"1012",
        "VK_VERSION"     => "008",
        "VK_SND_ID"      => "uid100036",
        "VK_STAMP"       => "123",
        "VK_AMOUNT"      => "100",
        "VK_CURR"        => "EUR",
        "VK_REF"         => "1232",
        "VK_MSG"         => "Test Message",
        "VK_RETURN"      => "http://localhost/payment/test/callback/seb",
        "VK_CANCEL"      => "http://localhost/payment/test/callback/seb",
        "VK_DATETIME"    => "2022-04-29T10:35:30+0300",
        "VK_LANG"        => "EST",
        "VK_ACC"         => "EE171010123456789017",
        "VK_NAME"        => "Veebimajutus",
        "VK_ENCODING"    => "UTF-8"
);
// STEP 3. Generate data to be signed
// ==================================
// Data to be signed 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) . $fields["VK_SERVICE"] .    /* 1012 */
        str_pad (mb_strlen($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) . $fields["VK_SND_ID"] .     /* uid100036 */
        str_pad (mb_strlen($fields["VK_STAMP"], "UTF-8"),   3, "0", STR_PAD_LEFT) . $fields["VK_STAMP"] .      /* 123 */
        str_pad (mb_strlen($fields["VK_AMOUNT"], "UTF-8"),  3, "0", STR_PAD_LEFT) . $fields["VK_AMOUNT"] .     /* 100 */
        str_pad (mb_strlen($fields["VK_CURR"], "UTF-8"),    3, "0", STR_PAD_LEFT) . $fields["VK_CURR"] .       /* EUR */
        str_pad (mb_strlen($fields["VK_REF"], "UTF-8"),     3, "0", STR_PAD_LEFT) . $fields["VK_REF"] .        /* 1232 */
        str_pad (mb_strlen($fields["VK_MSG"], "UTF-8"),     3, "0", STR_PAD_LEFT) . $fields["VK_MSG"] .        /* Test Message */
        str_pad (mb_strlen($fields["VK_RETURN"], "UTF-8"),  3, "0", STR_PAD_LEFT) . $fields["VK_RETURN"] .     /* http://localhost/payment/test/callback/seb */
        str_pad (mb_strlen($fields["VK_CANCEL"], "UTF-8"),  3, "0", STR_PAD_LEFT) . $fields["VK_CANCEL"] .     /* http://localhost/payment/test/callback/seb */
        str_pad (mb_strlen($fields["VK_DATETIME"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_DATETIME"];    /* 2022-04-29T10:35:30+0300 */
/* $data = "0041012003008009uid100036003123003100003EUR0041232012Test Message042http://localhost/payment/test/callback/seb042http://localhost/payment/test/callback/seb0242022-04-29T10:35:30+0300"; */
// STEP 4. Sign the data with RSA-SHA1 to generate MAC code
// ========================================================
openssl_sign ($data, $signature, $private_key, OPENSSL_ALGO_SHA1);
/* YQiDa5YOY4iHGYcaDgB4kDE+7JEpTDkl6N+rwr2rLz6Wv06Aw6ZfYfxSwHdip4+WT5HNniYjmJMEkXKJzAP7RwHalrB54wXqmSB9A7yYLJQpnSvjKwcB4qi/SG5tuavC231dLvQh6G3kxuWhq8NRwQR1S917PKPPGX25444ROXZo06f88qx5FePv/NpSx6S0FLIHMz+1adlB75DZD6zQ07MKSaT1SGVv3XC46pCUroYQ0aYSkg8cDZqkqQuoYGVGdTdW5xGYr6OxIZ1bIE2OTYGwJ/WQGf0gQ2pV0TacE3gNDnDFqYu11Zoi0VfvhubPgmRH0IP9qo81Cpw9d/dqSA== */
$fields["VK_MAC"] = base64_encode($signature);
// STEP 5. Generate POST form with payment data that will be sent to the bank
// ==========================================================================
?>
        
        Makse teostamise näidisrakendus "SEB"