Add support for kTLS

Reference: https://gitlab.com/go-extension/tls

common/badtls/registry.go

@@ -0,0 +1,62 @@
+//go:build go1.25 && !without_badtls
+
+package badtls
+
+import (
+	"crypto/tls"
+	"net"
+	"unsafe"
+)
+
+type Methods struct {
+	readRecord                 func(c unsafe.Pointer) error
+	handlePostHandshakeMessage func(c unsafe.Pointer) error
+	writeRecordLocked          func(c unsafe.Pointer, typ uint16, data []byte) (int, error)
+
+	setErrorLocked   func(hc unsafe.Pointer, err error) error
+	decrypt          func(hc unsafe.Pointer, record []byte) ([]byte, uint8, error)
+	setTrafficSecret func(hc unsafe.Pointer, suite unsafe.Pointer, level int, secret []byte)
+	explicitNonceLen func(hc unsafe.Pointer) int
+}
+
+var methodRegistry []func(conn net.Conn) (unsafe.Pointer, *Methods, bool)
+
+func init() {
+	methodRegistry = append(methodRegistry, func(conn net.Conn) (unsafe.Pointer, *Methods, bool) {
+		tlsConn, loaded := conn.(*tls.Conn)
+		if !loaded {
+			return nil, nil, false
+		}
+		return unsafe.Pointer(tlsConn), &Methods{
+			readRecord:                 stdTLSReadRecord,
+			handlePostHandshakeMessage: stdTLSHandlePostHandshakeMessage,
+			writeRecordLocked:          stdWriteRecordLocked,
+
+			setErrorLocked:   stdSetErrorLocked,
+			decrypt:          stdDecrypt,
+			setTrafficSecret: stdSetTrafficSecret,
+			explicitNonceLen: stdExplicitNonceLen,
+		}, true
+	})
+}
+
+//go:linkname stdTLSReadRecord crypto/tls.(*Conn).readRecord
+func stdTLSReadRecord(c unsafe.Pointer) error
+
+//go:linkname stdTLSHandlePostHandshakeMessage crypto/tls.(*Conn).handlePostHandshakeMessage
+func stdTLSHandlePostHandshakeMessage(c unsafe.Pointer) error
+
+//go:linkname stdWriteRecordLocked crypto/tls.(*Conn).writeRecordLocked
+func stdWriteRecordLocked(c unsafe.Pointer, typ uint16, data []byte) (int, error)
+
+//go:linkname stdSetErrorLocked crypto/tls.(*halfConn).setErrorLocked
+func stdSetErrorLocked(hc unsafe.Pointer, err error) error
+
+//go:linkname stdDecrypt crypto/tls.(*halfConn).decrypt
+func stdDecrypt(hc unsafe.Pointer, record []byte) ([]byte, uint8, error)
+
+//go:linkname stdSetTrafficSecret crypto/tls.(*halfConn).setTrafficSecret
+func stdSetTrafficSecret(hc unsafe.Pointer, suite unsafe.Pointer, level int, secret []byte)
+
+//go:linkname stdExplicitNonceLen crypto/tls.(*halfConn).explicitNonceLen
+func stdExplicitNonceLen(hc unsafe.Pointer) int