Well, they are building their own diesel eletrics now. We don't know if AIP equipped. But the Club-K can be fired from a torpedo tube as well as from containers. And there is a huge range of Iranian missiles, some of which may be able to be fired from a tube and carry a significant payload.
Russia Will Equip Iranian Subs with Missiles
Excerpt mentions Club-S at least. They are refurbishing the Iranian subs however.
Also, the new anti-ship missile complex Club-S with the target distance of 200 km will be installed on these subs. The refurbishing of each sub would be done under the contract which costs anywhere from $80 to $90 million.