via NHL.com (a look at some of the other rules too inlcuding video),

Rule 67 – Handling Puck implements a minor penalty for use of the gloved hand to "conceal" the puck or prevent an opponent from playing it. Rule 76 – Face-Off implements a minor penalty for a player taking a face-off using his hand to direct the puck.

Rule 67 - Handling Puck

67.2 Minor Penalty – Player

A player shall be permitted to catch the puck out of the air but must immediately place it or knock it down to the ice. If he catches it and skates with it, either to avoid a check or to gain a territorial advantage over his opponent, a minor penalty shall be assessed for "closing his hand on the puck."

New, approved wording in italics:

Any time a player places his hand over the puck while it is on the ice in order to conceal it from or prevent an opponent from playing the puck, a minor penalty shall be assessed for "closing his hand on the puck." When this is done in his own team's goal crease area, a penalty shot shall be assessed (67.4) or a goal awarded (67.5).

A minor penalty shall be imposed on a player who, while play is in progress, picks up the puck off the ice with his hand.

Rule 76 - Face-off