updated vendor

vendor/golang.org/x/net/http2/README.md

@@ -0,0 +1,19 @@
+This package (golang.org/x/net/http2) is the original source of truth
+of the Go HTTP/2 implementation.
+
+As of Go 1.27, the source of truth has moved to the standard library
+package net/http/internal/http2.
+All new feature development should happen in that package.
+Only critical bug fixes and security fixes will be backported to x/net.
+
+The x/net package contains two implementations of the HTTP/2 transport and server:
+
+The original implementation (no longer the source of truth).
+
+A reimplementation of the x/net/http2 APIs in terms of net/http.
+This is called "the wrapping implementation", since it wraps net/http.
+
+The original implementation is used when the Go version is less than 1.27.
+
+The wrapping implementation is used when the Go version is at least 1.27.
+The build tag "http2legacy" may be set to use the original implementation.

vendor/golang.org/x/net/http2/client_conn_pool.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 // Transport code's client connection pooling.
 
 package http2
@@ -14,18 +16,6 @@ import (
 	"sync"
 )
 
-// ClientConnPool manages a pool of HTTP/2 client connections.
-type ClientConnPool interface {
-	// GetClientConn returns a specific HTTP/2 connection (usually
-	// a TLS-TCP connection) to an HTTP/2 server. On success, the
-	// returned ClientConn accounts for the upcoming RoundTrip
-	// call, so the caller should not omit it. If the caller needs
-	// to, ClientConn.RoundTrip can be called with a bogus
-	// new(http.Request) to release the stream reservation.
-	GetClientConn(req *http.Request, addr string) (*ClientConn, error)
-	MarkDead(*ClientConn)
-}
-
 // clientConnPoolIdleCloser is the interface implemented by ClientConnPool
 // implementations which can close their idle connections.
 type clientConnPoolIdleCloser interface {

vendor/golang.org/x/net/http2/client_priority_go126.go

@@ -0,0 +1,20 @@
+// Copyright 2026 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.
+
+//go:build !go1.27
+
+package http2
+
+import "net/http"
+
+// Support for go.dev/issue/75500 is added in Go 1.27. In case anyone uses
+// x/net with versions before Go 1.27, we return true here so that their write
+// scheduler will still be the round-robin write scheduler rather than the RFC
+// 9218 write scheduler. That way, older users of Go will not see a sudden
+// change of behavior just from importing x/net.
+//
+// TODO(nsh): remove this file after x/net go.mod is at Go 1.27.
+func clientPriorityDisabled(_ *http.Server) bool {
+	return true
+}

vendor/golang.org/x/net/http2/client_priority_go127.go

@@ -0,0 +1,13 @@
+// Copyright 2026 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.
+
+//go:build go1.27
+
+package http2
+
+import "net/http"
+
+func clientPriorityDisabled(s *http.Server) bool {
+	return s.DisableClientPriority
+}

vendor/golang.org/x/net/http2/clientconn.go

@@ -0,0 +1,57 @@
+// Copyright 2026 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 (
+	"context"
+	"net/http"
+)
+
+func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
+	return cc.roundTrip(req)
+}
+
+// SetDoNotReuse marks cc as not reusable for future HTTP requests.
+func (cc *ClientConn) SetDoNotReuse() {
+	cc.setDoNotReuse()
+}
+
+// CanTakeNewRequest reports whether the connection can take a new request,
+// meaning it has not been closed or received or sent a GOAWAY.
+//
+// If the caller is going to immediately make a new request on this
+// connection, use ReserveNewRequest instead.
+func (cc *ClientConn) CanTakeNewRequest() bool {
+	return cc.canTakeNewRequest()
+}
+
+// ReserveNewRequest is like CanTakeNewRequest but also reserves a
+// concurrent stream in cc. The reservation is decremented on the
+// next call to RoundTrip.
+func (cc *ClientConn) ReserveNewRequest() bool {
+	return cc.reserveNewRequest()
+}
+
+// State returns a snapshot of cc's state.
+func (cc *ClientConn) State() ClientConnState {
+	return cc.state()
+}
+
+// Shutdown gracefully closes the client connection, waiting for running streams to complete.
+func (cc *ClientConn) Shutdown(ctx context.Context) error {
+	return cc.shutdown(ctx)
+}
+
+// Close closes the client connection immediately.
+//
+// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
+func (cc *ClientConn) Close() error {
+	return cc.close()
+}
+
+// Ping sends a PING frame to the server and waits for the ack.
+func (cc *ClientConn) Ping(ctx context.Context) error {
+	return cc.ping(ctx)
+}

vendor/golang.org/x/net/http2/config.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import (

vendor/golang.org/x/net/http2/frame.go

@@ -11,11 +11,13 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"slices"
 	"strings"
 	"sync"
 
 	"golang.org/x/net/http/httpguts"
 	"golang.org/x/net/http2/hpack"
+	"golang.org/x/net/internal/httpsfv"
 )
 
 const frameHeaderLen = 9
@@ -23,33 +25,36 @@ const frameHeaderLen = 9
 var padZeros = make([]byte, 255) // zeros for padding
 
 // A FrameType is a registered frame type as defined in
-// https://httpwg.org/specs/rfc7540.html#rfc.section.11.2
+// https://httpwg.org/specs/rfc7540.html#rfc.section.11.2 and other future
+// RFCs.
 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
+	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
+	FramePriorityUpdate FrameType = 0x10
 )
 
 var frameNames = [...]string{
-	FrameData:         "DATA",
-	FrameHeaders:      "HEADERS",
-	FramePriority:     "PRIORITY",
-	FrameRSTStream:    "RST_STREAM",
-	FrameSettings:     "SETTINGS",
-	FramePushPromise:  "PUSH_PROMISE",
-	FramePing:         "PING",
-	FrameGoAway:       "GOAWAY",
-	FrameWindowUpdate: "WINDOW_UPDATE",
-	FrameContinuation: "CONTINUATION",
+	FrameData:           "DATA",
+	FrameHeaders:        "HEADERS",
+	FramePriority:       "PRIORITY",
+	FrameRSTStream:      "RST_STREAM",
+	FrameSettings:       "SETTINGS",
+	FramePushPromise:    "PUSH_PROMISE",
+	FramePing:           "PING",
+	FrameGoAway:         "GOAWAY",
+	FrameWindowUpdate:   "WINDOW_UPDATE",
+	FrameContinuation:   "CONTINUATION",
+	FramePriorityUpdate: "PRIORITY_UPDATE",
 }
 
 func (t FrameType) String() string {
@@ -125,21 +130,24 @@ var flagName = map[FrameType]map[Flags]string{
 type frameParser func(fc *frameCache, fh FrameHeader, countError func(string), payload []byte) (Frame, error)
 
 var frameParsers = [...]frameParser{
-	FrameData:         parseDataFrame,
-	FrameHeaders:      parseHeadersFrame,
-	FramePriority:     parsePriorityFrame,
-	FrameRSTStream:    parseRSTStreamFrame,
-	FrameSettings:     parseSettingsFrame,
-	FramePushPromise:  parsePushPromise,
-	FramePing:         parsePingFrame,
-	FrameGoAway:       parseGoAwayFrame,
-	FrameWindowUpdate: parseWindowUpdateFrame,
-	FrameContinuation: parseContinuationFrame,
+	FrameData:           parseDataFrame,
+	FrameHeaders:        parseHeadersFrame,
+	FramePriority:       parsePriorityFrame,
+	FrameRSTStream:      parseRSTStreamFrame,
+	FrameSettings:       parseSettingsFrame,
+	FramePushPromise:    parsePushPromise,
+	FramePing:           parsePingFrame,
+	FrameGoAway:         parseGoAwayFrame,
+	FrameWindowUpdate:   parseWindowUpdateFrame,
+	FrameContinuation:   parseContinuationFrame,
+	FramePriorityUpdate: parsePriorityUpdateFrame,
 }
 
 func typeFrameParser(t FrameType) frameParser {
 	if int(t) < len(frameParsers) {
-		return frameParsers[t]
+		if f := frameParsers[t]; f != nil {
+			return f
+		}
 	}
 	return parseUnknownFrame
 }
@@ -1180,9 +1188,34 @@ type PriorityFrame struct {
 	PriorityParam
 }
 
-var defaultRFC9218Priority = PriorityParam{
-	incremental: 0,
-	urgency:     3,
+// defaultRFC9218Priority determines what priority we should use as the default
+// value.
+//
+// According to RFC 9218, by default, streams should be given an urgency of 3
+// and should be non-incremental. However, making streams non-incremental by
+// default would be a huge change to our historical behavior where we would
+// round-robin writes across streams. When streams are non-incremental, we
+// would process streams of the same urgency one-by-one to completion instead.
+//
+// To avoid such a sudden change which might break some HTTP/2 users, this
+// function allows the caller to specify whether they can actually use the
+// default value as specified in RFC 9218. If not, this function will return a
+// priority value where streams are incremental by default instead: effectively
+// a round-robin between stream of the same urgency.
+//
+// As an example, a server might not be able to use the RFC 9218 default value
+// when it's not sure that the client it is serving is aware of RFC 9218.
+func defaultRFC9218Priority(canUseDefault bool) PriorityParam {
+	if canUseDefault {
+		return PriorityParam{
+			urgency:     3,
+			incremental: 0,
+		}
+	}
+	return PriorityParam{
+		urgency:     3,
+		incremental: 1,
+	}
 }
 
 // Note that HTTP/2 has had two different prioritization schemes, and
@@ -1266,6 +1299,74 @@ func (f *Framer) WritePriority(streamID uint32, p PriorityParam) error {
 	return f.endWrite()
 }
 
+// PriorityUpdateFrame is a PRIORITY_UPDATE frame as described in
+// https://www.rfc-editor.org/rfc/rfc9218.html#name-the-priority_update-frame.
+type PriorityUpdateFrame struct {
+	FrameHeader
+	Priority            string
+	PrioritizedStreamID uint32
+}
+
+func parseRFC9218Priority(s string, canUseDefault bool) (p PriorityParam, ok bool) {
+	p = defaultRFC9218Priority(canUseDefault)
+	ok = httpsfv.ParseDictionary(s, func(key, val, _ string) {
+		switch key {
+		case "u":
+			if u, ok := httpsfv.ParseInteger(val); ok && u >= 0 && u <= 7 {
+				p.urgency = uint8(u)
+			}
+		case "i":
+			if i, ok := httpsfv.ParseBoolean(val); ok {
+				if i {
+					p.incremental = 1
+				} else {
+					p.incremental = 0
+				}
+			}
+		}
+	})
+	if !ok {
+		return defaultRFC9218Priority(canUseDefault), ok
+	}
+	return p, true
+}
+
+func parsePriorityUpdateFrame(_ *frameCache, fh FrameHeader, countError func(string), payload []byte) (Frame, error) {
+	if fh.StreamID != 0 {
+		countError("frame_priority_update_non_zero_stream")
+		return nil, connError{ErrCodeProtocol, "PRIORITY_UPDATE frame with non-zero stream ID"}
+	}
+	if len(payload) < 4 {
+		countError("frame_priority_update_bad_length")
+		return nil, connError{ErrCodeFrameSize, fmt.Sprintf("PRIORITY_UPDATE frame payload size was %d; want at least 4", len(payload))}
+	}
+	v := binary.BigEndian.Uint32(payload[:4])
+	streamID := v & 0x7fffffff // mask off high bit
+	if streamID == 0 {
+		countError("frame_priority_update_prioritizing_zero_stream")
+		return nil, connError{ErrCodeProtocol, "PRIORITY_UPDATE frame with prioritized stream ID of zero"}
+	}
+	return &PriorityUpdateFrame{
+		FrameHeader:         fh,
+		PrioritizedStreamID: streamID,
+		Priority:            string(payload[4:]),
+	}, nil
+}
+
+// WritePriorityUpdate writes a PRIORITY_UPDATE 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) WritePriorityUpdate(streamID uint32, priority string) error {
+	if !validStreamID(streamID) && !f.AllowIllegalWrites {
+		return errStreamID
+	}
+	f.startWrite(FramePriorityUpdate, 0, 0)
+	f.writeUint32(streamID)
+	f.writeBytes([]byte(priority))
+	return f.endWrite()
+}
+
 // A RSTStreamFrame allows for abnormal termination of a stream.
 // See https://httpwg.org/specs/rfc7540.html#rfc.section.6.4
 type RSTStreamFrame struct {
@@ -1547,6 +1648,23 @@ func (mh *MetaHeadersFrame) PseudoFields() []hpack.HeaderField {
 	return mh.Fields
 }
 
+func (mh *MetaHeadersFrame) rfc9218Priority(priorityAware bool) (p PriorityParam, priorityAwareAfter, hasIntermediary bool) {
+	var s string
+	for _, field := range mh.Fields {
+		if field.Name == "priority" {
+			s = field.Value
+			priorityAware = true
+		}
+		if slices.Contains([]string{"via", "forwarded", "x-forwarded-for"}, field.Name) {
+			hasIntermediary = true
+		}
+	}
+	// No need to check for ok. parseRFC9218Priority will return a default
+	// value if there is no priority field or if the field cannot be parsed.
+	p, _ = parseRFC9218Priority(s, priorityAware && !hasIntermediary)
+	return p, priorityAware, hasIntermediary
+}
+
 func (mh *MetaHeadersFrame) checkPseudos() error {
 	var isRequest, isResponse bool
 	pf := mh.PseudoFields()

vendor/golang.org/x/net/http2/http2.go

@@ -4,13 +4,17 @@
 
 // Package http2 implements the HTTP/2 protocol.
 //
-// This package is low-level and intended to be used directly by very
-// few people. Most users will use it indirectly through the automatic
-// use by the net/http package (from Go 1.6 and later).
-// For use in earlier Go versions see ConfigureServer. (Transport support
-// requires Go 1.6 or later)
+// Almost no users should need to import this package directly.
+// The net/http package supports HTTP/2 natively.
 //
-// See https://http2.github.io/ for more information on HTTP/2.
+// To enable or disable HTTP/2 support in net/http clients and servers, see
+// [http.Transport.Protocols] and [http.Server.Protocols].
+//
+// To configure HTTP/2 parameters, see
+// [http.Transport.HTTP2] and [http.Server.HTTP2].
+//
+// To create HTTP/1 or HTTP/2 connections, see
+// [http.Transport.NewClientConn].
 package http2 // import "golang.org/x/net/http2"
 
 import (
@@ -169,6 +173,7 @@ const (
 	SettingMaxFrameSize          SettingID = 0x5
 	SettingMaxHeaderListSize     SettingID = 0x6
 	SettingEnableConnectProtocol SettingID = 0x8
+	SettingNoRFC7540Priorities   SettingID = 0x9
 )
 
 var settingName = map[SettingID]string{
@@ -179,6 +184,7 @@ var settingName = map[SettingID]string{
 	SettingMaxFrameSize:          "MAX_FRAME_SIZE",
 	SettingMaxHeaderListSize:     "MAX_HEADER_LIST_SIZE",
 	SettingEnableConnectProtocol: "ENABLE_CONNECT_PROTOCOL",
+	SettingNoRFC7540Priorities:   "NO_RFC7540_PRIORITIES",
 }
 
 func (s SettingID) String() string {
@@ -189,7 +195,7 @@ func (s SettingID) String() string {
 }
 
 // validWireHeaderFieldName reports whether v is a valid header field
-// name (key). See httpguts.ValidHeaderName for the base rules.
+// name (key). See httpguts.ValidHeaderFieldName for the base rules.
 //
 // Further, http2 says:
 //

vendor/golang.org/x/net/http2/server.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 // TODO: turn off the serve goroutine when idle, so
 // an idle conn only has the readFrames goroutine active. (which could
 // also be optimized probably to pin less memory in crypto/tls). This
@@ -88,96 +90,6 @@ var (
 	testHookOnPanic       func(sc *serverConn, panicVal interface{}) (rePanic bool)
 )
 
-// Server is an HTTP/2 server.
-type Server struct {
-	// MaxHandlers limits the number of http.Handler ServeHTTP goroutines
-	// which may run at a time over all connections.
-	// Negative or zero no limit.
-	// TODO: implement
-	MaxHandlers int
-
-	// MaxConcurrentStreams optionally specifies the number of
-	// concurrent streams that each client may have open at a
-	// time. This is unrelated to the number of http.Handler goroutines
-	// which may be active globally, which is MaxHandlers.
-	// If zero, MaxConcurrentStreams defaults to at least 100, per
-	// the HTTP/2 spec's recommendations.
-	MaxConcurrentStreams uint32
-
-	// MaxDecoderHeaderTableSize optionally specifies the http2
-	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
-	// informs the remote endpoint of the maximum size of the header compression
-	// table used to decode header blocks, in octets. If zero, the default value
-	// of 4096 is used.
-	MaxDecoderHeaderTableSize uint32
-
-	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
-	// header compression table used for encoding request headers. Received
-	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
-	// the default value of 4096 is used.
-	MaxEncoderHeaderTableSize uint32
-
-	// MaxReadFrameSize optionally specifies the largest frame
-	// this server is willing to read. A valid value is between
-	// 16k and 16M, inclusive. If zero or otherwise invalid, a
-	// default value is used.
-	MaxReadFrameSize uint32
-
-	// PermitProhibitedCipherSuites, if true, permits the use of
-	// cipher suites prohibited by the HTTP/2 spec.
-	PermitProhibitedCipherSuites bool
-
-	// IdleTimeout specifies how long until idle clients should be
-	// closed with a GOAWAY frame. PING frames are not considered
-	// activity for the purposes of IdleTimeout.
-	// If zero or negative, there is no timeout.
-	IdleTimeout time.Duration
-
-	// ReadIdleTimeout is the timeout after which a health check using a ping
-	// frame will be carried out if no frame is received on the connection.
-	// If zero, no health check is performed.
-	ReadIdleTimeout time.Duration
-
-	// PingTimeout is the timeout after which the connection will be closed
-	// if a response to a ping is not received.
-	// If zero, a default of 15 seconds is used.
-	PingTimeout time.Duration
-
-	// WriteByteTimeout is the timeout after which a connection will be
-	// closed if no data can be written to it. The timeout begins when data is
-	// available to write, and is extended whenever any bytes are written.
-	// If zero or negative, there is no timeout.
-	WriteByteTimeout time.Duration
-
-	// MaxUploadBufferPerConnection is the size of the initial flow
-	// control window for each connections. The HTTP/2 spec does not
-	// allow this to be smaller than 65535 or larger than 2^32-1.
-	// If the value is outside this range, a default value will be
-	// used instead.
-	MaxUploadBufferPerConnection int32
-
-	// MaxUploadBufferPerStream is the size of the initial flow control
-	// window for each stream. The HTTP/2 spec does not allow this to
-	// be larger than 2^32-1. If the value is zero or larger than the
-	// maximum, a default value will be used instead.
-	MaxUploadBufferPerStream int32
-
-	// NewWriteScheduler constructs a write scheduler for a connection.
-	// If nil, a default scheduler is chosen.
-	NewWriteScheduler func() WriteScheduler
-
-	// CountError, if non-nil, is called on HTTP/2 server errors.
-	// It's intended to increment a metric for monitoring, such
-	// as an expvar or Prometheus metric.
-	// The errType consists of only ASCII word characters.
-	CountError func(errType string)
-
-	// Internal state. This is a pointer (rather than embedded directly)
-	// so that we don't embed a Mutex in this struct, which will make the
-	// struct non-copyable, which might break some callers.
-	state *serverInternalState
-}
-
 type serverInternalState struct {
 	mu          sync.Mutex
 	activeConns map[*serverConn]struct{}
@@ -185,6 +97,9 @@ type serverInternalState struct {
 	// Pool of error channels. This is per-Server rather than global
 	// because channels can't be reused across synctest bubbles.
 	errChanPool sync.Pool
+
+	// Used in tests.
+	testNewConn func(*serverConn)
 }
 
 func (s *serverInternalState) registerConn(sc *serverConn) {
@@ -237,12 +152,7 @@ func (s *serverInternalState) putErrChan(ch chan error) {
 	s.errChanPool.Put(ch)
 }
 
-// ConfigureServer adds HTTP/2 support to a net/http Server.
-//
-// The configuration conf may be nil.
-//
-// ConfigureServer must be called before s begins serving.
-func ConfigureServer(s *http.Server, conf *Server) error {
+func configureServer(s *http.Server, conf *Server) error {
 	if s == nil {
 		panic("nil *http.Server")
 	}
@@ -347,83 +257,6 @@ func ConfigureServer(s *http.Server, conf *Server) error {
 	return nil
 }
 
-// ServeConnOpts are options for the Server.ServeConn method.
-type ServeConnOpts struct {
-	// Context is the base context to use.
-	// If nil, context.Background is used.
-	Context context.Context
-
-	// BaseConfig optionally sets the base configuration
-	// for values. If nil, defaults are used.
-	BaseConfig *http.Server
-
-	// Handler specifies which handler to use for processing
-	// requests. If nil, BaseConfig.Handler is used. If BaseConfig
-	// or BaseConfig.Handler is nil, http.DefaultServeMux is used.
-	Handler http.Handler
-
-	// UpgradeRequest is an initial request received on a connection
-	// undergoing an h2c upgrade. The request body must have been
-	// completely read from the connection before calling ServeConn,
-	// and the 101 Switching Protocols response written.
-	UpgradeRequest *http.Request
-
-	// Settings is the decoded contents of the HTTP2-Settings header
-	// in an h2c upgrade request.
-	Settings []byte
-
-	// SawClientPreface is set if the HTTP/2 connection preface
-	// has already been read from the connection.
-	SawClientPreface bool
-}
-
-func (o *ServeConnOpts) context() context.Context {
-	if o != nil && o.Context != nil {
-		return o.Context
-	}
-	return context.Background()
-}
-
-func (o *ServeConnOpts) baseConfig() *http.Server {
-	if o != nil && o.BaseConfig != nil {
-		return o.BaseConfig
-	}
-	return new(http.Server)
-}
-
-func (o *ServeConnOpts) handler() http.Handler {
-	if o != nil {
-		if o.Handler != nil {
-			return o.Handler
-		}
-		if o.BaseConfig != nil && o.BaseConfig.Handler != nil {
-			return o.BaseConfig.Handler
-		}
-	}
-	return http.DefaultServeMux
-}
-
-// ServeConn serves HTTP/2 requests on the provided connection and
-// blocks until the connection is no longer readable.
-//
-// ServeConn starts speaking HTTP/2 assuming that c has not had any
-// reads or writes. It writes its initial settings frame and expects
-// to be able to read the preface and settings frame from the
-// client. If c has a ConnectionState method like a *tls.Conn, the
-// ConnectionState is used to verify the TLS ciphersuite and to set
-// the Request.TLS field in Handlers.
-//
-// ServeConn does not support h2c by itself. Any h2c support must be
-// implemented in terms of providing a suitably-behaving net.Conn.
-//
-// The opts parameter is optional. If nil, default values are used.
-func (s *Server) ServeConn(c net.Conn, opts *ServeConnOpts) {
-	if opts == nil {
-		opts = &ServeConnOpts{}
-	}
-	s.serveConn(c, opts, nil)
-}
-
 func (s *Server) serveConn(c net.Conn, opts *ServeConnOpts, newf func(*serverConn)) {
 	baseCtx, cancel := serverConnBaseContext(c, opts)
 	defer cancel()
@@ -459,6 +292,9 @@ func (s *Server) serveConn(c net.Conn, opts *ServeConnOpts, newf func(*serverCon
 	if newf != nil {
 		newf(sc)
 	}
+	if s.state != nil && s.state.testNewConn != nil {
+		s.state.testNewConn(sc)
+	}
 
 	s.state.registerConn(sc)
 	defer s.state.unregisterConn(sc)
@@ -472,10 +308,13 @@ func (s *Server) serveConn(c net.Conn, opts *ServeConnOpts, newf func(*serverCon
 		sc.conn.SetWriteDeadline(time.Time{})
 	}
 
-	if s.NewWriteScheduler != nil {
+	switch {
+	case s.NewWriteScheduler != nil:
 		sc.writeSched = s.NewWriteScheduler()
-	} else {
+	case clientPriorityDisabled(http1srv):
 		sc.writeSched = newRoundRobinWriteScheduler()
+	default:
+		sc.writeSched = newPriorityWriteSchedulerRFC9218()
 	}
 
 	// These start at the RFC-specified defaults. If there is a higher
@@ -565,15 +404,6 @@ func (s *Server) serveConn(c net.Conn, opts *ServeConnOpts, newf func(*serverCon
 	sc.serve(conf)
 }
 
-func serverConnBaseContext(c net.Conn, opts *ServeConnOpts) (ctx context.Context, cancel func()) {
-	ctx, cancel = context.WithCancel(opts.context())
-	ctx = context.WithValue(ctx, http.LocalAddrContextKey, c.LocalAddr())
-	if hs := opts.baseConfig(); hs != nil {
-		ctx = context.WithValue(ctx, http.ServerContextKey, hs)
-	}
-	return
-}
-
 func (sc *serverConn) rejectConn(err ErrCode, debug string) {
 	sc.vlogf("http2: server rejecting conn: %v, %s", err, debug)
 	// ignoring errors. hanging up anyway.
@@ -648,6 +478,23 @@ type serverConn struct {
 
 	// Used by startGracefulShutdown.
 	shutdownOnce sync.Once
+
+	// Used for RFC 9218 prioritization.
+	hasIntermediary bool // connection is done via an intermediary / proxy
+	priorityAware   bool // the client has sent priority signal, meaning that it is aware of it.
+}
+
+func (sc *serverConn) writeSchedIgnoresRFC7540() bool {
+	switch sc.writeSched.(type) {
+	case *priorityWriteSchedulerRFC9218:
+		return true
+	case *randomWriteScheduler:
+		return true
+	case *roundRobinWriteScheduler:
+		return true
+	default:
+		return false
+	}
 }
 
 func (sc *serverConn) maxHeaderListSize() uint32 {
@@ -938,6 +785,9 @@ func (sc *serverConn) serve(conf http2Config) {
 	if !disableExtendedConnectProtocol {
 		settings = append(settings, Setting{SettingEnableConnectProtocol, 1})
 	}
+	if sc.writeSchedIgnoresRFC7540() {
+		settings = append(settings, Setting{SettingNoRFC7540Priorities, 1})
+	}
 	sc.writeFrame(FrameWriteRequest{
 		write: settings,
 	})
@@ -1623,6 +1473,8 @@ func (sc *serverConn) processFrame(f Frame) error {
 		// A client cannot push. Thus, servers MUST treat the receipt of a PUSH_PROMISE
 		// frame as a connection error (Section 5.4.1) of type PROTOCOL_ERROR.
 		return sc.countError("push_promise", ConnectionError(ErrCodeProtocol))
+	case *PriorityUpdateFrame:
+		return sc.processPriorityUpdate(f)
 	default:
 		sc.vlogf("http2: server ignoring frame: %v", f.Header())
 		return nil
@@ -1803,6 +1655,10 @@ func (sc *serverConn) processSetting(s Setting) error {
 	case SettingEnableConnectProtocol:
 		// Receipt of this parameter by a server does not
 		// have any impact
+	case SettingNoRFC7540Priorities:
+		if s.Val > 1 {
+			return ConnectionError(ErrCodeProtocol)
+		}
 	default:
 		// Unknown setting: "An endpoint that receives a SETTINGS
 		// frame with any unknown or unsupported identifier MUST
@@ -2073,13 +1929,33 @@ func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error {
 	if f.StreamEnded() {
 		initialState = stateHalfClosedRemote
 	}
-	st := sc.newStream(id, 0, initialState)
+
+	// We are handling two special cases here:
+	// 1. When a request is sent via an intermediary, we force priority to be
+	// u=3,i. This is essentially a round-robin behavior, and is done to ensure
+	// fairness between, for example, multiple clients using the same proxy.
+	// 2. Until a client has shown that it is aware of RFC 9218, we make its
+	// streams non-incremental by default. This is done to preserve the
+	// historical behavior of handling streams in a round-robin manner, rather
+	// than one-by-one to completion.
+	initialPriority := defaultRFC9218Priority(sc.priorityAware && !sc.hasIntermediary)
+	if _, ok := sc.writeSched.(*priorityWriteSchedulerRFC9218); ok && !sc.hasIntermediary {
+		headerPriority, priorityAware, hasIntermediary := f.rfc9218Priority(sc.priorityAware)
+		initialPriority = headerPriority
+		sc.hasIntermediary = hasIntermediary
+		if priorityAware {
+			sc.priorityAware = true
+		}
+	}
+	st := sc.newStream(id, 0, initialState, initialPriority)
 
 	if f.HasPriority() {
 		if err := sc.checkPriority(f.StreamID, f.Priority); err != nil {
 			return err
 		}
-		sc.writeSched.AdjustStream(st.id, f.Priority)
+		if !sc.writeSchedIgnoresRFC7540() {
+			sc.writeSched.AdjustStream(st.id, f.Priority)
+		}
 	}
 
 	rw, req, err := sc.newWriterAndRequest(st, f)
@@ -2120,7 +1996,7 @@ func (sc *serverConn) upgradeRequest(req *http.Request) {
 	sc.serveG.check()
 	id := uint32(1)
 	sc.maxClientStreamID = id
-	st := sc.newStream(id, 0, stateHalfClosedRemote)
+	st := sc.newStream(id, 0, stateHalfClosedRemote, defaultRFC9218Priority(sc.priorityAware && !sc.hasIntermediary))
 	st.reqTrailer = req.Trailer
 	if st.reqTrailer != nil {
 		st.trailer = make(http.Header)
@@ -2185,11 +2061,32 @@ func (sc *serverConn) processPriority(f *PriorityFrame) error {
 	if err := sc.checkPriority(f.StreamID, f.PriorityParam); err != nil {
 		return err
 	}
+	// We need to avoid calling AdjustStream when using the RFC 9218 write
+	// scheduler. Otherwise, incremental's zero value in PriorityParam will
+	// unexpectedly make all streams non-incremental. This causes us to process
+	// streams one-by-one to completion rather than doing it in a round-robin
+	// manner (the historical behavior), which might be unexpected to users.
+	if sc.writeSchedIgnoresRFC7540() {
+		return nil
+	}
 	sc.writeSched.AdjustStream(f.StreamID, f.PriorityParam)
 	return nil
 }
 
-func (sc *serverConn) newStream(id, pusherID uint32, state streamState) *stream {
+func (sc *serverConn) processPriorityUpdate(f *PriorityUpdateFrame) error {
+	sc.priorityAware = true
+	if _, ok := sc.writeSched.(*priorityWriteSchedulerRFC9218); !ok {
+		return nil
+	}
+	p, ok := parseRFC9218Priority(f.Priority, sc.priorityAware)
+	if !ok {
+		return sc.countError("unparsable_priority_update", streamError(f.PrioritizedStreamID, ErrCodeProtocol))
+	}
+	sc.writeSched.AdjustStream(f.PrioritizedStreamID, p)
+	return nil
+}
+
+func (sc *serverConn) newStream(id, pusherID uint32, state streamState, priority PriorityParam) *stream {
 	sc.serveG.check()
 	if id == 0 {
 		panic("internal error: cannot create stream with id 0")
@@ -2212,7 +2109,7 @@ func (sc *serverConn) newStream(id, pusherID uint32, state streamState) *stream
 	}
 
 	sc.streams[id] = st
-	sc.writeSched.OpenStream(st.id, OpenStreamOptions{PusherID: pusherID})
+	sc.writeSched.OpenStream(st.id, OpenStreamOptions{PusherID: pusherID, priority: priority})
 	if st.isPushed() {
 		sc.curPushedStreams++
 	} else {
@@ -2760,21 +2657,6 @@ func (rws *responseWriterState) writeChunk(p []byte) (n int, err error) {
 	return len(p), nil
 }
 
-// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
-// that, if present, signals that the map entry is actually for
-// the response trailers, and not the response headers. The prefix
-// is stripped after the ServeHTTP call finishes and the values are
-// sent in the trailers.
-//
-// This mechanism is intended only for trailers that are not known
-// prior to the headers being written. If the set of trailers is fixed
-// or known before the header is written, the normal Go trailers mechanism
-// is preferred:
-//
-//	https://golang.org/pkg/net/http/#ResponseWriter
-//	https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
-const TrailerPrefix = "Trailer:"
-
 // promoteUndeclaredTrailers permits http.Handlers to set trailers
 // after the header has already been flushed. Because the Go
 // ResponseWriter interface has no way to set Trailers (only the
@@ -3051,12 +2933,6 @@ func (w *responseWriter) handlerDone() {
 	responseWriterStatePool.Put(rws)
 }
 
-// Push errors.
-var (
-	ErrRecursivePush    = errors.New("http2: recursive push not allowed")
-	ErrPushLimitReached = errors.New("http2: push would exceed peer's SETTINGS_MAX_CONCURRENT_STREAMS")
-)
-
 var _ http.Pusher = (*responseWriter)(nil)
 
 func (w *responseWriter) Push(target string, opts *http.PushOptions) error {
@@ -3218,7 +3094,7 @@ func (sc *serverConn) startPush(msg *startPushRequest) {
 		// transition to "half closed (remote)" after sending the initial HEADERS, but
 		// we start in "half closed (remote)" for simplicity.
 		// See further comments at the definition of stateHalfClosedRemote.
-		promised := sc.newStream(promisedID, msg.parent.id, stateHalfClosedRemote)
+		promised := sc.newStream(promisedID, msg.parent.id, stateHalfClosedRemote, defaultRFC9218Priority(sc.priorityAware && !sc.hasIntermediary))
 		rw, req, err := sc.newWriterAndRequestNoBody(promised, httpcommon.ServerRequestParam{
 			Method:    msg.method,
 			Scheme:    msg.url.Scheme,

vendor/golang.org/x/net/http2/server_common.go

@@ -0,0 +1,221 @@
+// Copyright 2026 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 (
+	"context"
+	"errors"
+	"net"
+	"net/http"
+	"time"
+)
+
+// TrailerPrefix is a magic prefix for ResponseWriter.Header map keys
+// that, if present, signals that the map entry is actually for
+// the response trailers, and not the response headers. The prefix
+// is stripped after the ServeHTTP call finishes and the values are
+// sent in the trailers.
+//
+// This mechanism is intended only for trailers that are not known
+// prior to the headers being written. If the set of trailers is fixed
+// or known before the header is written, the normal Go trailers mechanism
+// is preferred:
+//
+//	https://golang.org/pkg/net/http/#ResponseWriter
+//	https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
+const TrailerPrefix = "Trailer:"
+
+// Push errors.
+var (
+	ErrRecursivePush    = errors.New("http2: recursive push not allowed")
+	ErrPushLimitReached = errors.New("http2: push would exceed peer's SETTINGS_MAX_CONCURRENT_STREAMS")
+)
+
+// ConfigureServer adds HTTP/2 support to a net/http Server.
+//
+// The configuration conf may be nil.
+//
+// ConfigureServer must be called before s begins serving.
+func ConfigureServer(s *http.Server, conf *Server) error {
+	return configureServer(s, conf)
+}
+
+// Server is an HTTP/2 server.
+type Server struct {
+	// MaxHandlers limits the number of http.Handler ServeHTTP goroutines
+	// which may run at a time over all connections.
+	// Negative or zero no limit.
+	// TODO: implement
+	MaxHandlers int
+
+	// MaxConcurrentStreams optionally specifies the number of
+	// concurrent streams that each client may have open at a
+	// time. This is unrelated to the number of http.Handler goroutines
+	// which may be active globally, which is MaxHandlers.
+	// If zero, MaxConcurrentStreams defaults to at least 100, per
+	// the HTTP/2 spec's recommendations.
+	MaxConcurrentStreams uint32
+
+	// MaxDecoderHeaderTableSize optionally specifies the http2
+	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
+	// informs the remote endpoint of the maximum size of the header compression
+	// table used to decode header blocks, in octets. If zero, the default value
+	// of 4096 is used.
+	MaxDecoderHeaderTableSize uint32
+
+	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
+	// header compression table used for encoding request headers. Received
+	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
+	// the default value of 4096 is used.
+	MaxEncoderHeaderTableSize uint32
+
+	// MaxReadFrameSize optionally specifies the largest frame
+	// this server is willing to read. A valid value is between
+	// 16k and 16M, inclusive. If zero or otherwise invalid, a
+	// default value is used.
+	MaxReadFrameSize uint32
+
+	// PermitProhibitedCipherSuites, if true, permits the use of
+	// cipher suites prohibited by the HTTP/2 spec.
+	PermitProhibitedCipherSuites bool
+
+	// IdleTimeout specifies how long until idle clients should be
+	// closed with a GOAWAY frame. PING frames are not considered
+	// activity for the purposes of IdleTimeout.
+	// If zero or negative, there is no timeout.
+	IdleTimeout time.Duration
+
+	// ReadIdleTimeout is the timeout after which a health check using a ping
+	// frame will be carried out if no frame is received on the connection.
+	// If zero, no health check is performed.
+	ReadIdleTimeout time.Duration
+
+	// PingTimeout is the timeout after which the connection will be closed
+	// if a response to a ping is not received.
+	// If zero, a default of 15 seconds is used.
+	PingTimeout time.Duration
+
+	// WriteByteTimeout is the timeout after which a connection will be
+	// closed if no data can be written to it. The timeout begins when data is
+	// available to write, and is extended whenever any bytes are written.
+	// If zero or negative, there is no timeout.
+	WriteByteTimeout time.Duration
+
+	// MaxUploadBufferPerConnection is the size of the initial flow
+	// control window for each connections. The HTTP/2 spec does not
+	// allow this to be smaller than 65535 or larger than 2^32-1.
+	// If the value is outside this range, a default value will be
+	// used instead.
+	MaxUploadBufferPerConnection int32
+
+	// MaxUploadBufferPerStream is the size of the initial flow control
+	// window for each stream. The HTTP/2 spec does not allow this to
+	// be larger than 2^32-1. If the value is zero or larger than the
+	// maximum, a default value will be used instead.
+	MaxUploadBufferPerStream int32
+
+	// NewWriteScheduler constructs a write scheduler for a connection.
+	// If nil, a default scheduler is chosen.
+	//
+	// Deprecated: User-provided write schedulers are deprecated.
+	NewWriteScheduler func() WriteScheduler
+
+	// CountError, if non-nil, is called on HTTP/2 server errors.
+	// It's intended to increment a metric for monitoring, such
+	// as an expvar or Prometheus metric.
+	// The errType consists of only ASCII word characters.
+	CountError func(errType string)
+
+	// Internal state. This is a pointer (rather than embedded directly)
+	// so that we don't embed a Mutex in this struct, which will make the
+	// struct non-copyable, which might break some callers.
+	state *serverInternalState
+}
+
+// ServeConnOpts are options for the Server.ServeConn method.
+type ServeConnOpts struct {
+	// Context is the base context to use.
+	// If nil, context.Background is used.
+	Context context.Context
+
+	// BaseConfig optionally sets the base configuration
+	// for values. If nil, defaults are used.
+	BaseConfig *http.Server
+
+	// Handler specifies which handler to use for processing
+	// requests. If nil, BaseConfig.Handler is used. If BaseConfig
+	// or BaseConfig.Handler is nil, http.DefaultServeMux is used.
+	Handler http.Handler
+
+	// UpgradeRequest is an initial request received on a connection
+	// undergoing an h2c upgrade. The request body must have been
+	// completely read from the connection before calling ServeConn,
+	// and the 101 Switching Protocols response written.
+	UpgradeRequest *http.Request
+
+	// Settings is the decoded contents of the HTTP2-Settings header
+	// in an h2c upgrade request.
+	Settings []byte
+
+	// SawClientPreface is set if the HTTP/2 connection preface
+	// has already been read from the connection.
+	SawClientPreface bool
+}
+
+// ServeConn serves HTTP/2 requests on the provided connection and
+// blocks until the connection is no longer readable.
+//
+// ServeConn starts speaking HTTP/2 assuming that c has not had any
+// reads or writes. It writes its initial settings frame and expects
+// to be able to read the preface and settings frame from the
+// client. If c has a ConnectionState method like a *tls.Conn, the
+// ConnectionState is used to verify the TLS ciphersuite and to set
+// the Request.TLS field in Handlers.
+//
+// ServeConn does not support h2c by itself. Any h2c support must be
+// implemented in terms of providing a suitably-behaving net.Conn.
+//
+// The opts parameter is optional. If nil, default values are used.
+func (s *Server) ServeConn(c net.Conn, opts *ServeConnOpts) {
+	if opts == nil {
+		opts = &ServeConnOpts{}
+	}
+	s.serveConn(c, opts, nil)
+}
+
+func (o *ServeConnOpts) context() context.Context {
+	if o != nil && o.Context != nil {
+		return o.Context
+	}
+	return context.Background()
+}
+
+func (o *ServeConnOpts) baseConfig() *http.Server {
+	if o != nil && o.BaseConfig != nil {
+		return o.BaseConfig
+	}
+	return new(http.Server)
+}
+
+func (o *ServeConnOpts) handler() http.Handler {
+	if o != nil {
+		if o.Handler != nil {
+			return o.Handler
+		}
+		if o.BaseConfig != nil && o.BaseConfig.Handler != nil {
+			return o.BaseConfig.Handler
+		}
+	}
+	return http.DefaultServeMux
+}
+
+func serverConnBaseContext(c net.Conn, opts *ServeConnOpts) (ctx context.Context, cancel func()) {
+	ctx, cancel = context.WithCancel(opts.context())
+	ctx = context.WithValue(ctx, http.LocalAddrContextKey, c.LocalAddr())
+	if hs := opts.baseConfig(); hs != nil {
+		ctx = context.WithValue(ctx, http.ServerContextKey, hs)
+	}
+	return
+}

vendor/golang.org/x/net/http2/server_wrap.go

@@ -0,0 +1,201 @@
+// Copyright 2026 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.
+
+//go:build go1.27 && !http2legacy
+
+// Server wrapping a net/http.Server.
+
+package http2
+
+import (
+	"context"
+	"errors"
+	"net"
+	"net/http"
+	"sync"
+	"time"
+)
+
+type serverInternalState struct {
+	s1            *http.Server
+	initOnce      sync.Once
+	serveConnFunc func(context.Context, net.Conn, http.Handler, bool, *http.Request, []byte)
+}
+
+func configureServer(s *http.Server, conf *Server) error {
+	if s == nil {
+		panic("nil *http.Server")
+	}
+	if conf == nil {
+		conf = new(Server)
+	}
+	if conf.state != nil {
+		// This isn't a panic in the pre-wrapping implementation,
+		// but calling ConfigureServer twice with the same http2.Server
+		// overwrites internal state on the server.
+		// Make the error explicit and early here.
+		panic("ConfigureServer may be called only once per Server")
+	}
+	if h1, h2 := s, conf; h2.IdleTimeout == 0 {
+		if h1.IdleTimeout != 0 {
+			h2.IdleTimeout = h1.IdleTimeout
+		} else {
+			h2.IdleTimeout = h1.ReadTimeout
+		}
+	}
+	conf.state = &serverInternalState{
+		s1: s,
+	}
+	sconfig := &serverConfig{s: conf}
+	if err := s.Serve(sconfig); err != nil || sconfig.serveConnFunc == nil {
+		panic("http2: net/http does not support this version of x/net/http2")
+	}
+	conf.state.serveConnFunc = sconfig.serveConnFunc
+	return nil
+}
+
+type serverConfig struct {
+	s             *Server
+	serveConnFunc func(context.Context, net.Conn, http.Handler, bool, *http.Request, []byte)
+}
+
+func (*serverConfig) Accept() (net.Conn, error) {
+	return nil, errors.New("unexpected call to Accept")
+}
+func (*serverConfig) Close() error {
+	return nil
+}
+func (*serverConfig) Addr() net.Addr {
+	return nil
+}
+
+func (s *serverConfig) ServeConnFunc(f func(context.Context, net.Conn, http.Handler, bool, *http.Request, []byte)) {
+	s.serveConnFunc = f
+}
+
+func (s *serverConfig) HTTP2Config() http.HTTP2Config {
+	return http.HTTP2Config{
+		MaxConcurrentStreams:          int(s.s.MaxConcurrentStreams),
+		MaxDecoderHeaderTableSize:     int(s.s.MaxDecoderHeaderTableSize),
+		MaxEncoderHeaderTableSize:     int(s.s.MaxEncoderHeaderTableSize),
+		MaxReadFrameSize:              int(s.s.MaxReadFrameSize),
+		PermitProhibitedCipherSuites:  s.s.PermitProhibitedCipherSuites,
+		MaxReceiveBufferPerConnection: int(s.s.MaxUploadBufferPerConnection),
+		MaxReceiveBufferPerStream:     int(s.s.MaxUploadBufferPerStream),
+		SendPingTimeout:               s.s.ReadIdleTimeout,
+		PingTimeout:                   s.s.PingTimeout,
+		WriteByteTimeout:              s.s.WriteByteTimeout,
+		CountError:                    s.s.CountError,
+	}
+}
+
+func (s *serverConfig) IdleTimeout() time.Duration {
+	return s.s.IdleTimeout
+}
+
+type serverConn struct{}
+
+func (s *Server) serveConn(c net.Conn, opts *ServeConnOpts, _ func(*serverConn)) {
+	var serveConnFunc func(context.Context, net.Conn, http.Handler, bool, *http.Request, []byte)
+	switch {
+	case opts.BaseConfig != nil:
+		// The user has provided us with an http.Server to take configuration from.
+		//
+		// We can't send our request to opts.BaseConfig, because an http.Server can
+		// only be associated with a single http2.Server and the user might
+		// use this one with several http.Servers.
+		//
+		// We can't send our request to s.state.s1, because it doesn't contain
+		// the right configuration.
+		//
+		// So create a one-off copy of opts.BaseConfig and use it.
+		h1 := &http.Server{
+			TLSConfig:         opts.BaseConfig.TLSConfig,
+			ReadTimeout:       opts.BaseConfig.ReadTimeout,
+			ReadHeaderTimeout: opts.BaseConfig.ReadHeaderTimeout,
+			WriteTimeout:      opts.BaseConfig.WriteTimeout,
+			IdleTimeout:       opts.BaseConfig.IdleTimeout,
+			MaxHeaderBytes:    opts.BaseConfig.MaxHeaderBytes,
+			ConnState:         opts.BaseConfig.ConnState,
+			ErrorLog:          opts.BaseConfig.ErrorLog,
+			BaseContext:       opts.BaseConfig.BaseContext,
+			ConnContext:       opts.BaseConfig.ConnContext,
+			HTTP2:             opts.BaseConfig.HTTP2,
+		}
+		sconfig := &serverConfig{s: s}
+		if err := h1.Serve(sconfig); err != nil || sconfig.serveConnFunc == nil {
+			panic("http2: net/http does not support this version of x/net/http2")
+		}
+		serveConnFunc = sconfig.serveConnFunc
+	case s.state != nil:
+		serveConnFunc = s.state.serveConnFunc
+	default:
+		// Strange-but-true: Server has no concurrency-safe way to initialize
+		// its internal state, so historically ServeConn just doesn't use any
+		// persistent state if you don't call ConfigureServer first.
+		//
+		// If ConfigureServer hasn't been called, create a one-off http.Server
+		// for the connection, since we don't have any way to keep one around for reuse.
+		h1 := &http.Server{}
+		sconfig := &serverConfig{s: s}
+		if err := h1.Serve(sconfig); err != nil || sconfig.serveConnFunc == nil {
+			panic("http2: net/http does not support this version of x/net/http2")
+		}
+		serveConnFunc = sconfig.serveConnFunc
+	}
+
+	ctx, cancel := serverConnBaseContext(c, opts)
+	defer cancel()
+	serveConnFunc(ctx, c, opts.handler(), opts.SawClientPreface, opts.UpgradeRequest, opts.Settings)
+
+}
+
+// FrameWriteRequest is a request to write a frame.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+type FrameWriteRequest struct {
+	// Ideally we'd define this in writesched_common.go,
+	// to avoid duplicating an exported symbol across two files,
+	// but the changes required to make this work are fairly large.
+}
+
+func (wr FrameWriteRequest) StreamID() uint32 {
+	return 0
+}
+
+func (wr FrameWriteRequest) DataSize() int {
+	return 0
+}
+
+func (wr FrameWriteRequest) Consume(n int32) (FrameWriteRequest, FrameWriteRequest, int) {
+	return FrameWriteRequest{}, FrameWriteRequest{}, 0
+}
+
+func (wr FrameWriteRequest) String() string {
+	return ""
+}
+
+// NewPriorityWriteScheduler is deprecated.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+func NewPriorityWriteScheduler(cfg *PriorityWriteSchedulerConfig) WriteScheduler {
+	return unsupportedWriteScheduler{}
+}
+
+// NewRandomWriteScheduler is deprecated.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+func NewRandomWriteScheduler() WriteScheduler {
+	return unsupportedWriteScheduler{}
+}
+
+type unsupportedWriteScheduler struct{}
+
+func (unsupportedWriteScheduler) OpenStream(streamID uint32, options OpenStreamOptions) {}
+func (unsupportedWriteScheduler) CloseStream(streamID uint32)                           {}
+func (unsupportedWriteScheduler) AdjustStream(streamID uint32, priority PriorityParam)  {}
+func (unsupportedWriteScheduler) Push(wr FrameWriteRequest)                             {}
+func (unsupportedWriteScheduler) Pop() (wr FrameWriteRequest, ok bool) {
+	return FrameWriteRequest{}, false
+}

vendor/golang.org/x/net/http2/transport.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 // Transport code.
 
 package http2
@@ -21,20 +23,17 @@ import (
 	"log"
 	"math"
 	"math/bits"
-	mathrand "math/rand"
 	"net"
 	"net/http"
 	"net/http/httptrace"
 	"net/textproto"
 	"strconv"
-	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/http/httpguts"
 	"golang.org/x/net/http2/hpack"
-	"golang.org/x/net/idna"
 	"golang.org/x/net/internal/httpcommon"
 )
 
@@ -60,123 +59,7 @@ const (
 	defaultMaxConcurrentStreams = 1000
 )
 
-// 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 {
-	// DialTLSContext specifies an optional dial function with context for
-	// creating TLS connections for requests.
-	//
-	// If DialTLSContext and 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.
-	DialTLSContext func(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error)
-
-	// DialTLS specifies an optional dial function for creating
-	// TLS connections for requests.
-	//
-	// If DialTLSContext and DialTLS is nil, tls.Dial is used.
-	//
-	// Deprecated: Use DialTLSContext instead, which allows the transport
-	// to cancel dials as soon as they are no longer needed.
-	// If both are set, DialTLSContext takes priority.
-	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 allowed. Unlike the http2 spec, zero here
-	// means to use a default limit (currently 10MB). If you actually
-	// want to advertise an unlimited value to the peer, Transport
-	// interprets the highest possible value here (0xffffffff or 1<<32-1)
-	// to mean no limit.
-	MaxHeaderListSize uint32
-
-	// MaxReadFrameSize is the http2 SETTINGS_MAX_FRAME_SIZE to send in the
-	// initial settings frame. It is the size in bytes of the largest frame
-	// payload that the sender is willing to receive. If 0, no setting is
-	// sent, and the value is provided by the peer, which should be 16384
-	// according to the spec:
-	// https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2.
-	// Values are bounded in the range 16k to 16M.
-	MaxReadFrameSize uint32
-
-	// MaxDecoderHeaderTableSize optionally specifies the http2
-	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
-	// informs the remote endpoint of the maximum size of the header compression
-	// table used to decode header blocks, in octets. If zero, the default value
-	// of 4096 is used.
-	MaxDecoderHeaderTableSize uint32
-
-	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
-	// header compression table used for encoding request headers. Received
-	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
-	// the default value of 4096 is used.
-	MaxEncoderHeaderTableSize uint32
-
-	// StrictMaxConcurrentStreams controls whether the server's
-	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
-	// globally. If false, new TCP connections are created to the
-	// server as needed to keep each under the per-connection
-	// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
-	// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
-	// a global limit and callers of RoundTrip block when needed,
-	// waiting for their turn.
-	StrictMaxConcurrentStreams bool
-
-	// IdleConnTimeout is the maximum amount of time an idle
-	// (keep-alive) connection will remain idle before closing
-	// itself.
-	// Zero means no limit.
-	IdleConnTimeout time.Duration
-
-	// ReadIdleTimeout is the timeout after which a health check using ping
-	// frame will be carried out if no frame is received on the connection.
-	// Note that a ping response will is considered a received frame, so if
-	// there is no other traffic on the connection, the health check will
-	// be performed every ReadIdleTimeout interval.
-	// If zero, no health check is performed.
-	ReadIdleTimeout time.Duration
-
-	// PingTimeout is the timeout after which the connection will be closed
-	// if a response to Ping is not received.
-	// Defaults to 15s.
-	PingTimeout time.Duration
-
-	// WriteByteTimeout is the timeout after which the connection will be
-	// closed no data can be written to it. The timeout begins when data is
-	// available to write, and is extended whenever any bytes are written.
-	WriteByteTimeout time.Duration
-
-	// CountError, if non-nil, is called on HTTP/2 transport errors.
-	// It's intended to increment a metric for monitoring, such
-	// as an expvar or Prometheus metric.
-	// The errType consists of only ASCII word characters.
-	CountError func(errType string)
-
+type transportInternal struct {
 	// t1, if non-nil, is the standard library Transport using
 	// this transport. Its settings are used (but not its
 	// RoundTrip method, etc).
@@ -217,27 +100,18 @@ func (t *Transport) disableCompression() bool {
 	return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
 }
 
-// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
-// It returns an error if t1 has already been HTTP/2-enabled.
-//
-// Use ConfigureTransports instead to configure the HTTP/2 Transport.
-func ConfigureTransport(t1 *http.Transport) error {
-	_, err := ConfigureTransports(t1)
+func configureTransport(t1 *http.Transport) error {
+	_, err := configureTransports(t1)
 	return err
 }
 
-// ConfigureTransports configures a net/http HTTP/1 Transport to use HTTP/2.
-// It returns a new HTTP/2 Transport for further configuration.
-// It returns an error if t1 has already been HTTP/2-enabled.
-func ConfigureTransports(t1 *http.Transport) (*Transport, error) {
-	return configureTransports(t1)
-}
-
 func configureTransports(t1 *http.Transport) (*Transport, error) {
 	connPool := new(clientConnPool)
 	t2 := &Transport{
 		ConnPool: noDialClientConnPool{connPool},
-		t1:       t1,
+		transportInternal: transportInternal{
+			t1: t1,
+		},
 	}
 	connPool.t = t2
 	if err := registerHTTPSProtocol(t1, noDialH2RoundTripper{t2}); err != nil {
@@ -525,68 +399,7 @@ func (sew stickyErrWriter) Write(p []byte) (n int, err error) {
 	return n, err
 }
 
-// noCachedConnError is the concrete type of ErrNoCachedConn, which
-// needs to be detected by net/http regardless of whether it's its
-// bundled version (in h2_bundle.go with a rewritten type name) or
-// from a user's x/net/http2. As such, as it has a unique method name
-// (IsHTTP2NoCachedConnError) that net/http sniffs for via func
-// isNoCachedConnError.
-type noCachedConnError struct{}
-
-func (noCachedConnError) IsHTTP2NoCachedConnError() {}
-func (noCachedConnError) Error() string             { return "http2: no cached connection was available" }
-
-// isNoCachedConnError reports whether err is of type noCachedConnError
-// or its equivalent renamed type in net/http2's h2_bundle.go. Both types
-// may coexist in the same running program.
-func isNoCachedConnError(err error) bool {
-	_, ok := err.(interface{ IsHTTP2NoCachedConnError() })
-	return ok
-}
-
-var ErrNoCachedConn error = noCachedConnError{}
-
-// 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
-
-	allowHTTP bool // allow http:// URLs
-}
-
-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
-		host = authority
-		port = ""
-	}
-	if port == "" { // authority's port was empty
-		port = "443"
-		if scheme == "http" {
-			port = "80"
-		}
-	}
-	if a, err := idna.ToASCII(host); err == nil {
-		host = a
-	}
-	// IPv6 address literal, without a port:
-	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
-		return host + ":" + port
-	}
-	return net.JoinHostPort(host, port)
-}
-
-// RoundTripOpt is like RoundTrip, but takes options.
-func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) {
+func (t *Transport) roundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) {
 	switch req.URL.Scheme {
 	case "https":
 		// Always okay.
@@ -597,134 +410,16 @@ func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Res
 	default:
 		return nil, errors.New("http2: unsupported scheme")
 	}
-
-	addr := authorityAddr(req.URL.Scheme, req.URL.Host)
-	for retry := 0; ; retry++ {
-		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
-		}
-		reused := !atomic.CompareAndSwapUint32(&cc.atomicReused, 0, 1)
-		traceGotConn(req, cc, reused)
-		res, err := cc.RoundTrip(req)
-		if err != nil && retry <= 6 {
-			roundTripErr := err
-			if req, err = shouldRetryRequest(req, err); err == nil {
-				// After the first retry, do exponential backoff with 10% jitter.
-				if retry == 0 {
-					t.vlogf("RoundTrip retrying after failure: %v", roundTripErr)
-					continue
-				}
-				backoff := float64(uint(1) << (uint(retry) - 1))
-				backoff += backoff * (0.1 * mathrand.Float64())
-				d := time.Second * time.Duration(backoff)
-				tm := time.NewTimer(d)
-				select {
-				case <-tm.C:
-					t.vlogf("RoundTrip retrying after failure: %v", roundTripErr)
-					continue
-				case <-req.Context().Done():
-					tm.Stop()
-					err = req.Context().Err()
-				}
-			}
-		}
-		if err == errClientConnNotEstablished {
-			// This ClientConn was created recently,
-			// this is the first request to use it,
-			// and the connection is closed and not usable.
-			//
-			// In this state, cc.idleTimer will remove the conn from the pool
-			// when it fires. Stop the timer and remove it here so future requests
-			// won't try to use this connection.
-			//
-			// If the timer has already fired and we're racing it, the redundant
-			// call to MarkDead is harmless.
-			if cc.idleTimer != nil {
-				cc.idleTimer.Stop()
-			}
-			t.connPool().MarkDead(cc)
-		}
-		if err != nil {
-			t.vlogf("RoundTrip failure: %v", err)
-			return nil, err
-		}
-		return res, nil
-	}
+	return t.roundTripViaPool(req, opt, t.connPool())
 }
 
-// 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() {
+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")
-	errClientConnNotEstablished = errors.New("http2: client conn could not be established")
-	errClientConnGotGoAway      = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
-	errClientConnForceClosed    = errors.New("http2: client connection force closed via ClientConn.Close")
-)
-
-// 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) {
-	if !canRetryError(err) {
-		return nil, err
-	}
-	// If the Body is nil (or http.NoBody), it's safe to reuse
-	// this request and its Body.
-	if req.Body == nil || req.Body == http.NoBody {
-		return req, nil
-	}
-
-	// If the request body can be reset back to its original
-	// state via the optional req.GetBody, do that.
-	if req.GetBody != nil {
-		body, err := req.GetBody()
-		if err != nil {
-			return nil, err
-		}
-		newReq := *req
-		newReq.Body = body
-		return &newReq, nil
-	}
-
-	// The Request.Body can't reset back to the beginning, but we
-	// don't seem to have started to read from it yet, so reuse
-	// the request directly.
-	if err == errClientConnUnusable {
-		return req, nil
-	}
-
-	return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err)
-}
-
-func canRetryError(err error) bool {
-	if err == errClientConnUnusable || err == errClientConnGotGoAway {
-		return true
-	}
-	if se, ok := err.(StreamError); ok {
-		if se.Code == ErrCodeProtocol && se.Cause == errFromPeer {
-			// See golang/go#47635, golang/go#42777
-			return true
-		}
-		return se.Code == ErrCodeRefusedStream
-	}
-	return false
-}
-
 func (t *Transport) dialClientConn(ctx context.Context, addr string, singleUse bool) (*ClientConn, error) {
-	if t.transportTestHooks != nil {
-		return t.newClientConn(nil, singleUse, nil)
-	}
 	host, _, err := net.SplitHostPort(addr)
 	if err != nil {
 		return nil, err
@@ -750,27 +445,6 @@ func (t *Transport) newTLSConfig(host string) *tls.Config {
 	return cfg
 }
 
-func (t *Transport) dialTLS(ctx context.Context, network, addr string, tlsCfg *tls.Config) (net.Conn, error) {
-	if t.DialTLSContext != nil {
-		return t.DialTLSContext(ctx, network, addr, tlsCfg)
-	} else if t.DialTLS != nil {
-		return t.DialTLS(network, addr, tlsCfg)
-	}
-
-	tlsCn, err := t.dialTLSWithContext(ctx, network, addr, tlsCfg)
-	if err != nil {
-		return nil, err
-	}
-	state := tlsCn.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 tlsCn, nil
-}
-
 // disableKeepAlives reports whether connections should be closed as
 // soon as possible after handling the first request.
 func (t *Transport) disableKeepAlives() bool {
@@ -784,7 +458,7 @@ func (t *Transport) expectContinueTimeout() time.Duration {
 	return t.t1.ExpectContinueTimeout
 }
 
-func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
+func (t *Transport) newUserClientConn(c net.Conn) (*ClientConn, error) {
 	return t.newClientConn(c, t.disableKeepAlives(), nil)
 }
 
@@ -897,8 +571,7 @@ func (cc *ClientConn) healthCheck() {
 	}
 }
 
-// SetDoNotReuse marks cc as not reusable for future HTTP requests.
-func (cc *ClientConn) SetDoNotReuse() {
+func (cc *ClientConn) setDoNotReuse() {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
 	cc.doNotReuse = true
@@ -939,21 +612,13 @@ func (cc *ClientConn) setGoAway(f *GoAwayFrame) {
 	}
 }
 
-// CanTakeNewRequest reports whether the connection can take a new request,
-// meaning it has not been closed or received or sent a GOAWAY.
-//
-// If the caller is going to immediately make a new request on this
-// connection, use ReserveNewRequest instead.
-func (cc *ClientConn) CanTakeNewRequest() bool {
+func (cc *ClientConn) canTakeNewRequest() bool {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
 	return cc.canTakeNewRequestLocked()
 }
 
-// ReserveNewRequest is like CanTakeNewRequest but also reserves a
-// concurrent stream in cc. The reservation is decremented on the
-// next call to RoundTrip.
-func (cc *ClientConn) ReserveNewRequest() bool {
+func (cc *ClientConn) reserveNewRequest() bool {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
 	if st := cc.idleStateLocked(); !st.canTakeNewRequest {
@@ -963,41 +628,7 @@ func (cc *ClientConn) ReserveNewRequest() bool {
 	return true
 }
 
-// ClientConnState describes the state of a ClientConn.
-type ClientConnState struct {
-	// Closed is whether the connection is closed.
-	Closed bool
-
-	// Closing is whether the connection is in the process of
-	// closing. It may be closing due to shutdown, being a
-	// single-use connection, being marked as DoNotReuse, or
-	// having received a GOAWAY frame.
-	Closing bool
-
-	// StreamsActive is how many streams are active.
-	StreamsActive int
-
-	// StreamsReserved is how many streams have been reserved via
-	// ClientConn.ReserveNewRequest.
-	StreamsReserved int
-
-	// StreamsPending is how many requests have been sent in excess
-	// of the peer's advertised MaxConcurrentStreams setting and
-	// are waiting for other streams to complete.
-	StreamsPending int
-
-	// MaxConcurrentStreams is how many concurrent streams the
-	// peer advertised as acceptable. Zero means no SETTINGS
-	// frame has been received yet.
-	MaxConcurrentStreams uint32
-
-	// LastIdle, if non-zero, is when the connection last
-	// transitioned to idle state.
-	LastIdle time.Time
-}
-
-// State returns a snapshot of cc's state.
-func (cc *ClientConn) State() ClientConnState {
+func (cc *ClientConn) state() ClientConnState {
 	cc.wmu.Lock()
 	maxConcurrent := cc.maxConcurrentStreams
 	if !cc.seenSettings {
@@ -1168,6 +799,12 @@ func (cc *ClientConn) closeIfIdle() {
 	cc.closeConn()
 }
 
+func (cc *ClientConn) stopIdleTimer() {
+	if cc.idleTimer != nil {
+		cc.idleTimer.Stop()
+	}
+}
+
 func (cc *ClientConn) isDoNotReuseAndIdle() bool {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
@@ -1176,8 +813,7 @@ func (cc *ClientConn) isDoNotReuseAndIdle() bool {
 
 var shutdownEnterWaitStateHook = func() {}
 
-// Shutdown gracefully closes the client connection, waiting for running streams to complete.
-func (cc *ClientConn) Shutdown(ctx context.Context) error {
+func (cc *ClientConn) shutdown(ctx context.Context) error {
 	if err := cc.sendGoAway(); err != nil {
 		return err
 	}
@@ -1251,10 +887,7 @@ func (cc *ClientConn) closeForError(err error) {
 	cc.closeConn()
 }
 
-// Close closes the client connection immediately.
-//
-// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
-func (cc *ClientConn) Close() error {
+func (cc *ClientConn) close() error {
 	cc.closeForError(errClientConnForceClosed)
 	return nil
 }
@@ -1308,11 +941,11 @@ func (cc *ClientConn) decrStreamReservationsLocked() {
 	}
 }
 
-func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
-	return cc.roundTrip(req, nil)
+func (cc *ClientConn) roundTrip(req *http.Request) (*http.Response, error) {
+	return cc.internalRoundTrip(req, nil)
 }
 
-func (cc *ClientConn) roundTrip(req *http.Request, streamf func(*clientStream)) (*http.Response, error) {
+func (cc *ClientConn) internalRoundTrip(req *http.Request, streamf func(*clientStream)) (*http.Response, error) {
 	ctx := req.Context()
 	cs := &clientStream{
 		cc:                   cc,
@@ -2132,19 +1765,6 @@ func (cc *ClientConn) readLoop() {
 	}
 }
 
-// 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
@@ -2779,6 +2399,11 @@ func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) {
 	cs.abortStream(err)
 }
 
+func (rl *clientConnReadLoop) endStreamErrorLocked(cs *clientStream, err error) {
+	cs.readAborted = true
+	cs.abortStreamLocked(err)
+}
+
 // Constants passed to streamByID for documentation purposes.
 const (
 	headerOrDataFrame    = true
@@ -2860,6 +2485,9 @@ func (rl *clientConnReadLoop) processSettingsNoWrite(f *SettingsFrame) error {
 
 	var seenMaxConcurrentStreams bool
 	err := f.ForeachSetting(func(s Setting) error {
+		if err := s.Valid(); err != nil {
+			return err
+		}
 		switch s.ID {
 		case SettingMaxFrameSize:
 			cc.maxFrameSize = s.Val
@@ -2891,9 +2519,6 @@ func (rl *clientConnReadLoop) processSettingsNoWrite(f *SettingsFrame) error {
 			cc.henc.SetMaxDynamicTableSize(s.Val)
 			cc.peerMaxHeaderTableSize = s.Val
 		case SettingEnableConnectProtocol:
-			if err := s.Valid(); err != nil {
-				return err
-			}
 			// If the peer wants to send us SETTINGS_ENABLE_CONNECT_PROTOCOL,
 			// we require that it do so in the first SETTINGS frame.
 			//
@@ -2946,7 +2571,7 @@ func (rl *clientConnReadLoop) processWindowUpdate(f *WindowUpdateFrame) error {
 	if !fl.add(int32(f.Increment)) {
 		// For stream, the sender sends RST_STREAM with an error code of FLOW_CONTROL_ERROR
 		if cs != nil {
-			rl.endStreamError(cs, StreamError{
+			rl.endStreamErrorLocked(cs, StreamError{
 				StreamID: f.StreamID,
 				Code:     ErrCodeFlowControl,
 			})
@@ -2980,7 +2605,7 @@ func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error {
 }
 
 // Ping sends a PING frame to the server and waits for the ack.
-func (cc *ClientConn) Ping(ctx context.Context) error {
+func (cc *ClientConn) ping(ctx context.Context) error {
 	c := make(chan struct{})
 	// Generate a random payload
 	var p [8]byte
@@ -3094,16 +2719,6 @@ 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 = noBodyReader{}
 
 type noBodyReader struct{}
@@ -3228,10 +2843,6 @@ 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 }
-
 // isConnectionCloseRequest reports whether req should use its own
 // connection for a single request and then close the connection.
 func isConnectionCloseRequest(req *http.Request) bool {
@@ -3423,17 +3034,3 @@ func traceGot1xxResponseFunc(trace *httptrace.ClientTrace) func(int, textproto.M
 	}
 	return nil
 }
-
-// dialTLSWithContext uses tls.Dialer, added in Go 1.15, to open a TLS
-// connection.
-func (t *Transport) dialTLSWithContext(ctx context.Context, network, addr string, cfg *tls.Config) (*tls.Conn, error) {
-	dialer := &tls.Dialer{
-		Config: cfg,
-	}
-	cn, err := dialer.DialContext(ctx, network, addr)
-	if err != nil {
-		return nil, err
-	}
-	tlsCn := cn.(*tls.Conn) // DialContext comment promises this will always succeed
-	return tlsCn, nil
-}

vendor/golang.org/x/net/http2/transport_common.go

@@ -0,0 +1,447 @@
+// Copyright 2026 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 (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"log"
+	mathrand "math/rand"
+	"net"
+	"net/http"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"golang.org/x/net/idna"
+)
+
+// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
+// It returns an error if t1 has already been HTTP/2-enabled.
+//
+// Use ConfigureTransports instead to configure the HTTP/2 Transport.
+func ConfigureTransport(t1 *http.Transport) error {
+	return configureTransport(t1)
+}
+
+// ConfigureTransports configures a net/http HTTP/1 Transport to use HTTP/2.
+// It returns a new HTTP/2 Transport for further configuration.
+// It returns an error if t1 has already been HTTP/2-enabled.
+func ConfigureTransports(t1 *http.Transport) (*Transport, error) {
+	return configureTransports(t1)
+}
+
+// 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 {
+	// DialTLSContext specifies an optional dial function with context for
+	// creating TLS connections for requests.
+	//
+	// If DialTLSContext and 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.
+	DialTLSContext func(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error)
+
+	// DialTLS specifies an optional dial function for creating
+	// TLS connections for requests.
+	//
+	// If DialTLSContext and DialTLS is nil, tls.Dial is used.
+	//
+	// Deprecated: Use DialTLSContext instead, which allows the transport
+	// to cancel dials as soon as they are no longer needed.
+	// If both are set, DialTLSContext takes priority.
+	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 allowed. Unlike the http2 spec, zero here
+	// means to use a default limit (currently 10MB). If you actually
+	// want to advertise an unlimited value to the peer, Transport
+	// interprets the highest possible value here (0xffffffff or 1<<32-1)
+	// to mean no limit.
+	MaxHeaderListSize uint32
+
+	// MaxReadFrameSize is the http2 SETTINGS_MAX_FRAME_SIZE to send in the
+	// initial settings frame. It is the size in bytes of the largest frame
+	// payload that the sender is willing to receive. If 0, no setting is
+	// sent, and the value is provided by the peer, which should be 16384
+	// according to the spec:
+	// https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2.
+	// Values are bounded in the range 16k to 16M.
+	MaxReadFrameSize uint32
+
+	// MaxDecoderHeaderTableSize optionally specifies the http2
+	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
+	// informs the remote endpoint of the maximum size of the header compression
+	// table used to decode header blocks, in octets. If zero, the default value
+	// of 4096 is used.
+	MaxDecoderHeaderTableSize uint32
+
+	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
+	// header compression table used for encoding request headers. Received
+	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
+	// the default value of 4096 is used.
+	MaxEncoderHeaderTableSize uint32
+
+	// StrictMaxConcurrentStreams controls whether the server's
+	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
+	// globally. If false, new TCP connections are created to the
+	// server as needed to keep each under the per-connection
+	// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
+	// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
+	// a global limit and callers of RoundTrip block when needed,
+	// waiting for their turn.
+	StrictMaxConcurrentStreams bool
+
+	// IdleConnTimeout is the maximum amount of time an idle
+	// (keep-alive) connection will remain idle before closing
+	// itself.
+	// Zero means no limit.
+	IdleConnTimeout time.Duration
+
+	// ReadIdleTimeout is the timeout after which a health check using ping
+	// frame will be carried out if no frame is received on the connection.
+	// Note that a ping response will is considered a received frame, so if
+	// there is no other traffic on the connection, the health check will
+	// be performed every ReadIdleTimeout interval.
+	// If zero, no health check is performed.
+	ReadIdleTimeout time.Duration
+
+	// PingTimeout is the timeout after which the connection will be closed
+	// if a response to Ping is not received.
+	// Defaults to 15s.
+	PingTimeout time.Duration
+
+	// WriteByteTimeout is the timeout after which the connection will be
+	// closed no data can be written to it. The timeout begins when data is
+	// available to write, and is extended whenever any bytes are written.
+	WriteByteTimeout time.Duration
+
+	// CountError, if non-nil, is called on HTTP/2 transport errors.
+	// It's intended to increment a metric for monitoring, such
+	// as an expvar or Prometheus metric.
+	// The errType consists of only ASCII word characters.
+	CountError func(errType string)
+
+	// Internal state, differs between wrapped and non-wrapped implementations.
+	transportInternal
+}
+
+var (
+	errClientConnClosed         = errors.New("http2: client conn is closed")
+	errClientConnNotEstablished = errors.New("http2: client conn could not be established")
+	errClientConnGotGoAway      = errors.New("http2: Transport received Server's graceful shutdown GOAWAY")
+	errClientConnForceClosed    = errors.New("http2: client connection force closed via ClientConn.Close")
+	errClientConnUnusable       = errors.New("http2: client conn not usable")
+)
+
+// ClientConnPool manages a pool of HTTP/2 client connections.
+type ClientConnPool interface {
+	// GetClientConn returns a specific HTTP/2 connection (usually
+	// a TLS-TCP connection) to an HTTP/2 server. On success, the
+	// returned ClientConn accounts for the upcoming RoundTrip
+	// call, so the caller should not omit it. If the caller needs
+	// to, ClientConn.RoundTrip can be called with a bogus
+	// new(http.Request) to release the stream reservation.
+	GetClientConn(req *http.Request, addr string) (*ClientConn, error)
+	MarkDead(*ClientConn)
+}
+
+// ClientConnState describes the state of a ClientConn.
+type ClientConnState struct {
+	// Closed is whether the connection is closed.
+	Closed bool
+
+	// Closing is whether the connection is in the process of
+	// closing. It may be closing due to shutdown, being a
+	// single-use connection, being marked as DoNotReuse, or
+	// having received a GOAWAY frame.
+	Closing bool
+
+	// StreamsActive is how many streams are active.
+	StreamsActive int
+
+	// StreamsReserved is how many streams have been reserved via
+	// ClientConn.ReserveNewRequest.
+	StreamsReserved int
+
+	// StreamsPending is how many requests have been sent in excess
+	// of the peer's advertised MaxConcurrentStreams setting and
+	// are waiting for other streams to complete.
+	StreamsPending int
+
+	// MaxConcurrentStreams is how many concurrent streams the
+	// peer advertised as acceptable. Zero means no SETTINGS
+	// frame has been received yet.
+	MaxConcurrentStreams uint32
+
+	// LastIdle, if non-zero, is when the connection last
+	// transitioned to idle state.
+	LastIdle time.Time
+}
+
+// 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 was broken in https://go.dev/cl/16699.
+	OnlyCachedConn bool
+
+	allowHTTP bool // allow http:// URLs
+}
+
+func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) {
+	return t.RoundTripOpt(req, RoundTripOpt{})
+}
+
+// RoundTripOpt is like RoundTrip, but takes options.
+func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) {
+	return t.roundTripOpt(req, opt)
+}
+
+// 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() {
+	t.closeIdleConnections()
+}
+
+func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
+	return t.newUserClientConn(c)
+}
+
+// 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
+		host = authority
+		port = ""
+	}
+	if port == "" { // authority's port was empty
+		port = "443"
+		if scheme == "http" {
+			port = "80"
+		}
+	}
+	if a, err := idna.ToASCII(host); err == nil {
+		host = a
+	}
+	// IPv6 address literal, without a port:
+	if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") {
+		return host + ":" + port
+	}
+	return net.JoinHostPort(host, port)
+}
+
+func (t *Transport) roundTripViaPool(req *http.Request, opt RoundTripOpt, pool ClientConnPool) (*http.Response, error) {
+	addr := authorityAddr(req.URL.Scheme, req.URL.Host)
+	for retry := 0; ; retry++ {
+		cc, err := pool.GetClientConn(req, addr)
+		if err != nil {
+			t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err)
+			return nil, err
+		}
+		reused := !atomic.CompareAndSwapUint32(&cc.atomicReused, 0, 1)
+		traceGotConn(req, cc, reused)
+		res, err := cc.RoundTrip(req)
+		if err != nil && retry <= 6 {
+			roundTripErr := err
+			if req, err = shouldRetryRequest(req, err); err == nil {
+				// After the first retry, do exponential backoff with 10% jitter.
+				if retry == 0 {
+					t.vlogf("RoundTrip retrying after failure: %v", roundTripErr)
+					continue
+				}
+				backoff := float64(uint(1) << (uint(retry) - 1))
+				backoff += backoff * (0.1 * mathrand.Float64())
+				d := time.Second * time.Duration(backoff)
+				tm := time.NewTimer(d)
+				select {
+				case <-tm.C:
+					t.vlogf("RoundTrip retrying after failure: %v", roundTripErr)
+					continue
+				case <-req.Context().Done():
+					tm.Stop()
+					err = req.Context().Err()
+				}
+			}
+		}
+		if err == errClientConnNotEstablished {
+			// This ClientConn was created recently,
+			// this is the first request to use it,
+			// and the connection is closed and not usable.
+			//
+			// In this state, cc.idleTimer will remove the conn from the pool
+			// when it fires. Stop the timer and remove it here so future requests
+			// won't try to use this connection.
+			//
+			// If the timer has already fired and we're racing it, the redundant
+			// call to MarkDead is harmless.
+			cc.stopIdleTimer()
+			pool.MarkDead(cc)
+		}
+		if err != nil {
+			t.vlogf("RoundTrip failure: %v", err)
+			return nil, err
+		}
+		return res, nil
+	}
+}
+
+// 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) {
+	if !canRetryError(err) {
+		return nil, err
+	}
+	// If the Body is nil (or http.NoBody), it's safe to reuse
+	// this request and its Body.
+	if req.Body == nil || req.Body == http.NoBody {
+		return req, nil
+	}
+
+	// If the request body can be reset back to its original
+	// state via the optional req.GetBody, do that.
+	if req.GetBody != nil {
+		body, err := req.GetBody()
+		if err != nil {
+			return nil, err
+		}
+		newReq := *req
+		newReq.Body = body
+		return &newReq, nil
+	}
+
+	// The Request.Body can't reset back to the beginning, but we
+	// don't seem to have started to read from it yet, so reuse
+	// the request directly.
+	if err == errClientConnUnusable {
+		return req, nil
+	}
+
+	return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err)
+}
+
+func canRetryError(err error) bool {
+	if err == errClientConnUnusable || err == errClientConnGotGoAway {
+		return true
+	}
+	if se, ok := err.(StreamError); ok {
+		return se.Code == ErrCodeRefusedStream
+	}
+	return false
+}
+
+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...)
+}
+
+func (t *Transport) dialTLS(ctx context.Context, network, addr string, tlsCfg *tls.Config) (net.Conn, error) {
+	if t.DialTLSContext != nil {
+		return t.DialTLSContext(ctx, network, addr, tlsCfg)
+	} else if t.DialTLS != nil {
+		return t.DialTLS(network, addr, tlsCfg)
+	}
+
+	tlsCn, err := t.dialTLSWithContext(ctx, network, addr, tlsCfg)
+	if err != nil {
+		return nil, err
+	}
+	state := tlsCn.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 tlsCn, nil
+}
+
+// dialTLSWithContext uses tls.Dialer, added in Go 1.15, to open a TLS
+// connection.
+func (t *Transport) dialTLSWithContext(ctx context.Context, network, addr string, cfg *tls.Config) (*tls.Conn, error) {
+	dialer := &tls.Dialer{
+		Config: cfg,
+	}
+	cn, err := dialer.DialContext(ctx, network, addr)
+	if err != nil {
+		return nil, err
+	}
+	tlsCn := cn.(*tls.Conn) // DialContext comment promises this will always succeed
+	return tlsCn, nil
+}
+
+// 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)
+}
+
+// noCachedConnError is the concrete type of ErrNoCachedConn, which
+// needs to be detected by net/http regardless of whether it's its
+// bundled version (in h2_bundle.go with a rewritten type name) or
+// from a user's x/net/http2. As such, as it has a unique method name
+// (IsHTTP2NoCachedConnError) that net/http sniffs for via func
+// isNoCachedConnError.
+type noCachedConnError struct{}
+
+func (noCachedConnError) IsHTTP2NoCachedConnError() {}
+func (noCachedConnError) Error() string             { return "http2: no cached connection was available" }
+
+// isNoCachedConnError reports whether err is of type noCachedConnError
+// or its equivalent renamed type in net/http2's h2_bundle.go. Both types
+// may coexist in the same running program.
+func isNoCachedConnError(err error) bool {
+	_, ok := err.(interface{ IsHTTP2NoCachedConnError() })
+	return ok
+}
+
+var ErrNoCachedConn error = noCachedConnError{}

vendor/golang.org/x/net/http2/transport_wrap.go

@@ -0,0 +1,381 @@
+// Copyright 2026 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.
+
+//go:build go1.27 && !http2legacy
+
+// Transport wrapping a net/http.Transport.
+
+package http2
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"math"
+	"net"
+	"net/http"
+	"net/http/httptrace"
+	"slices"
+	"sync"
+	"time"
+)
+
+func configureTransport(t1 *http.Transport) error {
+	// ConfigureTransport is a no-op: The http.Transport already supports HTTP/2.
+	return nil
+}
+
+func configureTransports(t1 *http.Transport) (*Transport, error) {
+	// ConfigureTransport returns an http2.Transport with a configuration
+	// linked to the http.Transport's.
+	tr2 := &Transport{}
+	tr2.configure(t1)
+	return tr2, nil
+}
+
+// transportConfig is passed to net/http.Transport.RegisterProtocol("http/2", config).
+// It provides the net/http.Transport with access to the configuration in the
+// x/net/http2.Transport.
+type transportConfig struct {
+	t *Transport
+}
+
+// Registered is called by net/http.Transport.RegisterProtocol,
+// to let us know that it understands the registration mechanism we're using.
+func (t transportConfig) Registered(t1 *http.Transport) {
+	t.t.t1 = t1
+}
+
+func (t transportConfig) DisableCompression() bool {
+	return t.t.DisableCompression
+}
+
+func (t transportConfig) MaxHeaderListSize() int64 {
+	return int64(t.t.MaxHeaderListSize)
+}
+
+func (t transportConfig) IdleConnTimeout() time.Duration {
+	return t.t.IdleConnTimeout
+}
+
+func (t transportConfig) HTTP2Config() http.HTTP2Config {
+	return http.HTTP2Config{
+		StrictMaxConcurrentRequests: t.t.StrictMaxConcurrentStreams,
+		MaxDecoderHeaderTableSize:   int(t.t.MaxDecoderHeaderTableSize),
+		MaxEncoderHeaderTableSize:   int(t.t.MaxEncoderHeaderTableSize),
+		MaxReadFrameSize:            int(t.t.MaxReadFrameSize),
+		SendPingTimeout:             t.t.ReadIdleTimeout,
+		PingTimeout:                 t.t.PingTimeout,
+		WriteByteTimeout:            t.t.WriteByteTimeout,
+		CountError:                  t.t.CountError,
+	}
+}
+
+// ExternalRoundTrip reports whether the Transport wants to take control of the RoundTrip call.
+// If the user hasn't configured a custom connection pool, we leave the RoundTrip up to net/http.
+func (t transportConfig) ExternalRoundTrip() bool {
+	return t.t.ConnPool != nil
+}
+
+// RoundTrip is used when the http.Transport is passing control of the full
+// RoundTrip to us--connection pooling, retries, etc.
+//
+// This is only used when the http2.Transport has a user-provided ConnPool.
+// Any other time, net/http handles everything.
+func (t transportConfig) RoundTrip(req *http.Request) (*http.Response, error) {
+	if t.t.ConnPool == nil {
+		return nil, http.ErrSkipAltProtocol
+	}
+	return t.t.RoundTrip(req)
+}
+
+// netConnContextKey passes a net.Conn to http.Transport.NewClientConn.
+// See http2.Transport.NewClientConn.
+type netConnContextKey struct{}
+
+// ConnFromContext lets the http.Transport fetch a net.Conn out of a context
+// passed to NewClientConn. See http2.Transport.NewClientConn.
+func (t transportConfig) ConnFromContext(ctx context.Context) net.Conn {
+	nc, _ := ctx.Value(netConnContextKey{}).(net.Conn)
+	return nc
+}
+
+// http2TransportContextKey marks a RoundTrip as needing its dial handled by the http2.Transport.
+// We set this for http2.RoundTrip calls, where the historical behavior is to use the
+// http2.Transport's dialer.
+type http2TransportContextKey struct{}
+
+// DialFromContext dials a new connection using the http2.Transport's DialTLS/DialTLSContext.
+func (t transportConfig) DialFromContext(ctx context.Context, network, address string) (net.Conn, error) {
+	if ctx.Value(http2TransportContextKey{}) == nil {
+		// We're being called from a RoundTrip that did not start with an http2.Transport.
+		// Use the http.Transport's dialer.
+		return nil, errors.ErrUnsupported
+	}
+
+	tlsConf := t.t.TLSClientConfig
+	if tlsConf == nil {
+		tlsConf = &tls.Config{}
+	} else {
+		tlsConf = tlsConf.Clone()
+	}
+	if !slices.Contains(tlsConf.NextProtos, "h2") {
+		tlsConf.NextProtos = append([]string{"h2"}, tlsConf.NextProtos...)
+	}
+	if tlsConf.ServerName == "" {
+		host, _, err := net.SplitHostPort(address)
+		if err == nil {
+			tlsConf.ServerName = host
+		}
+	}
+	return t.t.dialTLS(ctx, network, address, tlsConf)
+}
+
+type transportInternal struct {
+	initOnce sync.Once
+	t1       *http.Transport
+}
+
+func (t *Transport) init() {
+	t.initOnce.Do(func() {
+		if t.t1 != nil {
+			return
+		}
+		t1 := &http.Transport{}
+		t.configure(t1)
+	})
+}
+
+func (t *Transport) configure(t1 *http.Transport) {
+	t1.RegisterProtocol("http/2", transportConfig{t})
+	// tr2.t1 is set by transportConfig.Registered.
+	if t.t1 != t1 {
+		panic("http2: net/http does not support this version of x/net/http2")
+	}
+}
+
+func (t *Transport) roundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) {
+	t.init()
+
+	if req.URL.Scheme == "http" && !t.AllowHTTP {
+		return nil, errors.New("http2: unencrypted HTTP/2 not enabled")
+	}
+
+	// When the Transport has a user-provided connection pool (unusual, deprecated),
+	// we need to handle picking a connection, retrys, etc.
+	if t.ConnPool != nil {
+		return t.roundTripViaPool(req, opt, t.ConnPool)
+	}
+
+	// Setting this context key lets net/http know that if it is necessary to dial
+	// a new connection, we should handle the net.Dial.
+	//
+	// Both http.Transport and http2.Transport allow the user to provide a custom
+	// dial function, and historically you only get the dial function from the
+	// Transport you're calling RoundTrip on.
+	ctx := context.WithValue(req.Context(), http2TransportContextKey{}, t)
+	req = req.WithContext(ctx)
+
+	return t.t1.RoundTrip(req)
+}
+
+func (t *Transport) closeIdleConnections() {
+	t.init()
+	t.t1.CloseIdleConnections()
+}
+
+func (t *Transport) newUserClientConn(c net.Conn) (*ClientConn, error) {
+	// http.Transport's NewClientConn doesn't provide a supported way to create
+	// a connection from a net.Conn. (This might be useful to add in the future?)
+	// We're going to craftily sneak one in via the context key, with the
+	// scheme of "http/2" telling NewClientConn to look for it.
+	ctx := context.WithValue(context.Background(), netConnContextKey{}, c)
+
+	nhcc, err := t.t1.NewClientConn(ctx, "http/2", "")
+	if err != nil {
+		return nil, err
+	}
+	cc := &ClientConn{cc: nhcc, tr: t, tconn: c}
+	nhcc.SetStateHook(cc.stateHook)
+	return cc, nil
+}
+
+// ClientConn is the state of a single HTTP/2 client connection to an
+// HTTP/2 server.
+type ClientConn struct {
+	cc         *http.ClientConn
+	tconn      net.Conn
+	tr         *Transport
+	doNotReuse bool
+
+	mu            sync.Mutex
+	closing       bool
+	closed        bool
+	roundTrips    int
+	reserved      int
+	starting      int
+	pending       int
+	maxConcurrent int
+	lastIdle      time.Time
+	shutdownc     chan struct{}
+
+	atomicReused uint32 // whether conn is being reused; atomic
+}
+
+func (cc *ClientConn) roundTrip(req *http.Request) (*http.Response, error) {
+	err := func() error {
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		if cc.doNotReuse {
+			return errClientConnUnusable
+		}
+		cc.roundTrips++
+		if cc.reserved > 0 {
+			// We've already reserved a concurrency slot for this request.
+			cc.reserved--
+		} else if cc.cc.Reserve() != nil {
+			// We don't seem to have an available concurrency slot,
+			// so bump the pending count (requests waiting for a slot).
+			cc.pending++
+		}
+		// ClientConn.Shutdown will not shut down the conn while
+		// cc.starting > 0 or cc.cc.InFlight() > 0.
+		//
+		// The starting state covers the gap between us deciding to
+		// start sending the request, and actually sending it.
+		cc.starting++
+		return nil
+	}()
+	if err != nil {
+		return nil, err
+	}
+	resp, err := cc.cc.RoundTrip(req)
+	cc.mu.Lock()
+	cc.starting--
+	if cc.pending > 0 {
+		// A request completing frees up a concurrency slot for
+		// a pending request to start.
+		cc.pending--
+	}
+	cc.updateStateLocked()
+	cc.mu.Unlock()
+	return resp, err
+}
+
+func (cc *ClientConn) canTakeNewRequest() bool {
+	return cc.cc.Available() > 0 && !cc.doNotReuse
+}
+
+func (cc *ClientConn) close() error {
+	return cc.cc.Close()
+}
+
+func (cc *ClientConn) ping(ctx context.Context) error {
+	// Ask net/http to ping its connection by sending a request with a method of ":ping".
+	_, err := cc.cc.RoundTrip((&http.Request{
+		Method: ":ping",
+	}).WithContext(ctx))
+	return err
+}
+
+func (cc *ClientConn) reserveNewRequest() bool {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	if cc.doNotReuse {
+		return false
+	}
+	if err := cc.cc.Reserve(); err != nil {
+		return false
+	}
+	cc.reserved++
+	return true
+}
+
+func (cc *ClientConn) setDoNotReuse() {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	cc.doNotReuse = true
+	cc.closing = true
+}
+
+func (cc *ClientConn) shutdown(ctx context.Context) error {
+	cc.mu.Lock()
+	inFlight := cc.cc.InFlight() + cc.starting
+	if inFlight > 0 && cc.shutdownc == nil {
+		cc.shutdownc = make(chan struct{})
+	}
+	shutdownc := cc.shutdownc
+	cc.mu.Unlock()
+	if shutdownc != nil {
+		// Wait for in-flight requests to finish.
+		select {
+		case <-shutdownc:
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+	cc.cc.Close()
+	return nil
+}
+
+func (cc *ClientConn) state() ClientConnState {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	cc.updateStateLocked()
+	return ClientConnState{
+		Closed:               cc.closed,
+		Closing:              cc.closing,
+		StreamsActive:        cc.cc.InFlight() - cc.reserved,
+		StreamsReserved:      cc.reserved,
+		StreamsPending:       cc.pending,
+		MaxConcurrentStreams: uint32(min(int64(cc.maxConcurrent), math.MaxUint32)),
+		LastIdle:             cc.lastIdle,
+	}
+}
+
+// stateHook is the http.ClientConn's state hook.
+func (cc *ClientConn) stateHook(*http.ClientConn) {
+	cc.mu.Lock()
+	defer cc.mu.Unlock()
+	cc.updateStateLocked()
+}
+
+func (cc *ClientConn) updateStateLocked() {
+	if cc.cc.Err() != nil && !cc.closed {
+		cc.closing = true
+		cc.closed = true
+		if cc.tr.ConnPool != nil {
+			// Do the ConnPool update in another goroutine,
+			// to avoid holding the conn mutex while it runs.
+			go cc.tr.ConnPool.MarkDead(cc)
+		}
+	}
+	if cc.cc.InFlight() == 0 && cc.roundTrips > 0 && cc.starting == 0 {
+		cc.lastIdle = time.Now()
+	}
+	if !cc.closed {
+		// This is slightly racy (a request could start or finish in between
+		// the Available and InFlight calls), but the best we can do given that
+		// the net/http ClientConn API doesn't expose the conn's max concurrency.
+		cc.maxConcurrent = cc.cc.Available() + cc.cc.InFlight()
+	}
+	if cc.shutdownc != nil && cc.cc.InFlight()+cc.starting == 0 {
+		close(cc.shutdownc)
+		cc.shutdownc = nil
+	}
+}
+
+func (cc *ClientConn) stopIdleTimer() {}
+
+// traceGotConn is (when http2legacy is not enabled) only used for tracing
+// connections acquired while using a user-provided ClientConnPool.
+func traceGotConn(req *http.Request, cc *ClientConn, reused bool) {
+	trace := httptrace.ContextClientTrace(req.Context())
+	if trace == nil || trace.GotConn == nil {
+		return
+	}
+	ci := httptrace.GotConnInfo{Conn: cc.tconn}
+	ci.Reused = reused
+	trace.GotConn(ci)
+}

vendor/golang.org/x/net/http2/writesched.go

@@ -2,51 +2,15 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import "fmt"
 
-// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
-// Methods are never called concurrently.
-type WriteScheduler interface {
-	// OpenStream opens a new stream in the write scheduler.
-	// It is illegal to call this with streamID=0 or with a streamID that is
-	// already open -- the call may panic.
-	OpenStream(streamID uint32, options OpenStreamOptions)
-
-	// CloseStream closes a stream in the write scheduler. Any frames queued on
-	// this stream should be discarded. It is illegal to call this on a stream
-	// that is not open -- the call may panic.
-	CloseStream(streamID uint32)
-
-	// AdjustStream adjusts the priority of the given stream. This may be called
-	// on a stream that has not yet been opened or has been closed. Note that
-	// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
-	// https://tools.ietf.org/html/rfc7540#section-5.1
-	AdjustStream(streamID uint32, priority PriorityParam)
-
-	// Push queues a frame in the scheduler. In most cases, this will not be
-	// called with wr.StreamID()!=0 unless that stream is currently open. The one
-	// exception is RST_STREAM frames, which may be sent on idle or closed streams.
-	Push(wr FrameWriteRequest)
-
-	// Pop dequeues the next frame to write. Returns false if no frames can
-	// be written. Frames with a given wr.StreamID() are Pop'd in the same
-	// order they are Push'd, except RST_STREAM frames. No frames should be
-	// discarded except by CloseStream.
-	Pop() (wr FrameWriteRequest, ok bool)
-}
-
-// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
-type OpenStreamOptions struct {
-	// PusherID is zero if the stream was initiated by the client. Otherwise,
-	// PusherID names the stream that pushed the newly opened stream.
-	PusherID uint32
-	// priority is used to set the priority of the newly opened stream.
-	priority PriorityParam
-}
-
 // FrameWriteRequest is a request to write a frame.
+//
+// Deprecated: User-provided write schedulers are deprecated.
 type FrameWriteRequest struct {
 	// write is the interface value that does the writing, once the
 	// WriteScheduler has selected this frame to write. The write

vendor/golang.org/x/net/http2/writesched_common.go

@@ -0,0 +1,90 @@
+// Copyright 2026 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
+
+// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
+// Methods are never called concurrently.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+type WriteScheduler interface {
+	// OpenStream opens a new stream in the write scheduler.
+	// It is illegal to call this with streamID=0 or with a streamID that is
+	// already open -- the call may panic.
+	OpenStream(streamID uint32, options OpenStreamOptions)
+
+	// CloseStream closes a stream in the write scheduler. Any frames queued on
+	// this stream should be discarded. It is illegal to call this on a stream
+	// that is not open -- the call may panic.
+	CloseStream(streamID uint32)
+
+	// AdjustStream adjusts the priority of the given stream. This may be called
+	// on a stream that has not yet been opened or has been closed. Note that
+	// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
+	// https://tools.ietf.org/html/rfc7540#section-5.1
+	AdjustStream(streamID uint32, priority PriorityParam)
+
+	// Push queues a frame in the scheduler. In most cases, this will not be
+	// called with wr.StreamID()!=0 unless that stream is currently open. The one
+	// exception is RST_STREAM frames, which may be sent on idle or closed streams.
+	Push(wr FrameWriteRequest)
+
+	// Pop dequeues the next frame to write. Returns false if no frames can
+	// be written. Frames with a given wr.StreamID() are Pop'd in the same
+	// order they are Push'd, except RST_STREAM frames. No frames should be
+	// discarded except by CloseStream.
+	Pop() (wr FrameWriteRequest, ok bool)
+}
+
+// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+type OpenStreamOptions struct {
+	// PusherID is zero if the stream was initiated by the client. Otherwise,
+	// PusherID names the stream that pushed the newly opened stream.
+	PusherID uint32
+	// priority is used to set the priority of the newly opened stream.
+	priority PriorityParam
+}
+
+// PriorityWriteSchedulerConfig configures a priorityWriteScheduler.
+//
+// Deprecated: User-provided write schedulers are deprecated.
+type PriorityWriteSchedulerConfig struct {
+	// MaxClosedNodesInTree controls the maximum number of closed streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   "It is possible for a stream to become closed while prioritization
+	//   information ... is in transit. ... This potentially creates suboptimal
+	//   prioritization, since the stream could be given a priority that is
+	//   different from what is intended. To avoid these problems, an endpoint
+	//   SHOULD retain stream prioritization state for a period after streams
+	//   become closed. The longer state is retained, the lower the chance that
+	//   streams are assigned incorrect or default priority values."
+	MaxClosedNodesInTree int
+
+	// MaxIdleNodesInTree controls the maximum number of idle streams to
+	// retain in the priority tree. Setting this to zero saves a small amount
+	// of memory at the cost of performance.
+	//
+	// See RFC 7540, Section 5.3.4:
+	//   Similarly, streams that are in the "idle" state can be assigned
+	//   priority or become a parent of other streams. This allows for the
+	//   creation of a grouping node in the dependency tree, which enables
+	//   more flexible expressions of priority. Idle streams begin with a
+	//   default priority (Section 5.3.5).
+	MaxIdleNodesInTree int
+
+	// ThrottleOutOfOrderWrites enables write throttling to help ensure that
+	// data is delivered in priority order. This works around a race where
+	// stream B depends on stream A and both streams are about to call Write
+	// to queue DATA frames. If B wins the race, a naive scheduler would eagerly
+	// write as much data from B as possible, but this is suboptimal because A
+	// is a higher-priority stream. With throttling enabled, we write a small
+	// amount of data from B to minimize the amount of bandwidth that B can
+	// steal from A.
+	ThrottleOutOfOrderWrites bool
+}

vendor/golang.org/x/net/http2/writesched_priority_rfc7540.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import (
@@ -13,49 +15,17 @@ import (
 // RFC 7540, Section 5.3.5: the default weight is 16.
 const priorityDefaultWeightRFC7540 = 15 // 16 = 15 + 1
 
-// PriorityWriteSchedulerConfig configures a priorityWriteScheduler.
-type PriorityWriteSchedulerConfig struct {
-	// MaxClosedNodesInTree controls the maximum number of closed streams to
-	// retain in the priority tree. Setting this to zero saves a small amount
-	// of memory at the cost of performance.
-	//
-	// See RFC 7540, Section 5.3.4:
-	//   "It is possible for a stream to become closed while prioritization
-	//   information ... is in transit. ... This potentially creates suboptimal
-	//   prioritization, since the stream could be given a priority that is
-	//   different from what is intended. To avoid these problems, an endpoint
-	//   SHOULD retain stream prioritization state for a period after streams
-	//   become closed. The longer state is retained, the lower the chance that
-	//   streams are assigned incorrect or default priority values."
-	MaxClosedNodesInTree int
-
-	// MaxIdleNodesInTree controls the maximum number of idle streams to
-	// retain in the priority tree. Setting this to zero saves a small amount
-	// of memory at the cost of performance.
-	//
-	// See RFC 7540, Section 5.3.4:
-	//   Similarly, streams that are in the "idle" state can be assigned
-	//   priority or become a parent of other streams. This allows for the
-	//   creation of a grouping node in the dependency tree, which enables
-	//   more flexible expressions of priority. Idle streams begin with a
-	//   default priority (Section 5.3.5).
-	MaxIdleNodesInTree int
-
-	// ThrottleOutOfOrderWrites enables write throttling to help ensure that
-	// data is delivered in priority order. This works around a race where
-	// stream B depends on stream A and both streams are about to call Write
-	// to queue DATA frames. If B wins the race, a naive scheduler would eagerly
-	// write as much data from B as possible, but this is suboptimal because A
-	// is a higher-priority stream. With throttling enabled, we write a small
-	// amount of data from B to minimize the amount of bandwidth that B can
-	// steal from A.
-	ThrottleOutOfOrderWrites bool
-}
-
 // NewPriorityWriteScheduler constructs a WriteScheduler that schedules
 // frames by following HTTP/2 priorities as described in RFC 7540 Section 5.3.
 // If cfg is nil, default options are used.
+//
+// Deprecated: The RFC 7540 write scheduler has known bugs and performance issues,
+// and RFC 7540 prioritization was deprecated in RFC 9113.
 func NewPriorityWriteScheduler(cfg *PriorityWriteSchedulerConfig) WriteScheduler {
+	return newPriorityWriteSchedulerRFC7540(cfg)
+}
+
+func newPriorityWriteSchedulerRFC7540(cfg *PriorityWriteSchedulerConfig) WriteScheduler {
 	if cfg == nil {
 		// For justification of these defaults, see:
 		// https://docs.google.com/document/d/1oLhNg1skaWD4_DtaoCxdSRN5erEXrH-KnLrMwEpOtFY

vendor/golang.org/x/net/http2/writesched_priority_rfc9218.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import (

vendor/golang.org/x/net/http2/writesched_random.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import "math"
@@ -10,6 +12,8 @@ import "math"
 // priorities. Control frames like SETTINGS and PING are written before DATA
 // frames, but if no control frames are queued and multiple streams have queued
 // HEADERS or DATA frames, Pop selects a ready stream arbitrarily.
+//
+// Deprecated: User-provided write schedulers are deprecated.
 func NewRandomWriteScheduler() WriteScheduler {
 	return &randomWriteScheduler{sq: make(map[uint32]*writeQueue)}
 }

vendor/golang.org/x/net/http2/writesched_roundrobin.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !(go1.27 && !http2legacy)
+
 package http2
 
 import (