Scott Baker | 2d89798 | 2019-09-24 11:50:08 -0700 | [diff] [blame^] | 1 | // Copyright 2014 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 | package http2 |
| 6 | |
| 7 | import ( |
| 8 | "bytes" |
| 9 | "encoding/binary" |
| 10 | "errors" |
| 11 | "fmt" |
| 12 | "io" |
| 13 | "log" |
| 14 | "strings" |
| 15 | "sync" |
| 16 | |
| 17 | "golang.org/x/net/http/httpguts" |
| 18 | "golang.org/x/net/http2/hpack" |
| 19 | ) |
| 20 | |
| 21 | const frameHeaderLen = 9 |
| 22 | |
| 23 | var padZeros = make([]byte, 255) // zeros for padding |
| 24 | |
| 25 | // A FrameType is a registered frame type as defined in |
| 26 | // http://http2.github.io/http2-spec/#rfc.section.11.2 |
| 27 | type FrameType uint8 |
| 28 | |
| 29 | const ( |
| 30 | FrameData FrameType = 0x0 |
| 31 | FrameHeaders FrameType = 0x1 |
| 32 | FramePriority FrameType = 0x2 |
| 33 | FrameRSTStream FrameType = 0x3 |
| 34 | FrameSettings FrameType = 0x4 |
| 35 | FramePushPromise FrameType = 0x5 |
| 36 | FramePing FrameType = 0x6 |
| 37 | FrameGoAway FrameType = 0x7 |
| 38 | FrameWindowUpdate FrameType = 0x8 |
| 39 | FrameContinuation FrameType = 0x9 |
| 40 | ) |
| 41 | |
| 42 | var frameName = map[FrameType]string{ |
| 43 | FrameData: "DATA", |
| 44 | FrameHeaders: "HEADERS", |
| 45 | FramePriority: "PRIORITY", |
| 46 | FrameRSTStream: "RST_STREAM", |
| 47 | FrameSettings: "SETTINGS", |
| 48 | FramePushPromise: "PUSH_PROMISE", |
| 49 | FramePing: "PING", |
| 50 | FrameGoAway: "GOAWAY", |
| 51 | FrameWindowUpdate: "WINDOW_UPDATE", |
| 52 | FrameContinuation: "CONTINUATION", |
| 53 | } |
| 54 | |
| 55 | func (t FrameType) String() string { |
| 56 | if s, ok := frameName[t]; ok { |
| 57 | return s |
| 58 | } |
| 59 | return fmt.Sprintf("UNKNOWN_FRAME_TYPE_%d", uint8(t)) |
| 60 | } |
| 61 | |
| 62 | // Flags is a bitmask of HTTP/2 flags. |
| 63 | // The meaning of flags varies depending on the frame type. |
| 64 | type Flags uint8 |
| 65 | |
| 66 | // Has reports whether f contains all (0 or more) flags in v. |
| 67 | func (f Flags) Has(v Flags) bool { |
| 68 | return (f & v) == v |
| 69 | } |
| 70 | |
| 71 | // Frame-specific FrameHeader flag bits. |
| 72 | const ( |
| 73 | // Data Frame |
| 74 | FlagDataEndStream Flags = 0x1 |
| 75 | FlagDataPadded Flags = 0x8 |
| 76 | |
| 77 | // Headers Frame |
| 78 | FlagHeadersEndStream Flags = 0x1 |
| 79 | FlagHeadersEndHeaders Flags = 0x4 |
| 80 | FlagHeadersPadded Flags = 0x8 |
| 81 | FlagHeadersPriority Flags = 0x20 |
| 82 | |
| 83 | // Settings Frame |
| 84 | FlagSettingsAck Flags = 0x1 |
| 85 | |
| 86 | // Ping Frame |
| 87 | FlagPingAck Flags = 0x1 |
| 88 | |
| 89 | // Continuation Frame |
| 90 | FlagContinuationEndHeaders Flags = 0x4 |
| 91 | |
| 92 | FlagPushPromiseEndHeaders Flags = 0x4 |
| 93 | FlagPushPromisePadded Flags = 0x8 |
| 94 | ) |
| 95 | |
| 96 | var flagName = map[FrameType]map[Flags]string{ |
| 97 | FrameData: { |
| 98 | FlagDataEndStream: "END_STREAM", |
| 99 | FlagDataPadded: "PADDED", |
| 100 | }, |
| 101 | FrameHeaders: { |
| 102 | FlagHeadersEndStream: "END_STREAM", |
| 103 | FlagHeadersEndHeaders: "END_HEADERS", |
| 104 | FlagHeadersPadded: "PADDED", |
| 105 | FlagHeadersPriority: "PRIORITY", |
| 106 | }, |
| 107 | FrameSettings: { |
| 108 | FlagSettingsAck: "ACK", |
| 109 | }, |
| 110 | FramePing: { |
| 111 | FlagPingAck: "ACK", |
| 112 | }, |
| 113 | FrameContinuation: { |
| 114 | FlagContinuationEndHeaders: "END_HEADERS", |
| 115 | }, |
| 116 | FramePushPromise: { |
| 117 | FlagPushPromiseEndHeaders: "END_HEADERS", |
| 118 | FlagPushPromisePadded: "PADDED", |
| 119 | }, |
| 120 | } |
| 121 | |
| 122 | // a frameParser parses a frame given its FrameHeader and payload |
| 123 | // bytes. The length of payload will always equal fh.Length (which |
| 124 | // might be 0). |
| 125 | type frameParser func(fc *frameCache, fh FrameHeader, payload []byte) (Frame, error) |
| 126 | |
| 127 | var frameParsers = map[FrameType]frameParser{ |
| 128 | FrameData: parseDataFrame, |
| 129 | FrameHeaders: parseHeadersFrame, |
| 130 | FramePriority: parsePriorityFrame, |
| 131 | FrameRSTStream: parseRSTStreamFrame, |
| 132 | FrameSettings: parseSettingsFrame, |
| 133 | FramePushPromise: parsePushPromise, |
| 134 | FramePing: parsePingFrame, |
| 135 | FrameGoAway: parseGoAwayFrame, |
| 136 | FrameWindowUpdate: parseWindowUpdateFrame, |
| 137 | FrameContinuation: parseContinuationFrame, |
| 138 | } |
| 139 | |
| 140 | func typeFrameParser(t FrameType) frameParser { |
| 141 | if f := frameParsers[t]; f != nil { |
| 142 | return f |
| 143 | } |
| 144 | return parseUnknownFrame |
| 145 | } |
| 146 | |
| 147 | // A FrameHeader is the 9 byte header of all HTTP/2 frames. |
| 148 | // |
| 149 | // See http://http2.github.io/http2-spec/#FrameHeader |
| 150 | type FrameHeader struct { |
| 151 | valid bool // caller can access []byte fields in the Frame |
| 152 | |
| 153 | // Type is the 1 byte frame type. There are ten standard frame |
| 154 | // types, but extension frame types may be written by WriteRawFrame |
| 155 | // and will be returned by ReadFrame (as UnknownFrame). |
| 156 | Type FrameType |
| 157 | |
| 158 | // Flags are the 1 byte of 8 potential bit flags per frame. |
| 159 | // They are specific to the frame type. |
| 160 | Flags Flags |
| 161 | |
| 162 | // Length is the length of the frame, not including the 9 byte header. |
| 163 | // The maximum size is one byte less than 16MB (uint24), but only |
| 164 | // frames up to 16KB are allowed without peer agreement. |
| 165 | Length uint32 |
| 166 | |
| 167 | // StreamID is which stream this frame is for. Certain frames |
| 168 | // are not stream-specific, in which case this field is 0. |
| 169 | StreamID uint32 |
| 170 | } |
| 171 | |
| 172 | // Header returns h. It exists so FrameHeaders can be embedded in other |
| 173 | // specific frame types and implement the Frame interface. |
| 174 | func (h FrameHeader) Header() FrameHeader { return h } |
| 175 | |
| 176 | func (h FrameHeader) String() string { |
| 177 | var buf bytes.Buffer |
| 178 | buf.WriteString("[FrameHeader ") |
| 179 | h.writeDebug(&buf) |
| 180 | buf.WriteByte(']') |
| 181 | return buf.String() |
| 182 | } |
| 183 | |
| 184 | func (h FrameHeader) writeDebug(buf *bytes.Buffer) { |
| 185 | buf.WriteString(h.Type.String()) |
| 186 | if h.Flags != 0 { |
| 187 | buf.WriteString(" flags=") |
| 188 | set := 0 |
| 189 | for i := uint8(0); i < 8; i++ { |
| 190 | if h.Flags&(1<<i) == 0 { |
| 191 | continue |
| 192 | } |
| 193 | set++ |
| 194 | if set > 1 { |
| 195 | buf.WriteByte('|') |
| 196 | } |
| 197 | name := flagName[h.Type][Flags(1<<i)] |
| 198 | if name != "" { |
| 199 | buf.WriteString(name) |
| 200 | } else { |
| 201 | fmt.Fprintf(buf, "0x%x", 1<<i) |
| 202 | } |
| 203 | } |
| 204 | } |
| 205 | if h.StreamID != 0 { |
| 206 | fmt.Fprintf(buf, " stream=%d", h.StreamID) |
| 207 | } |
| 208 | fmt.Fprintf(buf, " len=%d", h.Length) |
| 209 | } |
| 210 | |
| 211 | func (h *FrameHeader) checkValid() { |
| 212 | if !h.valid { |
| 213 | panic("Frame accessor called on non-owned Frame") |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | func (h *FrameHeader) invalidate() { h.valid = false } |
| 218 | |
| 219 | // frame header bytes. |
| 220 | // Used only by ReadFrameHeader. |
| 221 | var fhBytes = sync.Pool{ |
| 222 | New: func() interface{} { |
| 223 | buf := make([]byte, frameHeaderLen) |
| 224 | return &buf |
| 225 | }, |
| 226 | } |
| 227 | |
| 228 | // ReadFrameHeader reads 9 bytes from r and returns a FrameHeader. |
| 229 | // Most users should use Framer.ReadFrame instead. |
| 230 | func ReadFrameHeader(r io.Reader) (FrameHeader, error) { |
| 231 | bufp := fhBytes.Get().(*[]byte) |
| 232 | defer fhBytes.Put(bufp) |
| 233 | return readFrameHeader(*bufp, r) |
| 234 | } |
| 235 | |
| 236 | func readFrameHeader(buf []byte, r io.Reader) (FrameHeader, error) { |
| 237 | _, err := io.ReadFull(r, buf[:frameHeaderLen]) |
| 238 | if err != nil { |
| 239 | return FrameHeader{}, err |
| 240 | } |
| 241 | return FrameHeader{ |
| 242 | Length: (uint32(buf[0])<<16 | uint32(buf[1])<<8 | uint32(buf[2])), |
| 243 | Type: FrameType(buf[3]), |
| 244 | Flags: Flags(buf[4]), |
| 245 | StreamID: binary.BigEndian.Uint32(buf[5:]) & (1<<31 - 1), |
| 246 | valid: true, |
| 247 | }, nil |
| 248 | } |
| 249 | |
| 250 | // A Frame is the base interface implemented by all frame types. |
| 251 | // Callers will generally type-assert the specific frame type: |
| 252 | // *HeadersFrame, *SettingsFrame, *WindowUpdateFrame, etc. |
| 253 | // |
| 254 | // Frames are only valid until the next call to Framer.ReadFrame. |
| 255 | type Frame interface { |
| 256 | Header() FrameHeader |
| 257 | |
| 258 | // invalidate is called by Framer.ReadFrame to make this |
| 259 | // frame's buffers as being invalid, since the subsequent |
| 260 | // frame will reuse them. |
| 261 | invalidate() |
| 262 | } |
| 263 | |
| 264 | // A Framer reads and writes Frames. |
| 265 | type Framer struct { |
| 266 | r io.Reader |
| 267 | lastFrame Frame |
| 268 | errDetail error |
| 269 | |
| 270 | // lastHeaderStream is non-zero if the last frame was an |
| 271 | // unfinished HEADERS/CONTINUATION. |
| 272 | lastHeaderStream uint32 |
| 273 | |
| 274 | maxReadSize uint32 |
| 275 | headerBuf [frameHeaderLen]byte |
| 276 | |
| 277 | // TODO: let getReadBuf be configurable, and use a less memory-pinning |
| 278 | // allocator in server.go to minimize memory pinned for many idle conns. |
| 279 | // Will probably also need to make frame invalidation have a hook too. |
| 280 | getReadBuf func(size uint32) []byte |
| 281 | readBuf []byte // cache for default getReadBuf |
| 282 | |
| 283 | maxWriteSize uint32 // zero means unlimited; TODO: implement |
| 284 | |
| 285 | w io.Writer |
| 286 | wbuf []byte |
| 287 | |
| 288 | // AllowIllegalWrites permits the Framer's Write methods to |
| 289 | // write frames that do not conform to the HTTP/2 spec. This |
| 290 | // permits using the Framer to test other HTTP/2 |
| 291 | // implementations' conformance to the spec. |
| 292 | // If false, the Write methods will prefer to return an error |
| 293 | // rather than comply. |
| 294 | AllowIllegalWrites bool |
| 295 | |
| 296 | // AllowIllegalReads permits the Framer's ReadFrame method |
| 297 | // to return non-compliant frames or frame orders. |
| 298 | // This is for testing and permits using the Framer to test |
| 299 | // other HTTP/2 implementations' conformance to the spec. |
| 300 | // It is not compatible with ReadMetaHeaders. |
| 301 | AllowIllegalReads bool |
| 302 | |
| 303 | // ReadMetaHeaders if non-nil causes ReadFrame to merge |
| 304 | // HEADERS and CONTINUATION frames together and return |
| 305 | // MetaHeadersFrame instead. |
| 306 | ReadMetaHeaders *hpack.Decoder |
| 307 | |
| 308 | // MaxHeaderListSize is the http2 MAX_HEADER_LIST_SIZE. |
| 309 | // It's used only if ReadMetaHeaders is set; 0 means a sane default |
| 310 | // (currently 16MB) |
| 311 | // If the limit is hit, MetaHeadersFrame.Truncated is set true. |
| 312 | MaxHeaderListSize uint32 |
| 313 | |
| 314 | // TODO: track which type of frame & with which flags was sent |
| 315 | // last. Then return an error (unless AllowIllegalWrites) if |
| 316 | // we're in the middle of a header block and a |
| 317 | // non-Continuation or Continuation on a different stream is |
| 318 | // attempted to be written. |
| 319 | |
| 320 | logReads, logWrites bool |
| 321 | |
| 322 | debugFramer *Framer // only use for logging written writes |
| 323 | debugFramerBuf *bytes.Buffer |
| 324 | debugReadLoggerf func(string, ...interface{}) |
| 325 | debugWriteLoggerf func(string, ...interface{}) |
| 326 | |
| 327 | frameCache *frameCache // nil if frames aren't reused (default) |
| 328 | } |
| 329 | |
| 330 | func (fr *Framer) maxHeaderListSize() uint32 { |
| 331 | if fr.MaxHeaderListSize == 0 { |
| 332 | return 16 << 20 // sane default, per docs |
| 333 | } |
| 334 | return fr.MaxHeaderListSize |
| 335 | } |
| 336 | |
| 337 | func (f *Framer) startWrite(ftype FrameType, flags Flags, streamID uint32) { |
| 338 | // Write the FrameHeader. |
| 339 | f.wbuf = append(f.wbuf[:0], |
| 340 | 0, // 3 bytes of length, filled in in endWrite |
| 341 | 0, |
| 342 | 0, |
| 343 | byte(ftype), |
| 344 | byte(flags), |
| 345 | byte(streamID>>24), |
| 346 | byte(streamID>>16), |
| 347 | byte(streamID>>8), |
| 348 | byte(streamID)) |
| 349 | } |
| 350 | |
| 351 | func (f *Framer) endWrite() error { |
| 352 | // Now that we know the final size, fill in the FrameHeader in |
| 353 | // the space previously reserved for it. Abuse append. |
| 354 | length := len(f.wbuf) - frameHeaderLen |
| 355 | if length >= (1 << 24) { |
| 356 | return ErrFrameTooLarge |
| 357 | } |
| 358 | _ = append(f.wbuf[:0], |
| 359 | byte(length>>16), |
| 360 | byte(length>>8), |
| 361 | byte(length)) |
| 362 | if f.logWrites { |
| 363 | f.logWrite() |
| 364 | } |
| 365 | |
| 366 | n, err := f.w.Write(f.wbuf) |
| 367 | if err == nil && n != len(f.wbuf) { |
| 368 | err = io.ErrShortWrite |
| 369 | } |
| 370 | return err |
| 371 | } |
| 372 | |
| 373 | func (f *Framer) logWrite() { |
| 374 | if f.debugFramer == nil { |
| 375 | f.debugFramerBuf = new(bytes.Buffer) |
| 376 | f.debugFramer = NewFramer(nil, f.debugFramerBuf) |
| 377 | f.debugFramer.logReads = false // we log it ourselves, saying "wrote" below |
| 378 | // Let us read anything, even if we accidentally wrote it |
| 379 | // in the wrong order: |
| 380 | f.debugFramer.AllowIllegalReads = true |
| 381 | } |
| 382 | f.debugFramerBuf.Write(f.wbuf) |
| 383 | fr, err := f.debugFramer.ReadFrame() |
| 384 | if err != nil { |
| 385 | f.debugWriteLoggerf("http2: Framer %p: failed to decode just-written frame", f) |
| 386 | return |
| 387 | } |
| 388 | f.debugWriteLoggerf("http2: Framer %p: wrote %v", f, summarizeFrame(fr)) |
| 389 | } |
| 390 | |
| 391 | func (f *Framer) writeByte(v byte) { f.wbuf = append(f.wbuf, v) } |
| 392 | func (f *Framer) writeBytes(v []byte) { f.wbuf = append(f.wbuf, v...) } |
| 393 | func (f *Framer) writeUint16(v uint16) { f.wbuf = append(f.wbuf, byte(v>>8), byte(v)) } |
| 394 | func (f *Framer) writeUint32(v uint32) { |
| 395 | f.wbuf = append(f.wbuf, byte(v>>24), byte(v>>16), byte(v>>8), byte(v)) |
| 396 | } |
| 397 | |
| 398 | const ( |
| 399 | minMaxFrameSize = 1 << 14 |
| 400 | maxFrameSize = 1<<24 - 1 |
| 401 | ) |
| 402 | |
| 403 | // SetReuseFrames allows the Framer to reuse Frames. |
| 404 | // If called on a Framer, Frames returned by calls to ReadFrame are only |
| 405 | // valid until the next call to ReadFrame. |
| 406 | func (fr *Framer) SetReuseFrames() { |
| 407 | if fr.frameCache != nil { |
| 408 | return |
| 409 | } |
| 410 | fr.frameCache = &frameCache{} |
| 411 | } |
| 412 | |
| 413 | type frameCache struct { |
| 414 | dataFrame DataFrame |
| 415 | } |
| 416 | |
| 417 | func (fc *frameCache) getDataFrame() *DataFrame { |
| 418 | if fc == nil { |
| 419 | return &DataFrame{} |
| 420 | } |
| 421 | return &fc.dataFrame |
| 422 | } |
| 423 | |
| 424 | // NewFramer returns a Framer that writes frames to w and reads them from r. |
| 425 | func NewFramer(w io.Writer, r io.Reader) *Framer { |
| 426 | fr := &Framer{ |
| 427 | w: w, |
| 428 | r: r, |
| 429 | logReads: logFrameReads, |
| 430 | logWrites: logFrameWrites, |
| 431 | debugReadLoggerf: log.Printf, |
| 432 | debugWriteLoggerf: log.Printf, |
| 433 | } |
| 434 | fr.getReadBuf = func(size uint32) []byte { |
| 435 | if cap(fr.readBuf) >= int(size) { |
| 436 | return fr.readBuf[:size] |
| 437 | } |
| 438 | fr.readBuf = make([]byte, size) |
| 439 | return fr.readBuf |
| 440 | } |
| 441 | fr.SetMaxReadFrameSize(maxFrameSize) |
| 442 | return fr |
| 443 | } |
| 444 | |
| 445 | // SetMaxReadFrameSize sets the maximum size of a frame |
| 446 | // that will be read by a subsequent call to ReadFrame. |
| 447 | // It is the caller's responsibility to advertise this |
| 448 | // limit with a SETTINGS frame. |
| 449 | func (fr *Framer) SetMaxReadFrameSize(v uint32) { |
| 450 | if v > maxFrameSize { |
| 451 | v = maxFrameSize |
| 452 | } |
| 453 | fr.maxReadSize = v |
| 454 | } |
| 455 | |
| 456 | // ErrorDetail returns a more detailed error of the last error |
| 457 | // returned by Framer.ReadFrame. For instance, if ReadFrame |
| 458 | // returns a StreamError with code PROTOCOL_ERROR, ErrorDetail |
| 459 | // will say exactly what was invalid. ErrorDetail is not guaranteed |
| 460 | // to return a non-nil value and like the rest of the http2 package, |
| 461 | // its return value is not protected by an API compatibility promise. |
| 462 | // ErrorDetail is reset after the next call to ReadFrame. |
| 463 | func (fr *Framer) ErrorDetail() error { |
| 464 | return fr.errDetail |
| 465 | } |
| 466 | |
| 467 | // ErrFrameTooLarge is returned from Framer.ReadFrame when the peer |
| 468 | // sends a frame that is larger than declared with SetMaxReadFrameSize. |
| 469 | var ErrFrameTooLarge = errors.New("http2: frame too large") |
| 470 | |
| 471 | // terminalReadFrameError reports whether err is an unrecoverable |
| 472 | // error from ReadFrame and no other frames should be read. |
| 473 | func terminalReadFrameError(err error) bool { |
| 474 | if _, ok := err.(StreamError); ok { |
| 475 | return false |
| 476 | } |
| 477 | return err != nil |
| 478 | } |
| 479 | |
| 480 | // ReadFrame reads a single frame. The returned Frame is only valid |
| 481 | // until the next call to ReadFrame. |
| 482 | // |
| 483 | // If the frame is larger than previously set with SetMaxReadFrameSize, the |
| 484 | // returned error is ErrFrameTooLarge. Other errors may be of type |
| 485 | // ConnectionError, StreamError, or anything else from the underlying |
| 486 | // reader. |
| 487 | func (fr *Framer) ReadFrame() (Frame, error) { |
| 488 | fr.errDetail = nil |
| 489 | if fr.lastFrame != nil { |
| 490 | fr.lastFrame.invalidate() |
| 491 | } |
| 492 | fh, err := readFrameHeader(fr.headerBuf[:], fr.r) |
| 493 | if err != nil { |
| 494 | return nil, err |
| 495 | } |
| 496 | if fh.Length > fr.maxReadSize { |
| 497 | return nil, ErrFrameTooLarge |
| 498 | } |
| 499 | payload := fr.getReadBuf(fh.Length) |
| 500 | if _, err := io.ReadFull(fr.r, payload); err != nil { |
| 501 | return nil, err |
| 502 | } |
| 503 | f, err := typeFrameParser(fh.Type)(fr.frameCache, fh, payload) |
| 504 | if err != nil { |
| 505 | if ce, ok := err.(connError); ok { |
| 506 | return nil, fr.connError(ce.Code, ce.Reason) |
| 507 | } |
| 508 | return nil, err |
| 509 | } |
| 510 | if err := fr.checkFrameOrder(f); err != nil { |
| 511 | return nil, err |
| 512 | } |
| 513 | if fr.logReads { |
| 514 | fr.debugReadLoggerf("http2: Framer %p: read %v", fr, summarizeFrame(f)) |
| 515 | } |
| 516 | if fh.Type == FrameHeaders && fr.ReadMetaHeaders != nil { |
| 517 | return fr.readMetaFrame(f.(*HeadersFrame)) |
| 518 | } |
| 519 | return f, nil |
| 520 | } |
| 521 | |
| 522 | // connError returns ConnectionError(code) but first |
| 523 | // stashes away a public reason to the caller can optionally relay it |
| 524 | // to the peer before hanging up on them. This might help others debug |
| 525 | // their implementations. |
| 526 | func (fr *Framer) connError(code ErrCode, reason string) error { |
| 527 | fr.errDetail = errors.New(reason) |
| 528 | return ConnectionError(code) |
| 529 | } |
| 530 | |
| 531 | // checkFrameOrder reports an error if f is an invalid frame to return |
| 532 | // next from ReadFrame. Mostly it checks whether HEADERS and |
| 533 | // CONTINUATION frames are contiguous. |
| 534 | func (fr *Framer) checkFrameOrder(f Frame) error { |
| 535 | last := fr.lastFrame |
| 536 | fr.lastFrame = f |
| 537 | if fr.AllowIllegalReads { |
| 538 | return nil |
| 539 | } |
| 540 | |
| 541 | fh := f.Header() |
| 542 | if fr.lastHeaderStream != 0 { |
| 543 | if fh.Type != FrameContinuation { |
| 544 | return fr.connError(ErrCodeProtocol, |
| 545 | fmt.Sprintf("got %s for stream %d; expected CONTINUATION following %s for stream %d", |
| 546 | fh.Type, fh.StreamID, |
| 547 | last.Header().Type, fr.lastHeaderStream)) |
| 548 | } |
| 549 | if fh.StreamID != fr.lastHeaderStream { |
| 550 | return fr.connError(ErrCodeProtocol, |
| 551 | fmt.Sprintf("got CONTINUATION for stream %d; expected stream %d", |
| 552 | fh.StreamID, fr.lastHeaderStream)) |
| 553 | } |
| 554 | } else if fh.Type == FrameContinuation { |
| 555 | return fr.connError(ErrCodeProtocol, fmt.Sprintf("unexpected CONTINUATION for stream %d", fh.StreamID)) |
| 556 | } |
| 557 | |
| 558 | switch fh.Type { |
| 559 | case FrameHeaders, FrameContinuation: |
| 560 | if fh.Flags.Has(FlagHeadersEndHeaders) { |
| 561 | fr.lastHeaderStream = 0 |
| 562 | } else { |
| 563 | fr.lastHeaderStream = fh.StreamID |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | return nil |
| 568 | } |
| 569 | |
| 570 | // A DataFrame conveys arbitrary, variable-length sequences of octets |
| 571 | // associated with a stream. |
| 572 | // See http://http2.github.io/http2-spec/#rfc.section.6.1 |
| 573 | type DataFrame struct { |
| 574 | FrameHeader |
| 575 | data []byte |
| 576 | } |
| 577 | |
| 578 | func (f *DataFrame) StreamEnded() bool { |
| 579 | return f.FrameHeader.Flags.Has(FlagDataEndStream) |
| 580 | } |
| 581 | |
| 582 | // Data returns the frame's data octets, not including any padding |
| 583 | // size byte or padding suffix bytes. |
| 584 | // The caller must not retain the returned memory past the next |
| 585 | // call to ReadFrame. |
| 586 | func (f *DataFrame) Data() []byte { |
| 587 | f.checkValid() |
| 588 | return f.data |
| 589 | } |
| 590 | |
| 591 | func parseDataFrame(fc *frameCache, fh FrameHeader, payload []byte) (Frame, error) { |
| 592 | if fh.StreamID == 0 { |
| 593 | // DATA frames MUST be associated with a stream. If a |
| 594 | // DATA frame is received whose stream identifier |
| 595 | // field is 0x0, the recipient MUST respond with a |
| 596 | // connection error (Section 5.4.1) of type |
| 597 | // PROTOCOL_ERROR. |
| 598 | return nil, connError{ErrCodeProtocol, "DATA frame with stream ID 0"} |
| 599 | } |
| 600 | f := fc.getDataFrame() |
| 601 | f.FrameHeader = fh |
| 602 | |
| 603 | var padSize byte |
| 604 | if fh.Flags.Has(FlagDataPadded) { |
| 605 | var err error |
| 606 | payload, padSize, err = readByte(payload) |
| 607 | if err != nil { |
| 608 | return nil, err |
| 609 | } |
| 610 | } |
| 611 | if int(padSize) > len(payload) { |
| 612 | // If the length of the padding is greater than the |
| 613 | // length of the frame payload, the recipient MUST |
| 614 | // treat this as a connection error. |
| 615 | // Filed: https://github.com/http2/http2-spec/issues/610 |
| 616 | return nil, connError{ErrCodeProtocol, "pad size larger than data payload"} |
| 617 | } |
| 618 | f.data = payload[:len(payload)-int(padSize)] |
| 619 | return f, nil |
| 620 | } |
| 621 | |
| 622 | var ( |
| 623 | errStreamID = errors.New("invalid stream ID") |
| 624 | errDepStreamID = errors.New("invalid dependent stream ID") |
| 625 | errPadLength = errors.New("pad length too large") |
| 626 | errPadBytes = errors.New("padding bytes must all be zeros unless AllowIllegalWrites is enabled") |
| 627 | ) |
| 628 | |
| 629 | func validStreamIDOrZero(streamID uint32) bool { |
| 630 | return streamID&(1<<31) == 0 |
| 631 | } |
| 632 | |
| 633 | func validStreamID(streamID uint32) bool { |
| 634 | return streamID != 0 && streamID&(1<<31) == 0 |
| 635 | } |
| 636 | |
| 637 | // WriteData writes a DATA frame. |
| 638 | // |
| 639 | // It will perform exactly one Write to the underlying Writer. |
| 640 | // It is the caller's responsibility not to violate the maximum frame size |
| 641 | // and to not call other Write methods concurrently. |
| 642 | func (f *Framer) WriteData(streamID uint32, endStream bool, data []byte) error { |
| 643 | return f.WriteDataPadded(streamID, endStream, data, nil) |
| 644 | } |
| 645 | |
| 646 | // WriteDataPadded writes a DATA frame with optional padding. |
| 647 | // |
| 648 | // If pad is nil, the padding bit is not sent. |
| 649 | // The length of pad must not exceed 255 bytes. |
| 650 | // The bytes of pad must all be zero, unless f.AllowIllegalWrites is set. |
| 651 | // |
| 652 | // It will perform exactly one Write to the underlying Writer. |
| 653 | // It is the caller's responsibility not to violate the maximum frame size |
| 654 | // and to not call other Write methods concurrently. |
| 655 | func (f *Framer) WriteDataPadded(streamID uint32, endStream bool, data, pad []byte) error { |
| 656 | if !validStreamID(streamID) && !f.AllowIllegalWrites { |
| 657 | return errStreamID |
| 658 | } |
| 659 | if len(pad) > 0 { |
| 660 | if len(pad) > 255 { |
| 661 | return errPadLength |
| 662 | } |
| 663 | if !f.AllowIllegalWrites { |
| 664 | for _, b := range pad { |
| 665 | if b != 0 { |
| 666 | // "Padding octets MUST be set to zero when sending." |
| 667 | return errPadBytes |
| 668 | } |
| 669 | } |
| 670 | } |
| 671 | } |
| 672 | var flags Flags |
| 673 | if endStream { |
| 674 | flags |= FlagDataEndStream |
| 675 | } |
| 676 | if pad != nil { |
| 677 | flags |= FlagDataPadded |
| 678 | } |
| 679 | f.startWrite(FrameData, flags, streamID) |
| 680 | if pad != nil { |
| 681 | f.wbuf = append(f.wbuf, byte(len(pad))) |
| 682 | } |
| 683 | f.wbuf = append(f.wbuf, data...) |
| 684 | f.wbuf = append(f.wbuf, pad...) |
| 685 | return f.endWrite() |
| 686 | } |
| 687 | |
| 688 | // A SettingsFrame conveys configuration parameters that affect how |
| 689 | // endpoints communicate, such as preferences and constraints on peer |
| 690 | // behavior. |
| 691 | // |
| 692 | // See http://http2.github.io/http2-spec/#SETTINGS |
| 693 | type SettingsFrame struct { |
| 694 | FrameHeader |
| 695 | p []byte |
| 696 | } |
| 697 | |
| 698 | func parseSettingsFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 699 | if fh.Flags.Has(FlagSettingsAck) && fh.Length > 0 { |
| 700 | // When this (ACK 0x1) bit is set, the payload of the |
| 701 | // SETTINGS frame MUST be empty. Receipt of a |
| 702 | // SETTINGS frame with the ACK flag set and a length |
| 703 | // field value other than 0 MUST be treated as a |
| 704 | // connection error (Section 5.4.1) of type |
| 705 | // FRAME_SIZE_ERROR. |
| 706 | return nil, ConnectionError(ErrCodeFrameSize) |
| 707 | } |
| 708 | if fh.StreamID != 0 { |
| 709 | // SETTINGS frames always apply to a connection, |
| 710 | // never a single stream. The stream identifier for a |
| 711 | // SETTINGS frame MUST be zero (0x0). If an endpoint |
| 712 | // receives a SETTINGS frame whose stream identifier |
| 713 | // field is anything other than 0x0, the endpoint MUST |
| 714 | // respond with a connection error (Section 5.4.1) of |
| 715 | // type PROTOCOL_ERROR. |
| 716 | return nil, ConnectionError(ErrCodeProtocol) |
| 717 | } |
| 718 | if len(p)%6 != 0 { |
| 719 | // Expecting even number of 6 byte settings. |
| 720 | return nil, ConnectionError(ErrCodeFrameSize) |
| 721 | } |
| 722 | f := &SettingsFrame{FrameHeader: fh, p: p} |
| 723 | if v, ok := f.Value(SettingInitialWindowSize); ok && v > (1<<31)-1 { |
| 724 | // Values above the maximum flow control window size of 2^31 - 1 MUST |
| 725 | // be treated as a connection error (Section 5.4.1) of type |
| 726 | // FLOW_CONTROL_ERROR. |
| 727 | return nil, ConnectionError(ErrCodeFlowControl) |
| 728 | } |
| 729 | return f, nil |
| 730 | } |
| 731 | |
| 732 | func (f *SettingsFrame) IsAck() bool { |
| 733 | return f.FrameHeader.Flags.Has(FlagSettingsAck) |
| 734 | } |
| 735 | |
| 736 | func (f *SettingsFrame) Value(id SettingID) (v uint32, ok bool) { |
| 737 | f.checkValid() |
| 738 | for i := 0; i < f.NumSettings(); i++ { |
| 739 | if s := f.Setting(i); s.ID == id { |
| 740 | return s.Val, true |
| 741 | } |
| 742 | } |
| 743 | return 0, false |
| 744 | } |
| 745 | |
| 746 | // Setting returns the setting from the frame at the given 0-based index. |
| 747 | // The index must be >= 0 and less than f.NumSettings(). |
| 748 | func (f *SettingsFrame) Setting(i int) Setting { |
| 749 | buf := f.p |
| 750 | return Setting{ |
| 751 | ID: SettingID(binary.BigEndian.Uint16(buf[i*6 : i*6+2])), |
| 752 | Val: binary.BigEndian.Uint32(buf[i*6+2 : i*6+6]), |
| 753 | } |
| 754 | } |
| 755 | |
| 756 | func (f *SettingsFrame) NumSettings() int { return len(f.p) / 6 } |
| 757 | |
| 758 | // HasDuplicates reports whether f contains any duplicate setting IDs. |
| 759 | func (f *SettingsFrame) HasDuplicates() bool { |
| 760 | num := f.NumSettings() |
| 761 | if num == 0 { |
| 762 | return false |
| 763 | } |
| 764 | // If it's small enough (the common case), just do the n^2 |
| 765 | // thing and avoid a map allocation. |
| 766 | if num < 10 { |
| 767 | for i := 0; i < num; i++ { |
| 768 | idi := f.Setting(i).ID |
| 769 | for j := i + 1; j < num; j++ { |
| 770 | idj := f.Setting(j).ID |
| 771 | if idi == idj { |
| 772 | return true |
| 773 | } |
| 774 | } |
| 775 | } |
| 776 | return false |
| 777 | } |
| 778 | seen := map[SettingID]bool{} |
| 779 | for i := 0; i < num; i++ { |
| 780 | id := f.Setting(i).ID |
| 781 | if seen[id] { |
| 782 | return true |
| 783 | } |
| 784 | seen[id] = true |
| 785 | } |
| 786 | return false |
| 787 | } |
| 788 | |
| 789 | // ForeachSetting runs fn for each setting. |
| 790 | // It stops and returns the first error. |
| 791 | func (f *SettingsFrame) ForeachSetting(fn func(Setting) error) error { |
| 792 | f.checkValid() |
| 793 | for i := 0; i < f.NumSettings(); i++ { |
| 794 | if err := fn(f.Setting(i)); err != nil { |
| 795 | return err |
| 796 | } |
| 797 | } |
| 798 | return nil |
| 799 | } |
| 800 | |
| 801 | // WriteSettings writes a SETTINGS frame with zero or more settings |
| 802 | // specified and the ACK bit not set. |
| 803 | // |
| 804 | // It will perform exactly one Write to the underlying Writer. |
| 805 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 806 | func (f *Framer) WriteSettings(settings ...Setting) error { |
| 807 | f.startWrite(FrameSettings, 0, 0) |
| 808 | for _, s := range settings { |
| 809 | f.writeUint16(uint16(s.ID)) |
| 810 | f.writeUint32(s.Val) |
| 811 | } |
| 812 | return f.endWrite() |
| 813 | } |
| 814 | |
| 815 | // WriteSettingsAck writes an empty SETTINGS frame with the ACK bit set. |
| 816 | // |
| 817 | // It will perform exactly one Write to the underlying Writer. |
| 818 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 819 | func (f *Framer) WriteSettingsAck() error { |
| 820 | f.startWrite(FrameSettings, FlagSettingsAck, 0) |
| 821 | return f.endWrite() |
| 822 | } |
| 823 | |
| 824 | // A PingFrame is a mechanism for measuring a minimal round trip time |
| 825 | // from the sender, as well as determining whether an idle connection |
| 826 | // is still functional. |
| 827 | // See http://http2.github.io/http2-spec/#rfc.section.6.7 |
| 828 | type PingFrame struct { |
| 829 | FrameHeader |
| 830 | Data [8]byte |
| 831 | } |
| 832 | |
| 833 | func (f *PingFrame) IsAck() bool { return f.Flags.Has(FlagPingAck) } |
| 834 | |
| 835 | func parsePingFrame(_ *frameCache, fh FrameHeader, payload []byte) (Frame, error) { |
| 836 | if len(payload) != 8 { |
| 837 | return nil, ConnectionError(ErrCodeFrameSize) |
| 838 | } |
| 839 | if fh.StreamID != 0 { |
| 840 | return nil, ConnectionError(ErrCodeProtocol) |
| 841 | } |
| 842 | f := &PingFrame{FrameHeader: fh} |
| 843 | copy(f.Data[:], payload) |
| 844 | return f, nil |
| 845 | } |
| 846 | |
| 847 | func (f *Framer) WritePing(ack bool, data [8]byte) error { |
| 848 | var flags Flags |
| 849 | if ack { |
| 850 | flags = FlagPingAck |
| 851 | } |
| 852 | f.startWrite(FramePing, flags, 0) |
| 853 | f.writeBytes(data[:]) |
| 854 | return f.endWrite() |
| 855 | } |
| 856 | |
| 857 | // A GoAwayFrame informs the remote peer to stop creating streams on this connection. |
| 858 | // See http://http2.github.io/http2-spec/#rfc.section.6.8 |
| 859 | type GoAwayFrame struct { |
| 860 | FrameHeader |
| 861 | LastStreamID uint32 |
| 862 | ErrCode ErrCode |
| 863 | debugData []byte |
| 864 | } |
| 865 | |
| 866 | // DebugData returns any debug data in the GOAWAY frame. Its contents |
| 867 | // are not defined. |
| 868 | // The caller must not retain the returned memory past the next |
| 869 | // call to ReadFrame. |
| 870 | func (f *GoAwayFrame) DebugData() []byte { |
| 871 | f.checkValid() |
| 872 | return f.debugData |
| 873 | } |
| 874 | |
| 875 | func parseGoAwayFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 876 | if fh.StreamID != 0 { |
| 877 | return nil, ConnectionError(ErrCodeProtocol) |
| 878 | } |
| 879 | if len(p) < 8 { |
| 880 | return nil, ConnectionError(ErrCodeFrameSize) |
| 881 | } |
| 882 | return &GoAwayFrame{ |
| 883 | FrameHeader: fh, |
| 884 | LastStreamID: binary.BigEndian.Uint32(p[:4]) & (1<<31 - 1), |
| 885 | ErrCode: ErrCode(binary.BigEndian.Uint32(p[4:8])), |
| 886 | debugData: p[8:], |
| 887 | }, nil |
| 888 | } |
| 889 | |
| 890 | func (f *Framer) WriteGoAway(maxStreamID uint32, code ErrCode, debugData []byte) error { |
| 891 | f.startWrite(FrameGoAway, 0, 0) |
| 892 | f.writeUint32(maxStreamID & (1<<31 - 1)) |
| 893 | f.writeUint32(uint32(code)) |
| 894 | f.writeBytes(debugData) |
| 895 | return f.endWrite() |
| 896 | } |
| 897 | |
| 898 | // An UnknownFrame is the frame type returned when the frame type is unknown |
| 899 | // or no specific frame type parser exists. |
| 900 | type UnknownFrame struct { |
| 901 | FrameHeader |
| 902 | p []byte |
| 903 | } |
| 904 | |
| 905 | // Payload returns the frame's payload (after the header). It is not |
| 906 | // valid to call this method after a subsequent call to |
| 907 | // Framer.ReadFrame, nor is it valid to retain the returned slice. |
| 908 | // The memory is owned by the Framer and is invalidated when the next |
| 909 | // frame is read. |
| 910 | func (f *UnknownFrame) Payload() []byte { |
| 911 | f.checkValid() |
| 912 | return f.p |
| 913 | } |
| 914 | |
| 915 | func parseUnknownFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 916 | return &UnknownFrame{fh, p}, nil |
| 917 | } |
| 918 | |
| 919 | // A WindowUpdateFrame is used to implement flow control. |
| 920 | // See http://http2.github.io/http2-spec/#rfc.section.6.9 |
| 921 | type WindowUpdateFrame struct { |
| 922 | FrameHeader |
| 923 | Increment uint32 // never read with high bit set |
| 924 | } |
| 925 | |
| 926 | func parseWindowUpdateFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 927 | if len(p) != 4 { |
| 928 | return nil, ConnectionError(ErrCodeFrameSize) |
| 929 | } |
| 930 | inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff // mask off high reserved bit |
| 931 | if inc == 0 { |
| 932 | // A receiver MUST treat the receipt of a |
| 933 | // WINDOW_UPDATE frame with an flow control window |
| 934 | // increment of 0 as a stream error (Section 5.4.2) of |
| 935 | // type PROTOCOL_ERROR; errors on the connection flow |
| 936 | // control window MUST be treated as a connection |
| 937 | // error (Section 5.4.1). |
| 938 | if fh.StreamID == 0 { |
| 939 | return nil, ConnectionError(ErrCodeProtocol) |
| 940 | } |
| 941 | return nil, streamError(fh.StreamID, ErrCodeProtocol) |
| 942 | } |
| 943 | return &WindowUpdateFrame{ |
| 944 | FrameHeader: fh, |
| 945 | Increment: inc, |
| 946 | }, nil |
| 947 | } |
| 948 | |
| 949 | // WriteWindowUpdate writes a WINDOW_UPDATE frame. |
| 950 | // The increment value must be between 1 and 2,147,483,647, inclusive. |
| 951 | // If the Stream ID is zero, the window update applies to the |
| 952 | // connection as a whole. |
| 953 | func (f *Framer) WriteWindowUpdate(streamID, incr uint32) error { |
| 954 | // "The legal range for the increment to the flow control window is 1 to 2^31-1 (2,147,483,647) octets." |
| 955 | if (incr < 1 || incr > 2147483647) && !f.AllowIllegalWrites { |
| 956 | return errors.New("illegal window increment value") |
| 957 | } |
| 958 | f.startWrite(FrameWindowUpdate, 0, streamID) |
| 959 | f.writeUint32(incr) |
| 960 | return f.endWrite() |
| 961 | } |
| 962 | |
| 963 | // A HeadersFrame is used to open a stream and additionally carries a |
| 964 | // header block fragment. |
| 965 | type HeadersFrame struct { |
| 966 | FrameHeader |
| 967 | |
| 968 | // Priority is set if FlagHeadersPriority is set in the FrameHeader. |
| 969 | Priority PriorityParam |
| 970 | |
| 971 | headerFragBuf []byte // not owned |
| 972 | } |
| 973 | |
| 974 | func (f *HeadersFrame) HeaderBlockFragment() []byte { |
| 975 | f.checkValid() |
| 976 | return f.headerFragBuf |
| 977 | } |
| 978 | |
| 979 | func (f *HeadersFrame) HeadersEnded() bool { |
| 980 | return f.FrameHeader.Flags.Has(FlagHeadersEndHeaders) |
| 981 | } |
| 982 | |
| 983 | func (f *HeadersFrame) StreamEnded() bool { |
| 984 | return f.FrameHeader.Flags.Has(FlagHeadersEndStream) |
| 985 | } |
| 986 | |
| 987 | func (f *HeadersFrame) HasPriority() bool { |
| 988 | return f.FrameHeader.Flags.Has(FlagHeadersPriority) |
| 989 | } |
| 990 | |
| 991 | func parseHeadersFrame(_ *frameCache, fh FrameHeader, p []byte) (_ Frame, err error) { |
| 992 | hf := &HeadersFrame{ |
| 993 | FrameHeader: fh, |
| 994 | } |
| 995 | if fh.StreamID == 0 { |
| 996 | // HEADERS frames MUST be associated with a stream. If a HEADERS frame |
| 997 | // is received whose stream identifier field is 0x0, the recipient MUST |
| 998 | // respond with a connection error (Section 5.4.1) of type |
| 999 | // PROTOCOL_ERROR. |
| 1000 | return nil, connError{ErrCodeProtocol, "HEADERS frame with stream ID 0"} |
| 1001 | } |
| 1002 | var padLength uint8 |
| 1003 | if fh.Flags.Has(FlagHeadersPadded) { |
| 1004 | if p, padLength, err = readByte(p); err != nil { |
| 1005 | return |
| 1006 | } |
| 1007 | } |
| 1008 | if fh.Flags.Has(FlagHeadersPriority) { |
| 1009 | var v uint32 |
| 1010 | p, v, err = readUint32(p) |
| 1011 | if err != nil { |
| 1012 | return nil, err |
| 1013 | } |
| 1014 | hf.Priority.StreamDep = v & 0x7fffffff |
| 1015 | hf.Priority.Exclusive = (v != hf.Priority.StreamDep) // high bit was set |
| 1016 | p, hf.Priority.Weight, err = readByte(p) |
| 1017 | if err != nil { |
| 1018 | return nil, err |
| 1019 | } |
| 1020 | } |
| 1021 | if len(p)-int(padLength) <= 0 { |
| 1022 | return nil, streamError(fh.StreamID, ErrCodeProtocol) |
| 1023 | } |
| 1024 | hf.headerFragBuf = p[:len(p)-int(padLength)] |
| 1025 | return hf, nil |
| 1026 | } |
| 1027 | |
| 1028 | // HeadersFrameParam are the parameters for writing a HEADERS frame. |
| 1029 | type HeadersFrameParam struct { |
| 1030 | // StreamID is the required Stream ID to initiate. |
| 1031 | StreamID uint32 |
| 1032 | // BlockFragment is part (or all) of a Header Block. |
| 1033 | BlockFragment []byte |
| 1034 | |
| 1035 | // EndStream indicates that the header block is the last that |
| 1036 | // the endpoint will send for the identified stream. Setting |
| 1037 | // this flag causes the stream to enter one of "half closed" |
| 1038 | // states. |
| 1039 | EndStream bool |
| 1040 | |
| 1041 | // EndHeaders indicates that this frame contains an entire |
| 1042 | // header block and is not followed by any |
| 1043 | // CONTINUATION frames. |
| 1044 | EndHeaders bool |
| 1045 | |
| 1046 | // PadLength is the optional number of bytes of zeros to add |
| 1047 | // to this frame. |
| 1048 | PadLength uint8 |
| 1049 | |
| 1050 | // Priority, if non-zero, includes stream priority information |
| 1051 | // in the HEADER frame. |
| 1052 | Priority PriorityParam |
| 1053 | } |
| 1054 | |
| 1055 | // WriteHeaders writes a single HEADERS frame. |
| 1056 | // |
| 1057 | // This is a low-level header writing method. Encoding headers and |
| 1058 | // splitting them into any necessary CONTINUATION frames is handled |
| 1059 | // elsewhere. |
| 1060 | // |
| 1061 | // It will perform exactly one Write to the underlying Writer. |
| 1062 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 1063 | func (f *Framer) WriteHeaders(p HeadersFrameParam) error { |
| 1064 | if !validStreamID(p.StreamID) && !f.AllowIllegalWrites { |
| 1065 | return errStreamID |
| 1066 | } |
| 1067 | var flags Flags |
| 1068 | if p.PadLength != 0 { |
| 1069 | flags |= FlagHeadersPadded |
| 1070 | } |
| 1071 | if p.EndStream { |
| 1072 | flags |= FlagHeadersEndStream |
| 1073 | } |
| 1074 | if p.EndHeaders { |
| 1075 | flags |= FlagHeadersEndHeaders |
| 1076 | } |
| 1077 | if !p.Priority.IsZero() { |
| 1078 | flags |= FlagHeadersPriority |
| 1079 | } |
| 1080 | f.startWrite(FrameHeaders, flags, p.StreamID) |
| 1081 | if p.PadLength != 0 { |
| 1082 | f.writeByte(p.PadLength) |
| 1083 | } |
| 1084 | if !p.Priority.IsZero() { |
| 1085 | v := p.Priority.StreamDep |
| 1086 | if !validStreamIDOrZero(v) && !f.AllowIllegalWrites { |
| 1087 | return errDepStreamID |
| 1088 | } |
| 1089 | if p.Priority.Exclusive { |
| 1090 | v |= 1 << 31 |
| 1091 | } |
| 1092 | f.writeUint32(v) |
| 1093 | f.writeByte(p.Priority.Weight) |
| 1094 | } |
| 1095 | f.wbuf = append(f.wbuf, p.BlockFragment...) |
| 1096 | f.wbuf = append(f.wbuf, padZeros[:p.PadLength]...) |
| 1097 | return f.endWrite() |
| 1098 | } |
| 1099 | |
| 1100 | // A PriorityFrame specifies the sender-advised priority of a stream. |
| 1101 | // See http://http2.github.io/http2-spec/#rfc.section.6.3 |
| 1102 | type PriorityFrame struct { |
| 1103 | FrameHeader |
| 1104 | PriorityParam |
| 1105 | } |
| 1106 | |
| 1107 | // PriorityParam are the stream prioritzation parameters. |
| 1108 | type PriorityParam struct { |
| 1109 | // StreamDep is a 31-bit stream identifier for the |
| 1110 | // stream that this stream depends on. Zero means no |
| 1111 | // dependency. |
| 1112 | StreamDep uint32 |
| 1113 | |
| 1114 | // Exclusive is whether the dependency is exclusive. |
| 1115 | Exclusive bool |
| 1116 | |
| 1117 | // Weight is the stream's zero-indexed weight. It should be |
| 1118 | // set together with StreamDep, or neither should be set. Per |
| 1119 | // the spec, "Add one to the value to obtain a weight between |
| 1120 | // 1 and 256." |
| 1121 | Weight uint8 |
| 1122 | } |
| 1123 | |
| 1124 | func (p PriorityParam) IsZero() bool { |
| 1125 | return p == PriorityParam{} |
| 1126 | } |
| 1127 | |
| 1128 | func parsePriorityFrame(_ *frameCache, fh FrameHeader, payload []byte) (Frame, error) { |
| 1129 | if fh.StreamID == 0 { |
| 1130 | return nil, connError{ErrCodeProtocol, "PRIORITY frame with stream ID 0"} |
| 1131 | } |
| 1132 | if len(payload) != 5 { |
| 1133 | return nil, connError{ErrCodeFrameSize, fmt.Sprintf("PRIORITY frame payload size was %d; want 5", len(payload))} |
| 1134 | } |
| 1135 | v := binary.BigEndian.Uint32(payload[:4]) |
| 1136 | streamID := v & 0x7fffffff // mask off high bit |
| 1137 | return &PriorityFrame{ |
| 1138 | FrameHeader: fh, |
| 1139 | PriorityParam: PriorityParam{ |
| 1140 | Weight: payload[4], |
| 1141 | StreamDep: streamID, |
| 1142 | Exclusive: streamID != v, // was high bit set? |
| 1143 | }, |
| 1144 | }, nil |
| 1145 | } |
| 1146 | |
| 1147 | // WritePriority writes a PRIORITY frame. |
| 1148 | // |
| 1149 | // It will perform exactly one Write to the underlying Writer. |
| 1150 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 1151 | func (f *Framer) WritePriority(streamID uint32, p PriorityParam) error { |
| 1152 | if !validStreamID(streamID) && !f.AllowIllegalWrites { |
| 1153 | return errStreamID |
| 1154 | } |
| 1155 | if !validStreamIDOrZero(p.StreamDep) { |
| 1156 | return errDepStreamID |
| 1157 | } |
| 1158 | f.startWrite(FramePriority, 0, streamID) |
| 1159 | v := p.StreamDep |
| 1160 | if p.Exclusive { |
| 1161 | v |= 1 << 31 |
| 1162 | } |
| 1163 | f.writeUint32(v) |
| 1164 | f.writeByte(p.Weight) |
| 1165 | return f.endWrite() |
| 1166 | } |
| 1167 | |
| 1168 | // A RSTStreamFrame allows for abnormal termination of a stream. |
| 1169 | // See http://http2.github.io/http2-spec/#rfc.section.6.4 |
| 1170 | type RSTStreamFrame struct { |
| 1171 | FrameHeader |
| 1172 | ErrCode ErrCode |
| 1173 | } |
| 1174 | |
| 1175 | func parseRSTStreamFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 1176 | if len(p) != 4 { |
| 1177 | return nil, ConnectionError(ErrCodeFrameSize) |
| 1178 | } |
| 1179 | if fh.StreamID == 0 { |
| 1180 | return nil, ConnectionError(ErrCodeProtocol) |
| 1181 | } |
| 1182 | return &RSTStreamFrame{fh, ErrCode(binary.BigEndian.Uint32(p[:4]))}, nil |
| 1183 | } |
| 1184 | |
| 1185 | // WriteRSTStream writes a RST_STREAM frame. |
| 1186 | // |
| 1187 | // It will perform exactly one Write to the underlying Writer. |
| 1188 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 1189 | func (f *Framer) WriteRSTStream(streamID uint32, code ErrCode) error { |
| 1190 | if !validStreamID(streamID) && !f.AllowIllegalWrites { |
| 1191 | return errStreamID |
| 1192 | } |
| 1193 | f.startWrite(FrameRSTStream, 0, streamID) |
| 1194 | f.writeUint32(uint32(code)) |
| 1195 | return f.endWrite() |
| 1196 | } |
| 1197 | |
| 1198 | // A ContinuationFrame is used to continue a sequence of header block fragments. |
| 1199 | // See http://http2.github.io/http2-spec/#rfc.section.6.10 |
| 1200 | type ContinuationFrame struct { |
| 1201 | FrameHeader |
| 1202 | headerFragBuf []byte |
| 1203 | } |
| 1204 | |
| 1205 | func parseContinuationFrame(_ *frameCache, fh FrameHeader, p []byte) (Frame, error) { |
| 1206 | if fh.StreamID == 0 { |
| 1207 | return nil, connError{ErrCodeProtocol, "CONTINUATION frame with stream ID 0"} |
| 1208 | } |
| 1209 | return &ContinuationFrame{fh, p}, nil |
| 1210 | } |
| 1211 | |
| 1212 | func (f *ContinuationFrame) HeaderBlockFragment() []byte { |
| 1213 | f.checkValid() |
| 1214 | return f.headerFragBuf |
| 1215 | } |
| 1216 | |
| 1217 | func (f *ContinuationFrame) HeadersEnded() bool { |
| 1218 | return f.FrameHeader.Flags.Has(FlagContinuationEndHeaders) |
| 1219 | } |
| 1220 | |
| 1221 | // WriteContinuation writes a CONTINUATION frame. |
| 1222 | // |
| 1223 | // It will perform exactly one Write to the underlying Writer. |
| 1224 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 1225 | func (f *Framer) WriteContinuation(streamID uint32, endHeaders bool, headerBlockFragment []byte) error { |
| 1226 | if !validStreamID(streamID) && !f.AllowIllegalWrites { |
| 1227 | return errStreamID |
| 1228 | } |
| 1229 | var flags Flags |
| 1230 | if endHeaders { |
| 1231 | flags |= FlagContinuationEndHeaders |
| 1232 | } |
| 1233 | f.startWrite(FrameContinuation, flags, streamID) |
| 1234 | f.wbuf = append(f.wbuf, headerBlockFragment...) |
| 1235 | return f.endWrite() |
| 1236 | } |
| 1237 | |
| 1238 | // A PushPromiseFrame is used to initiate a server stream. |
| 1239 | // See http://http2.github.io/http2-spec/#rfc.section.6.6 |
| 1240 | type PushPromiseFrame struct { |
| 1241 | FrameHeader |
| 1242 | PromiseID uint32 |
| 1243 | headerFragBuf []byte // not owned |
| 1244 | } |
| 1245 | |
| 1246 | func (f *PushPromiseFrame) HeaderBlockFragment() []byte { |
| 1247 | f.checkValid() |
| 1248 | return f.headerFragBuf |
| 1249 | } |
| 1250 | |
| 1251 | func (f *PushPromiseFrame) HeadersEnded() bool { |
| 1252 | return f.FrameHeader.Flags.Has(FlagPushPromiseEndHeaders) |
| 1253 | } |
| 1254 | |
| 1255 | func parsePushPromise(_ *frameCache, fh FrameHeader, p []byte) (_ Frame, err error) { |
| 1256 | pp := &PushPromiseFrame{ |
| 1257 | FrameHeader: fh, |
| 1258 | } |
| 1259 | if pp.StreamID == 0 { |
| 1260 | // PUSH_PROMISE frames MUST be associated with an existing, |
| 1261 | // peer-initiated stream. The stream identifier of a |
| 1262 | // PUSH_PROMISE frame indicates the stream it is associated |
| 1263 | // with. If the stream identifier field specifies the value |
| 1264 | // 0x0, a recipient MUST respond with a connection error |
| 1265 | // (Section 5.4.1) of type PROTOCOL_ERROR. |
| 1266 | return nil, ConnectionError(ErrCodeProtocol) |
| 1267 | } |
| 1268 | // The PUSH_PROMISE frame includes optional padding. |
| 1269 | // Padding fields and flags are identical to those defined for DATA frames |
| 1270 | var padLength uint8 |
| 1271 | if fh.Flags.Has(FlagPushPromisePadded) { |
| 1272 | if p, padLength, err = readByte(p); err != nil { |
| 1273 | return |
| 1274 | } |
| 1275 | } |
| 1276 | |
| 1277 | p, pp.PromiseID, err = readUint32(p) |
| 1278 | if err != nil { |
| 1279 | return |
| 1280 | } |
| 1281 | pp.PromiseID = pp.PromiseID & (1<<31 - 1) |
| 1282 | |
| 1283 | if int(padLength) > len(p) { |
| 1284 | // like the DATA frame, error out if padding is longer than the body. |
| 1285 | return nil, ConnectionError(ErrCodeProtocol) |
| 1286 | } |
| 1287 | pp.headerFragBuf = p[:len(p)-int(padLength)] |
| 1288 | return pp, nil |
| 1289 | } |
| 1290 | |
| 1291 | // PushPromiseParam are the parameters for writing a PUSH_PROMISE frame. |
| 1292 | type PushPromiseParam struct { |
| 1293 | // StreamID is the required Stream ID to initiate. |
| 1294 | StreamID uint32 |
| 1295 | |
| 1296 | // PromiseID is the required Stream ID which this |
| 1297 | // Push Promises |
| 1298 | PromiseID uint32 |
| 1299 | |
| 1300 | // BlockFragment is part (or all) of a Header Block. |
| 1301 | BlockFragment []byte |
| 1302 | |
| 1303 | // EndHeaders indicates that this frame contains an entire |
| 1304 | // header block and is not followed by any |
| 1305 | // CONTINUATION frames. |
| 1306 | EndHeaders bool |
| 1307 | |
| 1308 | // PadLength is the optional number of bytes of zeros to add |
| 1309 | // to this frame. |
| 1310 | PadLength uint8 |
| 1311 | } |
| 1312 | |
| 1313 | // WritePushPromise writes a single PushPromise Frame. |
| 1314 | // |
| 1315 | // As with Header Frames, This is the low level call for writing |
| 1316 | // individual frames. Continuation frames are handled elsewhere. |
| 1317 | // |
| 1318 | // It will perform exactly one Write to the underlying Writer. |
| 1319 | // It is the caller's responsibility to not call other Write methods concurrently. |
| 1320 | func (f *Framer) WritePushPromise(p PushPromiseParam) error { |
| 1321 | if !validStreamID(p.StreamID) && !f.AllowIllegalWrites { |
| 1322 | return errStreamID |
| 1323 | } |
| 1324 | var flags Flags |
| 1325 | if p.PadLength != 0 { |
| 1326 | flags |= FlagPushPromisePadded |
| 1327 | } |
| 1328 | if p.EndHeaders { |
| 1329 | flags |= FlagPushPromiseEndHeaders |
| 1330 | } |
| 1331 | f.startWrite(FramePushPromise, flags, p.StreamID) |
| 1332 | if p.PadLength != 0 { |
| 1333 | f.writeByte(p.PadLength) |
| 1334 | } |
| 1335 | if !validStreamID(p.PromiseID) && !f.AllowIllegalWrites { |
| 1336 | return errStreamID |
| 1337 | } |
| 1338 | f.writeUint32(p.PromiseID) |
| 1339 | f.wbuf = append(f.wbuf, p.BlockFragment...) |
| 1340 | f.wbuf = append(f.wbuf, padZeros[:p.PadLength]...) |
| 1341 | return f.endWrite() |
| 1342 | } |
| 1343 | |
| 1344 | // WriteRawFrame writes a raw frame. This can be used to write |
| 1345 | // extension frames unknown to this package. |
| 1346 | func (f *Framer) WriteRawFrame(t FrameType, flags Flags, streamID uint32, payload []byte) error { |
| 1347 | f.startWrite(t, flags, streamID) |
| 1348 | f.writeBytes(payload) |
| 1349 | return f.endWrite() |
| 1350 | } |
| 1351 | |
| 1352 | func readByte(p []byte) (remain []byte, b byte, err error) { |
| 1353 | if len(p) == 0 { |
| 1354 | return nil, 0, io.ErrUnexpectedEOF |
| 1355 | } |
| 1356 | return p[1:], p[0], nil |
| 1357 | } |
| 1358 | |
| 1359 | func readUint32(p []byte) (remain []byte, v uint32, err error) { |
| 1360 | if len(p) < 4 { |
| 1361 | return nil, 0, io.ErrUnexpectedEOF |
| 1362 | } |
| 1363 | return p[4:], binary.BigEndian.Uint32(p[:4]), nil |
| 1364 | } |
| 1365 | |
| 1366 | type streamEnder interface { |
| 1367 | StreamEnded() bool |
| 1368 | } |
| 1369 | |
| 1370 | type headersEnder interface { |
| 1371 | HeadersEnded() bool |
| 1372 | } |
| 1373 | |
| 1374 | type headersOrContinuation interface { |
| 1375 | headersEnder |
| 1376 | HeaderBlockFragment() []byte |
| 1377 | } |
| 1378 | |
| 1379 | // A MetaHeadersFrame is the representation of one HEADERS frame and |
| 1380 | // zero or more contiguous CONTINUATION frames and the decoding of |
| 1381 | // their HPACK-encoded contents. |
| 1382 | // |
| 1383 | // This type of frame does not appear on the wire and is only returned |
| 1384 | // by the Framer when Framer.ReadMetaHeaders is set. |
| 1385 | type MetaHeadersFrame struct { |
| 1386 | *HeadersFrame |
| 1387 | |
| 1388 | // Fields are the fields contained in the HEADERS and |
| 1389 | // CONTINUATION frames. The underlying slice is owned by the |
| 1390 | // Framer and must not be retained after the next call to |
| 1391 | // ReadFrame. |
| 1392 | // |
| 1393 | // Fields are guaranteed to be in the correct http2 order and |
| 1394 | // not have unknown pseudo header fields or invalid header |
| 1395 | // field names or values. Required pseudo header fields may be |
| 1396 | // missing, however. Use the MetaHeadersFrame.Pseudo accessor |
| 1397 | // method access pseudo headers. |
| 1398 | Fields []hpack.HeaderField |
| 1399 | |
| 1400 | // Truncated is whether the max header list size limit was hit |
| 1401 | // and Fields is incomplete. The hpack decoder state is still |
| 1402 | // valid, however. |
| 1403 | Truncated bool |
| 1404 | } |
| 1405 | |
| 1406 | // PseudoValue returns the given pseudo header field's value. |
| 1407 | // The provided pseudo field should not contain the leading colon. |
| 1408 | func (mh *MetaHeadersFrame) PseudoValue(pseudo string) string { |
| 1409 | for _, hf := range mh.Fields { |
| 1410 | if !hf.IsPseudo() { |
| 1411 | return "" |
| 1412 | } |
| 1413 | if hf.Name[1:] == pseudo { |
| 1414 | return hf.Value |
| 1415 | } |
| 1416 | } |
| 1417 | return "" |
| 1418 | } |
| 1419 | |
| 1420 | // RegularFields returns the regular (non-pseudo) header fields of mh. |
| 1421 | // The caller does not own the returned slice. |
| 1422 | func (mh *MetaHeadersFrame) RegularFields() []hpack.HeaderField { |
| 1423 | for i, hf := range mh.Fields { |
| 1424 | if !hf.IsPseudo() { |
| 1425 | return mh.Fields[i:] |
| 1426 | } |
| 1427 | } |
| 1428 | return nil |
| 1429 | } |
| 1430 | |
| 1431 | // PseudoFields returns the pseudo header fields of mh. |
| 1432 | // The caller does not own the returned slice. |
| 1433 | func (mh *MetaHeadersFrame) PseudoFields() []hpack.HeaderField { |
| 1434 | for i, hf := range mh.Fields { |
| 1435 | if !hf.IsPseudo() { |
| 1436 | return mh.Fields[:i] |
| 1437 | } |
| 1438 | } |
| 1439 | return mh.Fields |
| 1440 | } |
| 1441 | |
| 1442 | func (mh *MetaHeadersFrame) checkPseudos() error { |
| 1443 | var isRequest, isResponse bool |
| 1444 | pf := mh.PseudoFields() |
| 1445 | for i, hf := range pf { |
| 1446 | switch hf.Name { |
| 1447 | case ":method", ":path", ":scheme", ":authority": |
| 1448 | isRequest = true |
| 1449 | case ":status": |
| 1450 | isResponse = true |
| 1451 | default: |
| 1452 | return pseudoHeaderError(hf.Name) |
| 1453 | } |
| 1454 | // Check for duplicates. |
| 1455 | // This would be a bad algorithm, but N is 4. |
| 1456 | // And this doesn't allocate. |
| 1457 | for _, hf2 := range pf[:i] { |
| 1458 | if hf.Name == hf2.Name { |
| 1459 | return duplicatePseudoHeaderError(hf.Name) |
| 1460 | } |
| 1461 | } |
| 1462 | } |
| 1463 | if isRequest && isResponse { |
| 1464 | return errMixPseudoHeaderTypes |
| 1465 | } |
| 1466 | return nil |
| 1467 | } |
| 1468 | |
| 1469 | func (fr *Framer) maxHeaderStringLen() int { |
| 1470 | v := fr.maxHeaderListSize() |
| 1471 | if uint32(int(v)) == v { |
| 1472 | return int(v) |
| 1473 | } |
| 1474 | // They had a crazy big number for MaxHeaderBytes anyway, |
| 1475 | // so give them unlimited header lengths: |
| 1476 | return 0 |
| 1477 | } |
| 1478 | |
| 1479 | // readMetaFrame returns 0 or more CONTINUATION frames from fr and |
| 1480 | // merge them into the provided hf and returns a MetaHeadersFrame |
| 1481 | // with the decoded hpack values. |
| 1482 | func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) { |
| 1483 | if fr.AllowIllegalReads { |
| 1484 | return nil, errors.New("illegal use of AllowIllegalReads with ReadMetaHeaders") |
| 1485 | } |
| 1486 | mh := &MetaHeadersFrame{ |
| 1487 | HeadersFrame: hf, |
| 1488 | } |
| 1489 | var remainSize = fr.maxHeaderListSize() |
| 1490 | var sawRegular bool |
| 1491 | |
| 1492 | var invalid error // pseudo header field errors |
| 1493 | hdec := fr.ReadMetaHeaders |
| 1494 | hdec.SetEmitEnabled(true) |
| 1495 | hdec.SetMaxStringLength(fr.maxHeaderStringLen()) |
| 1496 | hdec.SetEmitFunc(func(hf hpack.HeaderField) { |
| 1497 | if VerboseLogs && fr.logReads { |
| 1498 | fr.debugReadLoggerf("http2: decoded hpack field %+v", hf) |
| 1499 | } |
| 1500 | if !httpguts.ValidHeaderFieldValue(hf.Value) { |
| 1501 | invalid = headerFieldValueError(hf.Value) |
| 1502 | } |
| 1503 | isPseudo := strings.HasPrefix(hf.Name, ":") |
| 1504 | if isPseudo { |
| 1505 | if sawRegular { |
| 1506 | invalid = errPseudoAfterRegular |
| 1507 | } |
| 1508 | } else { |
| 1509 | sawRegular = true |
| 1510 | if !validWireHeaderFieldName(hf.Name) { |
| 1511 | invalid = headerFieldNameError(hf.Name) |
| 1512 | } |
| 1513 | } |
| 1514 | |
| 1515 | if invalid != nil { |
| 1516 | hdec.SetEmitEnabled(false) |
| 1517 | return |
| 1518 | } |
| 1519 | |
| 1520 | size := hf.Size() |
| 1521 | if size > remainSize { |
| 1522 | hdec.SetEmitEnabled(false) |
| 1523 | mh.Truncated = true |
| 1524 | return |
| 1525 | } |
| 1526 | remainSize -= size |
| 1527 | |
| 1528 | mh.Fields = append(mh.Fields, hf) |
| 1529 | }) |
| 1530 | // Lose reference to MetaHeadersFrame: |
| 1531 | defer hdec.SetEmitFunc(func(hf hpack.HeaderField) {}) |
| 1532 | |
| 1533 | var hc headersOrContinuation = hf |
| 1534 | for { |
| 1535 | frag := hc.HeaderBlockFragment() |
| 1536 | if _, err := hdec.Write(frag); err != nil { |
| 1537 | return nil, ConnectionError(ErrCodeCompression) |
| 1538 | } |
| 1539 | |
| 1540 | if hc.HeadersEnded() { |
| 1541 | break |
| 1542 | } |
| 1543 | if f, err := fr.ReadFrame(); err != nil { |
| 1544 | return nil, err |
| 1545 | } else { |
| 1546 | hc = f.(*ContinuationFrame) // guaranteed by checkFrameOrder |
| 1547 | } |
| 1548 | } |
| 1549 | |
| 1550 | mh.HeadersFrame.headerFragBuf = nil |
| 1551 | mh.HeadersFrame.invalidate() |
| 1552 | |
| 1553 | if err := hdec.Close(); err != nil { |
| 1554 | return nil, ConnectionError(ErrCodeCompression) |
| 1555 | } |
| 1556 | if invalid != nil { |
| 1557 | fr.errDetail = invalid |
| 1558 | if VerboseLogs { |
| 1559 | log.Printf("http2: invalid header: %v", invalid) |
| 1560 | } |
| 1561 | return nil, StreamError{mh.StreamID, ErrCodeProtocol, invalid} |
| 1562 | } |
| 1563 | if err := mh.checkPseudos(); err != nil { |
| 1564 | fr.errDetail = err |
| 1565 | if VerboseLogs { |
| 1566 | log.Printf("http2: invalid pseudo headers: %v", err) |
| 1567 | } |
| 1568 | return nil, StreamError{mh.StreamID, ErrCodeProtocol, err} |
| 1569 | } |
| 1570 | return mh, nil |
| 1571 | } |
| 1572 | |
| 1573 | func summarizeFrame(f Frame) string { |
| 1574 | var buf bytes.Buffer |
| 1575 | f.Header().writeDebug(&buf) |
| 1576 | switch f := f.(type) { |
| 1577 | case *SettingsFrame: |
| 1578 | n := 0 |
| 1579 | f.ForeachSetting(func(s Setting) error { |
| 1580 | n++ |
| 1581 | if n == 1 { |
| 1582 | buf.WriteString(", settings:") |
| 1583 | } |
| 1584 | fmt.Fprintf(&buf, " %v=%v,", s.ID, s.Val) |
| 1585 | return nil |
| 1586 | }) |
| 1587 | if n > 0 { |
| 1588 | buf.Truncate(buf.Len() - 1) // remove trailing comma |
| 1589 | } |
| 1590 | case *DataFrame: |
| 1591 | data := f.Data() |
| 1592 | const max = 256 |
| 1593 | if len(data) > max { |
| 1594 | data = data[:max] |
| 1595 | } |
| 1596 | fmt.Fprintf(&buf, " data=%q", data) |
| 1597 | if len(f.Data()) > max { |
| 1598 | fmt.Fprintf(&buf, " (%d bytes omitted)", len(f.Data())-max) |
| 1599 | } |
| 1600 | case *WindowUpdateFrame: |
| 1601 | if f.StreamID == 0 { |
| 1602 | buf.WriteString(" (conn)") |
| 1603 | } |
| 1604 | fmt.Fprintf(&buf, " incr=%v", f.Increment) |
| 1605 | case *PingFrame: |
| 1606 | fmt.Fprintf(&buf, " ping=%q", f.Data[:]) |
| 1607 | case *GoAwayFrame: |
| 1608 | fmt.Fprintf(&buf, " LastStreamID=%v ErrCode=%v Debug=%q", |
| 1609 | f.LastStreamID, f.ErrCode, f.debugData) |
| 1610 | case *RSTStreamFrame: |
| 1611 | fmt.Fprintf(&buf, " ErrCode=%v", f.ErrCode) |
| 1612 | } |
| 1613 | return buf.String() |
| 1614 | } |