I'm not 100% sure what parts you're referring to but I'll give it a shot. Understand that the drive shafts are the round rotating tubular shaped members that link between the tranmission and the differential. They are not at the hub.
If you are referring to the knuckle housings that contain the birfield (cv joint), there is a square headed plug that screws into the top of the knukle (ball shaped portion at end of front axle housing). You can squirt grease into the knuckle from there. Don't over fill it.. should be 2/3 to 3/4 full. Use a molybedinum fortified, NLGI no. 2 grease.
Sorry and yes its the CV joint, Sounds easy enough I just have to find the right grease over here then I guess.