| 1 |
<?php |
| 2 |
|
| 3 |
namespace IvyForms\Services\Integrations; |
| 4 |
|
| 5 |
/** |
| 6 |
* Verifies RSA-SHA256 signatures from ivyforms-middleware (Amelia-compatible). |
| 7 |
*/ |
| 8 |
class MiddlewareSignatureService |
| 9 |
{ |
| 10 |
// private const MIDDLEWARE_PUBLIC_KEY = <<<'PEM' |
| 11 |
// -----BEGIN PUBLIC KEY----- |
| 12 |
// MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuBviz1x8ocjJnoGmum6E |
| 13 |
// vBG1jz5Hnr/FNA9lYnoYVCP3P/gFm77AFP+vfl+jCLyWzB22uD8uoea/stUmP9U9 |
| 14 |
// 0bqVT5jMZorb4BoesPD8fG+iz8WzdfotRo/xatlhyZkE+9nE45BWHwZulf0ff1P8 |
| 15 |
// IKi6FLtXukqngJ+m63fJ0GelAH8KuMj6gzM1O+SSojGO+HBCdwlCcrxBal5M2x3Z |
| 16 |
// dSKBh3U+qdCtnRSahkAO3DU7O2d9U+HZWBaKUJcb0LB1pM9mUlb3oFIaxQjLNdIk |
| 17 |
// krr9L9okRlHeB1MqxfraexHRMmcrq1jawAerFIwSQrcZHGiQalbi3PKYZFEJgxqX |
| 18 |
// WQIDAQAB |
| 19 |
// -----END PUBLIC KEY----- |
| 20 |
// PEM; |
| 21 |
|
| 22 |
private const MIDDLEWARE_PUBLIC_KEY = <<<'PEM' |
| 23 |
-----BEGIN PUBLIC KEY----- |
| 24 |
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAriCZqL/Ob/3QtdBs1ZPJ |
| 25 |
QhlHOX6/21VfqSESflh1CNcMlzpX+Qgf8htcwBJfeQur1fJ1G60x1IEjZy7lvgDS |
| 26 |
s+UN2HDBIKX5tImBNafBg6WwJW7Wf0GcEyniQTqMEvJfQ3YOWJpfC4MfPlztyT/4 |
| 27 |
2nfB1tbl0RPPvfNPO4+3vjjSARUsoJqZ+H9M1urEPr75TuyuTxB8UdQaqWxWBnoY |
| 28 |
lPOfojDPlg18eWuqKeJfOvy0QcrcJBWcgLFLqrPRUXD/V04lVtOmzS4Vftafs3Ob |
| 29 |
qY3vxOh4BMuMzqtlcGZ4bB79yC6L91rBR7+Bq+HVkJsEExmcX1uWXoNJ/G+Ser1i |
| 30 |
UwIDAQAB |
| 31 |
-----END PUBLIC KEY----- |
| 32 |
PEM; |
| 33 |
|
| 34 |
/** |
| 35 |
* @param array<string, mixed> $params Token delivery POST body from middleware. |
| 36 |
*/ |
| 37 |
public function buildTokenDeliverySignatureString(array $params): string |
| 38 |
{ |
| 39 |
return '/square/authorization/token&access_token=' . (string) ($params['access_token'] ?? '') |
| 40 |
. '&expires_at=' . (string) ($params['expires_at'] ?? '') |
| 41 |
. '&refresh_token=' . (string) ($params['refresh_token'] ?? '') |
| 42 |
. '&merchant_id=' . (string) ($params['merchant_id'] ?? ''); |
| 43 |
} |
| 44 |
|
| 45 |
/** |
| 46 |
* @param array<string, mixed> $params |
| 47 |
*/ |
| 48 |
public function verifyTokenDeliverySignature(array $params): bool |
| 49 |
{ |
| 50 |
$signature = isset($params['signature']) ? (string) $params['signature'] : ''; |
| 51 |
|
| 52 |
return $this->verifySignature($this->buildTokenDeliverySignatureString($params), $signature); |
| 53 |
} |
| 54 |
|
| 55 |
/** |
| 56 |
* @param mixed $data Webhook payload data (encoded the same way middleware signs it). |
| 57 |
*/ |
| 58 |
public function verifyWebhookDataSignature($data, ?string $signature): bool |
| 59 |
{ |
| 60 |
$encoded = json_encode($data); |
| 61 |
|
| 62 |
if (!is_string($encoded)) { |
| 63 |
return false; |
| 64 |
} |
| 65 |
|
| 66 |
return $this->verifySignature($encoded, $signature ?? ''); |
| 67 |
} |
| 68 |
|
| 69 |
public function verifySignature(string $stringToVerify, string $signature): bool |
| 70 |
{ |
| 71 |
if ($stringToVerify === '' || $signature === '') { |
| 72 |
return false; |
| 73 |
} |
| 74 |
|
| 75 |
$publicKey = openssl_pkey_get_public(self::MIDDLEWARE_PUBLIC_KEY); |
| 76 |
if ($publicKey === false) { |
| 77 |
return false; |
| 78 |
} |
| 79 |
|
| 80 |
$decodedSignature = base64_decode($signature, true); |
| 81 |
if ($decodedSignature === false) { |
| 82 |
return false; |
| 83 |
} |
| 84 |
|
| 85 |
return openssl_verify($stringToVerify, $decodedSignature, $publicKey, OPENSSL_ALGO_SHA256) === 1; |
| 86 |
} |
| 87 |
} |
| 88 |
|
