int secp256k1_ec_seckey_verify(const secp256k1_context* ctx, const unsigned char *seckey) {
    secp256k1_scalar sec;
    int ret;
    int overflow;
    VERIFY_CHECK(ctx != NULL);
    ARG_CHECK(seckey != NULL);

    secp256k1_scalar_set_b32(&sec, seckey, &overflow);
    ret = !overflow && !secp256k1_scalar_is_zero(&sec);
    secp256k1_scalar_clear(&sec);
    return ret;
}