mirror of
https://github.com/restic/restic.git
synced 2024-08-20 19:33:23 +02:00
1181 lines
35 KiB
Go
1181 lines
35 KiB
Go
/*
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*
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* Copyright 2014 gRPC authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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*/
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package transport
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import (
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"bytes"
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"context"
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"errors"
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"fmt"
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"io"
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"math"
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"net"
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"strconv"
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"sync"
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"sync/atomic"
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"time"
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"github.com/golang/protobuf/proto"
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"golang.org/x/net/http2"
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"golang.org/x/net/http2/hpack"
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"google.golang.org/grpc/codes"
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"google.golang.org/grpc/credentials"
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"google.golang.org/grpc/grpclog"
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"google.golang.org/grpc/internal/channelz"
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"google.golang.org/grpc/internal/grpcrand"
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"google.golang.org/grpc/keepalive"
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"google.golang.org/grpc/metadata"
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"google.golang.org/grpc/peer"
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"google.golang.org/grpc/stats"
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"google.golang.org/grpc/status"
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"google.golang.org/grpc/tap"
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)
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var (
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// ErrIllegalHeaderWrite indicates that setting header is illegal because of
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// the stream's state.
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ErrIllegalHeaderWrite = errors.New("transport: the stream is done or WriteHeader was already called")
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// ErrHeaderListSizeLimitViolation indicates that the header list size is larger
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// than the limit set by peer.
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ErrHeaderListSizeLimitViolation = errors.New("transport: trying to send header list size larger than the limit set by peer")
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)
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// http2Server implements the ServerTransport interface with HTTP2.
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type http2Server struct {
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ctx context.Context
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ctxDone <-chan struct{} // Cache the context.Done() chan
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cancel context.CancelFunc
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conn net.Conn
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loopy *loopyWriter
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readerDone chan struct{} // sync point to enable testing.
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writerDone chan struct{} // sync point to enable testing.
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remoteAddr net.Addr
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localAddr net.Addr
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maxStreamID uint32 // max stream ID ever seen
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authInfo credentials.AuthInfo // auth info about the connection
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inTapHandle tap.ServerInHandle
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framer *framer
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// The max number of concurrent streams.
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maxStreams uint32
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// controlBuf delivers all the control related tasks (e.g., window
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// updates, reset streams, and various settings) to the controller.
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controlBuf *controlBuffer
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fc *trInFlow
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stats stats.Handler
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// Flag to keep track of reading activity on transport.
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// 1 is true and 0 is false.
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activity uint32 // Accessed atomically.
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// Keepalive and max-age parameters for the server.
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kp keepalive.ServerParameters
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// Keepalive enforcement policy.
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kep keepalive.EnforcementPolicy
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// The time instance last ping was received.
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lastPingAt time.Time
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// Number of times the client has violated keepalive ping policy so far.
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pingStrikes uint8
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// Flag to signify that number of ping strikes should be reset to 0.
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// This is set whenever data or header frames are sent.
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// 1 means yes.
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resetPingStrikes uint32 // Accessed atomically.
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initialWindowSize int32
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bdpEst *bdpEstimator
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maxSendHeaderListSize *uint32
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mu sync.Mutex // guard the following
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// drainChan is initialized when drain(...) is called the first time.
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// After which the server writes out the first GoAway(with ID 2^31-1) frame.
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// Then an independent goroutine will be launched to later send the second GoAway.
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// During this time we don't want to write another first GoAway(with ID 2^31 -1) frame.
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// Thus call to drain(...) will be a no-op if drainChan is already initialized since draining is
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// already underway.
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drainChan chan struct{}
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state transportState
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activeStreams map[uint32]*Stream
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// idle is the time instant when the connection went idle.
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// This is either the beginning of the connection or when the number of
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// RPCs go down to 0.
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// When the connection is busy, this value is set to 0.
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idle time.Time
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// Fields below are for channelz metric collection.
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channelzID int64 // channelz unique identification number
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czData *channelzData
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}
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// newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
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// returned if something goes wrong.
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func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) {
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writeBufSize := config.WriteBufferSize
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readBufSize := config.ReadBufferSize
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maxHeaderListSize := defaultServerMaxHeaderListSize
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if config.MaxHeaderListSize != nil {
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maxHeaderListSize = *config.MaxHeaderListSize
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}
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framer := newFramer(conn, writeBufSize, readBufSize, maxHeaderListSize)
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// Send initial settings as connection preface to client.
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var isettings []http2.Setting
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// TODO(zhaoq): Have a better way to signal "no limit" because 0 is
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// permitted in the HTTP2 spec.
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maxStreams := config.MaxStreams
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if maxStreams == 0 {
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maxStreams = math.MaxUint32
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} else {
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isettings = append(isettings, http2.Setting{
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ID: http2.SettingMaxConcurrentStreams,
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Val: maxStreams,
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})
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}
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dynamicWindow := true
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iwz := int32(initialWindowSize)
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if config.InitialWindowSize >= defaultWindowSize {
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iwz = config.InitialWindowSize
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dynamicWindow = false
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}
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icwz := int32(initialWindowSize)
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if config.InitialConnWindowSize >= defaultWindowSize {
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icwz = config.InitialConnWindowSize
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dynamicWindow = false
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}
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if iwz != defaultWindowSize {
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isettings = append(isettings, http2.Setting{
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ID: http2.SettingInitialWindowSize,
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Val: uint32(iwz)})
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}
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if config.MaxHeaderListSize != nil {
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isettings = append(isettings, http2.Setting{
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ID: http2.SettingMaxHeaderListSize,
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Val: *config.MaxHeaderListSize,
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})
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}
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if err := framer.fr.WriteSettings(isettings...); err != nil {
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return nil, connectionErrorf(false, err, "transport: %v", err)
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}
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// Adjust the connection flow control window if needed.
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if delta := uint32(icwz - defaultWindowSize); delta > 0 {
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if err := framer.fr.WriteWindowUpdate(0, delta); err != nil {
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return nil, connectionErrorf(false, err, "transport: %v", err)
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}
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}
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kp := config.KeepaliveParams
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if kp.MaxConnectionIdle == 0 {
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kp.MaxConnectionIdle = defaultMaxConnectionIdle
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}
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if kp.MaxConnectionAge == 0 {
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kp.MaxConnectionAge = defaultMaxConnectionAge
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}
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// Add a jitter to MaxConnectionAge.
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kp.MaxConnectionAge += getJitter(kp.MaxConnectionAge)
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if kp.MaxConnectionAgeGrace == 0 {
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kp.MaxConnectionAgeGrace = defaultMaxConnectionAgeGrace
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}
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if kp.Time == 0 {
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kp.Time = defaultServerKeepaliveTime
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}
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if kp.Timeout == 0 {
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kp.Timeout = defaultServerKeepaliveTimeout
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}
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kep := config.KeepalivePolicy
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if kep.MinTime == 0 {
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kep.MinTime = defaultKeepalivePolicyMinTime
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}
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ctx, cancel := context.WithCancel(context.Background())
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t := &http2Server{
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ctx: ctx,
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cancel: cancel,
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ctxDone: ctx.Done(),
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conn: conn,
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remoteAddr: conn.RemoteAddr(),
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localAddr: conn.LocalAddr(),
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authInfo: config.AuthInfo,
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framer: framer,
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readerDone: make(chan struct{}),
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writerDone: make(chan struct{}),
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maxStreams: maxStreams,
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inTapHandle: config.InTapHandle,
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fc: &trInFlow{limit: uint32(icwz)},
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state: reachable,
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activeStreams: make(map[uint32]*Stream),
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stats: config.StatsHandler,
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kp: kp,
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idle: time.Now(),
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kep: kep,
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initialWindowSize: iwz,
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czData: new(channelzData),
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}
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t.controlBuf = newControlBuffer(t.ctxDone)
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if dynamicWindow {
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t.bdpEst = &bdpEstimator{
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bdp: initialWindowSize,
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updateFlowControl: t.updateFlowControl,
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}
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}
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if t.stats != nil {
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t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{
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RemoteAddr: t.remoteAddr,
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LocalAddr: t.localAddr,
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})
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connBegin := &stats.ConnBegin{}
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t.stats.HandleConn(t.ctx, connBegin)
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}
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if channelz.IsOn() {
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t.channelzID = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.remoteAddr, t.localAddr))
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}
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t.framer.writer.Flush()
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defer func() {
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if err != nil {
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t.Close()
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}
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}()
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// Check the validity of client preface.
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preface := make([]byte, len(clientPreface))
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if _, err := io.ReadFull(t.conn, preface); err != nil {
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return nil, connectionErrorf(false, err, "transport: http2Server.HandleStreams failed to receive the preface from client: %v", err)
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}
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if !bytes.Equal(preface, clientPreface) {
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return nil, connectionErrorf(false, nil, "transport: http2Server.HandleStreams received bogus greeting from client: %q", preface)
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}
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frame, err := t.framer.fr.ReadFrame()
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if err == io.EOF || err == io.ErrUnexpectedEOF {
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return nil, err
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}
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if err != nil {
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return nil, connectionErrorf(false, err, "transport: http2Server.HandleStreams failed to read initial settings frame: %v", err)
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}
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atomic.StoreUint32(&t.activity, 1)
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sf, ok := frame.(*http2.SettingsFrame)
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if !ok {
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return nil, connectionErrorf(false, nil, "transport: http2Server.HandleStreams saw invalid preface type %T from client", frame)
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}
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t.handleSettings(sf)
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go func() {
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t.loopy = newLoopyWriter(serverSide, t.framer, t.controlBuf, t.bdpEst)
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t.loopy.ssGoAwayHandler = t.outgoingGoAwayHandler
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if err := t.loopy.run(); err != nil {
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errorf("transport: loopyWriter.run returning. Err: %v", err)
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}
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t.conn.Close()
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close(t.writerDone)
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}()
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go t.keepalive()
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return t, nil
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}
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// operateHeader takes action on the decoded headers.
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func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (fatal bool) {
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streamID := frame.Header().StreamID
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state := decodeState{serverSide: true}
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if err := state.decodeHeader(frame); err != nil {
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if se, ok := status.FromError(err); ok {
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t.controlBuf.put(&cleanupStream{
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streamID: streamID,
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rst: true,
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rstCode: statusCodeConvTab[se.Code()],
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onWrite: func() {},
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})
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}
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return false
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}
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buf := newRecvBuffer()
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s := &Stream{
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id: streamID,
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st: t,
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buf: buf,
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fc: &inFlow{limit: uint32(t.initialWindowSize)},
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recvCompress: state.encoding,
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method: state.method,
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contentSubtype: state.contentSubtype,
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}
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if frame.StreamEnded() {
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// s is just created by the caller. No lock needed.
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s.state = streamReadDone
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}
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if state.timeoutSet {
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s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout)
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} else {
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s.ctx, s.cancel = context.WithCancel(t.ctx)
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}
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pr := &peer.Peer{
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Addr: t.remoteAddr,
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}
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// Attach Auth info if there is any.
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if t.authInfo != nil {
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pr.AuthInfo = t.authInfo
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}
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s.ctx = peer.NewContext(s.ctx, pr)
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// Attach the received metadata to the context.
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if len(state.mdata) > 0 {
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s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
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}
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if state.statsTags != nil {
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s.ctx = stats.SetIncomingTags(s.ctx, state.statsTags)
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}
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if state.statsTrace != nil {
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s.ctx = stats.SetIncomingTrace(s.ctx, state.statsTrace)
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}
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if t.inTapHandle != nil {
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var err error
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info := &tap.Info{
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FullMethodName: state.method,
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}
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s.ctx, err = t.inTapHandle(s.ctx, info)
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if err != nil {
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warningf("transport: http2Server.operateHeaders got an error from InTapHandle: %v", err)
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t.controlBuf.put(&cleanupStream{
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streamID: s.id,
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rst: true,
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rstCode: http2.ErrCodeRefusedStream,
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onWrite: func() {},
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})
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return false
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}
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}
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t.mu.Lock()
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if t.state != reachable {
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t.mu.Unlock()
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return false
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}
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if uint32(len(t.activeStreams)) >= t.maxStreams {
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t.mu.Unlock()
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t.controlBuf.put(&cleanupStream{
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streamID: streamID,
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rst: true,
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rstCode: http2.ErrCodeRefusedStream,
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onWrite: func() {},
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})
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return false
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}
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if streamID%2 != 1 || streamID <= t.maxStreamID {
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t.mu.Unlock()
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// illegal gRPC stream id.
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errorf("transport: http2Server.HandleStreams received an illegal stream id: %v", streamID)
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return true
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}
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t.maxStreamID = streamID
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t.activeStreams[streamID] = s
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if len(t.activeStreams) == 1 {
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t.idle = time.Time{}
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}
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t.mu.Unlock()
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if channelz.IsOn() {
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atomic.AddInt64(&t.czData.streamsStarted, 1)
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atomic.StoreInt64(&t.czData.lastStreamCreatedTime, time.Now().UnixNano())
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}
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s.requestRead = func(n int) {
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t.adjustWindow(s, uint32(n))
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}
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s.ctx = traceCtx(s.ctx, s.method)
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if t.stats != nil {
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s.ctx = t.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
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inHeader := &stats.InHeader{
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FullMethod: s.method,
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RemoteAddr: t.remoteAddr,
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LocalAddr: t.localAddr,
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Compression: s.recvCompress,
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WireLength: int(frame.Header().Length),
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}
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t.stats.HandleRPC(s.ctx, inHeader)
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}
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s.ctxDone = s.ctx.Done()
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s.wq = newWriteQuota(defaultWriteQuota, s.ctxDone)
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s.trReader = &transportReader{
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reader: &recvBufferReader{
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ctx: s.ctx,
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ctxDone: s.ctxDone,
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recv: s.buf,
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},
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windowHandler: func(n int) {
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t.updateWindow(s, uint32(n))
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},
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}
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// Register the stream with loopy.
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t.controlBuf.put(®isterStream{
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streamID: s.id,
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wq: s.wq,
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})
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handle(s)
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return false
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}
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// HandleStreams receives incoming streams using the given handler. This is
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// typically run in a separate goroutine.
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// traceCtx attaches trace to ctx and returns the new context.
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func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) {
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defer close(t.readerDone)
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for {
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frame, err := t.framer.fr.ReadFrame()
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atomic.StoreUint32(&t.activity, 1)
|
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if err != nil {
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if se, ok := err.(http2.StreamError); ok {
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warningf("transport: http2Server.HandleStreams encountered http2.StreamError: %v", se)
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t.mu.Lock()
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s := t.activeStreams[se.StreamID]
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t.mu.Unlock()
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if s != nil {
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t.closeStream(s, true, se.Code, nil, false)
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} else {
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t.controlBuf.put(&cleanupStream{
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streamID: se.StreamID,
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rst: true,
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rstCode: se.Code,
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onWrite: func() {},
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})
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}
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continue
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}
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if err == io.EOF || err == io.ErrUnexpectedEOF {
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t.Close()
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return
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}
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warningf("transport: http2Server.HandleStreams failed to read frame: %v", err)
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t.Close()
|
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return
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}
|
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switch frame := frame.(type) {
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case *http2.MetaHeadersFrame:
|
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if t.operateHeaders(frame, handle, traceCtx) {
|
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t.Close()
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break
|
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}
|
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case *http2.DataFrame:
|
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t.handleData(frame)
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case *http2.RSTStreamFrame:
|
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t.handleRSTStream(frame)
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case *http2.SettingsFrame:
|
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t.handleSettings(frame)
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case *http2.PingFrame:
|
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t.handlePing(frame)
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case *http2.WindowUpdateFrame:
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t.handleWindowUpdate(frame)
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case *http2.GoAwayFrame:
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// TODO: Handle GoAway from the client appropriately.
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default:
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errorf("transport: http2Server.HandleStreams found unhandled frame type %v.", frame)
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}
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}
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}
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|
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func (t *http2Server) getStream(f http2.Frame) (*Stream, bool) {
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t.mu.Lock()
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defer t.mu.Unlock()
|
|
if t.activeStreams == nil {
|
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// The transport is closing.
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return nil, false
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}
|
|
s, ok := t.activeStreams[f.Header().StreamID]
|
|
if !ok {
|
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// The stream is already done.
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return nil, false
|
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}
|
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return s, true
|
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}
|
|
|
|
// 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 *http2Server) 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 and the transport.
|
|
// Window updates will deliver to the controller for sending when
|
|
// the cumulative quota exceeds the corresponding threshold.
|
|
func (t *http2Server) 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 *http2Server) updateFlowControl(n uint32) {
|
|
t.mu.Lock()
|
|
for _, s := range t.activeStreams {
|
|
s.fc.newLimit(n)
|
|
}
|
|
t.initialWindowSize = int32(n)
|
|
t.mu.Unlock()
|
|
t.controlBuf.put(&outgoingWindowUpdate{
|
|
streamID: 0,
|
|
increment: t.fc.newLimit(n),
|
|
})
|
|
t.controlBuf.put(&outgoingSettings{
|
|
ss: []http2.Setting{
|
|
{
|
|
ID: http2.SettingInitialWindowSize,
|
|
Val: n,
|
|
},
|
|
},
|
|
})
|
|
|
|
}
|
|
|
|
func (t *http2Server) 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, ok := t.getStream(f)
|
|
if !ok {
|
|
return
|
|
}
|
|
if size > 0 {
|
|
if err := s.fc.onData(size); err != nil {
|
|
t.closeStream(s, true, http2.ErrCodeFlowControl, 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 {
|
|
data := make([]byte, len(f.Data()))
|
|
copy(data, f.Data())
|
|
s.write(recvMsg{data: data})
|
|
}
|
|
}
|
|
if f.Header().Flags.Has(http2.FlagDataEndStream) {
|
|
// Received the end of stream from the client.
|
|
s.compareAndSwapState(streamActive, streamReadDone)
|
|
s.write(recvMsg{err: io.EOF})
|
|
}
|
|
}
|
|
|
|
func (t *http2Server) handleRSTStream(f *http2.RSTStreamFrame) {
|
|
s, ok := t.getStream(f)
|
|
if !ok {
|
|
return
|
|
}
|
|
t.closeStream(s, false, 0, nil, false)
|
|
}
|
|
|
|
func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
|
|
if f.IsAck() {
|
|
return
|
|
}
|
|
var ss []http2.Setting
|
|
var updateFuncs []func()
|
|
f.ForeachSetting(func(s http2.Setting) error {
|
|
switch s.ID {
|
|
case http2.SettingMaxHeaderListSize:
|
|
updateFuncs = append(updateFuncs, func() {
|
|
t.maxSendHeaderListSize = new(uint32)
|
|
*t.maxSendHeaderListSize = s.Val
|
|
})
|
|
default:
|
|
ss = append(ss, s)
|
|
}
|
|
return nil
|
|
})
|
|
t.controlBuf.executeAndPut(func(interface{}) bool {
|
|
for _, f := range updateFuncs {
|
|
f()
|
|
}
|
|
return true
|
|
}, &incomingSettings{
|
|
ss: ss,
|
|
})
|
|
}
|
|
|
|
const (
|
|
maxPingStrikes = 2
|
|
defaultPingTimeout = 2 * time.Hour
|
|
)
|
|
|
|
func (t *http2Server) handlePing(f *http2.PingFrame) {
|
|
if f.IsAck() {
|
|
if f.Data == goAwayPing.data && t.drainChan != nil {
|
|
close(t.drainChan)
|
|
return
|
|
}
|
|
// 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)
|
|
|
|
now := time.Now()
|
|
defer func() {
|
|
t.lastPingAt = now
|
|
}()
|
|
// A reset ping strikes means that we don't need to check for policy
|
|
// violation for this ping and the pingStrikes counter should be set
|
|
// to 0.
|
|
if atomic.CompareAndSwapUint32(&t.resetPingStrikes, 1, 0) {
|
|
t.pingStrikes = 0
|
|
return
|
|
}
|
|
t.mu.Lock()
|
|
ns := len(t.activeStreams)
|
|
t.mu.Unlock()
|
|
if ns < 1 && !t.kep.PermitWithoutStream {
|
|
// Keepalive shouldn't be active thus, this new ping should
|
|
// have come after at least defaultPingTimeout.
|
|
if t.lastPingAt.Add(defaultPingTimeout).After(now) {
|
|
t.pingStrikes++
|
|
}
|
|
} else {
|
|
// Check if keepalive policy is respected.
|
|
if t.lastPingAt.Add(t.kep.MinTime).After(now) {
|
|
t.pingStrikes++
|
|
}
|
|
}
|
|
|
|
if t.pingStrikes > maxPingStrikes {
|
|
// Send goaway and close the connection.
|
|
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})
|
|
}
|
|
}
|
|
|
|
func (t *http2Server) handleWindowUpdate(f *http2.WindowUpdateFrame) {
|
|
t.controlBuf.put(&incomingWindowUpdate{
|
|
streamID: f.Header().StreamID,
|
|
increment: f.Increment,
|
|
})
|
|
}
|
|
|
|
func appendHeaderFieldsFromMD(headerFields []hpack.HeaderField, md metadata.MD) []hpack.HeaderField {
|
|
for k, vv := range md {
|
|
if isReservedHeader(k) {
|
|
// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
|
|
continue
|
|
}
|
|
for _, v := range vv {
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
|
|
}
|
|
}
|
|
return headerFields
|
|
}
|
|
|
|
func (t *http2Server) checkForHeaderListSize(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) {
|
|
errorf("header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
// WriteHeader sends the header metedata md back to the client.
|
|
func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
|
|
if s.updateHeaderSent() || s.getState() == streamDone {
|
|
return ErrIllegalHeaderWrite
|
|
}
|
|
s.hdrMu.Lock()
|
|
if md.Len() > 0 {
|
|
if s.header.Len() > 0 {
|
|
s.header = metadata.Join(s.header, md)
|
|
} else {
|
|
s.header = md
|
|
}
|
|
}
|
|
if err := t.writeHeaderLocked(s); err != nil {
|
|
s.hdrMu.Unlock()
|
|
return err
|
|
}
|
|
s.hdrMu.Unlock()
|
|
return nil
|
|
}
|
|
|
|
func (t *http2Server) writeHeaderLocked(s *Stream) error {
|
|
// 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.
|
|
headerFields := make([]hpack.HeaderField, 0, 2) // at least :status, content-type will be there if none else.
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: ":status", Value: "200"})
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: contentType(s.contentSubtype)})
|
|
if s.sendCompress != "" {
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress})
|
|
}
|
|
headerFields = appendHeaderFieldsFromMD(headerFields, s.header)
|
|
success, err := t.controlBuf.executeAndPut(t.checkForHeaderListSize, &headerFrame{
|
|
streamID: s.id,
|
|
hf: headerFields,
|
|
endStream: false,
|
|
onWrite: func() {
|
|
atomic.StoreUint32(&t.resetPingStrikes, 1)
|
|
},
|
|
})
|
|
if !success {
|
|
if err != nil {
|
|
return err
|
|
}
|
|
t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
|
|
return ErrHeaderListSizeLimitViolation
|
|
}
|
|
if t.stats != nil {
|
|
// Note: WireLength is not set in outHeader.
|
|
// TODO(mmukhi): Revisit this later, if needed.
|
|
outHeader := &stats.OutHeader{}
|
|
t.stats.HandleRPC(s.Context(), outHeader)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// WriteStatus sends stream status to the client and terminates the stream.
|
|
// There is no further I/O operations being able to perform on this stream.
|
|
// TODO(zhaoq): Now it indicates the end of entire stream. Revisit if early
|
|
// OK is adopted.
|
|
func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
|
|
if s.getState() == streamDone {
|
|
return nil
|
|
}
|
|
s.hdrMu.Lock()
|
|
// 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.
|
|
headerFields := make([]hpack.HeaderField, 0, 2) // grpc-status and grpc-message will be there if none else.
|
|
if !s.updateHeaderSent() { // No headers have been sent.
|
|
if len(s.header) > 0 { // Send a separate header frame.
|
|
if err := t.writeHeaderLocked(s); err != nil {
|
|
s.hdrMu.Unlock()
|
|
return err
|
|
}
|
|
} else { // Send a trailer only response.
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: ":status", Value: "200"})
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: contentType(s.contentSubtype)})
|
|
}
|
|
}
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status", Value: strconv.Itoa(int(st.Code()))})
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
|
|
|
|
if p := st.Proto(); p != nil && len(p.Details) > 0 {
|
|
stBytes, err := proto.Marshal(p)
|
|
if err != nil {
|
|
// TODO: return error instead, when callers are able to handle it.
|
|
grpclog.Errorf("transport: failed to marshal rpc status: %v, error: %v", p, err)
|
|
} else {
|
|
headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status-details-bin", Value: encodeBinHeader(stBytes)})
|
|
}
|
|
}
|
|
|
|
// Attach the trailer metadata.
|
|
headerFields = appendHeaderFieldsFromMD(headerFields, s.trailer)
|
|
trailingHeader := &headerFrame{
|
|
streamID: s.id,
|
|
hf: headerFields,
|
|
endStream: true,
|
|
onWrite: func() {
|
|
atomic.StoreUint32(&t.resetPingStrikes, 1)
|
|
},
|
|
}
|
|
s.hdrMu.Unlock()
|
|
success, err := t.controlBuf.execute(t.checkForHeaderListSize, trailingHeader)
|
|
if !success {
|
|
if err != nil {
|
|
return err
|
|
}
|
|
t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
|
|
return ErrHeaderListSizeLimitViolation
|
|
}
|
|
t.closeStream(s, false, 0, trailingHeader, true)
|
|
if t.stats != nil {
|
|
t.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Write converts the data into HTTP2 data frame and sends it out. Non-nil error
|
|
// is returns if it fails (e.g., framing error, transport error).
|
|
func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) error {
|
|
if !s.isHeaderSent() { // Headers haven't been written yet.
|
|
if err := t.WriteHeader(s, nil); err != nil {
|
|
// TODO(mmukhi, dfawley): Make sure this is the right code to return.
|
|
return status.Errorf(codes.Internal, "transport: %v", err)
|
|
}
|
|
} else {
|
|
// Writing headers checks for this condition.
|
|
if s.getState() == streamDone {
|
|
// TODO(mmukhi, dfawley): Should the server write also return io.EOF?
|
|
s.cancel()
|
|
select {
|
|
case <-t.ctx.Done():
|
|
return ErrConnClosing
|
|
default:
|
|
}
|
|
return ContextErr(s.ctx.Err())
|
|
}
|
|
}
|
|
// Add some data to header frame so that we can equally distribute bytes across frames.
|
|
emptyLen := http2MaxFrameLen - len(hdr)
|
|
if emptyLen > len(data) {
|
|
emptyLen = len(data)
|
|
}
|
|
hdr = append(hdr, data[:emptyLen]...)
|
|
data = data[emptyLen:]
|
|
df := &dataFrame{
|
|
streamID: s.id,
|
|
h: hdr,
|
|
d: data,
|
|
onEachWrite: func() {
|
|
atomic.StoreUint32(&t.resetPingStrikes, 1)
|
|
},
|
|
}
|
|
if err := s.wq.get(int32(len(hdr) + len(data))); err != nil {
|
|
select {
|
|
case <-t.ctx.Done():
|
|
return ErrConnClosing
|
|
default:
|
|
}
|
|
return ContextErr(s.ctx.Err())
|
|
}
|
|
return t.controlBuf.put(df)
|
|
}
|
|
|
|
// keepalive running in a separate goroutine does the following:
|
|
// 1. Gracefully closes an idle connection after a duration of keepalive.MaxConnectionIdle.
|
|
// 2. Gracefully closes any connection after a duration of keepalive.MaxConnectionAge.
|
|
// 3. Forcibly closes a connection after an additive period of keepalive.MaxConnectionAgeGrace over keepalive.MaxConnectionAge.
|
|
// 4. Makes sure a connection is alive by sending pings with a frequency of keepalive.Time and closes a non-responsive connection
|
|
// after an additional duration of keepalive.Timeout.
|
|
func (t *http2Server) keepalive() {
|
|
p := &ping{}
|
|
var pingSent bool
|
|
maxIdle := time.NewTimer(t.kp.MaxConnectionIdle)
|
|
maxAge := time.NewTimer(t.kp.MaxConnectionAge)
|
|
keepalive := time.NewTimer(t.kp.Time)
|
|
// NOTE: All exit paths of this function should reset their
|
|
// respective timers. A failure to do so will cause the
|
|
// following clean-up to deadlock and eventually leak.
|
|
defer func() {
|
|
if !maxIdle.Stop() {
|
|
<-maxIdle.C
|
|
}
|
|
if !maxAge.Stop() {
|
|
<-maxAge.C
|
|
}
|
|
if !keepalive.Stop() {
|
|
<-keepalive.C
|
|
}
|
|
}()
|
|
for {
|
|
select {
|
|
case <-maxIdle.C:
|
|
t.mu.Lock()
|
|
idle := t.idle
|
|
if idle.IsZero() { // The connection is non-idle.
|
|
t.mu.Unlock()
|
|
maxIdle.Reset(t.kp.MaxConnectionIdle)
|
|
continue
|
|
}
|
|
val := t.kp.MaxConnectionIdle - time.Since(idle)
|
|
t.mu.Unlock()
|
|
if val <= 0 {
|
|
// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
|
|
// Gracefully close the connection.
|
|
t.drain(http2.ErrCodeNo, []byte{})
|
|
// Resetting the timer so that the clean-up doesn't deadlock.
|
|
maxIdle.Reset(infinity)
|
|
return
|
|
}
|
|
maxIdle.Reset(val)
|
|
case <-maxAge.C:
|
|
t.drain(http2.ErrCodeNo, []byte{})
|
|
maxAge.Reset(t.kp.MaxConnectionAgeGrace)
|
|
select {
|
|
case <-maxAge.C:
|
|
// Close the connection after grace period.
|
|
t.Close()
|
|
// Resetting the timer so that the clean-up doesn't deadlock.
|
|
maxAge.Reset(infinity)
|
|
case <-t.ctx.Done():
|
|
}
|
|
return
|
|
case <-keepalive.C:
|
|
if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
|
|
pingSent = false
|
|
keepalive.Reset(t.kp.Time)
|
|
continue
|
|
}
|
|
if pingSent {
|
|
t.Close()
|
|
// Resetting the timer so that the clean-up doesn't deadlock.
|
|
keepalive.Reset(infinity)
|
|
return
|
|
}
|
|
pingSent = true
|
|
if channelz.IsOn() {
|
|
atomic.AddInt64(&t.czData.kpCount, 1)
|
|
}
|
|
t.controlBuf.put(p)
|
|
keepalive.Reset(t.kp.Timeout)
|
|
case <-t.ctx.Done():
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
// 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() error {
|
|
t.mu.Lock()
|
|
if t.state == closing {
|
|
t.mu.Unlock()
|
|
return errors.New("transport: Close() was already called")
|
|
}
|
|
t.state = closing
|
|
streams := t.activeStreams
|
|
t.activeStreams = nil
|
|
t.mu.Unlock()
|
|
t.controlBuf.finish()
|
|
t.cancel()
|
|
err := t.conn.Close()
|
|
if channelz.IsOn() {
|
|
channelz.RemoveEntry(t.channelzID)
|
|
}
|
|
// Cancel all active streams.
|
|
for _, s := range streams {
|
|
s.cancel()
|
|
}
|
|
if t.stats != nil {
|
|
connEnd := &stats.ConnEnd{}
|
|
t.stats.HandleConn(t.ctx, connEnd)
|
|
}
|
|
return err
|
|
}
|
|
|
|
// closeStream clears the footprint of a stream when the stream is not needed
|
|
// any more.
|
|
func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
|
|
if s.swapState(streamDone) == streamDone {
|
|
// If the stream was already done, return.
|
|
return
|
|
}
|
|
// In case stream sending and receiving are invoked in separate
|
|
// goroutines (e.g., bi-directional streaming), cancel needs to be
|
|
// called to interrupt the potential blocking on other goroutines.
|
|
s.cancel()
|
|
cleanup := &cleanupStream{
|
|
streamID: s.id,
|
|
rst: rst,
|
|
rstCode: rstCode,
|
|
onWrite: func() {
|
|
t.mu.Lock()
|
|
if t.activeStreams != nil {
|
|
delete(t.activeStreams, s.id)
|
|
if len(t.activeStreams) == 0 {
|
|
t.idle = time.Now()
|
|
}
|
|
}
|
|
t.mu.Unlock()
|
|
if channelz.IsOn() {
|
|
if eosReceived {
|
|
atomic.AddInt64(&t.czData.streamsSucceeded, 1)
|
|
} else {
|
|
atomic.AddInt64(&t.czData.streamsFailed, 1)
|
|
}
|
|
}
|
|
},
|
|
}
|
|
if hdr != nil {
|
|
hdr.cleanup = cleanup
|
|
t.controlBuf.put(hdr)
|
|
} else {
|
|
t.controlBuf.put(cleanup)
|
|
}
|
|
}
|
|
|
|
func (t *http2Server) RemoteAddr() net.Addr {
|
|
return t.remoteAddr
|
|
}
|
|
|
|
func (t *http2Server) Drain() {
|
|
t.drain(http2.ErrCodeNo, []byte{})
|
|
}
|
|
|
|
func (t *http2Server) drain(code http2.ErrCode, debugData []byte) {
|
|
t.mu.Lock()
|
|
defer t.mu.Unlock()
|
|
if t.drainChan != nil {
|
|
return
|
|
}
|
|
t.drainChan = make(chan struct{})
|
|
t.controlBuf.put(&goAway{code: code, debugData: debugData, headsUp: true})
|
|
}
|
|
|
|
var goAwayPing = &ping{data: [8]byte{1, 6, 1, 8, 0, 3, 3, 9}}
|
|
|
|
// Handles outgoing GoAway and returns true if loopy needs to put itself
|
|
// in draining mode.
|
|
func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
|
|
t.mu.Lock()
|
|
if t.state == closing { // TODO(mmukhi): This seems unnecessary.
|
|
t.mu.Unlock()
|
|
// The transport is closing.
|
|
return false, ErrConnClosing
|
|
}
|
|
sid := t.maxStreamID
|
|
if !g.headsUp {
|
|
// Stop accepting more streams now.
|
|
t.state = draining
|
|
if len(t.activeStreams) == 0 {
|
|
g.closeConn = true
|
|
}
|
|
t.mu.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")
|
|
}
|
|
return true, nil
|
|
}
|
|
t.mu.Unlock()
|
|
// For a graceful close, send out a GoAway with stream ID of MaxUInt32,
|
|
// Follow that with a ping and wait for the ack to come back or a timer
|
|
// to expire. During this time accept new streams since they might have
|
|
// 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 {
|
|
return false, err
|
|
}
|
|
if err := t.framer.fr.WritePing(false, goAwayPing.data); err != nil {
|
|
return false, err
|
|
}
|
|
go func() {
|
|
timer := time.NewTimer(time.Minute)
|
|
defer timer.Stop()
|
|
select {
|
|
case <-t.drainChan:
|
|
case <-timer.C:
|
|
case <-t.ctx.Done():
|
|
return
|
|
}
|
|
t.controlBuf.put(&goAway{code: g.code, debugData: g.debugData})
|
|
}()
|
|
return false, nil
|
|
}
|
|
|
|
func (t *http2Server) 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),
|
|
LastRemoteStreamCreatedTimestamp: 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 *http2Server) IncrMsgSent() {
|
|
atomic.AddInt64(&t.czData.msgSent, 1)
|
|
atomic.StoreInt64(&t.czData.lastMsgSentTime, time.Now().UnixNano())
|
|
}
|
|
|
|
func (t *http2Server) IncrMsgRecv() {
|
|
atomic.AddInt64(&t.czData.msgRecv, 1)
|
|
atomic.StoreInt64(&t.czData.lastMsgRecvTime, time.Now().UnixNano())
|
|
}
|
|
|
|
func (t *http2Server) getOutFlowWindow() int64 {
|
|
resp := make(chan uint32)
|
|
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
|
|
}
|
|
}
|
|
|
|
func getJitter(v time.Duration) time.Duration {
|
|
if v == infinity {
|
|
return 0
|
|
}
|
|
// Generate a jitter between +/- 10% of the value.
|
|
r := int64(v / 10)
|
|
j := grpcrand.Int63n(2*r) - r
|
|
return time.Duration(j)
|
|
}
|