encrypt

static VALUE
ossl_pkcs7_s_encrypt(int argc, VALUE *argv, VALUE klass)
{
    VALUE certs, data, cipher, flags;
    STACK_OF(X509) *x509s;
    BIO *in;
    const EVP_CIPHER *ciph;
    int flg, status = 0;
    VALUE ret;
    PKCS7 *p7;

    rb_scan_args(argc, argv, "22", &certs, &data, &cipher, &flags);
    if(NIL_P(cipher)){
#if !defined(OPENSSL_NO_RC2)
        ciph = EVP_rc2_40_cbc();
#elif !defined(OPENSSL_NO_DES)
        ciph = EVP_des_ede3_cbc();
#elif !defined(OPENSSL_NO_RC2)
        ciph = EVP_rc2_40_cbc();
#elif !defined(OPENSSL_NO_AES)
        ciph = EVP_EVP_aes_128_cbc();
#else
        ossl_raise(ePKCS7Error, "Must specify cipher");
#endif

    }
    else ciph = ossl_evp_get_cipherbyname(cipher);
    flg = NIL_P(flags) ? 0 : NUM2INT(flags);
    ret = NewPKCS7(cPKCS7);
    in = ossl_obj2bio(&data);
    x509s = ossl_protect_x509_ary2sk(certs, &status);
    if(status){
        BIO_free(in);
        rb_jump_tag(status);
    }
    if(!(p7 = PKCS7_encrypt(x509s, in, (EVP_CIPHER*)ciph, flg))){
        BIO_free(in);
        sk_X509_pop_free(x509s, X509_free);
        ossl_raise(ePKCS7Error, NULL);
    }
    BIO_free(in);
    SetPKCS7(ret, p7);
    ossl_pkcs7_set_data(ret, data);
    sk_X509_pop_free(x509s, X509_free);

    return ret;
}