"1911",
        "VK_VERSION"     => "008",
        "VK_SND_ID"      => "EYP",
        "VK_REC_ID"      => "uid100036",
        "VK_STAMP"       => "81",
        "VK_REF"         => "819",
        "VK_MSG"         => "Vaheajatellimus 2102010013 17.02.2021 12:00",
        "VK_ENCODING"    => "UTF-8",
        "VK_LANG"        => "EST",
        "VK_MAC"         => "MbTcGiILcyaENazjAePPInVD7bctAE//SddrXvaUemfW9TEdmVjfjYib9U2me4tR4v7AT5yjoW569Fn9m7DxBWMxCQFL5UyJzGWSxx+zXwvFOGx613dJTBQNXkJLoX7pF064wTmpj6wOknt+OS0ghiyBhyTG4vfUz9iRSPzXQESForYLZSbZXRD/upQWgPHyqeiTHrlnr++mOmzW8FyF8O+GplVXkPJG5XHFWlhQpx9HwpiifYDDYompZE/g+/txg0ORYQNKNehKoEIiC/iYbVnldovGOnafd4B5khDxGasaiPV62rYtwzjwAxCY6p82Q7etdZI/HJVJg1G+Gigj+A==",
        "VK_AUTO"        => "N"
);
// STEP 3. Generate data to be verified
// ====================================
// Data to be verified is in the form of XXXYYYYY where XXX is 3 char
// zero padded length of the value and YYY the value itself
// NB! SEB expects symbol count, not byte count with UTF-8,
// so use `mb_strlen` instead of `strlen` to detect the length of a string
$data = str_pad (mb_strlen($fields["VK_SERVICE"], "UTF-8"),   3, "0", STR_PAD_LEFT) . $fields["VK_SERVICE"] .    /* 1911 */
        str_pad (mb_strlen($fields["VK_VERSION"], "UTF-8"),   3, "0", STR_PAD_LEFT) . $fields["VK_VERSION"] .    /* 008 */
        str_pad (mb_strlen($fields["VK_SND_ID"], "UTF-8"),    3, "0", STR_PAD_LEFT) . $fields["VK_SND_ID"] .     /* EYP */
        str_pad (mb_strlen($fields["VK_REC_ID"], "UTF-8"),    3, "0", STR_PAD_LEFT) . $fields["VK_REC_ID"] .     /* uid100036 */
        str_pad (mb_strlen($fields["VK_STAMP"], "UTF-8"),     3, "0", STR_PAD_LEFT) . $fields["VK_STAMP"] .      /* 81 */
        str_pad (mb_strlen($fields["VK_REF"], "UTF-8"),       3, "0", STR_PAD_LEFT) . $fields["VK_REF"] .        /* 819 */
        str_pad (mb_strlen($fields["VK_MSG"], "UTF-8"),       3, "0", STR_PAD_LEFT) . $fields["VK_MSG"];         /* Vaheajatellimus 2102010013 17.02.2021 12:00 */
/* $data = "0041911003008003EYP009uid10003600281003819043Vaheajatellimus 2102010013 17.02.2021 12:00"; */
// STEP 4. Verify the data with RSA-SHA1
// =====================================
if (openssl_verify ($data, base64_decode($fields["VK_MAC"]), $public_key) !== 1) {
    $signatureVerified = false;
}else{
    $signatureVerified = true;
}
// STEP 5. Display output of the received payment
// ==============================================
?>
    Payment results
    Payment: 
    Signature: