The Spaniard said: "I have talked to both at different times. You never know, but I think they could be done soon."
Crouch's future has been the most in doubt, with him frequently used as a substitute and targeted by Manchester City and Portsmouth.
But Benitez continued: "Rick Parry (chief executive) told me Peter's agent wanted to talk to him about a new contract. This was one month ago or more.
"So I talked with Peter and explained my ideas, because he's aware that top sides sometimes change players. But now he is happy and Rick is talking with the agent.
"Every top side needs good players. Crouch is a different kind of striker to Fernando Torres, Andriy Voronin and Dirk Kuyt. It is really important for us to have other options, to have a player who we can use in different games."
Hyypia, 35 later this year, has figured in more games this season than many expected as Liverpool suffered defensively with injury problems.
Benitez said: "I spoke with Sami and showed him our interest. He is a very, very good professional.
"It is not just about his experience, it is about him being a good player. He has played a lot of games this season, and the idea for next season is that he can play and fight for his place in the team.
"This will be good for us. One of the positive things is that, because he is a good professional and has a lot of experience, he can give the other players advice.
"But I also think he can fight for a position against the younger players. He has been an amazing servant for this club.
"When you see a foreign player playing for the same team for 10 years, everyone must be really pleased."