diff options
Diffstat (limited to 'vendor/golang.org/x/net/http2/server.go')
| -rw-r--r-- | vendor/golang.org/x/net/http2/server.go | 1006 |
1 files changed, 709 insertions, 297 deletions
diff --git a/vendor/golang.org/x/net/http2/server.go b/vendor/golang.org/x/net/http2/server.go index 8206fa79d..0b6b4b08d 100644 --- a/vendor/golang.org/x/net/http2/server.go +++ b/vendor/golang.org/x/net/http2/server.go @@ -2,17 +2,6 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// TODO: replace all <-sc.doneServing with reads from the stream's cw -// instead, and make sure that on close we close all open -// streams. then remove doneServing? - -// TODO: re-audit GOAWAY support. Consider each incoming frame type and -// whether it should be ignored during graceful shutdown. - -// TODO: disconnect idle clients. GFE seems to do 4 minutes. make -// configurable? or maximum number of idle clients and remove the -// oldest? - // TODO: turn off the serve goroutine when idle, so // an idle conn only has the readFrames goroutine active. (which could // also be optimized probably to pin less memory in crypto/tls). This @@ -44,6 +33,7 @@ import ( "fmt" "io" "log" + "math" "net" "net/http" "net/textproto" @@ -114,6 +104,15 @@ type Server struct { // PermitProhibitedCipherSuites, if true, permits the use of // cipher suites prohibited by the HTTP/2 spec. PermitProhibitedCipherSuites bool + + // IdleTimeout specifies how long until idle clients should be + // closed with a GOAWAY frame. PING frames are not considered + // activity for the purposes of IdleTimeout. + IdleTimeout time.Duration + + // NewWriteScheduler constructs a write scheduler for a connection. + // If nil, a default scheduler is chosen. + NewWriteScheduler func() WriteScheduler } func (s *Server) maxReadFrameSize() uint32 { @@ -136,9 +135,15 @@ func (s *Server) maxConcurrentStreams() uint32 { // // ConfigureServer must be called before s begins serving. func ConfigureServer(s *http.Server, conf *Server) error { + if s == nil { + panic("nil *http.Server") + } if conf == nil { conf = new(Server) } + if err := configureServer18(s, conf); err != nil { + return err + } if s.TLSConfig == nil { s.TLSConfig = new(tls.Config) @@ -183,9 +188,6 @@ func ConfigureServer(s *http.Server, conf *Server) error { if !haveNPN { s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, NextProtoTLS) } - // h2-14 is temporary (as of 2015-03-05) while we wait for all browsers - // to switch to "h2". - s.TLSConfig.NextProtos = append(s.TLSConfig.NextProtos, "h2-14") if s.TLSNextProto == nil { s.TLSNextProto = map[string]func(*http.Server, *tls.Conn, http.Handler){} @@ -200,7 +202,6 @@ func ConfigureServer(s *http.Server, conf *Server) error { }) } s.TLSNextProto[NextProtoTLS] = protoHandler - s.TLSNextProto["h2-14"] = protoHandler // temporary; see above. return nil } @@ -254,29 +255,35 @@ func (s *Server) ServeConn(c net.Conn, opts *ServeConnOpts) { defer cancel() sc := &serverConn{ - srv: s, - hs: opts.baseConfig(), - conn: c, - baseCtx: baseCtx, - remoteAddrStr: c.RemoteAddr().String(), - bw: newBufferedWriter(c), - handler: opts.handler(), - streams: make(map[uint32]*stream), - readFrameCh: make(chan readFrameResult), - wantWriteFrameCh: make(chan frameWriteMsg, 8), - wroteFrameCh: make(chan frameWriteResult, 1), // buffered; one send in writeFrameAsync - bodyReadCh: make(chan bodyReadMsg), // buffering doesn't matter either way - doneServing: make(chan struct{}), - advMaxStreams: s.maxConcurrentStreams(), - writeSched: writeScheduler{ - maxFrameSize: initialMaxFrameSize, - }, + srv: s, + hs: opts.baseConfig(), + conn: c, + baseCtx: baseCtx, + remoteAddrStr: c.RemoteAddr().String(), + bw: newBufferedWriter(c), + handler: opts.handler(), + streams: make(map[uint32]*stream), + readFrameCh: make(chan readFrameResult), + wantWriteFrameCh: make(chan FrameWriteRequest, 8), + wantStartPushCh: make(chan startPushRequest, 8), + wroteFrameCh: make(chan frameWriteResult, 1), // buffered; one send in writeFrameAsync + bodyReadCh: make(chan bodyReadMsg), // buffering doesn't matter either way + doneServing: make(chan struct{}), + clientMaxStreams: math.MaxUint32, // Section 6.5.2: "Initially, there is no limit to this value" + advMaxStreams: s.maxConcurrentStreams(), initialWindowSize: initialWindowSize, + maxFrameSize: initialMaxFrameSize, headerTableSize: initialHeaderTableSize, serveG: newGoroutineLock(), pushEnabled: true, } + if s.NewWriteScheduler != nil { + sc.writeSched = s.NewWriteScheduler() + } else { + sc.writeSched = NewRandomWriteScheduler() + } + sc.flow.add(initialWindowSize) sc.inflow.add(initialWindowSize) sc.hpackEncoder = hpack.NewEncoder(&sc.headerWriteBuf) @@ -356,16 +363,18 @@ type serverConn struct { handler http.Handler baseCtx contextContext framer *Framer - doneServing chan struct{} // closed when serverConn.serve ends - readFrameCh chan readFrameResult // written by serverConn.readFrames - wantWriteFrameCh chan frameWriteMsg // from handlers -> serve - wroteFrameCh chan frameWriteResult // from writeFrameAsync -> serve, tickles more frame writes - bodyReadCh chan bodyReadMsg // from handlers -> serve - testHookCh chan func(int) // code to run on the serve loop - flow flow // conn-wide (not stream-specific) outbound flow control - inflow flow // conn-wide inbound flow control - tlsState *tls.ConnectionState // shared by all handlers, like net/http + doneServing chan struct{} // closed when serverConn.serve ends + readFrameCh chan readFrameResult // written by serverConn.readFrames + wantWriteFrameCh chan FrameWriteRequest // from handlers -> serve + wantStartPushCh chan startPushRequest // from handlers -> serve + wroteFrameCh chan frameWriteResult // from writeFrameAsync -> serve, tickles more frame writes + bodyReadCh chan bodyReadMsg // from handlers -> serve + testHookCh chan func(int) // code to run on the serve loop + flow flow // conn-wide (not stream-specific) outbound flow control + inflow flow // conn-wide inbound flow control + tlsState *tls.ConnectionState // shared by all handlers, like net/http remoteAddrStr string + writeSched WriteScheduler // Everything following is owned by the serve loop; use serveG.check(): serveG goroutineLock // used to verify funcs are on serve() @@ -375,22 +384,27 @@ type serverConn struct { unackedSettings int // how many SETTINGS have we sent without ACKs? clientMaxStreams uint32 // SETTINGS_MAX_CONCURRENT_STREAMS from client (our PUSH_PROMISE limit) advMaxStreams uint32 // our SETTINGS_MAX_CONCURRENT_STREAMS advertised the client - curOpenStreams uint32 // client's number of open streams - maxStreamID uint32 // max ever seen + curClientStreams uint32 // number of open streams initiated by the client + curPushedStreams uint32 // number of open streams initiated by server push + maxClientStreamID uint32 // max ever seen from client (odd), or 0 if there have been no client requests + maxPushPromiseID uint32 // ID of the last push promise (even), or 0 if there have been no pushes streams map[uint32]*stream initialWindowSize int32 + maxFrameSize int32 headerTableSize uint32 peerMaxHeaderListSize uint32 // zero means unknown (default) canonHeader map[string]string // http2-lower-case -> Go-Canonical-Case - writingFrame bool // started write goroutine but haven't heard back on wroteFrameCh + writingFrame bool // started writing a frame (on serve goroutine or separate) + writingFrameAsync bool // started a frame on its own goroutine but haven't heard back on wroteFrameCh needsFrameFlush bool // last frame write wasn't a flush - writeSched writeScheduler - inGoAway bool // we've started to or sent GOAWAY - needToSendGoAway bool // we need to schedule a GOAWAY frame write + inGoAway bool // we've started to or sent GOAWAY + inFrameScheduleLoop bool // whether we're in the scheduleFrameWrite loop + needToSendGoAway bool // we need to schedule a GOAWAY frame write goAwayCode ErrCode shutdownTimerCh <-chan time.Time // nil until used shutdownTimer *time.Timer // nil until used - freeRequestBodyBuf []byte // if non-nil, a free initialWindowSize buffer for getRequestBodyBuf + idleTimer *time.Timer // nil if unused + idleTimerCh <-chan time.Time // nil if unused // Owned by the writeFrameAsync goroutine: headerWriteBuf bytes.Buffer @@ -434,11 +448,11 @@ type stream struct { numTrailerValues int64 weight uint8 state streamState - sentReset bool // only true once detached from streams map - gotReset bool // only true once detacted from streams map - gotTrailerHeader bool // HEADER frame for trailers was seen - wroteHeaders bool // whether we wrote headers (not status 100) - reqBuf []byte + sentReset bool // only true once detached from streams map + gotReset bool // only true once detacted from streams map + gotTrailerHeader bool // HEADER frame for trailers was seen + wroteHeaders bool // whether we wrote headers (not status 100) + reqBuf []byte // if non-nil, body pipe buffer to return later at EOF trailer http.Header // accumulated trailers reqTrailer http.Header // handler's Request.Trailer @@ -453,7 +467,7 @@ func (sc *serverConn) HeaderEncoder() (*hpack.Encoder, *bytes.Buffer) { func (sc *serverConn) state(streamID uint32) (streamState, *stream) { sc.serveG.check() - // http://http2.github.io/http2-spec/#rfc.section.5.1 + // http://tools.ietf.org/html/rfc7540#section-5.1 if st, ok := sc.streams[streamID]; ok { return st.state, st } @@ -463,8 +477,14 @@ func (sc *serverConn) state(streamID uint32) (streamState, *stream) { // a client sends a HEADERS frame on stream 7 without ever sending a // frame on stream 5, then stream 5 transitions to the "closed" // state when the first frame for stream 7 is sent or received." - if streamID <= sc.maxStreamID { - return stateClosed, nil + if streamID%2 == 1 { + if streamID <= sc.maxClientStreamID { + return stateClosed, nil + } + } else { + if streamID <= sc.maxPushPromiseID { + return stateClosed, nil + } } return stateIdle, nil } @@ -603,17 +623,17 @@ func (sc *serverConn) readFrames() { // frameWriteResult is the message passed from writeFrameAsync to the serve goroutine. type frameWriteResult struct { - wm frameWriteMsg // what was written (or attempted) - err error // result of the writeFrame call + wr FrameWriteRequest // what was written (or attempted) + err error // result of the writeFrame call } // writeFrameAsync runs in its own goroutine and writes a single frame // and then reports when it's done. // At most one goroutine can be running writeFrameAsync at a time per // serverConn. -func (sc *serverConn) writeFrameAsync(wm frameWriteMsg) { - err := wm.write.writeFrame(sc) - sc.wroteFrameCh <- frameWriteResult{wm, err} +func (sc *serverConn) writeFrameAsync(wr FrameWriteRequest) { + err := wr.write.writeFrame(sc) + sc.wroteFrameCh <- frameWriteResult{wr, err} } func (sc *serverConn) closeAllStreamsOnConnClose() { @@ -657,7 +677,7 @@ func (sc *serverConn) serve() { sc.vlogf("http2: server connection from %v on %p", sc.conn.RemoteAddr(), sc.hs) } - sc.writeFrame(frameWriteMsg{ + sc.writeFrame(FrameWriteRequest{ write: writeSettings{ {SettingMaxFrameSize, sc.srv.maxReadFrameSize()}, {SettingMaxConcurrentStreams, sc.advMaxStreams}, @@ -682,6 +702,17 @@ func (sc *serverConn) serve() { sc.setConnState(http.StateActive) sc.setConnState(http.StateIdle) + if sc.srv.IdleTimeout != 0 { + sc.idleTimer = time.NewTimer(sc.srv.IdleTimeout) + defer sc.idleTimer.Stop() + sc.idleTimerCh = sc.idleTimer.C + } + + var gracefulShutdownCh <-chan struct{} + if sc.hs != nil { + gracefulShutdownCh = h1ServerShutdownChan(sc.hs) + } + go sc.readFrames() // closed by defer sc.conn.Close above settingsTimer := time.NewTimer(firstSettingsTimeout) @@ -689,8 +720,10 @@ func (sc *serverConn) serve() { for { loopNum++ select { - case wm := <-sc.wantWriteFrameCh: - sc.writeFrame(wm) + case wr := <-sc.wantWriteFrameCh: + sc.writeFrame(wr) + case spr := <-sc.wantStartPushCh: + sc.startPush(spr) case res := <-sc.wroteFrameCh: sc.wroteFrame(res) case res := <-sc.readFrameCh: @@ -707,12 +740,22 @@ func (sc *serverConn) serve() { case <-settingsTimer.C: sc.logf("timeout waiting for SETTINGS frames from %v", sc.conn.RemoteAddr()) return + case <-gracefulShutdownCh: + gracefulShutdownCh = nil + sc.startGracefulShutdown() case <-sc.shutdownTimerCh: sc.vlogf("GOAWAY close timer fired; closing conn from %v", sc.conn.RemoteAddr()) return + case <-sc.idleTimerCh: + sc.vlogf("connection is idle") + sc.goAway(ErrCodeNo) case fn := <-sc.testHookCh: fn(loopNum) } + + if sc.inGoAway && sc.curClientStreams == 0 && !sc.needToSendGoAway && !sc.writingFrame { + return + } } } @@ -760,7 +803,7 @@ func (sc *serverConn) writeDataFromHandler(stream *stream, data []byte, endStrea ch := errChanPool.Get().(chan error) writeArg := writeDataPool.Get().(*writeData) *writeArg = writeData{stream.id, data, endStream} - err := sc.writeFrameFromHandler(frameWriteMsg{ + err := sc.writeFrameFromHandler(FrameWriteRequest{ write: writeArg, stream: stream, done: ch, @@ -796,17 +839,17 @@ func (sc *serverConn) writeDataFromHandler(stream *stream, data []byte, endStrea return err } -// writeFrameFromHandler sends wm to sc.wantWriteFrameCh, but aborts +// writeFrameFromHandler sends wr to sc.wantWriteFrameCh, but aborts // if the connection has gone away. // // This must not be run from the serve goroutine itself, else it might // deadlock writing to sc.wantWriteFrameCh (which is only mildly // buffered and is read by serve itself). If you're on the serve // goroutine, call writeFrame instead. -func (sc *serverConn) writeFrameFromHandler(wm frameWriteMsg) error { +func (sc *serverConn) writeFrameFromHandler(wr FrameWriteRequest) error { sc.serveG.checkNotOn() // NOT select { - case sc.wantWriteFrameCh <- wm: + case sc.wantWriteFrameCh <- wr: return nil case <-sc.doneServing: // Serve loop is gone. @@ -823,38 +866,38 @@ func (sc *serverConn) writeFrameFromHandler(wm frameWriteMsg) error { // make it onto the wire // // If you're not on the serve goroutine, use writeFrameFromHandler instead. -func (sc *serverConn) writeFrame(wm frameWriteMsg) { +func (sc *serverConn) writeFrame(wr FrameWriteRequest) { sc.serveG.check() var ignoreWrite bool // Don't send a 100-continue response if we've already sent headers. // See golang.org/issue/14030. - switch wm.write.(type) { + switch wr.write.(type) { case *writeResHeaders: - wm.stream.wroteHeaders = true + wr.stream.wroteHeaders = true case write100ContinueHeadersFrame: - if wm.stream.wroteHeaders { + if wr.stream.wroteHeaders { ignoreWrite = true } } if !ignoreWrite { - sc.writeSched.add(wm) + sc.writeSched.Push(wr) } sc.scheduleFrameWrite() } -// startFrameWrite starts a goroutine to write wm (in a separate +// startFrameWrite starts a goroutine to write wr (in a separate // goroutine since that might block on the network), and updates the -// serve goroutine's state about the world, updated from info in wm. -func (sc *serverConn) startFrameWrite(wm frameWriteMsg) { +// serve goroutine's state about the world, updated from info in wr. +func (sc *serverConn) startFrameWrite(wr FrameWriteRequest) { sc.serveG.check() if sc.writingFrame { panic("internal error: can only be writing one frame at a time") } - st := wm.stream + st := wr.stream if st != nil { switch st.state { case stateHalfClosedLocal: @@ -865,13 +908,31 @@ func (sc *serverConn) startFrameWrite(wm frameWriteMsg) { sc.scheduleFrameWrite() return } - panic(fmt.Sprintf("internal error: attempt to send a write %v on a closed stream", wm)) + panic(fmt.Sprintf("internal error: attempt to send a write %v on a closed stream", wr)) + } + } + if wpp, ok := wr.write.(*writePushPromise); ok { + var err error + wpp.promisedID, err = wpp.allocatePromisedID() + if err != nil { + sc.writingFrameAsync = false + if wr.done != nil { + wr.done <- err + } + return } } sc.writingFrame = true sc.needsFrameFlush = true - go sc.writeFrameAsync(wm) + if wr.write.staysWithinBuffer(sc.bw.Available()) { + sc.writingFrameAsync = false + err := wr.write.writeFrame(sc) + sc.wroteFrame(frameWriteResult{wr, err}) + } else { + sc.writingFrameAsync = true + go sc.writeFrameAsync(wr) + } } // errHandlerPanicked is the error given to any callers blocked in a read from @@ -887,25 +948,26 @@ func (sc *serverConn) wroteFrame(res frameWriteResult) { panic("internal error: expected to be already writing a frame") } sc.writingFrame = false + sc.writingFrameAsync = false - wm := res.wm - st := wm.stream + wr := res.wr + st := wr.stream - closeStream := endsStream(wm.write) + closeStream := endsStream(wr.write) - if _, ok := wm.write.(handlerPanicRST); ok { + if _, ok := wr.write.(handlerPanicRST); ok { sc.closeStream(st, errHandlerPanicked) } // Reply (if requested) to the blocked ServeHTTP goroutine. - if ch := wm.done; ch != nil { + if ch := wr.done; ch != nil { select { case ch <- res.err: default: - panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wm.write)) + panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write)) } } - wm.write = nil // prevent use (assume it's tainted after wm.done send) + wr.write = nil // prevent use (assume it's tainted after wr.done send) if closeStream { if st == nil { @@ -916,11 +978,11 @@ func (sc *serverConn) wroteFrame(res frameWriteResult) { // Here we would go to stateHalfClosedLocal in // theory, but since our handler is done and // the net/http package provides no mechanism - // for finishing writing to a ResponseWriter - // while still reading data (see possible TODO - // at top of this file), we go into closed - // state here anyway, after telling the peer - // we're hanging up on them. + // for closing a ResponseWriter while still + // reading data (see possible TODO at top of + // this file), we go into closed state here + // anyway, after telling the peer we're + // hanging up on them. st.state = stateHalfClosedLocal // won't last long, but necessary for closeStream via resetStream errCancel := streamError(st.id, ErrCodeCancel) sc.resetStream(errCancel) @@ -946,47 +1008,68 @@ func (sc *serverConn) wroteFrame(res frameWriteResult) { // flush the write buffer. func (sc *serverConn) scheduleFrameWrite() { sc.serveG.check() - if sc.writingFrame { - return - } - if sc.needToSendGoAway { - sc.needToSendGoAway = false - sc.startFrameWrite(frameWriteMsg{ - write: &writeGoAway{ - maxStreamID: sc.maxStreamID, - code: sc.goAwayCode, - }, - }) - return - } - if sc.needToSendSettingsAck { - sc.needToSendSettingsAck = false - sc.startFrameWrite(frameWriteMsg{write: writeSettingsAck{}}) + if sc.writingFrame || sc.inFrameScheduleLoop { return } - if !sc.inGoAway { - if wm, ok := sc.writeSched.take(); ok { - sc.startFrameWrite(wm) - return + sc.inFrameScheduleLoop = true + for !sc.writingFrameAsync { + if sc.needToSendGoAway { + sc.needToSendGoAway = false + sc.startFrameWrite(FrameWriteRequest{ + write: &writeGoAway{ + maxStreamID: sc.maxClientStreamID, + code: sc.goAwayCode, + }, + }) + continue } + if sc.needToSendSettingsAck { + sc.needToSendSettingsAck = false + sc.startFrameWrite(FrameWriteRequest{write: writeSettingsAck{}}) + continue + } + if !sc.inGoAway || sc.goAwayCode == ErrCodeNo { + if wr, ok := sc.writeSched.Pop(); ok { + sc.startFrameWrite(wr) + continue + } + } + if sc.needsFrameFlush { + sc.startFrameWrite(FrameWriteRequest{write: flushFrameWriter{}}) + sc.needsFrameFlush = false // after startFrameWrite, since it sets this true + continue + } + break } - if sc.needsFrameFlush { - sc.startFrameWrite(frameWriteMsg{write: flushFrameWriter{}}) - sc.needsFrameFlush = false // after startFrameWrite, since it sets this true - return - } + sc.inFrameScheduleLoop = false +} + +// startGracefulShutdown sends a GOAWAY with ErrCodeNo to tell the +// client we're gracefully shutting down. The connection isn't closed +// until all current streams are done. +func (sc *serverConn) startGracefulShutdown() { + sc.goAwayIn(ErrCodeNo, 0) } func (sc *serverConn) goAway(code ErrCode) { sc.serveG.check() - if sc.inGoAway { - return - } + var forceCloseIn time.Duration if code != ErrCodeNo { - sc.shutDownIn(250 * time.Millisecond) + forceCloseIn = 250 * time.Millisecond } else { // TODO: configurable - sc.shutDownIn(1 * time.Second) + forceCloseIn = 1 * time.Second + } + sc.goAwayIn(code, forceCloseIn) +} + +func (sc *serverConn) goAwayIn(code ErrCode, forceCloseIn time.Duration) { + sc.serveG.check() + if sc.inGoAway { + return + } + if forceCloseIn != 0 { + sc.shutDownIn(forceCloseIn) } sc.inGoAway = true sc.needToSendGoAway = true @@ -1002,7 +1085,7 @@ func (sc *serverConn) shutDownIn(d time.Duration) { func (sc *serverConn) resetStream(se StreamError) { sc.serveG.check() - sc.writeFrame(frameWriteMsg{write: se}) + sc.writeFrame(FrameWriteRequest{write: se}) if st, ok := sc.streams[se.StreamID]; ok { st.sentReset = true sc.closeStream(st, se) @@ -1090,6 +1173,8 @@ func (sc *serverConn) processFrame(f Frame) error { return sc.processResetStream(f) case *PriorityFrame: return sc.processPriority(f) + case *GoAwayFrame: + return sc.processGoAway(f) case *PushPromiseFrame: // A client cannot push. Thus, servers MUST treat the receipt of a PUSH_PROMISE // frame as a connection error (Section 5.4.1) of type PROTOCOL_ERROR. @@ -1115,7 +1200,10 @@ func (sc *serverConn) processPing(f *PingFrame) error { // PROTOCOL_ERROR." return ConnectionError(ErrCodeProtocol) } - sc.writeFrame(frameWriteMsg{write: writePingAck{f}}) + if sc.inGoAway && sc.goAwayCode != ErrCodeNo { + return nil + } + sc.writeFrame(FrameWriteRequest{write: writePingAck{f}}) return nil } @@ -1123,7 +1211,14 @@ func (sc *serverConn) processWindowUpdate(f *WindowUpdateFrame) error { sc.serveG.check() switch { case f.StreamID != 0: // stream-level flow control - st := sc.streams[f.StreamID] + state, st := sc.state(f.StreamID) + if state == stateIdle { + // Section 5.1: "Receiving any frame other than HEADERS + // or PRIORITY on a stream in this state MUST be + // treated as a connection error (Section 5.4.1) of + // type PROTOCOL_ERROR." + return ConnectionError(ErrCodeProtocol) + } if st == nil { // "WINDOW_UPDATE can be sent by a peer that has sent a // frame bearing the END_STREAM flag. This means that a @@ -1170,11 +1265,21 @@ func (sc *serverConn) closeStream(st *stream, err error) { panic(fmt.Sprintf("invariant; can't close stream in state %v", st.state)) } st.state = stateClosed - sc.curOpenStreams-- - if sc.curOpenStreams == 0 { - sc.setConnState(http.StateIdle) + if st.isPushed() { + sc.curPushedStreams-- + } else { + sc.curClientStreams-- } delete(sc.streams, st.id) + if len(sc.streams) == 0 { + sc.setConnState(http.StateIdle) + if sc.srv.IdleTimeout != 0 { + sc.idleTimer.Reset(sc.srv.IdleTimeout) + } + if h1ServerKeepAlivesDisabled(sc.hs) { + sc.startGracefulShutdown() + } + } if p := st.body; p != nil { // Return any buffered unread bytes worth of conn-level flow control. // See golang.org/issue/16481 @@ -1183,19 +1288,7 @@ func (sc *serverConn) closeStream(st *stream, err error) { p.CloseWithError(err) } st.cw.Close() // signals Handler's CloseNotifier, unblocks writes, etc - sc.writeSched.forgetStream(st.id) - if st.reqBuf != nil { - // Stash this request body buffer (64k) away for reuse - // by a future POST/PUT/etc. - // - // TODO(bradfitz): share on the server? sync.Pool? - // Server requires locks and might hurt contention. - // sync.Pool might work, or might be worse, depending - // on goroutine CPU migrations. (get and put on - // separate CPUs). Maybe a mix of strategies. But - // this is an easy win for now. - sc.freeRequestBodyBuf = st.reqBuf - } + sc.writeSched.CloseStream(st.id) } func (sc *serverConn) processSettings(f *SettingsFrame) error { @@ -1237,7 +1330,7 @@ func (sc *serverConn) processSetting(s Setting) error { case SettingInitialWindowSize: return sc.processSettingInitialWindowSize(s.Val) case SettingMaxFrameSize: - sc.writeSched.maxFrameSize = s.Val + sc.maxFrameSize = int32(s.Val) // the maximum valid s.Val is < 2^31 case SettingMaxHeaderListSize: sc.peerMaxHeaderListSize = s.Val default: @@ -1281,14 +1374,24 @@ func (sc *serverConn) processSettingInitialWindowSize(val uint32) error { func (sc *serverConn) processData(f *DataFrame) error { sc.serveG.check() + if sc.inGoAway && sc.goAwayCode != ErrCodeNo { + return nil + } data := f.Data() // "If a DATA frame is received whose stream is not in "open" // or "half closed (local)" state, the recipient MUST respond // with a stream error (Section 5.4.2) of type STREAM_CLOSED." id := f.Header().StreamID - st, ok := sc.streams[id] - if !ok || st.state != stateOpen || st.gotTrailerHeader { + state, st := sc.state(id) + if id == 0 || state == stateIdle { + // Section 5.1: "Receiving any frame other than HEADERS + // or PRIORITY on a stream in this state MUST be + // treated as a connection error (Section 5.4.1) of + // type PROTOCOL_ERROR." + return ConnectionError(ErrCodeProtocol) + } + if st == nil || state != stateOpen || st.gotTrailerHeader { // This includes sending a RST_STREAM if the stream is // in stateHalfClosedLocal (which currently means that // the http.Handler returned, so it's done reading & @@ -1350,6 +1453,25 @@ func (sc *serverConn) processData(f *DataFrame) error { return nil } +func (sc *serverConn) processGoAway(f *GoAwayFrame) error { + sc.serveG.check() + if f.ErrCode != ErrCodeNo { + sc.logf("http2: received GOAWAY %+v, starting graceful shutdown", f) + } else { + sc.vlogf("http2: received GOAWAY %+v, starting graceful shutdown", f) + } + sc.startGracefulShutdown() + // http://tools.ietf.org/html/rfc7540#section-6.8 + // We should not create any new streams, which means we should disable push. + sc.pushEnabled = false + return nil +} + +// isPushed reports whether the stream is server-initiated. +func (st *stream) isPushed() bool { + return st.id%2 == 0 +} + // endStream closes a Request.Body's pipe. It is called when a DATA // frame says a request body is over (or after trailers). func (st *stream) endStream() { @@ -1379,12 +1501,12 @@ func (st *stream) copyTrailersToHandlerRequest() { func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error { sc.serveG.check() - id := f.Header().StreamID + id := f.StreamID if sc.inGoAway { // Ignore. return nil } - // http://http2.github.io/http2-spec/#rfc.section.5.1.1 + // http://tools.ietf.org/html/rfc7540#section-5.1.1 // Streams initiated by a client MUST use odd-numbered stream // identifiers. [...] An endpoint that receives an unexpected // stream identifier MUST respond with a connection error @@ -1396,8 +1518,7 @@ func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error { // send a trailer for an open one. If we already have a stream // open, let it process its own HEADERS frame (trailers at this // point, if it's valid). - st := sc.streams[f.Header().StreamID] - if st != nil { + if st := sc.streams[f.StreamID]; st != nil { return st.processTrailerHeaders(f) } @@ -1406,54 +1527,45 @@ func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error { // endpoint has opened or reserved. [...] An endpoint that // receives an unexpected stream identifier MUST respond with // a connection error (Section 5.4.1) of type PROTOCOL_ERROR. - if id <= sc.maxStreamID { + if id <= sc.maxClientStreamID { return ConnectionError(ErrCodeProtocol) } - sc.maxStreamID = id + sc.maxClientStreamID = id - ctx, cancelCtx := contextWithCancel(sc.baseCtx) - st = &stream{ - sc: sc, - id: id, - state: stateOpen, - ctx: ctx, - cancelCtx: cancelCtx, + if sc.idleTimer != nil { + sc.idleTimer.Stop() } - if f.StreamEnded() { - st.state = stateHalfClosedRemote - } - st.cw.Init() - st.flow.conn = &sc.flow // link to conn-level counter - st.flow.add(sc.initialWindowSize) - st.inflow.conn = &sc.inflow // link to conn-level counter - st.inflow.add(initialWindowSize) // TODO: update this when we send a higher initial window size in the initial settings - - sc.streams[id] = st - if f.HasPriority() { - adjustStreamPriority(sc.streams, st.id, f.Priority) - } - sc.curOpenStreams++ - if sc.curOpenStreams == 1 { - sc.setConnState(http.StateActive) - } - if sc.curOpenStreams > sc.advMaxStreams { - // "Endpoints MUST NOT exceed the limit set by their - // peer. An endpoint that receives a HEADERS frame - // that causes their advertised concurrent stream - // limit to be exceeded MUST treat this as a stream - // error (Section 5.4.2) of type PROTOCOL_ERROR or - // REFUSED_STREAM." + // http://tools.ietf.org/html/rfc7540#section-5.1.2 + // [...] Endpoints MUST NOT exceed the limit set by their peer. An + // endpoint that receives a HEADERS frame that causes their + // advertised concurrent stream limit to be exceeded MUST treat + // this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR + // or REFUSED_STREAM. + if sc.curClientStreams+1 > sc.advMaxStreams { if sc.unackedSettings == 0 { // They should know better. - return streamError(st.id, ErrCodeProtocol) + return streamError(id, ErrCodeProtocol) } // Assume it's a network race, where they just haven't // received our last SETTINGS update. But actually // this can't happen yet, because we don't yet provide // a way for users to adjust server parameters at // runtime. - return streamError(st.id, ErrCodeRefusedStream) + return streamError(id, ErrCodeRefusedStream) + } + + initialState := stateOpen + if f.StreamEnded() { + initialState = stateHalfClosedRemote + } + st := sc.newStream(id, 0, initialState) + + if f.HasPriority() { + if err := checkPriority(f.StreamID, f.Priority); err != nil { + return err + } + sc.writeSched.AdjustStream(st.id, f.Priority) } rw, req, err := sc.newWriterAndRequest(st, f) @@ -1471,10 +1583,21 @@ func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error { if f.Truncated { // Their header list was too long. Send a 431 error. handler = handleHeaderListTooLong - } else if err := checkValidHTTP2Request(req); err != nil { + } else if err := checkValidHTTP2RequestHeaders(req.Header); err != nil { handler = new400Handler(err) } + // The net/http package sets the read deadline from the + // http.Server.ReadTimeout during the TLS handshake, but then + // passes the connection off to us with the deadline already + // set. Disarm it here after the request headers are read, + // similar to how the http1 server works. Here it's + // technically more like the http1 Server's ReadHeaderTimeout + // (in Go 1.8), though. That's a more sane option anyway. + if sc.hs.ReadTimeout != 0 { + sc.conn.SetReadDeadline(time.Time{}) + } + go sc.runHandler(rw, req, handler) return nil } @@ -1509,62 +1632,78 @@ func (st *stream) processTrailerHeaders(f *MetaHeadersFrame) error { return nil } +func checkPriority(streamID uint32, p PriorityParam) error { + if streamID == p.StreamDep { + // Section 5.3.1: "A stream cannot depend on itself. An endpoint MUST treat + // this as a stream error (Section 5.4.2) of type PROTOCOL_ERROR." + // Section 5.3.3 says that a stream can depend on one of its dependencies, + // so it's only self-dependencies that are forbidden. + return streamError(streamID, ErrCodeProtocol) + } + return nil +} + func (sc *serverConn) processPriority(f *PriorityFrame) error { - adjustStreamPriority(sc.streams, f.StreamID, f.PriorityParam) + if sc.inGoAway { + return nil + } + if err := checkPriority(f.StreamID, f.PriorityParam); err != nil { + return err + } + sc.writeSched.AdjustStream(f.StreamID, f.PriorityParam) return nil } -func adjustStreamPriority(streams map[uint32]*stream, streamID uint32, priority PriorityParam) { - st, ok := streams[streamID] - if !ok { - // TODO: not quite correct (this streamID might - // already exist in the dep tree, but be closed), but - // close enough for now. - return +func (sc *serverConn) newStream(id, pusherID uint32, state streamState) *stream { + sc.serveG.check() + if id == 0 { + panic("internal error: cannot create stream with id 0") } - st.weight = priority.Weight - parent := streams[priority.StreamDep] // might be nil - if parent == st { - // if client tries to set this stream to be the parent of itself - // ignore and keep going - return + + ctx, cancelCtx := contextWithCancel(sc.baseCtx) + st := &stream{ + sc: sc, + id: id, + state: state, + ctx: ctx, + cancelCtx: cancelCtx, } + st.cw.Init() + st.flow.conn = &sc.flow // link to conn-level counter + st.flow.add(sc.initialWindowSize) + st.inflow.conn = &sc.inflow // link to conn-level counter + st.inflow.add(initialWindowSize) // TODO: update this when we send a higher initial window size in the initial settings - // section 5.3.3: If a stream is made dependent on one of its - // own dependencies, the formerly dependent stream is first - // moved to be dependent on the reprioritized stream's previous - // parent. The moved dependency retains its weight. - for piter := parent; piter != nil; piter = piter.parent { - if piter == st { - parent.parent = st.parent - break - } + sc.streams[id] = st + sc.writeSched.OpenStream(st.id, OpenStreamOptions{PusherID: pusherID}) + if st.isPushed() { + sc.curPushedStreams++ + } else { + sc.curClientStreams++ } - st.parent = parent - if priority.Exclusive && (st.parent != nil || priority.StreamDep == 0) { - for _, openStream := range streams { - if openStream != st && openStream.parent == st.parent { - openStream.parent = st - } - } + if sc.curClientStreams+sc.curPushedStreams == 1 { + sc.setConnState(http.StateActive) } + + return st } func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*responseWriter, *http.Request, error) { sc.serveG.check() - method := f.PseudoValue("method") - path := f.PseudoValue("path") - scheme := f.PseudoValue("scheme") - authority := f.PseudoValue("authority") + rp := requestParam{ + method: f.PseudoValue("method"), + scheme: f.PseudoValue("scheme"), + authority: f.PseudoValue("authority"), + path: f.PseudoValue("path"), + } - isConnect := method == "CONNECT" + isConnect := rp.method == "CONNECT" if isConnect { - if path != "" || scheme != "" || authority == "" { + if rp.path != "" || rp.scheme != "" || rp.authority == "" { return nil, nil, streamError(f.StreamID, ErrCodeProtocol) } - } else if method == "" || path == "" || - (scheme != "https" && scheme != "http") { + } else if rp.method == "" || rp.path == "" || (rp.scheme != "https" && rp.scheme != "http") { // See 8.1.2.6 Malformed Requests and Responses: // // Malformed requests or responses that are detected @@ -1579,36 +1718,64 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res } bodyOpen := !f.StreamEnded() - if method == "HEAD" && bodyOpen { + if rp.method == "HEAD" && bodyOpen { // HEAD requests can't have bodies return nil, nil, streamError(f.StreamID, ErrCodeProtocol) } - var tlsState *tls.ConnectionState // nil if not scheme https - if scheme == "https" { - tlsState = sc.tlsState + rp.header = make(http.Header) + for _, hf := range f.RegularFields() { + rp.header.Add(sc.canonicalHeader(hf.Name), hf.Value) + } + if rp.authority == "" { + rp.authority = rp.header.Get("Host") } - header := make(http.Header) - for _, hf := range f.RegularFields() { - header.Add(sc.canonicalHeader(hf.Name), hf.Value) + rw, req, err := sc.newWriterAndRequestNoBody(st, rp) + if err != nil { + return nil, nil, err + } + if bodyOpen { + st.reqBuf = getRequestBodyBuf() + req.Body.(*requestBody).pipe = &pipe{ + b: &fixedBuffer{buf: st.reqBuf}, + } + + if vv, ok := rp.header["Content-Length"]; ok { + req.ContentLength, _ = strconv.ParseInt(vv[0], 10, 64) + } else { + req.ContentLength = -1 + } } + return rw, req, nil +} - if authority == "" { - authority = header.Get("Host") +type requestParam struct { + method string + scheme, authority, path string + header http.Header +} + +func (sc *serverConn) newWriterAndRequestNoBody(st *stream, rp requestParam) (*responseWriter, *http.Request, error) { + sc.serveG.check() + + var tlsState *tls.ConnectionState // nil if not scheme https + if rp.scheme == "https" { + tlsState = sc.tlsState } - needsContinue := header.Get("Expect") == "100-continue" + + needsContinue := rp.header.Get("Expect") == "100-continue" if needsContinue { - header.Del("Expect") + rp.header.Del("Expect") } // Merge Cookie headers into one "; "-delimited value. - if cookies := header["Cookie"]; len(cookies) > 1 { - header.Set("Cookie", strings.Join(cookies, "; ")) + if cookies := rp.header["Cookie"]; len(cookies) > 1 { + rp.header.Set("Cookie", strings.Join(cookies, "; ")) } // Setup Trailers var trailer http.Header - for _, v := range header["Trailer"] { + for _, v := range rp.header["Trailer"] { for _, key := range strings.Split(v, ",") { key = http.CanonicalHeaderKey(strings.TrimSpace(key)) switch key { @@ -1623,57 +1790,42 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res } } } - delete(header, "Trailer") + delete(rp.header, "Trailer") - body := &requestBody{ - conn: sc, - stream: st, - needsContinue: needsContinue, - } var url_ *url.URL var requestURI string - if isConnect { - url_ = &url.URL{Host: authority} - requestURI = authority // mimic HTTP/1 server behavior + if rp.method == "CONNECT" { + url_ = &url.URL{Host: rp.authority} + requestURI = rp.authority // mimic HTTP/1 server behavior } else { var err error - url_, err = url.ParseRequestURI(path) + url_, err = url.ParseRequestURI(rp.path) if err != nil { - return nil, nil, streamError(f.StreamID, ErrCodeProtocol) + return nil, nil, streamError(st.id, ErrCodeProtocol) } - requestURI = path + requestURI = rp.path + } + + body := &requestBody{ + conn: sc, + stream: st, + needsContinue: needsContinue, } req := &http.Request{ - Method: method, + Method: rp.method, URL: url_, RemoteAddr: sc.remoteAddrStr, - Header: header, + Header: rp.header, RequestURI: requestURI, Proto: "HTTP/2.0", ProtoMajor: 2, ProtoMinor: 0, TLS: tlsState, - Host: authority, + Host: rp.authority, Body: body, Trailer: trailer, } req = requestWithContext(req, st.ctx) - if bodyOpen { - // Disabled, per golang.org/issue/14960: - // st.reqBuf = sc.getRequestBodyBuf() - // TODO: remove this 64k of garbage per request (again, but without a data race): - buf := make([]byte, initialWindowSize) - - body.pipe = &pipe{ - b: &fixedBuffer{buf: buf}, - } - - if vv, ok := header["Content-Length"]; ok { - req.ContentLength, _ = strconv.ParseInt(vv[0], 10, 64) - } else { - req.ContentLength = -1 - } - } rws := responseWriterStatePool.Get().(*responseWriterState) bwSave := rws.bw @@ -1689,13 +1841,22 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res return rw, req, nil } -func (sc *serverConn) getRequestBodyBuf() []byte { - sc.serveG.check() - if buf := sc.freeRequestBodyBuf; buf != nil { - sc.freeRequestBodyBuf = nil - return buf +var reqBodyCache = make(chan []byte, 8) + +func getRequestBodyBuf() []byte { + select { + case b := <-reqBodyCache: + return b + default: + return make([]byte, initialWindowSize) + } +} + +func putRequestBodyBuf(b []byte) { + select { + case reqBodyCache <- b: + default: } - return make([]byte, initialWindowSize) } // Run on its own goroutine. @@ -1705,15 +1866,17 @@ func (sc *serverConn) runHandler(rw *responseWriter, req *http.Request, handler rw.rws.stream.cancelCtx() if didPanic { e := recover() - // Same as net/http: - const size = 64 << 10 - buf := make([]byte, size) - buf = buf[:runtime.Stack(buf, false)] - sc.writeFrameFromHandler(frameWriteMsg{ + sc.writeFrameFromHandler(FrameWriteRequest{ write: handlerPanicRST{rw.rws.stream.id}, stream: rw.rws.stream, }) - sc.logf("http2: panic serving %v: %v\n%s", sc.conn.RemoteAddr(), e, buf) + // Same as net/http: + if shouldLogPanic(e) { + const size = 64 << 10 + buf := make([]byte, size) + buf = buf[:runtime.Stack(buf, false)] + sc.logf("http2: panic serving %v: %v\n%s", sc.conn.RemoteAddr(), e, buf) + } return } rw.handlerDone() @@ -1744,7 +1907,7 @@ func (sc *serverConn) writeHeaders(st *stream, headerData *writeResHeaders) erro // mutates it. errc = errChanPool.Get().(chan error) } - if err := sc.writeFrameFromHandler(frameWriteMsg{ + if err := sc.writeFrameFromHandler(FrameWriteRequest{ write: headerData, stream: st, done: errc, @@ -1767,7 +1930,7 @@ func (sc *serverConn) writeHeaders(st *stream, headerData *writeResHeaders) erro // called from handler goroutines. func (sc *serverConn) write100ContinueHeaders(st *stream) { - sc.writeFrameFromHandler(frameWriteMsg{ + sc.writeFrameFromHandler(FrameWriteRequest{ write: write100ContinueHeadersFrame{st.id}, stream: st, }) @@ -1783,11 +1946,19 @@ type bodyReadMsg struct { // called from handler goroutines. // Notes that the handler for the given stream ID read n bytes of its body // and schedules flow control tokens to be sent. -func (sc *serverConn) noteBodyReadFromHandler(st *stream, n int) { +func (sc *serverConn) noteBodyReadFromHandler(st *stream, n int, err error) { sc.serveG.checkNotOn() // NOT on - select { - case sc.bodyReadCh <- bodyReadMsg{st, n}: - case <-sc.doneServing: + if n > 0 { + select { + case sc.bodyReadCh <- bodyReadMsg{st, n}: + case <-sc.doneServing: + } + } + if err == io.EOF { + if buf := st.reqBuf; buf != nil { + st.reqBuf = nil // shouldn't matter; field unused by other + putRequestBodyBuf(buf) + } } } @@ -1830,7 +2001,7 @@ func (sc *serverConn) sendWindowUpdate32(st *stream, n int32) { if st != nil { streamID = st.id } - sc.writeFrame(frameWriteMsg{ + sc.writeFrame(FrameWriteRequest{ write: writeWindowUpdate{streamID: streamID, n: uint32(n)}, stream: st, }) @@ -1845,16 +2016,19 @@ func (sc *serverConn) sendWindowUpdate32(st *stream, n int32) { } } +// requestBody is the Handler's Request.Body type. +// Read and Close may be called concurrently. type requestBody struct { stream *stream conn *serverConn - closed bool + closed bool // for use by Close only + sawEOF bool // for use by Read only pipe *pipe // non-nil if we have a HTTP entity message body needsContinue bool // need to send a 100-continue } func (b *requestBody) Close() error { - if b.pipe != nil { + if b.pipe != nil && !b.closed { b.pipe.BreakWithError(errClosedBody) } b.closed = true @@ -1866,13 +2040,17 @@ func (b *requestBody) Read(p []byte) (n int, err error) { b.needsContinue = false b.conn.write100ContinueHeaders(b.stream) } - if b.pipe == nil { + if b.pipe == nil || b.sawEOF { return 0, io.EOF } n, err = b.pipe.Read(p) - if n > 0 { - b.conn.noteBodyReadFromHandler(b.stream, n) + if err == io.EOF { + b.sawEOF = true } + if b.conn == nil && inTests { + return + } + b.conn.noteBodyReadFromHandler(b.stream, n, err) return } @@ -2110,8 +2288,9 @@ func (w *responseWriter) CloseNotify() <-chan bool { if ch == nil { ch = make(chan bool, 1) rws.closeNotifierCh = ch + cw := rws.stream.cw go func() { - rws.stream.cw.Wait() // wait for close + cw.Wait() // wait for close ch <- true }() } @@ -2207,6 +2386,200 @@ func (w *responseWriter) handlerDone() { responseWriterStatePool.Put(rws) } +// Push errors. +var ( + ErrRecursivePush = errors.New("http2: recursive push not allowed") + ErrPushLimitReached = errors.New("http2: push would exceed peer's SETTINGS_MAX_CONCURRENT_STREAMS") +) + +// pushOptions is the internal version of http.PushOptions, which we +// cannot include here because it's only defined in Go 1.8 and later. +type pushOptions struct { + Method string + Header http.Header +} + +func (w *responseWriter) push(target string, opts pushOptions) error { + st := w.rws.stream + sc := st.sc + sc.serveG.checkNotOn() + + // No recursive pushes: "PUSH_PROMISE frames MUST only be sent on a peer-initiated stream." + // http://tools.ietf.org/html/rfc7540#section-6.6 + if st.isPushed() { + return ErrRecursivePush + } + + // Default options. + if opts.Method == "" { + opts.Method = "GET" + } + if opts.Header == nil { + opts.Header = http.Header{} + } + wantScheme := "http" + if w.rws.req.TLS != nil { + wantScheme = "https" + } + + // Validate the request. + u, err := url.Parse(target) + if err != nil { + return err + } + if u.Scheme == "" { + if !strings.HasPrefix(target, "/") { + return fmt.Errorf("target must be an absolute URL or an absolute path: %q", target) + } + u.Scheme = wantScheme + u.Host = w.rws.req.Host + } else { + if u.Scheme != wantScheme { + return fmt.Errorf("cannot push URL with scheme %q from request with scheme %q", u.Scheme, wantScheme) + } + if u.Host == "" { + return errors.New("URL must have a host") + } + } + for k := range opts.Header { + if strings.HasPrefix(k, ":") { + return fmt.Errorf("promised request headers cannot include pseudo header %q", k) + } + // These headers are meaningful only if the request has a body, + // but PUSH_PROMISE requests cannot have a body. + // http://tools.ietf.org/html/rfc7540#section-8.2 + // Also disallow Host, since the promised URL must be absolute. + switch strings.ToLower(k) { + case "content-length", "content-encoding", "trailer", "te", "expect", "host": + return fmt.Errorf("promised request headers cannot include %q", k) + } + } + if err := checkValidHTTP2RequestHeaders(opts.Header); err != nil { + return err + } + + // The RFC effectively limits promised requests to GET and HEAD: + // "Promised requests MUST be cacheable [GET, HEAD, or POST], and MUST be safe [GET or HEAD]" + // http://tools.ietf.org/html/rfc7540#section-8.2 + if opts.Method != "GET" && opts.Method != "HEAD" { + return fmt.Errorf("method %q must be GET or HEAD", opts.Method) + } + + msg := startPushRequest{ + parent: st, + method: opts.Method, + url: u, + header: cloneHeader(opts.Header), + done: errChanPool.Get().(chan error), + } + + select { + case <-sc.doneServing: + return errClientDisconnected + case <-st.cw: + return errStreamClosed + case sc.wantStartPushCh <- msg: + } + + select { + case <-sc.doneServing: + return errClientDisconnected + case <-st.cw: + return errStreamClosed + case err := <-msg.done: + errChanPool.Put(msg.done) + return err + } +} + +type startPushRequest struct { + parent *stream + method string + url *url.URL + header http.Header + done chan error +} + +func (sc *serverConn) startPush(msg startPushRequest) { + sc.serveG.check() + + // http://tools.ietf.org/html/rfc7540#section-6.6. + // PUSH_PROMISE frames MUST only be sent on a peer-initiated stream that + // is in either the "open" or "half-closed (remote)" state. + if msg.parent.state != stateOpen && msg.parent.state != stateHalfClosedRemote { + // responseWriter.Push checks that the stream is peer-initiaed. + msg.done <- errStreamClosed + return + } + + // http://tools.ietf.org/html/rfc7540#section-6.6. + if !sc.pushEnabled { + msg.done <- http.ErrNotSupported + return + } + + // PUSH_PROMISE frames must be sent in increasing order by stream ID, so + // we allocate an ID for the promised stream lazily, when the PUSH_PROMISE + // is written. Once the ID is allocated, we start the request handler. + allocatePromisedID := func() (uint32, error) { + sc.serveG.check() + + // Check this again, just in case. Technically, we might have received + // an updated SETTINGS by the time we got around to writing this frame. + if !sc.pushEnabled { + return 0, http.ErrNotSupported + } + // http://tools.ietf.org/html/rfc7540#section-6.5.2. + if sc.curPushedStreams+1 > sc.clientMaxStreams { + return 0, ErrPushLimitReached + } + + // http://tools.ietf.org/html/rfc7540#section-5.1.1. + // Streams initiated by the server MUST use even-numbered identifiers. + // A server that is unable to establish a new stream identifier can send a GOAWAY + // frame so that the client is forced to open a new connection for new streams. + if sc.maxPushPromiseID+2 >= 1<<31 { + sc.startGracefulShutdown() + return 0, ErrPushLimitReached + } + sc.maxPushPromiseID += 2 + promisedID := sc.maxPushPromiseID + + // http://tools.ietf.org/html/rfc7540#section-8.2. + // Strictly speaking, the new stream should start in "reserved (local)", then + // transition to "half closed (remote)" after sending the initial HEADERS, but + // we start in "half closed (remote)" for simplicity. + // See further comments at the definition of stateHalfClosedRemote. + promised := sc.newStream(promisedID, msg.parent.id, stateHalfClosedRemote) + rw, req, err := sc.newWriterAndRequestNoBody(promised, requestParam{ + method: msg.method, + scheme: msg.url.Scheme, + authority: msg.url.Host, + path: msg.url.RequestURI(), + header: msg.header, + }) + if err != nil { + // Should not happen, since we've already validated msg.url. + panic(fmt.Sprintf("newWriterAndRequestNoBody(%+v): %v", msg.url, err)) + } + + go sc.runHandler(rw, req, sc.handler.ServeHTTP) + return promisedID, nil + } + + sc.writeFrame(FrameWriteRequest{ + write: &writePushPromise{ + streamID: msg.parent.id, + method: msg.method, + url: msg.url, + h: msg.header, + allocatePromisedID: allocatePromisedID, + }, + stream: msg.parent, + done: msg.done, + }) +} + // foreachHeaderElement splits v according to the "#rule" construction // in RFC 2616 section 2.1 and calls fn for each non-empty element. func foreachHeaderElement(v string, fn func(string)) { @@ -2234,16 +2607,16 @@ var connHeaders = []string{ "Upgrade", } -// checkValidHTTP2Request checks whether req is a valid HTTP/2 request, +// checkValidHTTP2RequestHeaders checks whether h is a valid HTTP/2 request, // per RFC 7540 Section 8.1.2.2. // The returned error is reported to users. -func checkValidHTTP2Request(req *http.Request) error { - for _, h := range connHeaders { - if _, ok := req.Header[h]; ok { - return fmt.Errorf("request header %q is not valid in HTTP/2", h) +func checkValidHTTP2RequestHeaders(h http.Header) error { + for _, k := range connHeaders { + if _, ok := h[k]; ok { + return fmt.Errorf("request header %q is not valid in HTTP/2", k) } } - te := req.Header["Te"] + te := h["Te"] if len(te) > 0 && (len(te) > 1 || (te[0] != "trailers" && te[0] != "")) { return errors.New(`request header "TE" may only be "trailers" in HTTP/2`) } @@ -2290,3 +2663,42 @@ var badTrailer = map[string]bool{ "Transfer-Encoding": true, "Www-Authenticate": true, } + +// h1ServerShutdownChan returns a channel that will be closed when the +// provided *http.Server wants to shut down. +// +// This is a somewhat hacky way to get at http1 innards. It works +// when the http2 code is bundled into the net/http package in the +// standard library. The alternatives ended up making the cmd/go tool +// depend on http Servers. This is the lightest option for now. +// This is tested via the TestServeShutdown* tests in net/http. +func h1ServerShutdownChan(hs *http.Server) <-chan struct{} { + if fn := testh1ServerShutdownChan; fn != nil { + return fn(hs) + } + var x interface{} = hs + type I interface { + getDoneChan() <-chan struct{} + } + if hs, ok := x.(I); ok { + return hs.getDoneChan() + } + return nil +} + +// optional test hook for h1ServerShutdownChan. +var testh1ServerShutdownChan func(hs *http.Server) <-chan struct{} + +// h1ServerKeepAlivesDisabled reports whether hs has its keep-alives +// disabled. See comments on h1ServerShutdownChan above for why +// the code is written this way. +func h1ServerKeepAlivesDisabled(hs *http.Server) bool { + var x interface{} = hs + type I interface { + doKeepAlives() bool + } + if hs, ok := x.(I); ok { + return !hs.doKeepAlives() + } + return false +} |