Yes, and there are moves in the next generation to add cryptographic signatures to the satellite streams. Someone could still jam it, but they couldn't spoof it.

Tons of info starting here: https://berthub.eu/articles/posts/galileos-authentication-al...

Continued here: https://berthub.eu/articles/posts/galileos-authentication-al...

And finally here: https://berthub.eu/articles/posts/galileos-authentication-al...