sign

static VALUE
ossl_pkcs7_s_sign(int argc, VALUE *argv, VALUE klass)
{
    VALUE cert, key, data, certs, flags;
    X509 *x509;
    EVP_PKEY *pkey;
    BIO *in;
    STACK_OF(X509) *x509s;
    int flg, status = 0;
    PKCS7 *pkcs7;
    VALUE ret;

    rb_scan_args(argc, argv, "32", &cert, &key, &data, &certs, &flags);
    x509 = GetX509CertPtr(cert); /* NO NEED TO DUP */
    pkey = GetPrivPKeyPtr(key); /* NO NEED TO DUP */
    flg = NIL_P(flags) ? 0 : NUM2INT(flags);
    in = ossl_obj2bio(data);
    if(NIL_P(certs)) x509s = NULL;
    else{
        x509s = ossl_protect_x509_ary2sk(certs, &status);
        if(status){
            BIO_free(in);
            rb_jump_tag(status);
        }
    }
    if(!(pkcs7 = PKCS7_sign(x509, pkey, x509s, in, flg))){
        BIO_free(in);
        sk_X509_pop_free(x509s, X509_free);
        ossl_raise(ePKCS7Error, NULL);
    }
    WrapPKCS7(cPKCS7, ret, pkcs7);
    ossl_pkcs7_set_data(ret, data);
    ossl_pkcs7_set_err_string(ret, Qnil);
    BIO_free(in);
    sk_X509_pop_free(x509s, X509_free);

    return ret;
}