William Kurkian | ea86948 | 2019-04-09 15:16:11 -0400 | [diff] [blame] | 1 | // Copyright 2015 The Go Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | // Transport code. |
| 6 | |
| 7 | package http2 |
| 8 | |
| 9 | import ( |
| 10 | "bufio" |
| 11 | "bytes" |
| 12 | "compress/gzip" |
| 13 | "context" |
| 14 | "crypto/rand" |
| 15 | "crypto/tls" |
| 16 | "errors" |
| 17 | "fmt" |
| 18 | "io" |
| 19 | "io/ioutil" |
| 20 | "log" |
| 21 | "math" |
| 22 | mathrand "math/rand" |
| 23 | "net" |
| 24 | "net/http" |
| 25 | "net/http/httptrace" |
| 26 | "net/textproto" |
| 27 | "sort" |
| 28 | "strconv" |
| 29 | "strings" |
| 30 | "sync" |
| 31 | "time" |
| 32 | |
| 33 | "golang.org/x/net/http/httpguts" |
| 34 | "golang.org/x/net/http2/hpack" |
| 35 | "golang.org/x/net/idna" |
| 36 | ) |
| 37 | |
| 38 | const ( |
| 39 | // transportDefaultConnFlow is how many connection-level flow control |
| 40 | // tokens we give the server at start-up, past the default 64k. |
| 41 | transportDefaultConnFlow = 1 << 30 |
| 42 | |
| 43 | // transportDefaultStreamFlow is how many stream-level flow |
| 44 | // control tokens we announce to the peer, and how many bytes |
| 45 | // we buffer per stream. |
| 46 | transportDefaultStreamFlow = 4 << 20 |
| 47 | |
| 48 | // transportDefaultStreamMinRefresh is the minimum number of bytes we'll send |
| 49 | // a stream-level WINDOW_UPDATE for at a time. |
| 50 | transportDefaultStreamMinRefresh = 4 << 10 |
| 51 | |
| 52 | defaultUserAgent = "Go-http-client/2.0" |
| 53 | ) |
| 54 | |
| 55 | // Transport is an HTTP/2 Transport. |
| 56 | // |
| 57 | // A Transport internally caches connections to servers. It is safe |
| 58 | // for concurrent use by multiple goroutines. |
| 59 | type Transport struct { |
| 60 | // DialTLS specifies an optional dial function for creating |
| 61 | // TLS connections for requests. |
| 62 | // |
| 63 | // If DialTLS is nil, tls.Dial is used. |
| 64 | // |
| 65 | // If the returned net.Conn has a ConnectionState method like tls.Conn, |
| 66 | // it will be used to set http.Response.TLS. |
| 67 | DialTLS func(network, addr string, cfg *tls.Config) (net.Conn, error) |
| 68 | |
| 69 | // TLSClientConfig specifies the TLS configuration to use with |
| 70 | // tls.Client. If nil, the default configuration is used. |
| 71 | TLSClientConfig *tls.Config |
| 72 | |
| 73 | // ConnPool optionally specifies an alternate connection pool to use. |
| 74 | // If nil, the default is used. |
| 75 | ConnPool ClientConnPool |
| 76 | |
| 77 | // DisableCompression, if true, prevents the Transport from |
| 78 | // requesting compression with an "Accept-Encoding: gzip" |
| 79 | // request header when the Request contains no existing |
| 80 | // Accept-Encoding value. If the Transport requests gzip on |
| 81 | // its own and gets a gzipped response, it's transparently |
| 82 | // decoded in the Response.Body. However, if the user |
| 83 | // explicitly requested gzip it is not automatically |
| 84 | // uncompressed. |
| 85 | DisableCompression bool |
| 86 | |
| 87 | // AllowHTTP, if true, permits HTTP/2 requests using the insecure, |
| 88 | // plain-text "http" scheme. Note that this does not enable h2c support. |
| 89 | AllowHTTP bool |
| 90 | |
| 91 | // MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to |
| 92 | // send in the initial settings frame. It is how many bytes |
| 93 | // of response headers are allowed. Unlike the http2 spec, zero here |
| 94 | // means to use a default limit (currently 10MB). If you actually |
| 95 | // want to advertise an ulimited value to the peer, Transport |
| 96 | // interprets the highest possible value here (0xffffffff or 1<<32-1) |
| 97 | // to mean no limit. |
| 98 | MaxHeaderListSize uint32 |
| 99 | |
| 100 | // StrictMaxConcurrentStreams controls whether the server's |
| 101 | // SETTINGS_MAX_CONCURRENT_STREAMS should be respected |
| 102 | // globally. If false, new TCP connections are created to the |
| 103 | // server as needed to keep each under the per-connection |
| 104 | // SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the |
| 105 | // server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as |
| 106 | // a global limit and callers of RoundTrip block when needed, |
| 107 | // waiting for their turn. |
| 108 | StrictMaxConcurrentStreams bool |
| 109 | |
| 110 | // t1, if non-nil, is the standard library Transport using |
| 111 | // this transport. Its settings are used (but not its |
| 112 | // RoundTrip method, etc). |
| 113 | t1 *http.Transport |
| 114 | |
| 115 | connPoolOnce sync.Once |
| 116 | connPoolOrDef ClientConnPool // non-nil version of ConnPool |
| 117 | } |
| 118 | |
| 119 | func (t *Transport) maxHeaderListSize() uint32 { |
| 120 | if t.MaxHeaderListSize == 0 { |
| 121 | return 10 << 20 |
| 122 | } |
| 123 | if t.MaxHeaderListSize == 0xffffffff { |
| 124 | return 0 |
| 125 | } |
| 126 | return t.MaxHeaderListSize |
| 127 | } |
| 128 | |
| 129 | func (t *Transport) disableCompression() bool { |
| 130 | return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression) |
| 131 | } |
| 132 | |
| 133 | // ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2. |
| 134 | // It returns an error if t1 has already been HTTP/2-enabled. |
| 135 | func ConfigureTransport(t1 *http.Transport) error { |
| 136 | _, err := configureTransport(t1) |
| 137 | return err |
| 138 | } |
| 139 | |
| 140 | func configureTransport(t1 *http.Transport) (*Transport, error) { |
| 141 | connPool := new(clientConnPool) |
| 142 | t2 := &Transport{ |
| 143 | ConnPool: noDialClientConnPool{connPool}, |
| 144 | t1: t1, |
| 145 | } |
| 146 | connPool.t = t2 |
| 147 | if err := registerHTTPSProtocol(t1, noDialH2RoundTripper{t2}); err != nil { |
| 148 | return nil, err |
| 149 | } |
| 150 | if t1.TLSClientConfig == nil { |
| 151 | t1.TLSClientConfig = new(tls.Config) |
| 152 | } |
| 153 | if !strSliceContains(t1.TLSClientConfig.NextProtos, "h2") { |
| 154 | t1.TLSClientConfig.NextProtos = append([]string{"h2"}, t1.TLSClientConfig.NextProtos...) |
| 155 | } |
| 156 | if !strSliceContains(t1.TLSClientConfig.NextProtos, "http/1.1") { |
| 157 | t1.TLSClientConfig.NextProtos = append(t1.TLSClientConfig.NextProtos, "http/1.1") |
| 158 | } |
| 159 | upgradeFn := func(authority string, c *tls.Conn) http.RoundTripper { |
| 160 | addr := authorityAddr("https", authority) |
| 161 | if used, err := connPool.addConnIfNeeded(addr, t2, c); err != nil { |
| 162 | go c.Close() |
| 163 | return erringRoundTripper{err} |
| 164 | } else if !used { |
| 165 | // Turns out we don't need this c. |
| 166 | // For example, two goroutines made requests to the same host |
| 167 | // at the same time, both kicking off TCP dials. (since protocol |
| 168 | // was unknown) |
| 169 | go c.Close() |
| 170 | } |
| 171 | return t2 |
| 172 | } |
| 173 | if m := t1.TLSNextProto; len(m) == 0 { |
| 174 | t1.TLSNextProto = map[string]func(string, *tls.Conn) http.RoundTripper{ |
| 175 | "h2": upgradeFn, |
| 176 | } |
| 177 | } else { |
| 178 | m["h2"] = upgradeFn |
| 179 | } |
| 180 | return t2, nil |
| 181 | } |
| 182 | |
| 183 | func (t *Transport) connPool() ClientConnPool { |
| 184 | t.connPoolOnce.Do(t.initConnPool) |
| 185 | return t.connPoolOrDef |
| 186 | } |
| 187 | |
| 188 | func (t *Transport) initConnPool() { |
| 189 | if t.ConnPool != nil { |
| 190 | t.connPoolOrDef = t.ConnPool |
| 191 | } else { |
| 192 | t.connPoolOrDef = &clientConnPool{t: t} |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | // ClientConn is the state of a single HTTP/2 client connection to an |
| 197 | // HTTP/2 server. |
| 198 | type ClientConn struct { |
| 199 | t *Transport |
| 200 | tconn net.Conn // usually *tls.Conn, except specialized impls |
| 201 | tlsState *tls.ConnectionState // nil only for specialized impls |
| 202 | singleUse bool // whether being used for a single http.Request |
| 203 | |
| 204 | // readLoop goroutine fields: |
| 205 | readerDone chan struct{} // closed on error |
| 206 | readerErr error // set before readerDone is closed |
| 207 | |
| 208 | idleTimeout time.Duration // or 0 for never |
| 209 | idleTimer *time.Timer |
| 210 | |
| 211 | mu sync.Mutex // guards following |
| 212 | cond *sync.Cond // hold mu; broadcast on flow/closed changes |
| 213 | flow flow // our conn-level flow control quota (cs.flow is per stream) |
| 214 | inflow flow // peer's conn-level flow control |
| 215 | closing bool |
| 216 | closed bool |
| 217 | wantSettingsAck bool // we sent a SETTINGS frame and haven't heard back |
| 218 | goAway *GoAwayFrame // if non-nil, the GoAwayFrame we received |
| 219 | goAwayDebug string // goAway frame's debug data, retained as a string |
| 220 | streams map[uint32]*clientStream // client-initiated |
| 221 | nextStreamID uint32 |
| 222 | pendingRequests int // requests blocked and waiting to be sent because len(streams) == maxConcurrentStreams |
| 223 | pings map[[8]byte]chan struct{} // in flight ping data to notification channel |
| 224 | bw *bufio.Writer |
| 225 | br *bufio.Reader |
| 226 | fr *Framer |
| 227 | lastActive time.Time |
| 228 | // Settings from peer: (also guarded by mu) |
| 229 | maxFrameSize uint32 |
| 230 | maxConcurrentStreams uint32 |
| 231 | peerMaxHeaderListSize uint64 |
| 232 | initialWindowSize uint32 |
| 233 | |
| 234 | hbuf bytes.Buffer // HPACK encoder writes into this |
| 235 | henc *hpack.Encoder |
| 236 | freeBuf [][]byte |
| 237 | |
| 238 | wmu sync.Mutex // held while writing; acquire AFTER mu if holding both |
| 239 | werr error // first write error that has occurred |
| 240 | } |
| 241 | |
| 242 | // clientStream is the state for a single HTTP/2 stream. One of these |
| 243 | // is created for each Transport.RoundTrip call. |
| 244 | type clientStream struct { |
| 245 | cc *ClientConn |
| 246 | req *http.Request |
| 247 | trace *httptrace.ClientTrace // or nil |
| 248 | ID uint32 |
| 249 | resc chan resAndError |
| 250 | bufPipe pipe // buffered pipe with the flow-controlled response payload |
| 251 | startedWrite bool // started request body write; guarded by cc.mu |
| 252 | requestedGzip bool |
| 253 | on100 func() // optional code to run if get a 100 continue response |
| 254 | |
| 255 | flow flow // guarded by cc.mu |
| 256 | inflow flow // guarded by cc.mu |
| 257 | bytesRemain int64 // -1 means unknown; owned by transportResponseBody.Read |
| 258 | readErr error // sticky read error; owned by transportResponseBody.Read |
| 259 | stopReqBody error // if non-nil, stop writing req body; guarded by cc.mu |
| 260 | didReset bool // whether we sent a RST_STREAM to the server; guarded by cc.mu |
| 261 | |
| 262 | peerReset chan struct{} // closed on peer reset |
| 263 | resetErr error // populated before peerReset is closed |
| 264 | |
| 265 | done chan struct{} // closed when stream remove from cc.streams map; close calls guarded by cc.mu |
| 266 | |
| 267 | // owned by clientConnReadLoop: |
| 268 | firstByte bool // got the first response byte |
| 269 | pastHeaders bool // got first MetaHeadersFrame (actual headers) |
| 270 | pastTrailers bool // got optional second MetaHeadersFrame (trailers) |
| 271 | num1xx uint8 // number of 1xx responses seen |
| 272 | |
| 273 | trailer http.Header // accumulated trailers |
| 274 | resTrailer *http.Header // client's Response.Trailer |
| 275 | } |
| 276 | |
| 277 | // awaitRequestCancel waits for the user to cancel a request or for the done |
| 278 | // channel to be signaled. A non-nil error is returned only if the request was |
| 279 | // canceled. |
| 280 | func awaitRequestCancel(req *http.Request, done <-chan struct{}) error { |
| 281 | ctx := req.Context() |
| 282 | if req.Cancel == nil && ctx.Done() == nil { |
| 283 | return nil |
| 284 | } |
| 285 | select { |
| 286 | case <-req.Cancel: |
| 287 | return errRequestCanceled |
| 288 | case <-ctx.Done(): |
| 289 | return ctx.Err() |
| 290 | case <-done: |
| 291 | return nil |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | var got1xxFuncForTests func(int, textproto.MIMEHeader) error |
| 296 | |
| 297 | // get1xxTraceFunc returns the value of request's httptrace.ClientTrace.Got1xxResponse func, |
| 298 | // if any. It returns nil if not set or if the Go version is too old. |
| 299 | func (cs *clientStream) get1xxTraceFunc() func(int, textproto.MIMEHeader) error { |
| 300 | if fn := got1xxFuncForTests; fn != nil { |
| 301 | return fn |
| 302 | } |
| 303 | return traceGot1xxResponseFunc(cs.trace) |
| 304 | } |
| 305 | |
| 306 | // awaitRequestCancel waits for the user to cancel a request, its context to |
| 307 | // expire, or for the request to be done (any way it might be removed from the |
| 308 | // cc.streams map: peer reset, successful completion, TCP connection breakage, |
| 309 | // etc). If the request is canceled, then cs will be canceled and closed. |
| 310 | func (cs *clientStream) awaitRequestCancel(req *http.Request) { |
| 311 | if err := awaitRequestCancel(req, cs.done); err != nil { |
| 312 | cs.cancelStream() |
| 313 | cs.bufPipe.CloseWithError(err) |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | func (cs *clientStream) cancelStream() { |
| 318 | cc := cs.cc |
| 319 | cc.mu.Lock() |
| 320 | didReset := cs.didReset |
| 321 | cs.didReset = true |
| 322 | cc.mu.Unlock() |
| 323 | |
| 324 | if !didReset { |
| 325 | cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) |
| 326 | cc.forgetStreamID(cs.ID) |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | // checkResetOrDone reports any error sent in a RST_STREAM frame by the |
| 331 | // server, or errStreamClosed if the stream is complete. |
| 332 | func (cs *clientStream) checkResetOrDone() error { |
| 333 | select { |
| 334 | case <-cs.peerReset: |
| 335 | return cs.resetErr |
| 336 | case <-cs.done: |
| 337 | return errStreamClosed |
| 338 | default: |
| 339 | return nil |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | func (cs *clientStream) getStartedWrite() bool { |
| 344 | cc := cs.cc |
| 345 | cc.mu.Lock() |
| 346 | defer cc.mu.Unlock() |
| 347 | return cs.startedWrite |
| 348 | } |
| 349 | |
| 350 | func (cs *clientStream) abortRequestBodyWrite(err error) { |
| 351 | if err == nil { |
| 352 | panic("nil error") |
| 353 | } |
| 354 | cc := cs.cc |
| 355 | cc.mu.Lock() |
| 356 | cs.stopReqBody = err |
| 357 | cc.cond.Broadcast() |
| 358 | cc.mu.Unlock() |
| 359 | } |
| 360 | |
| 361 | type stickyErrWriter struct { |
| 362 | w io.Writer |
| 363 | err *error |
| 364 | } |
| 365 | |
| 366 | func (sew stickyErrWriter) Write(p []byte) (n int, err error) { |
| 367 | if *sew.err != nil { |
| 368 | return 0, *sew.err |
| 369 | } |
| 370 | n, err = sew.w.Write(p) |
| 371 | *sew.err = err |
| 372 | return |
| 373 | } |
| 374 | |
| 375 | // noCachedConnError is the concrete type of ErrNoCachedConn, which |
| 376 | // needs to be detected by net/http regardless of whether it's its |
| 377 | // bundled version (in h2_bundle.go with a rewritten type name) or |
| 378 | // from a user's x/net/http2. As such, as it has a unique method name |
| 379 | // (IsHTTP2NoCachedConnError) that net/http sniffs for via func |
| 380 | // isNoCachedConnError. |
| 381 | type noCachedConnError struct{} |
| 382 | |
| 383 | func (noCachedConnError) IsHTTP2NoCachedConnError() {} |
| 384 | func (noCachedConnError) Error() string { return "http2: no cached connection was available" } |
| 385 | |
| 386 | // isNoCachedConnError reports whether err is of type noCachedConnError |
| 387 | // or its equivalent renamed type in net/http2's h2_bundle.go. Both types |
| 388 | // may coexist in the same running program. |
| 389 | func isNoCachedConnError(err error) bool { |
| 390 | _, ok := err.(interface{ IsHTTP2NoCachedConnError() }) |
| 391 | return ok |
| 392 | } |
| 393 | |
| 394 | var ErrNoCachedConn error = noCachedConnError{} |
| 395 | |
| 396 | // RoundTripOpt are options for the Transport.RoundTripOpt method. |
| 397 | type RoundTripOpt struct { |
| 398 | // OnlyCachedConn controls whether RoundTripOpt may |
| 399 | // create a new TCP connection. If set true and |
| 400 | // no cached connection is available, RoundTripOpt |
| 401 | // will return ErrNoCachedConn. |
| 402 | OnlyCachedConn bool |
| 403 | } |
| 404 | |
| 405 | func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) { |
| 406 | return t.RoundTripOpt(req, RoundTripOpt{}) |
| 407 | } |
| 408 | |
| 409 | // authorityAddr returns a given authority (a host/IP, or host:port / ip:port) |
| 410 | // and returns a host:port. The port 443 is added if needed. |
| 411 | func authorityAddr(scheme string, authority string) (addr string) { |
| 412 | host, port, err := net.SplitHostPort(authority) |
| 413 | if err != nil { // authority didn't have a port |
| 414 | port = "443" |
| 415 | if scheme == "http" { |
| 416 | port = "80" |
| 417 | } |
| 418 | host = authority |
| 419 | } |
| 420 | if a, err := idna.ToASCII(host); err == nil { |
| 421 | host = a |
| 422 | } |
| 423 | // IPv6 address literal, without a port: |
| 424 | if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") { |
| 425 | return host + ":" + port |
| 426 | } |
| 427 | return net.JoinHostPort(host, port) |
| 428 | } |
| 429 | |
| 430 | // RoundTripOpt is like RoundTrip, but takes options. |
| 431 | func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) { |
| 432 | if !(req.URL.Scheme == "https" || (req.URL.Scheme == "http" && t.AllowHTTP)) { |
| 433 | return nil, errors.New("http2: unsupported scheme") |
| 434 | } |
| 435 | |
| 436 | addr := authorityAddr(req.URL.Scheme, req.URL.Host) |
| 437 | for retry := 0; ; retry++ { |
| 438 | cc, err := t.connPool().GetClientConn(req, addr) |
| 439 | if err != nil { |
| 440 | t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err) |
| 441 | return nil, err |
| 442 | } |
| 443 | traceGotConn(req, cc) |
| 444 | res, gotErrAfterReqBodyWrite, err := cc.roundTrip(req) |
| 445 | if err != nil && retry <= 6 { |
| 446 | if req, err = shouldRetryRequest(req, err, gotErrAfterReqBodyWrite); err == nil { |
| 447 | // After the first retry, do exponential backoff with 10% jitter. |
| 448 | if retry == 0 { |
| 449 | continue |
| 450 | } |
| 451 | backoff := float64(uint(1) << (uint(retry) - 1)) |
| 452 | backoff += backoff * (0.1 * mathrand.Float64()) |
| 453 | select { |
| 454 | case <-time.After(time.Second * time.Duration(backoff)): |
| 455 | continue |
| 456 | case <-req.Context().Done(): |
| 457 | return nil, req.Context().Err() |
| 458 | } |
| 459 | } |
| 460 | } |
| 461 | if err != nil { |
| 462 | t.vlogf("RoundTrip failure: %v", err) |
| 463 | return nil, err |
| 464 | } |
| 465 | return res, nil |
| 466 | } |
| 467 | } |
| 468 | |
| 469 | // CloseIdleConnections closes any connections which were previously |
| 470 | // connected from previous requests but are now sitting idle. |
| 471 | // It does not interrupt any connections currently in use. |
| 472 | func (t *Transport) CloseIdleConnections() { |
| 473 | if cp, ok := t.connPool().(clientConnPoolIdleCloser); ok { |
| 474 | cp.closeIdleConnections() |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | var ( |
| 479 | errClientConnClosed = errors.New("http2: client conn is closed") |
| 480 | errClientConnUnusable = errors.New("http2: client conn not usable") |
| 481 | errClientConnGotGoAway = errors.New("http2: Transport received Server's graceful shutdown GOAWAY") |
| 482 | ) |
| 483 | |
| 484 | // shouldRetryRequest is called by RoundTrip when a request fails to get |
| 485 | // response headers. It is always called with a non-nil error. |
| 486 | // It returns either a request to retry (either the same request, or a |
| 487 | // modified clone), or an error if the request can't be replayed. |
| 488 | func shouldRetryRequest(req *http.Request, err error, afterBodyWrite bool) (*http.Request, error) { |
| 489 | if !canRetryError(err) { |
| 490 | return nil, err |
| 491 | } |
| 492 | // If the Body is nil (or http.NoBody), it's safe to reuse |
| 493 | // this request and its Body. |
| 494 | if req.Body == nil || req.Body == http.NoBody { |
| 495 | return req, nil |
| 496 | } |
| 497 | |
| 498 | // If the request body can be reset back to its original |
| 499 | // state via the optional req.GetBody, do that. |
| 500 | if req.GetBody != nil { |
| 501 | // TODO: consider a req.Body.Close here? or audit that all caller paths do? |
| 502 | body, err := req.GetBody() |
| 503 | if err != nil { |
| 504 | return nil, err |
| 505 | } |
| 506 | newReq := *req |
| 507 | newReq.Body = body |
| 508 | return &newReq, nil |
| 509 | } |
| 510 | |
| 511 | // The Request.Body can't reset back to the beginning, but we |
| 512 | // don't seem to have started to read from it yet, so reuse |
| 513 | // the request directly. The "afterBodyWrite" means the |
| 514 | // bodyWrite process has started, which becomes true before |
| 515 | // the first Read. |
| 516 | if !afterBodyWrite { |
| 517 | return req, nil |
| 518 | } |
| 519 | |
| 520 | return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err) |
| 521 | } |
| 522 | |
| 523 | func canRetryError(err error) bool { |
| 524 | if err == errClientConnUnusable || err == errClientConnGotGoAway { |
| 525 | return true |
| 526 | } |
| 527 | if se, ok := err.(StreamError); ok { |
| 528 | return se.Code == ErrCodeRefusedStream |
| 529 | } |
| 530 | return false |
| 531 | } |
| 532 | |
| 533 | func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, error) { |
| 534 | host, _, err := net.SplitHostPort(addr) |
| 535 | if err != nil { |
| 536 | return nil, err |
| 537 | } |
| 538 | tconn, err := t.dialTLS()("tcp", addr, t.newTLSConfig(host)) |
| 539 | if err != nil { |
| 540 | return nil, err |
| 541 | } |
| 542 | return t.newClientConn(tconn, singleUse) |
| 543 | } |
| 544 | |
| 545 | func (t *Transport) newTLSConfig(host string) *tls.Config { |
| 546 | cfg := new(tls.Config) |
| 547 | if t.TLSClientConfig != nil { |
| 548 | *cfg = *t.TLSClientConfig.Clone() |
| 549 | } |
| 550 | if !strSliceContains(cfg.NextProtos, NextProtoTLS) { |
| 551 | cfg.NextProtos = append([]string{NextProtoTLS}, cfg.NextProtos...) |
| 552 | } |
| 553 | if cfg.ServerName == "" { |
| 554 | cfg.ServerName = host |
| 555 | } |
| 556 | return cfg |
| 557 | } |
| 558 | |
| 559 | func (t *Transport) dialTLS() func(string, string, *tls.Config) (net.Conn, error) { |
| 560 | if t.DialTLS != nil { |
| 561 | return t.DialTLS |
| 562 | } |
| 563 | return t.dialTLSDefault |
| 564 | } |
| 565 | |
| 566 | func (t *Transport) dialTLSDefault(network, addr string, cfg *tls.Config) (net.Conn, error) { |
| 567 | cn, err := tls.Dial(network, addr, cfg) |
| 568 | if err != nil { |
| 569 | return nil, err |
| 570 | } |
| 571 | if err := cn.Handshake(); err != nil { |
| 572 | return nil, err |
| 573 | } |
| 574 | if !cfg.InsecureSkipVerify { |
| 575 | if err := cn.VerifyHostname(cfg.ServerName); err != nil { |
| 576 | return nil, err |
| 577 | } |
| 578 | } |
| 579 | state := cn.ConnectionState() |
| 580 | if p := state.NegotiatedProtocol; p != NextProtoTLS { |
| 581 | return nil, fmt.Errorf("http2: unexpected ALPN protocol %q; want %q", p, NextProtoTLS) |
| 582 | } |
| 583 | if !state.NegotiatedProtocolIsMutual { |
| 584 | return nil, errors.New("http2: could not negotiate protocol mutually") |
| 585 | } |
| 586 | return cn, nil |
| 587 | } |
| 588 | |
| 589 | // disableKeepAlives reports whether connections should be closed as |
| 590 | // soon as possible after handling the first request. |
| 591 | func (t *Transport) disableKeepAlives() bool { |
| 592 | return t.t1 != nil && t.t1.DisableKeepAlives |
| 593 | } |
| 594 | |
| 595 | func (t *Transport) expectContinueTimeout() time.Duration { |
| 596 | if t.t1 == nil { |
| 597 | return 0 |
| 598 | } |
| 599 | return t.t1.ExpectContinueTimeout |
| 600 | } |
| 601 | |
| 602 | func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) { |
| 603 | return t.newClientConn(c, false) |
| 604 | } |
| 605 | |
| 606 | func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, error) { |
| 607 | cc := &ClientConn{ |
| 608 | t: t, |
| 609 | tconn: c, |
| 610 | readerDone: make(chan struct{}), |
| 611 | nextStreamID: 1, |
| 612 | maxFrameSize: 16 << 10, // spec default |
| 613 | initialWindowSize: 65535, // spec default |
| 614 | maxConcurrentStreams: 1000, // "infinite", per spec. 1000 seems good enough. |
| 615 | peerMaxHeaderListSize: 0xffffffffffffffff, // "infinite", per spec. Use 2^64-1 instead. |
| 616 | streams: make(map[uint32]*clientStream), |
| 617 | singleUse: singleUse, |
| 618 | wantSettingsAck: true, |
| 619 | pings: make(map[[8]byte]chan struct{}), |
| 620 | } |
| 621 | if d := t.idleConnTimeout(); d != 0 { |
| 622 | cc.idleTimeout = d |
| 623 | cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout) |
| 624 | } |
| 625 | if VerboseLogs { |
| 626 | t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr()) |
| 627 | } |
| 628 | |
| 629 | cc.cond = sync.NewCond(&cc.mu) |
| 630 | cc.flow.add(int32(initialWindowSize)) |
| 631 | |
| 632 | // TODO: adjust this writer size to account for frame size + |
| 633 | // MTU + crypto/tls record padding. |
| 634 | cc.bw = bufio.NewWriter(stickyErrWriter{c, &cc.werr}) |
| 635 | cc.br = bufio.NewReader(c) |
| 636 | cc.fr = NewFramer(cc.bw, cc.br) |
| 637 | cc.fr.ReadMetaHeaders = hpack.NewDecoder(initialHeaderTableSize, nil) |
| 638 | cc.fr.MaxHeaderListSize = t.maxHeaderListSize() |
| 639 | |
| 640 | // TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on |
| 641 | // henc in response to SETTINGS frames? |
| 642 | cc.henc = hpack.NewEncoder(&cc.hbuf) |
| 643 | |
| 644 | if t.AllowHTTP { |
| 645 | cc.nextStreamID = 3 |
| 646 | } |
| 647 | |
| 648 | if cs, ok := c.(connectionStater); ok { |
| 649 | state := cs.ConnectionState() |
| 650 | cc.tlsState = &state |
| 651 | } |
| 652 | |
| 653 | initialSettings := []Setting{ |
| 654 | {ID: SettingEnablePush, Val: 0}, |
| 655 | {ID: SettingInitialWindowSize, Val: transportDefaultStreamFlow}, |
| 656 | } |
| 657 | if max := t.maxHeaderListSize(); max != 0 { |
| 658 | initialSettings = append(initialSettings, Setting{ID: SettingMaxHeaderListSize, Val: max}) |
| 659 | } |
| 660 | |
| 661 | cc.bw.Write(clientPreface) |
| 662 | cc.fr.WriteSettings(initialSettings...) |
| 663 | cc.fr.WriteWindowUpdate(0, transportDefaultConnFlow) |
| 664 | cc.inflow.add(transportDefaultConnFlow + initialWindowSize) |
| 665 | cc.bw.Flush() |
| 666 | if cc.werr != nil { |
| 667 | return nil, cc.werr |
| 668 | } |
| 669 | |
| 670 | go cc.readLoop() |
| 671 | return cc, nil |
| 672 | } |
| 673 | |
| 674 | func (cc *ClientConn) setGoAway(f *GoAwayFrame) { |
| 675 | cc.mu.Lock() |
| 676 | defer cc.mu.Unlock() |
| 677 | |
| 678 | old := cc.goAway |
| 679 | cc.goAway = f |
| 680 | |
| 681 | // Merge the previous and current GoAway error frames. |
| 682 | if cc.goAwayDebug == "" { |
| 683 | cc.goAwayDebug = string(f.DebugData()) |
| 684 | } |
| 685 | if old != nil && old.ErrCode != ErrCodeNo { |
| 686 | cc.goAway.ErrCode = old.ErrCode |
| 687 | } |
| 688 | last := f.LastStreamID |
| 689 | for streamID, cs := range cc.streams { |
| 690 | if streamID > last { |
| 691 | select { |
| 692 | case cs.resc <- resAndError{err: errClientConnGotGoAway}: |
| 693 | default: |
| 694 | } |
| 695 | } |
| 696 | } |
| 697 | } |
| 698 | |
| 699 | // CanTakeNewRequest reports whether the connection can take a new request, |
| 700 | // meaning it has not been closed or received or sent a GOAWAY. |
| 701 | func (cc *ClientConn) CanTakeNewRequest() bool { |
| 702 | cc.mu.Lock() |
| 703 | defer cc.mu.Unlock() |
| 704 | return cc.canTakeNewRequestLocked() |
| 705 | } |
| 706 | |
| 707 | // clientConnIdleState describes the suitability of a client |
| 708 | // connection to initiate a new RoundTrip request. |
| 709 | type clientConnIdleState struct { |
| 710 | canTakeNewRequest bool |
| 711 | freshConn bool // whether it's unused by any previous request |
| 712 | } |
| 713 | |
| 714 | func (cc *ClientConn) idleState() clientConnIdleState { |
| 715 | cc.mu.Lock() |
| 716 | defer cc.mu.Unlock() |
| 717 | return cc.idleStateLocked() |
| 718 | } |
| 719 | |
| 720 | func (cc *ClientConn) idleStateLocked() (st clientConnIdleState) { |
| 721 | if cc.singleUse && cc.nextStreamID > 1 { |
| 722 | return |
| 723 | } |
| 724 | var maxConcurrentOkay bool |
| 725 | if cc.t.StrictMaxConcurrentStreams { |
| 726 | // We'll tell the caller we can take a new request to |
| 727 | // prevent the caller from dialing a new TCP |
| 728 | // connection, but then we'll block later before |
| 729 | // writing it. |
| 730 | maxConcurrentOkay = true |
| 731 | } else { |
| 732 | maxConcurrentOkay = int64(len(cc.streams)+1) < int64(cc.maxConcurrentStreams) |
| 733 | } |
| 734 | |
| 735 | st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && maxConcurrentOkay && |
| 736 | int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32 |
| 737 | st.freshConn = cc.nextStreamID == 1 && st.canTakeNewRequest |
| 738 | return |
| 739 | } |
| 740 | |
| 741 | func (cc *ClientConn) canTakeNewRequestLocked() bool { |
| 742 | st := cc.idleStateLocked() |
| 743 | return st.canTakeNewRequest |
| 744 | } |
| 745 | |
| 746 | // onIdleTimeout is called from a time.AfterFunc goroutine. It will |
| 747 | // only be called when we're idle, but because we're coming from a new |
| 748 | // goroutine, there could be a new request coming in at the same time, |
| 749 | // so this simply calls the synchronized closeIfIdle to shut down this |
| 750 | // connection. The timer could just call closeIfIdle, but this is more |
| 751 | // clear. |
| 752 | func (cc *ClientConn) onIdleTimeout() { |
| 753 | cc.closeIfIdle() |
| 754 | } |
| 755 | |
| 756 | func (cc *ClientConn) closeIfIdle() { |
| 757 | cc.mu.Lock() |
| 758 | if len(cc.streams) > 0 { |
| 759 | cc.mu.Unlock() |
| 760 | return |
| 761 | } |
| 762 | cc.closed = true |
| 763 | nextID := cc.nextStreamID |
| 764 | // TODO: do clients send GOAWAY too? maybe? Just Close: |
| 765 | cc.mu.Unlock() |
| 766 | |
| 767 | if VerboseLogs { |
| 768 | cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2) |
| 769 | } |
| 770 | cc.tconn.Close() |
| 771 | } |
| 772 | |
| 773 | var shutdownEnterWaitStateHook = func() {} |
| 774 | |
| 775 | // Shutdown gracefully close the client connection, waiting for running streams to complete. |
| 776 | func (cc *ClientConn) Shutdown(ctx context.Context) error { |
| 777 | if err := cc.sendGoAway(); err != nil { |
| 778 | return err |
| 779 | } |
| 780 | // Wait for all in-flight streams to complete or connection to close |
| 781 | done := make(chan error, 1) |
| 782 | cancelled := false // guarded by cc.mu |
| 783 | go func() { |
| 784 | cc.mu.Lock() |
| 785 | defer cc.mu.Unlock() |
| 786 | for { |
| 787 | if len(cc.streams) == 0 || cc.closed { |
| 788 | cc.closed = true |
| 789 | done <- cc.tconn.Close() |
| 790 | break |
| 791 | } |
| 792 | if cancelled { |
| 793 | break |
| 794 | } |
| 795 | cc.cond.Wait() |
| 796 | } |
| 797 | }() |
| 798 | shutdownEnterWaitStateHook() |
| 799 | select { |
| 800 | case err := <-done: |
| 801 | return err |
| 802 | case <-ctx.Done(): |
| 803 | cc.mu.Lock() |
| 804 | // Free the goroutine above |
| 805 | cancelled = true |
| 806 | cc.cond.Broadcast() |
| 807 | cc.mu.Unlock() |
| 808 | return ctx.Err() |
| 809 | } |
| 810 | } |
| 811 | |
| 812 | func (cc *ClientConn) sendGoAway() error { |
| 813 | cc.mu.Lock() |
| 814 | defer cc.mu.Unlock() |
| 815 | cc.wmu.Lock() |
| 816 | defer cc.wmu.Unlock() |
| 817 | if cc.closing { |
| 818 | // GOAWAY sent already |
| 819 | return nil |
| 820 | } |
| 821 | // Send a graceful shutdown frame to server |
| 822 | maxStreamID := cc.nextStreamID |
| 823 | if err := cc.fr.WriteGoAway(maxStreamID, ErrCodeNo, nil); err != nil { |
| 824 | return err |
| 825 | } |
| 826 | if err := cc.bw.Flush(); err != nil { |
| 827 | return err |
| 828 | } |
| 829 | // Prevent new requests |
| 830 | cc.closing = true |
| 831 | return nil |
| 832 | } |
| 833 | |
| 834 | // Close closes the client connection immediately. |
| 835 | // |
| 836 | // In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead. |
| 837 | func (cc *ClientConn) Close() error { |
| 838 | cc.mu.Lock() |
| 839 | defer cc.cond.Broadcast() |
| 840 | defer cc.mu.Unlock() |
| 841 | err := errors.New("http2: client connection force closed via ClientConn.Close") |
| 842 | for id, cs := range cc.streams { |
| 843 | select { |
| 844 | case cs.resc <- resAndError{err: err}: |
| 845 | default: |
| 846 | } |
| 847 | cs.bufPipe.CloseWithError(err) |
| 848 | delete(cc.streams, id) |
| 849 | } |
| 850 | cc.closed = true |
| 851 | return cc.tconn.Close() |
| 852 | } |
| 853 | |
| 854 | const maxAllocFrameSize = 512 << 10 |
| 855 | |
| 856 | // frameBuffer returns a scratch buffer suitable for writing DATA frames. |
| 857 | // They're capped at the min of the peer's max frame size or 512KB |
| 858 | // (kinda arbitrarily), but definitely capped so we don't allocate 4GB |
| 859 | // bufers. |
| 860 | func (cc *ClientConn) frameScratchBuffer() []byte { |
| 861 | cc.mu.Lock() |
| 862 | size := cc.maxFrameSize |
| 863 | if size > maxAllocFrameSize { |
| 864 | size = maxAllocFrameSize |
| 865 | } |
| 866 | for i, buf := range cc.freeBuf { |
| 867 | if len(buf) >= int(size) { |
| 868 | cc.freeBuf[i] = nil |
| 869 | cc.mu.Unlock() |
| 870 | return buf[:size] |
| 871 | } |
| 872 | } |
| 873 | cc.mu.Unlock() |
| 874 | return make([]byte, size) |
| 875 | } |
| 876 | |
| 877 | func (cc *ClientConn) putFrameScratchBuffer(buf []byte) { |
| 878 | cc.mu.Lock() |
| 879 | defer cc.mu.Unlock() |
| 880 | const maxBufs = 4 // arbitrary; 4 concurrent requests per conn? investigate. |
| 881 | if len(cc.freeBuf) < maxBufs { |
| 882 | cc.freeBuf = append(cc.freeBuf, buf) |
| 883 | return |
| 884 | } |
| 885 | for i, old := range cc.freeBuf { |
| 886 | if old == nil { |
| 887 | cc.freeBuf[i] = buf |
| 888 | return |
| 889 | } |
| 890 | } |
| 891 | // forget about it. |
| 892 | } |
| 893 | |
| 894 | // errRequestCanceled is a copy of net/http's errRequestCanceled because it's not |
| 895 | // exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests. |
| 896 | var errRequestCanceled = errors.New("net/http: request canceled") |
| 897 | |
| 898 | func commaSeparatedTrailers(req *http.Request) (string, error) { |
| 899 | keys := make([]string, 0, len(req.Trailer)) |
| 900 | for k := range req.Trailer { |
| 901 | k = http.CanonicalHeaderKey(k) |
| 902 | switch k { |
| 903 | case "Transfer-Encoding", "Trailer", "Content-Length": |
| 904 | return "", &badStringError{"invalid Trailer key", k} |
| 905 | } |
| 906 | keys = append(keys, k) |
| 907 | } |
| 908 | if len(keys) > 0 { |
| 909 | sort.Strings(keys) |
| 910 | return strings.Join(keys, ","), nil |
| 911 | } |
| 912 | return "", nil |
| 913 | } |
| 914 | |
| 915 | func (cc *ClientConn) responseHeaderTimeout() time.Duration { |
| 916 | if cc.t.t1 != nil { |
| 917 | return cc.t.t1.ResponseHeaderTimeout |
| 918 | } |
| 919 | // No way to do this (yet?) with just an http2.Transport. Probably |
| 920 | // no need. Request.Cancel this is the new way. We only need to support |
| 921 | // this for compatibility with the old http.Transport fields when |
| 922 | // we're doing transparent http2. |
| 923 | return 0 |
| 924 | } |
| 925 | |
| 926 | // checkConnHeaders checks whether req has any invalid connection-level headers. |
| 927 | // per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields. |
| 928 | // Certain headers are special-cased as okay but not transmitted later. |
| 929 | func checkConnHeaders(req *http.Request) error { |
| 930 | if v := req.Header.Get("Upgrade"); v != "" { |
| 931 | return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"]) |
| 932 | } |
| 933 | if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") { |
| 934 | return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv) |
| 935 | } |
| 936 | if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !strings.EqualFold(vv[0], "close") && !strings.EqualFold(vv[0], "keep-alive")) { |
| 937 | return fmt.Errorf("http2: invalid Connection request header: %q", vv) |
| 938 | } |
| 939 | return nil |
| 940 | } |
| 941 | |
| 942 | // actualContentLength returns a sanitized version of |
| 943 | // req.ContentLength, where 0 actually means zero (not unknown) and -1 |
| 944 | // means unknown. |
| 945 | func actualContentLength(req *http.Request) int64 { |
| 946 | if req.Body == nil || req.Body == http.NoBody { |
| 947 | return 0 |
| 948 | } |
| 949 | if req.ContentLength != 0 { |
| 950 | return req.ContentLength |
| 951 | } |
| 952 | return -1 |
| 953 | } |
| 954 | |
| 955 | func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) { |
| 956 | resp, _, err := cc.roundTrip(req) |
| 957 | return resp, err |
| 958 | } |
| 959 | |
| 960 | func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAfterReqBodyWrite bool, err error) { |
| 961 | if err := checkConnHeaders(req); err != nil { |
| 962 | return nil, false, err |
| 963 | } |
| 964 | if cc.idleTimer != nil { |
| 965 | cc.idleTimer.Stop() |
| 966 | } |
| 967 | |
| 968 | trailers, err := commaSeparatedTrailers(req) |
| 969 | if err != nil { |
| 970 | return nil, false, err |
| 971 | } |
| 972 | hasTrailers := trailers != "" |
| 973 | |
| 974 | cc.mu.Lock() |
| 975 | if err := cc.awaitOpenSlotForRequest(req); err != nil { |
| 976 | cc.mu.Unlock() |
| 977 | return nil, false, err |
| 978 | } |
| 979 | |
| 980 | body := req.Body |
| 981 | contentLen := actualContentLength(req) |
| 982 | hasBody := contentLen != 0 |
| 983 | |
| 984 | // TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere? |
| 985 | var requestedGzip bool |
| 986 | if !cc.t.disableCompression() && |
| 987 | req.Header.Get("Accept-Encoding") == "" && |
| 988 | req.Header.Get("Range") == "" && |
| 989 | req.Method != "HEAD" { |
| 990 | // Request gzip only, not deflate. Deflate is ambiguous and |
| 991 | // not as universally supported anyway. |
| 992 | // See: http://www.gzip.org/zlib/zlib_faq.html#faq38 |
| 993 | // |
| 994 | // Note that we don't request this for HEAD requests, |
| 995 | // due to a bug in nginx: |
| 996 | // http://trac.nginx.org/nginx/ticket/358 |
| 997 | // https://golang.org/issue/5522 |
| 998 | // |
| 999 | // We don't request gzip if the request is for a range, since |
| 1000 | // auto-decoding a portion of a gzipped document will just fail |
| 1001 | // anyway. See https://golang.org/issue/8923 |
| 1002 | requestedGzip = true |
| 1003 | } |
| 1004 | |
| 1005 | // we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is |
| 1006 | // sent by writeRequestBody below, along with any Trailers, |
| 1007 | // again in form HEADERS{1}, CONTINUATION{0,}) |
| 1008 | hdrs, err := cc.encodeHeaders(req, requestedGzip, trailers, contentLen) |
| 1009 | if err != nil { |
| 1010 | cc.mu.Unlock() |
| 1011 | return nil, false, err |
| 1012 | } |
| 1013 | |
| 1014 | cs := cc.newStream() |
| 1015 | cs.req = req |
| 1016 | cs.trace = httptrace.ContextClientTrace(req.Context()) |
| 1017 | cs.requestedGzip = requestedGzip |
| 1018 | bodyWriter := cc.t.getBodyWriterState(cs, body) |
| 1019 | cs.on100 = bodyWriter.on100 |
| 1020 | |
| 1021 | cc.wmu.Lock() |
| 1022 | endStream := !hasBody && !hasTrailers |
| 1023 | werr := cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs) |
| 1024 | cc.wmu.Unlock() |
| 1025 | traceWroteHeaders(cs.trace) |
| 1026 | cc.mu.Unlock() |
| 1027 | |
| 1028 | if werr != nil { |
| 1029 | if hasBody { |
| 1030 | req.Body.Close() // per RoundTripper contract |
| 1031 | bodyWriter.cancel() |
| 1032 | } |
| 1033 | cc.forgetStreamID(cs.ID) |
| 1034 | // Don't bother sending a RST_STREAM (our write already failed; |
| 1035 | // no need to keep writing) |
| 1036 | traceWroteRequest(cs.trace, werr) |
| 1037 | return nil, false, werr |
| 1038 | } |
| 1039 | |
| 1040 | var respHeaderTimer <-chan time.Time |
| 1041 | if hasBody { |
| 1042 | bodyWriter.scheduleBodyWrite() |
| 1043 | } else { |
| 1044 | traceWroteRequest(cs.trace, nil) |
| 1045 | if d := cc.responseHeaderTimeout(); d != 0 { |
| 1046 | timer := time.NewTimer(d) |
| 1047 | defer timer.Stop() |
| 1048 | respHeaderTimer = timer.C |
| 1049 | } |
| 1050 | } |
| 1051 | |
| 1052 | readLoopResCh := cs.resc |
| 1053 | bodyWritten := false |
| 1054 | ctx := req.Context() |
| 1055 | |
| 1056 | handleReadLoopResponse := func(re resAndError) (*http.Response, bool, error) { |
| 1057 | res := re.res |
| 1058 | if re.err != nil || res.StatusCode > 299 { |
| 1059 | // On error or status code 3xx, 4xx, 5xx, etc abort any |
| 1060 | // ongoing write, assuming that the server doesn't care |
| 1061 | // about our request body. If the server replied with 1xx or |
| 1062 | // 2xx, however, then assume the server DOES potentially |
| 1063 | // want our body (e.g. full-duplex streaming: |
| 1064 | // golang.org/issue/13444). If it turns out the server |
| 1065 | // doesn't, they'll RST_STREAM us soon enough. This is a |
| 1066 | // heuristic to avoid adding knobs to Transport. Hopefully |
| 1067 | // we can keep it. |
| 1068 | bodyWriter.cancel() |
| 1069 | cs.abortRequestBodyWrite(errStopReqBodyWrite) |
| 1070 | } |
| 1071 | if re.err != nil { |
| 1072 | cc.forgetStreamID(cs.ID) |
| 1073 | return nil, cs.getStartedWrite(), re.err |
| 1074 | } |
| 1075 | res.Request = req |
| 1076 | res.TLS = cc.tlsState |
| 1077 | return res, false, nil |
| 1078 | } |
| 1079 | |
| 1080 | for { |
| 1081 | select { |
| 1082 | case re := <-readLoopResCh: |
| 1083 | return handleReadLoopResponse(re) |
| 1084 | case <-respHeaderTimer: |
| 1085 | if !hasBody || bodyWritten { |
| 1086 | cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) |
| 1087 | } else { |
| 1088 | bodyWriter.cancel() |
| 1089 | cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) |
| 1090 | } |
| 1091 | cc.forgetStreamID(cs.ID) |
| 1092 | return nil, cs.getStartedWrite(), errTimeout |
| 1093 | case <-ctx.Done(): |
| 1094 | if !hasBody || bodyWritten { |
| 1095 | cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) |
| 1096 | } else { |
| 1097 | bodyWriter.cancel() |
| 1098 | cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) |
| 1099 | } |
| 1100 | cc.forgetStreamID(cs.ID) |
| 1101 | return nil, cs.getStartedWrite(), ctx.Err() |
| 1102 | case <-req.Cancel: |
| 1103 | if !hasBody || bodyWritten { |
| 1104 | cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) |
| 1105 | } else { |
| 1106 | bodyWriter.cancel() |
| 1107 | cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) |
| 1108 | } |
| 1109 | cc.forgetStreamID(cs.ID) |
| 1110 | return nil, cs.getStartedWrite(), errRequestCanceled |
| 1111 | case <-cs.peerReset: |
| 1112 | // processResetStream already removed the |
| 1113 | // stream from the streams map; no need for |
| 1114 | // forgetStreamID. |
| 1115 | return nil, cs.getStartedWrite(), cs.resetErr |
| 1116 | case err := <-bodyWriter.resc: |
| 1117 | // Prefer the read loop's response, if available. Issue 16102. |
| 1118 | select { |
| 1119 | case re := <-readLoopResCh: |
| 1120 | return handleReadLoopResponse(re) |
| 1121 | default: |
| 1122 | } |
| 1123 | if err != nil { |
| 1124 | cc.forgetStreamID(cs.ID) |
| 1125 | return nil, cs.getStartedWrite(), err |
| 1126 | } |
| 1127 | bodyWritten = true |
| 1128 | if d := cc.responseHeaderTimeout(); d != 0 { |
| 1129 | timer := time.NewTimer(d) |
| 1130 | defer timer.Stop() |
| 1131 | respHeaderTimer = timer.C |
| 1132 | } |
| 1133 | } |
| 1134 | } |
| 1135 | } |
| 1136 | |
| 1137 | // awaitOpenSlotForRequest waits until len(streams) < maxConcurrentStreams. |
| 1138 | // Must hold cc.mu. |
| 1139 | func (cc *ClientConn) awaitOpenSlotForRequest(req *http.Request) error { |
| 1140 | var waitingForConn chan struct{} |
| 1141 | var waitingForConnErr error // guarded by cc.mu |
| 1142 | for { |
| 1143 | cc.lastActive = time.Now() |
| 1144 | if cc.closed || !cc.canTakeNewRequestLocked() { |
| 1145 | if waitingForConn != nil { |
| 1146 | close(waitingForConn) |
| 1147 | } |
| 1148 | return errClientConnUnusable |
| 1149 | } |
| 1150 | if int64(len(cc.streams))+1 <= int64(cc.maxConcurrentStreams) { |
| 1151 | if waitingForConn != nil { |
| 1152 | close(waitingForConn) |
| 1153 | } |
| 1154 | return nil |
| 1155 | } |
| 1156 | // Unfortunately, we cannot wait on a condition variable and channel at |
| 1157 | // the same time, so instead, we spin up a goroutine to check if the |
| 1158 | // request is canceled while we wait for a slot to open in the connection. |
| 1159 | if waitingForConn == nil { |
| 1160 | waitingForConn = make(chan struct{}) |
| 1161 | go func() { |
| 1162 | if err := awaitRequestCancel(req, waitingForConn); err != nil { |
| 1163 | cc.mu.Lock() |
| 1164 | waitingForConnErr = err |
| 1165 | cc.cond.Broadcast() |
| 1166 | cc.mu.Unlock() |
| 1167 | } |
| 1168 | }() |
| 1169 | } |
| 1170 | cc.pendingRequests++ |
| 1171 | cc.cond.Wait() |
| 1172 | cc.pendingRequests-- |
| 1173 | if waitingForConnErr != nil { |
| 1174 | return waitingForConnErr |
| 1175 | } |
| 1176 | } |
| 1177 | } |
| 1178 | |
| 1179 | // requires cc.wmu be held |
| 1180 | func (cc *ClientConn) writeHeaders(streamID uint32, endStream bool, maxFrameSize int, hdrs []byte) error { |
| 1181 | first := true // first frame written (HEADERS is first, then CONTINUATION) |
| 1182 | for len(hdrs) > 0 && cc.werr == nil { |
| 1183 | chunk := hdrs |
| 1184 | if len(chunk) > maxFrameSize { |
| 1185 | chunk = chunk[:maxFrameSize] |
| 1186 | } |
| 1187 | hdrs = hdrs[len(chunk):] |
| 1188 | endHeaders := len(hdrs) == 0 |
| 1189 | if first { |
| 1190 | cc.fr.WriteHeaders(HeadersFrameParam{ |
| 1191 | StreamID: streamID, |
| 1192 | BlockFragment: chunk, |
| 1193 | EndStream: endStream, |
| 1194 | EndHeaders: endHeaders, |
| 1195 | }) |
| 1196 | first = false |
| 1197 | } else { |
| 1198 | cc.fr.WriteContinuation(streamID, endHeaders, chunk) |
| 1199 | } |
| 1200 | } |
| 1201 | // TODO(bradfitz): this Flush could potentially block (as |
| 1202 | // could the WriteHeaders call(s) above), which means they |
| 1203 | // wouldn't respond to Request.Cancel being readable. That's |
| 1204 | // rare, but this should probably be in a goroutine. |
| 1205 | cc.bw.Flush() |
| 1206 | return cc.werr |
| 1207 | } |
| 1208 | |
| 1209 | // internal error values; they don't escape to callers |
| 1210 | var ( |
| 1211 | // abort request body write; don't send cancel |
| 1212 | errStopReqBodyWrite = errors.New("http2: aborting request body write") |
| 1213 | |
| 1214 | // abort request body write, but send stream reset of cancel. |
| 1215 | errStopReqBodyWriteAndCancel = errors.New("http2: canceling request") |
| 1216 | ) |
| 1217 | |
| 1218 | func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (err error) { |
| 1219 | cc := cs.cc |
| 1220 | sentEnd := false // whether we sent the final DATA frame w/ END_STREAM |
| 1221 | buf := cc.frameScratchBuffer() |
| 1222 | defer cc.putFrameScratchBuffer(buf) |
| 1223 | |
| 1224 | defer func() { |
| 1225 | traceWroteRequest(cs.trace, err) |
| 1226 | // TODO: write h12Compare test showing whether |
| 1227 | // Request.Body is closed by the Transport, |
| 1228 | // and in multiple cases: server replies <=299 and >299 |
| 1229 | // while still writing request body |
| 1230 | cerr := bodyCloser.Close() |
| 1231 | if err == nil { |
| 1232 | err = cerr |
| 1233 | } |
| 1234 | }() |
| 1235 | |
| 1236 | req := cs.req |
| 1237 | hasTrailers := req.Trailer != nil |
| 1238 | |
| 1239 | var sawEOF bool |
| 1240 | for !sawEOF { |
| 1241 | n, err := body.Read(buf) |
| 1242 | if err == io.EOF { |
| 1243 | sawEOF = true |
| 1244 | err = nil |
| 1245 | } else if err != nil { |
| 1246 | cc.writeStreamReset(cs.ID, ErrCodeCancel, err) |
| 1247 | return err |
| 1248 | } |
| 1249 | |
| 1250 | remain := buf[:n] |
| 1251 | for len(remain) > 0 && err == nil { |
| 1252 | var allowed int32 |
| 1253 | allowed, err = cs.awaitFlowControl(len(remain)) |
| 1254 | switch { |
| 1255 | case err == errStopReqBodyWrite: |
| 1256 | return err |
| 1257 | case err == errStopReqBodyWriteAndCancel: |
| 1258 | cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) |
| 1259 | return err |
| 1260 | case err != nil: |
| 1261 | return err |
| 1262 | } |
| 1263 | cc.wmu.Lock() |
| 1264 | data := remain[:allowed] |
| 1265 | remain = remain[allowed:] |
| 1266 | sentEnd = sawEOF && len(remain) == 0 && !hasTrailers |
| 1267 | err = cc.fr.WriteData(cs.ID, sentEnd, data) |
| 1268 | if err == nil { |
| 1269 | // TODO(bradfitz): this flush is for latency, not bandwidth. |
| 1270 | // Most requests won't need this. Make this opt-in or |
| 1271 | // opt-out? Use some heuristic on the body type? Nagel-like |
| 1272 | // timers? Based on 'n'? Only last chunk of this for loop, |
| 1273 | // unless flow control tokens are low? For now, always. |
| 1274 | // If we change this, see comment below. |
| 1275 | err = cc.bw.Flush() |
| 1276 | } |
| 1277 | cc.wmu.Unlock() |
| 1278 | } |
| 1279 | if err != nil { |
| 1280 | return err |
| 1281 | } |
| 1282 | } |
| 1283 | |
| 1284 | if sentEnd { |
| 1285 | // Already sent END_STREAM (which implies we have no |
| 1286 | // trailers) and flushed, because currently all |
| 1287 | // WriteData frames above get a flush. So we're done. |
| 1288 | return nil |
| 1289 | } |
| 1290 | |
| 1291 | var trls []byte |
| 1292 | if hasTrailers { |
| 1293 | cc.mu.Lock() |
| 1294 | trls, err = cc.encodeTrailers(req) |
| 1295 | cc.mu.Unlock() |
| 1296 | if err != nil { |
| 1297 | cc.writeStreamReset(cs.ID, ErrCodeInternal, err) |
| 1298 | cc.forgetStreamID(cs.ID) |
| 1299 | return err |
| 1300 | } |
| 1301 | } |
| 1302 | |
| 1303 | cc.mu.Lock() |
| 1304 | maxFrameSize := int(cc.maxFrameSize) |
| 1305 | cc.mu.Unlock() |
| 1306 | |
| 1307 | cc.wmu.Lock() |
| 1308 | defer cc.wmu.Unlock() |
| 1309 | |
| 1310 | // Two ways to send END_STREAM: either with trailers, or |
| 1311 | // with an empty DATA frame. |
| 1312 | if len(trls) > 0 { |
| 1313 | err = cc.writeHeaders(cs.ID, true, maxFrameSize, trls) |
| 1314 | } else { |
| 1315 | err = cc.fr.WriteData(cs.ID, true, nil) |
| 1316 | } |
| 1317 | if ferr := cc.bw.Flush(); ferr != nil && err == nil { |
| 1318 | err = ferr |
| 1319 | } |
| 1320 | return err |
| 1321 | } |
| 1322 | |
| 1323 | // awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow |
| 1324 | // control tokens from the server. |
| 1325 | // It returns either the non-zero number of tokens taken or an error |
| 1326 | // if the stream is dead. |
| 1327 | func (cs *clientStream) awaitFlowControl(maxBytes int) (taken int32, err error) { |
| 1328 | cc := cs.cc |
| 1329 | cc.mu.Lock() |
| 1330 | defer cc.mu.Unlock() |
| 1331 | for { |
| 1332 | if cc.closed { |
| 1333 | return 0, errClientConnClosed |
| 1334 | } |
| 1335 | if cs.stopReqBody != nil { |
| 1336 | return 0, cs.stopReqBody |
| 1337 | } |
| 1338 | if err := cs.checkResetOrDone(); err != nil { |
| 1339 | return 0, err |
| 1340 | } |
| 1341 | if a := cs.flow.available(); a > 0 { |
| 1342 | take := a |
| 1343 | if int(take) > maxBytes { |
| 1344 | |
| 1345 | take = int32(maxBytes) // can't truncate int; take is int32 |
| 1346 | } |
| 1347 | if take > int32(cc.maxFrameSize) { |
| 1348 | take = int32(cc.maxFrameSize) |
| 1349 | } |
| 1350 | cs.flow.take(take) |
| 1351 | return take, nil |
| 1352 | } |
| 1353 | cc.cond.Wait() |
| 1354 | } |
| 1355 | } |
| 1356 | |
| 1357 | type badStringError struct { |
| 1358 | what string |
| 1359 | str string |
| 1360 | } |
| 1361 | |
| 1362 | func (e *badStringError) Error() string { return fmt.Sprintf("%s %q", e.what, e.str) } |
| 1363 | |
| 1364 | // requires cc.mu be held. |
| 1365 | func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) { |
| 1366 | cc.hbuf.Reset() |
| 1367 | |
| 1368 | host := req.Host |
| 1369 | if host == "" { |
| 1370 | host = req.URL.Host |
| 1371 | } |
| 1372 | host, err := httpguts.PunycodeHostPort(host) |
| 1373 | if err != nil { |
| 1374 | return nil, err |
| 1375 | } |
| 1376 | |
| 1377 | var path string |
| 1378 | if req.Method != "CONNECT" { |
| 1379 | path = req.URL.RequestURI() |
| 1380 | if !validPseudoPath(path) { |
| 1381 | orig := path |
| 1382 | path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host) |
| 1383 | if !validPseudoPath(path) { |
| 1384 | if req.URL.Opaque != "" { |
| 1385 | return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque) |
| 1386 | } else { |
| 1387 | return nil, fmt.Errorf("invalid request :path %q", orig) |
| 1388 | } |
| 1389 | } |
| 1390 | } |
| 1391 | } |
| 1392 | |
| 1393 | // Check for any invalid headers and return an error before we |
| 1394 | // potentially pollute our hpack state. (We want to be able to |
| 1395 | // continue to reuse the hpack encoder for future requests) |
| 1396 | for k, vv := range req.Header { |
| 1397 | if !httpguts.ValidHeaderFieldName(k) { |
| 1398 | return nil, fmt.Errorf("invalid HTTP header name %q", k) |
| 1399 | } |
| 1400 | for _, v := range vv { |
| 1401 | if !httpguts.ValidHeaderFieldValue(v) { |
| 1402 | return nil, fmt.Errorf("invalid HTTP header value %q for header %q", v, k) |
| 1403 | } |
| 1404 | } |
| 1405 | } |
| 1406 | |
| 1407 | enumerateHeaders := func(f func(name, value string)) { |
| 1408 | // 8.1.2.3 Request Pseudo-Header Fields |
| 1409 | // The :path pseudo-header field includes the path and query parts of the |
| 1410 | // target URI (the path-absolute production and optionally a '?' character |
| 1411 | // followed by the query production (see Sections 3.3 and 3.4 of |
| 1412 | // [RFC3986]). |
| 1413 | f(":authority", host) |
| 1414 | m := req.Method |
| 1415 | if m == "" { |
| 1416 | m = http.MethodGet |
| 1417 | } |
| 1418 | f(":method", m) |
| 1419 | if req.Method != "CONNECT" { |
| 1420 | f(":path", path) |
| 1421 | f(":scheme", req.URL.Scheme) |
| 1422 | } |
| 1423 | if trailers != "" { |
| 1424 | f("trailer", trailers) |
| 1425 | } |
| 1426 | |
| 1427 | var didUA bool |
| 1428 | for k, vv := range req.Header { |
| 1429 | if strings.EqualFold(k, "host") || strings.EqualFold(k, "content-length") { |
| 1430 | // Host is :authority, already sent. |
| 1431 | // Content-Length is automatic, set below. |
| 1432 | continue |
| 1433 | } else if strings.EqualFold(k, "connection") || strings.EqualFold(k, "proxy-connection") || |
| 1434 | strings.EqualFold(k, "transfer-encoding") || strings.EqualFold(k, "upgrade") || |
| 1435 | strings.EqualFold(k, "keep-alive") { |
| 1436 | // Per 8.1.2.2 Connection-Specific Header |
| 1437 | // Fields, don't send connection-specific |
| 1438 | // fields. We have already checked if any |
| 1439 | // are error-worthy so just ignore the rest. |
| 1440 | continue |
| 1441 | } else if strings.EqualFold(k, "user-agent") { |
| 1442 | // Match Go's http1 behavior: at most one |
| 1443 | // User-Agent. If set to nil or empty string, |
| 1444 | // then omit it. Otherwise if not mentioned, |
| 1445 | // include the default (below). |
| 1446 | didUA = true |
| 1447 | if len(vv) < 1 { |
| 1448 | continue |
| 1449 | } |
| 1450 | vv = vv[:1] |
| 1451 | if vv[0] == "" { |
| 1452 | continue |
| 1453 | } |
| 1454 | |
| 1455 | } |
| 1456 | |
| 1457 | for _, v := range vv { |
| 1458 | f(k, v) |
| 1459 | } |
| 1460 | } |
| 1461 | if shouldSendReqContentLength(req.Method, contentLength) { |
| 1462 | f("content-length", strconv.FormatInt(contentLength, 10)) |
| 1463 | } |
| 1464 | if addGzipHeader { |
| 1465 | f("accept-encoding", "gzip") |
| 1466 | } |
| 1467 | if !didUA { |
| 1468 | f("user-agent", defaultUserAgent) |
| 1469 | } |
| 1470 | } |
| 1471 | |
| 1472 | // Do a first pass over the headers counting bytes to ensure |
| 1473 | // we don't exceed cc.peerMaxHeaderListSize. This is done as a |
| 1474 | // separate pass before encoding the headers to prevent |
| 1475 | // modifying the hpack state. |
| 1476 | hlSize := uint64(0) |
| 1477 | enumerateHeaders(func(name, value string) { |
| 1478 | hf := hpack.HeaderField{Name: name, Value: value} |
| 1479 | hlSize += uint64(hf.Size()) |
| 1480 | }) |
| 1481 | |
| 1482 | if hlSize > cc.peerMaxHeaderListSize { |
| 1483 | return nil, errRequestHeaderListSize |
| 1484 | } |
| 1485 | |
| 1486 | trace := httptrace.ContextClientTrace(req.Context()) |
| 1487 | traceHeaders := traceHasWroteHeaderField(trace) |
| 1488 | |
| 1489 | // Header list size is ok. Write the headers. |
| 1490 | enumerateHeaders(func(name, value string) { |
| 1491 | name = strings.ToLower(name) |
| 1492 | cc.writeHeader(name, value) |
| 1493 | if traceHeaders { |
| 1494 | traceWroteHeaderField(trace, name, value) |
| 1495 | } |
| 1496 | }) |
| 1497 | |
| 1498 | return cc.hbuf.Bytes(), nil |
| 1499 | } |
| 1500 | |
| 1501 | // shouldSendReqContentLength reports whether the http2.Transport should send |
| 1502 | // a "content-length" request header. This logic is basically a copy of the net/http |
| 1503 | // transferWriter.shouldSendContentLength. |
| 1504 | // The contentLength is the corrected contentLength (so 0 means actually 0, not unknown). |
| 1505 | // -1 means unknown. |
| 1506 | func shouldSendReqContentLength(method string, contentLength int64) bool { |
| 1507 | if contentLength > 0 { |
| 1508 | return true |
| 1509 | } |
| 1510 | if contentLength < 0 { |
| 1511 | return false |
| 1512 | } |
| 1513 | // For zero bodies, whether we send a content-length depends on the method. |
| 1514 | // It also kinda doesn't matter for http2 either way, with END_STREAM. |
| 1515 | switch method { |
| 1516 | case "POST", "PUT", "PATCH": |
| 1517 | return true |
| 1518 | default: |
| 1519 | return false |
| 1520 | } |
| 1521 | } |
| 1522 | |
| 1523 | // requires cc.mu be held. |
| 1524 | func (cc *ClientConn) encodeTrailers(req *http.Request) ([]byte, error) { |
| 1525 | cc.hbuf.Reset() |
| 1526 | |
| 1527 | hlSize := uint64(0) |
| 1528 | for k, vv := range req.Trailer { |
| 1529 | for _, v := range vv { |
| 1530 | hf := hpack.HeaderField{Name: k, Value: v} |
| 1531 | hlSize += uint64(hf.Size()) |
| 1532 | } |
| 1533 | } |
| 1534 | if hlSize > cc.peerMaxHeaderListSize { |
| 1535 | return nil, errRequestHeaderListSize |
| 1536 | } |
| 1537 | |
| 1538 | for k, vv := range req.Trailer { |
| 1539 | // Transfer-Encoding, etc.. have already been filtered at the |
| 1540 | // start of RoundTrip |
| 1541 | lowKey := strings.ToLower(k) |
| 1542 | for _, v := range vv { |
| 1543 | cc.writeHeader(lowKey, v) |
| 1544 | } |
| 1545 | } |
| 1546 | return cc.hbuf.Bytes(), nil |
| 1547 | } |
| 1548 | |
| 1549 | func (cc *ClientConn) writeHeader(name, value string) { |
| 1550 | if VerboseLogs { |
| 1551 | log.Printf("http2: Transport encoding header %q = %q", name, value) |
| 1552 | } |
| 1553 | cc.henc.WriteField(hpack.HeaderField{Name: name, Value: value}) |
| 1554 | } |
| 1555 | |
| 1556 | type resAndError struct { |
| 1557 | res *http.Response |
| 1558 | err error |
| 1559 | } |
| 1560 | |
| 1561 | // requires cc.mu be held. |
| 1562 | func (cc *ClientConn) newStream() *clientStream { |
| 1563 | cs := &clientStream{ |
| 1564 | cc: cc, |
| 1565 | ID: cc.nextStreamID, |
| 1566 | resc: make(chan resAndError, 1), |
| 1567 | peerReset: make(chan struct{}), |
| 1568 | done: make(chan struct{}), |
| 1569 | } |
| 1570 | cs.flow.add(int32(cc.initialWindowSize)) |
| 1571 | cs.flow.setConnFlow(&cc.flow) |
| 1572 | cs.inflow.add(transportDefaultStreamFlow) |
| 1573 | cs.inflow.setConnFlow(&cc.inflow) |
| 1574 | cc.nextStreamID += 2 |
| 1575 | cc.streams[cs.ID] = cs |
| 1576 | return cs |
| 1577 | } |
| 1578 | |
| 1579 | func (cc *ClientConn) forgetStreamID(id uint32) { |
| 1580 | cc.streamByID(id, true) |
| 1581 | } |
| 1582 | |
| 1583 | func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream { |
| 1584 | cc.mu.Lock() |
| 1585 | defer cc.mu.Unlock() |
| 1586 | cs := cc.streams[id] |
| 1587 | if andRemove && cs != nil && !cc.closed { |
| 1588 | cc.lastActive = time.Now() |
| 1589 | delete(cc.streams, id) |
| 1590 | if len(cc.streams) == 0 && cc.idleTimer != nil { |
| 1591 | cc.idleTimer.Reset(cc.idleTimeout) |
| 1592 | } |
| 1593 | close(cs.done) |
| 1594 | // Wake up checkResetOrDone via clientStream.awaitFlowControl and |
| 1595 | // wake up RoundTrip if there is a pending request. |
| 1596 | cc.cond.Broadcast() |
| 1597 | } |
| 1598 | return cs |
| 1599 | } |
| 1600 | |
| 1601 | // clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop. |
| 1602 | type clientConnReadLoop struct { |
| 1603 | cc *ClientConn |
| 1604 | closeWhenIdle bool |
| 1605 | } |
| 1606 | |
| 1607 | // readLoop runs in its own goroutine and reads and dispatches frames. |
| 1608 | func (cc *ClientConn) readLoop() { |
| 1609 | rl := &clientConnReadLoop{cc: cc} |
| 1610 | defer rl.cleanup() |
| 1611 | cc.readerErr = rl.run() |
| 1612 | if ce, ok := cc.readerErr.(ConnectionError); ok { |
| 1613 | cc.wmu.Lock() |
| 1614 | cc.fr.WriteGoAway(0, ErrCode(ce), nil) |
| 1615 | cc.wmu.Unlock() |
| 1616 | } |
| 1617 | } |
| 1618 | |
| 1619 | // GoAwayError is returned by the Transport when the server closes the |
| 1620 | // TCP connection after sending a GOAWAY frame. |
| 1621 | type GoAwayError struct { |
| 1622 | LastStreamID uint32 |
| 1623 | ErrCode ErrCode |
| 1624 | DebugData string |
| 1625 | } |
| 1626 | |
| 1627 | func (e GoAwayError) Error() string { |
| 1628 | return fmt.Sprintf("http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q", |
| 1629 | e.LastStreamID, e.ErrCode, e.DebugData) |
| 1630 | } |
| 1631 | |
| 1632 | func isEOFOrNetReadError(err error) bool { |
| 1633 | if err == io.EOF { |
| 1634 | return true |
| 1635 | } |
| 1636 | ne, ok := err.(*net.OpError) |
| 1637 | return ok && ne.Op == "read" |
| 1638 | } |
| 1639 | |
| 1640 | func (rl *clientConnReadLoop) cleanup() { |
| 1641 | cc := rl.cc |
| 1642 | defer cc.tconn.Close() |
| 1643 | defer cc.t.connPool().MarkDead(cc) |
| 1644 | defer close(cc.readerDone) |
| 1645 | |
| 1646 | if cc.idleTimer != nil { |
| 1647 | cc.idleTimer.Stop() |
| 1648 | } |
| 1649 | |
| 1650 | // Close any response bodies if the server closes prematurely. |
| 1651 | // TODO: also do this if we've written the headers but not |
| 1652 | // gotten a response yet. |
| 1653 | err := cc.readerErr |
| 1654 | cc.mu.Lock() |
| 1655 | if cc.goAway != nil && isEOFOrNetReadError(err) { |
| 1656 | err = GoAwayError{ |
| 1657 | LastStreamID: cc.goAway.LastStreamID, |
| 1658 | ErrCode: cc.goAway.ErrCode, |
| 1659 | DebugData: cc.goAwayDebug, |
| 1660 | } |
| 1661 | } else if err == io.EOF { |
| 1662 | err = io.ErrUnexpectedEOF |
| 1663 | } |
| 1664 | for _, cs := range cc.streams { |
| 1665 | cs.bufPipe.CloseWithError(err) // no-op if already closed |
| 1666 | select { |
| 1667 | case cs.resc <- resAndError{err: err}: |
| 1668 | default: |
| 1669 | } |
| 1670 | close(cs.done) |
| 1671 | } |
| 1672 | cc.closed = true |
| 1673 | cc.cond.Broadcast() |
| 1674 | cc.mu.Unlock() |
| 1675 | } |
| 1676 | |
| 1677 | func (rl *clientConnReadLoop) run() error { |
| 1678 | cc := rl.cc |
| 1679 | rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse |
| 1680 | gotReply := false // ever saw a HEADERS reply |
| 1681 | gotSettings := false |
| 1682 | for { |
| 1683 | f, err := cc.fr.ReadFrame() |
| 1684 | if err != nil { |
| 1685 | cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err) |
| 1686 | } |
| 1687 | if se, ok := err.(StreamError); ok { |
| 1688 | if cs := cc.streamByID(se.StreamID, false); cs != nil { |
| 1689 | cs.cc.writeStreamReset(cs.ID, se.Code, err) |
| 1690 | cs.cc.forgetStreamID(cs.ID) |
| 1691 | if se.Cause == nil { |
| 1692 | se.Cause = cc.fr.errDetail |
| 1693 | } |
| 1694 | rl.endStreamError(cs, se) |
| 1695 | } |
| 1696 | continue |
| 1697 | } else if err != nil { |
| 1698 | return err |
| 1699 | } |
| 1700 | if VerboseLogs { |
| 1701 | cc.vlogf("http2: Transport received %s", summarizeFrame(f)) |
| 1702 | } |
| 1703 | if !gotSettings { |
| 1704 | if _, ok := f.(*SettingsFrame); !ok { |
| 1705 | cc.logf("protocol error: received %T before a SETTINGS frame", f) |
| 1706 | return ConnectionError(ErrCodeProtocol) |
| 1707 | } |
| 1708 | gotSettings = true |
| 1709 | } |
| 1710 | maybeIdle := false // whether frame might transition us to idle |
| 1711 | |
| 1712 | switch f := f.(type) { |
| 1713 | case *MetaHeadersFrame: |
| 1714 | err = rl.processHeaders(f) |
| 1715 | maybeIdle = true |
| 1716 | gotReply = true |
| 1717 | case *DataFrame: |
| 1718 | err = rl.processData(f) |
| 1719 | maybeIdle = true |
| 1720 | case *GoAwayFrame: |
| 1721 | err = rl.processGoAway(f) |
| 1722 | maybeIdle = true |
| 1723 | case *RSTStreamFrame: |
| 1724 | err = rl.processResetStream(f) |
| 1725 | maybeIdle = true |
| 1726 | case *SettingsFrame: |
| 1727 | err = rl.processSettings(f) |
| 1728 | case *PushPromiseFrame: |
| 1729 | err = rl.processPushPromise(f) |
| 1730 | case *WindowUpdateFrame: |
| 1731 | err = rl.processWindowUpdate(f) |
| 1732 | case *PingFrame: |
| 1733 | err = rl.processPing(f) |
| 1734 | default: |
| 1735 | cc.logf("Transport: unhandled response frame type %T", f) |
| 1736 | } |
| 1737 | if err != nil { |
| 1738 | if VerboseLogs { |
| 1739 | cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, summarizeFrame(f), err) |
| 1740 | } |
| 1741 | return err |
| 1742 | } |
| 1743 | if rl.closeWhenIdle && gotReply && maybeIdle { |
| 1744 | cc.closeIfIdle() |
| 1745 | } |
| 1746 | } |
| 1747 | } |
| 1748 | |
| 1749 | func (rl *clientConnReadLoop) processHeaders(f *MetaHeadersFrame) error { |
| 1750 | cc := rl.cc |
| 1751 | cs := cc.streamByID(f.StreamID, false) |
| 1752 | if cs == nil { |
| 1753 | // We'd get here if we canceled a request while the |
| 1754 | // server had its response still in flight. So if this |
| 1755 | // was just something we canceled, ignore it. |
| 1756 | return nil |
| 1757 | } |
| 1758 | if f.StreamEnded() { |
| 1759 | // Issue 20521: If the stream has ended, streamByID() causes |
| 1760 | // clientStream.done to be closed, which causes the request's bodyWriter |
| 1761 | // to be closed with an errStreamClosed, which may be received by |
| 1762 | // clientConn.RoundTrip before the result of processing these headers. |
| 1763 | // Deferring stream closure allows the header processing to occur first. |
| 1764 | // clientConn.RoundTrip may still receive the bodyWriter error first, but |
| 1765 | // the fix for issue 16102 prioritises any response. |
| 1766 | // |
| 1767 | // Issue 22413: If there is no request body, we should close the |
| 1768 | // stream before writing to cs.resc so that the stream is closed |
| 1769 | // immediately once RoundTrip returns. |
| 1770 | if cs.req.Body != nil { |
| 1771 | defer cc.forgetStreamID(f.StreamID) |
| 1772 | } else { |
| 1773 | cc.forgetStreamID(f.StreamID) |
| 1774 | } |
| 1775 | } |
| 1776 | if !cs.firstByte { |
| 1777 | if cs.trace != nil { |
| 1778 | // TODO(bradfitz): move first response byte earlier, |
| 1779 | // when we first read the 9 byte header, not waiting |
| 1780 | // until all the HEADERS+CONTINUATION frames have been |
| 1781 | // merged. This works for now. |
| 1782 | traceFirstResponseByte(cs.trace) |
| 1783 | } |
| 1784 | cs.firstByte = true |
| 1785 | } |
| 1786 | if !cs.pastHeaders { |
| 1787 | cs.pastHeaders = true |
| 1788 | } else { |
| 1789 | return rl.processTrailers(cs, f) |
| 1790 | } |
| 1791 | |
| 1792 | res, err := rl.handleResponse(cs, f) |
| 1793 | if err != nil { |
| 1794 | if _, ok := err.(ConnectionError); ok { |
| 1795 | return err |
| 1796 | } |
| 1797 | // Any other error type is a stream error. |
| 1798 | cs.cc.writeStreamReset(f.StreamID, ErrCodeProtocol, err) |
| 1799 | cc.forgetStreamID(cs.ID) |
| 1800 | cs.resc <- resAndError{err: err} |
| 1801 | return nil // return nil from process* funcs to keep conn alive |
| 1802 | } |
| 1803 | if res == nil { |
| 1804 | // (nil, nil) special case. See handleResponse docs. |
| 1805 | return nil |
| 1806 | } |
| 1807 | cs.resTrailer = &res.Trailer |
| 1808 | cs.resc <- resAndError{res: res} |
| 1809 | return nil |
| 1810 | } |
| 1811 | |
| 1812 | // may return error types nil, or ConnectionError. Any other error value |
| 1813 | // is a StreamError of type ErrCodeProtocol. The returned error in that case |
| 1814 | // is the detail. |
| 1815 | // |
| 1816 | // As a special case, handleResponse may return (nil, nil) to skip the |
| 1817 | // frame (currently only used for 1xx responses). |
| 1818 | func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFrame) (*http.Response, error) { |
| 1819 | if f.Truncated { |
| 1820 | return nil, errResponseHeaderListSize |
| 1821 | } |
| 1822 | |
| 1823 | status := f.PseudoValue("status") |
| 1824 | if status == "" { |
| 1825 | return nil, errors.New("malformed response from server: missing status pseudo header") |
| 1826 | } |
| 1827 | statusCode, err := strconv.Atoi(status) |
| 1828 | if err != nil { |
| 1829 | return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header") |
| 1830 | } |
| 1831 | |
| 1832 | header := make(http.Header) |
| 1833 | res := &http.Response{ |
| 1834 | Proto: "HTTP/2.0", |
| 1835 | ProtoMajor: 2, |
| 1836 | Header: header, |
| 1837 | StatusCode: statusCode, |
| 1838 | Status: status + " " + http.StatusText(statusCode), |
| 1839 | } |
| 1840 | for _, hf := range f.RegularFields() { |
| 1841 | key := http.CanonicalHeaderKey(hf.Name) |
| 1842 | if key == "Trailer" { |
| 1843 | t := res.Trailer |
| 1844 | if t == nil { |
| 1845 | t = make(http.Header) |
| 1846 | res.Trailer = t |
| 1847 | } |
| 1848 | foreachHeaderElement(hf.Value, func(v string) { |
| 1849 | t[http.CanonicalHeaderKey(v)] = nil |
| 1850 | }) |
| 1851 | } else { |
| 1852 | header[key] = append(header[key], hf.Value) |
| 1853 | } |
| 1854 | } |
| 1855 | |
| 1856 | if statusCode >= 100 && statusCode <= 199 { |
| 1857 | cs.num1xx++ |
| 1858 | const max1xxResponses = 5 // arbitrary bound on number of informational responses, same as net/http |
| 1859 | if cs.num1xx > max1xxResponses { |
| 1860 | return nil, errors.New("http2: too many 1xx informational responses") |
| 1861 | } |
| 1862 | if fn := cs.get1xxTraceFunc(); fn != nil { |
| 1863 | if err := fn(statusCode, textproto.MIMEHeader(header)); err != nil { |
| 1864 | return nil, err |
| 1865 | } |
| 1866 | } |
| 1867 | if statusCode == 100 { |
| 1868 | traceGot100Continue(cs.trace) |
| 1869 | if cs.on100 != nil { |
| 1870 | cs.on100() // forces any write delay timer to fire |
| 1871 | } |
| 1872 | } |
| 1873 | cs.pastHeaders = false // do it all again |
| 1874 | return nil, nil |
| 1875 | } |
| 1876 | |
| 1877 | streamEnded := f.StreamEnded() |
| 1878 | isHead := cs.req.Method == "HEAD" |
| 1879 | if !streamEnded || isHead { |
| 1880 | res.ContentLength = -1 |
| 1881 | if clens := res.Header["Content-Length"]; len(clens) == 1 { |
| 1882 | if clen64, err := strconv.ParseInt(clens[0], 10, 64); err == nil { |
| 1883 | res.ContentLength = clen64 |
| 1884 | } else { |
| 1885 | // TODO: care? unlike http/1, it won't mess up our framing, so it's |
| 1886 | // more safe smuggling-wise to ignore. |
| 1887 | } |
| 1888 | } else if len(clens) > 1 { |
| 1889 | // TODO: care? unlike http/1, it won't mess up our framing, so it's |
| 1890 | // more safe smuggling-wise to ignore. |
| 1891 | } |
| 1892 | } |
| 1893 | |
| 1894 | if streamEnded || isHead { |
| 1895 | res.Body = noBody |
| 1896 | return res, nil |
| 1897 | } |
| 1898 | |
| 1899 | cs.bufPipe = pipe{b: &dataBuffer{expected: res.ContentLength}} |
| 1900 | cs.bytesRemain = res.ContentLength |
| 1901 | res.Body = transportResponseBody{cs} |
| 1902 | go cs.awaitRequestCancel(cs.req) |
| 1903 | |
| 1904 | if cs.requestedGzip && res.Header.Get("Content-Encoding") == "gzip" { |
| 1905 | res.Header.Del("Content-Encoding") |
| 1906 | res.Header.Del("Content-Length") |
| 1907 | res.ContentLength = -1 |
| 1908 | res.Body = &gzipReader{body: res.Body} |
| 1909 | res.Uncompressed = true |
| 1910 | } |
| 1911 | return res, nil |
| 1912 | } |
| 1913 | |
| 1914 | func (rl *clientConnReadLoop) processTrailers(cs *clientStream, f *MetaHeadersFrame) error { |
| 1915 | if cs.pastTrailers { |
| 1916 | // Too many HEADERS frames for this stream. |
| 1917 | return ConnectionError(ErrCodeProtocol) |
| 1918 | } |
| 1919 | cs.pastTrailers = true |
| 1920 | if !f.StreamEnded() { |
| 1921 | // We expect that any headers for trailers also |
| 1922 | // has END_STREAM. |
| 1923 | return ConnectionError(ErrCodeProtocol) |
| 1924 | } |
| 1925 | if len(f.PseudoFields()) > 0 { |
| 1926 | // No pseudo header fields are defined for trailers. |
| 1927 | // TODO: ConnectionError might be overly harsh? Check. |
| 1928 | return ConnectionError(ErrCodeProtocol) |
| 1929 | } |
| 1930 | |
| 1931 | trailer := make(http.Header) |
| 1932 | for _, hf := range f.RegularFields() { |
| 1933 | key := http.CanonicalHeaderKey(hf.Name) |
| 1934 | trailer[key] = append(trailer[key], hf.Value) |
| 1935 | } |
| 1936 | cs.trailer = trailer |
| 1937 | |
| 1938 | rl.endStream(cs) |
| 1939 | return nil |
| 1940 | } |
| 1941 | |
| 1942 | // transportResponseBody is the concrete type of Transport.RoundTrip's |
| 1943 | // Response.Body. It is an io.ReadCloser. On Read, it reads from cs.body. |
| 1944 | // On Close it sends RST_STREAM if EOF wasn't already seen. |
| 1945 | type transportResponseBody struct { |
| 1946 | cs *clientStream |
| 1947 | } |
| 1948 | |
| 1949 | func (b transportResponseBody) Read(p []byte) (n int, err error) { |
| 1950 | cs := b.cs |
| 1951 | cc := cs.cc |
| 1952 | |
| 1953 | if cs.readErr != nil { |
| 1954 | return 0, cs.readErr |
| 1955 | } |
| 1956 | n, err = b.cs.bufPipe.Read(p) |
| 1957 | if cs.bytesRemain != -1 { |
| 1958 | if int64(n) > cs.bytesRemain { |
| 1959 | n = int(cs.bytesRemain) |
| 1960 | if err == nil { |
| 1961 | err = errors.New("net/http: server replied with more than declared Content-Length; truncated") |
| 1962 | cc.writeStreamReset(cs.ID, ErrCodeProtocol, err) |
| 1963 | } |
| 1964 | cs.readErr = err |
| 1965 | return int(cs.bytesRemain), err |
| 1966 | } |
| 1967 | cs.bytesRemain -= int64(n) |
| 1968 | if err == io.EOF && cs.bytesRemain > 0 { |
| 1969 | err = io.ErrUnexpectedEOF |
| 1970 | cs.readErr = err |
| 1971 | return n, err |
| 1972 | } |
| 1973 | } |
| 1974 | if n == 0 { |
| 1975 | // No flow control tokens to send back. |
| 1976 | return |
| 1977 | } |
| 1978 | |
| 1979 | cc.mu.Lock() |
| 1980 | defer cc.mu.Unlock() |
| 1981 | |
| 1982 | var connAdd, streamAdd int32 |
| 1983 | // Check the conn-level first, before the stream-level. |
| 1984 | if v := cc.inflow.available(); v < transportDefaultConnFlow/2 { |
| 1985 | connAdd = transportDefaultConnFlow - v |
| 1986 | cc.inflow.add(connAdd) |
| 1987 | } |
| 1988 | if err == nil { // No need to refresh if the stream is over or failed. |
| 1989 | // Consider any buffered body data (read from the conn but not |
| 1990 | // consumed by the client) when computing flow control for this |
| 1991 | // stream. |
| 1992 | v := int(cs.inflow.available()) + cs.bufPipe.Len() |
| 1993 | if v < transportDefaultStreamFlow-transportDefaultStreamMinRefresh { |
| 1994 | streamAdd = int32(transportDefaultStreamFlow - v) |
| 1995 | cs.inflow.add(streamAdd) |
| 1996 | } |
| 1997 | } |
| 1998 | if connAdd != 0 || streamAdd != 0 { |
| 1999 | cc.wmu.Lock() |
| 2000 | defer cc.wmu.Unlock() |
| 2001 | if connAdd != 0 { |
| 2002 | cc.fr.WriteWindowUpdate(0, mustUint31(connAdd)) |
| 2003 | } |
| 2004 | if streamAdd != 0 { |
| 2005 | cc.fr.WriteWindowUpdate(cs.ID, mustUint31(streamAdd)) |
| 2006 | } |
| 2007 | cc.bw.Flush() |
| 2008 | } |
| 2009 | return |
| 2010 | } |
| 2011 | |
| 2012 | var errClosedResponseBody = errors.New("http2: response body closed") |
| 2013 | |
| 2014 | func (b transportResponseBody) Close() error { |
| 2015 | cs := b.cs |
| 2016 | cc := cs.cc |
| 2017 | |
| 2018 | serverSentStreamEnd := cs.bufPipe.Err() == io.EOF |
| 2019 | unread := cs.bufPipe.Len() |
| 2020 | |
| 2021 | if unread > 0 || !serverSentStreamEnd { |
| 2022 | cc.mu.Lock() |
| 2023 | cc.wmu.Lock() |
| 2024 | if !serverSentStreamEnd { |
| 2025 | cc.fr.WriteRSTStream(cs.ID, ErrCodeCancel) |
| 2026 | cs.didReset = true |
| 2027 | } |
| 2028 | // Return connection-level flow control. |
| 2029 | if unread > 0 { |
| 2030 | cc.inflow.add(int32(unread)) |
| 2031 | cc.fr.WriteWindowUpdate(0, uint32(unread)) |
| 2032 | } |
| 2033 | cc.bw.Flush() |
| 2034 | cc.wmu.Unlock() |
| 2035 | cc.mu.Unlock() |
| 2036 | } |
| 2037 | |
| 2038 | cs.bufPipe.BreakWithError(errClosedResponseBody) |
| 2039 | cc.forgetStreamID(cs.ID) |
| 2040 | return nil |
| 2041 | } |
| 2042 | |
| 2043 | func (rl *clientConnReadLoop) processData(f *DataFrame) error { |
| 2044 | cc := rl.cc |
| 2045 | cs := cc.streamByID(f.StreamID, f.StreamEnded()) |
| 2046 | data := f.Data() |
| 2047 | if cs == nil { |
| 2048 | cc.mu.Lock() |
| 2049 | neverSent := cc.nextStreamID |
| 2050 | cc.mu.Unlock() |
| 2051 | if f.StreamID >= neverSent { |
| 2052 | // We never asked for this. |
| 2053 | cc.logf("http2: Transport received unsolicited DATA frame; closing connection") |
| 2054 | return ConnectionError(ErrCodeProtocol) |
| 2055 | } |
| 2056 | // We probably did ask for this, but canceled. Just ignore it. |
| 2057 | // TODO: be stricter here? only silently ignore things which |
| 2058 | // we canceled, but not things which were closed normally |
| 2059 | // by the peer? Tough without accumulating too much state. |
| 2060 | |
| 2061 | // But at least return their flow control: |
| 2062 | if f.Length > 0 { |
| 2063 | cc.mu.Lock() |
| 2064 | cc.inflow.add(int32(f.Length)) |
| 2065 | cc.mu.Unlock() |
| 2066 | |
| 2067 | cc.wmu.Lock() |
| 2068 | cc.fr.WriteWindowUpdate(0, uint32(f.Length)) |
| 2069 | cc.bw.Flush() |
| 2070 | cc.wmu.Unlock() |
| 2071 | } |
| 2072 | return nil |
| 2073 | } |
| 2074 | if !cs.firstByte { |
| 2075 | cc.logf("protocol error: received DATA before a HEADERS frame") |
| 2076 | rl.endStreamError(cs, StreamError{ |
| 2077 | StreamID: f.StreamID, |
| 2078 | Code: ErrCodeProtocol, |
| 2079 | }) |
| 2080 | return nil |
| 2081 | } |
| 2082 | if f.Length > 0 { |
| 2083 | if cs.req.Method == "HEAD" && len(data) > 0 { |
| 2084 | cc.logf("protocol error: received DATA on a HEAD request") |
| 2085 | rl.endStreamError(cs, StreamError{ |
| 2086 | StreamID: f.StreamID, |
| 2087 | Code: ErrCodeProtocol, |
| 2088 | }) |
| 2089 | return nil |
| 2090 | } |
| 2091 | // Check connection-level flow control. |
| 2092 | cc.mu.Lock() |
| 2093 | if cs.inflow.available() >= int32(f.Length) { |
| 2094 | cs.inflow.take(int32(f.Length)) |
| 2095 | } else { |
| 2096 | cc.mu.Unlock() |
| 2097 | return ConnectionError(ErrCodeFlowControl) |
| 2098 | } |
| 2099 | // Return any padded flow control now, since we won't |
| 2100 | // refund it later on body reads. |
| 2101 | var refund int |
| 2102 | if pad := int(f.Length) - len(data); pad > 0 { |
| 2103 | refund += pad |
| 2104 | } |
| 2105 | // Return len(data) now if the stream is already closed, |
| 2106 | // since data will never be read. |
| 2107 | didReset := cs.didReset |
| 2108 | if didReset { |
| 2109 | refund += len(data) |
| 2110 | } |
| 2111 | if refund > 0 { |
| 2112 | cc.inflow.add(int32(refund)) |
| 2113 | cc.wmu.Lock() |
| 2114 | cc.fr.WriteWindowUpdate(0, uint32(refund)) |
| 2115 | if !didReset { |
| 2116 | cs.inflow.add(int32(refund)) |
| 2117 | cc.fr.WriteWindowUpdate(cs.ID, uint32(refund)) |
| 2118 | } |
| 2119 | cc.bw.Flush() |
| 2120 | cc.wmu.Unlock() |
| 2121 | } |
| 2122 | cc.mu.Unlock() |
| 2123 | |
| 2124 | if len(data) > 0 && !didReset { |
| 2125 | if _, err := cs.bufPipe.Write(data); err != nil { |
| 2126 | rl.endStreamError(cs, err) |
| 2127 | return err |
| 2128 | } |
| 2129 | } |
| 2130 | } |
| 2131 | |
| 2132 | if f.StreamEnded() { |
| 2133 | rl.endStream(cs) |
| 2134 | } |
| 2135 | return nil |
| 2136 | } |
| 2137 | |
| 2138 | var errInvalidTrailers = errors.New("http2: invalid trailers") |
| 2139 | |
| 2140 | func (rl *clientConnReadLoop) endStream(cs *clientStream) { |
| 2141 | // TODO: check that any declared content-length matches, like |
| 2142 | // server.go's (*stream).endStream method. |
| 2143 | rl.endStreamError(cs, nil) |
| 2144 | } |
| 2145 | |
| 2146 | func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) { |
| 2147 | var code func() |
| 2148 | if err == nil { |
| 2149 | err = io.EOF |
| 2150 | code = cs.copyTrailers |
| 2151 | } |
| 2152 | if isConnectionCloseRequest(cs.req) { |
| 2153 | rl.closeWhenIdle = true |
| 2154 | } |
| 2155 | cs.bufPipe.closeWithErrorAndCode(err, code) |
| 2156 | |
| 2157 | select { |
| 2158 | case cs.resc <- resAndError{err: err}: |
| 2159 | default: |
| 2160 | } |
| 2161 | } |
| 2162 | |
| 2163 | func (cs *clientStream) copyTrailers() { |
| 2164 | for k, vv := range cs.trailer { |
| 2165 | t := cs.resTrailer |
| 2166 | if *t == nil { |
| 2167 | *t = make(http.Header) |
| 2168 | } |
| 2169 | (*t)[k] = vv |
| 2170 | } |
| 2171 | } |
| 2172 | |
| 2173 | func (rl *clientConnReadLoop) processGoAway(f *GoAwayFrame) error { |
| 2174 | cc := rl.cc |
| 2175 | cc.t.connPool().MarkDead(cc) |
| 2176 | if f.ErrCode != 0 { |
| 2177 | // TODO: deal with GOAWAY more. particularly the error code |
| 2178 | cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode) |
| 2179 | } |
| 2180 | cc.setGoAway(f) |
| 2181 | return nil |
| 2182 | } |
| 2183 | |
| 2184 | func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error { |
| 2185 | cc := rl.cc |
| 2186 | cc.mu.Lock() |
| 2187 | defer cc.mu.Unlock() |
| 2188 | |
| 2189 | if f.IsAck() { |
| 2190 | if cc.wantSettingsAck { |
| 2191 | cc.wantSettingsAck = false |
| 2192 | return nil |
| 2193 | } |
| 2194 | return ConnectionError(ErrCodeProtocol) |
| 2195 | } |
| 2196 | |
| 2197 | err := f.ForeachSetting(func(s Setting) error { |
| 2198 | switch s.ID { |
| 2199 | case SettingMaxFrameSize: |
| 2200 | cc.maxFrameSize = s.Val |
| 2201 | case SettingMaxConcurrentStreams: |
| 2202 | cc.maxConcurrentStreams = s.Val |
| 2203 | case SettingMaxHeaderListSize: |
| 2204 | cc.peerMaxHeaderListSize = uint64(s.Val) |
| 2205 | case SettingInitialWindowSize: |
| 2206 | // Values above the maximum flow-control |
| 2207 | // window size of 2^31-1 MUST be treated as a |
| 2208 | // connection error (Section 5.4.1) of type |
| 2209 | // FLOW_CONTROL_ERROR. |
| 2210 | if s.Val > math.MaxInt32 { |
| 2211 | return ConnectionError(ErrCodeFlowControl) |
| 2212 | } |
| 2213 | |
| 2214 | // Adjust flow control of currently-open |
| 2215 | // frames by the difference of the old initial |
| 2216 | // window size and this one. |
| 2217 | delta := int32(s.Val) - int32(cc.initialWindowSize) |
| 2218 | for _, cs := range cc.streams { |
| 2219 | cs.flow.add(delta) |
| 2220 | } |
| 2221 | cc.cond.Broadcast() |
| 2222 | |
| 2223 | cc.initialWindowSize = s.Val |
| 2224 | default: |
| 2225 | // TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably. |
| 2226 | cc.vlogf("Unhandled Setting: %v", s) |
| 2227 | } |
| 2228 | return nil |
| 2229 | }) |
| 2230 | if err != nil { |
| 2231 | return err |
| 2232 | } |
| 2233 | |
| 2234 | cc.wmu.Lock() |
| 2235 | defer cc.wmu.Unlock() |
| 2236 | |
| 2237 | cc.fr.WriteSettingsAck() |
| 2238 | cc.bw.Flush() |
| 2239 | return cc.werr |
| 2240 | } |
| 2241 | |
| 2242 | func (rl *clientConnReadLoop) processWindowUpdate(f *WindowUpdateFrame) error { |
| 2243 | cc := rl.cc |
| 2244 | cs := cc.streamByID(f.StreamID, false) |
| 2245 | if f.StreamID != 0 && cs == nil { |
| 2246 | return nil |
| 2247 | } |
| 2248 | |
| 2249 | cc.mu.Lock() |
| 2250 | defer cc.mu.Unlock() |
| 2251 | |
| 2252 | fl := &cc.flow |
| 2253 | if cs != nil { |
| 2254 | fl = &cs.flow |
| 2255 | } |
| 2256 | if !fl.add(int32(f.Increment)) { |
| 2257 | return ConnectionError(ErrCodeFlowControl) |
| 2258 | } |
| 2259 | cc.cond.Broadcast() |
| 2260 | return nil |
| 2261 | } |
| 2262 | |
| 2263 | func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error { |
| 2264 | cs := rl.cc.streamByID(f.StreamID, true) |
| 2265 | if cs == nil { |
| 2266 | // TODO: return error if server tries to RST_STEAM an idle stream |
| 2267 | return nil |
| 2268 | } |
| 2269 | select { |
| 2270 | case <-cs.peerReset: |
| 2271 | // Already reset. |
| 2272 | // This is the only goroutine |
| 2273 | // which closes this, so there |
| 2274 | // isn't a race. |
| 2275 | default: |
| 2276 | err := streamError(cs.ID, f.ErrCode) |
| 2277 | cs.resetErr = err |
| 2278 | close(cs.peerReset) |
| 2279 | cs.bufPipe.CloseWithError(err) |
| 2280 | cs.cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl |
| 2281 | } |
| 2282 | return nil |
| 2283 | } |
| 2284 | |
| 2285 | // Ping sends a PING frame to the server and waits for the ack. |
| 2286 | func (cc *ClientConn) Ping(ctx context.Context) error { |
| 2287 | c := make(chan struct{}) |
| 2288 | // Generate a random payload |
| 2289 | var p [8]byte |
| 2290 | for { |
| 2291 | if _, err := rand.Read(p[:]); err != nil { |
| 2292 | return err |
| 2293 | } |
| 2294 | cc.mu.Lock() |
| 2295 | // check for dup before insert |
| 2296 | if _, found := cc.pings[p]; !found { |
| 2297 | cc.pings[p] = c |
| 2298 | cc.mu.Unlock() |
| 2299 | break |
| 2300 | } |
| 2301 | cc.mu.Unlock() |
| 2302 | } |
| 2303 | cc.wmu.Lock() |
| 2304 | if err := cc.fr.WritePing(false, p); err != nil { |
| 2305 | cc.wmu.Unlock() |
| 2306 | return err |
| 2307 | } |
| 2308 | if err := cc.bw.Flush(); err != nil { |
| 2309 | cc.wmu.Unlock() |
| 2310 | return err |
| 2311 | } |
| 2312 | cc.wmu.Unlock() |
| 2313 | select { |
| 2314 | case <-c: |
| 2315 | return nil |
| 2316 | case <-ctx.Done(): |
| 2317 | return ctx.Err() |
| 2318 | case <-cc.readerDone: |
| 2319 | // connection closed |
| 2320 | return cc.readerErr |
| 2321 | } |
| 2322 | } |
| 2323 | |
| 2324 | func (rl *clientConnReadLoop) processPing(f *PingFrame) error { |
| 2325 | if f.IsAck() { |
| 2326 | cc := rl.cc |
| 2327 | cc.mu.Lock() |
| 2328 | defer cc.mu.Unlock() |
| 2329 | // If ack, notify listener if any |
| 2330 | if c, ok := cc.pings[f.Data]; ok { |
| 2331 | close(c) |
| 2332 | delete(cc.pings, f.Data) |
| 2333 | } |
| 2334 | return nil |
| 2335 | } |
| 2336 | cc := rl.cc |
| 2337 | cc.wmu.Lock() |
| 2338 | defer cc.wmu.Unlock() |
| 2339 | if err := cc.fr.WritePing(true, f.Data); err != nil { |
| 2340 | return err |
| 2341 | } |
| 2342 | return cc.bw.Flush() |
| 2343 | } |
| 2344 | |
| 2345 | func (rl *clientConnReadLoop) processPushPromise(f *PushPromiseFrame) error { |
| 2346 | // We told the peer we don't want them. |
| 2347 | // Spec says: |
| 2348 | // "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH |
| 2349 | // setting of the peer endpoint is set to 0. An endpoint that |
| 2350 | // has set this setting and has received acknowledgement MUST |
| 2351 | // treat the receipt of a PUSH_PROMISE frame as a connection |
| 2352 | // error (Section 5.4.1) of type PROTOCOL_ERROR." |
| 2353 | return ConnectionError(ErrCodeProtocol) |
| 2354 | } |
| 2355 | |
| 2356 | func (cc *ClientConn) writeStreamReset(streamID uint32, code ErrCode, err error) { |
| 2357 | // TODO: map err to more interesting error codes, once the |
| 2358 | // HTTP community comes up with some. But currently for |
| 2359 | // RST_STREAM there's no equivalent to GOAWAY frame's debug |
| 2360 | // data, and the error codes are all pretty vague ("cancel"). |
| 2361 | cc.wmu.Lock() |
| 2362 | cc.fr.WriteRSTStream(streamID, code) |
| 2363 | cc.bw.Flush() |
| 2364 | cc.wmu.Unlock() |
| 2365 | } |
| 2366 | |
| 2367 | var ( |
| 2368 | errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit") |
| 2369 | errRequestHeaderListSize = errors.New("http2: request header list larger than peer's advertised limit") |
| 2370 | errPseudoTrailers = errors.New("http2: invalid pseudo header in trailers") |
| 2371 | ) |
| 2372 | |
| 2373 | func (cc *ClientConn) logf(format string, args ...interface{}) { |
| 2374 | cc.t.logf(format, args...) |
| 2375 | } |
| 2376 | |
| 2377 | func (cc *ClientConn) vlogf(format string, args ...interface{}) { |
| 2378 | cc.t.vlogf(format, args...) |
| 2379 | } |
| 2380 | |
| 2381 | func (t *Transport) vlogf(format string, args ...interface{}) { |
| 2382 | if VerboseLogs { |
| 2383 | t.logf(format, args...) |
| 2384 | } |
| 2385 | } |
| 2386 | |
| 2387 | func (t *Transport) logf(format string, args ...interface{}) { |
| 2388 | log.Printf(format, args...) |
| 2389 | } |
| 2390 | |
| 2391 | var noBody io.ReadCloser = ioutil.NopCloser(bytes.NewReader(nil)) |
| 2392 | |
| 2393 | func strSliceContains(ss []string, s string) bool { |
| 2394 | for _, v := range ss { |
| 2395 | if v == s { |
| 2396 | return true |
| 2397 | } |
| 2398 | } |
| 2399 | return false |
| 2400 | } |
| 2401 | |
| 2402 | type erringRoundTripper struct{ err error } |
| 2403 | |
| 2404 | func (rt erringRoundTripper) RoundTrip(*http.Request) (*http.Response, error) { return nil, rt.err } |
| 2405 | |
| 2406 | // gzipReader wraps a response body so it can lazily |
| 2407 | // call gzip.NewReader on the first call to Read |
| 2408 | type gzipReader struct { |
| 2409 | body io.ReadCloser // underlying Response.Body |
| 2410 | zr *gzip.Reader // lazily-initialized gzip reader |
| 2411 | zerr error // sticky error |
| 2412 | } |
| 2413 | |
| 2414 | func (gz *gzipReader) Read(p []byte) (n int, err error) { |
| 2415 | if gz.zerr != nil { |
| 2416 | return 0, gz.zerr |
| 2417 | } |
| 2418 | if gz.zr == nil { |
| 2419 | gz.zr, err = gzip.NewReader(gz.body) |
| 2420 | if err != nil { |
| 2421 | gz.zerr = err |
| 2422 | return 0, err |
| 2423 | } |
| 2424 | } |
| 2425 | return gz.zr.Read(p) |
| 2426 | } |
| 2427 | |
| 2428 | func (gz *gzipReader) Close() error { |
| 2429 | return gz.body.Close() |
| 2430 | } |
| 2431 | |
| 2432 | type errorReader struct{ err error } |
| 2433 | |
| 2434 | func (r errorReader) Read(p []byte) (int, error) { return 0, r.err } |
| 2435 | |
| 2436 | // bodyWriterState encapsulates various state around the Transport's writing |
| 2437 | // of the request body, particularly regarding doing delayed writes of the body |
| 2438 | // when the request contains "Expect: 100-continue". |
| 2439 | type bodyWriterState struct { |
| 2440 | cs *clientStream |
| 2441 | timer *time.Timer // if non-nil, we're doing a delayed write |
| 2442 | fnonce *sync.Once // to call fn with |
| 2443 | fn func() // the code to run in the goroutine, writing the body |
| 2444 | resc chan error // result of fn's execution |
| 2445 | delay time.Duration // how long we should delay a delayed write for |
| 2446 | } |
| 2447 | |
| 2448 | func (t *Transport) getBodyWriterState(cs *clientStream, body io.Reader) (s bodyWriterState) { |
| 2449 | s.cs = cs |
| 2450 | if body == nil { |
| 2451 | return |
| 2452 | } |
| 2453 | resc := make(chan error, 1) |
| 2454 | s.resc = resc |
| 2455 | s.fn = func() { |
| 2456 | cs.cc.mu.Lock() |
| 2457 | cs.startedWrite = true |
| 2458 | cs.cc.mu.Unlock() |
| 2459 | resc <- cs.writeRequestBody(body, cs.req.Body) |
| 2460 | } |
| 2461 | s.delay = t.expectContinueTimeout() |
| 2462 | if s.delay == 0 || |
| 2463 | !httpguts.HeaderValuesContainsToken( |
| 2464 | cs.req.Header["Expect"], |
| 2465 | "100-continue") { |
| 2466 | return |
| 2467 | } |
| 2468 | s.fnonce = new(sync.Once) |
| 2469 | |
| 2470 | // Arm the timer with a very large duration, which we'll |
| 2471 | // intentionally lower later. It has to be large now because |
| 2472 | // we need a handle to it before writing the headers, but the |
| 2473 | // s.delay value is defined to not start until after the |
| 2474 | // request headers were written. |
| 2475 | const hugeDuration = 365 * 24 * time.Hour |
| 2476 | s.timer = time.AfterFunc(hugeDuration, func() { |
| 2477 | s.fnonce.Do(s.fn) |
| 2478 | }) |
| 2479 | return |
| 2480 | } |
| 2481 | |
| 2482 | func (s bodyWriterState) cancel() { |
| 2483 | if s.timer != nil { |
| 2484 | s.timer.Stop() |
| 2485 | } |
| 2486 | } |
| 2487 | |
| 2488 | func (s bodyWriterState) on100() { |
| 2489 | if s.timer == nil { |
| 2490 | // If we didn't do a delayed write, ignore the server's |
| 2491 | // bogus 100 continue response. |
| 2492 | return |
| 2493 | } |
| 2494 | s.timer.Stop() |
| 2495 | go func() { s.fnonce.Do(s.fn) }() |
| 2496 | } |
| 2497 | |
| 2498 | // scheduleBodyWrite starts writing the body, either immediately (in |
| 2499 | // the common case) or after the delay timeout. It should not be |
| 2500 | // called until after the headers have been written. |
| 2501 | func (s bodyWriterState) scheduleBodyWrite() { |
| 2502 | if s.timer == nil { |
| 2503 | // We're not doing a delayed write (see |
| 2504 | // getBodyWriterState), so just start the writing |
| 2505 | // goroutine immediately. |
| 2506 | go s.fn() |
| 2507 | return |
| 2508 | } |
| 2509 | traceWait100Continue(s.cs.trace) |
| 2510 | if s.timer.Stop() { |
| 2511 | s.timer.Reset(s.delay) |
| 2512 | } |
| 2513 | } |
| 2514 | |
| 2515 | // isConnectionCloseRequest reports whether req should use its own |
| 2516 | // connection for a single request and then close the connection. |
| 2517 | func isConnectionCloseRequest(req *http.Request) bool { |
| 2518 | return req.Close || httpguts.HeaderValuesContainsToken(req.Header["Connection"], "close") |
| 2519 | } |
| 2520 | |
| 2521 | // registerHTTPSProtocol calls Transport.RegisterProtocol but |
| 2522 | // converting panics into errors. |
| 2523 | func registerHTTPSProtocol(t *http.Transport, rt noDialH2RoundTripper) (err error) { |
| 2524 | defer func() { |
| 2525 | if e := recover(); e != nil { |
| 2526 | err = fmt.Errorf("%v", e) |
| 2527 | } |
| 2528 | }() |
| 2529 | t.RegisterProtocol("https", rt) |
| 2530 | return nil |
| 2531 | } |
| 2532 | |
| 2533 | // noDialH2RoundTripper is a RoundTripper which only tries to complete the request |
| 2534 | // if there's already has a cached connection to the host. |
| 2535 | // (The field is exported so it can be accessed via reflect from net/http; tested |
| 2536 | // by TestNoDialH2RoundTripperType) |
| 2537 | type noDialH2RoundTripper struct{ *Transport } |
| 2538 | |
| 2539 | func (rt noDialH2RoundTripper) RoundTrip(req *http.Request) (*http.Response, error) { |
| 2540 | res, err := rt.Transport.RoundTrip(req) |
| 2541 | if isNoCachedConnError(err) { |
| 2542 | return nil, http.ErrSkipAltProtocol |
| 2543 | } |
| 2544 | return res, err |
| 2545 | } |
| 2546 | |
| 2547 | func (t *Transport) idleConnTimeout() time.Duration { |
| 2548 | if t.t1 != nil { |
| 2549 | return t.t1.IdleConnTimeout |
| 2550 | } |
| 2551 | return 0 |
| 2552 | } |
| 2553 | |
| 2554 | func traceGetConn(req *http.Request, hostPort string) { |
| 2555 | trace := httptrace.ContextClientTrace(req.Context()) |
| 2556 | if trace == nil || trace.GetConn == nil { |
| 2557 | return |
| 2558 | } |
| 2559 | trace.GetConn(hostPort) |
| 2560 | } |
| 2561 | |
| 2562 | func traceGotConn(req *http.Request, cc *ClientConn) { |
| 2563 | trace := httptrace.ContextClientTrace(req.Context()) |
| 2564 | if trace == nil || trace.GotConn == nil { |
| 2565 | return |
| 2566 | } |
| 2567 | ci := httptrace.GotConnInfo{Conn: cc.tconn} |
| 2568 | cc.mu.Lock() |
| 2569 | ci.Reused = cc.nextStreamID > 1 |
| 2570 | ci.WasIdle = len(cc.streams) == 0 && ci.Reused |
| 2571 | if ci.WasIdle && !cc.lastActive.IsZero() { |
| 2572 | ci.IdleTime = time.Now().Sub(cc.lastActive) |
| 2573 | } |
| 2574 | cc.mu.Unlock() |
| 2575 | |
| 2576 | trace.GotConn(ci) |
| 2577 | } |
| 2578 | |
| 2579 | func traceWroteHeaders(trace *httptrace.ClientTrace) { |
| 2580 | if trace != nil && trace.WroteHeaders != nil { |
| 2581 | trace.WroteHeaders() |
| 2582 | } |
| 2583 | } |
| 2584 | |
| 2585 | func traceGot100Continue(trace *httptrace.ClientTrace) { |
| 2586 | if trace != nil && trace.Got100Continue != nil { |
| 2587 | trace.Got100Continue() |
| 2588 | } |
| 2589 | } |
| 2590 | |
| 2591 | func traceWait100Continue(trace *httptrace.ClientTrace) { |
| 2592 | if trace != nil && trace.Wait100Continue != nil { |
| 2593 | trace.Wait100Continue() |
| 2594 | } |
| 2595 | } |
| 2596 | |
| 2597 | func traceWroteRequest(trace *httptrace.ClientTrace, err error) { |
| 2598 | if trace != nil && trace.WroteRequest != nil { |
| 2599 | trace.WroteRequest(httptrace.WroteRequestInfo{Err: err}) |
| 2600 | } |
| 2601 | } |
| 2602 | |
| 2603 | func traceFirstResponseByte(trace *httptrace.ClientTrace) { |
| 2604 | if trace != nil && trace.GotFirstResponseByte != nil { |
| 2605 | trace.GotFirstResponseByte() |
| 2606 | } |
| 2607 | } |