crypto_kem_sntrup761_enc
int crypto_kem_sntrup761_enc(unsigned char *cstr, unsigned char *k,
crypto_kem_sntrup761_enc(cp, kemsx->kemkey, pk);
int crypto_kem_sntrup761_enc(unsigned char *cstr, unsigned char *k,
crypto_kem_sntrup761_enc(ciphertext, kem_key, client_pub);