Tom Riddle -- Who Knew?

[gelite67]

No: HPFGUIDX 126203


DD said that few people would recognize Voldemort as the young man 
who was Tom Riddle, which leads me to wonder: Who else besides DD and 
Harry do we know for certain knows that Voldemort is Tom Riddle?  

Should we assume that Harry told Ron and Hermione?

I know that Ginny, Arthur, and Molly know that Voldemort enchanted 
Ginny via the diary, but do they know the diary was Riddles' diary?

Does Hagrid know that Voldemort is Tom Riddle?  (I'm kinda surprised 
Harry hasn't asked Hagrid questions about Riddle, since Harry knows 
that Hagrid went to school with him.)

What about Snape and the other members of the order?  Do they know?

Angie