code: func tcpTimeStamp(offset uint32) uint32 {
  	now := time.Now()
  	return uint32(now.Unix()*1000+int64(now.Nanosecond()/1e6)) + offset
  }
docs: // tcpTimeStamp returns a timestamp offset by the provided offset. This is
  // not inlined above as it's used when SYN cookies are in use and endpoint
  // is not created at the time when the SYN cookie is sent.