Plain SIDH?

[adamierymenko]

Is it possible to do plain SIDH with this library?

I've got a case where a drop-in DH equivalent would be nice, and the keys are ephemeral and would only be used once so the reuse caveats of SIDH do not apply.

Seems all the math is there but there is no documented way to do it. Guessing the incantation is isogen2 / isoex2 and isogen3 / isoex3 for Alice and Bob respectively.

[ederoffi]

Hello and thank you for showing interest in this crate.

Currently it is indeed not possible to perform an SIDH scheme with this lib. However as you stated, the math is there. And indeed isogen an isoex are probably the way to go. However since this library was made to match the sike API for the NIST competition, we made only the part related to the SIKE scheme available.

We will follow up on this issue to make SIDH available, maybe through a specific feature to enable. We just need to make sure first that we fully match the current state of art with our implementation and if not state restrictions (first to come in mind is currently to only be able to work with power of 2 and 3 for the torsions group)