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// Copyright 2015 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.
// Transport code.
package http2
import (
"bufio"
"bytes"
"compress/gzip"
"crypto/rand"
"crypto/tls"
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"math"
"net"
"net/http"
"sort"
"strconv"
"strings"
"sync"
"time"
"golang.org/x/net/http2/hpack"
"golang.org/x/net/idna"
"golang.org/x/net/lex/httplex"
)
const (
// transportDefaultConnFlow is how many connection-level flow control
// tokens we give the server at start-up, past the default 64k.
transportDefaultConnFlow = 1 << 30
// transportDefaultStreamFlow is how many stream-level flow
// control tokens we announce to the peer, and how many bytes
// we buffer per stream.
transportDefaultStreamFlow = 4 << 20
// transportDefaultStreamMinRefresh is the minimum number of bytes we'll send
// a stream-level WINDOW_UPDATE for at a time.
transportDefaultStreamMinRefresh = 4 << 10
defaultUserAgent = "Go-http-client/2.0"
)
// Transport is an HTTP/2 Transport.
//
// A Transport internally caches connections to servers. It is safe
// for concurrent use by multiple goroutines.
type Transport struct {
// DialTLS specifies an optional dial function for creating
// TLS connections for requests.
//
// If DialTLS is nil, tls.Dial is used.
//
// If the returned net.Conn has a ConnectionState method like tls.Conn,
// it will be used to set http.Response.TLS.
DialTLS func ( network , addr string , cfg * tls . Config ) ( net . Conn , error )
// TLSClientConfig specifies the TLS configuration to use with
// tls.Client. If nil, the default configuration is used.
TLSClientConfig * tls . Config
// ConnPool optionally specifies an alternate connection pool to use.
// If nil, the default is used.
ConnPool ClientConnPool
// DisableCompression, if true, prevents the Transport from
// requesting compression with an "Accept-Encoding: gzip"
// request header when the Request contains no existing
// Accept-Encoding value. If the Transport requests gzip on
// its own and gets a gzipped response, it's transparently
// decoded in the Response.Body. However, if the user
// explicitly requested gzip it is not automatically
// uncompressed.
DisableCompression bool
// AllowHTTP, if true, permits HTTP/2 requests using the insecure,
// plain-text "http" scheme. Note that this does not enable h2c support.
AllowHTTP bool
// MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to
// send in the initial settings frame. It is how many bytes
// of response headers are allow. Unlike the http2 spec, zero here
// means to use a default limit (currently 10MB). If you actually
// want to advertise an ulimited value to the peer, Transport
// interprets the highest possible value here (0xffffffff or 1<<32-1)
// to mean no limit.
MaxHeaderListSize uint32
// t1, if non-nil, is the standard library Transport using
// this transport. Its settings are used (but not its
// RoundTrip method, etc).
t1 * http . Transport
connPoolOnce sync . Once
connPoolOrDef ClientConnPool // non-nil version of ConnPool
}
func ( t * Transport ) maxHeaderListSize ( ) uint32 {
if t . MaxHeaderListSize == 0 {
return 10 << 20
}
if t . MaxHeaderListSize == 0xffffffff {
return 0
}
return t . MaxHeaderListSize
}
func ( t * Transport ) disableCompression ( ) bool {
return t . DisableCompression || ( t . t1 != nil && t . t1 . DisableCompression )
}
var errTransportVersion = errors . New ( "http2: ConfigureTransport is only supported starting at Go 1.6" )
// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
// It requires Go 1.6 or later and returns an error if the net/http package is too old
// or if t1 has already been HTTP/2-enabled.
func ConfigureTransport ( t1 * http . Transport ) error {
_ , err := configureTransport ( t1 ) // in configure_transport.go (go1.6) or not_go16.go
return err
}
func ( t * Transport ) connPool ( ) ClientConnPool {
t . connPoolOnce . Do ( t . initConnPool )
return t . connPoolOrDef
}
func ( t * Transport ) initConnPool ( ) {
if t . ConnPool != nil {
t . connPoolOrDef = t . ConnPool
} else {
t . connPoolOrDef = & clientConnPool { t : t }
}
}
// ClientConn is the state of a single HTTP/2 client connection to an
// HTTP/2 server.
type ClientConn struct {
t * Transport
tconn net . Conn // usually *tls.Conn, except specialized impls
tlsState * tls . ConnectionState // nil only for specialized impls
singleUse bool // whether being used for a single http.Request
// readLoop goroutine fields:
readerDone chan struct { } // closed on error
readerErr error // set before readerDone is closed
idleTimeout time . Duration // or 0 for never
idleTimer * time . Timer
mu sync . Mutex // guards following
cond * sync . Cond // hold mu; broadcast on flow/closed changes
flow flow // our conn-level flow control quota (cs.flow is per stream)
inflow flow // peer's conn-level flow control
closed bool
wantSettingsAck bool // we sent a SETTINGS frame and haven't heard back
goAway * GoAwayFrame // if non-nil, the GoAwayFrame we received
goAwayDebug string // goAway frame's debug data, retained as a string
streams map [ uint32 ] * clientStream // client-initiated
nextStreamID uint32
pings map [ [ 8 ] byte ] chan struct { } // in flight ping data to notification channel
bw * bufio . Writer
br * bufio . Reader
fr * Framer
lastActive time . Time
// Settings from peer: (also guarded by mu)
maxFrameSize uint32
maxConcurrentStreams uint32
initialWindowSize uint32
hbuf bytes . Buffer // HPACK encoder writes into this
henc * hpack . Encoder
freeBuf [ ] [ ] byte
wmu sync . Mutex // held while writing; acquire AFTER mu if holding both
werr error // first write error that has occurred
}
// clientStream is the state for a single HTTP/2 stream. One of these
// is created for each Transport.RoundTrip call.
type clientStream struct {
cc * ClientConn
req * http . Request
trace * clientTrace // or nil
ID uint32
resc chan resAndError
bufPipe pipe // buffered pipe with the flow-controlled response payload
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startedWrite bool // started request body write; guarded by cc.mu
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requestedGzip bool
on100 func ( ) // optional code to run if get a 100 continue response
flow flow // guarded by cc.mu
inflow flow // guarded by cc.mu
bytesRemain int64 // -1 means unknown; owned by transportResponseBody.Read
readErr error // sticky read error; owned by transportResponseBody.Read
stopReqBody error // if non-nil, stop writing req body; guarded by cc.mu
didReset bool // whether we sent a RST_STREAM to the server; guarded by cc.mu
peerReset chan struct { } // closed on peer reset
resetErr error // populated before peerReset is closed
done chan struct { } // closed when stream remove from cc.streams map; close calls guarded by cc.mu
// owned by clientConnReadLoop:
firstByte bool // got the first response byte
pastHeaders bool // got first MetaHeadersFrame (actual headers)
pastTrailers bool // got optional second MetaHeadersFrame (trailers)
trailer http . Header // accumulated trailers
resTrailer * http . Header // client's Response.Trailer
}
// awaitRequestCancel runs in its own goroutine and waits for the user
// to cancel a RoundTrip request, its context to expire, or for the
// request to be done (any way it might be removed from the cc.streams
// map: peer reset, successful completion, TCP connection breakage,
// etc)
func ( cs * clientStream ) awaitRequestCancel ( req * http . Request ) {
ctx := reqContext ( req )
if req . Cancel == nil && ctx . Done ( ) == nil {
return
}
select {
case <- req . Cancel :
cs . cancelStream ( )
cs . bufPipe . CloseWithError ( errRequestCanceled )
case <- ctx . Done ( ) :
cs . cancelStream ( )
cs . bufPipe . CloseWithError ( ctx . Err ( ) )
case <- cs . done :
}
}
func ( cs * clientStream ) cancelStream ( ) {
cs . cc . mu . Lock ( )
didReset := cs . didReset
cs . didReset = true
cs . cc . mu . Unlock ( )
if ! didReset {
cs . cc . writeStreamReset ( cs . ID , ErrCodeCancel , nil )
}
}
// checkResetOrDone reports any error sent in a RST_STREAM frame by the
// server, or errStreamClosed if the stream is complete.
func ( cs * clientStream ) checkResetOrDone ( ) error {
select {
case <- cs . peerReset :
return cs . resetErr
case <- cs . done :
return errStreamClosed
default :
return nil
}
}
func ( cs * clientStream ) abortRequestBodyWrite ( err error ) {
if err == nil {
panic ( "nil error" )
}
cc := cs . cc
cc . mu . Lock ( )
cs . stopReqBody = err
cc . cond . Broadcast ( )
cc . mu . Unlock ( )
}
type stickyErrWriter struct {
w io . Writer
err * error
}
func ( sew stickyErrWriter ) Write ( p [ ] byte ) ( n int , err error ) {
if * sew . err != nil {
return 0 , * sew . err
}
n , err = sew . w . Write ( p )
* sew . err = err
return
}
var ErrNoCachedConn = errors . New ( "http2: no cached connection was available" )
// RoundTripOpt are options for the Transport.RoundTripOpt method.
type RoundTripOpt struct {
// OnlyCachedConn controls whether RoundTripOpt may
// create a new TCP connection. If set true and
// no cached connection is available, RoundTripOpt
// will return ErrNoCachedConn.
OnlyCachedConn bool
}
func ( t * Transport ) RoundTrip ( req * http . Request ) ( * http . Response , error ) {
return t . RoundTripOpt ( req , RoundTripOpt { } )
}
// authorityAddr returns a given authority (a host/IP, or host:port / ip:port)
// and returns a host:port. The port 443 is added if needed.
func authorityAddr ( scheme string , authority string ) ( addr string ) {
host , port , err := net . SplitHostPort ( authority )
if err != nil { // authority didn't have a port
port = "443"
if scheme == "http" {
port = "80"
}
host = authority
}
if a , err := idna . ToASCII ( host ) ; err == nil {
host = a
}
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// IPv6 address literal, without a port:
if strings . HasPrefix ( host , "[" ) && strings . HasSuffix ( host , "]" ) {
return host + ":" + port
}
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return net . JoinHostPort ( host , port )
}
// RoundTripOpt is like RoundTrip, but takes options.
func ( t * Transport ) RoundTripOpt ( req * http . Request , opt RoundTripOpt ) ( * http . Response , error ) {
if ! ( req . URL . Scheme == "https" || ( req . URL . Scheme == "http" && t . AllowHTTP ) ) {
return nil , errors . New ( "http2: unsupported scheme" )
}
addr := authorityAddr ( req . URL . Scheme , req . URL . Host )
for {
cc , err := t . connPool ( ) . GetClientConn ( req , addr )
if err != nil {
t . vlogf ( "http2: Transport failed to get client conn for %s: %v" , addr , err )
return nil , err
}
traceGotConn ( req , cc )
res , err := cc . RoundTrip ( req )
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if err != nil {
if req , err = shouldRetryRequest ( req , err ) ; err == nil {
continue
}
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}
if err != nil {
t . vlogf ( "RoundTrip failure: %v" , err )
return nil , err
}
return res , nil
}
}
// CloseIdleConnections closes any connections which were previously
// connected from previous requests but are now sitting idle.
// It does not interrupt any connections currently in use.
func ( t * Transport ) CloseIdleConnections ( ) {
if cp , ok := t . connPool ( ) . ( clientConnPoolIdleCloser ) ; ok {
cp . closeIdleConnections ( )
}
}
var (
errClientConnClosed = errors . New ( "http2: client conn is closed" )
errClientConnUnusable = errors . New ( "http2: client conn not usable" )
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errClientConnGotGoAway = errors . New ( "http2: Transport received Server's graceful shutdown GOAWAY" )
errClientConnGotGoAwayAfterSomeReqBody = errors . New ( "http2: Transport received Server's graceful shutdown GOAWAY; some request body already written" )
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)
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// shouldRetryRequest is called by RoundTrip when a request fails to get
// response headers. It is always called with a non-nil error.
// It returns either a request to retry (either the same request, or a
// modified clone), or an error if the request can't be replayed.
func shouldRetryRequest ( req * http . Request , err error ) ( * http . Request , error ) {
switch err {
default :
return nil , err
case errClientConnUnusable , errClientConnGotGoAway :
return req , nil
case errClientConnGotGoAwayAfterSomeReqBody :
// If the Body is nil (or http.NoBody), it's safe to reuse
// this request and its Body.
if req . Body == nil || reqBodyIsNoBody ( req . Body ) {
return req , nil
}
// Otherwise we depend on the Request having its GetBody
// func defined.
getBody := reqGetBody ( req ) // Go 1.8: getBody = req.GetBody
if getBody == nil {
return nil , errors . New ( "http2: Transport: peer server initiated graceful shutdown after some of Request.Body was written; define Request.GetBody to avoid this error" )
}
body , err := getBody ( )
if err != nil {
return nil , err
}
newReq := * req
newReq . Body = body
return & newReq , nil
}
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}
func ( t * Transport ) dialClientConn ( addr string , singleUse bool ) ( * ClientConn , error ) {
host , _ , err := net . SplitHostPort ( addr )
if err != nil {
return nil , err
}
tconn , err := t . dialTLS ( ) ( "tcp" , addr , t . newTLSConfig ( host ) )
if err != nil {
return nil , err
}
return t . newClientConn ( tconn , singleUse )
}
func ( t * Transport ) newTLSConfig ( host string ) * tls . Config {
cfg := new ( tls . Config )
if t . TLSClientConfig != nil {
* cfg = * cloneTLSConfig ( t . TLSClientConfig )
}
if ! strSliceContains ( cfg . NextProtos , NextProtoTLS ) {
cfg . NextProtos = append ( [ ] string { NextProtoTLS } , cfg . NextProtos ... )
}
if cfg . ServerName == "" {
cfg . ServerName = host
}
return cfg
}
func ( t * Transport ) dialTLS ( ) func ( string , string , * tls . Config ) ( net . Conn , error ) {
if t . DialTLS != nil {
return t . DialTLS
}
return t . dialTLSDefault
}
func ( t * Transport ) dialTLSDefault ( network , addr string , cfg * tls . Config ) ( net . Conn , error ) {
cn , err := tls . Dial ( network , addr , cfg )
if err != nil {
return nil , err
}
if err := cn . Handshake ( ) ; err != nil {
return nil , err
}
if ! cfg . InsecureSkipVerify {
if err := cn . VerifyHostname ( cfg . ServerName ) ; err != nil {
return nil , err
}
}
state := cn . ConnectionState ( )
if p := state . NegotiatedProtocol ; p != NextProtoTLS {
return nil , fmt . Errorf ( "http2: unexpected ALPN protocol %q; want %q" , p , NextProtoTLS )
}
if ! state . NegotiatedProtocolIsMutual {
return nil , errors . New ( "http2: could not negotiate protocol mutually" )
}
return cn , nil
}
// disableKeepAlives reports whether connections should be closed as
// soon as possible after handling the first request.
func ( t * Transport ) disableKeepAlives ( ) bool {
return t . t1 != nil && t . t1 . DisableKeepAlives
}
func ( t * Transport ) expectContinueTimeout ( ) time . Duration {
if t . t1 == nil {
return 0
}
return transportExpectContinueTimeout ( t . t1 )
}
func ( t * Transport ) NewClientConn ( c net . Conn ) ( * ClientConn , error ) {
return t . newClientConn ( c , false )
}
func ( t * Transport ) newClientConn ( c net . Conn , singleUse bool ) ( * ClientConn , error ) {
cc := & ClientConn {
t : t ,
tconn : c ,
readerDone : make ( chan struct { } ) ,
nextStreamID : 1 ,
maxFrameSize : 16 << 10 , // spec default
initialWindowSize : 65535 , // spec default
maxConcurrentStreams : 1000 , // "infinite", per spec. 1000 seems good enough.
streams : make ( map [ uint32 ] * clientStream ) ,
singleUse : singleUse ,
wantSettingsAck : true ,
pings : make ( map [ [ 8 ] byte ] chan struct { } ) ,
}
if d := t . idleConnTimeout ( ) ; d != 0 {
cc . idleTimeout = d
cc . idleTimer = time . AfterFunc ( d , cc . onIdleTimeout )
}
if VerboseLogs {
t . vlogf ( "http2: Transport creating client conn %p to %v" , cc , c . RemoteAddr ( ) )
}
cc . cond = sync . NewCond ( & cc . mu )
cc . flow . add ( int32 ( initialWindowSize ) )
// TODO: adjust this writer size to account for frame size +
// MTU + crypto/tls record padding.
cc . bw = bufio . NewWriter ( stickyErrWriter { c , & cc . werr } )
cc . br = bufio . NewReader ( c )
cc . fr = NewFramer ( cc . bw , cc . br )
cc . fr . ReadMetaHeaders = hpack . NewDecoder ( initialHeaderTableSize , nil )
cc . fr . MaxHeaderListSize = t . maxHeaderListSize ( )
// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
// henc in response to SETTINGS frames?
cc . henc = hpack . NewEncoder ( & cc . hbuf )
if cs , ok := c . ( connectionStater ) ; ok {
state := cs . ConnectionState ( )
cc . tlsState = & state
}
initialSettings := [ ] Setting {
{ ID : SettingEnablePush , Val : 0 } ,
{ ID : SettingInitialWindowSize , Val : transportDefaultStreamFlow } ,
}
if max := t . maxHeaderListSize ( ) ; max != 0 {
initialSettings = append ( initialSettings , Setting { ID : SettingMaxHeaderListSize , Val : max } )
}
cc . bw . Write ( clientPreface )
cc . fr . WriteSettings ( initialSettings ... )
cc . fr . WriteWindowUpdate ( 0 , transportDefaultConnFlow )
cc . inflow . add ( transportDefaultConnFlow + initialWindowSize )
cc . bw . Flush ( )
if cc . werr != nil {
return nil , cc . werr
}
go cc . readLoop ( )
return cc , nil
}
func ( cc * ClientConn ) setGoAway ( f * GoAwayFrame ) {
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
old := cc . goAway
cc . goAway = f
// Merge the previous and current GoAway error frames.
if cc . goAwayDebug == "" {
cc . goAwayDebug = string ( f . DebugData ( ) )
}
if old != nil && old . ErrCode != ErrCodeNo {
cc . goAway . ErrCode = old . ErrCode
}
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last := f . LastStreamID
for streamID , cs := range cc . streams {
if streamID > last {
select {
case cs . resc <- resAndError { err : errClientConnGotGoAway } :
default :
}
}
}
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}
func ( cc * ClientConn ) CanTakeNewRequest ( ) bool {
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
return cc . canTakeNewRequestLocked ( )
}
func ( cc * ClientConn ) canTakeNewRequestLocked ( ) bool {
if cc . singleUse && cc . nextStreamID > 1 {
return false
}
return cc . goAway == nil && ! cc . closed &&
int64 ( len ( cc . streams ) + 1 ) < int64 ( cc . maxConcurrentStreams ) &&
cc . nextStreamID < math . MaxInt32
}
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// onIdleTimeout is called from a time.AfterFunc goroutine. It will
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// only be called when we're idle, but because we're coming from a new
// goroutine, there could be a new request coming in at the same time,
// so this simply calls the synchronized closeIfIdle to shut down this
// connection. The timer could just call closeIfIdle, but this is more
// clear.
func ( cc * ClientConn ) onIdleTimeout ( ) {
cc . closeIfIdle ( )
}
func ( cc * ClientConn ) closeIfIdle ( ) {
cc . mu . Lock ( )
if len ( cc . streams ) > 0 {
cc . mu . Unlock ( )
return
}
cc . closed = true
nextID := cc . nextStreamID
// TODO: do clients send GOAWAY too? maybe? Just Close:
cc . mu . Unlock ( )
if VerboseLogs {
cc . vlogf ( "http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)" , cc , cc . singleUse , nextID - 2 )
}
cc . tconn . Close ( )
}
const maxAllocFrameSize = 512 << 10
// frameBuffer returns a scratch buffer suitable for writing DATA frames.
// They're capped at the min of the peer's max frame size or 512KB
// (kinda arbitrarily), but definitely capped so we don't allocate 4GB
// bufers.
func ( cc * ClientConn ) frameScratchBuffer ( ) [ ] byte {
cc . mu . Lock ( )
size := cc . maxFrameSize
if size > maxAllocFrameSize {
size = maxAllocFrameSize
}
for i , buf := range cc . freeBuf {
if len ( buf ) >= int ( size ) {
cc . freeBuf [ i ] = nil
cc . mu . Unlock ( )
return buf [ : size ]
}
}
cc . mu . Unlock ( )
return make ( [ ] byte , size )
}
func ( cc * ClientConn ) putFrameScratchBuffer ( buf [ ] byte ) {
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
const maxBufs = 4 // arbitrary; 4 concurrent requests per conn? investigate.
if len ( cc . freeBuf ) < maxBufs {
cc . freeBuf = append ( cc . freeBuf , buf )
return
}
for i , old := range cc . freeBuf {
if old == nil {
cc . freeBuf [ i ] = buf
return
}
}
// forget about it.
}
// errRequestCanceled is a copy of net/http's errRequestCanceled because it's not
// exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests.
var errRequestCanceled = errors . New ( "net/http: request canceled" )
func commaSeparatedTrailers ( req * http . Request ) ( string , error ) {
keys := make ( [ ] string , 0 , len ( req . Trailer ) )
for k := range req . Trailer {
k = http . CanonicalHeaderKey ( k )
switch k {
case "Transfer-Encoding" , "Trailer" , "Content-Length" :
return "" , & badStringError { "invalid Trailer key" , k }
}
keys = append ( keys , k )
}
if len ( keys ) > 0 {
sort . Strings ( keys )
return strings . Join ( keys , "," ) , nil
}
return "" , nil
}
func ( cc * ClientConn ) responseHeaderTimeout ( ) time . Duration {
if cc . t . t1 != nil {
return cc . t . t1 . ResponseHeaderTimeout
}
// No way to do this (yet?) with just an http2.Transport. Probably
// no need. Request.Cancel this is the new way. We only need to support
// this for compatibility with the old http.Transport fields when
// we're doing transparent http2.
return 0
}
// checkConnHeaders checks whether req has any invalid connection-level headers.
// per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields.
// Certain headers are special-cased as okay but not transmitted later.
func checkConnHeaders ( req * http . Request ) error {
if v := req . Header . Get ( "Upgrade" ) ; v != "" {
return fmt . Errorf ( "http2: invalid Upgrade request header: %q" , req . Header [ "Upgrade" ] )
}
if vv := req . Header [ "Transfer-Encoding" ] ; len ( vv ) > 0 && ( len ( vv ) > 1 || vv [ 0 ] != "" && vv [ 0 ] != "chunked" ) {
return fmt . Errorf ( "http2: invalid Transfer-Encoding request header: %q" , vv )
}
if vv := req . Header [ "Connection" ] ; len ( vv ) > 0 && ( len ( vv ) > 1 || vv [ 0 ] != "" && vv [ 0 ] != "close" && vv [ 0 ] != "keep-alive" ) {
return fmt . Errorf ( "http2: invalid Connection request header: %q" , vv )
}
return nil
}
// actualContentLength returns a sanitized version of
// req.ContentLength, where 0 actually means zero (not unknown) and -1
// means unknown.
func actualContentLength ( req * http . Request ) int64 {
if req . Body == nil {
return 0
}
if req . ContentLength != 0 {
return req . ContentLength
}
return - 1
}
func ( cc * ClientConn ) RoundTrip ( req * http . Request ) ( * http . Response , error ) {
if err := checkConnHeaders ( req ) ; err != nil {
return nil , err
}
if cc . idleTimer != nil {
cc . idleTimer . Stop ( )
}
trailers , err := commaSeparatedTrailers ( req )
if err != nil {
return nil , err
}
hasTrailers := trailers != ""
cc . mu . Lock ( )
cc . lastActive = time . Now ( )
if cc . closed || ! cc . canTakeNewRequestLocked ( ) {
cc . mu . Unlock ( )
return nil , errClientConnUnusable
}
body := req . Body
hasBody := body != nil
contentLen := actualContentLength ( req )
// TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere?
var requestedGzip bool
if ! cc . t . disableCompression ( ) &&
req . Header . Get ( "Accept-Encoding" ) == "" &&
req . Header . Get ( "Range" ) == "" &&
req . Method != "HEAD" {
// Request gzip only, not deflate. Deflate is ambiguous and
// not as universally supported anyway.
// See: http://www.gzip.org/zlib/zlib_faq.html#faq38
//
// Note that we don't request this for HEAD requests,
// due to a bug in nginx:
// http://trac.nginx.org/nginx/ticket/358
// https://golang.org/issue/5522
//
// We don't request gzip if the request is for a range, since
// auto-decoding a portion of a gzipped document will just fail
// anyway. See https://golang.org/issue/8923
requestedGzip = true
}
// we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is
// sent by writeRequestBody below, along with any Trailers,
// again in form HEADERS{1}, CONTINUATION{0,})
hdrs , err := cc . encodeHeaders ( req , requestedGzip , trailers , contentLen )
if err != nil {
cc . mu . Unlock ( )
return nil , err
}
cs := cc . newStream ( )
cs . req = req
cs . trace = requestTrace ( req )
cs . requestedGzip = requestedGzip
bodyWriter := cc . t . getBodyWriterState ( cs , body )
cs . on100 = bodyWriter . on100
cc . wmu . Lock ( )
endStream := ! hasBody && ! hasTrailers
werr := cc . writeHeaders ( cs . ID , endStream , hdrs )
cc . wmu . Unlock ( )
traceWroteHeaders ( cs . trace )
cc . mu . Unlock ( )
if werr != nil {
if hasBody {
req . Body . Close ( ) // per RoundTripper contract
bodyWriter . cancel ( )
}
cc . forgetStreamID ( cs . ID )
// Don't bother sending a RST_STREAM (our write already failed;
// no need to keep writing)
traceWroteRequest ( cs . trace , werr )
return nil , werr
}
var respHeaderTimer <- chan time . Time
if hasBody {
bodyWriter . scheduleBodyWrite ( )
} else {
traceWroteRequest ( cs . trace , nil )
if d := cc . responseHeaderTimeout ( ) ; d != 0 {
timer := time . NewTimer ( d )
defer timer . Stop ( )
respHeaderTimer = timer . C
}
}
readLoopResCh := cs . resc
bodyWritten := false
ctx := reqContext ( req )
handleReadLoopResponse := func ( re resAndError ) ( * http . Response , error ) {
res := re . res
if re . err != nil || res . StatusCode > 299 {
// On error or status code 3xx, 4xx, 5xx, etc abort any
// ongoing write, assuming that the server doesn't care
// about our request body. If the server replied with 1xx or
// 2xx, however, then assume the server DOES potentially
// want our body (e.g. full-duplex streaming:
// golang.org/issue/13444). If it turns out the server
2017-02-17 17:49:51 +01:00
// doesn't, they'll RST_STREAM us soon enough. This is a
// heuristic to avoid adding knobs to Transport. Hopefully
2016-11-19 11:03:41 +01:00
// we can keep it.
bodyWriter . cancel ( )
cs . abortRequestBodyWrite ( errStopReqBodyWrite )
}
if re . err != nil {
2017-01-02 17:12:05 +01:00
if re . err == errClientConnGotGoAway {
cc . mu . Lock ( )
if cs . startedWrite {
re . err = errClientConnGotGoAwayAfterSomeReqBody
}
cc . mu . Unlock ( )
}
2016-11-19 11:03:41 +01:00
cc . forgetStreamID ( cs . ID )
return nil , re . err
}
res . Request = req
res . TLS = cc . tlsState
return res , nil
}
for {
select {
case re := <- readLoopResCh :
return handleReadLoopResponse ( re )
case <- respHeaderTimer :
cc . forgetStreamID ( cs . ID )
if ! hasBody || bodyWritten {
cc . writeStreamReset ( cs . ID , ErrCodeCancel , nil )
} else {
bodyWriter . cancel ( )
cs . abortRequestBodyWrite ( errStopReqBodyWriteAndCancel )
}
return nil , errTimeout
case <- ctx . Done ( ) :
cc . forgetStreamID ( cs . ID )
if ! hasBody || bodyWritten {
cc . writeStreamReset ( cs . ID , ErrCodeCancel , nil )
} else {
bodyWriter . cancel ( )
cs . abortRequestBodyWrite ( errStopReqBodyWriteAndCancel )
}
return nil , ctx . Err ( )
case <- req . Cancel :
cc . forgetStreamID ( cs . ID )
if ! hasBody || bodyWritten {
cc . writeStreamReset ( cs . ID , ErrCodeCancel , nil )
} else {
bodyWriter . cancel ( )
cs . abortRequestBodyWrite ( errStopReqBodyWriteAndCancel )
}
return nil , errRequestCanceled
case <- cs . peerReset :
// processResetStream already removed the
// stream from the streams map; no need for
// forgetStreamID.
return nil , cs . resetErr
case err := <- bodyWriter . resc :
// Prefer the read loop's response, if available. Issue 16102.
select {
case re := <- readLoopResCh :
return handleReadLoopResponse ( re )
default :
}
if err != nil {
return nil , err
}
bodyWritten = true
if d := cc . responseHeaderTimeout ( ) ; d != 0 {
timer := time . NewTimer ( d )
defer timer . Stop ( )
respHeaderTimer = timer . C
}
}
}
}
// requires cc.wmu be held
func ( cc * ClientConn ) writeHeaders ( streamID uint32 , endStream bool , hdrs [ ] byte ) error {
first := true // first frame written (HEADERS is first, then CONTINUATION)
frameSize := int ( cc . maxFrameSize )
for len ( hdrs ) > 0 && cc . werr == nil {
chunk := hdrs
if len ( chunk ) > frameSize {
chunk = chunk [ : frameSize ]
}
hdrs = hdrs [ len ( chunk ) : ]
endHeaders := len ( hdrs ) == 0
if first {
cc . fr . WriteHeaders ( HeadersFrameParam {
StreamID : streamID ,
BlockFragment : chunk ,
EndStream : endStream ,
EndHeaders : endHeaders ,
} )
first = false
} else {
cc . fr . WriteContinuation ( streamID , endHeaders , chunk )
}
}
// TODO(bradfitz): this Flush could potentially block (as
// could the WriteHeaders call(s) above), which means they
// wouldn't respond to Request.Cancel being readable. That's
// rare, but this should probably be in a goroutine.
cc . bw . Flush ( )
return cc . werr
}
// internal error values; they don't escape to callers
var (
// abort request body write; don't send cancel
errStopReqBodyWrite = errors . New ( "http2: aborting request body write" )
// abort request body write, but send stream reset of cancel.
errStopReqBodyWriteAndCancel = errors . New ( "http2: canceling request" )
)
func ( cs * clientStream ) writeRequestBody ( body io . Reader , bodyCloser io . Closer ) ( err error ) {
cc := cs . cc
sentEnd := false // whether we sent the final DATA frame w/ END_STREAM
buf := cc . frameScratchBuffer ( )
defer cc . putFrameScratchBuffer ( buf )
defer func ( ) {
traceWroteRequest ( cs . trace , err )
// TODO: write h12Compare test showing whether
// Request.Body is closed by the Transport,
// and in multiple cases: server replies <=299 and >299
// while still writing request body
cerr := bodyCloser . Close ( )
if err == nil {
err = cerr
}
} ( )
req := cs . req
hasTrailers := req . Trailer != nil
var sawEOF bool
for ! sawEOF {
n , err := body . Read ( buf )
if err == io . EOF {
sawEOF = true
err = nil
} else if err != nil {
return err
}
remain := buf [ : n ]
for len ( remain ) > 0 && err == nil {
var allowed int32
allowed , err = cs . awaitFlowControl ( len ( remain ) )
switch {
case err == errStopReqBodyWrite :
return err
case err == errStopReqBodyWriteAndCancel :
cc . writeStreamReset ( cs . ID , ErrCodeCancel , nil )
return err
case err != nil :
return err
}
cc . wmu . Lock ( )
data := remain [ : allowed ]
remain = remain [ allowed : ]
sentEnd = sawEOF && len ( remain ) == 0 && ! hasTrailers
err = cc . fr . WriteData ( cs . ID , sentEnd , data )
if err == nil {
// TODO(bradfitz): this flush is for latency, not bandwidth.
// Most requests won't need this. Make this opt-in or
// opt-out? Use some heuristic on the body type? Nagel-like
// timers? Based on 'n'? Only last chunk of this for loop,
// unless flow control tokens are low? For now, always.
// If we change this, see comment below.
err = cc . bw . Flush ( )
}
cc . wmu . Unlock ( )
}
if err != nil {
return err
}
}
if sentEnd {
// Already sent END_STREAM (which implies we have no
// trailers) and flushed, because currently all
// WriteData frames above get a flush. So we're done.
return nil
}
var trls [ ] byte
if hasTrailers {
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
trls = cc . encodeTrailers ( req )
}
cc . wmu . Lock ( )
defer cc . wmu . Unlock ( )
// Two ways to send END_STREAM: either with trailers, or
// with an empty DATA frame.
if len ( trls ) > 0 {
err = cc . writeHeaders ( cs . ID , true , trls )
} else {
err = cc . fr . WriteData ( cs . ID , true , nil )
}
if ferr := cc . bw . Flush ( ) ; ferr != nil && err == nil {
err = ferr
}
return err
}
// awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow
// control tokens from the server.
// It returns either the non-zero number of tokens taken or an error
// if the stream is dead.
func ( cs * clientStream ) awaitFlowControl ( maxBytes int ) ( taken int32 , err error ) {
cc := cs . cc
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
for {
if cc . closed {
return 0 , errClientConnClosed
}
if cs . stopReqBody != nil {
return 0 , cs . stopReqBody
}
if err := cs . checkResetOrDone ( ) ; err != nil {
return 0 , err
}
if a := cs . flow . available ( ) ; a > 0 {
take := a
if int ( take ) > maxBytes {
take = int32 ( maxBytes ) // can't truncate int; take is int32
}
if take > int32 ( cc . maxFrameSize ) {
take = int32 ( cc . maxFrameSize )
}
cs . flow . take ( take )
return take , nil
}
cc . cond . Wait ( )
}
}
type badStringError struct {
what string
str string
}
func ( e * badStringError ) Error ( ) string { return fmt . Sprintf ( "%s %q" , e . what , e . str ) }
// requires cc.mu be held.
func ( cc * ClientConn ) encodeHeaders ( req * http . Request , addGzipHeader bool , trailers string , contentLength int64 ) ( [ ] byte , error ) {
cc . hbuf . Reset ( )
host := req . Host
if host == "" {
host = req . URL . Host
}
host , err := httplex . PunycodeHostPort ( host )
if err != nil {
return nil , err
}
var path string
if req . Method != "CONNECT" {
path = req . URL . RequestURI ( )
if ! validPseudoPath ( path ) {
orig := path
path = strings . TrimPrefix ( path , req . URL . Scheme + "://" + host )
if ! validPseudoPath ( path ) {
if req . URL . Opaque != "" {
return nil , fmt . Errorf ( "invalid request :path %q from URL.Opaque = %q" , orig , req . URL . Opaque )
} else {
return nil , fmt . Errorf ( "invalid request :path %q" , orig )
}
}
}
}
// Check for any invalid headers and return an error before we
// potentially pollute our hpack state. (We want to be able to
// continue to reuse the hpack encoder for future requests)
for k , vv := range req . Header {
if ! httplex . ValidHeaderFieldName ( k ) {
return nil , fmt . Errorf ( "invalid HTTP header name %q" , k )
}
for _ , v := range vv {
if ! httplex . ValidHeaderFieldValue ( v ) {
return nil , fmt . Errorf ( "invalid HTTP header value %q for header %q" , v , k )
}
}
}
// 8.1.2.3 Request Pseudo-Header Fields
// The :path pseudo-header field includes the path and query parts of the
// target URI (the path-absolute production and optionally a '?' character
// followed by the query production (see Sections 3.3 and 3.4 of
// [RFC3986]).
cc . writeHeader ( ":authority" , host )
cc . writeHeader ( ":method" , req . Method )
if req . Method != "CONNECT" {
cc . writeHeader ( ":path" , path )
cc . writeHeader ( ":scheme" , req . URL . Scheme )
}
if trailers != "" {
cc . writeHeader ( "trailer" , trailers )
}
var didUA bool
for k , vv := range req . Header {
lowKey := strings . ToLower ( k )
switch lowKey {
case "host" , "content-length" :
// Host is :authority, already sent.
// Content-Length is automatic, set below.
continue
case "connection" , "proxy-connection" , "transfer-encoding" , "upgrade" , "keep-alive" :
// Per 8.1.2.2 Connection-Specific Header
// Fields, don't send connection-specific
// fields. We have already checked if any
// are error-worthy so just ignore the rest.
continue
case "user-agent" :
// Match Go's http1 behavior: at most one
// User-Agent. If set to nil or empty string,
// then omit it. Otherwise if not mentioned,
// include the default (below).
didUA = true
if len ( vv ) < 1 {
continue
}
vv = vv [ : 1 ]
if vv [ 0 ] == "" {
continue
}
}
for _ , v := range vv {
cc . writeHeader ( lowKey , v )
}
}
if shouldSendReqContentLength ( req . Method , contentLength ) {
cc . writeHeader ( "content-length" , strconv . FormatInt ( contentLength , 10 ) )
}
if addGzipHeader {
cc . writeHeader ( "accept-encoding" , "gzip" )
}
if ! didUA {
cc . writeHeader ( "user-agent" , defaultUserAgent )
}
return cc . hbuf . Bytes ( ) , nil
}
// shouldSendReqContentLength reports whether the http2.Transport should send
// a "content-length" request header. This logic is basically a copy of the net/http
// transferWriter.shouldSendContentLength.
// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown).
// -1 means unknown.
func shouldSendReqContentLength ( method string , contentLength int64 ) bool {
if contentLength > 0 {
return true
}
if contentLength < 0 {
return false
}
// For zero bodies, whether we send a content-length depends on the method.
// It also kinda doesn't matter for http2 either way, with END_STREAM.
switch method {
case "POST" , "PUT" , "PATCH" :
return true
default :
return false
}
}
// requires cc.mu be held.
func ( cc * ClientConn ) encodeTrailers ( req * http . Request ) [ ] byte {
cc . hbuf . Reset ( )
for k , vv := range req . Trailer {
// Transfer-Encoding, etc.. have already been filter at the
// start of RoundTrip
lowKey := strings . ToLower ( k )
for _ , v := range vv {
cc . writeHeader ( lowKey , v )
}
}
return cc . hbuf . Bytes ( )
}
func ( cc * ClientConn ) writeHeader ( name , value string ) {
if VerboseLogs {
log . Printf ( "http2: Transport encoding header %q = %q" , name , value )
}
cc . henc . WriteField ( hpack . HeaderField { Name : name , Value : value } )
}
type resAndError struct {
res * http . Response
err error
}
// requires cc.mu be held.
func ( cc * ClientConn ) newStream ( ) * clientStream {
cs := & clientStream {
cc : cc ,
ID : cc . nextStreamID ,
resc : make ( chan resAndError , 1 ) ,
peerReset : make ( chan struct { } ) ,
done : make ( chan struct { } ) ,
}
cs . flow . add ( int32 ( cc . initialWindowSize ) )
cs . flow . setConnFlow ( & cc . flow )
cs . inflow . add ( transportDefaultStreamFlow )
cs . inflow . setConnFlow ( & cc . inflow )
cc . nextStreamID += 2
cc . streams [ cs . ID ] = cs
return cs
}
func ( cc * ClientConn ) forgetStreamID ( id uint32 ) {
cc . streamByID ( id , true )
}
func ( cc * ClientConn ) streamByID ( id uint32 , andRemove bool ) * clientStream {
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
cs := cc . streams [ id ]
if andRemove && cs != nil && ! cc . closed {
cc . lastActive = time . Now ( )
delete ( cc . streams , id )
if len ( cc . streams ) == 0 && cc . idleTimer != nil {
cc . idleTimer . Reset ( cc . idleTimeout )
}
close ( cs . done )
cc . cond . Broadcast ( ) // wake up checkResetOrDone via clientStream.awaitFlowControl
}
return cs
}
// clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop.
type clientConnReadLoop struct {
cc * ClientConn
activeRes map [ uint32 ] * clientStream // keyed by streamID
closeWhenIdle bool
}
// readLoop runs in its own goroutine and reads and dispatches frames.
func ( cc * ClientConn ) readLoop ( ) {
rl := & clientConnReadLoop {
cc : cc ,
activeRes : make ( map [ uint32 ] * clientStream ) ,
}
defer rl . cleanup ( )
cc . readerErr = rl . run ( )
if ce , ok := cc . readerErr . ( ConnectionError ) ; ok {
cc . wmu . Lock ( )
cc . fr . WriteGoAway ( 0 , ErrCode ( ce ) , nil )
cc . wmu . Unlock ( )
}
}
// GoAwayError is returned by the Transport when the server closes the
// TCP connection after sending a GOAWAY frame.
type GoAwayError struct {
LastStreamID uint32
ErrCode ErrCode
DebugData string
}
func ( e GoAwayError ) Error ( ) string {
return fmt . Sprintf ( "http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q" ,
e . LastStreamID , e . ErrCode , e . DebugData )
}
func isEOFOrNetReadError ( err error ) bool {
if err == io . EOF {
return true
}
ne , ok := err . ( * net . OpError )
return ok && ne . Op == "read"
}
func ( rl * clientConnReadLoop ) cleanup ( ) {
cc := rl . cc
defer cc . tconn . Close ( )
defer cc . t . connPool ( ) . MarkDead ( cc )
defer close ( cc . readerDone )
if cc . idleTimer != nil {
cc . idleTimer . Stop ( )
}
// Close any response bodies if the server closes prematurely.
// TODO: also do this if we've written the headers but not
// gotten a response yet.
err := cc . readerErr
cc . mu . Lock ( )
if cc . goAway != nil && isEOFOrNetReadError ( err ) {
err = GoAwayError {
LastStreamID : cc . goAway . LastStreamID ,
ErrCode : cc . goAway . ErrCode ,
DebugData : cc . goAwayDebug ,
}
} else if err == io . EOF {
err = io . ErrUnexpectedEOF
}
for _ , cs := range rl . activeRes {
cs . bufPipe . CloseWithError ( err )
}
for _ , cs := range cc . streams {
select {
case cs . resc <- resAndError { err : err } :
default :
}
close ( cs . done )
}
cc . closed = true
cc . cond . Broadcast ( )
cc . mu . Unlock ( )
}
func ( rl * clientConnReadLoop ) run ( ) error {
cc := rl . cc
rl . closeWhenIdle = cc . t . disableKeepAlives ( ) || cc . singleUse
gotReply := false // ever saw a HEADERS reply
gotSettings := false
for {
f , err := cc . fr . ReadFrame ( )
if err != nil {
cc . vlogf ( "http2: Transport readFrame error on conn %p: (%T) %v" , cc , err , err )
}
if se , ok := err . ( StreamError ) ; ok {
if cs := cc . streamByID ( se . StreamID , true /*ended; remove it*/ ) ; cs != nil {
cs . cc . writeStreamReset ( cs . ID , se . Code , err )
if se . Cause == nil {
se . Cause = cc . fr . errDetail
}
rl . endStreamError ( cs , se )
}
continue
} else if err != nil {
return err
}
if VerboseLogs {
cc . vlogf ( "http2: Transport received %s" , summarizeFrame ( f ) )
}
if ! gotSettings {
if _ , ok := f . ( * SettingsFrame ) ; ! ok {
cc . logf ( "protocol error: received %T before a SETTINGS frame" , f )
return ConnectionError ( ErrCodeProtocol )
}
gotSettings = true
}
maybeIdle := false // whether frame might transition us to idle
switch f := f . ( type ) {
case * MetaHeadersFrame :
err = rl . processHeaders ( f )
maybeIdle = true
gotReply = true
case * DataFrame :
err = rl . processData ( f )
maybeIdle = true
case * GoAwayFrame :
err = rl . processGoAway ( f )
maybeIdle = true
case * RSTStreamFrame :
err = rl . processResetStream ( f )
maybeIdle = true
case * SettingsFrame :
err = rl . processSettings ( f )
case * PushPromiseFrame :
err = rl . processPushPromise ( f )
case * WindowUpdateFrame :
err = rl . processWindowUpdate ( f )
case * PingFrame :
err = rl . processPing ( f )
default :
cc . logf ( "Transport: unhandled response frame type %T" , f )
}
if err != nil {
if VerboseLogs {
cc . vlogf ( "http2: Transport conn %p received error from processing frame %v: %v" , cc , summarizeFrame ( f ) , err )
}
return err
}
if rl . closeWhenIdle && gotReply && maybeIdle && len ( rl . activeRes ) == 0 {
cc . closeIfIdle ( )
}
}
}
func ( rl * clientConnReadLoop ) processHeaders ( f * MetaHeadersFrame ) error {
cc := rl . cc
cs := cc . streamByID ( f . StreamID , f . StreamEnded ( ) )
if cs == nil {
// We'd get here if we canceled a request while the
// server had its response still in flight. So if this
// was just something we canceled, ignore it.
return nil
}
if ! cs . firstByte {
if cs . trace != nil {
// TODO(bradfitz): move first response byte earlier,
// when we first read the 9 byte header, not waiting
// until all the HEADERS+CONTINUATION frames have been
// merged. This works for now.
traceFirstResponseByte ( cs . trace )
}
cs . firstByte = true
}
if ! cs . pastHeaders {
cs . pastHeaders = true
} else {
return rl . processTrailers ( cs , f )
}
res , err := rl . handleResponse ( cs , f )
if err != nil {
if _ , ok := err . ( ConnectionError ) ; ok {
return err
}
// Any other error type is a stream error.
cs . cc . writeStreamReset ( f . StreamID , ErrCodeProtocol , err )
cs . resc <- resAndError { err : err }
return nil // return nil from process* funcs to keep conn alive
}
if res == nil {
// (nil, nil) special case. See handleResponse docs.
return nil
}
if res . Body != noBody {
rl . activeRes [ cs . ID ] = cs
}
cs . resTrailer = & res . Trailer
cs . resc <- resAndError { res : res }
return nil
}
// may return error types nil, or ConnectionError. Any other error value
// is a StreamError of type ErrCodeProtocol. The returned error in that case
// is the detail.
//
// As a special case, handleResponse may return (nil, nil) to skip the
// frame (currently only used for 100 expect continue). This special
// case is going away after Issue 13851 is fixed.
func ( rl * clientConnReadLoop ) handleResponse ( cs * clientStream , f * MetaHeadersFrame ) ( * http . Response , error ) {
if f . Truncated {
return nil , errResponseHeaderListSize
}
status := f . PseudoValue ( "status" )
if status == "" {
return nil , errors . New ( "missing status pseudo header" )
}
statusCode , err := strconv . Atoi ( status )
if err != nil {
return nil , errors . New ( "malformed non-numeric status pseudo header" )
}
if statusCode == 100 {
traceGot100Continue ( cs . trace )
if cs . on100 != nil {
cs . on100 ( ) // forces any write delay timer to fire
}
cs . pastHeaders = false // do it all again
return nil , nil
}
header := make ( http . Header )
res := & http . Response {
Proto : "HTTP/2.0" ,
ProtoMajor : 2 ,
Header : header ,
StatusCode : statusCode ,
Status : status + " " + http . StatusText ( statusCode ) ,
}
for _ , hf := range f . RegularFields ( ) {
key := http . CanonicalHeaderKey ( hf . Name )
if key == "Trailer" {
t := res . Trailer
if t == nil {
t = make ( http . Header )
res . Trailer = t
}
foreachHeaderElement ( hf . Value , func ( v string ) {
t [ http . CanonicalHeaderKey ( v ) ] = nil
} )
} else {
header [ key ] = append ( header [ key ] , hf . Value )
}
}
streamEnded := f . StreamEnded ( )
isHead := cs . req . Method == "HEAD"
if ! streamEnded || isHead {
res . ContentLength = - 1
if clens := res . Header [ "Content-Length" ] ; len ( clens ) == 1 {
if clen64 , err := strconv . ParseInt ( clens [ 0 ] , 10 , 64 ) ; err == nil {
res . ContentLength = clen64
} else {
// TODO: care? unlike http/1, it won't mess up our framing, so it's
// more safe smuggling-wise to ignore.
}
} else if len ( clens ) > 1 {
// TODO: care? unlike http/1, it won't mess up our framing, so it's
// more safe smuggling-wise to ignore.
}
}
if streamEnded || isHead {
res . Body = noBody
return res , nil
}
2017-05-11 16:39:54 +02:00
cs . bufPipe = pipe { b : & dataBuffer { expected : res . ContentLength } }
2016-11-19 11:03:41 +01:00
cs . bytesRemain = res . ContentLength
res . Body = transportResponseBody { cs }
go cs . awaitRequestCancel ( cs . req )
if cs . requestedGzip && res . Header . Get ( "Content-Encoding" ) == "gzip" {
res . Header . Del ( "Content-Encoding" )
res . Header . Del ( "Content-Length" )
res . ContentLength = - 1
res . Body = & gzipReader { body : res . Body }
setResponseUncompressed ( res )
}
return res , nil
}
func ( rl * clientConnReadLoop ) processTrailers ( cs * clientStream , f * MetaHeadersFrame ) error {
if cs . pastTrailers {
// Too many HEADERS frames for this stream.
return ConnectionError ( ErrCodeProtocol )
}
cs . pastTrailers = true
if ! f . StreamEnded ( ) {
// We expect that any headers for trailers also
// has END_STREAM.
return ConnectionError ( ErrCodeProtocol )
}
if len ( f . PseudoFields ( ) ) > 0 {
// No pseudo header fields are defined for trailers.
// TODO: ConnectionError might be overly harsh? Check.
return ConnectionError ( ErrCodeProtocol )
}
trailer := make ( http . Header )
for _ , hf := range f . RegularFields ( ) {
key := http . CanonicalHeaderKey ( hf . Name )
trailer [ key ] = append ( trailer [ key ] , hf . Value )
}
cs . trailer = trailer
rl . endStream ( cs )
return nil
}
// transportResponseBody is the concrete type of Transport.RoundTrip's
// Response.Body. It is an io.ReadCloser. On Read, it reads from cs.body.
// On Close it sends RST_STREAM if EOF wasn't already seen.
type transportResponseBody struct {
cs * clientStream
}
func ( b transportResponseBody ) Read ( p [ ] byte ) ( n int , err error ) {
cs := b . cs
cc := cs . cc
if cs . readErr != nil {
return 0 , cs . readErr
}
n , err = b . cs . bufPipe . Read ( p )
if cs . bytesRemain != - 1 {
if int64 ( n ) > cs . bytesRemain {
n = int ( cs . bytesRemain )
if err == nil {
err = errors . New ( "net/http: server replied with more than declared Content-Length; truncated" )
cc . writeStreamReset ( cs . ID , ErrCodeProtocol , err )
}
cs . readErr = err
return int ( cs . bytesRemain ) , err
}
cs . bytesRemain -= int64 ( n )
if err == io . EOF && cs . bytesRemain > 0 {
err = io . ErrUnexpectedEOF
cs . readErr = err
return n , err
}
}
if n == 0 {
// No flow control tokens to send back.
return
}
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
var connAdd , streamAdd int32
// Check the conn-level first, before the stream-level.
if v := cc . inflow . available ( ) ; v < transportDefaultConnFlow / 2 {
connAdd = transportDefaultConnFlow - v
cc . inflow . add ( connAdd )
}
if err == nil { // No need to refresh if the stream is over or failed.
// Consider any buffered body data (read from the conn but not
// consumed by the client) when computing flow control for this
// stream.
v := int ( cs . inflow . available ( ) ) + cs . bufPipe . Len ( )
if v < transportDefaultStreamFlow - transportDefaultStreamMinRefresh {
streamAdd = int32 ( transportDefaultStreamFlow - v )
cs . inflow . add ( streamAdd )
}
}
if connAdd != 0 || streamAdd != 0 {
cc . wmu . Lock ( )
defer cc . wmu . Unlock ( )
if connAdd != 0 {
cc . fr . WriteWindowUpdate ( 0 , mustUint31 ( connAdd ) )
}
if streamAdd != 0 {
cc . fr . WriteWindowUpdate ( cs . ID , mustUint31 ( streamAdd ) )
}
cc . bw . Flush ( )
}
return
}
var errClosedResponseBody = errors . New ( "http2: response body closed" )
func ( b transportResponseBody ) Close ( ) error {
cs := b . cs
cc := cs . cc
serverSentStreamEnd := cs . bufPipe . Err ( ) == io . EOF
unread := cs . bufPipe . Len ( )
if unread > 0 || ! serverSentStreamEnd {
cc . mu . Lock ( )
cc . wmu . Lock ( )
if ! serverSentStreamEnd {
cc . fr . WriteRSTStream ( cs . ID , ErrCodeCancel )
}
// Return connection-level flow control.
if unread > 0 {
cc . inflow . add ( int32 ( unread ) )
cc . fr . WriteWindowUpdate ( 0 , uint32 ( unread ) )
}
cc . bw . Flush ( )
cc . wmu . Unlock ( )
cc . mu . Unlock ( )
}
cs . bufPipe . BreakWithError ( errClosedResponseBody )
return nil
}
func ( rl * clientConnReadLoop ) processData ( f * DataFrame ) error {
cc := rl . cc
cs := cc . streamByID ( f . StreamID , f . StreamEnded ( ) )
data := f . Data ( )
if cs == nil {
cc . mu . Lock ( )
neverSent := cc . nextStreamID
cc . mu . Unlock ( )
if f . StreamID >= neverSent {
// We never asked for this.
cc . logf ( "http2: Transport received unsolicited DATA frame; closing connection" )
return ConnectionError ( ErrCodeProtocol )
}
// We probably did ask for this, but canceled. Just ignore it.
// TODO: be stricter here? only silently ignore things which
// we canceled, but not things which were closed normally
// by the peer? Tough without accumulating too much state.
// But at least return their flow control:
if f . Length > 0 {
cc . mu . Lock ( )
cc . inflow . add ( int32 ( f . Length ) )
cc . mu . Unlock ( )
cc . wmu . Lock ( )
cc . fr . WriteWindowUpdate ( 0 , uint32 ( f . Length ) )
cc . bw . Flush ( )
cc . wmu . Unlock ( )
}
return nil
}
if f . Length > 0 {
if len ( data ) > 0 && cs . bufPipe . b == nil {
// Data frame after it's already closed?
cc . logf ( "http2: Transport received DATA frame for closed stream; closing connection" )
return ConnectionError ( ErrCodeProtocol )
}
// Check connection-level flow control.
cc . mu . Lock ( )
if cs . inflow . available ( ) >= int32 ( f . Length ) {
cs . inflow . take ( int32 ( f . Length ) )
} else {
cc . mu . Unlock ( )
return ConnectionError ( ErrCodeFlowControl )
}
// Return any padded flow control now, since we won't
// refund it later on body reads.
if pad := int32 ( f . Length ) - int32 ( len ( data ) ) ; pad > 0 {
cs . inflow . add ( pad )
cc . inflow . add ( pad )
cc . wmu . Lock ( )
cc . fr . WriteWindowUpdate ( 0 , uint32 ( pad ) )
cc . fr . WriteWindowUpdate ( cs . ID , uint32 ( pad ) )
cc . bw . Flush ( )
cc . wmu . Unlock ( )
}
didReset := cs . didReset
cc . mu . Unlock ( )
if len ( data ) > 0 && ! didReset {
if _ , err := cs . bufPipe . Write ( data ) ; err != nil {
rl . endStreamError ( cs , err )
return err
}
}
}
if f . StreamEnded ( ) {
rl . endStream ( cs )
}
return nil
}
var errInvalidTrailers = errors . New ( "http2: invalid trailers" )
func ( rl * clientConnReadLoop ) endStream ( cs * clientStream ) {
// TODO: check that any declared content-length matches, like
// server.go's (*stream).endStream method.
rl . endStreamError ( cs , nil )
}
func ( rl * clientConnReadLoop ) endStreamError ( cs * clientStream , err error ) {
var code func ( )
if err == nil {
err = io . EOF
code = cs . copyTrailers
}
cs . bufPipe . closeWithErrorAndCode ( err , code )
delete ( rl . activeRes , cs . ID )
if isConnectionCloseRequest ( cs . req ) {
rl . closeWhenIdle = true
}
select {
case cs . resc <- resAndError { err : err } :
default :
}
}
func ( cs * clientStream ) copyTrailers ( ) {
for k , vv := range cs . trailer {
t := cs . resTrailer
if * t == nil {
* t = make ( http . Header )
}
( * t ) [ k ] = vv
}
}
func ( rl * clientConnReadLoop ) processGoAway ( f * GoAwayFrame ) error {
cc := rl . cc
cc . t . connPool ( ) . MarkDead ( cc )
if f . ErrCode != 0 {
// TODO: deal with GOAWAY more. particularly the error code
cc . vlogf ( "transport got GOAWAY with error code = %v" , f . ErrCode )
}
cc . setGoAway ( f )
return nil
}
func ( rl * clientConnReadLoop ) processSettings ( f * SettingsFrame ) error {
cc := rl . cc
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
if f . IsAck ( ) {
if cc . wantSettingsAck {
cc . wantSettingsAck = false
return nil
}
return ConnectionError ( ErrCodeProtocol )
}
err := f . ForeachSetting ( func ( s Setting ) error {
switch s . ID {
case SettingMaxFrameSize :
cc . maxFrameSize = s . Val
case SettingMaxConcurrentStreams :
cc . maxConcurrentStreams = s . Val
case SettingInitialWindowSize :
// 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.
if s . Val > math . MaxInt32 {
return ConnectionError ( ErrCodeFlowControl )
}
// Adjust flow control of currently-open
// frames by the difference of the old initial
// window size and this one.
delta := int32 ( s . Val ) - int32 ( cc . initialWindowSize )
for _ , cs := range cc . streams {
cs . flow . add ( delta )
}
cc . cond . Broadcast ( )
cc . initialWindowSize = s . Val
default :
// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
cc . vlogf ( "Unhandled Setting: %v" , s )
}
return nil
} )
if err != nil {
return err
}
cc . wmu . Lock ( )
defer cc . wmu . Unlock ( )
cc . fr . WriteSettingsAck ( )
cc . bw . Flush ( )
return cc . werr
}
func ( rl * clientConnReadLoop ) processWindowUpdate ( f * WindowUpdateFrame ) error {
cc := rl . cc
cs := cc . streamByID ( f . StreamID , false )
if f . StreamID != 0 && cs == nil {
return nil
}
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
fl := & cc . flow
if cs != nil {
fl = & cs . flow
}
if ! fl . add ( int32 ( f . Increment ) ) {
return ConnectionError ( ErrCodeFlowControl )
}
cc . cond . Broadcast ( )
return nil
}
func ( rl * clientConnReadLoop ) processResetStream ( f * RSTStreamFrame ) error {
cs := rl . cc . streamByID ( f . StreamID , true )
if cs == nil {
// TODO: return error if server tries to RST_STEAM an idle stream
return nil
}
select {
case <- cs . peerReset :
// Already reset.
// This is the only goroutine
// which closes this, so there
// isn't a race.
default :
err := streamError ( cs . ID , f . ErrCode )
cs . resetErr = err
close ( cs . peerReset )
cs . bufPipe . CloseWithError ( err )
cs . cc . cond . Broadcast ( ) // wake up checkResetOrDone via clientStream.awaitFlowControl
}
delete ( rl . activeRes , cs . ID )
return nil
}
// Ping sends a PING frame to the server and waits for the ack.
// Public implementation is in go17.go and not_go17.go
func ( cc * ClientConn ) ping ( ctx contextContext ) error {
c := make ( chan struct { } )
// Generate a random payload
var p [ 8 ] byte
for {
if _ , err := rand . Read ( p [ : ] ) ; err != nil {
return err
}
cc . mu . Lock ( )
// check for dup before insert
if _ , found := cc . pings [ p ] ; ! found {
cc . pings [ p ] = c
cc . mu . Unlock ( )
break
}
cc . mu . Unlock ( )
}
cc . wmu . Lock ( )
if err := cc . fr . WritePing ( false , p ) ; err != nil {
cc . wmu . Unlock ( )
return err
}
if err := cc . bw . Flush ( ) ; err != nil {
cc . wmu . Unlock ( )
return err
}
cc . wmu . Unlock ( )
select {
case <- c :
return nil
case <- ctx . Done ( ) :
return ctx . Err ( )
case <- cc . readerDone :
// connection closed
return cc . readerErr
}
}
func ( rl * clientConnReadLoop ) processPing ( f * PingFrame ) error {
if f . IsAck ( ) {
cc := rl . cc
cc . mu . Lock ( )
defer cc . mu . Unlock ( )
// If ack, notify listener if any
if c , ok := cc . pings [ f . Data ] ; ok {
close ( c )
delete ( cc . pings , f . Data )
}
return nil
}
cc := rl . cc
cc . wmu . Lock ( )
defer cc . wmu . Unlock ( )
if err := cc . fr . WritePing ( true , f . Data ) ; err != nil {
return err
}
return cc . bw . Flush ( )
}
func ( rl * clientConnReadLoop ) processPushPromise ( f * PushPromiseFrame ) error {
// We told the peer we don't want them.
// Spec says:
// "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH
// setting of the peer endpoint is set to 0. An endpoint that
// has set this setting and has received acknowledgement MUST
// treat the receipt of a PUSH_PROMISE frame as a connection
// error (Section 5.4.1) of type PROTOCOL_ERROR."
return ConnectionError ( ErrCodeProtocol )
}
func ( cc * ClientConn ) writeStreamReset ( streamID uint32 , code ErrCode , err error ) {
// TODO: map err to more interesting error codes, once the
// HTTP community comes up with some. But currently for
// RST_STREAM there's no equivalent to GOAWAY frame's debug
// data, and the error codes are all pretty vague ("cancel").
cc . wmu . Lock ( )
cc . fr . WriteRSTStream ( streamID , code )
cc . bw . Flush ( )
cc . wmu . Unlock ( )
}
var (
errResponseHeaderListSize = errors . New ( "http2: response header list larger than advertised limit" )
errPseudoTrailers = errors . New ( "http2: invalid pseudo header in trailers" )
)
func ( cc * ClientConn ) logf ( format string , args ... interface { } ) {
cc . t . logf ( format , args ... )
}
func ( cc * ClientConn ) vlogf ( format string , args ... interface { } ) {
cc . t . vlogf ( format , args ... )
}
func ( t * Transport ) vlogf ( format string , args ... interface { } ) {
if VerboseLogs {
t . logf ( format , args ... )
}
}
func ( t * Transport ) logf ( format string , args ... interface { } ) {
log . Printf ( format , args ... )
}
var noBody io . ReadCloser = ioutil . NopCloser ( bytes . NewReader ( nil ) )
func strSliceContains ( ss [ ] string , s string ) bool {
for _ , v := range ss {
if v == s {
return true
}
}
return false
}
type erringRoundTripper struct { err error }
func ( rt erringRoundTripper ) RoundTrip ( * http . Request ) ( * http . Response , error ) { return nil , rt . err }
// gzipReader wraps a response body so it can lazily
// call gzip.NewReader on the first call to Read
type gzipReader struct {
body io . ReadCloser // underlying Response.Body
zr * gzip . Reader // lazily-initialized gzip reader
zerr error // sticky error
}
func ( gz * gzipReader ) Read ( p [ ] byte ) ( n int , err error ) {
if gz . zerr != nil {
return 0 , gz . zerr
}
if gz . zr == nil {
gz . zr , err = gzip . NewReader ( gz . body )
if err != nil {
gz . zerr = err
return 0 , err
}
}
return gz . zr . Read ( p )
}
func ( gz * gzipReader ) Close ( ) error {
return gz . body . Close ( )
}
type errorReader struct { err error }
func ( r errorReader ) Read ( p [ ] byte ) ( int , error ) { return 0 , r . err }
// bodyWriterState encapsulates various state around the Transport's writing
// of the request body, particularly regarding doing delayed writes of the body
// when the request contains "Expect: 100-continue".
type bodyWriterState struct {
cs * clientStream
timer * time . Timer // if non-nil, we're doing a delayed write
fnonce * sync . Once // to call fn with
fn func ( ) // the code to run in the goroutine, writing the body
resc chan error // result of fn's execution
delay time . Duration // how long we should delay a delayed write for
}
func ( t * Transport ) getBodyWriterState ( cs * clientStream , body io . Reader ) ( s bodyWriterState ) {
s . cs = cs
if body == nil {
return
}
resc := make ( chan error , 1 )
s . resc = resc
s . fn = func ( ) {
2017-01-02 17:12:05 +01:00
cs . cc . mu . Lock ( )
cs . startedWrite = true
cs . cc . mu . Unlock ( )
2016-11-19 11:03:41 +01:00
resc <- cs . writeRequestBody ( body , cs . req . Body )
}
s . delay = t . expectContinueTimeout ( )
if s . delay == 0 ||
! httplex . HeaderValuesContainsToken (
cs . req . Header [ "Expect" ] ,
"100-continue" ) {
return
}
s . fnonce = new ( sync . Once )
// Arm the timer with a very large duration, which we'll
// intentionally lower later. It has to be large now because
// we need a handle to it before writing the headers, but the
// s.delay value is defined to not start until after the
// request headers were written.
const hugeDuration = 365 * 24 * time . Hour
s . timer = time . AfterFunc ( hugeDuration , func ( ) {
s . fnonce . Do ( s . fn )
} )
return
}
func ( s bodyWriterState ) cancel ( ) {
if s . timer != nil {
s . timer . Stop ( )
}
}
func ( s bodyWriterState ) on100 ( ) {
if s . timer == nil {
// If we didn't do a delayed write, ignore the server's
// bogus 100 continue response.
return
}
s . timer . Stop ( )
go func ( ) { s . fnonce . Do ( s . fn ) } ( )
}
// scheduleBodyWrite starts writing the body, either immediately (in
// the common case) or after the delay timeout. It should not be
// called until after the headers have been written.
func ( s bodyWriterState ) scheduleBodyWrite ( ) {
if s . timer == nil {
// We're not doing a delayed write (see
// getBodyWriterState), so just start the writing
// goroutine immediately.
go s . fn ( )
return
}
traceWait100Continue ( s . cs . trace )
if s . timer . Stop ( ) {
s . timer . Reset ( s . delay )
}
}
// isConnectionCloseRequest reports whether req should use its own
// connection for a single request and then close the connection.
func isConnectionCloseRequest ( req * http . Request ) bool {
return req . Close || httplex . HeaderValuesContainsToken ( req . Header [ "Connection" ] , "close" )
}