Fix HTTP/2 transport reset with Go 1.27

transport/v2rayhttp/force_close.go

@@ -3,7 +3,6 @@ package v2rayhttp
 import (
 	"net/http"
 	"reflect"
-	"sync"
 	"unsafe"
 
 	E "github.com/sagernet/sing/common/exceptions"
@@ -11,12 +10,6 @@ import (
 	"golang.org/x/net/http2"
 )
 
-type clientConnPool struct {
-	t     *http2.Transport
-	mu    sync.Mutex
-	conns map[string][]*http2.ClientConn // key is host:port
-}
-
 type efaceWords struct {
 	typ  unsafe.Pointer
 	data unsafe.Pointer
@@ -28,20 +21,9 @@ func ResetTransport(rawTransport http.RoundTripper) http.RoundTripper {
 		transport.CloseIdleConnections()
 		return transport.Clone()
 	case *http2.Transport:
-		connPool := transportConnPool(transport)
-		p := (*clientConnPool)((*efaceWords)(unsafe.Pointer(&connPool)).data)
-		p.mu.Lock()
-		defer p.mu.Unlock()
-		for _, vv := range p.conns {
-			for _, cc := range vv {
-				cc.Close()
-			}
-		}
+		closeHTTP2Connections(transport)
 		return transport
 	default:
 		panic(E.New("unknown transport type: ", reflect.TypeOf(transport)))
 	}
 }
-
-//go:linkname transportConnPool golang.org/x/net/http2.(*Transport).connPool
-func transportConnPool(t *http2.Transport) http2.ClientConnPool

transport/v2rayhttp/force_close_go127.go

@@ -0,0 +1,55 @@
+//go:build go1.27 && badlinkname
+
+package v2rayhttp
+
+import (
+	"net/http"
+	"sync"
+	"unsafe"
+
+	"golang.org/x/net/http2"
+)
+
+// cmd/compile creates the method symbols reachable from *http.Transport's field types with
+// their package recorded when the type is first used by a declaration; a linkname pull
+// processed afterwards reuses that symbol as a package-indexed reference, which the linker's
+// -checklinkname does not inspect. This declaration must precede the linkname declarations.
+var _ *http.Transport
+
+// net/http/internal/http2.Transport
+type internalTransport struct {
+	t1       [2]uintptr // TransportConfig
+	connPool *clientConnPool
+}
+
+// net/http/internal/http2.clientConnPool
+type clientConnPool struct {
+	t     *internalTransport
+	mu    sync.Mutex
+	conns map[string][]unsafe.Pointer // key is host:port, value is []*ClientConn
+}
+
+func closeHTTP2Connections(transport *http2.Transport) {
+	h2Transport := transportFromH1Transport(transportInit(transport))
+	t := (*internalTransport)((*efaceWords)(unsafe.Pointer(&h2Transport)).data)
+	if t == nil {
+		return
+	}
+	p := t.connPool
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for _, vv := range p.conns {
+		for _, cc := range vv {
+			clientConnClose(cc)
+		}
+	}
+}
+
+//go:linkname transportInit golang.org/x/net/http2.(*Transport).init
+func transportInit(t *http2.Transport) *http.Transport
+
+//go:linkname transportFromH1Transport net/http/internal/http2_test.transportFromH1Transport
+func transportFromH1Transport(t *http.Transport) any
+
+//go:linkname clientConnClose net/http/internal/http2.(*ClientConn).Close
+func clientConnClose(cc unsafe.Pointer) error

transport/v2rayhttp/force_close_go127_stub.go

@@ -0,0 +1,9 @@
+//go:build go1.27 && !badlinkname
+
+package v2rayhttp
+
+import "golang.org/x/net/http2"
+
+func closeHTTP2Connections(transport *http2.Transport) {
+	transport.CloseIdleConnections()
+}

transport/v2rayhttp/force_close_legacy.go

@@ -0,0 +1,31 @@
+//go:build !go1.27
+
+package v2rayhttp
+
+import (
+	"sync"
+	"unsafe"
+
+	"golang.org/x/net/http2"
+)
+
+type clientConnPool struct {
+	t     *http2.Transport
+	mu    sync.Mutex
+	conns map[string][]*http2.ClientConn // key is host:port
+}
+
+func closeHTTP2Connections(transport *http2.Transport) {
+	connPool := transportConnPool(transport)
+	p := (*clientConnPool)((*efaceWords)(unsafe.Pointer(&connPool)).data)
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for _, vv := range p.conns {
+		for _, cc := range vv {
+			cc.Close()
+		}
+	}
+}
+
+//go:linkname transportConnPool golang.org/x/net/http2.(*Transport).connPool
+func transportConnPool(t *http2.Transport) http2.ClientConnPool