Friendly bindings to liboqs

See the kem::Kem and sig::Sig structs for how to use this crate.

Example: Some signed KEX

This protocol has no replay protection!

use oqs::*;
# #[cfg(all(feature = "dilithium2", feature = "kyber"))]
fn main() -> Result<()> {
oqs::init(); // Important: initialize liboqs
let sigalg = sig::Sig::new(sig::Algorithm::Dilithium2)?;
let kemalg = kem::Kem::new(kem::Algorithm::Kyber512)?;
// A's long-term secrets
let (a_sig_pk, a_sig_sk) = sigalg.keypair()?;
// B's long-term secrets
let (b_sig_pk, b_sig_sk) = sigalg.keypair()?;

// assumption: A has (a_sig_sk, a_sig_pk, b_sig_pk)
// assumption: B has (b_sig_sk, b_sig_pk, a_sig_pk)

// A -> B: kem_pk, signature
let (kem_pk, kem_sk) = kemalg.keypair()?;
let signature = sigalg.sign(kem_pk.as_ref(), &a_sig_sk)?;

// B -> A: kem_ct, signature
sigalg.verify(kem_pk.as_ref(), &signature, &a_sig_pk)?;
let (kem_ct, b_kem_ss) = kemalg.encapsulate(&kem_pk)?;
let signature = sigalg.sign(kem_ct.as_ref(), &b_sig_sk)?;

// A verifies, decapsulates, now both have kem_ss
sigalg.verify(kem_ct.as_ref(), &signature, &b_sig_pk)?;
let a_kem_ss = kemalg.decapsulate(&kem_sk, &kem_ct)?;
assert_eq!(a_kem_ss, b_kem_ss);

Ok(())
}
# #[cfg(not(all(feature = "dilithium2", feature = "kyber")))]
# fn main() {}