Function hpke_kem::AuthDecap

pub fn AuthDecap(
    alg: KEM, 
    enc: &ByteSeq, 
    skR: &PrivateKey, 
    pkS: &PublicKey
) -> Result<SharedSecret, HpkeError>

def AuthDecap(enc, skR, pkS):
  pkE = DeserializePublicKey(enc)
  dh = concat(DH(skR, pkE), DH(skR, pkS))

  pkRm = SerializePublicKey(pk(skR))
  pkSm = SerializePublicKey(pkS)
  kem_context = concat(enc, pkRm, pkSm)

  shared_secret = ExtractAndExpand(dh, kem_context)
  return shared_secret