"1111", "VK_VERSION" => "008", "VK_SND_ID" => "HP", "VK_REC_ID" => "uid100052", "VK_STAMP" => "1", "VK_T_NO" => "16400", "VK_AMOUNT" => "3418.64", "VK_CURR" => "EUR", "VK_REC_ACC" => "", "VK_REC_NAME" => "", "VK_SND_ACC" => "EE152200221234567897", "VK_SND_NAME" => "Tõõgera Leõpäöldi", "VK_REF" => "13", "VK_MSG" => "My cool payment", "VK_T_DATETIME" => "2021-02-18T09:22:13+0000", "VK_ENCODING" => "UTF-8", "VK_LANG" => "EST", "VK_MAC" => "D0Tmuv9JGKtymDYflZ9bwktxoGzy/GM+Cx+UF/djqLqJlt8ZLNjtJxTbynX1oUatbW/P7b3bkfuzsTaDlqWjfc49HrjRRz/PYf4nkgJjacdYkafCoGEjYs7WLkDdS6yQslYSiLIchrziDcVwQN8Rgw5dVvWRoRMcwq21iCD+iL08u9u/n44O9i0wLVnp9RrkiyC8fIB5vZYBoXNy7NohuIfvwxe1TE5bAeFgrRzPI3SeiK+/GJe8ZjJp3ThJuSFHptnPzTVR4ZkTXeOuzxCGqALya4fwKHVma6A3FyIIDhuEICYUhHg8bP7iQxVy8I6BwynBTwu/w3MVTCxdrjRtiQ==", "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! Swedbank 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) . $fields["VK_SERVICE"] . /* 1111 */ str_pad (mb_strlen($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) . $fields["VK_SND_ID"] . /* HP */ str_pad (mb_strlen($fields["VK_REC_ID"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_REC_ID"] . /* uid100052 */ str_pad (mb_strlen($fields["VK_STAMP"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_STAMP"] . /* 1 */ str_pad (mb_strlen($fields["VK_T_NO"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_T_NO"] . /* 16400 */ str_pad (mb_strlen($fields["VK_AMOUNT"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_AMOUNT"] . /* 3418.64 */ str_pad (mb_strlen($fields["VK_CURR"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_CURR"] . /* EUR */ str_pad (mb_strlen($fields["VK_REC_ACC"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_REC_ACC"] . /* */ str_pad (mb_strlen($fields["VK_REC_NAME"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_REC_NAME"] . /* */ str_pad (mb_strlen($fields["VK_SND_ACC"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_SND_ACC"] . /* EE152200221234567897 */ str_pad (mb_strlen($fields["VK_SND_NAME"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_SND_NAME"] . /* Tõõgera Leõpäöldi */ str_pad (mb_strlen($fields["VK_REF"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_REF"] . /* 13 */ str_pad (mb_strlen($fields["VK_MSG"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_MSG"] . /* My cool payment */ str_pad (mb_strlen($fields["VK_T_DATETIME"], "UTF-8"), 3, "0", STR_PAD_LEFT) . $fields["VK_T_DATETIME"]; /* 2021-02-18T09:22:13+0000 */ /* $data = "0041111003008002HP009uid1000520011005164000073418.64003EUR000000020EE152200221234567897017Tõõgera Leõpäöldi00213015My cool payment0242021-02-18T09:22:13+0000"; */ // STEP 4. Verify the data with RSA-SHA1 // ===================================== if (openssl_verify ($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: