github.com/sagernet/quic-go@v0.43.1-beta.1/sys_conn_df_windows.go (about) 1 //go:build windows 2 3 package quic 4 5 import ( 6 "errors" 7 "syscall" 8 9 "github.com/sagernet/quic-go/internal/utils" 10 "golang.org/x/sys/windows" 11 ) 12 13 const ( 14 // IP_DONTFRAGMENT controls the Don't Fragment (DF) bit. 15 // 16 // It's the same code point for both IPv4 and IPv6 on Windows. 17 // https://microsoft.github.io/windows-docs-rs/doc/windows/Win32/Networking/WinSock/constant.IP_DONTFRAG.html 18 // https://microsoft.github.io/windows-docs-rs/doc/windows/Win32/Networking/WinSock/constant.IPV6_DONTFRAG.html 19 // 20 //nolint:stylecheck 21 IP_DONTFRAGMENT = 14 22 ) 23 24 func setDF(rawConn syscall.RawConn) (bool, error) { 25 var errDFIPv4, errDFIPv6 error 26 if err := rawConn.Control(func(fd uintptr) { 27 errDFIPv4 = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IP, IP_DONTFRAGMENT, 1) 28 errDFIPv6 = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, IP_DONTFRAGMENT, 1) 29 }); err != nil { 30 return false, err 31 } 32 switch { 33 case errDFIPv4 == nil && errDFIPv6 == nil: 34 utils.DefaultLogger.Debugf("Setting DF for IPv4 and IPv6.") 35 case errDFIPv4 == nil && errDFIPv6 != nil: 36 utils.DefaultLogger.Debugf("Setting DF for IPv4.") 37 case errDFIPv4 != nil && errDFIPv6 == nil: 38 utils.DefaultLogger.Debugf("Setting DF for IPv6.") 39 case errDFIPv4 != nil && errDFIPv6 != nil: 40 utils.DefaultLogger.Debugf("Setting DF failed for both IPv4 and IPv6.") 41 } 42 return true, nil 43 } 44 45 func isSendMsgSizeErr(err error) bool { 46 // https://docs.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2 47 return errors.Is(err, windows.WSAEMSGSIZE) 48 } 49 50 func isRecvMsgSizeErr(err error) bool { 51 // https://docs.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2 52 return errors.Is(err, windows.WSAEMSGSIZE) 53 }