Soul Link says:
Enchant Creature
Whenever enchanted creature deals damage, you gain that much life.
Whenever enchanted creature is dealt damage, you gain that much life.
If the enchanted creature is blocking, does the player gain life from the both the dealing of damage and the takng of damage at the same time? I would think so since damage is dealt simulateously and there is no reference to "either/or" in the oracle text.