It's an interesting question the criminality of his actions may from a legal standpoint be completely independent of his status as a whistleblower or spy ( and those two categories may not be mutually exclusive either ).

Certainly he has violated his confidentiality agreements ( a civil liability ) and exposed information that is classified ( potentially a criminal liability ).

And it's possible for rational people to think that he may be doing things that are morally justifiable even if criminal. Where most people who think that investigating systematic acts of lawbreaking ( and wholesale collection of private metadata absent criminal suspicion from private companies by __any__ .gov qualifies as such on first examination ), may believe that those who bring such acts to light should be spared punishment because they are acting in defense of the greater good of society.

It is healthy for us to be reminded that our naive moral calculus is only loosely mapped to our system of laws.