How does golang implement reflection?

Using reflection, we can get the type name, storage size and the function of the given type(such as uint64, user-defined struct and so on). Even, we can modify some fields of the given type. How does golang implement reflections? I guess the following ways:

1. Every type in golang, including user-defined type, itself has the information about type name, fields name and the function name. Golang reflection just reads these information or call the function.

2. Through some mechanism, Golang can get the type name, storage size and so on. And the type itself doesn’t have these information.

I have read the golang reflection code roughly. I guessed that golang used the second way. Who can describe the concrete implement of reflection? Or recommend me some documents? Reading all code is difficult for me.