBufSize, readBufSize, opts.SharedWriteBuffer, maxHeaderListSize),
 		fc:                    &trInFlow{limit: uint32(icwz)},
 		scheme:                scheme,
 		activeStreams:         make(map[uint32]*Stream),
@@ -335,11 +345,11 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		streamQuota:           defaultMaxStreamsClient,
 		streamsQuotaAvailable: make(chan struct{}, 1),
 		czData:                new(channelzData),
-		onGoAway:              onGoAway,
 		keepaliveEnabled:      keepaliveEnabled,
 		bufferPool:            newBufferPool(),
 		onClose:               onClose,
 	}
+	t.logger = prefixLoggerForClientTransport(t)
 	// Add peer information to the http2client context.
 	t.ctx = peer.NewContext(t.ctx, t.getPeer())
 
@@ -438,17 +448,8 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		return nil, err
 	}
 	go func() {
-		t.loopy = newLoopyWriter(clientSide, t.framer, t.controlBuf, t.bdpEst)
-		err := t.loopy.run()
-		if err != nil {
-			if logger.V(logLevel) {
-				logger.Errorf("transport: loopyWriter.run returning. Err: %v", err)
-			}
-		}
-		// Do not close the transport.  Let reader goroutine handle it since
-		// there might be data in the buffers.
-		t.conn.Close()
-		t.controlBuf.finish()
+		t.loopy = newLoopyWriter(clientSide, t.framer, t.controlBuf, t.bdpEst, t.conn, t.logger)
+		t.loopy.run()
 		close(t.writerDone)
 	}()
 	return t, nil
@@ -493,8 +494,9 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 
 func (t *http2Client) getPeer() *peer.Peer {
 	return &peer.Peer{
-		Addr:     t.remoteAddr,
-		AuthInfo: t.authInfo, // Can be nil
+		Addr:      t.remoteAddr,
+		AuthInfo:  t.authInfo, // Can be nil
+		LocalAddr: t.localAddr,
 	}
 }
 
@@ -702,6 +704,18 @@ func (e NewStreamError) Error() string {
 // streams.  All non-nil errors returned will be *NewStreamError.
 func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream, error) {
 	ctx = peer.NewContext(ctx, t.getPeer())
+
+	// ServerName field of the resolver returned address takes precedence over
+	// Host field of CallHdr to determine the :authority header. This is because,
+	// the ServerName field takes precedence for server authentication during
+	// TLS handshake, and the :authority header should match the value used
+	// for server authentication.
+	if t.address.ServerName != "" {
+		newCallHdr := *callHdr
+		newCallHdr.Host = t.address.ServerName
+		callHdr = &newCallHdr
+	}
+
 	headerFields, err := t.createHeaderFields(ctx, callHdr)
 	if err != nil {
 		return nil, &NewStreamError{Err: err, AllowTransparentRetry: false}
@@ -726,15 +740,12 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 		endStream: false,
 		initStream: func(id uint32) error {
 			t.mu.Lock()
-			if state := t.state; state != reachable {
+			// TODO: handle transport closure in loopy instead and remove this
+			// initStream is never called when transport is draining.
+			if t.state == closing {
 				t.mu.Unlock()
-				// Do a quick cleanup.
-				err := error(errStreamDrain)
-				if state == closing {
-					err = ErrConnClosing
-				}
-				cleanup(err)
-				return err
+				cleanup(ErrConnClosing)
+				return ErrConnClosing
 			}
 			if channelz.IsOn() {
 				atomic.AddInt64(&t.czData.streamsStarted, 1)
@@ -752,7 +763,8 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 	}
 	firstTry := true
 	var ch chan struct{}
-	checkForStreamQuota := func(it interface{}) bool {
+	transportDrainRequired := false
+	checkForStreamQuota := func(it any) bool {
 		if t.streamQuota <= 0 { // Can go negative if server decreases it.
 			if firstTry {
 				t.waitingStreams++
@@ -767,10 +779,15 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 		h := it.(*headerFrame)
 		h.streamID = t.nextID
 		t.nextID += 2
+
+		// Drain client transport if nextID > MaxStreamID which signals gRPC that
+		// the connection is closed and a new one must be created for subsequent RPCs.
+		transportDrainRequired = t.nextID > MaxStreamID
+
 		s.id = h.streamID
 		s.fc = &inFlow{limit: uint32(t.initialWindowSize)}
 		t.mu.Lock()
-		if t.activeStreams == nil { // Can be niled from Close().
+		if t.state == draining || t.activeStreams == nil { // Can be niled from Close().
 			t.mu.Unlock()
 			return false // Don't create a stream if the transport is already closed.
 		}
@@ -785,7 +802,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 		return true
 	}
 	var hdrListSizeErr error
-	checkForHeaderListSize := func(it interface{}) bool {
+	checkForHeaderListSize := func(it any) bool {
 		if t.maxSendHeaderListSize == nil {
 			return true
 		}
@@ -800,7 +817,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 		return true
 	}
 	for {
-		success, err := t.controlBuf.executeAndPut(func(it interface{}) bool {
+		success, err := t.controlBuf.executeAndPut(func(it any) bool {
 			return checkForHeaderListSize(it) && checkForStreamQuota(it)
 		}, hdr)
 		if err != nil {
@@ -846,6 +863,12 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream,
 			sh.HandleRPC(s.ctx, outHeader)
 		}
 	}
+	if transportDrainRequired {
+		if t.logger.V(logLevel) {
+			t.logger.Infof("Draining transport: t.nextID > MaxStreamID")
+		}
+		t.GracefulClose()
+	}
 	return s, nil
 }
 
@@ -906,7 +929,7 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 		rst:     rst,
 		rstCode: rstCode,
 	}
-	addBackStreamQuota := func(interface{}) bool {
+	addBackStreamQuota := func(any) bool {
 		t.streamQuota++
 		if t.streamQuota > 0 && t.waitingStreams > 0 {
 			select {
@@ -934,9 +957,14 @@ func (t *http2Client) Close(err error) {
 		t.mu.Unlock()
 		return
 	}
+	if t.logger.V(logLevel) {
+		t.logger.Infof("Closing: %v", err)
+	}
 	// Call t.onClose ASAP to prevent the client from attempting to create new
 	// streams.
-	t.onClose()
+	if t.state != draining {
+		t.onClose(GoAwayInvalid)
+	}
 	t.state = closing
 	streams := t.activeStreams
 	t.activeStreams = nil
@@ -986,11 +1014,15 @@ func (t *http2Client) GracefulClose() {
 		t.mu.Unlock()
 		return
 	}
+	if t.logger.V(logLevel) {
+		t.logger.Infof("GracefulClose called")
+	}
+	t.onClose(GoAwayInvalid)
 	t.state = draining
 	active := len(t.activeStreams)
 	t.mu.Unlock()
 	if active == 0 {
-		t.Close(ErrConnClosing)
+		t.Close(connectionErrorf(true, nil, "no active streams left to process while draining"))
 		return
 	}
 	t.controlBuf.put(&incomingGoAway{})
@@ -1050,7 +1082,7 @@ func (t *http2Client) updateWindow(s *Stream, n uint32) {
 // for the transport and the stream based on the current bdp
 // estimation.
 func (t *http2Client) updateFlowControl(n uint32) {
-	updateIWS := func(interface{}) bool {
+	updateIWS := func(any) bool {
 		t.initialWindowSize = int32(n)
 		t.mu.Lock()
 		for _, s := range t.activeStreams {
@@ -1147,8 +1179,8 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 	}
 	statusCode, ok := http2ErrConvTab[f.ErrCode]
 	if !ok {
-		if logger.V(logLevel) {
-			logger.Warningf("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error %v", f.ErrCode)
+		if t.logger.V(logLevel) {
+			t.logger.Infof("Received a RST_STREAM frame with code %q, but found no mapped gRPC status", f.ErrCode)
 		}
 		statusCode = codes.Unknown
 	}
@@ -1203,7 +1235,7 @@ func (t *http2Client) handleSettings(f *http2.SettingsFrame, isFirst bool) {
 		}
 		updateFuncs = append(updateFuncs, updateStreamQuota)
 	}
-	t.controlBuf.executeAndPut(func(interface{}) bool {
+	t.controlBuf.executeAndPut(func(any) bool {
 		for _, f := range updateFuncs {
 			f()
 		}
@@ -1230,10 +1262,12 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 		t.mu.Unlock()
 		return
 	}
-	if f.ErrCode == http2.ErrCodeEnhanceYourCalm {
-		if logger.V(logLevel) {
-			logger.Infof("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
-		}
+	if f.ErrCode == http2.ErrCodeEnhanceYourCalm && string(f.DebugData()) == "too_many_pings" {
+		// When a client receives a GOAWAY with error code ENHANCE_YOUR_CALM and debug
+		// data equal to ASCII "too_many_pings", it should log the occurrence at a log level that is
+		// enabled by default and double the configure KEEPALIVE_TIME used for new connections
+		// on that channel.
+		logger.Errorf("Client received GoAway with error code ENHANCE_YOUR_CALM and debug data equal to ASCII \"too_many_pings\".")
 	}
 	id := f.LastStreamID
 	if id > 0 && id%2 == 0 {
@@ -1266,8 +1300,10 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 		// Notify the clientconn about the GOAWAY before we set the state to
 		// draining, to allow the client to stop attempting to create streams
 		// before disallowing new streams on this connection.
-		t.onGoAway(t.goAwayReason)
-		t.state = draining
+		if t.state != draining {
+			t.onClose(t.goAwayReason)
+			t.state = draining
+		}
 	}
 	// All streams with IDs greater than the GoAwayId
 	// and smaller than the previous GoAway ID should be killed.
@@ -1303,7 +1339,7 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 
 // setGoAwayReason sets the value of t.goAwayReason based
 // on the GoAway frame received.
-// It expects a lock on transport's mutext to be held by
+// It expects a lock on transport's mutex to be held by
 // the caller.
 func (t *http2Client) setGoAwayReason(f *http2.GoAwayFrame) {
 	t.goAwayReason = GoAwayNoReason
@@ -1365,7 +1401,6 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		mdata          = make(map[string][]string)
 		contentTypeErr = "malformed header: missing HTTP content-type"
 		grpcMessage    string
-		statusGen      *status.Status
 		recvCompress   string
 		httpStatusCode *int
 		httpStatusErr  string
@@ -1400,12 +1435,6 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 			rawStatusCode = codes.Code(uint32(code))
 		case "grpc-message":
 			grpcMessage = decodeGrpcMessage(hf.Value)
-		case "grpc-status-details-bin":
-			var err error
-			statusGen, err = decodeGRPCStatusDetails(hf.Value)
-			if err != nil {
-				headerError = fmt.Sprintf("transport: malformed grpc-status-details-bin: %v", err)
-			}
 		case ":status":
 			if hf.Value == "200" {
 				httpStatusErr = ""
@@ -1471,14 +1500,15 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		return
 	}
 
-	isHeader := false
-
-	// If headerChan hasn't been closed yet
-	if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
-		s.headerValid = true
-		if !endStream {
-			// HEADERS frame block carries a Response-Headers.
-			isHeader = true
+	// For headers, set them in s.header and close headerChan.  For trailers or
+	// trailers-only, closeStream will set the trailers and close headerChan as
+	// needed.
+	if !endStream {
+		// If headerChan hasn't been closed yet (expected, given we checked it
+		// above, but something else could have potentially closed the whole
+		// stream).
+		if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
+			s.headerValid = true
 			// These values can be set without any synchronization because
 			// stream goroutine will read it only after seeing a closed
 			// headerChan which we'll close after setting this.
@@ -1486,15 +1516,12 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 			if len(mdata) > 0 {
 				s.header = mdata
 			}
-		} else {
-			// HEADERS frame block carries a Trailers-Only.
-			s.noHeaders = true
+			close(s.headerChan)
 		}
-		close(s.headerChan)
 	}
 
 	for _, sh := range t.statsHandlers {
-		if isHeader {
+		if !endStream {
 			inHeader := &stats.InHeader{
 				Client:      true,
 				WireLength:  int(frame.Header().Length),
@@ -1516,13 +1543,12 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		return
 	}
 
-	if statusGen == nil {
-		statusGen = status.New(rawStatusCode, grpcMessage)
-	}
+	status := istatus.NewWithProto(rawStatusCode, grpcMessage, mdata[grpcStatusDetailsBinHeader])
 
-	// if client received END_STREAM from server while stream was still active, send RST_STREAM
-	rst := s.getState() == streamActive
-	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, statusGen, mdata, true)
+	// If client received END_STREAM from server while stream was still active,
+	// send RST_STREAM.
+	rstStream := s.getState() == streamActive
+	t.closeStream(s, io.EOF, rstStream, http2.ErrCodeNo, status, mdata, true)
 }
 
 // readServerPreface reads and handles the initial settings frame from the
@@ -1756,3 +1782,9 @@ func (t *http2Client) getOutFlowWindow() int64 {
 		return -2
 	}
 }
+
+func (t *http2Client) stateForTesting() transportState {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.state
+}

vendor/google.golang.org/grpc/internal/transport/http2_server.go

@@ -21,6 +21,7 @@ package transport
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -34,13 +35,16 @@ import (
 	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	"google.golang.org/grpc/internal/grpclog"
 	"google.golang.org/grpc/internal/grpcutil"
+	"google.golang.org/grpc/internal/pretty"
 	"google.golang.org/grpc/internal/syscall"
 
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
+	"google.golang.org/grpc/internal/grpcsync"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
@@ -64,18 +68,15 @@ var serverConnectionCounter uint64
 
 // http2Server implements the ServerTransport interface with HTTP2.
 type http2Server struct {
-	lastRead    int64 // Keep this field 64-bit aligned. Accessed atomically.
-	ctx         context.Context
-	done        chan struct{}
-	conn        net.Conn
-	loopy       *loopyWriter
-	readerDone  chan struct{} // sync point to enable testing.
-	writerDone  chan struct{} // sync point to enable testing.
-	remoteAddr  net.Addr
-	localAddr   net.Addr
-	authInfo    credentials.AuthInfo // auth info about the connection
-	inTapHandle tap.ServerInHandle
-	framer      *framer
+	lastRead        int64 // Keep this field 64-bit aligned. Accessed atomically.
+	done            chan struct{}
+	conn            net.Conn
+	loopy           *loopyWriter
+	readerDone      chan struct{} // sync point to enable testing.
+	loopyWriterDone chan struct{}
+	peer            peer.Peer
+	inTapHandle     tap.ServerInHandle
+	framer          *framer
 	// The max number of concurrent streams.
 	maxStreams uint32
 	// controlBuf delivers all the control related tasks (e.g., window
@@ -101,13 +102,13 @@ type http2Server struct {
 
 	mu sync.Mutex // guard the following
 
-	// drainChan is initialized when Drain() is called the first time.
-	// After which the server writes out the first GoAway(with ID 2^31-1) frame.
-	// Then an independent goroutine will be launched to later send the second GoAway.
-	// During this time we don't want to write another first GoAway(with ID 2^31 -1) frame.
-	// Thus call to Drain() will be a no-op if drainChan is already initialized since draining is
-	// already underway.
-	drainChan     chan struct{}
+	// drainEvent is initialized when Drain() is called the first time. After
+	// which the server writes out the first GoAway(with ID 2^31-1) frame. Then
+	// an independent goroutine will be launched to later send the second
+	// GoAway. During this time we don't want to write another first GoAway(with
+	// ID 2^31 -1) frame. Thus call to Drain() will be a no-op if drainEvent is
+	// already initialized since draining is already underway.
+	drainEvent    *grpcsync.Event
 	state         transportState
 	activeStreams map[uint32]*Stream
 	// idle is the time instant when the connection went idle.
@@ -127,6 +128,8 @@ type http2Server struct {
 	// This lock may not be taken if mu is already held.
 	maxStreamMu sync.Mutex
 	maxStreamID uint32 // max stream ID ever seen
+
+	logger *grpclog.PrefixLogger
 }
 
 // NewServerTransport creates a http2 transport with conn and configuration
@@ -159,21 +162,16 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 	if config.MaxHeaderListSize != nil {
 		maxHeaderListSize = *config.MaxHeaderListSize
 	}
-	framer := newFramer(conn, writeBufSize, readBufSize, maxHeaderListSize)
+	framer := newFramer(conn, writeBufSize, readBufSize, config.SharedWriteBuffer, maxHeaderListSize)
 	// Send initial settings as connection preface to client.
 	isettings := []http2.Setting{{
 		ID:  http2.SettingMaxFrameSize,
 		Val: http2MaxFrameLen,
 	}}
-	// TODO(zhaoq): Have a better way to signal "no limit" because 0 is
-	// permitted in the HTTP2 spec.
-	maxStreams := config.MaxStreams
-	if maxStreams == 0 {
-		maxStreams = math.MaxUint32
-	} else {
+	if config.MaxStreams != math.MaxUint32 {
 		isettings = append(isettings, http2.Setting{
 			ID:  http2.SettingMaxConcurrentStreams,
-			Val: maxStreams,
+			Val: config.MaxStreams,
 		})
 	}
 	dynamicWindow := true
@@ -232,7 +230,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 		kp.Timeout = defaultServerKeepaliveTimeout
 	}
 	if kp.Time != infinity {
-		if err = syscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil {
+		if err = syscall.SetTCPUserTimeout(rawConn, kp.Timeout); err != nil {
 			return nil, connectionErrorf(false, err, "transport: failed to set TCP_USER_TIMEOUT: %v", err)
 		}
 	}
@@ -242,17 +240,19 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 	}
 
 	done := make(chan struct{})
+	peer := peer.Peer{
+		Addr:      conn.RemoteAddr(),
+		LocalAddr: conn.LocalAddr(),
+		AuthInfo:  authInfo,
+	}
 	t := &http2Server{
-		ctx:               setConnection(context.Background(), rawConn),
 		done:              done,
 		conn:              conn,
-		remoteAddr:        conn.RemoteAddr(),
-		localAddr:         conn.LocalAddr(),
-		authInfo:          authInfo,
+		peer:              peer,
 		framer:            framer,
 		readerDone:        make(chan struct{}),
-		writerDone:        make(chan struct{}),
-		maxStreams:        maxStreams,
+		loopyWriterDone:   make(chan struct{}),
+		maxStreams:        config.MaxStreams,
 		inTapHandle:       config.InTapHandle,
 		fc:                &trInFlow{limit: uint32(icwz)},
 		state:             reachable,
@@ -265,8 +265,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 		czData:            new(channelzData),
 		bufferPool:        newBufferPool(),
 	}
-	// Add peer information to the http2server context.
-	t.ctx = peer.NewContext(t.ctx, t.getPeer())
+	t.logger = prefixLoggerForServerTransport(t)
 
 	t.controlBuf = newControlBuffer(t.done)
 	if dynamicWindow {
@@ -275,15 +274,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 			updateFlowControl: t.updateFlowControl,
 		}
 	}
-	for _, sh := range t.stats {
-		t.ctx = sh.TagConn(t.ctx, &stats.ConnTagInfo{
-			RemoteAddr: t.remoteAddr,
-			LocalAddr:  t.localAddr,
-		})
-		connBegin := &stats.ConnBegin{}
-		sh.HandleConn(t.ctx, connBegin)
-	}
-	t.channelzID, err = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.remoteAddr, t.localAddr))
+	t.channelzID, err = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.peer.Addr, t.peer.LocalAddr))
 	if err != nil {
 		return nil, err
 	}
@@ -293,7 +284,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 
 	defer func() {
 		if err != nil {
-			t.Close()
+			t.Close(err)
 		}
 	}()
 
@@ -329,23 +320,18 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 	t.handleSettings(sf)
 
 	go func() {
-		t.loopy = newLoopyWriter(serverSide, t.framer, t.controlBuf, t.bdpEst)
+		t.loopy = newLoopyWriter(serverSide, t.framer, t.controlBuf, t.bdpEst, t.conn, t.logger)
 		t.loopy.ssGoAwayHandler = t.outgoingGoAwayHandler
-		if err := t.loopy.run(); err != nil {
-			if logger.V(logLevel) {
-				logger.Errorf("transport: loopyWriter.run returning. Err: %v", err)
-			}
-		}
-		t.conn.Close()
-		t.controlBuf.finish()
-		close(t.writerDone)
+		t.loopy.run()
+		close(t.loopyWriterDone)
 	}()
 	go t.keepalive()
 	return t, nil
 }
 
-// operateHeader takes action on the decoded headers.
-func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (fatal bool) {
+// operateHeaders takes action on the decoded headers. Returns an error if fatal
+// error encountered and transport needs to close, otherwise returns nil.
+func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeadersFrame, handle func(*Stream)) error {
 	// Acquire max stream ID lock for entire duration
 	t.maxStreamMu.Lock()
 	defer t.maxStreamMu.Unlock()
@@ -361,33 +347,32 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 			rstCode:  http2.ErrCodeFrameSize,
 			onWrite:  func() {},
 		})
-		return false
+		return nil
 	}
 
 	if streamID%2 != 1 || streamID <= t.maxStreamID {
 		// illegal gRPC stream id.
-		if logger.V(logLevel) {
-			logger.Errorf("transport: http2Server.HandleStreams received an illegal stream id: %v", streamID)
-		}
-		return true
+		return fmt.Errorf("received an illegal stream id: %v. headers frame: %+v", streamID, frame)
 	}
 	t.maxStreamID = streamID
 
 	buf := newRecvBuffer()
 	s := &Stream{
-		id:  streamID,
-		st:  t,
-		buf: buf,
-		fc:  &inFlow{limit: uint32(t.initialWindowSize)},
+		id:               streamID,
+		st:               t,
+		buf:              buf,
+		fc:               &inFlow{limit: uint32(t.initialWindowSize)},
+		headerWireLength: int(frame.Header().Length),
 	}
 	var (
-		// If a gRPC Response-Headers has already been received, then it means
-		// that the peer is speaking gRPC and we are in gRPC mode.
-		isGRPC     = false
-		mdata      = make(map[string][]string)
-		httpMethod string
-		// headerError is set if an error is encountered while parsing the headers
-		headerError bool
+		// if false, content-type was missing or invalid
+		isGRPC      = false
+		contentType = ""
+		mdata       = make(metadata.MD, len(frame.Fields))
+		httpMethod  string
+		// these are set if an error is encountered while parsing the headers
+		protocolError bool
+		headerError   *status.Status
 
 		timeoutSet bool
 		timeout    time.Duration
@@ -398,11 +383,23 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		case "content-type":
 			contentSubtype, validContentType := grpcutil.ContentSubtype(hf.Value)
 			if !validContentType {
+				contentType = hf.Value
 				break
 			}
 			mdata[hf.Name] = append(mdata[hf.Name], hf.Value)
 			s.contentSubtype = contentSubtype
 			isGRPC = true
+
+		case "grpc-accept-encoding":
+			mdata[hf.Name] = append(mdata[hf.Name], hf.Value)
+			if hf.Value == "" {
+				continue
+			}
+			compressors := hf.Value
+			if s.clientAdvertisedCompressors != "" {
+				compressors = s.clientAdvertisedCompressors + "," + compressors
+			}
+			s.clientAdvertisedCompressors = compressors
 		case "grpc-encoding":
 			s.recvCompress = hf.Value
 		case ":method":
@@ -413,23 +410,23 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 			timeoutSet = true
 			var err error
 			if timeout, err = decodeTimeout(hf.Value); err != nil {
-				headerError = true
+				headerError = status.Newf(codes.Internal, "malformed grpc-timeout: %v", err)
 			}
 		// "Transports must consider requests containing the Connection header
 		// as malformed." - A41
 		case "connection":
-			if logger.V(logLevel) {
-				logger.Errorf("transport: http2Server.operateHeaders parsed a :connection header which makes a request malformed as per the HTTP/2 spec")
+			if t.logger.V(logLevel) {
+				t.logger.Infof("Received a HEADERS frame with a :connection header which makes the request malformed, as per the HTTP/2 spec")
 			}
-			headerError = true
+			protocolError = true
 		default:
 			if isReservedHeader(hf.Name) && !isWhitelistedHeader(hf.Name) {
 				break
 			}
 			v, err := decodeMetadataHeader(hf.Name, hf.Value)
 			if err != nil {
-				headerError = true
-				logger.Warningf("Failed to decode metadata header (%q, %q): %v", hf.Name, hf.Value, err)
+				headerError = status.Newf(codes.Internal, "malformed binary metadata %q in header %q: %v", hf.Value, hf.Name, err)
+				t.logger.Warningf("Failed to decode metadata header (%q, %q): %v", hf.Name, hf.Value, err)
 				break
 			}
 			mdata[hf.Name] = append(mdata[hf.Name], v)
@@ -443,27 +440,47 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	// error, this takes precedence over a client not speaking gRPC.
 	if len(mdata[":authority"]) > 1 || len(mdata["host"]) > 1 {
 		errMsg := fmt.Sprintf("num values of :authority: %v, num values of host: %v, both must only have 1 value as per HTTP/2 spec", len(mdata[":authority"]), len(mdata["host"]))
-		if logger.V(logLevel) {
-			logger.Errorf("transport: %v", errMsg)
+		if t.logger.V(logLevel) {
+			t.logger.Infof("Aborting the stream early: %v", errMsg)
 		}
 		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     400,
+			httpStatus:     http.StatusBadRequest,
 			streamID:       streamID,
 			contentSubtype: s.contentSubtype,
 			status:         status.New(codes.Internal, errMsg),
 			rst:            !frame.StreamEnded(),
 		})
-		return false
+		return nil
 	}
 
-	if !isGRPC || headerError {
+	if protocolError {
 		t.controlBuf.put(&cleanupStream{
 			streamID: streamID,
 			rst:      true,
 			rstCode:  http2.ErrCodeProtocol,
 			onWrite:  func() {},
 		})
-		return false
+		return nil
+	}
+	if !isGRPC {
+		t.controlBuf.put(&earlyAbortStream{
+			httpStatus:     http.StatusUnsupportedMediaType,
+			streamID:       streamID,
+			contentSubtype: s.contentSubtype,
+			status:         status.Newf(codes.InvalidArgument, "invalid gRPC request content-type %q", contentType),
+			rst:            !frame.StreamEnded(),
+		})
+		return nil
+	}
+	if headerError != nil {
+		t.controlBuf.put(&earlyAbortStream{
+			httpStatus:     http.StatusBadRequest,
+			streamID:       streamID,
+			contentSubtype: s.contentSubtype,
+			status:         headerError,
+			rst:            !frame.StreamEnded(),
+		})
+		return nil
 	}
 
 	// "If :authority is missing, Host must be renamed to :authority." - A41
@@ -484,9 +501,9 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		s.state = streamReadDone
 	}
 	if timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(t.ctx, timeout)
+		s.ctx, s.cancel = context.WithTimeout(ctx, timeout)
 	} else {
-		s.ctx, s.cancel = context.WithCancel(t.ctx)
+		s.ctx, s.cancel = context.WithCancel(ctx)
 	}
 
 	// Attach the received metadata to the context.
@@ -503,7 +520,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	if t.state != reachable {
 		t.mu.Unlock()
 		s.cancel()
-		return false
+		return nil
 	}
 	if uint32(len(t.activeStreams)) >= t.maxStreams {
 		t.mu.Unlock()
@@ -514,13 +531,13 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 			onWrite:  func() {},
 		})
 		s.cancel()
-		return false
+		return nil
 	}
 	if httpMethod != http.MethodPost {
 		t.mu.Unlock()
-		errMsg := fmt.Sprintf("http2Server.operateHeaders parsed a :method field: %v which should be POST", httpMethod)
-		if logger.V(logLevel) {
-			logger.Infof("transport: %v", errMsg)
+		errMsg := fmt.Sprintf("Received a HEADERS frame with :method %q which should be POST", httpMethod)
+		if t.logger.V(logLevel) {
+			t.logger.Infof("Aborting the stream early: %v", errMsg)
 		}
 		t.controlBuf.put(&earlyAbortStream{
 			httpStatus:     405,
@@ -530,14 +547,14 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 			rst:            !frame.StreamEnded(),
 		})
 		s.cancel()
-		return false
+		return nil
 	}
 	if t.inTapHandle != nil {
 		var err error
-		if s.ctx, err = t.inTapHandle(s.ctx, &tap.Info{FullMethodName: s.method}); err != nil {
+		if s.ctx, err = t.inTapHandle(s.ctx, &tap.Info{FullMethodName: s.method, Header: mdata}); err != nil {
 			t.mu.Unlock()
-			if logger.V(logLevel) {
-				logger.Infof("transport: http2Server.operateHeaders got an error from InTapHandle: %v", err)
+			if t.logger.V(logLevel) {
+				t.logger.Infof("Aborting the stream early due to InTapHandle failure: %v", err)
 			}
 			stat, ok := status.FromError(err)
 			if !ok {
@@ -550,7 +567,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 				status:         stat,
 				rst:            !frame.StreamEnded(),
 			})
-			return false
+			return nil
 		}
 	}
 	t.activeStreams[streamID] = s
@@ -565,19 +582,6 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	s.requestRead = func(n int) {
 		t.adjustWindow(s, uint32(n))
 	}
-	s.ctx = traceCtx(s.ctx, s.method)
-	for _, sh := range t.stats {
-		s.ctx = sh.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
-		inHeader := &stats.InHeader{
-			FullMethod:  s.method,
-			RemoteAddr:  t.remoteAddr,
-			LocalAddr:   t.localAddr,
-			Compression: s.recvCompress,
-			WireLength:  int(frame.Header().Length),
-			Header:      metadata.MD(mdata).Copy(),
-		}
-		sh.HandleRPC(s.ctx, inHeader)
-	}
 	s.ctxDone = s.ctx.Done()
 	s.wq = newWriteQuota(defaultWriteQuota, s.ctxDone)
 	s.trReader = &transportReader{
@@ -597,22 +601,25 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		wq:       s.wq,
 	})
 	handle(s)
-	return false
+	return nil
 }
 
 // HandleStreams receives incoming streams using the given handler. This is
 // typically run in a separate goroutine.
 // traceCtx attaches trace to ctx and returns the new context.
-func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) {
-	defer close(t.readerDone)
+func (t *http2Server) HandleStreams(ctx context.Context, handle func(*Stream)) {
+	defer func() {
+		<-t.loopyWriterDone
+		close(t.readerDone)
+	}()
 	for {
 		t.controlBuf.throttle()
 		frame, err := t.framer.fr.ReadFrame()
 		atomic.StoreInt64(&t.lastRead, time.Now().UnixNano())
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
-				if logger.V(logLevel) {
-					logger.Warningf("transport: http2Server.HandleStreams encountered http2.StreamError: %v", se)
+				if t.logger.V(logLevel) {
+					t.logger.Warningf("Encountered http2.StreamError: %v", se)
 				}
 				t.mu.Lock()
 				s := t.activeStreams[se.StreamID]
@@ -630,19 +637,16 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 				continue
 			}
 			if err == io.EOF || err == io.ErrUnexpectedEOF {
-				t.Close()
+				t.Close(err)
 				return
 			}
-			if logger.V(logLevel) {
-				logger.Warningf("transport: http2Server.HandleStreams failed to read frame: %v", err)
-			}
-			t.Close()
+			t.Close(err)
 			return
 		}
 		switch frame := frame.(type) {
 		case *http2.MetaHeadersFrame:
-			if t.operateHeaders(frame, handle, traceCtx) {
-				t.Close()
+			if err := t.operateHeaders(ctx, frame, handle); err != nil {
+				t.Close(err)
 				break
 			}
 		case *http2.DataFrame:
@@ -658,8 +662,8 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 		case *http2.GoAwayFrame:
 			// TODO: Handle GoAway from the client appropriately.
 		default:
-			if logger.V(logLevel) {
-				logger.Errorf("transport: http2Server.HandleStreams found unhandled frame type %v.", frame)
+			if t.logger.V(logLevel) {
+				t.logger.Infof("Received unsupported frame type %T", frame)
 			}
 		}
 	}
@@ -826,7 +830,7 @@ func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
 		}
 		return nil
 	})
-	t.controlBuf.executeAndPut(func(interface{}) bool {
+	t.controlBuf.executeAndPut(func(any) bool {
 		for _, f := range updateFuncs {
 			f()
 		}
@@ -843,8 +847,8 @@ const (
 
 func (t *http2Server) handlePing(f *http2.PingFrame) {
 	if f.IsAck() {
-		if f.Data == goAwayPing.data && t.drainChan != nil {
-			close(t.drainChan)
+		if f.Data == goAwayPing.data && t.drainEvent != nil {
+			t.drainEvent.Fire()
 			return
 		}
 		// Maybe it's a BDP ping.
@@ -886,10 +890,7 @@ func (t *http2Server) handlePing(f *http2.PingFrame) {
 
 	if t.pingStrikes > maxPingStrikes {
 		// Send goaway and close the connection.
-		if logger.V(logLevel) {
-			logger.Errorf("transport: Got too many pings from the client, closing the connection.")
-		}
-		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings"), closeConn: true})
+		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings"), closeConn: errors.New("got too many pings from the client")})
 	}
 }
 
@@ -913,7 +914,7 @@ func appendHeaderFieldsFromMD(headerFields []hpack.HeaderField, md metadata.MD)
 	return headerFields
 }
 
-func (t *http2Server) checkForHeaderListSize(it interface{}) bool {
+func (t *http2Server) checkForHeaderListSize(it any) bool {
 	if t.maxSendHeaderListSize == nil {
 		return true
 	}
@@ -921,8 +922,8 @@ func (t *http2Server) checkForHeaderListSize(it interface{}) bool {
 	var sz int64
 	for _, f := range hdrFrame.hf {
 		if sz += int64(f.Size()); sz > int64(*t.maxSendHeaderListSize) {
-			if logger.V(logLevel) {
-				logger.Errorf("header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
+			if t.logger.V(logLevel) {
+				t.logger.Infof("Header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
 			}
 			return false
 		}
@@ -1032,12 +1033,15 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 	headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
 
 	if p := st.Proto(); p != nil && len(p.Details) > 0 {
+		// Do not use the user's grpc-status-details-bin (if present) if we are
+		// even attempting to set our own.
+		delete(s.trailer, grpcStatusDetailsBinHeader)
 		stBytes, err := proto.Marshal(p)
 		if err != nil {
 			// TODO: return error instead, when callers are able to handle it.
-			logger.Errorf("transport: failed to marshal rpc status: %v, error: %v", p, err)
+			t.logger.Errorf("Failed to marshal rpc status: %s, error: %v", pretty.ToJSON(p), err)
 		} else {
-			headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status-details-bin", Value: encodeBinHeader(stBytes)})
+			headerFields = append(headerFields, hpack.HeaderField{Name: grpcStatusDetailsBinHeader, Value: encodeBinHeader(stBytes)})
 		}
 	}
 
@@ -1140,20 +1144,20 @@ func (t *http2Server) keepalive() {
 			if val <= 0 {
 				// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
 				// Gracefully close the connection.
-				t.Drain()
+				t.Drain("max_idle")
 				return
 			}
 			idleTimer.Reset(val)
 		case <-ageTimer.C:
-			t.Drain()
+			t.Drain("max_age")
 			ageTimer.Reset(t.kp.MaxConnectionAgeGrace)
 			select {
 			case <-ageTimer.C:
 				// Close the connection after grace period.
-				if logger.V(logLevel) {
-					logger.Infof("transport: closing server transport due to maximum connection age.")
+				if t.logger.V(logLevel) {
+					t.logger.Infof("Closing server transport due to maximum connection age")
 				}
-				t.Close()
+				t.controlBuf.put(closeConnection{})
 			case <-t.done:
 			}
 			return
@@ -1169,10 +1173,7 @@ func (t *http2Server) keepalive() {
 				continue
 			}
 			if outstandingPing && kpTimeoutLeft <= 0 {
-				if logger.V(logLevel) {
-					logger.Infof("transport: closing server transport due to idleness.")
-				}
-				t.Close()
+				t.Close(fmt.Errorf("keepalive ping not acked within timeout %s", t.kp.Time))
 				return
 			}
 			if !outstandingPing {
@@ -1199,30 +1200,29 @@ func (t *http2Server) keepalive() {
 // Close starts shutting down the http2Server transport.
 // TODO(zhaoq): Now the destruction is not blocked on any pending streams. This
 // could cause some resource issue. Revisit this later.
-func (t *http2Server) Close() {
+func (t *http2Server) Close(err error) {
 	t.mu.Lock()
 	if t.state == closing {
 		t.mu.Unlock()
 		return
 	}
+	if t.logger.V(logLevel) {
+		t.logger.Infof("Closing: %v", err)
+	}
 	t.state = closing
 	streams := t.activeStreams
 	t.activeStreams = nil
 	t.mu.Unlock()
 	t.controlBuf.finish()
 	close(t.done)
-	if err := t.conn.Close(); err != nil && logger.V(logLevel) {
-		logger.Infof("transport: error closing conn during Close: %v", err)
+	if err := t.conn.Close(); err != nil && t.logger.V(logLevel) {
+		t.logger.Infof("Error closing underlying net.Conn during Close: %v", err)
 	}
 	channelz.RemoveEntry(t.channelzID)
 	// Cancel all active streams.
 	for _, s := range streams {
 		s.cancel()
 	}
-	for _, sh := range t.stats {
-		connEnd := &stats.ConnEnd{}
-		sh.HandleConn(t.ctx, connEnd)
-	}
 }
 
 // deleteStream deletes the stream s from transport's active streams.
@@ -1288,18 +1288,14 @@ func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, eo
 	})
 }
 
-func (t *http2Server) RemoteAddr() net.Addr {
-	return t.remoteAddr
-}
-
-func (t *http2Server) Drain() {
+func (t *http2Server) Drain(debugData string) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
-	if t.drainChan != nil {
+	if t.drainEvent != nil {
 		return
 	}
-	t.drainChan = make(chan struct{})
-	t.controlBuf.put(&goAway{code: http2.ErrCodeNo, debugData: []byte{}, headsUp: true})
+	t.drainEvent = grpcsync.NewEvent()
+	t.controlBuf.put(&goAway{code: http2.ErrCodeNo, debugData: []byte(debugData), headsUp: true})
 }
 
 var goAwayPing = &ping{data: [8]byte{1, 6, 1, 8, 0, 3, 3, 9}}
@@ -1319,19 +1315,17 @@ func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
 		// Stop accepting more streams now.
 		t.state = draining
 		sid := t.maxStreamID
+		retErr := g.closeConn
 		if len(t.activeStreams) == 0 {
-			g.closeConn = true
+			retErr = errors.New("second GOAWAY written and no active streams left to process")
 		}
 		t.mu.Unlock()
 		t.maxStreamMu.Unlock()
 		if err := t.framer.fr.WriteGoAway(sid, g.code, g.debugData); err != nil {
 			return false, err
 		}
-		if g.closeConn {
-			// Abruptly close the connection following the GoAway (via
-			// loopywriter).  But flush out what's inside the buffer first.
-			t.framer.writer.Flush()
-			return false, fmt.Errorf("transport: Connection closing")
+		if retErr != nil {
+			return false, retErr
 		}
 		return true, nil
 	}
@@ -1343,7 +1337,7 @@ func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
 	// originated before the GoAway reaches the client.
 	// After getting the ack or timer expiration send out another GoAway this
 	// time with an ID of the max stream server intends to process.
-	if err := t.framer.fr.WriteGoAway(math.MaxUint32, http2.ErrCodeNo, []byte{}); err != nil {
+	if err := t.framer.fr.WriteGoAway(math.MaxUint32, http2.ErrCodeNo, g.debugData); err != nil {
 		return false, err
 	}
 	if err := t.framer.fr.WritePing(false, goAwayPing.data); err != nil {
@@ -1353,7 +1347,7 @@ func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
 		timer := time.NewTimer(time.Minute)
 		defer timer.Stop()
 		select {
-		case <-t.drainChan:
+		case <-t.drainEvent.Done():
 		case <-timer.C:
 		case <-t.done:
 			return
@@ -1376,11 +1370,11 @@ func (t *http2Server) ChannelzMetric() *channelz.SocketInternalMetric {
 		LastMessageReceivedTimestamp:     time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgRecvTime)),
 		LocalFlowControlWindow:           int64(t.fc.getSize()),
 		SocketOptions:                    channelz.GetSocketOption(t.conn),
-		LocalAddr:                        t.localAddr,
-		RemoteAddr:                       t.remoteAddr,
+		LocalAddr:                        t.peer.LocalAddr,
+		RemoteAddr:                       t.peer.Addr,
 		// RemoteName :
 	}
-	if au, ok := t.authInfo.(credentials.ChannelzSecurityInfo); ok {
+	if au, ok := t.peer.AuthInfo.(credentials.ChannelzSecurityInfo); ok {
 		s.Security = au.GetSecurityValue()
 	}
 	s.RemoteFlowControlWindow = t.getOutFlowWindow()
@@ -1412,10 +1406,12 @@ func (t *http2Server) getOutFlowWindow() int64 {
 	}
 }
 
-func (t *http2Server) getPeer() *peer.Peer {
+// Peer returns the peer of the transport.
+func (t *http2Server) Peer() *peer.Peer {
 	return &peer.Peer{
-		Addr:     t.remoteAddr,
-		AuthInfo: t.authInfo, // Can be nil
+		Addr:      t.peer.Addr,
+		LocalAddr: t.peer.LocalAddr,
+		AuthInfo:  t.peer.AuthInfo, // Can be nil
 	}
 }
 
@@ -1440,6 +1436,6 @@ func GetConnection(ctx context.Context) net.Conn {
 // SetConnection adds the connection to the context to be able to get
 // information about the destination ip and port for an incoming RPC. This also
 // allows any unary or streaming interceptors to see the connection.
-func setConnection(ctx context.Context, conn net.Conn) context.Context {
+func SetConnection(ctx context.Context, conn net.Conn) context.Context {
 	return context.WithValue(ctx, connectionKey{}, conn)
 }

vendor/google.golang.org/grpc/internal/transport/http_util.go

@@ -21,6 +21,7 @@ package transport
 import (
 	"bufio"
 	"encoding/base64"
+	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -29,16 +30,13 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 	"unicode/utf8"
 
-	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
-	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/grpclog"
-	"google.golang.org/grpc/status"
 )
 
 const (
@@ -85,9 +83,10 @@ var (
 		// 504 Gateway timeout - UNAVAILABLE.
 		http.StatusGatewayTimeout: codes.Unavailable,
 	}
-	logger = grpclog.Component("transport")
 )
 
+var grpcStatusDetailsBinHeader = "grpc-status-details-bin"
+
 // isReservedHeader checks whether hdr belongs to HTTP2 headers
 // reserved by gRPC protocol. Any other headers are classified as the
 // user-specified metadata.
@@ -103,7 +102,6 @@ func isReservedHeader(hdr string) bool {
 		"grpc-message",
 		"grpc-status",
 		"grpc-timeout",
-		"grpc-status-details-bin",
 		// Intentionally exclude grpc-previous-rpc-attempts and
 		// grpc-retry-pushback-ms, which are "reserved", but their API
 		// intentionally works via metadata.
@@ -154,18 +152,6 @@ func decodeMetadataHeader(k, v string) (string, error) {
 	return v, nil
 }
 
-func decodeGRPCStatusDetails(rawDetails string) (*status.Status, error) {
-	v, err := decodeBinHeader(rawDetails)
-	if err != nil {
-		return nil, err
-	}
-	st := &spb.Status{}
-	if err = proto.Unmarshal(v, st); err != nil {
-		return nil, err
-	}
-	return status.FromProto(st), nil
-}
-
 type timeoutUnit uint8
 
 const (
@@ -310,6 +296,7 @@ func decodeGrpcMessageUnchecked(msg string) string {
 }
 
 type bufWriter struct {
+	pool      *sync.Pool
 	buf       []byte
 	offset    int
 	batchSize int
@@ -317,12 +304,17 @@ type bufWriter struct {
 	err       error
 }
 
-func newBufWriter(conn net.Conn, batchSize int) *bufWriter {
-	return &bufWriter{
-		buf:       make([]byte, batchSize*2),
+func newBufWriter(conn net.Conn, batchSize int, pool *sync.Pool) *bufWriter {
+	w := &bufWriter{
 		batchSize: batchSize,
 		conn:      conn,
+		pool:      pool,
 	}
+	// this indicates that we should use non shared buf
+	if pool == nil {
+		w.buf = make([]byte, batchSize)
+	}
+	return w
 }
 
 func (w *bufWriter) Write(b []byte) (n int, err error) {
@@ -330,7 +322,12 @@ func (w *bufWriter) Write(b []byte) (n int, err error) {
 		return 0, w.err
 	}
 	if w.batchSize == 0 { // Buffer has been disabled.
-		return w.conn.Write(b)
+		n, err = w.conn.Write(b)
+		return n, toIOError(err)
+	}
+	if w.buf == nil {
+		b := w.pool.Get().(*[]byte)
+		w.buf = *b
 	}
 	for len(b) > 0 {
 		nn := copy(w.buf[w.offset:], b)
@@ -338,13 +335,24 @@ func (w *bufWriter) Write(b []byte) (n int, err error) {
 		w.offset += nn
 		n += nn
 		if w.offset >= w.batchSize {
-			err = w.Flush()
+			err = w.flushKeepBuffer()
 		}
 	}
 	return n, err
 }
 
 func (w *bufWriter) Flush() error {
+	err := w.flushKeepBuffer()
+	// Only release the buffer if we are in a "shared" mode
+	if w.buf != nil && w.pool != nil {
+		b := w.buf
+		w.pool.Put(&b)
+		w.buf = nil
+	}
+	return err
+}
+
+func (w *bufWriter) flushKeepBuffer() error {
 	if w.err != nil {
 		return w.err
 	}
@@ -352,16 +360,39 @@ func (w *bufWriter) Flush() error {
 		return nil
 	}
 	_, w.err = w.conn.Write(w.buf[:w.offset])
+	w.err = toIOError(w.err)
 	w.offset = 0
 	return w.err
 }
 
+type ioError struct {
+	error
+}
+
+func (i ioError) Unwrap() error {
+	return i.error
+}
+
+func isIOError(err error) bool {
+	return errors.As(err, &ioError{})
+}
+
+func toIOError(err error) error {
+	if err == nil {
+		return nil
+	}
+	return ioError{error: err}
+}
+
 type framer struct {
 	writer *bufWriter
 	fr     *http2.Framer
 }
 
-func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, maxHeaderListSize uint32) *framer {
+var writeBufferPoolMap map[int]*sync.Pool = make(map[int]*sync.Pool)
+var writeBufferMutex sync.Mutex
+
+func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, sharedWriteBuffer bool, maxHeaderListSize uint32) *framer {
 	if writeBufferSize < 0 {
 		writeBufferSize = 0
 	}
@@ -369,7 +400,11 @@ func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, maxHeaderList
 	if readBufferSize > 0 {
 		r = bufio.NewReaderSize(r, readBufferSize)
 	}
-	w := newBufWriter(conn, writeBufferSize)
+	var pool *sync.Pool
+	if sharedWriteBuffer {
+		pool = getWriteBufferPool(writeBufferSize)
+	}
+	w := newBufWriter(conn, writeBufferSize, pool)
 	f := &framer{
 		writer: w,
 		fr:     http2.NewFramer(w, r),
@@ -383,6 +418,24 @@ func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, maxHeaderList
 	return f
 }
 
+func getWriteBufferPool(writeBufferSize int) *sync.Pool {
+	writeBufferMutex.Lock()
+	defer writeBufferMutex.Unlock()
+	size := writeBufferSize * 2
+	pool, ok := writeBufferPoolMap[size]
+	if ok {
+		return pool
+	}
+	pool = &sync.Pool{
+		New: func() any {
+			b := make([]byte, size)
+			return &b
+		},
+	}
+	writeBufferPoolMap[size] = pool
+	return pool
+}
+
 // parseDialTarget returns the network and address to pass to dialer.
 func parseDialTarget(target string) (string, string) {
 	net := "tcp"

vendor/google.golang.org/grpc/internal/transport/logging.go

@@ -0,0 +1,40 @@
+/*
+ *
+ * Copyright 2023 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package transport
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/grpclog"
+	internalgrpclog "google.golang.org/grpc/internal/grpclog"
+)
+
+var logger = grpclog.Component("transport")
+
+func prefixLoggerForServerTransport(p *http2Server) *internalgrpclog.PrefixLogger {
+	return internalgrpclog.NewPrefixLogger(logger, fmt.Sprintf("[server-transport %p] ", p))
+}
+
+func prefixLoggerForServerHandlerTransport(p *serverHandlerTransport) *internalgrpclog.PrefixLogger {
+	return internalgrpclog.NewPrefixLogger(logger, fmt.Sprintf("[server-handler-transport %p] ", p))
+}
+
+func prefixLoggerForClientTransport(p *http2Client) *internalgrpclog.PrefixLogger {
+	return internalgrpclog.NewPrefixLogger(logger, fmt.Sprintf("[client-transport %p] ", p))
+}

vendor/google.golang.org/grpc/internal/transport/proxy.go

@@ -28,6 +28,8 @@ import (
 	"net/http"
 	"net/http/httputil"
 	"net/url"
+
+	"google.golang.org/grpc/internal"
 )
 
 const proxyAuthHeaderKey = "Proxy-Authorization"
@@ -112,7 +114,7 @@ func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, backendAddr stri
 // proxyDial dials, connecting to a proxy first if necessary. Checks if a proxy
 // is necessary, dials, does the HTTP CONNECT handshake, and returns the
 // connection.
-func proxyDial(ctx context.Context, addr string, grpcUA string) (conn net.Conn, err error) {
+func proxyDial(ctx context.Context, addr string, grpcUA string) (net.Conn, error) {
 	newAddr := addr
 	proxyURL, err := mapAddress(addr)
 	if err != nil {
@@ -122,15 +124,15 @@ func proxyDial(ctx context.Context, addr string, grpcUA string) (conn net.Conn,
 		newAddr = proxyURL.Host
 	}
 
-	conn, err = (&net.Dialer{}).DialContext(ctx, "tcp", newAddr)
+	conn, err := internal.NetDialerWithTCPKeepalive().DialContext(ctx, "tcp", newAddr)
 	if err != nil {
-		return
+		return nil, err
 	}
-	if proxyURL != nil {
+	if proxyURL == nil {
 		// proxy is disabled if proxyURL is nil.
-		conn, err = doHTTPConnectHandshake(ctx, conn, addr, proxyURL, grpcUA)
+		return conn, err
 	}
-	return
+	return doHTTPConnectHandshake(ctx, conn, addr, proxyURL, grpcUA)
 }
 
 func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {

vendor/google.golang.org/grpc/internal/transport/transport.go

@@ -37,16 +37,13 @@ import (
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/resolver"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
 )
 
-// ErrNoHeaders is used as a signal that a trailers only response was received,
-// and is not a real error.
-var ErrNoHeaders = errors.New("stream has no headers")
-
 const logLevel = 2
 
 type bufferPool struct {
@@ -56,7 +53,7 @@ type bufferPool struct {
 func newBufferPool() *bufferPool {
 	return &bufferPool{
 		pool: sync.Pool{
-			New: func() interface{} {
+			New: func() any {
 				return new(bytes.Buffer)
 			},
 		},
@@ -257,6 +254,9 @@ type Stream struct {
 	fc           *inFlow
 	wq           *writeQuota
 
+	// Holds compressor names passed in grpc-accept-encoding metadata from the
+	// client. This is empty for the client side stream.
+	clientAdvertisedCompressors string
 	// Callback to state application's intentions to read data. This
 	// is used to adjust flow control, if needed.
 	requestRead func(int)
@@ -266,7 +266,8 @@ type Stream struct {
 	// headerValid indicates whether a valid header was received.  Only
 	// meaningful after headerChan is closed (always call waitOnHeader() before
 	// reading its value).  Not valid on server side.
-	headerValid bool
+	headerValid      bool
+	headerWireLength int // Only set on server side.
 
 	// hdrMu protects header and trailer metadata on the server-side.
 	hdrMu sync.Mutex
@@ -345,8 +346,24 @@ func (s *Stream) RecvCompress() string {
 }
 
 // SetSendCompress sets the compression algorithm to the stream.
-func (s *Stream) SetSendCompress(str string) {
-	s.sendCompress = str
+func (s *Stream) SetSendCompress(name string) error {
+	if s.isHeaderSent() || s.getState() == streamDone {
+		return errors.New("transport: set send compressor called after headers sent or stream done")
+	}
+
+	s.sendCompress = name
+	return nil
+}
+
+// SendCompress returns the send compressor name.
+func (s *Stream) SendCompress() string {
+	return s.sendCompress
+}
+
+// ClientAdvertisedCompressors returns the compressor names advertised by the
+// client via grpc-accept-encoding header.
+func (s *Stream) ClientAdvertisedCompressors() string {
+	return s.clientAdvertisedCompressors
 }
 
 // Done returns a channel which is closed when it receives the final status
@@ -371,14 +388,10 @@ func (s *Stream) Header() (metadata.MD, error) {
 	}
 	s.waitOnHeader()
 
-	if !s.headerValid {
+	if !s.headerValid || s.noHeaders {
 		return nil, s.status.Err()
 	}
 
-	if s.noHeaders {
-		return nil, ErrNoHeaders
-	}
-
 	return s.header.Copy(), nil
 }
 
@@ -414,6 +427,12 @@ func (s *Stream) Context() context.Context {
 	return s.ctx
 }
 
+// SetContext sets the context of the stream. This will be deleted once the
+// stats handler callouts all move to gRPC layer.
+func (s *Stream) SetContext(ctx context.Context) {
+	s.ctx = ctx
+}
+
 // Method returns the method for the stream.
 func (s *Stream) Method() string {
 	return s.method
@@ -426,6 +445,12 @@ func (s *Stream) Status() *status.Status {
 	return s.status
 }
 
+// HeaderWireLength returns the size of the headers of the stream as received
+// from the wire. Valid only on the server.
+func (s *Stream) HeaderWireLength() int {
+	return s.headerWireLength
+}
+
 // SetHeader sets the header metadata. This can be called multiple times.
 // Server side only.
 // This should not be called in parallel to other data writes.
@@ -540,6 +565,7 @@ type ServerConfig struct {
 	InitialConnWindowSize int32
 	WriteBufferSize       int
 	ReadBufferSize        int
+	SharedWriteBuffer     bool
 	ChannelzParentID      *channelz.Identifier
 	MaxHeaderListSize     *uint32
 	HeaderTableSize       *uint32
@@ -573,6 +599,8 @@ type ConnectOptions struct {
 	WriteBufferSize int
 	// ReadBufferSize sets the size of read buffer, which in turn determines how much data can be read at most for one read syscall.
 	ReadBufferSize int
+	// SharedWriteBuffer indicates whether connections should reuse write buffer
+	SharedWriteBuffer bool
 	// ChannelzParentID sets the addrConn id which initiate the creation of this client transport.
 	ChannelzParentID *channelz.Identifier
 	// MaxHeaderListSize sets the max (uncompressed) size of header list that is prepared to be received.
@@ -583,8 +611,8 @@ type ConnectOptions struct {
 
 // NewClientTransport establishes the transport with the required ConnectOptions
 // and returns it to the caller.
-func NewClientTransport(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onGoAway func(GoAwayReason), onClose func()) (ClientTransport, error) {
-	return newHTTP2Client(connectCtx, ctx, addr, opts, onGoAway, onClose)
+func NewClientTransport(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onClose func(GoAwayReason)) (ClientTransport, error) {
+	return newHTTP2Client(connectCtx, ctx, addr, opts, onClose)
 }
 
 // Options provides additional hints and information for message
@@ -684,7 +712,7 @@ type ClientTransport interface {
 // Write methods for a given Stream will be called serially.
 type ServerTransport interface {
 	// HandleStreams receives incoming streams using the given handler.
-	HandleStreams(func(*Stream), func(context.Context, string) context.Context)
+	HandleStreams(context.Context, func(*Stream))
 
 	// WriteHeader sends the header metadata for the given stream.
 	// WriteHeader may not be called on all streams.
@@ -701,13 +729,13 @@ type ServerTransport interface {
 	// Close tears down the transport. Once it is called, the transport
 	// should not be accessed any more. All the pending streams and their
 	// handlers will be terminated asynchronously.
-	Close()
+	Close(err error)
 
-	// RemoteAddr returns the remote network address.
-	RemoteAddr() net.Addr
+	// Peer returns the peer of the server transport.
+	Peer() *peer.Peer
 
 	// Drain notifies the client this ServerTransport stops accepting new RPCs.
-	Drain()
+	Drain(debugData string)
 
 	// IncrMsgSent increments the number of message sent through this transport.
 	IncrMsgSent()
@@ -717,7 +745,7 @@ type ServerTransport interface {
 }
 
 // connectionErrorf creates an ConnectionError with the specified error description.
-func connectionErrorf(temp bool, e error, format string, a ...interface{}) ConnectionError {
+func connectionErrorf(temp bool, e error, format string, a ...any) ConnectionError {
 	return ConnectionError{
 		Desc: fmt.Sprintf(format, a...),
 		temp: temp,