Use mcdsl/terminal for all password prompts

Replace direct golang.org/x/term calls with mcdsl/terminal.ReadPassword
across mciasctl (6 sites), mciasgrpcctl (1 site), and mciasdb (1 site).
Aligns with the new CLI security standard in engineering-standards.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vendor/google.golang.org/grpc/internal/balancer/gracefulswitch/gracefulswitch.go

@@ -67,6 +67,10 @@ type Balancer struct {
 	// balancerCurrent before the UpdateSubConnState is called on the
 	// balancerCurrent.
 	currentMu sync.Mutex
+
+	// activeGoroutines tracks all the goroutines that this balancer has started
+	// and that should be waited on when the balancer closes.
+	activeGoroutines sync.WaitGroup
 }
 
 // swap swaps out the current lb with the pending lb and updates the ClientConn.
@@ -76,7 +80,9 @@ func (gsb *Balancer) swap() {
 	cur := gsb.balancerCurrent
 	gsb.balancerCurrent = gsb.balancerPending
 	gsb.balancerPending = nil
+	gsb.activeGoroutines.Add(1)
 	go func() {
+		defer gsb.activeGoroutines.Done()
 		gsb.currentMu.Lock()
 		defer gsb.currentMu.Unlock()
 		cur.Close()
@@ -274,6 +280,7 @@ func (gsb *Balancer) Close() {
 
 	currentBalancerToClose.Close()
 	pendingBalancerToClose.Close()
+	gsb.activeGoroutines.Wait()
 }
 
 // balancerWrapper wraps a balancer.Balancer, and overrides some Balancer
@@ -324,7 +331,12 @@ func (bw *balancerWrapper) UpdateState(state balancer.State) {
 	defer bw.gsb.mu.Unlock()
 	bw.lastState = state
 
+	// If Close() acquires the mutex before UpdateState(), the balancer
+	// will already have been removed from the current or pending state when
+	// reaching this point.
 	if !bw.gsb.balancerCurrentOrPending(bw) {
+		// Returning here ensures that (*Balancer).swap() is not invoked after
+		// (*Balancer).Close() and therefore prevents "use after close".
 		return
 	}
 

vendor/google.golang.org/grpc/internal/balancer/weight/weight.go

@@ -0,0 +1,66 @@
+/*
+ *
+ * Copyright 2025 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package weight contains utilities to manage endpoint weights. Weights are
+// used by LB policies such as ringhash to distribute load across multiple
+// endpoints.
+package weight
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/resolver"
+)
+
+// attributeKey is the type used as the key to store EndpointInfo in the
+// Attributes field of resolver.Endpoint.
+type attributeKey struct{}
+
+// EndpointInfo will be stored in the Attributes field of Endpoints in order to
+// use the ringhash balancer.
+type EndpointInfo struct {
+	Weight uint32
+}
+
+// Equal allows the values to be compared by Attributes.Equal.
+func (a EndpointInfo) Equal(o any) bool {
+	oa, ok := o.(EndpointInfo)
+	return ok && oa.Weight == a.Weight
+}
+
+// Set returns a copy of endpoint in which the Attributes field is updated with
+// EndpointInfo.
+func Set(endpoint resolver.Endpoint, epInfo EndpointInfo) resolver.Endpoint {
+	endpoint.Attributes = endpoint.Attributes.WithValue(attributeKey{}, epInfo)
+	return endpoint
+}
+
+// String returns a human-readable representation of EndpointInfo.
+// This method is intended for logging, testing, and debugging purposes only.
+// Do not rely on the output format, as it is not guaranteed to remain stable.
+func (a EndpointInfo) String() string {
+	return fmt.Sprintf("Weight: %d", a.Weight)
+}
+
+// FromEndpoint returns the EndpointInfo stored in the Attributes field of an
+// endpoint. It returns an empty EndpointInfo if attribute is not found.
+func FromEndpoint(endpoint resolver.Endpoint) EndpointInfo {
+	v := endpoint.Attributes.Value(attributeKey{})
+	ei, _ := v.(EndpointInfo)
+	return ei
+}

vendor/google.golang.org/grpc/internal/buffer/unbounded.go

@@ -83,6 +83,7 @@ func (b *Unbounded) Load() {
 		default:
 		}
 	} else if b.closing && !b.closed {
+		b.closed = true
 		close(b.c)
 	}
 }

vendor/google.golang.org/grpc/internal/channelz/trace.go

@@ -194,7 +194,7 @@ func (r RefChannelType) String() string {
 // If channelz is not turned ON, this will simply log the event descriptions.
 func AddTraceEvent(l grpclog.DepthLoggerV2, e Entity, depth int, desc *TraceEvent) {
 	// Log only the trace description associated with the bottom most entity.
-	d := fmt.Sprintf("[%s]%s", e, desc.Desc)
+	d := fmt.Sprintf("[%s] %s", e, desc.Desc)
 	switch desc.Severity {
 	case CtUnknown, CtInfo:
 		l.InfoDepth(depth+1, d)

vendor/google.golang.org/grpc/internal/envconfig/envconfig.go

@@ -26,31 +26,31 @@ import (
 )
 
 var (
-	// TXTErrIgnore is set if TXT errors should be ignored ("GRPC_GO_IGNORE_TXT_ERRORS" is not "false").
+	// EnableTXTServiceConfig is set if the DNS resolver should perform TXT
+	// lookups for service config ("GRPC_ENABLE_TXT_SERVICE_CONFIG" is not
+	// "false").
+	EnableTXTServiceConfig = boolFromEnv("GRPC_ENABLE_TXT_SERVICE_CONFIG", true)
+
+	// TXTErrIgnore is set if TXT errors should be ignored
+	// ("GRPC_GO_IGNORE_TXT_ERRORS" is not "false").
 	TXTErrIgnore = boolFromEnv("GRPC_GO_IGNORE_TXT_ERRORS", true)
+
 	// RingHashCap indicates the maximum ring size which defaults to 4096
 	// entries but may be overridden by setting the environment variable
 	// "GRPC_RING_HASH_CAP".  This does not override the default bounds
 	// checking which NACKs configs specifying ring sizes > 8*1024*1024 (~8M).
 	RingHashCap = uint64FromEnv("GRPC_RING_HASH_CAP", 4096, 1, 8*1024*1024)
+
 	// ALTSMaxConcurrentHandshakes is the maximum number of concurrent ALTS
 	// handshakes that can be performed.
 	ALTSMaxConcurrentHandshakes = uint64FromEnv("GRPC_ALTS_MAX_CONCURRENT_HANDSHAKES", 100, 1, 100)
+
 	// EnforceALPNEnabled is set if TLS connections to servers with ALPN disabled
 	// should be rejected. The HTTP/2 protocol requires ALPN to be enabled, this
 	// option is present for backward compatibility. This option may be overridden
 	// by setting the environment variable "GRPC_ENFORCE_ALPN_ENABLED" to "true"
 	// or "false".
 	EnforceALPNEnabled = boolFromEnv("GRPC_ENFORCE_ALPN_ENABLED", true)
-	// XDSFallbackSupport is the env variable that controls whether support for
-	// xDS fallback is turned on. If this is unset or is false, only the first
-	// xDS server in the list of server configs will be used.
-	XDSFallbackSupport = boolFromEnv("GRPC_EXPERIMENTAL_XDS_FALLBACK", true)
-	// NewPickFirstEnabled is set if the new pickfirst leaf policy is to be used
-	// instead of the exiting pickfirst implementation. This can be disabled by
-	// setting the environment variable "GRPC_EXPERIMENTAL_ENABLE_NEW_PICK_FIRST"
-	// to "false".
-	NewPickFirstEnabled = boolFromEnv("GRPC_EXPERIMENTAL_ENABLE_NEW_PICK_FIRST", true)
 
 	// XDSEndpointHashKeyBackwardCompat controls the parsing of the endpoint hash
 	// key from EDS LbEndpoint metadata. Endpoint hash keys can be disabled by
@@ -69,6 +69,41 @@ var (
 	// ALTSHandshakerKeepaliveParams is set if we should add the
 	// KeepaliveParams when dial the ALTS handshaker service.
 	ALTSHandshakerKeepaliveParams = boolFromEnv("GRPC_EXPERIMENTAL_ALTS_HANDSHAKER_KEEPALIVE_PARAMS", false)
+
+	// EnableDefaultPortForProxyTarget controls whether the resolver adds a default port 443
+	// to a target address that lacks one. This flag only has an effect when all of
+	// the following conditions are met:
+	//   - A connect proxy is being used.
+	//   - Target resolution is disabled.
+	//   - The DNS resolver is being used.
+	EnableDefaultPortForProxyTarget = boolFromEnv("GRPC_EXPERIMENTAL_ENABLE_DEFAULT_PORT_FOR_PROXY_TARGET", true)
+
+	// XDSAuthorityRewrite indicates whether xDS authority rewriting is enabled.
+	// This feature is defined in gRFC A81 and is enabled by setting the
+	// environment variable GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE to "true".
+	XDSAuthorityRewrite = boolFromEnv("GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE", false)
+
+	// PickFirstWeightedShuffling indicates whether weighted endpoint shuffling
+	// is enabled in the pick_first LB policy, as defined in gRFC A113. This
+	// feature can be disabled by setting the environment variable
+	// GRPC_EXPERIMENTAL_PF_WEIGHTED_SHUFFLING to "false".
+	PickFirstWeightedShuffling = boolFromEnv("GRPC_EXPERIMENTAL_PF_WEIGHTED_SHUFFLING", true)
+
+	// DisableStrictPathChecking indicates whether strict path checking is
+	// disabled. This feature can be disabled by setting the environment
+	// variable GRPC_GO_EXPERIMENTAL_DISABLE_STRICT_PATH_CHECKING to "true".
+	//
+	// When strict path checking is enabled, gRPC will reject requests with
+	// paths that do not conform to the gRPC over HTTP/2 specification found at
+	// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md.
+	//
+	// When disabled, gRPC will allow paths that do not contain a leading slash.
+	// Enabling strict path checking is recommended for security reasons, as it
+	// prevents potential path traversal vulnerabilities.
+	//
+	// A future release will remove this environment variable, enabling strict
+	// path checking behavior unconditionally.
+	DisableStrictPathChecking = boolFromEnv("GRPC_GO_EXPERIMENTAL_DISABLE_STRICT_PATH_CHECKING", false)
 )
 
 func boolFromEnv(envVar string, def bool) bool {

vendor/google.golang.org/grpc/internal/envconfig/xds.go

@@ -68,4 +68,15 @@ var (
 	// trust.  For more details, see:
 	// https://github.com/grpc/proposal/blob/master/A87-mtls-spiffe-support.md
 	XDSSPIFFEEnabled = boolFromEnv("GRPC_EXPERIMENTAL_XDS_MTLS_SPIFFE", false)
+
+	// XDSHTTPConnectEnabled is true if gRPC should parse custom Metadata
+	// configuring use of an HTTP CONNECT proxy via xDS from cluster resources.
+	// For more details, see:
+	// https://github.com/grpc/proposal/blob/master/A86-xds-http-connect.md
+	XDSHTTPConnectEnabled = boolFromEnv("GRPC_EXPERIMENTAL_XDS_HTTP_CONNECT", false)
+
+	// XDSBootstrapCallCredsEnabled controls if call credentials can be used in
+	// xDS bootstrap configuration via the `call_creds` field. For more details,
+	// see: https://github.com/grpc/proposal/blob/master/A97-xds-jwt-call-creds.md
+	XDSBootstrapCallCredsEnabled = boolFromEnv("GRPC_EXPERIMENTAL_XDS_BOOTSTRAP_CALL_CREDS", false)
 )

vendor/google.golang.org/grpc/internal/experimental.go

@@ -25,4 +25,11 @@ var (
 	// BufferPool is implemented by the grpc package and returns a server
 	// option to configure a shared buffer pool for a grpc.Server.
 	BufferPool any // func (grpc.SharedBufferPool) grpc.ServerOption
+
+	// SetDefaultBufferPool updates the default buffer pool.
+	SetDefaultBufferPool any // func(mem.BufferPool)
+
+	// AcceptCompressors is implemented by the grpc package and returns
+	// a call option that restricts the grpc-accept-encoding header for a call.
+	AcceptCompressors any // func(...string) grpc.CallOption
 )

vendor/google.golang.org/grpc/internal/grpcsync/callback_serializer.go

@@ -80,25 +80,11 @@ func (cs *CallbackSerializer) ScheduleOr(f func(ctx context.Context), onFailure
 func (cs *CallbackSerializer) run(ctx context.Context) {
 	defer close(cs.done)
 
-	// TODO: when Go 1.21 is the oldest supported version, this loop and Close
-	// can be replaced with:
-	//
-	// context.AfterFunc(ctx, cs.callbacks.Close)
-	for ctx.Err() == nil {
-		select {
-		case <-ctx.Done():
-			// Do nothing here. Next iteration of the for loop will not happen,
-			// since ctx.Err() would be non-nil.
-		case cb := <-cs.callbacks.Get():
-			cs.callbacks.Load()
-			cb.(func(context.Context))(ctx)
-		}
-	}
+	// Close the buffer when the context is canceled
+	// to prevent new callbacks from being added.
+	context.AfterFunc(ctx, cs.callbacks.Close)
 
-	// Close the buffer to prevent new callbacks from being added.
-	cs.callbacks.Close()
-
-	// Run all pending callbacks.
+	// Run all callbacks.
 	for cb := range cs.callbacks.Get() {
 		cs.callbacks.Load()
 		cb.(func(context.Context))(ctx)

vendor/google.golang.org/grpc/internal/idle/idle.go

@@ -21,7 +21,6 @@
 package idle
 
 import (
-	"fmt"
 	"math"
 	"sync"
 	"sync/atomic"
@@ -33,15 +32,15 @@ var timeAfterFunc = func(d time.Duration, f func()) *time.Timer {
 	return time.AfterFunc(d, f)
 }
 
-// Enforcer is the functionality provided by grpc.ClientConn to enter
-// and exit from idle mode.
-type Enforcer interface {
-	ExitIdleMode() error
+// ClientConn is the functionality provided by grpc.ClientConn to enter and exit
+// from idle mode.
+type ClientConn interface {
+	ExitIdleMode()
 	EnterIdleMode()
 }
 
-// Manager implements idleness detection and calls the configured Enforcer to
-// enter/exit idle mode when appropriate.  Must be created by NewManager.
+// Manager implements idleness detection and calls the ClientConn to enter/exit
+// idle mode when appropriate. Must be created by NewManager.
 type Manager struct {
 	// State accessed atomically.
 	lastCallEndTime           int64 // Unix timestamp in nanos; time when the most recent RPC completed.
@@ -51,8 +50,8 @@ type Manager struct {
 
 	// Can be accessed without atomics or mutex since these are set at creation
 	// time and read-only after that.
-	enforcer Enforcer // Functionality provided by grpc.ClientConn.
-	timeout  time.Duration
+	cc      ClientConn // Functionality provided by grpc.ClientConn.
+	timeout time.Duration
 
 	// idleMu is used to guarantee mutual exclusion in two scenarios:
 	// - Opposing intentions:
@@ -72,9 +71,9 @@ type Manager struct {
 
 // NewManager creates a new idleness manager implementation for the
 // given idle timeout.  It begins in idle mode.
-func NewManager(enforcer Enforcer, timeout time.Duration) *Manager {
+func NewManager(cc ClientConn, timeout time.Duration) *Manager {
 	return &Manager{
-		enforcer:         enforcer,
+		cc:               cc,
 		timeout:          timeout,
 		actuallyIdle:     true,
 		activeCallsCount: -math.MaxInt32,
@@ -127,7 +126,7 @@ func (m *Manager) handleIdleTimeout() {
 
 	// Now that we've checked that there has been no activity, attempt to enter
 	// idle mode, which is very likely to succeed.
-	if m.tryEnterIdleMode() {
+	if m.tryEnterIdleMode(true) {
 		// Successfully entered idle mode. No timer needed until we exit idle.
 		return
 	}
@@ -142,10 +141,13 @@ func (m *Manager) handleIdleTimeout() {
 // that, it performs a last minute check to ensure that no new RPC has come in,
 // making the channel active.
 //
+// checkActivity controls if a check for RPC activity, since the last time the
+// idle_timeout fired, is made.
+
 // Return value indicates whether or not the channel moved to idle mode.
 //
 // Holds idleMu which ensures mutual exclusion with exitIdleMode.
-func (m *Manager) tryEnterIdleMode() bool {
+func (m *Manager) tryEnterIdleMode(checkActivity bool) bool {
 	// Setting the activeCallsCount to -math.MaxInt32 indicates to OnCallBegin()
 	// that the channel is either in idle mode or is trying to get there.
 	if !atomic.CompareAndSwapInt32(&m.activeCallsCount, 0, -math.MaxInt32) {
@@ -166,7 +168,7 @@ func (m *Manager) tryEnterIdleMode() bool {
 		atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
 		return false
 	}
-	if atomic.LoadInt32(&m.activeSinceLastTimerCheck) == 1 {
+	if checkActivity && atomic.LoadInt32(&m.activeSinceLastTimerCheck) == 1 {
 		// A very short RPC could have come in (and also finished) after we
 		// checked for calls count and activity in handleIdleTimeout(), but
 		// before the CAS operation. So, we need to check for activity again.
@@ -177,44 +179,37 @@ func (m *Manager) tryEnterIdleMode() bool {
 	// No new RPCs have come in since we set the active calls count value to
 	// -math.MaxInt32. And since we have the lock, it is safe to enter idle mode
 	// unconditionally now.
-	m.enforcer.EnterIdleMode()
+	m.cc.EnterIdleMode()
 	m.actuallyIdle = true
 	return true
 }
 
 // EnterIdleModeForTesting instructs the channel to enter idle mode.
 func (m *Manager) EnterIdleModeForTesting() {
-	m.tryEnterIdleMode()
+	m.tryEnterIdleMode(false)
 }
 
 // OnCallBegin is invoked at the start of every RPC.
-func (m *Manager) OnCallBegin() error {
+func (m *Manager) OnCallBegin() {
 	if m.isClosed() {
-		return nil
+		return
 	}
 
 	if atomic.AddInt32(&m.activeCallsCount, 1) > 0 {
 		// Channel is not idle now. Set the activity bit and allow the call.
 		atomic.StoreInt32(&m.activeSinceLastTimerCheck, 1)
-		return nil
+		return
 	}
 
 	// Channel is either in idle mode or is in the process of moving to idle
 	// mode. Attempt to exit idle mode to allow this RPC.
-	if err := m.ExitIdleMode(); err != nil {
-		// Undo the increment to calls count, and return an error causing the
-		// RPC to fail.
-		atomic.AddInt32(&m.activeCallsCount, -1)
-		return err
-	}
-
+	m.ExitIdleMode()
 	atomic.StoreInt32(&m.activeSinceLastTimerCheck, 1)
-	return nil
 }
 
-// ExitIdleMode instructs m to call the enforcer's ExitIdleMode and update m's
+// ExitIdleMode instructs m to call the ClientConn's ExitIdleMode and update its
 // internal state.
-func (m *Manager) ExitIdleMode() error {
+func (m *Manager) ExitIdleMode() {
 	// Holds idleMu which ensures mutual exclusion with tryEnterIdleMode.
 	m.idleMu.Lock()
 	defer m.idleMu.Unlock()
@@ -231,12 +226,10 @@ func (m *Manager) ExitIdleMode() error {
 		//   m.ExitIdleMode.
 		//
 		// In any case, there is nothing to do here.
-		return nil
+		return
 	}
 
-	if err := m.enforcer.ExitIdleMode(); err != nil {
-		return fmt.Errorf("failed to exit idle mode: %w", err)
-	}
+	m.cc.ExitIdleMode()
 
 	// Undo the idle entry process. This also respects any new RPC attempts.
 	atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
@@ -244,7 +237,23 @@ func (m *Manager) ExitIdleMode() error {
 
 	// Start a new timer to fire after the configured idle timeout.
 	m.resetIdleTimerLocked(m.timeout)
-	return nil
+}
+
+// UnsafeSetNotIdle instructs the Manager to update its internal state to
+// reflect the reality that the channel is no longer in IDLE mode.
+//
+// N.B. This method is intended only for internal use by the gRPC client
+// when it exits IDLE mode **manually** from `Dial`. The callsite must ensure:
+//   - The channel was **actually in IDLE mode** immediately prior to the call.
+//   - There is **no concurrent activity** that could cause the channel to exit
+//     IDLE mode *naturally* at the same time.
+func (m *Manager) UnsafeSetNotIdle() {
+	m.idleMu.Lock()
+	defer m.idleMu.Unlock()
+
+	atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
+	m.actuallyIdle = false
+	m.resetIdleTimerLocked(m.timeout)
 }
 
 // OnCallEnd is invoked at the end of every RPC.

vendor/google.golang.org/grpc/internal/internal.go

@@ -182,35 +182,6 @@ var (
 	// other features, including the CSDS service.
 	NewXDSResolverWithClientForTesting any // func(xdsclient.XDSClient) (resolver.Builder, error)
 
-	// RegisterRLSClusterSpecifierPluginForTesting registers the RLS Cluster
-	// Specifier Plugin for testing purposes, regardless of the XDSRLS environment
-	// variable.
-	//
-	// TODO: Remove this function once the RLS env var is removed.
-	RegisterRLSClusterSpecifierPluginForTesting func()
-
-	// UnregisterRLSClusterSpecifierPluginForTesting unregisters the RLS Cluster
-	// Specifier Plugin for testing purposes. This is needed because there is no way
-	// to unregister the RLS Cluster Specifier Plugin after registering it solely
-	// for testing purposes using RegisterRLSClusterSpecifierPluginForTesting().
-	//
-	// TODO: Remove this function once the RLS env var is removed.
-	UnregisterRLSClusterSpecifierPluginForTesting func()
-
-	// RegisterRBACHTTPFilterForTesting registers the RBAC HTTP Filter for testing
-	// purposes, regardless of the RBAC environment variable.
-	//
-	// TODO: Remove this function once the RBAC env var is removed.
-	RegisterRBACHTTPFilterForTesting func()
-
-	// UnregisterRBACHTTPFilterForTesting unregisters the RBAC HTTP Filter for
-	// testing purposes. This is needed because there is no way to unregister the
-	// HTTP Filter after registering it solely for testing purposes using
-	// RegisterRBACHTTPFilterForTesting().
-	//
-	// TODO: Remove this function once the RBAC env var is removed.
-	UnregisterRBACHTTPFilterForTesting func()
-
 	// ORCAAllowAnyMinReportingInterval is for examples/orca use ONLY.
 	ORCAAllowAnyMinReportingInterval any // func(so *orca.ServiceOptions)
 
@@ -240,22 +211,11 @@ var (
 	// default resolver scheme.
 	UserSetDefaultScheme = false
 
-	// ConnectedAddress returns the connected address for a SubConnState. The
-	// address is only valid if the state is READY.
-	ConnectedAddress any // func (scs SubConnState) resolver.Address
-
-	// SetConnectedAddress sets the connected address for a SubConnState.
-	SetConnectedAddress any // func(scs *SubConnState, addr resolver.Address)
-
 	// SnapshotMetricRegistryForTesting snapshots the global data of the metric
 	// registry. Returns a cleanup function that sets the metric registry to its
 	// original state. Only called in testing functions.
 	SnapshotMetricRegistryForTesting func() func()
 
-	// SetDefaultBufferPoolForTesting updates the default buffer pool, for
-	// testing purposes.
-	SetDefaultBufferPoolForTesting any // func(mem.BufferPool)
-
 	// SetBufferPoolingThresholdForTesting updates the buffer pooling threshold, for
 	// testing purposes.
 	SetBufferPoolingThresholdForTesting any // func(int)
@@ -273,6 +233,18 @@ var (
 	// When set, the function will be called before the stream enters
 	// the blocking state.
 	NewStreamWaitingForResolver = func() {}
+
+	// AddressToTelemetryLabels is an xDS-provided function to extract telemetry
+	// labels from a resolver.Address. Callers must assert its type before calling.
+	AddressToTelemetryLabels any // func(addr resolver.Address) map[string]string
+
+	// AsyncReporterCleanupDelegate is initialized to a pass-through function by
+	// default (production behavior), allowing tests to swap it with an
+	// implementation which tracks registration of async reporter and its
+	// corresponding cleanup.
+	AsyncReporterCleanupDelegate = func(cleanup func()) func() {
+		return cleanup
+	}
 )
 
 // HealthChecker defines the signature of the client-side LB channel health
@@ -320,3 +292,9 @@ type EnforceClientConnEmbedding interface {
 type Timer interface {
 	Stop() bool
 }
+
+// EnforceMetricsRecorderEmbedding is used to enforce proper MetricsRecorder
+// implementation embedding.
+type EnforceMetricsRecorderEmbedding interface {
+	enforceMetricsRecorderEmbedding()
+}

vendor/google.golang.org/grpc/internal/resolver/delegatingresolver/delegatingresolver.go

@@ -22,11 +22,13 @@ package delegatingresolver
 
 import (
 	"fmt"
+	"net"
 	"net/http"
 	"net/url"
 	"sync"
 
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/envconfig"
 	"google.golang.org/grpc/internal/proxyattributes"
 	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/internal/transport/networktype"
@@ -40,6 +42,8 @@ var (
 	HTTPSProxyFromEnvironment = http.ProxyFromEnvironment
 )
 
+const defaultPort = "443"
+
 // delegatingResolver manages both target URI and proxy address resolution by
 // delegating these tasks to separate child resolvers. Essentially, it acts as
 // an intermediary between the gRPC ClientConn and the child resolvers.
@@ -107,10 +111,18 @@ func New(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOpti
 		targetResolver: nopResolver{},
 	}
 
+	addr := target.Endpoint()
 	var err error
-	r.proxyURL, err = proxyURLForTarget(target.Endpoint())
+	if target.URL.Scheme == "dns" && !targetResolutionEnabled && envconfig.EnableDefaultPortForProxyTarget {
+		addr, err = parseTarget(addr)
+		if err != nil {
+			return nil, fmt.Errorf("delegating_resolver: invalid target address %q: %v", target.Endpoint(), err)
+		}
+	}
+
+	r.proxyURL, err = proxyURLForTarget(addr)
 	if err != nil {
-		return nil, fmt.Errorf("delegating_resolver: failed to determine proxy URL for target %s: %v", target, err)
+		return nil, fmt.Errorf("delegating_resolver: failed to determine proxy URL for target %q: %v", target, err)
 	}
 
 	// proxy is not configured or proxy address excluded using `NO_PROXY` env
@@ -132,8 +144,8 @@ func New(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOpti
 	// bypass the target resolver and store the unresolved target address.
 	if target.URL.Scheme == "dns" && !targetResolutionEnabled {
 		r.targetResolverState = &resolver.State{
-			Addresses: []resolver.Address{{Addr: target.Endpoint()}},
-			Endpoints: []resolver.Endpoint{{Addresses: []resolver.Address{{Addr: target.Endpoint()}}}},
+			Addresses: []resolver.Address{{Addr: addr}},
+			Endpoints: []resolver.Endpoint{{Addresses: []resolver.Address{{Addr: addr}}}},
 		}
 		r.updateTargetResolverState(*r.targetResolverState)
 		return r, nil
@@ -202,6 +214,44 @@ func needsProxyResolver(state *resolver.State) bool {
 	return false
 }
 
+// parseTarget takes a target string and ensures it is a valid "host:port" target.
+//
+// It does the following:
+//  1. If the target already has a port (e.g., "host:port", "[ipv6]:port"),
+//     it is returned as is.
+//  2. If the host part is empty (e.g., ":80"), it defaults to "localhost",
+//     returning "localhost:80".
+//  3. If the target is missing a port (e.g., "host", "ipv6"), the defaultPort
+//     is added.
+//
+// An error is returned for empty targets or targets with a trailing colon
+// but no port (e.g., "host:").
+func parseTarget(target string) (string, error) {
+	if target == "" {
+		return "", fmt.Errorf("missing address")
+	}
+
+	host, port, err := net.SplitHostPort(target)
+	if err != nil {
+		// If SplitHostPort fails, it's likely because the port is missing.
+		// We append the default port and return the result.
+		return net.JoinHostPort(target, defaultPort), nil
+	}
+
+	// If SplitHostPort succeeds, we check for edge cases.
+	if port == "" {
+		// A success with an empty port means the target had a trailing colon,
+		// e.g., "host:", which is an error.
+		return "", fmt.Errorf("missing port after port-separator colon")
+	}
+	if host == "" {
+		// A success with an empty host means the target was like ":80".
+		// We default the host to "localhost".
+		host = "localhost"
+	}
+	return net.JoinHostPort(host, port), nil
+}
+
 func skipProxy(address resolver.Address) bool {
 	// Avoid proxy when network is not tcp.
 	networkType, ok := networktype.Get(address)

vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go

@@ -125,20 +125,23 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
 	// IP address.
 	if ipAddr, err := formatIP(host); err == nil {
 		addr := []resolver.Address{{Addr: ipAddr + ":" + port}}
-		cc.UpdateState(resolver.State{Addresses: addr})
+		cc.UpdateState(resolver.State{
+			Addresses: addr,
+			Endpoints: []resolver.Endpoint{{Addresses: addr}},
+		})
 		return deadResolver{}, nil
 	}
 
 	// DNS address (non-IP).
 	ctx, cancel := context.WithCancel(context.Background())
 	d := &dnsResolver{
-		host:                 host,
-		port:                 port,
-		ctx:                  ctx,
-		cancel:               cancel,
-		cc:                   cc,
-		rn:                   make(chan struct{}, 1),
-		disableServiceConfig: opts.DisableServiceConfig,
+		host:                host,
+		port:                port,
+		ctx:                 ctx,
+		cancel:              cancel,
+		cc:                  cc,
+		rn:                  make(chan struct{}, 1),
+		enableServiceConfig: envconfig.EnableTXTServiceConfig && !opts.DisableServiceConfig,
 	}
 
 	d.resolver, err = internal.NewNetResolver(target.URL.Host)
@@ -181,8 +184,8 @@ type dnsResolver struct {
 	// finishes, race detector sometimes will warn lookup (READ the lookup
 	// function pointers) inside watcher() goroutine has data race with
 	// replaceNetFunc (WRITE the lookup function pointers).
-	wg                   sync.WaitGroup
-	disableServiceConfig bool
+	wg                  sync.WaitGroup
+	enableServiceConfig bool
 }
 
 // ResolveNow invoke an immediate resolution of the target that this
@@ -342,11 +345,19 @@ func (d *dnsResolver) lookup() (*resolver.State, error) {
 		return nil, hostErr
 	}
 
-	state := resolver.State{Addresses: addrs}
+	eps := make([]resolver.Endpoint, 0, len(addrs))
+	for _, addr := range addrs {
+		eps = append(eps, resolver.Endpoint{Addresses: []resolver.Address{addr}})
+	}
+
+	state := resolver.State{
+		Addresses: addrs,
+		Endpoints: eps,
+	}
 	if len(srv) > 0 {
 		state = grpclbstate.Set(state, &grpclbstate.State{BalancerAddresses: srv})
 	}
-	if !d.disableServiceConfig {
+	if d.enableServiceConfig {
 		state.ServiceConfig = d.lookupTXT(ctx)
 	}
 	return &state, nil

vendor/google.golang.org/grpc/internal/stats/metrics_recorder_list.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 
 	estats "google.golang.org/grpc/experimental/stats"
+	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/stats"
 )
 
@@ -28,6 +29,7 @@ import (
 // It eats any record calls where the label values provided do not match the
 // number of label keys.
 type MetricsRecorderList struct {
+	internal.EnforceMetricsRecorderEmbedding
 	// metricsRecorders are the metrics recorders this list will forward to.
 	metricsRecorders []estats.MetricsRecorder
 }
@@ -64,6 +66,16 @@ func (l *MetricsRecorderList) RecordInt64Count(handle *estats.Int64CountHandle,
 	}
 }
 
+// RecordInt64UpDownCount records the measurement alongside labels on the int
+// count associated with the provided handle.
+func (l *MetricsRecorderList) RecordInt64UpDownCount(handle *estats.Int64UpDownCountHandle, incr int64, labels ...string) {
+	verifyLabels(handle.Descriptor(), labels...)
+
+	for _, metricRecorder := range l.metricsRecorders {
+		metricRecorder.RecordInt64UpDownCount(handle, incr, labels...)
+	}
+}
+
 // RecordFloat64Count records the measurement alongside labels on the float
 // count associated with the provided handle.
 func (l *MetricsRecorderList) RecordFloat64Count(handle *estats.Float64CountHandle, incr float64, labels ...string) {
@@ -103,3 +115,61 @@ func (l *MetricsRecorderList) RecordInt64Gauge(handle *estats.Int64GaugeHandle,
 		metricRecorder.RecordInt64Gauge(handle, incr, labels...)
 	}
 }
+
+// RegisterAsyncReporter forwards the registration to all underlying metrics
+// recorders.
+//
+// It returns a cleanup function that, when called, invokes the cleanup function
+// returned by each underlying recorder, ensuring the reporter is unregistered
+// from all of them.
+func (l *MetricsRecorderList) RegisterAsyncReporter(reporter estats.AsyncMetricReporter, metrics ...estats.AsyncMetric) func() {
+	descriptorsMap := make(map[*estats.MetricDescriptor]bool, len(metrics))
+	for _, m := range metrics {
+		descriptorsMap[m.Descriptor()] = true
+	}
+	unregisterFns := make([]func(), 0, len(l.metricsRecorders))
+	for _, mr := range l.metricsRecorders {
+		// Wrap the AsyncMetricsRecorder to intercept calls to RecordInt64Gauge
+		// and validate the labels.
+		wrappedCallback := func(recorder estats.AsyncMetricsRecorder) error {
+			wrappedRecorder := &asyncRecorderWrapper{
+				delegate:    recorder,
+				descriptors: descriptorsMap,
+			}
+			return reporter.Report(wrappedRecorder)
+		}
+		unregisterFns = append(unregisterFns, mr.RegisterAsyncReporter(estats.AsyncMetricReporterFunc(wrappedCallback), metrics...))
+	}
+
+	// Wrap the cleanup function using the internal delegate.
+	// In production, this returns realCleanup as-is.
+	// In tests, the leak checker can swap this to track the registration lifetime.
+	return internal.AsyncReporterCleanupDelegate(defaultCleanUp(unregisterFns))
+}
+
+func defaultCleanUp(unregisterFns []func()) func() {
+	return func() {
+		for _, unregister := range unregisterFns {
+			unregister()
+		}
+	}
+}
+
+type asyncRecorderWrapper struct {
+	delegate    estats.AsyncMetricsRecorder
+	descriptors map[*estats.MetricDescriptor]bool
+}
+
+// RecordIntAsync64Gauge records the measurement alongside labels on the int
+// gauge associated with the provided handle.
+func (w *asyncRecorderWrapper) RecordInt64AsyncGauge(handle *estats.Int64AsyncGaugeHandle, value int64, labels ...string) {
+	// Ensure only metrics for descriptors passed during callback registration
+	// are emitted.
+	d := handle.Descriptor()
+	if _, ok := w.descriptors[d]; !ok {
+		return
+	}
+	// Validate labels and delegate.
+	verifyLabels(d, labels...)
+	w.delegate.RecordInt64AsyncGauge(handle, value, labels...)
+}

vendor/google.golang.org/grpc/internal/stats/stats.go

@@ -0,0 +1,70 @@
+/*
+ *
+ * Copyright 2025 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package stats
+
+import (
+	"context"
+
+	"google.golang.org/grpc/stats"
+)
+
+type combinedHandler struct {
+	handlers []stats.Handler
+}
+
+// NewCombinedHandler combines multiple stats.Handlers into a single handler.
+//
+// It returns nil if no handlers are provided. If only one handler is
+// provided, it is returned directly without wrapping.
+func NewCombinedHandler(handlers ...stats.Handler) stats.Handler {
+	switch len(handlers) {
+	case 0:
+		return nil
+	case 1:
+		return handlers[0]
+	default:
+		return &combinedHandler{handlers: handlers}
+	}
+}
+
+func (ch *combinedHandler) TagRPC(ctx context.Context, info *stats.RPCTagInfo) context.Context {
+	for _, h := range ch.handlers {
+		ctx = h.TagRPC(ctx, info)
+	}
+	return ctx
+}
+
+func (ch *combinedHandler) HandleRPC(ctx context.Context, stats stats.RPCStats) {
+	for _, h := range ch.handlers {
+		h.HandleRPC(ctx, stats)
+	}
+}
+
+func (ch *combinedHandler) TagConn(ctx context.Context, info *stats.ConnTagInfo) context.Context {
+	for _, h := range ch.handlers {
+		ctx = h.TagConn(ctx, info)
+	}
+	return ctx
+}
+
+func (ch *combinedHandler) HandleConn(ctx context.Context, stats stats.ConnStats) {
+	for _, h := range ch.handlers {
+		h.HandleConn(ctx, stats)
+	}
+}

vendor/google.golang.org/grpc/internal/transport/client_stream.go

@@ -24,30 +24,34 @@ import (
 	"golang.org/x/net/http2"
 	"google.golang.org/grpc/mem"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 )
 
 // ClientStream implements streaming functionality for a gRPC client.
 type ClientStream struct {
-	*Stream // Embed for common stream functionality.
+	Stream // Embed for common stream functionality.
 
 	ct       *http2Client
 	done     chan struct{} // closed at the end of stream to unblock writers.
 	doneFunc func()        // invoked at the end of stream.
 
-	headerChan       chan struct{} // closed to indicate the end of header metadata.
-	headerChanClosed uint32        // set when headerChan is closed. Used to avoid closing headerChan multiple times.
+	headerChan chan struct{} // closed to indicate the end of header metadata.
+	header     metadata.MD   // the received header metadata
+
+	status *status.Status // the status error received from the server
+
+	// Non-pointer fields are at the end to optimize GC allocations.
+
 	// headerValid indicates whether a valid header was received.  Only
 	// meaningful after headerChan is closed (always call waitOnHeader() before
 	// reading its value).
-	headerValid bool
-	header      metadata.MD // the received header metadata
-	noHeaders   bool        // set if the client never received headers (set only after the stream is done).
-
-	bytesReceived atomic.Bool // indicates whether any bytes have been received on this stream
-	unprocessed   atomic.Bool // set if the server sends a refused stream or GOAWAY including this stream
-
-	status *status.Status // the status error received from the server
+	headerValid      bool
+	noHeaders        bool          // set if the client never received headers (set only after the stream is done).
+	headerChanClosed uint32        // set when headerChan is closed. Used to avoid closing headerChan multiple times.
+	bytesReceived    atomic.Bool   // indicates whether any bytes have been received on this stream
+	unprocessed      atomic.Bool   // set if the server sends a refused stream or GOAWAY including this stream
+	statsHandler     stats.Handler // nil for internal streams (e.g., health check, ORCA) where telemetry is not supported.
 }
 
 // Read reads an n byte message from the input stream.
@@ -142,3 +146,11 @@ func (s *ClientStream) TrailersOnly() bool {
 func (s *ClientStream) Status() *status.Status {
 	return s.status
 }
+
+func (s *ClientStream) requestRead(n int) {
+	s.ct.adjustWindow(s, uint32(n))
+}
+
+func (s *ClientStream) updateWindow(n int) {
+	s.ct.updateWindow(s, uint32(n))
+}

vendor/google.golang.org/grpc/internal/transport/controlbuf.go

@@ -24,16 +24,13 @@ import (
 	"fmt"
 	"net"
 	"runtime"
-	"strconv"
 	"sync"
 	"sync/atomic"
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/internal/grpclog"
-	"google.golang.org/grpc/internal/grpcutil"
 	"google.golang.org/grpc/mem"
-	"google.golang.org/grpc/status"
 )
 
 var updateHeaderTblSize = func(e *hpack.Encoder, v uint32) {
@@ -147,11 +144,9 @@ type cleanupStream struct {
 func (c *cleanupStream) isTransportResponseFrame() bool { return c.rst } // Results in a RST_STREAM
 
 type earlyAbortStream struct {
-	httpStatus     uint32
-	streamID       uint32
-	contentSubtype string
-	status         *status.Status
-	rst            bool
+	streamID uint32
+	rst      bool
+	hf       []hpack.HeaderField // Pre-built header fields
 }
 
 func (*earlyAbortStream) isTransportResponseFrame() bool { return false }
@@ -496,6 +491,16 @@ const (
 	serverSide
 )
 
+// maxWriteBufSize is the maximum length (number of elements) the cached
+// writeBuf can grow to. The length depends on the number of buffers
+// contained within the BufferSlice produced by the codec, which is
+// generally small.
+//
+// If a writeBuf larger than this limit is required, it will be allocated
+// and freed after use, rather than being cached. This avoids holding
+// on to large amounts of memory.
+const maxWriteBufSize = 64
+
 // Loopy receives frames from the control buffer.
 // Each frame is handled individually; most of the work done by loopy goes
 // into handling data frames. Loopy maintains a queue of active streams, and each
@@ -530,6 +535,8 @@ type loopyWriter struct {
 
 	// Side-specific handlers
 	ssGoAwayHandler func(*goAway) (bool, error)
+
+	writeBuf [][]byte // cached slice to avoid heap allocations for calls to mem.Reader.Peek.
 }
 
 func newLoopyWriter(s side, fr *framer, cbuf *controlBuffer, bdpEst *bdpEstimator, conn net.Conn, logger *grpclog.PrefixLogger, goAwayHandler func(*goAway) (bool, error), bufferPool mem.BufferPool) *loopyWriter {
@@ -665,11 +672,10 @@ func (l *loopyWriter) incomingSettingsHandler(s *incomingSettings) error {
 
 func (l *loopyWriter) registerStreamHandler(h *registerStream) {
 	str := &outStream{
-		id:     h.streamID,
-		state:  empty,
-		itl:    &itemList{},
-		wq:     h.wq,
-		reader: mem.BufferSlice{}.Reader(),
+		id:    h.streamID,
+		state: empty,
+		itl:   &itemList{},
+		wq:    h.wq,
 	}
 	l.estdStreams[h.streamID] = str
 }
@@ -701,11 +707,10 @@ func (l *loopyWriter) headerHandler(h *headerFrame) error {
 	}
 	// Case 2: Client wants to originate stream.
 	str := &outStream{
-		id:     h.streamID,
-		state:  empty,
-		itl:    &itemList{},
-		wq:     h.wq,
-		reader: mem.BufferSlice{}.Reader(),
+		id:    h.streamID,
+		state: empty,
+		itl:   &itemList{},
+		wq:    h.wq,
 	}
 	return l.originateStream(str, h)
 }
@@ -833,18 +838,7 @@ func (l *loopyWriter) earlyAbortStreamHandler(eas *earlyAbortStream) error {
 	if l.side == clientSide {
 		return errors.New("earlyAbortStream not handled on client")
 	}
-	// In case the caller forgets to set the http status, default to 200.
-	if eas.httpStatus == 0 {
-		eas.httpStatus = 200
-	}
-	headerFields := []hpack.HeaderField{
-		{Name: ":status", Value: strconv.Itoa(int(eas.httpStatus))},
-		{Name: "content-type", Value: grpcutil.ContentType(eas.contentSubtype)},
-		{Name: "grpc-status", Value: strconv.Itoa(int(eas.status.Code()))},
-		{Name: "grpc-message", Value: encodeGrpcMessage(eas.status.Message())},
-	}
-
-	if err := l.writeHeader(eas.streamID, true, headerFields, nil); err != nil {
+	if err := l.writeHeader(eas.streamID, true, eas.hf, nil); err != nil {
 		return err
 	}
 	if eas.rst {
@@ -948,11 +942,11 @@ func (l *loopyWriter) processData() (bool, error) {
 	if str == nil {
 		return true, nil
 	}
-	reader := str.reader
+	reader := &str.reader
 	dataItem := str.itl.peek().(*dataFrame) // Peek at the first data item this stream.
 	if !dataItem.processing {
 		dataItem.processing = true
-		str.reader.Reset(dataItem.data)
+		reader.Reset(dataItem.data)
 		dataItem.data.Free()
 	}
 	// A data item is represented by a dataFrame, since it later translates into
@@ -964,11 +958,11 @@ func (l *loopyWriter) processData() (bool, error) {
 
 	if len(dataItem.h) == 0 && reader.Remaining() == 0 { // Empty data frame
 		// Client sends out empty data frame with endStream = true
-		if err := l.framer.fr.WriteData(dataItem.streamID, dataItem.endStream, nil); err != nil {
+		if err := l.framer.writeData(dataItem.streamID, dataItem.endStream, nil); err != nil {
 			return false, err
 		}
 		str.itl.dequeue() // remove the empty data item from stream
-		_ = reader.Close()
+		reader.Close()
 		if str.itl.isEmpty() {
 			str.state = empty
 		} else if trailer, ok := str.itl.peek().(*headerFrame); ok { // the next item is trailers.
@@ -1001,25 +995,20 @@ func (l *loopyWriter) processData() (bool, error) {
 	remainingBytes := len(dataItem.h) + reader.Remaining() - hSize - dSize
 	size := hSize + dSize
 
-	var buf *[]byte
-
-	if hSize != 0 && dSize == 0 {
-		buf = &dataItem.h
-	} else {
-		// Note: this is only necessary because the http2.Framer does not support
-		// partially writing a frame, so the sequence must be materialized into a buffer.
-		// TODO: Revisit once https://github.com/golang/go/issues/66655 is addressed.
-		pool := l.bufferPool
-		if pool == nil {
-			// Note that this is only supposed to be nil in tests. Otherwise, stream is
-			// always initialized with a BufferPool.
-			pool = mem.DefaultBufferPool()
+	l.writeBuf = l.writeBuf[:0]
+	if hSize > 0 {
+		l.writeBuf = append(l.writeBuf, dataItem.h[:hSize])
+	}
+	if dSize > 0 {
+		var err error
+		l.writeBuf, err = reader.Peek(dSize, l.writeBuf)
+		if err != nil {
+			// This must never happen since the reader must have at least dSize
+			// bytes.
+			// Log an error to fail tests.
+			l.logger.Errorf("unexpected error while reading Data frame payload: %v", err)
+			return false, err
 		}
-		buf = pool.Get(size)
-		defer pool.Put(buf)
-
-		copy((*buf)[:hSize], dataItem.h)
-		_, _ = reader.Read((*buf)[hSize:])
 	}
 
 	// Now that outgoing flow controls are checked we can replenish str's write quota
@@ -1032,7 +1021,14 @@ func (l *loopyWriter) processData() (bool, error) {
 	if dataItem.onEachWrite != nil {
 		dataItem.onEachWrite()
 	}
-	if err := l.framer.fr.WriteData(dataItem.streamID, endStream, (*buf)[:size]); err != nil {
+	err := l.framer.writeData(dataItem.streamID, endStream, l.writeBuf)
+	reader.Discard(dSize)
+	if cap(l.writeBuf) > maxWriteBufSize {
+		l.writeBuf = nil
+	} else {
+		clear(l.writeBuf)
+	}
+	if err != nil {
 		return false, err
 	}
 	str.bytesOutStanding += size
@@ -1040,7 +1036,7 @@ func (l *loopyWriter) processData() (bool, error) {
 	dataItem.h = dataItem.h[hSize:]
 
 	if remainingBytes == 0 { // All the data from that message was written out.
-		_ = reader.Close()
+		reader.Close()
 		str.itl.dequeue()
 	}
 	if str.itl.isEmpty() {

vendor/google.golang.org/grpc/internal/transport/flowcontrol.go

@@ -28,7 +28,7 @@ import (
 // writeQuota is a soft limit on the amount of data a stream can
 // schedule before some of it is written out.
 type writeQuota struct {
-	quota int32
+	_ noCopy
 	// get waits on read from when quota goes less than or equal to zero.
 	// replenish writes on it when quota goes positive again.
 	ch chan struct{}
@@ -38,16 +38,17 @@ type writeQuota struct {
 	// It is implemented as a field so that it can be updated
 	// by tests.
 	replenish func(n int)
+	quota     int32
 }
 
-func newWriteQuota(sz int32, done <-chan struct{}) *writeQuota {
-	w := &writeQuota{
-		quota: sz,
-		ch:    make(chan struct{}, 1),
-		done:  done,
-	}
+// init allows a writeQuota to be initialized in-place, which is useful for
+// resetting a buffer or for avoiding a heap allocation when the buffer is
+// embedded in another struct.
+func (w *writeQuota) init(sz int32, done <-chan struct{}) {
+	w.quota = sz
+	w.ch = make(chan struct{}, 1)
+	w.done = done
 	w.replenish = w.realReplenish
-	return w
 }
 
 func (w *writeQuota) get(sz int32) error {
@@ -67,9 +68,9 @@ func (w *writeQuota) get(sz int32) error {
 
 func (w *writeQuota) realReplenish(n int) {
 	sz := int32(n)
-	a := atomic.AddInt32(&w.quota, sz)
-	b := a - sz
-	if b <= 0 && a > 0 {
+	newQuota := atomic.AddInt32(&w.quota, sz)
+	previousQuota := newQuota - sz
+	if previousQuota <= 0 && newQuota > 0 {
 		select {
 		case w.ch <- struct{}{}:
 		default:

vendor/google.golang.org/grpc/internal/transport/handler_server.go

@@ -50,7 +50,7 @@ import (
 // NewServerHandlerTransport returns a ServerTransport handling gRPC from
 // inside an http.Handler, or writes an HTTP error to w and returns an error.
 // It requires that the http Server supports HTTP/2.
-func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats []stats.Handler, bufferPool mem.BufferPool) (ServerTransport, error) {
+func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats stats.Handler, bufferPool mem.BufferPool) (ServerTransport, error) {
 	if r.Method != http.MethodPost {
 		w.Header().Set("Allow", http.MethodPost)
 		msg := fmt.Sprintf("invalid gRPC request method %q", r.Method)
@@ -170,7 +170,7 @@ type serverHandlerTransport struct {
 	// TODO make sure this is consistent across handler_server and http2_server
 	contentSubtype string
 
-	stats  []stats.Handler
+	stats  stats.Handler
 	logger *grpclog.PrefixLogger
 
 	bufferPool mem.BufferPool
@@ -274,14 +274,14 @@ func (ht *serverHandlerTransport) writeStatus(s *ServerStream, st *status.Status
 		}
 	})
 
-	if err == nil { // transport has not been closed
+	if err == nil && ht.stats != nil { // transport has not been closed
 		// Note: The trailer fields are compressed with hpack after this call returns.
 		// No WireLength field is set here.
-		for _, sh := range ht.stats {
-			sh.HandleRPC(s.Context(), &stats.OutTrailer{
-				Trailer: s.trailer.Copy(),
-			})
-		}
+		s.hdrMu.Lock()
+		ht.stats.HandleRPC(s.Context(), &stats.OutTrailer{
+			Trailer: s.trailer.Copy(),
+		})
+		s.hdrMu.Unlock()
 	}
 	ht.Close(errors.New("finished writing status"))
 	return err
@@ -372,19 +372,23 @@ func (ht *serverHandlerTransport) writeHeader(s *ServerStream, md metadata.MD) e
 		ht.rw.(http.Flusher).Flush()
 	})
 
-	if err == nil {
-		for _, sh := range ht.stats {
-			// Note: The header fields are compressed with hpack after this call returns.
-			// No WireLength field is set here.
-			sh.HandleRPC(s.Context(), &stats.OutHeader{
-				Header:      md.Copy(),
-				Compression: s.sendCompress,
-			})
-		}
+	if err == nil && ht.stats != nil {
+		// Note: The header fields are compressed with hpack after this call returns.
+		// No WireLength field is set here.
+		ht.stats.HandleRPC(s.Context(), &stats.OutHeader{
+			Header:      md.Copy(),
+			Compression: s.sendCompress,
+		})
 	}
 	return err
 }
 
+func (ht *serverHandlerTransport) adjustWindow(*ServerStream, uint32) {
+}
+
+func (ht *serverHandlerTransport) updateWindow(*ServerStream, uint32) {
+}
+
 func (ht *serverHandlerTransport) HandleStreams(ctx context.Context, startStream func(*ServerStream)) {
 	// With this transport type there will be exactly 1 stream: this HTTP request.
 	var cancel context.CancelFunc
@@ -409,11 +413,9 @@ func (ht *serverHandlerTransport) HandleStreams(ctx context.Context, startStream
 	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
 	req := ht.req
 	s := &ServerStream{
-		Stream: &Stream{
+		Stream: Stream{
 			id:             0, // irrelevant
 			ctx:            ctx,
-			requestRead:    func(int) {},
-			buf:            newRecvBuffer(),
 			method:         req.URL.Path,
 			recvCompress:   req.Header.Get("grpc-encoding"),
 			contentSubtype: ht.contentSubtype,
@@ -422,9 +424,11 @@ func (ht *serverHandlerTransport) HandleStreams(ctx context.Context, startStream
 		st:               ht,
 		headerWireLength: 0, // won't have access to header wire length until golang/go#18997.
 	}
-	s.trReader = &transportReader{
-		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf},
-		windowHandler: func(int) {},
+	s.Stream.buf.init()
+	s.readRequester = s
+	s.trReader = transportReader{
+		reader:        recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: &s.buf},
+		windowHandler: s,
 	}
 
 	// readerDone is closed when the Body.Read-ing goroutine exits.

vendor/google.golang.org/grpc/internal/transport/http2_client.go

@@ -44,6 +44,7 @@ import (
 	"google.golang.org/grpc/internal/grpcutil"
 	imetadata "google.golang.org/grpc/internal/metadata"
 	"google.golang.org/grpc/internal/proxyattributes"
+	istats "google.golang.org/grpc/internal/stats"
 	istatus "google.golang.org/grpc/internal/status"
 	isyscall "google.golang.org/grpc/internal/syscall"
 	"google.golang.org/grpc/internal/transport/networktype"
@@ -105,7 +106,7 @@ type http2Client struct {
 	kp               keepalive.ClientParameters
 	keepaliveEnabled bool
 
-	statsHandlers []stats.Handler
+	statsHandler stats.Handler
 
 	initialWindowSize int32
 
@@ -335,14 +336,14 @@ func NewHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		writerDone:            make(chan struct{}),
 		goAway:                make(chan struct{}),
 		keepaliveDone:         make(chan struct{}),
-		framer:                newFramer(conn, writeBufSize, readBufSize, opts.SharedWriteBuffer, maxHeaderListSize),
+		framer:                newFramer(conn, writeBufSize, readBufSize, opts.SharedWriteBuffer, maxHeaderListSize, opts.BufferPool),
 		fc:                    &trInFlow{limit: uint32(icwz)},
 		scheme:                scheme,
 		activeStreams:         make(map[uint32]*ClientStream),
 		isSecure:              isSecure,
 		perRPCCreds:           perRPCCreds,
 		kp:                    kp,
-		statsHandlers:         opts.StatsHandlers,
+		statsHandler:          istats.NewCombinedHandler(opts.StatsHandlers...),
 		initialWindowSize:     initialWindowSize,
 		nextID:                1,
 		maxConcurrentStreams:  defaultMaxStreamsClient,
@@ -369,7 +370,7 @@ func NewHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 		})
 	t.logger = prefixLoggerForClientTransport(t)
 	// Add peer information to the http2client context.
-	t.ctx = peer.NewContext(t.ctx, t.getPeer())
+	t.ctx = peer.NewContext(t.ctx, t.Peer())
 
 	if md, ok := addr.Metadata.(*metadata.MD); ok {
 		t.md = *md
@@ -386,15 +387,14 @@ func NewHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 			updateFlowControl: t.updateFlowControl,
 		}
 	}
-	for _, sh := range t.statsHandlers {
-		t.ctx = sh.TagConn(t.ctx, &stats.ConnTagInfo{
+	if t.statsHandler != nil {
+		t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{
 			RemoteAddr: t.remoteAddr,
 			LocalAddr:  t.localAddr,
 		})
-		connBegin := &stats.ConnBegin{
+		t.statsHandler.HandleConn(t.ctx, &stats.ConnBegin{
 			Client: true,
-		}
-		sh.HandleConn(t.ctx, connBegin)
+		})
 	}
 	if t.keepaliveEnabled {
 		t.kpDormancyCond = sync.NewCond(&t.mu)
@@ -478,45 +478,40 @@ func NewHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts
 	return t, nil
 }
 
-func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *ClientStream {
+func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr, handler stats.Handler) *ClientStream {
 	// TODO(zhaoq): Handle uint32 overflow of Stream.id.
 	s := &ClientStream{
-		Stream: &Stream{
+		Stream: Stream{
 			method:         callHdr.Method,
 			sendCompress:   callHdr.SendCompress,
-			buf:            newRecvBuffer(),
 			contentSubtype: callHdr.ContentSubtype,
 		},
-		ct:         t,
-		done:       make(chan struct{}),
-		headerChan: make(chan struct{}),
-		doneFunc:   callHdr.DoneFunc,
-	}
-	s.wq = newWriteQuota(defaultWriteQuota, s.done)
-	s.requestRead = func(n int) {
-		t.adjustWindow(s, uint32(n))
+		ct:           t,
+		done:         make(chan struct{}),
+		headerChan:   make(chan struct{}),
+		doneFunc:     callHdr.DoneFunc,
+		statsHandler: handler,
 	}
+	s.Stream.buf.init()
+	s.Stream.wq.init(defaultWriteQuota, s.done)
+	s.readRequester = s
 	// The client side stream context should have exactly the same life cycle with the user provided context.
 	// That means, s.ctx should be read-only. And s.ctx is done iff ctx is done.
 	// So we use the original context here instead of creating a copy.
 	s.ctx = ctx
-	s.trReader = &transportReader{
-		reader: &recvBufferReader{
-			ctx:     s.ctx,
-			ctxDone: s.ctx.Done(),
-			recv:    s.buf,
-			closeStream: func(err error) {
-				s.Close(err)
-			},
-		},
-		windowHandler: func(n int) {
-			t.updateWindow(s, uint32(n))
+	s.trReader = transportReader{
+		reader: recvBufferReader{
+			ctx:          s.ctx,
+			ctxDone:      s.ctx.Done(),
+			recv:         &s.buf,
+			clientStream: s,
 		},
+		windowHandler: s,
 	}
 	return s
 }
 
-func (t *http2Client) getPeer() *peer.Peer {
+func (t *http2Client) Peer() *peer.Peer {
 	return &peer.Peer{
 		Addr:      t.remoteAddr,
 		AuthInfo:  t.authInfo, // Can be nil
@@ -556,6 +551,22 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 	// Make the slice of certain predictable size to reduce allocations made by append.
 	hfLen := 7 // :method, :scheme, :path, :authority, content-type, user-agent, te
 	hfLen += len(authData) + len(callAuthData)
+	registeredCompressors := t.registeredCompressors
+	if callHdr.AcceptedCompressors != nil {
+		registeredCompressors = *callHdr.AcceptedCompressors
+	}
+	if callHdr.PreviousAttempts > 0 {
+		hfLen++
+	}
+	if callHdr.SendCompress != "" {
+		hfLen++
+	}
+	if registeredCompressors != "" {
+		hfLen++
+	}
+	if _, ok := ctx.Deadline(); ok {
+		hfLen++
+	}
 	headerFields := make([]hpack.HeaderField, 0, hfLen)
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":method", Value: "POST"})
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":scheme", Value: t.scheme})
@@ -568,7 +579,6 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-previous-rpc-attempts", Value: strconv.Itoa(callHdr.PreviousAttempts)})
 	}
 
-	registeredCompressors := t.registeredCompressors
 	if callHdr.SendCompress != "" {
 		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-encoding", Value: callHdr.SendCompress})
 		// Include the outgoing compressor name when compressor is not registered
@@ -735,8 +745,8 @@ func (e NewStreamError) Error() string {
 
 // NewStream creates a stream and registers it into the transport as "active"
 // streams.  All non-nil errors returned will be *NewStreamError.
-func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*ClientStream, error) {
-	ctx = peer.NewContext(ctx, t.getPeer())
+func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr, handler stats.Handler) (*ClientStream, error) {
+	ctx = peer.NewContext(ctx, t.Peer())
 
 	// ServerName field of the resolver returned address takes precedence over
 	// Host field of CallHdr to determine the :authority header. This is because,
@@ -772,7 +782,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*ClientS
 	if err != nil {
 		return nil, &NewStreamError{Err: err, AllowTransparentRetry: false}
 	}
-	s := t.newStream(ctx, callHdr)
+	s := t.newStream(ctx, callHdr, handler)
 	cleanup := func(err error) {
 		if s.swapState(streamDone) == streamDone {
 			// If it was already done, return.
@@ -811,7 +821,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*ClientS
 			return nil
 		},
 		onOrphaned: cleanup,
-		wq:         s.wq,
+		wq:         &s.wq,
 	}
 	firstTry := true
 	var ch chan struct{}
@@ -842,7 +852,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*ClientS
 		transportDrainRequired = t.nextID > MaxStreamID
 
 		s.id = hdr.streamID
-		s.fc = &inFlow{limit: uint32(t.initialWindowSize)}
+		s.fc = inFlow{limit: uint32(t.initialWindowSize)}
 		t.activeStreams[s.id] = s
 		t.mu.Unlock()
 
@@ -893,27 +903,23 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*ClientS
 			return nil, &NewStreamError{Err: ErrConnClosing, AllowTransparentRetry: true}
 		}
 	}
-	if len(t.statsHandlers) != 0 {
+	if s.statsHandler != nil {
 		header, ok := metadata.FromOutgoingContext(ctx)
 		if ok {
 			header.Set("user-agent", t.userAgent)
 		} else {
 			header = metadata.Pairs("user-agent", t.userAgent)
 		}
-		for _, sh := range t.statsHandlers {
-			// Note: The header fields are compressed with hpack after this call returns.
-			// No WireLength field is set here.
-			// Note: Creating a new stats object to prevent pollution.
-			outHeader := &stats.OutHeader{
-				Client:      true,
-				FullMethod:  callHdr.Method,
-				RemoteAddr:  t.remoteAddr,
-				LocalAddr:   t.localAddr,
-				Compression: callHdr.SendCompress,
-				Header:      header,
-			}
-			sh.HandleRPC(s.ctx, outHeader)
-		}
+		// Note: The header fields are compressed with hpack after this call returns.
+		// No WireLength field is set here.
+		s.statsHandler.HandleRPC(s.ctx, &stats.OutHeader{
+			Client:      true,
+			FullMethod:  callHdr.Method,
+			RemoteAddr:  t.remoteAddr,
+			LocalAddr:   t.localAddr,
+			Compression: callHdr.SendCompress,
+			Header:      header,
+		})
 	}
 	if transportDrainRequired {
 		if t.logger.V(logLevel) {
@@ -990,6 +996,9 @@ func (t *http2Client) closeStream(s *ClientStream, err error, rst bool, rstCode
 // accessed anymore.
 func (t *http2Client) Close(err error) {
 	t.conn.SetWriteDeadline(time.Now().Add(time.Second * 10))
+	// For background on the deadline value chosen here, see
+	// https://github.com/grpc/grpc-go/issues/8425#issuecomment-3057938248 .
+	t.conn.SetReadDeadline(time.Now().Add(time.Second))
 	t.mu.Lock()
 	// Make sure we only close once.
 	if t.state == closing {
@@ -1051,11 +1060,10 @@ func (t *http2Client) Close(err error) {
 	for _, s := range streams {
 		t.closeStream(s, err, false, http2.ErrCodeNo, st, nil, false)
 	}
-	for _, sh := range t.statsHandlers {
-		connEnd := &stats.ConnEnd{
+	if t.statsHandler != nil {
+		t.statsHandler.HandleConn(t.ctx, &stats.ConnEnd{
 			Client: true,
-		}
-		sh.HandleConn(t.ctx, connEnd)
+		})
 	}
 }
 
@@ -1166,7 +1174,7 @@ func (t *http2Client) updateFlowControl(n uint32) {
 	})
 }
 
-func (t *http2Client) handleData(f *http2.DataFrame) {
+func (t *http2Client) handleData(f *parsedDataFrame) {
 	size := f.Header().Length
 	var sendBDPPing bool
 	if t.bdpEst != nil {
@@ -1210,22 +1218,15 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			t.closeStream(s, io.EOF, true, http2.ErrCodeFlowControl, status.New(codes.Internal, err.Error()), nil, false)
 			return
 		}
+		dataLen := f.data.Len()
 		if f.Header().Flags.Has(http2.FlagDataPadded) {
-			if w := s.fc.onRead(size - uint32(len(f.Data()))); w > 0 {
+			if w := s.fc.onRead(size - uint32(dataLen)); w > 0 {
 				t.controlBuf.put(&outgoingWindowUpdate{s.id, w})
 			}
 		}
-		// TODO(bradfitz, zhaoq): A copy is required here because there is no
-		// guarantee f.Data() is consumed before the arrival of next frame.
-		// Can this copy be eliminated?
-		if len(f.Data()) > 0 {
-			pool := t.bufferPool
-			if pool == nil {
-				// Note that this is only supposed to be nil in tests. Otherwise, stream is
-				// always initialized with a BufferPool.
-				pool = mem.DefaultBufferPool()
-			}
-			s.write(recvMsg{buffer: mem.Copy(f.Data(), pool)})
+		if dataLen > 0 {
+			f.data.Ref()
+			s.write(recvMsg{buffer: f.data})
 		}
 	}
 	// The server has closed the stream without sending trailers.  Record that
@@ -1465,17 +1466,14 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		contentTypeErr = "malformed header: missing HTTP content-type"
 		grpcMessage    string
 		recvCompress   string
-		httpStatusCode *int
 		httpStatusErr  string
-		rawStatusCode  = codes.Unknown
+		// the code from the grpc-status header, if present
+		grpcStatusCode = codes.Unknown
 		// headerError is set if an error is encountered while parsing the headers
 		headerError string
+		httpStatus  string
 	)
 
-	if initialHeader {
-		httpStatusErr = "malformed header: missing HTTP status"
-	}
-
 	for _, hf := range frame.Fields {
 		switch hf.Name {
 		case "content-type":
@@ -1491,35 +1489,15 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		case "grpc-status":
 			code, err := strconv.ParseInt(hf.Value, 10, 32)
 			if err != nil {
-				se := status.New(codes.Internal, fmt.Sprintf("transport: malformed grpc-status: %v", err))
+				se := status.New(codes.Unknown, fmt.Sprintf("transport: malformed grpc-status: %v", err))
 				t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
 				return
 			}
-			rawStatusCode = codes.Code(uint32(code))
+			grpcStatusCode = codes.Code(uint32(code))
 		case "grpc-message":
 			grpcMessage = decodeGrpcMessage(hf.Value)
 		case ":status":
-			if hf.Value == "200" {
-				httpStatusErr = ""
-				statusCode := 200
-				httpStatusCode = &statusCode
-				break
-			}
-
-			c, err := strconv.ParseInt(hf.Value, 10, 32)
-			if err != nil {
-				se := status.New(codes.Internal, fmt.Sprintf("transport: malformed http-status: %v", err))
-				t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
-				return
-			}
-			statusCode := int(c)
-			httpStatusCode = &statusCode
-
-			httpStatusErr = fmt.Sprintf(
-				"unexpected HTTP status code received from server: %d (%s)",
-				statusCode,
-				http.StatusText(statusCode),
-			)
+			httpStatus = hf.Value
 		default:
 			if isReservedHeader(hf.Name) && !isWhitelistedHeader(hf.Name) {
 				break
@@ -1534,25 +1512,52 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		}
 	}
 
-	if !isGRPC || httpStatusErr != "" {
-		var code = codes.Internal // when header does not include HTTP status, return INTERNAL
-
-		if httpStatusCode != nil {
+	// If a non-gRPC response is received, then evaluate the HTTP status to
+	// process the response and close the stream.
+	// In case http status doesn't provide any error information (status : 200),
+	// then evalute response code to be Unknown.
+	if !isGRPC {
+		var grpcErrorCode = codes.Internal
+		if httpStatus == "" {
+			httpStatusErr = "malformed header: missing HTTP status"
+		} else {
+			// Parse the status codes (e.g. "200", 404").
+			statusCode, err := strconv.Atoi(httpStatus)
+			if err != nil {
+				se := status.New(grpcErrorCode, fmt.Sprintf("transport: malformed http-status: %v", err))
+				t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
+				return
+			}
+			if statusCode >= 100 && statusCode < 200 {
+				if endStream {
+					se := status.New(codes.Internal, fmt.Sprintf(
+						"protocol error: informational header with status code %d must not have END_STREAM set", statusCode))
+					t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
+				}
+				// In case of informational headers, return.
+				return
+			}
+			httpStatusErr = fmt.Sprintf(
+				"unexpected HTTP status code received from server: %d (%s)",
+				statusCode,
+				http.StatusText(statusCode),
+			)
 			var ok bool
-			code, ok = HTTPStatusConvTab[*httpStatusCode]
+			grpcErrorCode, ok = HTTPStatusConvTab[statusCode]
 			if !ok {
-				code = codes.Unknown
+				grpcErrorCode = codes.Unknown
 			}
 		}
 		var errs []string
 		if httpStatusErr != "" {
 			errs = append(errs, httpStatusErr)
 		}
+
 		if contentTypeErr != "" {
 			errs = append(errs, contentTypeErr)
 		}
-		// Verify the HTTP response is a 200.
-		se := status.New(code, strings.Join(errs, "; "))
+
+		se := status.New(grpcErrorCode, strings.Join(errs, "; "))
 		t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
 		return
 	}
@@ -1583,22 +1588,20 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		}
 	}
 
-	for _, sh := range t.statsHandlers {
+	if s.statsHandler != nil {
 		if !endStream {
-			inHeader := &stats.InHeader{
+			s.statsHandler.HandleRPC(s.ctx, &stats.InHeader{
 				Client:      true,
 				WireLength:  int(frame.Header().Length),
 				Header:      metadata.MD(mdata).Copy(),
 				Compression: s.recvCompress,
-			}
-			sh.HandleRPC(s.ctx, inHeader)
+			})
 		} else {
-			inTrailer := &stats.InTrailer{
+			s.statsHandler.HandleRPC(s.ctx, &stats.InTrailer{
 				Client:     true,
 				WireLength: int(frame.Header().Length),
 				Trailer:    metadata.MD(mdata).Copy(),
-			}
-			sh.HandleRPC(s.ctx, inTrailer)
+			})
 		}
 	}
 
@@ -1606,7 +1609,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		return
 	}
 
-	status := istatus.NewWithProto(rawStatusCode, grpcMessage, mdata[grpcStatusDetailsBinHeader])
+	status := istatus.NewWithProto(grpcStatusCode, grpcMessage, mdata[grpcStatusDetailsBinHeader])
 
 	// If client received END_STREAM from server while stream was still active,
 	// send RST_STREAM.
@@ -1653,7 +1656,7 @@ func (t *http2Client) reader(errCh chan<- error) {
 	// loop to keep reading incoming messages on this transport.
 	for {
 		t.controlBuf.throttle()
-		frame, err := t.framer.fr.ReadFrame()
+		frame, err := t.framer.readFrame()
 		if t.keepaliveEnabled {
 			atomic.StoreInt64(&t.lastRead, time.Now().UnixNano())
 		}
@@ -1668,7 +1671,7 @@ func (t *http2Client) reader(errCh chan<- error) {
 				if s != nil {
 					// use error detail to provide better err message
 					code := http2ErrConvTab[se.Code]
-					errorDetail := t.framer.fr.ErrorDetail()
+					errorDetail := t.framer.errorDetail()
 					var msg string
 					if errorDetail != nil {
 						msg = errorDetail.Error()
@@ -1686,8 +1689,9 @@ func (t *http2Client) reader(errCh chan<- error) {
 		switch frame := frame.(type) {
 		case *http2.MetaHeadersFrame:
 			t.operateHeaders(frame)
-		case *http2.DataFrame:
+		case *parsedDataFrame:
 			t.handleData(frame)
+			frame.data.Free()
 		case *http2.RSTStreamFrame:
 			t.handleRSTStream(frame)
 		case *http2.SettingsFrame:
@@ -1807,8 +1811,6 @@ func (t *http2Client) socketMetrics() *channelz.EphemeralSocketMetrics {
 	}
 }
 
-func (t *http2Client) RemoteAddr() net.Addr { return t.remoteAddr }
-
 func (t *http2Client) incrMsgSent() {
 	if channelz.IsOn() {
 		t.channelz.SocketMetrics.MessagesSent.Add(1)

vendor/google.golang.org/grpc/internal/transport/http2_server.go

@@ -35,6 +35,8 @@ import (
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	"google.golang.org/protobuf/proto"
+
 	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/grpclog"
 	"google.golang.org/grpc/internal/grpcutil"
@@ -42,7 +44,6 @@ import (
 	istatus "google.golang.org/grpc/internal/status"
 	"google.golang.org/grpc/internal/syscall"
 	"google.golang.org/grpc/mem"
-	"google.golang.org/protobuf/proto"
 
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
@@ -86,7 +87,7 @@ type http2Server struct {
 	// updates, reset streams, and various settings) to the controller.
 	controlBuf *controlBuffer
 	fc         *trInFlow
-	stats      []stats.Handler
+	stats      stats.Handler
 	// Keepalive and max-age parameters for the server.
 	kp keepalive.ServerParameters
 	// Keepalive enforcement policy.
@@ -168,7 +169,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 	if config.MaxHeaderListSize != nil {
 		maxHeaderListSize = *config.MaxHeaderListSize
 	}
-	framer := newFramer(conn, writeBufSize, readBufSize, config.SharedWriteBuffer, maxHeaderListSize)
+	framer := newFramer(conn, writeBufSize, readBufSize, config.SharedWriteBuffer, maxHeaderListSize, config.BufferPool)
 	// Send initial settings as connection preface to client.
 	isettings := []http2.Setting{{
 		ID:  http2.SettingMaxFrameSize,
@@ -260,7 +261,7 @@ func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport,
 		fc:                &trInFlow{limit: uint32(icwz)},
 		state:             reachable,
 		activeStreams:     make(map[uint32]*ServerStream),
-		stats:             config.StatsHandlers,
+		stats:             config.StatsHandler,
 		kp:                kp,
 		idle:              time.Now(),
 		kep:               kep,
@@ -390,16 +391,15 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 	}
 	t.maxStreamID = streamID
 
-	buf := newRecvBuffer()
 	s := &ServerStream{
-		Stream: &Stream{
-			id:  streamID,
-			buf: buf,
-			fc:  &inFlow{limit: uint32(t.initialWindowSize)},
+		Stream: Stream{
+			id: streamID,
+			fc: inFlow{limit: uint32(t.initialWindowSize)},
 		},
 		st:               t,
 		headerWireLength: int(frame.Header().Length),
 	}
+	s.Stream.buf.init()
 	var (
 		// if false, content-type was missing or invalid
 		isGRPC      = false
@@ -479,13 +479,7 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 		if t.logger.V(logLevel) {
 			t.logger.Infof("Aborting the stream early: %v", errMsg)
 		}
-		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     http.StatusBadRequest,
-			streamID:       streamID,
-			contentSubtype: s.contentSubtype,
-			status:         status.New(codes.Internal, errMsg),
-			rst:            !frame.StreamEnded(),
-		})
+		t.writeEarlyAbort(streamID, s.contentSubtype, status.New(codes.Internal, errMsg), http.StatusBadRequest, !frame.StreamEnded())
 		return nil
 	}
 
@@ -499,23 +493,11 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 		return nil
 	}
 	if !isGRPC {
-		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     http.StatusUnsupportedMediaType,
-			streamID:       streamID,
-			contentSubtype: s.contentSubtype,
-			status:         status.Newf(codes.InvalidArgument, "invalid gRPC request content-type %q", contentType),
-			rst:            !frame.StreamEnded(),
-		})
+		t.writeEarlyAbort(streamID, s.contentSubtype, status.Newf(codes.InvalidArgument, "invalid gRPC request content-type %q", contentType), http.StatusUnsupportedMediaType, !frame.StreamEnded())
 		return nil
 	}
 	if headerError != nil {
-		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     http.StatusBadRequest,
-			streamID:       streamID,
-			contentSubtype: s.contentSubtype,
-			status:         headerError,
-			rst:            !frame.StreamEnded(),
-		})
+		t.writeEarlyAbort(streamID, s.contentSubtype, headerError, http.StatusBadRequest, !frame.StreamEnded())
 		return nil
 	}
 
@@ -569,13 +551,7 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 		if t.logger.V(logLevel) {
 			t.logger.Infof("Aborting the stream early: %v", errMsg)
 		}
-		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     http.StatusMethodNotAllowed,
-			streamID:       streamID,
-			contentSubtype: s.contentSubtype,
-			status:         status.New(codes.Internal, errMsg),
-			rst:            !frame.StreamEnded(),
-		})
+		t.writeEarlyAbort(streamID, s.contentSubtype, status.New(codes.Internal, errMsg), http.StatusMethodNotAllowed, !frame.StreamEnded())
 		s.cancel()
 		return nil
 	}
@@ -590,27 +566,16 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 			if !ok {
 				stat = status.New(codes.PermissionDenied, err.Error())
 			}
-			t.controlBuf.put(&earlyAbortStream{
-				httpStatus:     http.StatusOK,
-				streamID:       s.id,
-				contentSubtype: s.contentSubtype,
-				status:         stat,
-				rst:            !frame.StreamEnded(),
-			})
+			t.writeEarlyAbort(s.id, s.contentSubtype, stat, http.StatusOK, !frame.StreamEnded())
 			return nil
 		}
 	}
 
 	if s.ctx.Err() != nil {
 		t.mu.Unlock()
+		st := status.New(codes.DeadlineExceeded, context.DeadlineExceeded.Error())
 		// Early abort in case the timeout was zero or so low it already fired.
-		t.controlBuf.put(&earlyAbortStream{
-			httpStatus:     http.StatusOK,
-			streamID:       s.id,
-			contentSubtype: s.contentSubtype,
-			status:         status.New(codes.DeadlineExceeded, context.DeadlineExceeded.Error()),
-			rst:            !frame.StreamEnded(),
-		})
+		t.writeEarlyAbort(s.id, s.contentSubtype, st, http.StatusOK, !frame.StreamEnded())
 		return nil
 	}
 
@@ -640,25 +605,21 @@ func (t *http2Server) operateHeaders(ctx context.Context, frame *http2.MetaHeade
 		t.channelz.SocketMetrics.StreamsStarted.Add(1)
 		t.channelz.SocketMetrics.LastRemoteStreamCreatedTimestamp.Store(time.Now().UnixNano())
 	}
-	s.requestRead = func(n int) {
-		t.adjustWindow(s, uint32(n))
-	}
+	s.readRequester = s
 	s.ctxDone = s.ctx.Done()
-	s.wq = newWriteQuota(defaultWriteQuota, s.ctxDone)
-	s.trReader = &transportReader{
-		reader: &recvBufferReader{
+	s.Stream.wq.init(defaultWriteQuota, s.ctxDone)
+	s.trReader = transportReader{
+		reader: recvBufferReader{
 			ctx:     s.ctx,
 			ctxDone: s.ctxDone,
-			recv:    s.buf,
-		},
-		windowHandler: func(n int) {
-			t.updateWindow(s, uint32(n))
+			recv:    &s.buf,
 		},
+		windowHandler: s,
 	}
 	// Register the stream with loopy.
 	t.controlBuf.put(&registerStream{
 		streamID: s.id,
-		wq:       s.wq,
+		wq:       &s.wq,
 	})
 	handle(s)
 	return nil
@@ -674,7 +635,7 @@ func (t *http2Server) HandleStreams(ctx context.Context, handle func(*ServerStre
 	}()
 	for {
 		t.controlBuf.throttle()
-		frame, err := t.framer.fr.ReadFrame()
+		frame, err := t.framer.readFrame()
 		atomic.StoreInt64(&t.lastRead, time.Now().UnixNano())
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
@@ -711,8 +672,9 @@ func (t *http2Server) HandleStreams(ctx context.Context, handle func(*ServerStre
 				})
 				continue
 			}
-		case *http2.DataFrame:
+		case *parsedDataFrame:
 			t.handleData(frame)
+			frame.data.Free()
 		case *http2.RSTStreamFrame:
 			t.handleRSTStream(frame)
 		case *http2.SettingsFrame:
@@ -792,7 +754,7 @@ func (t *http2Server) updateFlowControl(n uint32) {
 
 }
 
-func (t *http2Server) handleData(f *http2.DataFrame) {
+func (t *http2Server) handleData(f *parsedDataFrame) {
 	size := f.Header().Length
 	var sendBDPPing bool
 	if t.bdpEst != nil {
@@ -837,22 +799,15 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 			t.closeStream(s, true, http2.ErrCodeFlowControl, false)
 			return
 		}
+		dataLen := f.data.Len()
 		if f.Header().Flags.Has(http2.FlagDataPadded) {
-			if w := s.fc.onRead(size - uint32(len(f.Data()))); w > 0 {
+			if w := s.fc.onRead(size - uint32(dataLen)); w > 0 {
 				t.controlBuf.put(&outgoingWindowUpdate{s.id, w})
 			}
 		}
-		// TODO(bradfitz, zhaoq): A copy is required here because there is no
-		// guarantee f.Data() is consumed before the arrival of next frame.
-		// Can this copy be eliminated?
-		if len(f.Data()) > 0 {
-			pool := t.bufferPool
-			if pool == nil {
-				// Note that this is only supposed to be nil in tests. Otherwise, stream is
-				// always initialized with a BufferPool.
-				pool = mem.DefaultBufferPool()
-			}
-			s.write(recvMsg{buffer: mem.Copy(f.Data(), pool)})
+		if dataLen > 0 {
+			f.data.Ref()
+			s.write(recvMsg{buffer: f.data})
 		}
 	}
 	if f.StreamEnded() {
@@ -979,13 +934,12 @@ func appendHeaderFieldsFromMD(headerFields []hpack.HeaderField, md metadata.MD)
 	return headerFields
 }
 
-func (t *http2Server) checkForHeaderListSize(it any) bool {
+func (t *http2Server) checkForHeaderListSize(hf []hpack.HeaderField) bool {
 	if t.maxSendHeaderListSize == nil {
 		return true
 	}
-	hdrFrame := it.(*headerFrame)
 	var sz int64
-	for _, f := range hdrFrame.hf {
+	for _, f := range hf {
 		if sz += int64(f.Size()); sz > int64(*t.maxSendHeaderListSize) {
 			if t.logger.V(logLevel) {
 				t.logger.Infof("Header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
@@ -996,6 +950,42 @@ func (t *http2Server) checkForHeaderListSize(it any) bool {
 	return true
 }
 
+// writeEarlyAbort sends an early abort response with the given HTTP status and
+// gRPC status. If the header list size exceeds the peer's limit, it sends a
+// RST_STREAM instead.
+func (t *http2Server) writeEarlyAbort(streamID uint32, contentSubtype string, stat *status.Status, httpStatus uint32, rst bool) {
+	hf := []hpack.HeaderField{
+		{Name: ":status", Value: strconv.Itoa(int(httpStatus))},
+		{Name: "content-type", Value: grpcutil.ContentType(contentSubtype)},
+		{Name: "grpc-status", Value: strconv.Itoa(int(stat.Code()))},
+		{Name: "grpc-message", Value: encodeGrpcMessage(stat.Message())},
+	}
+	if p := istatus.RawStatusProto(stat); len(p.GetDetails()) > 0 {
+		stBytes, err := proto.Marshal(p)
+		if err != nil {
+			t.logger.Errorf("Failed to marshal rpc status: %s, error: %v", pretty.ToJSON(p), err)
+		}
+		if err == nil {
+			hf = append(hf, hpack.HeaderField{Name: grpcStatusDetailsBinHeader, Value: encodeBinHeader(stBytes)})
+		}
+	}
+	success, _ := t.controlBuf.executeAndPut(func() bool {
+		return t.checkForHeaderListSize(hf)
+	}, &earlyAbortStream{
+		streamID: streamID,
+		rst:      rst,
+		hf:       hf,
+	})
+	if !success {
+		t.controlBuf.put(&cleanupStream{
+			streamID: streamID,
+			rst:      true,
+			rstCode:  http2.ErrCodeInternal,
+			onWrite:  func() {},
+		})
+	}
+}
+
 func (t *http2Server) streamContextErr(s *ServerStream) error {
 	select {
 	case <-t.done:
@@ -1051,7 +1041,7 @@ func (t *http2Server) writeHeaderLocked(s *ServerStream) error {
 		endStream: false,
 		onWrite:   t.setResetPingStrikes,
 	}
-	success, err := t.controlBuf.executeAndPut(func() bool { return t.checkForHeaderListSize(hf) }, hf)
+	success, err := t.controlBuf.executeAndPut(func() bool { return t.checkForHeaderListSize(hf.hf) }, hf)
 	if !success {
 		if err != nil {
 			return err
@@ -1059,14 +1049,13 @@ func (t *http2Server) writeHeaderLocked(s *ServerStream) error {
 		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
-	for _, sh := range t.stats {
+	if t.stats != nil {
 		// Note: Headers are compressed with hpack after this call returns.
 		// No WireLength field is set here.
-		outHeader := &stats.OutHeader{
+		t.stats.HandleRPC(s.Context(), &stats.OutHeader{
 			Header:      s.header.Copy(),
 			Compression: s.sendCompress,
-		}
-		sh.HandleRPC(s.Context(), outHeader)
+		})
 	}
 	return nil
 }
@@ -1122,7 +1111,7 @@ func (t *http2Server) writeStatus(s *ServerStream, st *status.Status) error {
 	}
 
 	success, err := t.controlBuf.executeAndPut(func() bool {
-		return t.checkForHeaderListSize(trailingHeader)
+		return t.checkForHeaderListSize(trailingHeader.hf)
 	}, nil)
 	if !success {
 		if err != nil {
@@ -1134,10 +1123,10 @@ func (t *http2Server) writeStatus(s *ServerStream, st *status.Status) error {
 	// Send a RST_STREAM after the trailers if the client has not already half-closed.
 	rst := s.getState() == streamActive
 	t.finishStream(s, rst, http2.ErrCodeNo, trailingHeader, true)
-	for _, sh := range t.stats {
+	if t.stats != nil {
 		// Note: The trailer fields are compressed with hpack after this call returns.
 		// No WireLength field is set here.
-		sh.HandleRPC(s.Context(), &stats.OutTrailer{
+		t.stats.HandleRPC(s.Context(), &stats.OutTrailer{
 			Trailer: s.trailer.Copy(),
 		})
 	}
@@ -1305,7 +1294,8 @@ func (t *http2Server) Close(err error) {
 // deleteStream deletes the stream s from transport's active streams.
 func (t *http2Server) deleteStream(s *ServerStream, eosReceived bool) {
 	t.mu.Lock()
-	if _, ok := t.activeStreams[s.id]; ok {
+	_, isActive := t.activeStreams[s.id]
+	if isActive {
 		delete(t.activeStreams, s.id)
 		if len(t.activeStreams) == 0 {
 			t.idle = time.Now()
@@ -1313,7 +1303,7 @@ func (t *http2Server) deleteStream(s *ServerStream, eosReceived bool) {
 	}
 	t.mu.Unlock()
 
-	if channelz.IsOn() {
+	if isActive && channelz.IsOn() {
 		if eosReceived {
 			t.channelz.SocketMetrics.StreamsSucceeded.Add(1)
 		} else {
@@ -1353,10 +1343,10 @@ func (t *http2Server) closeStream(s *ServerStream, rst bool, rstCode http2.ErrCo
 	// called to interrupt the potential blocking on other goroutines.
 	s.cancel()
 
-	oldState := s.swapState(streamDone)
-	if oldState == streamDone {
-		return
-	}
+	// We can't return early even if the stream's state is "done" as the state
+	// might have been set by the `finishStream` method. Deleting the stream via
+	// `finishStream` can get blocked on flow control.
+	s.swapState(streamDone)
 	t.deleteStream(s, eosReceived)
 
 	t.controlBuf.put(&cleanupStream{

vendor/google.golang.org/grpc/internal/transport/http_util.go

@@ -25,7 +25,6 @@ import (
 	"fmt"
 	"io"
 	"math"
-	"net"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -37,6 +36,7 @@ import (
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/mem"
 )
 
 const (
@@ -300,11 +300,11 @@ type bufWriter struct {
 	buf       []byte
 	offset    int
 	batchSize int
-	conn      net.Conn
+	conn      io.Writer
 	err       error
 }
 
-func newBufWriter(conn net.Conn, batchSize int, pool *sync.Pool) *bufWriter {
+func newBufWriter(conn io.Writer, batchSize int, pool *sync.Pool) *bufWriter {
 	w := &bufWriter{
 		batchSize: batchSize,
 		conn:      conn,
@@ -388,15 +388,29 @@ func toIOError(err error) error {
 	return ioError{error: err}
 }
 
+type parsedDataFrame struct {
+	http2.FrameHeader
+	data mem.Buffer
+}
+
+func (df *parsedDataFrame) StreamEnded() bool {
+	return df.FrameHeader.Flags.Has(http2.FlagDataEndStream)
+}
+
 type framer struct {
-	writer *bufWriter
-	fr     *http2.Framer
+	writer    *bufWriter
+	fr        *http2.Framer
+	headerBuf []byte // cached slice for framer headers to reduce heap allocs.
+	reader    io.Reader
+	dataFrame parsedDataFrame // Cached data frame to avoid heap allocations.
+	pool      mem.BufferPool
+	errDetail error
 }
 
 var writeBufferPoolMap = make(map[int]*sync.Pool)
 var writeBufferMutex sync.Mutex
 
-func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, sharedWriteBuffer bool, maxHeaderListSize uint32) *framer {
+func newFramer(conn io.ReadWriter, writeBufferSize, readBufferSize int, sharedWriteBuffer bool, maxHeaderListSize uint32, memPool mem.BufferPool) *framer {
 	if writeBufferSize < 0 {
 		writeBufferSize = 0
 	}
@@ -412,6 +426,8 @@ func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, sharedWriteBu
 	f := &framer{
 		writer: w,
 		fr:     http2.NewFramer(w, r),
+		reader: r,
+		pool:   memPool,
 	}
 	f.fr.SetMaxReadFrameSize(http2MaxFrameLen)
 	// Opt-in to Frame reuse API on framer to reduce garbage.
@@ -422,6 +438,146 @@ func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, sharedWriteBu
 	return f
 }
 
+// writeData writes a DATA frame.
+//
+// It is the caller's responsibility not to violate the maximum frame size.
+func (f *framer) writeData(streamID uint32, endStream bool, data [][]byte) error {
+	var flags http2.Flags
+	if endStream {
+		flags = http2.FlagDataEndStream
+	}
+	length := uint32(0)
+	for _, d := range data {
+		length += uint32(len(d))
+	}
+	// TODO: Replace the header write with the framer API being added in
+	// https://github.com/golang/go/issues/66655.
+	f.headerBuf = append(f.headerBuf[:0],
+		byte(length>>16),
+		byte(length>>8),
+		byte(length),
+		byte(http2.FrameData),
+		byte(flags),
+		byte(streamID>>24),
+		byte(streamID>>16),
+		byte(streamID>>8),
+		byte(streamID))
+	if _, err := f.writer.Write(f.headerBuf); err != nil {
+		return err
+	}
+	for _, d := range data {
+		if _, err := f.writer.Write(d); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// readFrame reads a single frame. The returned Frame is only valid
+// until the next call to readFrame.
+func (f *framer) readFrame() (any, error) {
+	f.errDetail = nil
+	fh, err := f.fr.ReadFrameHeader()
+	if err != nil {
+		f.errDetail = f.fr.ErrorDetail()
+		return nil, err
+	}
+	// Read the data frame directly from the underlying io.Reader to avoid
+	// copies.
+	if fh.Type == http2.FrameData {
+		err = f.readDataFrame(fh)
+		return &f.dataFrame, err
+	}
+	fr, err := f.fr.ReadFrameForHeader(fh)
+	if err != nil {
+		f.errDetail = f.fr.ErrorDetail()
+		return nil, err
+	}
+	return fr, err
+}
+
+// errorDetail returns a more detailed error of the last error
+// returned by framer.readFrame. For instance, if readFrame
+// returns a StreamError with code PROTOCOL_ERROR, errorDetail
+// will say exactly what was invalid. errorDetail is not guaranteed
+// to return a non-nil value.
+// errorDetail is reset after the next call to readFrame.
+func (f *framer) errorDetail() error {
+	return f.errDetail
+}
+
+func (f *framer) readDataFrame(fh http2.FrameHeader) (err error) {
+	if fh.StreamID == 0 {
+		// DATA frames MUST be associated with a stream. If a
+		// DATA frame is received whose stream identifier
+		// field is 0x0, the recipient MUST respond with a
+		// connection error (Section 5.4.1) of type
+		// PROTOCOL_ERROR.
+		f.errDetail = errors.New("DATA frame with stream ID 0")
+		return http2.ConnectionError(http2.ErrCodeProtocol)
+	}
+	// Converting a *[]byte to a mem.SliceBuffer incurs a heap allocation. This
+	// conversion is performed by mem.NewBuffer. To avoid the extra allocation
+	// a []byte is allocated directly if required and cast to a mem.SliceBuffer.
+	var buf []byte
+	// poolHandle is the pointer returned by the buffer pool (if it's used.).
+	var poolHandle *[]byte
+	useBufferPool := !mem.IsBelowBufferPoolingThreshold(int(fh.Length))
+	if useBufferPool {
+		poolHandle = f.pool.Get(int(fh.Length))
+		buf = *poolHandle
+		defer func() {
+			if err != nil {
+				f.pool.Put(poolHandle)
+			}
+		}()
+	} else {
+		buf = make([]byte, int(fh.Length))
+	}
+	if fh.Flags.Has(http2.FlagDataPadded) {
+		if fh.Length == 0 {
+			return io.ErrUnexpectedEOF
+		}
+		// This initial 1-byte read can be inefficient for unbuffered readers,
+		// but it allows the rest of the payload to be read directly to the
+		// start of the destination slice. This makes it easy to return the
+		// original slice back to the buffer pool.
+		if _, err := io.ReadFull(f.reader, buf[:1]); err != nil {
+			return err
+		}
+		padSize := buf[0]
+		buf = buf[:len(buf)-1]
+		if int(padSize) > len(buf) {
+			// If the length of the padding is greater than the
+			// length of the frame payload, the recipient MUST
+			// treat this as a connection error.
+			// Filed: https://github.com/http2/http2-spec/issues/610
+			f.errDetail = errors.New("pad size larger than data payload")
+			return http2.ConnectionError(http2.ErrCodeProtocol)
+		}
+		if _, err := io.ReadFull(f.reader, buf); err != nil {
+			return err
+		}
+		buf = buf[:len(buf)-int(padSize)]
+	} else if _, err := io.ReadFull(f.reader, buf); err != nil {
+		return err
+	}
+
+	f.dataFrame.FrameHeader = fh
+	if useBufferPool {
+		// Update the handle to point to the (potentially re-sliced) buf.
+		*poolHandle = buf
+		f.dataFrame.data = mem.NewBuffer(poolHandle, f.pool)
+	} else {
+		f.dataFrame.data = mem.SliceBuffer(buf)
+	}
+	return nil
+}
+
+func (df *parsedDataFrame) Header() http2.FrameHeader {
+	return df.FrameHeader
+}
+
 func getWriteBufferPool(size int) *sync.Pool {
 	writeBufferMutex.Lock()
 	defer writeBufferMutex.Unlock()

vendor/google.golang.org/grpc/internal/transport/server_stream.go

@@ -32,7 +32,7 @@ import (
 
 // ServerStream implements streaming functionality for a gRPC server.
 type ServerStream struct {
-	*Stream // Embed for common stream functionality.
+	Stream // Embed for common stream functionality.
 
 	st      internalServerTransport
 	ctxDone <-chan struct{} // closed at the end of stream.  Cache of ctx.Done() (for performance)
@@ -43,12 +43,13 @@ type ServerStream struct {
 	// Holds compressor names passed in grpc-accept-encoding metadata from the
 	// client.
 	clientAdvertisedCompressors string
-	headerWireLength            int
 
 	// hdrMu protects outgoing header and trailer metadata.
 	hdrMu      sync.Mutex
 	header     metadata.MD // the outgoing header metadata.  Updated by WriteHeader.
 	headerSent atomic.Bool // atomically set when the headers are sent out.
+
+	headerWireLength int
 }
 
 // Read reads an n byte message from the input stream.
@@ -178,3 +179,11 @@ func (s *ServerStream) SetTrailer(md metadata.MD) error {
 	s.hdrMu.Unlock()
 	return nil
 }
+
+func (s *ServerStream) requestRead(n int) {
+	s.st.adjustWindow(s, uint32(n))
+}
+
+func (s *ServerStream) updateWindow(n int) {
+	s.st.updateWindow(s, uint32(n))
+}

vendor/google.golang.org/grpc/internal/transport/transport.go

@@ -68,11 +68,11 @@ type recvBuffer struct {
 	err     error
 }
 
-func newRecvBuffer() *recvBuffer {
-	b := &recvBuffer{
-		c: make(chan recvMsg, 1),
-	}
-	return b
+// init allows a recvBuffer to be initialized in-place, which is useful
+// for resetting a buffer or for avoiding a heap allocation when the buffer
+// is embedded in another struct.
+func (b *recvBuffer) init() {
+	b.c = make(chan recvMsg, 1)
 }
 
 func (b *recvBuffer) put(r recvMsg) {
@@ -123,12 +123,13 @@ func (b *recvBuffer) get() <-chan recvMsg {
 // recvBufferReader implements io.Reader interface to read the data from
 // recvBuffer.
 type recvBufferReader struct {
-	closeStream func(error) // Closes the client transport stream with the given error and nil trailer metadata.
-	ctx         context.Context
-	ctxDone     <-chan struct{} // cache of ctx.Done() (for performance).
-	recv        *recvBuffer
-	last        mem.Buffer // Stores the remaining data in the previous calls.
-	err         error
+	_            noCopy
+	clientStream *ClientStream // The client transport stream is closed with a status representing ctx.Err() and nil trailer metadata.
+	ctx          context.Context
+	ctxDone      <-chan struct{} // cache of ctx.Done() (for performance).
+	recv         *recvBuffer
+	last         mem.Buffer // Stores the remaining data in the previous calls.
+	err          error
 }
 
 func (r *recvBufferReader) ReadMessageHeader(header []byte) (n int, err error) {
@@ -139,7 +140,7 @@ func (r *recvBufferReader) ReadMessageHeader(header []byte) (n int, err error) {
 		n, r.last = mem.ReadUnsafe(header, r.last)
 		return n, nil
 	}
-	if r.closeStream != nil {
+	if r.clientStream != nil {
 		n, r.err = r.readMessageHeaderClient(header)
 	} else {
 		n, r.err = r.readMessageHeader(header)
@@ -164,7 +165,7 @@ func (r *recvBufferReader) Read(n int) (buf mem.Buffer, err error) {
 		}
 		return buf, nil
 	}
-	if r.closeStream != nil {
+	if r.clientStream != nil {
 		buf, r.err = r.readClient(n)
 	} else {
 		buf, r.err = r.read(n)
@@ -209,7 +210,7 @@ func (r *recvBufferReader) readMessageHeaderClient(header []byte) (n int, err er
 		// TODO: delaying ctx error seems like a unnecessary side effect. What
 		// we really want is to mark the stream as done, and return ctx error
 		// faster.
-		r.closeStream(ContextErr(r.ctx.Err()))
+		r.clientStream.Close(ContextErr(r.ctx.Err()))
 		m := <-r.recv.get()
 		return r.readMessageHeaderAdditional(m, header)
 	case m := <-r.recv.get():
@@ -236,7 +237,7 @@ func (r *recvBufferReader) readClient(n int) (buf mem.Buffer, err error) {
 		// TODO: delaying ctx error seems like a unnecessary side effect. What
 		// we really want is to mark the stream as done, and return ctx error
 		// faster.
-		r.closeStream(ContextErr(r.ctx.Err()))
+		r.clientStream.Close(ContextErr(r.ctx.Err()))
 		m := <-r.recv.get()
 		return r.readAdditional(m, n)
 	case m := <-r.recv.get():
@@ -285,27 +286,32 @@ const (
 
 // Stream represents an RPC in the transport layer.
 type Stream struct {
-	id           uint32
 	ctx          context.Context // the associated context of the stream
 	method       string          // the associated RPC method of the stream
 	recvCompress string
 	sendCompress string
-	buf          *recvBuffer
-	trReader     *transportReader
-	fc           *inFlow
-	wq           *writeQuota
 
-	// Callback to state application's intentions to read data. This
-	// is used to adjust flow control, if needed.
-	requestRead func(int)
-
-	state streamState
+	readRequester readRequester
 
 	// contentSubtype is the content-subtype for requests.
 	// this must be lowercase or the behavior is undefined.
 	contentSubtype string
 
 	trailer metadata.MD // the key-value map of trailer metadata.
+
+	// Non-pointer fields are at the end to optimize GC performance.
+	state    streamState
+	id       uint32
+	buf      recvBuffer
+	trReader transportReader
+	fc       inFlow
+	wq       writeQuota
+}
+
+// readRequester is used to state application's intentions to read data. This
+// is used to adjust flow control, if needed.
+type readRequester interface {
+	requestRead(int)
 }
 
 func (s *Stream) swapState(st streamState) streamState {
@@ -355,7 +361,7 @@ func (s *Stream) ReadMessageHeader(header []byte) (err error) {
 	if er := s.trReader.er; er != nil {
 		return er
 	}
-	s.requestRead(len(header))
+	s.readRequester.requestRead(len(header))
 	for len(header) != 0 {
 		n, err := s.trReader.ReadMessageHeader(header)
 		header = header[n:]
@@ -372,13 +378,29 @@ func (s *Stream) ReadMessageHeader(header []byte) (err error) {
 	return nil
 }
 
+// ceil returns the ceil after dividing the numerator and denominator while
+// avoiding integer overflows.
+func ceil(numerator, denominator int) int {
+	if numerator == 0 {
+		return 0
+	}
+	return (numerator-1)/denominator + 1
+}
+
 // Read reads n bytes from the wire for this stream.
 func (s *Stream) read(n int) (data mem.BufferSlice, err error) {
 	// Don't request a read if there was an error earlier
 	if er := s.trReader.er; er != nil {
 		return nil, er
 	}
-	s.requestRead(n)
+	// gRPC Go accepts data frames with a maximum length of 16KB. Larger
+	// messages must be split into multiple frames. We pre-allocate the
+	// buffer to avoid resizing during the read loop, but cap the initial
+	// capacity to 128 frames (2MB) to prevent over-allocation or panics
+	// when reading extremely large streams.
+	allocCap := min(ceil(n, http2MaxFrameLen), 128)
+	data = make(mem.BufferSlice, 0, allocCap)
+	s.readRequester.requestRead(n)
 	for n != 0 {
 		buf, err := s.trReader.Read(n)
 		var bufLen int
@@ -401,16 +423,34 @@ func (s *Stream) read(n int) (data mem.BufferSlice, err error) {
 	return data, nil
 }
 
+// noCopy may be embedded into structs which must not be copied
+// after the first use.
+//
+// See https://golang.org/issues/8005#issuecomment-190753527
+// for details.
+type noCopy struct {
+}
+
+func (*noCopy) Lock()   {}
+func (*noCopy) Unlock() {}
+
 // transportReader reads all the data available for this Stream from the transport and
 // passes them into the decoder, which converts them into a gRPC message stream.
 // The error is io.EOF when the stream is done or another non-nil error if
 // the stream broke.
 type transportReader struct {
-	reader *recvBufferReader
+	_ noCopy
 	// The handler to control the window update procedure for both this
 	// particular stream and the associated transport.
-	windowHandler func(int)
+	windowHandler windowHandler
 	er            error
+	reader        recvBufferReader
+}
+
+// The handler to control the window update procedure for both this
+// particular stream and the associated transport.
+type windowHandler interface {
+	updateWindow(int)
 }
 
 func (t *transportReader) ReadMessageHeader(header []byte) (int, error) {
@@ -419,7 +459,7 @@ func (t *transportReader) ReadMessageHeader(header []byte) (int, error) {
 		t.er = err
 		return 0, err
 	}
-	t.windowHandler(n)
+	t.windowHandler.updateWindow(n)
 	return n, nil
 }
 
@@ -429,7 +469,7 @@ func (t *transportReader) Read(n int) (mem.Buffer, error) {
 		t.er = err
 		return buf, err
 	}
-	t.windowHandler(buf.Len())
+	t.windowHandler.updateWindow(buf.Len())
 	return buf, nil
 }
 
@@ -454,7 +494,7 @@ type ServerConfig struct {
 	ConnectionTimeout     time.Duration
 	Credentials           credentials.TransportCredentials
 	InTapHandle           tap.ServerInHandle
-	StatsHandlers         []stats.Handler
+	StatsHandler          stats.Handler
 	KeepaliveParams       keepalive.ServerParameters
 	KeepalivePolicy       keepalive.EnforcementPolicy
 	InitialWindowSize     int32
@@ -529,6 +569,12 @@ type CallHdr struct {
 	// outbound message.
 	SendCompress string
 
+	// AcceptedCompressors overrides the grpc-accept-encoding header for this
+	// call. When nil, the transport advertises the default set of registered
+	// compressors. A non-nil pointer overrides that value (including the empty
+	// string to advertise none).
+	AcceptedCompressors *string
+
 	// Creds specifies credentials.PerRPCCredentials for a call.
 	Creds credentials.PerRPCCredentials
 
@@ -544,9 +590,14 @@ type CallHdr struct {
 
 	DoneFunc func() // called when the stream is finished
 
-	// Authority is used to explicitly override the `:authority` header. If set,
-	// this value takes precedence over the Host field and will be used as the
-	// value for the `:authority` header.
+	// Authority is used to explicitly override the `:authority` header.
+	//
+	// This value comes from one of two sources:
+	// 1. The `CallAuthority` call option, if specified by the user.
+	// 2. An override provided by the LB picker (e.g. xDS authority rewriting).
+	//
+	// The `CallAuthority` call option always takes precedence over the LB
+	// picker override.
 	Authority string
 }
 
@@ -566,7 +617,7 @@ type ClientTransport interface {
 	GracefulClose()
 
 	// NewStream creates a Stream for an RPC.
-	NewStream(ctx context.Context, callHdr *CallHdr) (*ClientStream, error)
+	NewStream(ctx context.Context, callHdr *CallHdr, handler stats.Handler) (*ClientStream, error)
 
 	// Error returns a channel that is closed when some I/O error
 	// happens. Typically the caller should have a goroutine to monitor
@@ -584,8 +635,9 @@ type ClientTransport interface {
 	// with a human readable string with debug info.
 	GetGoAwayReason() (GoAwayReason, string)
 
-	// RemoteAddr returns the remote network address.
-	RemoteAddr() net.Addr
+	// Peer returns information about the peer associated with the Transport.
+	// The returned information includes authentication and network address details.
+	Peer() *peer.Peer
 }
 
 // ServerTransport is the common interface for all gRPC server-side transport
@@ -615,6 +667,8 @@ type internalServerTransport interface {
 	write(s *ServerStream, hdr []byte, data mem.BufferSlice, opts *WriteOptions) error
 	writeStatus(s *ServerStream, st *status.Status) error
 	incrMsgRecv()
+	adjustWindow(s *ServerStream, n uint32)
+	updateWindow(s *ServerStream, n uint32)
 }
 
 // connectionErrorf creates an ConnectionError with the specified error description.