diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/internal/transport/http2_client.go')
-rw-r--r-- | vendor/google.golang.org/grpc/internal/transport/http2_client.go | 1491 |
1 files changed, 1491 insertions, 0 deletions
diff --git a/vendor/google.golang.org/grpc/internal/transport/http2_client.go b/vendor/google.golang.org/grpc/internal/transport/http2_client.go new file mode 100644 index 000000000..e73b77a15 --- /dev/null +++ b/vendor/google.golang.org/grpc/internal/transport/http2_client.go @@ -0,0 +1,1491 @@ +/* + * + * Copyright 2014 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 ( + "context" + "fmt" + "io" + "math" + "net" + "strconv" + "strings" + "sync" + "sync/atomic" + "time" + + "golang.org/x/net/http2" + "golang.org/x/net/http2/hpack" + "google.golang.org/grpc/internal/grpcutil" + + "google.golang.org/grpc/codes" + "google.golang.org/grpc/credentials" + "google.golang.org/grpc/internal" + "google.golang.org/grpc/internal/channelz" + "google.golang.org/grpc/internal/syscall" + "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" +) + +// clientConnectionCounter counts the number of connections a client has +// initiated (equal to the number of http2Clients created). Must be accessed +// atomically. +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 + md interface{} + conn net.Conn // underlying communication channel + loopy *loopyWriter + remoteAddr net.Addr + localAddr net.Addr + authInfo credentials.AuthInfo // auth info about the connection + + readerDone chan struct{} // sync point to enable testing. + writerDone chan struct{} // sync point to enable testing. + // goAway is closed to notify the upper layer (i.e., addrConn.transportMonitor) + // that the server sent GoAway on this transport. + goAway chan struct{} + + framer *framer + // controlBuf delivers all the control related tasks (e.g., window + // updates, reset streams, and various settings) to the controller. + controlBuf *controlBuffer + fc *trInFlow + // The scheme used: https if TLS is on, http otherwise. + scheme string + + isSecure bool + + perRPCCreds []credentials.PerRPCCredentials + + kp keepalive.ClientParameters + keepaliveEnabled bool + + statsHandler stats.Handler + + initialWindowSize int32 + + // configured by peer through SETTINGS_MAX_HEADER_LIST_SIZE + maxSendHeaderListSize *uint32 + + bdpEst *bdpEstimator + // onPrefaceReceipt is a callback that client transport calls upon + // receiving server preface to signal that a succefull HTTP2 + // connection was established. + onPrefaceReceipt func() + + maxConcurrentStreams uint32 + streamQuota int64 + streamsQuotaAvailable chan struct{} + waitingStreams uint32 + nextID uint32 + + mu sync.Mutex // guard the following variables + state transportState + activeStreams map[uint32]*Stream + // prevGoAway ID records the Last-Stream-ID in the previous GOAway frame. + prevGoAwayID uint32 + // goAwayReason records the http2.ErrCode and debug data received with the + // GoAway frame. + goAwayReason GoAwayReason + // A condition variable used to signal when the keepalive goroutine should + // go dormant. The condition for dormancy is based on the number of active + // streams and the `PermitWithoutStream` keepalive client parameter. And + // since the number of active streams is guarded by the above mutex, we use + // the same for this condition variable as well. + kpDormancyCond *sync.Cond + // A boolean to track whether the keepalive goroutine is dormant or not. + // This is checked before attempting to signal the above condition + // variable. + kpDormant bool + + // Fields below are for channelz metric collection. + channelzID int64 // channelz unique identification number + czData *channelzData + + onGoAway func(GoAwayReason) + onClose func() + + bufferPool *bufferPool + + connectionID uint64 +} + +func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr string) (net.Conn, error) { + if fn != nil { + return fn(ctx, addr) + } + return (&net.Dialer{}).DialContext(ctx, "tcp", addr) +} + +func isTemporary(err error) bool { + switch err := err.(type) { + case interface { + Temporary() bool + }: + return err.Temporary() + case interface { + Timeout() bool + }: + // Timeouts may be resolved upon retry, and are thus treated as + // temporary. + return err.Timeout() + } + return true +} + +// 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, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (_ *http2Client, err error) { + scheme := "http" + ctx, cancel := context.WithCancel(ctx) + defer func() { + if err != nil { + cancel() + } + }() + + conn, err := dial(connectCtx, opts.Dialer, addr.Addr) + if err != nil { + 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) + } + // Any further errors will close the underlying connection + defer func(conn net.Conn) { + if err != nil { + conn.Close() + } + }(conn) + kp := opts.KeepaliveParams + // Validate keepalive parameters. + if kp.Time == 0 { + kp.Time = defaultClientKeepaliveTime + } + if kp.Timeout == 0 { + kp.Timeout = defaultClientKeepaliveTimeout + } + keepaliveEnabled := false + if kp.Time != infinity { + if err = syscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil { + return nil, connectionErrorf(false, err, "transport: failed to set TCP_USER_TIMEOUT: %v", err) + } + keepaliveEnabled = true + } + var ( + isSecure bool + authInfo credentials.AuthInfo + ) + transportCreds := opts.TransportCredentials + perRPCCreds := opts.PerRPCCredentials + + if b := opts.CredsBundle; b != nil { + if t := b.TransportCredentials(); t != nil { + transportCreds = t + } + if t := b.PerRPCCredentials(); t != nil { + perRPCCreds = append(perRPCCreds, t) + } + } + if transportCreds != nil { + // gRPC, resolver, balancer etc. can specify arbitrary data in the + // Attributes field of resolver.Address, which is shoved into connectCtx + // and passed to the credential handshaker. This makes it possible for + // address specific arbitrary data to reach the credential handshaker. + contextWithHandshakeInfo := internal.NewClientHandshakeInfoContext.(func(context.Context, credentials.ClientHandshakeInfo) context.Context) + connectCtx = contextWithHandshakeInfo(connectCtx, credentials.ClientHandshakeInfo{Attributes: addr.Attributes}) + conn, authInfo, err = transportCreds.ClientHandshake(connectCtx, addr.ServerName, conn) + if err != nil { + return nil, connectionErrorf(isTemporary(err), err, "transport: authentication handshake failed: %v", err) + } + isSecure = true + if transportCreds.Info().SecurityProtocol == "tls" { + scheme = "https" + } + } + dynamicWindow := true + icwz := int32(initialWindowSize) + if opts.InitialConnWindowSize >= defaultWindowSize { + icwz = opts.InitialConnWindowSize + dynamicWindow = false + } + writeBufSize := opts.WriteBufferSize + readBufSize := opts.ReadBufferSize + maxHeaderListSize := defaultClientMaxHeaderListSize + if opts.MaxHeaderListSize != nil { + maxHeaderListSize = *opts.MaxHeaderListSize + } + t := &http2Client{ + ctx: ctx, + ctxDone: ctx.Done(), // Cache Done chan. + cancel: cancel, + userAgent: opts.UserAgent, + md: addr.Metadata, + conn: conn, + remoteAddr: conn.RemoteAddr(), + localAddr: conn.LocalAddr(), + authInfo: authInfo, + readerDone: make(chan struct{}), + writerDone: make(chan struct{}), + goAway: make(chan struct{}), + framer: newFramer(conn, writeBufSize, readBufSize, maxHeaderListSize), + fc: &trInFlow{limit: uint32(icwz)}, + scheme: scheme, + activeStreams: make(map[uint32]*Stream), + isSecure: isSecure, + perRPCCreds: perRPCCreds, + kp: kp, + statsHandler: opts.StatsHandler, + initialWindowSize: initialWindowSize, + onPrefaceReceipt: onPrefaceReceipt, + nextID: 1, + maxConcurrentStreams: defaultMaxStreamsClient, + streamQuota: defaultMaxStreamsClient, + streamsQuotaAvailable: make(chan struct{}, 1), + czData: new(channelzData), + onGoAway: onGoAway, + onClose: onClose, + keepaliveEnabled: keepaliveEnabled, + bufferPool: newBufferPool(), + } + t.controlBuf = newControlBuffer(t.ctxDone) + if opts.InitialWindowSize >= defaultWindowSize { + t.initialWindowSize = opts.InitialWindowSize + dynamicWindow = false + } + if dynamicWindow { + t.bdpEst = &bdpEstimator{ + bdp: initialWindowSize, + updateFlowControl: t.updateFlowControl, + } + } + if t.statsHandler != nil { + t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{ + RemoteAddr: t.remoteAddr, + LocalAddr: t.localAddr, + }) + connBegin := &stats.ConnBegin{ + Client: true, + } + t.statsHandler.HandleConn(t.ctx, connBegin) + } + if channelz.IsOn() { + t.channelzID = channelz.RegisterNormalSocket(t, opts.ChannelzParentID, fmt.Sprintf("%s -> %s", t.localAddr, t.remoteAddr)) + } + if t.keepaliveEnabled { + t.kpDormancyCond = sync.NewCond(&t.mu) + go t.keepalive() + } + // Start the reader goroutine for incoming message. Each transport has + // a dedicated goroutine which reads HTTP2 frame from network. Then it + // dispatches the frame to the corresponding stream entity. + go t.reader() + + // Send connection preface to server. + n, err := t.conn.Write(clientPreface) + if err != nil { + t.Close() + return nil, connectionErrorf(true, err, "transport: failed to write client preface: %v", err) + } + if n != len(clientPreface) { + t.Close() + return nil, connectionErrorf(true, err, "transport: preface mismatch, wrote %d bytes; want %d", n, len(clientPreface)) + } + var ss []http2.Setting + + if t.initialWindowSize != defaultWindowSize { + ss = append(ss, http2.Setting{ + ID: http2.SettingInitialWindowSize, + Val: uint32(t.initialWindowSize), + }) + } + if opts.MaxHeaderListSize != nil { + ss = append(ss, http2.Setting{ + ID: http2.SettingMaxHeaderListSize, + Val: *opts.MaxHeaderListSize, + }) + } + err = t.framer.fr.WriteSettings(ss...) + if err != nil { + t.Close() + return nil, connectionErrorf(true, err, "transport: failed to write initial settings frame: %v", err) + } + // Adjust the connection flow control window if needed. + if delta := uint32(icwz - defaultWindowSize); delta > 0 { + if err := t.framer.fr.WriteWindowUpdate(0, delta); err != nil { + t.Close() + return nil, connectionErrorf(true, err, "transport: failed to write window update: %v", err) + } + } + + t.connectionID = atomic.AddUint64(&clientConnectionCounter, 1) + + if err := t.framer.writer.Flush(); err != nil { + 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) + } + } + // If it's a connection error, let reader goroutine handle it + // since there might be data in the buffers. + if _, ok := err.(net.Error); !ok { + t.conn.Close() + } + close(t.writerDone) + }() + return t, nil +} + +func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream { + // TODO(zhaoq): Handle uint32 overflow of Stream.id. + s := &Stream{ + ct: t, + done: make(chan struct{}), + method: callHdr.Method, + sendCompress: callHdr.SendCompress, + buf: newRecvBuffer(), + headerChan: make(chan struct{}), + contentSubtype: callHdr.ContentSubtype, + } + s.wq = newWriteQuota(defaultWriteQuota, s.done) + s.requestRead = func(n int) { + t.adjustWindow(s, uint32(n)) + } + // The client side stream context should have exactly the same life cycle with the user provided context. + // That means, s.ctx should be read-only. And s.ctx is done iff ctx is done. + // So we use the original context here instead of creating a copy. + s.ctx = ctx + s.trReader = &transportReader{ + reader: &recvBufferReader{ + ctx: s.ctx, + ctxDone: s.ctx.Done(), + recv: s.buf, + closeStream: func(err error) { + t.CloseStream(s, err) + }, + freeBuffer: t.bufferPool.put, + }, + windowHandler: func(n int) { + t.updateWindow(s, uint32(n)) + }, + } + return s +} + +func (t *http2Client) getPeer() *peer.Peer { + return &peer.Peer{ + Addr: t.remoteAddr, + AuthInfo: t.authInfo, + } +} + +func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr) ([]hpack.HeaderField, error) { + aud := t.createAudience(callHdr) + ri := credentials.RequestInfo{ + Method: callHdr.Method, + AuthInfo: t.authInfo, + } + ctxWithRequestInfo := internal.NewRequestInfoContext.(func(context.Context, credentials.RequestInfo) context.Context)(ctx, ri) + authData, err := t.getTrAuthData(ctxWithRequestInfo, aud) + if err != nil { + return nil, err + } + callAuthData, err := t.getCallAuthData(ctxWithRequestInfo, aud, callHdr) + if err != nil { + return nil, err + } + // TODO(mmukhi): Benchmark if the performance gets better if count the metadata and other header fields + // first and create a slice of that exact size. + // Make the slice of certain predictable size to reduce allocations made by append. + hfLen := 7 // :method, :scheme, :path, :authority, content-type, user-agent, te + hfLen += len(authData) + len(callAuthData) + headerFields := make([]hpack.HeaderField, 0, hfLen) + headerFields = append(headerFields, hpack.HeaderField{Name: ":method", Value: "POST"}) + headerFields = append(headerFields, hpack.HeaderField{Name: ":scheme", Value: t.scheme}) + headerFields = append(headerFields, hpack.HeaderField{Name: ":path", Value: callHdr.Method}) + headerFields = append(headerFields, hpack.HeaderField{Name: ":authority", Value: callHdr.Host}) + headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: grpcutil.ContentType(callHdr.ContentSubtype)}) + headerFields = append(headerFields, hpack.HeaderField{Name: "user-agent", Value: t.userAgent}) + headerFields = append(headerFields, hpack.HeaderField{Name: "te", Value: "trailers"}) + if callHdr.PreviousAttempts > 0 { + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-previous-rpc-attempts", Value: strconv.Itoa(callHdr.PreviousAttempts)}) + } + + if callHdr.SendCompress != "" { + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-encoding", Value: callHdr.SendCompress}) + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-accept-encoding", Value: callHdr.SendCompress}) + } + if dl, ok := ctx.Deadline(); ok { + // Send out timeout regardless its value. The server can detect timeout context by itself. + // TODO(mmukhi): Perhaps this field should be updated when actually writing out to the wire. + timeout := time.Until(dl) + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-timeout", Value: grpcutil.EncodeDuration(timeout)}) + } + for k, v := range authData { + headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)}) + } + for k, v := range callAuthData { + headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)}) + } + if b := stats.OutgoingTags(ctx); b != nil { + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-tags-bin", Value: encodeBinHeader(b)}) + } + if b := stats.OutgoingTrace(ctx); b != nil { + headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-trace-bin", Value: encodeBinHeader(b)}) + } + + if md, added, ok := metadata.FromOutgoingContextRaw(ctx); ok { + var k string + for k, vv := range md { + // HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set. + if isReservedHeader(k) { + continue + } + for _, v := range vv { + headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)}) + } + } + for _, vv := range added { + for i, v := range vv { + if i%2 == 0 { + k = v + continue + } + // HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set. + if isReservedHeader(k) { + continue + } + headerFields = append(headerFields, hpack.HeaderField{Name: strings.ToLower(k), Value: encodeMetadataHeader(k, v)}) + } + } + } + if md, ok := t.md.(*metadata.MD); ok { + for k, vv := range *md { + if isReservedHeader(k) { + continue + } + for _, v := range vv { + headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)}) + } + } + } + return headerFields, nil +} + +func (t *http2Client) createAudience(callHdr *CallHdr) string { + // Create an audience string only if needed. + if len(t.perRPCCreds) == 0 && callHdr.Creds == nil { + return "" + } + // Construct URI required to get auth request metadata. + // Omit port if it is the default one. + host := strings.TrimSuffix(callHdr.Host, ":443") + pos := strings.LastIndex(callHdr.Method, "/") + if pos == -1 { + pos = len(callHdr.Method) + } + return "https://" + host + callHdr.Method[:pos] +} + +func (t *http2Client) getTrAuthData(ctx context.Context, audience string) (map[string]string, error) { + if len(t.perRPCCreds) == 0 { + return nil, nil + } + authData := map[string]string{} + for _, c := range t.perRPCCreds { + data, err := c.GetRequestMetadata(ctx, audience) + if err != nil { + if _, ok := status.FromError(err); ok { + return nil, err + } + + return nil, status.Errorf(codes.Unauthenticated, "transport: %v", err) + } + for k, v := range data { + // Capital header names are illegal in HTTP/2. + k = strings.ToLower(k) + authData[k] = v + } + } + return authData, nil +} + +func (t *http2Client) getCallAuthData(ctx context.Context, audience string, callHdr *CallHdr) (map[string]string, error) { + var callAuthData map[string]string + // Check if credentials.PerRPCCredentials were provided via call options. + // Note: if these credentials are provided both via dial options and call + // options, then both sets of credentials will be applied. + if callCreds := callHdr.Creds; callCreds != nil { + if !t.isSecure && callCreds.RequireTransportSecurity() { + return nil, status.Error(codes.Unauthenticated, "transport: cannot send secure credentials on an insecure connection") + } + data, err := callCreds.GetRequestMetadata(ctx, audience) + if err != nil { + return nil, status.Errorf(codes.Internal, "transport: %v", err) + } + callAuthData = make(map[string]string, len(data)) + for k, v := range data { + // Capital header names are illegal in HTTP/2 + k = strings.ToLower(k) + callAuthData[k] = v + } + } + return callAuthData, nil +} + +// PerformedIOError wraps an error to indicate IO may have been performed +// before the error occurred. +type PerformedIOError struct { + Err error +} + +// Error implements error. +func (p PerformedIOError) Error() string { + return p.Err.Error() +} + +// NewStream creates a stream and registers it into the transport as "active" +// streams. +func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) { + ctx = peer.NewContext(ctx, t.getPeer()) + headerFields, err := t.createHeaderFields(ctx, callHdr) + if err != nil { + // We may have performed I/O in the per-RPC creds callback, so do not + // allow transparent retry. + return nil, PerformedIOError{err} + } + s := t.newStream(ctx, callHdr) + cleanup := func(err error) { + if s.swapState(streamDone) == streamDone { + // If it was already done, return. + return + } + // The stream was unprocessed by the server. + atomic.StoreUint32(&s.unprocessed, 1) + s.write(recvMsg{err: err}) + close(s.done) + // If headerChan isn't closed, then close it. + if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) { + close(s.headerChan) + } + } + hdr := &headerFrame{ + hf: headerFields, + endStream: false, + initStream: func(id uint32) error { + t.mu.Lock() + if state := t.state; state != reachable { + t.mu.Unlock() + // Do a quick cleanup. + err := error(errStreamDrain) + if state == closing { + err = ErrConnClosing + } + cleanup(err) + return err + } + t.activeStreams[id] = s + if channelz.IsOn() { + atomic.AddInt64(&t.czData.streamsStarted, 1) + atomic.StoreInt64(&t.czData.lastStreamCreatedTime, time.Now().UnixNano()) + } + // If the keepalive goroutine has gone dormant, wake it up. + if t.kpDormant { + t.kpDormancyCond.Signal() + } + t.mu.Unlock() + return nil + }, + onOrphaned: cleanup, + wq: s.wq, + } + firstTry := true + var ch chan struct{} + checkForStreamQuota := func(it interface{}) bool { + if t.streamQuota <= 0 { // Can go negative if server decreases it. + if firstTry { + t.waitingStreams++ + } + ch = t.streamsQuotaAvailable + return false + } + if !firstTry { + t.waitingStreams-- + } + t.streamQuota-- + h := it.(*headerFrame) + h.streamID = t.nextID + t.nextID += 2 + s.id = h.streamID + s.fc = &inFlow{limit: uint32(t.initialWindowSize)} + if t.streamQuota > 0 && t.waitingStreams > 0 { + select { + case t.streamsQuotaAvailable <- struct{}{}: + default: + } + } + return true + } + var hdrListSizeErr error + checkForHeaderListSize := func(it interface{}) bool { + if t.maxSendHeaderListSize == nil { + return true + } + hdrFrame := it.(*headerFrame) + var sz int64 + for _, f := range hdrFrame.hf { + if sz += int64(f.Size()); sz > int64(*t.maxSendHeaderListSize) { + hdrListSizeErr = status.Errorf(codes.Internal, "header list size to send violates the maximum size (%d bytes) set by server", *t.maxSendHeaderListSize) + return false + } + } + return true + } + for { + success, err := t.controlBuf.executeAndPut(func(it interface{}) bool { + if !checkForStreamQuota(it) { + return false + } + if !checkForHeaderListSize(it) { + return false + } + return true + }, hdr) + if err != nil { + return nil, err + } + if success { + break + } + if hdrListSizeErr != nil { + return nil, hdrListSizeErr + } + firstTry = false + select { + case <-ch: + case <-s.ctx.Done(): + return nil, ContextErr(s.ctx.Err()) + case <-t.goAway: + return nil, errStreamDrain + case <-t.ctx.Done(): + return nil, ErrConnClosing + } + } + if t.statsHandler != nil { + header, ok := metadata.FromOutgoingContext(ctx) + if ok { + header.Set("user-agent", t.userAgent) + } else { + header = metadata.Pairs("user-agent", t.userAgent) + } + // Note: The header fields are compressed with hpack after this call returns. + // No WireLength field is set here. + outHeader := &stats.OutHeader{ + Client: true, + FullMethod: callHdr.Method, + RemoteAddr: t.remoteAddr, + LocalAddr: t.localAddr, + Compression: callHdr.SendCompress, + Header: header, + } + t.statsHandler.HandleRPC(s.ctx, outHeader) + } + return s, nil +} + +// CloseStream clears the footprint of a stream when the stream is not needed any more. +// This must not be executed in reader's goroutine. +func (t *http2Client) CloseStream(s *Stream, err error) { + var ( + rst bool + rstCode http2.ErrCode + ) + if err != nil { + rst = true + rstCode = http2.ErrCodeCancel + } + t.closeStream(s, err, rst, rstCode, status.Convert(err), nil, false) +} + +func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.ErrCode, st *status.Status, mdata map[string][]string, eosReceived bool) { + // Set stream status to done. + if s.swapState(streamDone) == streamDone { + // If it was already done, return. If multiple closeStream calls + // happen simultaneously, wait for the first to finish. + <-s.done + return + } + // status and trailers can be updated here without any synchronization because the stream goroutine will + // only read it after it sees an io.EOF error from read or write and we'll write those errors + // only after updating this. + s.status = st + if len(mdata) > 0 { + s.trailer = mdata + } + if err != nil { + // This will unblock reads eventually. + s.write(recvMsg{err: err}) + } + // If headerChan isn't closed, then close it. + if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) { + s.noHeaders = true + close(s.headerChan) + } + cleanup := &cleanupStream{ + streamID: s.id, + onWrite: func() { + t.mu.Lock() + if t.activeStreams != nil { + delete(t.activeStreams, s.id) + } + t.mu.Unlock() + if channelz.IsOn() { + if eosReceived { + atomic.AddInt64(&t.czData.streamsSucceeded, 1) + } else { + atomic.AddInt64(&t.czData.streamsFailed, 1) + } + } + }, + rst: rst, + rstCode: rstCode, + } + addBackStreamQuota := func(interface{}) bool { + t.streamQuota++ + if t.streamQuota > 0 && t.waitingStreams > 0 { + select { + case t.streamsQuotaAvailable <- struct{}{}: + default: + } + } + return true + } + t.controlBuf.executeAndPut(addBackStreamQuota, cleanup) + // This will unblock write. + close(s.done) +} + +// Close kicks off the shutdown process of the transport. This should be called +// only once on a transport. Once it is called, the transport should not be +// accessed any more. +// +// This method blocks until the addrConn that initiated this transport is +// re-connected. This happens because t.onClose() begins reconnect logic at the +// addrConn level and blocks until the addrConn is successfully connected. +func (t *http2Client) Close() error { + t.mu.Lock() + // Make sure we only Close once. + if t.state == closing { + t.mu.Unlock() + return nil + } + // Call t.onClose before setting the state to closing to prevent the client + // from attempting to create new streams ASAP. + t.onClose() + t.state = closing + streams := t.activeStreams + t.activeStreams = nil + if t.kpDormant { + // If the keepalive goroutine is blocked on this condition variable, we + // should unblock it so that the goroutine eventually exits. + t.kpDormancyCond.Signal() + } + t.mu.Unlock() + t.controlBuf.finish() + t.cancel() + err := t.conn.Close() + if channelz.IsOn() { + channelz.RemoveEntry(t.channelzID) + } + // Notify all active streams. + for _, s := range streams { + t.closeStream(s, ErrConnClosing, false, http2.ErrCodeNo, status.New(codes.Unavailable, ErrConnClosing.Desc), nil, false) + } + if t.statsHandler != nil { + connEnd := &stats.ConnEnd{ + Client: true, + } + t.statsHandler.HandleConn(t.ctx, connEnd) + } + return err +} + +// GracefulClose sets the state to draining, which prevents new streams from +// being created and causes the transport to be closed when the last active +// stream is closed. If there are no active streams, the transport is closed +// immediately. This does nothing if the transport is already draining or +// closing. +func (t *http2Client) GracefulClose() { + t.mu.Lock() + // Make sure we move to draining only from active. + if t.state == draining || t.state == closing { + t.mu.Unlock() + return + } + t.state = draining + active := len(t.activeStreams) + t.mu.Unlock() + if active == 0 { + t.Close() + return + } + t.controlBuf.put(&incomingGoAway{}) +} + +// Write formats the data into HTTP2 data frame(s) and sends it out. The caller +// should proceed only if Write returns nil. +func (t *http2Client) Write(s *Stream, hdr []byte, data []byte, opts *Options) error { + if opts.Last { + // If it's the last message, update stream state. + if !s.compareAndSwapState(streamActive, streamWriteDone) { + return errStreamDone + } + } else if s.getState() != streamActive { + return errStreamDone + } + df := &dataFrame{ + streamID: s.id, + endStream: opts.Last, + h: hdr, + d: data, + } + if hdr != nil || data != nil { // If it's not an empty data frame, check quota. + if err := s.wq.get(int32(len(hdr) + len(data))); err != nil { + return err + } + } + return t.controlBuf.put(df) +} + +func (t *http2Client) getStream(f http2.Frame) *Stream { + t.mu.Lock() + s := t.activeStreams[f.Header().StreamID] + t.mu.Unlock() + return s +} + +// adjustWindow sends out extra window update over the initial window size +// of stream if the application is requesting data larger in size than +// the window. +func (t *http2Client) adjustWindow(s *Stream, n uint32) { + if w := s.fc.maybeAdjust(n); w > 0 { + t.controlBuf.put(&outgoingWindowUpdate{streamID: s.id, increment: w}) + } +} + +// updateWindow adjusts the inbound quota for the stream. +// Window updates will be sent out when the cumulative quota +// exceeds the corresponding threshold. +func (t *http2Client) updateWindow(s *Stream, n uint32) { + if w := s.fc.onRead(n); w > 0 { + t.controlBuf.put(&outgoingWindowUpdate{streamID: s.id, increment: w}) + } +} + +// updateFlowControl updates the incoming flow control windows +// for the transport and the stream based on the current bdp +// estimation. +func (t *http2Client) updateFlowControl(n uint32) { + t.mu.Lock() + for _, s := range t.activeStreams { + s.fc.newLimit(n) + } + t.mu.Unlock() + updateIWS := func(interface{}) bool { + t.initialWindowSize = int32(n) + return true + } + t.controlBuf.executeAndPut(updateIWS, &outgoingWindowUpdate{streamID: 0, increment: t.fc.newLimit(n)}) + t.controlBuf.put(&outgoingSettings{ + ss: []http2.Setting{ + { + ID: http2.SettingInitialWindowSize, + Val: n, + }, + }, + }) +} + +func (t *http2Client) handleData(f *http2.DataFrame) { + size := f.Header().Length + var sendBDPPing bool + if t.bdpEst != nil { + sendBDPPing = t.bdpEst.add(size) + } + // Decouple connection's flow control from application's read. + // An update on connection's flow control should not depend on + // whether user application has read the data or not. Such a + // restriction is already imposed on the stream's flow control, + // and therefore the sender will be blocked anyways. + // Decoupling the connection flow control will prevent other + // active(fast) streams from starving in presence of slow or + // inactive streams. + // + if w := t.fc.onData(size); w > 0 { + t.controlBuf.put(&outgoingWindowUpdate{ + streamID: 0, + increment: w, + }) + } + if sendBDPPing { + // Avoid excessive ping detection (e.g. in an L7 proxy) + // by sending a window update prior to the BDP ping. + + if w := t.fc.reset(); w > 0 { + t.controlBuf.put(&outgoingWindowUpdate{ + streamID: 0, + increment: w, + }) + } + + t.controlBuf.put(bdpPing) + } + // Select the right stream to dispatch. + s := t.getStream(f) + if s == nil { + return + } + if size > 0 { + if err := s.fc.onData(size); err != nil { + t.closeStream(s, io.EOF, true, http2.ErrCodeFlowControl, status.New(codes.Internal, err.Error()), nil, false) + return + } + if f.Header().Flags.Has(http2.FlagDataPadded) { + if w := s.fc.onRead(size - uint32(len(f.Data()))); w > 0 { + t.controlBuf.put(&outgoingWindowUpdate{s.id, w}) + } + } + // TODO(bradfitz, zhaoq): A copy is required here because there is no + // guarantee f.Data() is consumed before the arrival of next frame. + // Can this copy be eliminated? + if len(f.Data()) > 0 { + buffer := t.bufferPool.get() + buffer.Reset() + buffer.Write(f.Data()) + s.write(recvMsg{buffer: buffer}) + } + } + // The server has closed the stream without sending trailers. Record that + // the read direction is closed, and set the status appropriately. + if f.FrameHeader.Flags.Has(http2.FlagDataEndStream) { + t.closeStream(s, io.EOF, false, http2.ErrCodeNo, status.New(codes.Internal, "server closed the stream without sending trailers"), nil, true) + } +} + +func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) { + s := t.getStream(f) + if s == nil { + return + } + if f.ErrCode == http2.ErrCodeRefusedStream { + // The stream was unprocessed by the server. + atomic.StoreUint32(&s.unprocessed, 1) + } + 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) + } + statusCode = codes.Unknown + } + if statusCode == codes.Canceled { + if d, ok := s.ctx.Deadline(); ok && !d.After(time.Now()) { + // Our deadline was already exceeded, and that was likely the cause + // of this cancelation. Alter the status code accordingly. + statusCode = codes.DeadlineExceeded + } + } + t.closeStream(s, io.EOF, false, http2.ErrCodeNo, status.Newf(statusCode, "stream terminated by RST_STREAM with error code: %v", f.ErrCode), nil, false) +} + +func (t *http2Client) handleSettings(f *http2.SettingsFrame, isFirst bool) { + if f.IsAck() { + return + } + var maxStreams *uint32 + var ss []http2.Setting + var updateFuncs []func() + f.ForeachSetting(func(s http2.Setting) error { + switch s.ID { + case http2.SettingMaxConcurrentStreams: + maxStreams = new(uint32) + *maxStreams = s.Val + case http2.SettingMaxHeaderListSize: + updateFuncs = append(updateFuncs, func() { + t.maxSendHeaderListSize = new(uint32) + *t.maxSendHeaderListSize = s.Val + }) + default: + ss = append(ss, s) + } + return nil + }) + if isFirst && maxStreams == nil { + maxStreams = new(uint32) + *maxStreams = math.MaxUint32 + } + sf := &incomingSettings{ + ss: ss, + } + if maxStreams != nil { + updateStreamQuota := func() { + delta := int64(*maxStreams) - int64(t.maxConcurrentStreams) + t.maxConcurrentStreams = *maxStreams + t.streamQuota += delta + if delta > 0 && t.waitingStreams > 0 { + close(t.streamsQuotaAvailable) // wake all of them up. + t.streamsQuotaAvailable = make(chan struct{}, 1) + } + } + updateFuncs = append(updateFuncs, updateStreamQuota) + } + t.controlBuf.executeAndPut(func(interface{}) bool { + for _, f := range updateFuncs { + f() + } + return true + }, sf) +} + +func (t *http2Client) handlePing(f *http2.PingFrame) { + if f.IsAck() { + // Maybe it's a BDP ping. + if t.bdpEst != nil { + t.bdpEst.calculate(f.Data) + } + return + } + pingAck := &ping{ack: true} + copy(pingAck.data[:], f.Data[:]) + t.controlBuf.put(pingAck) +} + +func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) { + t.mu.Lock() + if t.state == closing { + t.mu.Unlock() + return + } + if f.ErrCode == http2.ErrCodeEnhanceYourCalm { + if logger.V(logLevel) { + logger.Infof("Client received GoAway with http2.ErrCodeEnhanceYourCalm.") + } + } + id := f.LastStreamID + if id > 0 && id%2 != 1 { + t.mu.Unlock() + t.Close() + return + } + // A client can receive multiple GoAways from the server (see + // https://github.com/grpc/grpc-go/issues/1387). The idea is that the first + // GoAway will be sent with an ID of MaxInt32 and the second GoAway will be + // sent after an RTT delay with the ID of the last stream the server will + // process. + // + // Therefore, when we get the first GoAway we don't necessarily close any + // streams. While in case of second GoAway we close all streams created after + // the GoAwayId. This way streams that were in-flight while the GoAway from + // server was being sent don't get killed. + select { + case <-t.goAway: // t.goAway has been closed (i.e.,multiple GoAways). + // If there are multiple GoAways the first one should always have an ID greater than the following ones. + if id > t.prevGoAwayID { + t.mu.Unlock() + t.Close() + return + } + default: + t.setGoAwayReason(f) + close(t.goAway) + t.controlBuf.put(&incomingGoAway{}) + // 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 + } + // All streams with IDs greater than the GoAwayId + // and smaller than the previous GoAway ID should be killed. + upperLimit := t.prevGoAwayID + if upperLimit == 0 { // This is the first GoAway Frame. + upperLimit = math.MaxUint32 // Kill all streams after the GoAway ID. + } + for streamID, stream := range t.activeStreams { + if streamID > id && streamID <= upperLimit { + // The stream was unprocessed by the server. + atomic.StoreUint32(&stream.unprocessed, 1) + t.closeStream(stream, errStreamDrain, false, http2.ErrCodeNo, statusGoAway, nil, false) + } + } + t.prevGoAwayID = id + active := len(t.activeStreams) + t.mu.Unlock() + if active == 0 { + t.Close() + } +} + +// 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 +// the caller. +func (t *http2Client) setGoAwayReason(f *http2.GoAwayFrame) { + t.goAwayReason = GoAwayNoReason + switch f.ErrCode { + case http2.ErrCodeEnhanceYourCalm: + if string(f.DebugData()) == "too_many_pings" { + t.goAwayReason = GoAwayTooManyPings + } + } +} + +func (t *http2Client) GetGoAwayReason() GoAwayReason { + t.mu.Lock() + defer t.mu.Unlock() + return t.goAwayReason +} + +func (t *http2Client) handleWindowUpdate(f *http2.WindowUpdateFrame) { + t.controlBuf.put(&incomingWindowUpdate{ + streamID: f.Header().StreamID, + increment: f.Increment, + }) +} + +// operateHeaders takes action on the decoded headers. +func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) { + s := t.getStream(frame) + if s == nil { + return + } + endStream := frame.StreamEnded() + atomic.StoreUint32(&s.bytesReceived, 1) + initialHeader := atomic.LoadUint32(&s.headerChanClosed) == 0 + + if !initialHeader && !endStream { + // As specified by gRPC over HTTP2, a HEADERS frame (and associated CONTINUATION frames) can only appear at the start or end of a stream. Therefore, second HEADERS frame must have EOS bit set. + st := status.New(codes.Internal, "a HEADERS frame cannot appear in the middle of a stream") + t.closeStream(s, st.Err(), true, http2.ErrCodeProtocol, st, nil, false) + return + } + + state := &decodeState{} + // Initialize isGRPC value to be !initialHeader, since if a gRPC Response-Headers has already been received, then it means that the peer is speaking gRPC and we are in gRPC mode. + state.data.isGRPC = !initialHeader + if h2code, err := state.decodeHeader(frame); err != nil { + t.closeStream(s, err, true, h2code, status.Convert(err), nil, endStream) + return + } + + isHeader := false + defer func() { + if t.statsHandler != nil { + if isHeader { + inHeader := &stats.InHeader{ + Client: true, + WireLength: int(frame.Header().Length), + Header: s.header.Copy(), + Compression: s.recvCompress, + } + t.statsHandler.HandleRPC(s.ctx, inHeader) + } else { + inTrailer := &stats.InTrailer{ + Client: true, + WireLength: int(frame.Header().Length), + Trailer: s.trailer.Copy(), + } + t.statsHandler.HandleRPC(s.ctx, inTrailer) + } + } + }() + + // 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 + // 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. + s.recvCompress = state.data.encoding + if len(state.data.mdata) > 0 { + s.header = state.data.mdata + } + } else { + // HEADERS frame block carries a Trailers-Only. + s.noHeaders = true + } + close(s.headerChan) + } + + if !endStream { + return + } + + // 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, state.status(), state.data.mdata, true) +} + +// reader runs as a separate goroutine in charge of reading data from network +// connection. +// +// TODO(zhaoq): currently one reader per transport. Investigate whether this is +// optimal. +// TODO(zhaoq): Check the validity of the incoming frame sequence. +func (t *http2Client) reader() { + defer close(t.readerDone) + // Check the validity of server preface. + frame, err := t.framer.fr.ReadFrame() + if err != nil { + t.Close() // this kicks off resetTransport, so must be last before return + return + } + t.conn.SetReadDeadline(time.Time{}) // reset deadline once we get the settings frame (we didn't time out, yay!) + if t.keepaliveEnabled { + atomic.StoreInt64(&t.lastRead, time.Now().UnixNano()) + } + sf, ok := frame.(*http2.SettingsFrame) + if !ok { + t.Close() // this kicks off resetTransport, so must be last before return + return + } + t.onPrefaceReceipt() + t.handleSettings(sf, true) + + // loop to keep reading incoming messages on this transport. + for { + t.controlBuf.throttle() + frame, err := t.framer.fr.ReadFrame() + if t.keepaliveEnabled { + atomic.StoreInt64(&t.lastRead, time.Now().UnixNano()) + } + if err != nil { + // Abort an active stream if the http2.Framer returns a + // http2.StreamError. This can happen only if the server's response + // is malformed http2. + if se, ok := err.(http2.StreamError); ok { + t.mu.Lock() + s := t.activeStreams[se.StreamID] + t.mu.Unlock() + if s != nil { + // use error detail to provide better err message + code := http2ErrConvTab[se.Code] + errorDetail := t.framer.fr.ErrorDetail() + var msg string + if errorDetail != nil { + msg = errorDetail.Error() + } else { + msg = "received invalid frame" + } + t.closeStream(s, status.Error(code, msg), true, http2.ErrCodeProtocol, status.New(code, msg), nil, false) + } + continue + } else { + // Transport error. + t.Close() + return + } + } + switch frame := frame.(type) { + case *http2.MetaHeadersFrame: + t.operateHeaders(frame) + case *http2.DataFrame: + t.handleData(frame) + case *http2.RSTStreamFrame: + t.handleRSTStream(frame) + case *http2.SettingsFrame: + t.handleSettings(frame, false) + case *http2.PingFrame: + t.handlePing(frame) + case *http2.GoAwayFrame: + t.handleGoAway(frame) + case *http2.WindowUpdateFrame: + t.handleWindowUpdate(frame) + default: + if logger.V(logLevel) { + logger.Errorf("transport: http2Client.reader got unhandled frame type %v.", frame) + } + } + } +} + +func minTime(a, b time.Duration) time.Duration { + if a < b { + return a + } + return b +} + +// keepalive running in a separate goroutune makes sure the connection is alive by sending pings. +func (t *http2Client) keepalive() { + p := &ping{data: [8]byte{}} + // True iff a ping has been sent, and no data has been received since then. + outstandingPing := false + // Amount of time remaining before which we should receive an ACK for the + // last sent ping. + timeoutLeft := time.Duration(0) + // Records the last value of t.lastRead before we go block on the timer. + // This is required to check for read activity since then. + prevNano := time.Now().UnixNano() + timer := time.NewTimer(t.kp.Time) + for { + select { + case <-timer.C: + lastRead := atomic.LoadInt64(&t.lastRead) + if lastRead > prevNano { + // There has been read activity since the last time we were here. + outstandingPing = false + // Next timer should fire at kp.Time seconds from lastRead time. + timer.Reset(time.Duration(lastRead) + t.kp.Time - time.Duration(time.Now().UnixNano())) + prevNano = lastRead + continue + } + if outstandingPing && timeoutLeft <= 0 { + t.Close() + return + } + t.mu.Lock() + if t.state == closing { + // If the transport is closing, we should exit from the + // keepalive goroutine here. If not, we could have a race + // between the call to Signal() from Close() and the call to + // Wait() here, whereby the keepalive goroutine ends up + // blocking on the condition variable which will never be + // signalled again. + t.mu.Unlock() + return + } + if len(t.activeStreams) < 1 && !t.kp.PermitWithoutStream { + // If a ping was sent out previously (because there were active + // streams at that point) which wasn't acked and its timeout + // hadn't fired, but we got here and are about to go dormant, + // we should make sure that we unconditionally send a ping once + // we awaken. + outstandingPing = false + t.kpDormant = true + t.kpDormancyCond.Wait() + } + t.kpDormant = false + t.mu.Unlock() + + // We get here either because we were dormant and a new stream was + // created which unblocked the Wait() call, or because the + // keepalive timer expired. In both cases, we need to send a ping. + if !outstandingPing { + if channelz.IsOn() { + atomic.AddInt64(&t.czData.kpCount, 1) + } + t.controlBuf.put(p) + timeoutLeft = t.kp.Timeout + outstandingPing = true + } + // The amount of time to sleep here is the minimum of kp.Time and + // timeoutLeft. This will ensure that we wait only for kp.Time + // before sending out the next ping (for cases where the ping is + // acked). + sleepDuration := minTime(t.kp.Time, timeoutLeft) + timeoutLeft -= sleepDuration + timer.Reset(sleepDuration) + case <-t.ctx.Done(): + if !timer.Stop() { + <-timer.C + } + return + } + } +} + +func (t *http2Client) Error() <-chan struct{} { + return t.ctx.Done() +} + +func (t *http2Client) GoAway() <-chan struct{} { + return t.goAway +} + +func (t *http2Client) ChannelzMetric() *channelz.SocketInternalMetric { + s := channelz.SocketInternalMetric{ + StreamsStarted: atomic.LoadInt64(&t.czData.streamsStarted), + StreamsSucceeded: atomic.LoadInt64(&t.czData.streamsSucceeded), + StreamsFailed: atomic.LoadInt64(&t.czData.streamsFailed), + MessagesSent: atomic.LoadInt64(&t.czData.msgSent), + MessagesReceived: atomic.LoadInt64(&t.czData.msgRecv), + KeepAlivesSent: atomic.LoadInt64(&t.czData.kpCount), + LastLocalStreamCreatedTimestamp: time.Unix(0, atomic.LoadInt64(&t.czData.lastStreamCreatedTime)), + LastMessageSentTimestamp: time.Unix(0, atomic.LoadInt64(&t.czData.lastMsgSentTime)), + 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, + // RemoteName : + } + if au, ok := t.authInfo.(credentials.ChannelzSecurityInfo); ok { + s.Security = au.GetSecurityValue() + } + s.RemoteFlowControlWindow = t.getOutFlowWindow() + return &s +} + +func (t *http2Client) RemoteAddr() net.Addr { return t.remoteAddr } + +func (t *http2Client) IncrMsgSent() { + atomic.AddInt64(&t.czData.msgSent, 1) + atomic.StoreInt64(&t.czData.lastMsgSentTime, time.Now().UnixNano()) +} + +func (t *http2Client) IncrMsgRecv() { + atomic.AddInt64(&t.czData.msgRecv, 1) + atomic.StoreInt64(&t.czData.lastMsgRecvTime, time.Now().UnixNano()) +} + +func (t *http2Client) getOutFlowWindow() int64 { + resp := make(chan uint32, 1) + timer := time.NewTimer(time.Second) + defer timer.Stop() + t.controlBuf.put(&outFlowControlSizeRequest{resp}) + select { + case sz := <-resp: + return int64(sz) + case <-t.ctxDone: + return -1 + case <-timer.C: + return -2 + } +} |