From a18a13fb09eac00cdacf1f74080524182b7243de Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Mon, 6 Jun 2016 00:55:30 +0100 Subject: update vendor --- vendor/golang.org/x/net/http2/frame.go | 1507 ++++++++++++++++++++++++++++++++ 1 file changed, 1507 insertions(+) create mode 100644 vendor/golang.org/x/net/http2/frame.go (limited to 'vendor/golang.org/x/net/http2/frame.go') diff --git a/vendor/golang.org/x/net/http2/frame.go b/vendor/golang.org/x/net/http2/frame.go new file mode 100644 index 0000000..88067dc --- /dev/null +++ b/vendor/golang.org/x/net/http2/frame.go @@ -0,0 +1,1507 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package http2 + +import ( + "bytes" + "encoding/binary" + "errors" + "fmt" + "io" + "log" + "strings" + "sync" + + "golang.org/x/net/http2/hpack" + "golang.org/x/net/lex/httplex" +) + +const frameHeaderLen = 9 + +var padZeros = make([]byte, 255) // zeros for padding + +// A FrameType is a registered frame type as defined in +// http://http2.github.io/http2-spec/#rfc.section.11.2 +type FrameType uint8 + +const ( + FrameData FrameType = 0x0 + FrameHeaders FrameType = 0x1 + FramePriority FrameType = 0x2 + FrameRSTStream FrameType = 0x3 + FrameSettings FrameType = 0x4 + FramePushPromise FrameType = 0x5 + FramePing FrameType = 0x6 + FrameGoAway FrameType = 0x7 + FrameWindowUpdate FrameType = 0x8 + FrameContinuation FrameType = 0x9 +) + +var frameName = map[FrameType]string{ + FrameData: "DATA", + FrameHeaders: "HEADERS", + FramePriority: "PRIORITY", + FrameRSTStream: "RST_STREAM", + FrameSettings: "SETTINGS", + FramePushPromise: "PUSH_PROMISE", + FramePing: "PING", + FrameGoAway: "GOAWAY", + FrameWindowUpdate: "WINDOW_UPDATE", + FrameContinuation: "CONTINUATION", +} + +func (t FrameType) String() string { + if s, ok := frameName[t]; ok { + return s + } + return fmt.Sprintf("UNKNOWN_FRAME_TYPE_%d", uint8(t)) +} + +// Flags is a bitmask of HTTP/2 flags. +// The meaning of flags varies depending on the frame type. +type Flags uint8 + +// Has reports whether f contains all (0 or more) flags in v. +func (f Flags) Has(v Flags) bool { + return (f & v) == v +} + +// Frame-specific FrameHeader flag bits. +const ( + // Data Frame + FlagDataEndStream Flags = 0x1 + FlagDataPadded Flags = 0x8 + + // Headers Frame + FlagHeadersEndStream Flags = 0x1 + FlagHeadersEndHeaders Flags = 0x4 + FlagHeadersPadded Flags = 0x8 + FlagHeadersPriority Flags = 0x20 + + // Settings Frame + FlagSettingsAck Flags = 0x1 + + // Ping Frame + FlagPingAck Flags = 0x1 + + // Continuation Frame + FlagContinuationEndHeaders Flags = 0x4 + + FlagPushPromiseEndHeaders Flags = 0x4 + FlagPushPromisePadded Flags = 0x8 +) + +var flagName = map[FrameType]map[Flags]string{ + FrameData: { + FlagDataEndStream: "END_STREAM", + FlagDataPadded: "PADDED", + }, + FrameHeaders: { + FlagHeadersEndStream: "END_STREAM", + FlagHeadersEndHeaders: "END_HEADERS", + FlagHeadersPadded: "PADDED", + FlagHeadersPriority: "PRIORITY", + }, + FrameSettings: { + FlagSettingsAck: "ACK", + }, + FramePing: { + FlagPingAck: "ACK", + }, + FrameContinuation: { + FlagContinuationEndHeaders: "END_HEADERS", + }, + FramePushPromise: { + FlagPushPromiseEndHeaders: "END_HEADERS", + FlagPushPromisePadded: "PADDED", + }, +} + +// a frameParser parses a frame given its FrameHeader and payload +// bytes. The length of payload will always equal fh.Length (which +// might be 0). +type frameParser func(fh FrameHeader, payload []byte) (Frame, error) + +var frameParsers = map[FrameType]frameParser{ + FrameData: parseDataFrame, + FrameHeaders: parseHeadersFrame, + FramePriority: parsePriorityFrame, + FrameRSTStream: parseRSTStreamFrame, + FrameSettings: parseSettingsFrame, + FramePushPromise: parsePushPromise, + FramePing: parsePingFrame, + FrameGoAway: parseGoAwayFrame, + FrameWindowUpdate: parseWindowUpdateFrame, + FrameContinuation: parseContinuationFrame, +} + +func typeFrameParser(t FrameType) frameParser { + if f := frameParsers[t]; f != nil { + return f + } + return parseUnknownFrame +} + +// A FrameHeader is the 9 byte header of all HTTP/2 frames. +// +// See http://http2.github.io/http2-spec/#FrameHeader +type FrameHeader struct { + valid bool // caller can access []byte fields in the Frame + + // Type is the 1 byte frame type. There are ten standard frame + // types, but extension frame types may be written by WriteRawFrame + // and will be returned by ReadFrame (as UnknownFrame). + Type FrameType + + // Flags are the 1 byte of 8 potential bit flags per frame. + // They are specific to the frame type. + Flags Flags + + // Length is the length of the frame, not including the 9 byte header. + // The maximum size is one byte less than 16MB (uint24), but only + // frames up to 16KB are allowed without peer agreement. + Length uint32 + + // StreamID is which stream this frame is for. Certain frames + // are not stream-specific, in which case this field is 0. + StreamID uint32 +} + +// Header returns h. It exists so FrameHeaders can be embedded in other +// specific frame types and implement the Frame interface. +func (h FrameHeader) Header() FrameHeader { return h } + +func (h FrameHeader) String() string { + var buf bytes.Buffer + buf.WriteString("[FrameHeader ") + h.writeDebug(&buf) + buf.WriteByte(']') + return buf.String() +} + +func (h FrameHeader) writeDebug(buf *bytes.Buffer) { + buf.WriteString(h.Type.String()) + if h.Flags != 0 { + buf.WriteString(" flags=") + set := 0 + for i := uint8(0); i < 8; i++ { + if h.Flags&(1< 1 { + buf.WriteByte('|') + } + name := flagName[h.Type][Flags(1<>24), + byte(streamID>>16), + byte(streamID>>8), + byte(streamID)) +} + +func (f *Framer) endWrite() error { + // Now that we know the final size, fill in the FrameHeader in + // the space previously reserved for it. Abuse append. + length := len(f.wbuf) - frameHeaderLen + if length >= (1 << 24) { + return ErrFrameTooLarge + } + _ = append(f.wbuf[:0], + byte(length>>16), + byte(length>>8), + byte(length)) + if logFrameWrites { + f.logWrite() + } + + n, err := f.w.Write(f.wbuf) + if err == nil && n != len(f.wbuf) { + err = io.ErrShortWrite + } + return err +} + +func (f *Framer) logWrite() { + if f.debugFramer == nil { + f.debugFramerBuf = new(bytes.Buffer) + f.debugFramer = NewFramer(nil, f.debugFramerBuf) + f.debugFramer.logReads = false // we log it ourselves, saying "wrote" below + // Let us read anything, even if we accidentally wrote it + // in the wrong order: + f.debugFramer.AllowIllegalReads = true + } + f.debugFramerBuf.Write(f.wbuf) + fr, err := f.debugFramer.ReadFrame() + if err != nil { + log.Printf("http2: Framer %p: failed to decode just-written frame", f) + return + } + log.Printf("http2: Framer %p: wrote %v", f, summarizeFrame(fr)) +} + +func (f *Framer) writeByte(v byte) { f.wbuf = append(f.wbuf, v) } +func (f *Framer) writeBytes(v []byte) { f.wbuf = append(f.wbuf, v...) } +func (f *Framer) writeUint16(v uint16) { f.wbuf = append(f.wbuf, byte(v>>8), byte(v)) } +func (f *Framer) writeUint32(v uint32) { + f.wbuf = append(f.wbuf, byte(v>>24), byte(v>>16), byte(v>>8), byte(v)) +} + +const ( + minMaxFrameSize = 1 << 14 + maxFrameSize = 1<<24 - 1 +) + +// NewFramer returns a Framer that writes frames to w and reads them from r. +func NewFramer(w io.Writer, r io.Reader) *Framer { + fr := &Framer{ + w: w, + r: r, + logReads: logFrameReads, + } + fr.getReadBuf = func(size uint32) []byte { + if cap(fr.readBuf) >= int(size) { + return fr.readBuf[:size] + } + fr.readBuf = make([]byte, size) + return fr.readBuf + } + fr.SetMaxReadFrameSize(maxFrameSize) + return fr +} + +// SetMaxReadFrameSize sets the maximum size of a frame +// that will be read by a subsequent call to ReadFrame. +// It is the caller's responsibility to advertise this +// limit with a SETTINGS frame. +func (fr *Framer) SetMaxReadFrameSize(v uint32) { + if v > maxFrameSize { + v = maxFrameSize + } + fr.maxReadSize = v +} + +// ErrorDetail returns a more detailed error of the last error +// returned by Framer.ReadFrame. For instance, if ReadFrame +// returns a StreamError with code PROTOCOL_ERROR, ErrorDetail +// will say exactly what was invalid. ErrorDetail is not guaranteed +// to return a non-nil value and like the rest of the http2 package, +// its return value is not protected by an API compatibility promise. +// ErrorDetail is reset after the next call to ReadFrame. +func (fr *Framer) ErrorDetail() error { + return fr.errDetail +} + +// ErrFrameTooLarge is returned from Framer.ReadFrame when the peer +// sends a frame that is larger than declared with SetMaxReadFrameSize. +var ErrFrameTooLarge = errors.New("http2: frame too large") + +// terminalReadFrameError reports whether err is an unrecoverable +// error from ReadFrame and no other frames should be read. +func terminalReadFrameError(err error) bool { + if _, ok := err.(StreamError); ok { + return false + } + return err != nil +} + +// ReadFrame reads a single frame. The returned Frame is only valid +// until the next call to ReadFrame. +// +// If the frame is larger than previously set with SetMaxReadFrameSize, the +// returned error is ErrFrameTooLarge. Other errors may be of type +// ConnectionError, StreamError, or anything else from from the underlying +// reader. +func (fr *Framer) ReadFrame() (Frame, error) { + fr.errDetail = nil + if fr.lastFrame != nil { + fr.lastFrame.invalidate() + } + fh, err := readFrameHeader(fr.headerBuf[:], fr.r) + if err != nil { + return nil, err + } + if fh.Length > fr.maxReadSize { + return nil, ErrFrameTooLarge + } + payload := fr.getReadBuf(fh.Length) + if _, err := io.ReadFull(fr.r, payload); err != nil { + return nil, err + } + f, err := typeFrameParser(fh.Type)(fh, payload) + if err != nil { + if ce, ok := err.(connError); ok { + return nil, fr.connError(ce.Code, ce.Reason) + } + return nil, err + } + if err := fr.checkFrameOrder(f); err != nil { + return nil, err + } + if fr.logReads { + log.Printf("http2: Framer %p: read %v", fr, summarizeFrame(f)) + } + if fh.Type == FrameHeaders && fr.ReadMetaHeaders != nil { + return fr.readMetaFrame(f.(*HeadersFrame)) + } + return f, nil +} + +// connError returns ConnectionError(code) but first +// stashes away a public reason to the caller can optionally relay it +// to the peer before hanging up on them. This might help others debug +// their implementations. +func (fr *Framer) connError(code ErrCode, reason string) error { + fr.errDetail = errors.New(reason) + return ConnectionError(code) +} + +// checkFrameOrder reports an error if f is an invalid frame to return +// next from ReadFrame. Mostly it checks whether HEADERS and +// CONTINUATION frames are contiguous. +func (fr *Framer) checkFrameOrder(f Frame) error { + last := fr.lastFrame + fr.lastFrame = f + if fr.AllowIllegalReads { + return nil + } + + fh := f.Header() + if fr.lastHeaderStream != 0 { + if fh.Type != FrameContinuation { + return fr.connError(ErrCodeProtocol, + fmt.Sprintf("got %s for stream %d; expected CONTINUATION following %s for stream %d", + fh.Type, fh.StreamID, + last.Header().Type, fr.lastHeaderStream)) + } + if fh.StreamID != fr.lastHeaderStream { + return fr.connError(ErrCodeProtocol, + fmt.Sprintf("got CONTINUATION for stream %d; expected stream %d", + fh.StreamID, fr.lastHeaderStream)) + } + } else if fh.Type == FrameContinuation { + return fr.connError(ErrCodeProtocol, fmt.Sprintf("unexpected CONTINUATION for stream %d", fh.StreamID)) + } + + switch fh.Type { + case FrameHeaders, FrameContinuation: + if fh.Flags.Has(FlagHeadersEndHeaders) { + fr.lastHeaderStream = 0 + } else { + fr.lastHeaderStream = fh.StreamID + } + } + + return nil +} + +// A DataFrame conveys arbitrary, variable-length sequences of octets +// associated with a stream. +// See http://http2.github.io/http2-spec/#rfc.section.6.1 +type DataFrame struct { + FrameHeader + data []byte +} + +func (f *DataFrame) StreamEnded() bool { + return f.FrameHeader.Flags.Has(FlagDataEndStream) +} + +// Data returns the frame's data octets, not including any padding +// size byte or padding suffix bytes. +// The caller must not retain the returned memory past the next +// call to ReadFrame. +func (f *DataFrame) Data() []byte { + f.checkValid() + return f.data +} + +func parseDataFrame(fh FrameHeader, payload []byte) (Frame, error) { + if fh.StreamID == 0 { + // DATA frames MUST be associated with a stream. If a + // DATA frame is received whose stream identifier + // field is 0x0, the recipient MUST respond with a + // connection error (Section 5.4.1) of type + // PROTOCOL_ERROR. + return nil, connError{ErrCodeProtocol, "DATA frame with stream ID 0"} + } + f := &DataFrame{ + FrameHeader: fh, + } + var padSize byte + if fh.Flags.Has(FlagDataPadded) { + var err error + payload, padSize, err = readByte(payload) + if err != nil { + return nil, err + } + } + if int(padSize) > len(payload) { + // If the length of the padding is greater than the + // length of the frame payload, the recipient MUST + // treat this as a connection error. + // Filed: https://github.com/http2/http2-spec/issues/610 + return nil, connError{ErrCodeProtocol, "pad size larger than data payload"} + } + f.data = payload[:len(payload)-int(padSize)] + return f, nil +} + +var ( + errStreamID = errors.New("invalid stream ID") + errDepStreamID = errors.New("invalid dependent stream ID") +) + +func validStreamIDOrZero(streamID uint32) bool { + return streamID&(1<<31) == 0 +} + +func validStreamID(streamID uint32) bool { + return streamID != 0 && streamID&(1<<31) == 0 +} + +// WriteData writes a DATA frame. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteData(streamID uint32, endStream bool, data []byte) error { + // TODO: ignoring padding for now. will add when somebody cares. + if !validStreamID(streamID) && !f.AllowIllegalWrites { + return errStreamID + } + var flags Flags + if endStream { + flags |= FlagDataEndStream + } + f.startWrite(FrameData, flags, streamID) + f.wbuf = append(f.wbuf, data...) + return f.endWrite() +} + +// A SettingsFrame conveys configuration parameters that affect how +// endpoints communicate, such as preferences and constraints on peer +// behavior. +// +// See http://http2.github.io/http2-spec/#SETTINGS +type SettingsFrame struct { + FrameHeader + p []byte +} + +func parseSettingsFrame(fh FrameHeader, p []byte) (Frame, error) { + if fh.Flags.Has(FlagSettingsAck) && fh.Length > 0 { + // When this (ACK 0x1) bit is set, the payload of the + // SETTINGS frame MUST be empty. Receipt of a + // SETTINGS frame with the ACK flag set and a length + // field value other than 0 MUST be treated as a + // connection error (Section 5.4.1) of type + // FRAME_SIZE_ERROR. + return nil, ConnectionError(ErrCodeFrameSize) + } + if fh.StreamID != 0 { + // SETTINGS frames always apply to a connection, + // never a single stream. The stream identifier for a + // SETTINGS frame MUST be zero (0x0). If an endpoint + // receives a SETTINGS frame whose stream identifier + // field is anything other than 0x0, the endpoint MUST + // respond with a connection error (Section 5.4.1) of + // type PROTOCOL_ERROR. + return nil, ConnectionError(ErrCodeProtocol) + } + if len(p)%6 != 0 { + // Expecting even number of 6 byte settings. + return nil, ConnectionError(ErrCodeFrameSize) + } + f := &SettingsFrame{FrameHeader: fh, p: p} + if v, ok := f.Value(SettingInitialWindowSize); ok && v > (1<<31)-1 { + // Values above the maximum flow control window size of 2^31 - 1 MUST + // be treated as a connection error (Section 5.4.1) of type + // FLOW_CONTROL_ERROR. + return nil, ConnectionError(ErrCodeFlowControl) + } + return f, nil +} + +func (f *SettingsFrame) IsAck() bool { + return f.FrameHeader.Flags.Has(FlagSettingsAck) +} + +func (f *SettingsFrame) Value(s SettingID) (v uint32, ok bool) { + f.checkValid() + buf := f.p + for len(buf) > 0 { + settingID := SettingID(binary.BigEndian.Uint16(buf[:2])) + if settingID == s { + return binary.BigEndian.Uint32(buf[2:6]), true + } + buf = buf[6:] + } + return 0, false +} + +// ForeachSetting runs fn for each setting. +// It stops and returns the first error. +func (f *SettingsFrame) ForeachSetting(fn func(Setting) error) error { + f.checkValid() + buf := f.p + for len(buf) > 0 { + if err := fn(Setting{ + SettingID(binary.BigEndian.Uint16(buf[:2])), + binary.BigEndian.Uint32(buf[2:6]), + }); err != nil { + return err + } + buf = buf[6:] + } + return nil +} + +// WriteSettings writes a SETTINGS frame with zero or more settings +// specified and the ACK bit not set. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteSettings(settings ...Setting) error { + f.startWrite(FrameSettings, 0, 0) + for _, s := range settings { + f.writeUint16(uint16(s.ID)) + f.writeUint32(s.Val) + } + return f.endWrite() +} + +// WriteSettings writes an empty SETTINGS frame with the ACK bit set. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteSettingsAck() error { + f.startWrite(FrameSettings, FlagSettingsAck, 0) + return f.endWrite() +} + +// A PingFrame is a mechanism for measuring a minimal round trip time +// from the sender, as well as determining whether an idle connection +// is still functional. +// See http://http2.github.io/http2-spec/#rfc.section.6.7 +type PingFrame struct { + FrameHeader + Data [8]byte +} + +func (f *PingFrame) IsAck() bool { return f.Flags.Has(FlagPingAck) } + +func parsePingFrame(fh FrameHeader, payload []byte) (Frame, error) { + if len(payload) != 8 { + return nil, ConnectionError(ErrCodeFrameSize) + } + if fh.StreamID != 0 { + return nil, ConnectionError(ErrCodeProtocol) + } + f := &PingFrame{FrameHeader: fh} + copy(f.Data[:], payload) + return f, nil +} + +func (f *Framer) WritePing(ack bool, data [8]byte) error { + var flags Flags + if ack { + flags = FlagPingAck + } + f.startWrite(FramePing, flags, 0) + f.writeBytes(data[:]) + return f.endWrite() +} + +// A GoAwayFrame informs the remote peer to stop creating streams on this connection. +// See http://http2.github.io/http2-spec/#rfc.section.6.8 +type GoAwayFrame struct { + FrameHeader + LastStreamID uint32 + ErrCode ErrCode + debugData []byte +} + +// DebugData returns any debug data in the GOAWAY frame. Its contents +// are not defined. +// The caller must not retain the returned memory past the next +// call to ReadFrame. +func (f *GoAwayFrame) DebugData() []byte { + f.checkValid() + return f.debugData +} + +func parseGoAwayFrame(fh FrameHeader, p []byte) (Frame, error) { + if fh.StreamID != 0 { + return nil, ConnectionError(ErrCodeProtocol) + } + if len(p) < 8 { + return nil, ConnectionError(ErrCodeFrameSize) + } + return &GoAwayFrame{ + FrameHeader: fh, + LastStreamID: binary.BigEndian.Uint32(p[:4]) & (1<<31 - 1), + ErrCode: ErrCode(binary.BigEndian.Uint32(p[4:8])), + debugData: p[8:], + }, nil +} + +func (f *Framer) WriteGoAway(maxStreamID uint32, code ErrCode, debugData []byte) error { + f.startWrite(FrameGoAway, 0, 0) + f.writeUint32(maxStreamID & (1<<31 - 1)) + f.writeUint32(uint32(code)) + f.writeBytes(debugData) + return f.endWrite() +} + +// An UnknownFrame is the frame type returned when the frame type is unknown +// or no specific frame type parser exists. +type UnknownFrame struct { + FrameHeader + p []byte +} + +// Payload returns the frame's payload (after the header). It is not +// valid to call this method after a subsequent call to +// Framer.ReadFrame, nor is it valid to retain the returned slice. +// The memory is owned by the Framer and is invalidated when the next +// frame is read. +func (f *UnknownFrame) Payload() []byte { + f.checkValid() + return f.p +} + +func parseUnknownFrame(fh FrameHeader, p []byte) (Frame, error) { + return &UnknownFrame{fh, p}, nil +} + +// A WindowUpdateFrame is used to implement flow control. +// See http://http2.github.io/http2-spec/#rfc.section.6.9 +type WindowUpdateFrame struct { + FrameHeader + Increment uint32 // never read with high bit set +} + +func parseWindowUpdateFrame(fh FrameHeader, p []byte) (Frame, error) { + if len(p) != 4 { + return nil, ConnectionError(ErrCodeFrameSize) + } + inc := binary.BigEndian.Uint32(p[:4]) & 0x7fffffff // mask off high reserved bit + if inc == 0 { + // A receiver MUST treat the receipt of a + // WINDOW_UPDATE frame with an flow control window + // increment of 0 as a stream error (Section 5.4.2) of + // type PROTOCOL_ERROR; errors on the connection flow + // control window MUST be treated as a connection + // error (Section 5.4.1). + if fh.StreamID == 0 { + return nil, ConnectionError(ErrCodeProtocol) + } + return nil, StreamError{fh.StreamID, ErrCodeProtocol} + } + return &WindowUpdateFrame{ + FrameHeader: fh, + Increment: inc, + }, nil +} + +// WriteWindowUpdate writes a WINDOW_UPDATE frame. +// The increment value must be between 1 and 2,147,483,647, inclusive. +// If the Stream ID is zero, the window update applies to the +// connection as a whole. +func (f *Framer) WriteWindowUpdate(streamID, incr uint32) error { + // "The legal range for the increment to the flow control window is 1 to 2^31-1 (2,147,483,647) octets." + if (incr < 1 || incr > 2147483647) && !f.AllowIllegalWrites { + return errors.New("illegal window increment value") + } + f.startWrite(FrameWindowUpdate, 0, streamID) + f.writeUint32(incr) + return f.endWrite() +} + +// A HeadersFrame is used to open a stream and additionally carries a +// header block fragment. +type HeadersFrame struct { + FrameHeader + + // Priority is set if FlagHeadersPriority is set in the FrameHeader. + Priority PriorityParam + + headerFragBuf []byte // not owned +} + +func (f *HeadersFrame) HeaderBlockFragment() []byte { + f.checkValid() + return f.headerFragBuf +} + +func (f *HeadersFrame) HeadersEnded() bool { + return f.FrameHeader.Flags.Has(FlagHeadersEndHeaders) +} + +func (f *HeadersFrame) StreamEnded() bool { + return f.FrameHeader.Flags.Has(FlagHeadersEndStream) +} + +func (f *HeadersFrame) HasPriority() bool { + return f.FrameHeader.Flags.Has(FlagHeadersPriority) +} + +func parseHeadersFrame(fh FrameHeader, p []byte) (_ Frame, err error) { + hf := &HeadersFrame{ + FrameHeader: fh, + } + if fh.StreamID == 0 { + // HEADERS frames MUST be associated with a stream. If a HEADERS frame + // is received whose stream identifier field is 0x0, the recipient MUST + // respond with a connection error (Section 5.4.1) of type + // PROTOCOL_ERROR. + return nil, connError{ErrCodeProtocol, "HEADERS frame with stream ID 0"} + } + var padLength uint8 + if fh.Flags.Has(FlagHeadersPadded) { + if p, padLength, err = readByte(p); err != nil { + return + } + } + if fh.Flags.Has(FlagHeadersPriority) { + var v uint32 + p, v, err = readUint32(p) + if err != nil { + return nil, err + } + hf.Priority.StreamDep = v & 0x7fffffff + hf.Priority.Exclusive = (v != hf.Priority.StreamDep) // high bit was set + p, hf.Priority.Weight, err = readByte(p) + if err != nil { + return nil, err + } + } + if len(p)-int(padLength) <= 0 { + return nil, StreamError{fh.StreamID, ErrCodeProtocol} + } + hf.headerFragBuf = p[:len(p)-int(padLength)] + return hf, nil +} + +// HeadersFrameParam are the parameters for writing a HEADERS frame. +type HeadersFrameParam struct { + // StreamID is the required Stream ID to initiate. + StreamID uint32 + // BlockFragment is part (or all) of a Header Block. + BlockFragment []byte + + // EndStream indicates that the header block is the last that + // the endpoint will send for the identified stream. Setting + // this flag causes the stream to enter one of "half closed" + // states. + EndStream bool + + // EndHeaders indicates that this frame contains an entire + // header block and is not followed by any + // CONTINUATION frames. + EndHeaders bool + + // PadLength is the optional number of bytes of zeros to add + // to this frame. + PadLength uint8 + + // Priority, if non-zero, includes stream priority information + // in the HEADER frame. + Priority PriorityParam +} + +// WriteHeaders writes a single HEADERS frame. +// +// This is a low-level header writing method. Encoding headers and +// splitting them into any necessary CONTINUATION frames is handled +// elsewhere. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteHeaders(p HeadersFrameParam) error { + if !validStreamID(p.StreamID) && !f.AllowIllegalWrites { + return errStreamID + } + var flags Flags + if p.PadLength != 0 { + flags |= FlagHeadersPadded + } + if p.EndStream { + flags |= FlagHeadersEndStream + } + if p.EndHeaders { + flags |= FlagHeadersEndHeaders + } + if !p.Priority.IsZero() { + flags |= FlagHeadersPriority + } + f.startWrite(FrameHeaders, flags, p.StreamID) + if p.PadLength != 0 { + f.writeByte(p.PadLength) + } + if !p.Priority.IsZero() { + v := p.Priority.StreamDep + if !validStreamIDOrZero(v) && !f.AllowIllegalWrites { + return errDepStreamID + } + if p.Priority.Exclusive { + v |= 1 << 31 + } + f.writeUint32(v) + f.writeByte(p.Priority.Weight) + } + f.wbuf = append(f.wbuf, p.BlockFragment...) + f.wbuf = append(f.wbuf, padZeros[:p.PadLength]...) + return f.endWrite() +} + +// A PriorityFrame specifies the sender-advised priority of a stream. +// See http://http2.github.io/http2-spec/#rfc.section.6.3 +type PriorityFrame struct { + FrameHeader + PriorityParam +} + +// PriorityParam are the stream prioritzation parameters. +type PriorityParam struct { + // StreamDep is a 31-bit stream identifier for the + // stream that this stream depends on. Zero means no + // dependency. + StreamDep uint32 + + // Exclusive is whether the dependency is exclusive. + Exclusive bool + + // Weight is the stream's zero-indexed weight. It should be + // set together with StreamDep, or neither should be set. Per + // the spec, "Add one to the value to obtain a weight between + // 1 and 256." + Weight uint8 +} + +func (p PriorityParam) IsZero() bool { + return p == PriorityParam{} +} + +func parsePriorityFrame(fh FrameHeader, payload []byte) (Frame, error) { + if fh.StreamID == 0 { + return nil, connError{ErrCodeProtocol, "PRIORITY frame with stream ID 0"} + } + if len(payload) != 5 { + return nil, connError{ErrCodeFrameSize, fmt.Sprintf("PRIORITY frame payload size was %d; want 5", len(payload))} + } + v := binary.BigEndian.Uint32(payload[:4]) + streamID := v & 0x7fffffff // mask off high bit + return &PriorityFrame{ + FrameHeader: fh, + PriorityParam: PriorityParam{ + Weight: payload[4], + StreamDep: streamID, + Exclusive: streamID != v, // was high bit set? + }, + }, nil +} + +// WritePriority writes a PRIORITY frame. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WritePriority(streamID uint32, p PriorityParam) error { + if !validStreamID(streamID) && !f.AllowIllegalWrites { + return errStreamID + } + if !validStreamIDOrZero(p.StreamDep) { + return errDepStreamID + } + f.startWrite(FramePriority, 0, streamID) + v := p.StreamDep + if p.Exclusive { + v |= 1 << 31 + } + f.writeUint32(v) + f.writeByte(p.Weight) + return f.endWrite() +} + +// A RSTStreamFrame allows for abnormal termination of a stream. +// See http://http2.github.io/http2-spec/#rfc.section.6.4 +type RSTStreamFrame struct { + FrameHeader + ErrCode ErrCode +} + +func parseRSTStreamFrame(fh FrameHeader, p []byte) (Frame, error) { + if len(p) != 4 { + return nil, ConnectionError(ErrCodeFrameSize) + } + if fh.StreamID == 0 { + return nil, ConnectionError(ErrCodeProtocol) + } + return &RSTStreamFrame{fh, ErrCode(binary.BigEndian.Uint32(p[:4]))}, nil +} + +// WriteRSTStream writes a RST_STREAM frame. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteRSTStream(streamID uint32, code ErrCode) error { + if !validStreamID(streamID) && !f.AllowIllegalWrites { + return errStreamID + } + f.startWrite(FrameRSTStream, 0, streamID) + f.writeUint32(uint32(code)) + return f.endWrite() +} + +// A ContinuationFrame is used to continue a sequence of header block fragments. +// See http://http2.github.io/http2-spec/#rfc.section.6.10 +type ContinuationFrame struct { + FrameHeader + headerFragBuf []byte +} + +func parseContinuationFrame(fh FrameHeader, p []byte) (Frame, error) { + if fh.StreamID == 0 { + return nil, connError{ErrCodeProtocol, "CONTINUATION frame with stream ID 0"} + } + return &ContinuationFrame{fh, p}, nil +} + +func (f *ContinuationFrame) HeaderBlockFragment() []byte { + f.checkValid() + return f.headerFragBuf +} + +func (f *ContinuationFrame) HeadersEnded() bool { + return f.FrameHeader.Flags.Has(FlagContinuationEndHeaders) +} + +// WriteContinuation writes a CONTINUATION frame. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WriteContinuation(streamID uint32, endHeaders bool, headerBlockFragment []byte) error { + if !validStreamID(streamID) && !f.AllowIllegalWrites { + return errStreamID + } + var flags Flags + if endHeaders { + flags |= FlagContinuationEndHeaders + } + f.startWrite(FrameContinuation, flags, streamID) + f.wbuf = append(f.wbuf, headerBlockFragment...) + return f.endWrite() +} + +// A PushPromiseFrame is used to initiate a server stream. +// See http://http2.github.io/http2-spec/#rfc.section.6.6 +type PushPromiseFrame struct { + FrameHeader + PromiseID uint32 + headerFragBuf []byte // not owned +} + +func (f *PushPromiseFrame) HeaderBlockFragment() []byte { + f.checkValid() + return f.headerFragBuf +} + +func (f *PushPromiseFrame) HeadersEnded() bool { + return f.FrameHeader.Flags.Has(FlagPushPromiseEndHeaders) +} + +func parsePushPromise(fh FrameHeader, p []byte) (_ Frame, err error) { + pp := &PushPromiseFrame{ + FrameHeader: fh, + } + if pp.StreamID == 0 { + // PUSH_PROMISE frames MUST be associated with an existing, + // peer-initiated stream. The stream identifier of a + // PUSH_PROMISE frame indicates the stream it is associated + // with. If the stream identifier field specifies the value + // 0x0, a recipient MUST respond with a connection error + // (Section 5.4.1) of type PROTOCOL_ERROR. + return nil, ConnectionError(ErrCodeProtocol) + } + // The PUSH_PROMISE frame includes optional padding. + // Padding fields and flags are identical to those defined for DATA frames + var padLength uint8 + if fh.Flags.Has(FlagPushPromisePadded) { + if p, padLength, err = readByte(p); err != nil { + return + } + } + + p, pp.PromiseID, err = readUint32(p) + if err != nil { + return + } + pp.PromiseID = pp.PromiseID & (1<<31 - 1) + + if int(padLength) > len(p) { + // like the DATA frame, error out if padding is longer than the body. + return nil, ConnectionError(ErrCodeProtocol) + } + pp.headerFragBuf = p[:len(p)-int(padLength)] + return pp, nil +} + +// PushPromiseParam are the parameters for writing a PUSH_PROMISE frame. +type PushPromiseParam struct { + // StreamID is the required Stream ID to initiate. + StreamID uint32 + + // PromiseID is the required Stream ID which this + // Push Promises + PromiseID uint32 + + // BlockFragment is part (or all) of a Header Block. + BlockFragment []byte + + // EndHeaders indicates that this frame contains an entire + // header block and is not followed by any + // CONTINUATION frames. + EndHeaders bool + + // PadLength is the optional number of bytes of zeros to add + // to this frame. + PadLength uint8 +} + +// WritePushPromise writes a single PushPromise Frame. +// +// As with Header Frames, This is the low level call for writing +// individual frames. Continuation frames are handled elsewhere. +// +// It will perform exactly one Write to the underlying Writer. +// It is the caller's responsibility to not call other Write methods concurrently. +func (f *Framer) WritePushPromise(p PushPromiseParam) error { + if !validStreamID(p.StreamID) && !f.AllowIllegalWrites { + return errStreamID + } + var flags Flags + if p.PadLength != 0 { + flags |= FlagPushPromisePadded + } + if p.EndHeaders { + flags |= FlagPushPromiseEndHeaders + } + f.startWrite(FramePushPromise, flags, p.StreamID) + if p.PadLength != 0 { + f.writeByte(p.PadLength) + } + if !validStreamID(p.PromiseID) && !f.AllowIllegalWrites { + return errStreamID + } + f.writeUint32(p.PromiseID) + f.wbuf = append(f.wbuf, p.BlockFragment...) + f.wbuf = append(f.wbuf, padZeros[:p.PadLength]...) + return f.endWrite() +} + +// WriteRawFrame writes a raw frame. This can be used to write +// extension frames unknown to this package. +func (f *Framer) WriteRawFrame(t FrameType, flags Flags, streamID uint32, payload []byte) error { + f.startWrite(t, flags, streamID) + f.writeBytes(payload) + return f.endWrite() +} + +func readByte(p []byte) (remain []byte, b byte, err error) { + if len(p) == 0 { + return nil, 0, io.ErrUnexpectedEOF + } + return p[1:], p[0], nil +} + +func readUint32(p []byte) (remain []byte, v uint32, err error) { + if len(p) < 4 { + return nil, 0, io.ErrUnexpectedEOF + } + return p[4:], binary.BigEndian.Uint32(p[:4]), nil +} + +type streamEnder interface { + StreamEnded() bool +} + +type headersEnder interface { + HeadersEnded() bool +} + +type headersOrContinuation interface { + headersEnder + HeaderBlockFragment() []byte +} + +// A MetaHeadersFrame is the representation of one HEADERS frame and +// zero or more contiguous CONTINUATION frames and the decoding of +// their HPACK-encoded contents. +// +// This type of frame does not appear on the wire and is only returned +// by the Framer when Framer.ReadMetaHeaders is set. +type MetaHeadersFrame struct { + *HeadersFrame + + // Fields are the fields contained in the HEADERS and + // CONTINUATION frames. The underlying slice is owned by the + // Framer and must not be retained after the next call to + // ReadFrame. + // + // Fields are guaranteed to be in the correct http2 order and + // not have unknown pseudo header fields or invalid header + // field names or values. Required pseudo header fields may be + // missing, however. Use the MetaHeadersFrame.Pseudo accessor + // method access pseudo headers. + Fields []hpack.HeaderField + + // Truncated is whether the max header list size limit was hit + // and Fields is incomplete. The hpack decoder state is still + // valid, however. + Truncated bool +} + +// PseudoValue returns the given pseudo header field's value. +// The provided pseudo field should not contain the leading colon. +func (mh *MetaHeadersFrame) PseudoValue(pseudo string) string { + for _, hf := range mh.Fields { + if !hf.IsPseudo() { + return "" + } + if hf.Name[1:] == pseudo { + return hf.Value + } + } + return "" +} + +// RegularFields returns the regular (non-pseudo) header fields of mh. +// The caller does not own the returned slice. +func (mh *MetaHeadersFrame) RegularFields() []hpack.HeaderField { + for i, hf := range mh.Fields { + if !hf.IsPseudo() { + return mh.Fields[i:] + } + } + return nil +} + +// PseudoFields returns the pseudo header fields of mh. +// The caller does not own the returned slice. +func (mh *MetaHeadersFrame) PseudoFields() []hpack.HeaderField { + for i, hf := range mh.Fields { + if !hf.IsPseudo() { + return mh.Fields[:i] + } + } + return mh.Fields +} + +func (mh *MetaHeadersFrame) checkPseudos() error { + var isRequest, isResponse bool + pf := mh.PseudoFields() + for i, hf := range pf { + switch hf.Name { + case ":method", ":path", ":scheme", ":authority": + isRequest = true + case ":status": + isResponse = true + default: + return pseudoHeaderError(hf.Name) + } + // Check for duplicates. + // This would be a bad algorithm, but N is 4. + // And this doesn't allocate. + for _, hf2 := range pf[:i] { + if hf.Name == hf2.Name { + return duplicatePseudoHeaderError(hf.Name) + } + } + } + if isRequest && isResponse { + return errMixPseudoHeaderTypes + } + return nil +} + +func (fr *Framer) maxHeaderStringLen() int { + v := fr.maxHeaderListSize() + if uint32(int(v)) == v { + return int(v) + } + // They had a crazy big number for MaxHeaderBytes anyway, + // so give them unlimited header lengths: + return 0 +} + +// readMetaFrame returns 0 or more CONTINUATION frames from fr and +// merge them into into the provided hf and returns a MetaHeadersFrame +// with the decoded hpack values. +func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) { + if fr.AllowIllegalReads { + return nil, errors.New("illegal use of AllowIllegalReads with ReadMetaHeaders") + } + mh := &MetaHeadersFrame{ + HeadersFrame: hf, + } + var remainSize = fr.maxHeaderListSize() + var sawRegular bool + + var invalid error // pseudo header field errors + hdec := fr.ReadMetaHeaders + hdec.SetEmitEnabled(true) + hdec.SetMaxStringLength(fr.maxHeaderStringLen()) + hdec.SetEmitFunc(func(hf hpack.HeaderField) { + if !httplex.ValidHeaderFieldValue(hf.Value) { + invalid = headerFieldValueError(hf.Value) + } + isPseudo := strings.HasPrefix(hf.Name, ":") + if isPseudo { + if sawRegular { + invalid = errPseudoAfterRegular + } + } else { + sawRegular = true + if !validWireHeaderFieldName(hf.Name) { + invalid = headerFieldNameError(hf.Name) + } + } + + if invalid != nil { + hdec.SetEmitEnabled(false) + return + } + + size := hf.Size() + if size > remainSize { + hdec.SetEmitEnabled(false) + mh.Truncated = true + return + } + remainSize -= size + + mh.Fields = append(mh.Fields, hf) + }) + // Lose reference to MetaHeadersFrame: + defer hdec.SetEmitFunc(func(hf hpack.HeaderField) {}) + + var hc headersOrContinuation = hf + for { + frag := hc.HeaderBlockFragment() + if _, err := hdec.Write(frag); err != nil { + return nil, ConnectionError(ErrCodeCompression) + } + + if hc.HeadersEnded() { + break + } + if f, err := fr.ReadFrame(); err != nil { + return nil, err + } else { + hc = f.(*ContinuationFrame) // guaranteed by checkFrameOrder + } + } + + mh.HeadersFrame.headerFragBuf = nil + mh.HeadersFrame.invalidate() + + if err := hdec.Close(); err != nil { + return nil, ConnectionError(ErrCodeCompression) + } + if invalid != nil { + fr.errDetail = invalid + return nil, StreamError{mh.StreamID, ErrCodeProtocol} + } + if err := mh.checkPseudos(); err != nil { + fr.errDetail = err + return nil, StreamError{mh.StreamID, ErrCodeProtocol} + } + return mh, nil +} + +func summarizeFrame(f Frame) string { + var buf bytes.Buffer + f.Header().writeDebug(&buf) + switch f := f.(type) { + case *SettingsFrame: + n := 0 + f.ForeachSetting(func(s Setting) error { + n++ + if n == 1 { + buf.WriteString(", settings:") + } + fmt.Fprintf(&buf, " %v=%v,", s.ID, s.Val) + return nil + }) + if n > 0 { + buf.Truncate(buf.Len() - 1) // remove trailing comma + } + case *DataFrame: + data := f.Data() + const max = 256 + if len(data) > max { + data = data[:max] + } + fmt.Fprintf(&buf, " data=%q", data) + if len(f.Data()) > max { + fmt.Fprintf(&buf, " (%d bytes omitted)", len(f.Data())-max) + } + case *WindowUpdateFrame: + if f.StreamID == 0 { + buf.WriteString(" (conn)") + } + fmt.Fprintf(&buf, " incr=%v", f.Increment) + case *PingFrame: + fmt.Fprintf(&buf, " ping=%q", f.Data[:]) + case *GoAwayFrame: + fmt.Fprintf(&buf, " LastStreamID=%v ErrCode=%v Debug=%q", + f.LastStreamID, f.ErrCode, f.debugData) + case *RSTStreamFrame: + fmt.Fprintf(&buf, " ErrCode=%v", f.ErrCode) + } + return buf.String() +} -- cgit v1.2.3