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Our team brings years of experience in the digital payments industry to provide reliable services.
<?php
namespace Stripe;
abstract class WebhookSignature
{
const EXPECTED_SCHEME = 'v1';
/**
* Verifies the signature header sent by Stripe. Throws an
* Exception\SignatureVerificationException exception if the verification fails for
* any reason.
*
* @param string $payload the payload sent by Stripe
* @param string $header the contents of the signature header sent by
* Stripe
* @param string $secret secret used to generate the signature
* @param int $tolerance maximum difference allowed between the header's
* timestamp and the current time
*
* @throws Exception\SignatureVerificationException if the verification fails
*
* @return bool
*/
public static function verifyHeader($payload, $header, $secret, $tolerance = null)
{
// Extract timestamp and signatures from header
$timestamp = self::getTimestamp($header);
$signatures = self::getSignatures($header, self::EXPECTED_SCHEME);
if (-1 === $timestamp) {
throw Exception\SignatureVerificationException::factory(
'Unable to extract timestamp and signatures from header',
$payload,
$header
);
}
if (empty($signatures)) {
throw Exception\SignatureVerificationException::factory(
'No signatures found with expected scheme',
$payload,
$header
);
}
// Check if expected signature is found in list of signatures from
// header
$signedPayload = "{$timestamp}.{$payload}";
$expectedSignature = self::computeSignature($signedPayload, $secret);
$signatureFound = false;
foreach ($signatures as $signature) {
if (Util\Util::secureCompare($expectedSignature, $signature)) {
$signatureFound = true;
break;
}
}
if (!$signatureFound) {
throw Exception\SignatureVerificationException::factory(
'No signatures found matching the expected signature for payload',
$payload,
$header
);
}
// Check if timestamp is within tolerance
if (($tolerance > 0) && (\abs(\time() - $timestamp) > $tolerance)) {
throw Exception\SignatureVerificationException::factory(
'Timestamp outside the tolerance zone',
$payload,
$header
);
}
return true;
}
/**
* Extracts the timestamp in a signature header.
*
* @param string $header the signature header
*
* @return int the timestamp contained in the header, or -1 if no valid
* timestamp is found
*/
private static function getTimestamp($header)
{
$items = \explode(',', $header);
foreach ($items as $item) {
$itemParts = \explode('=', $item, 2);
if ('t' === $itemParts[0]) {
if (!\is_numeric($itemParts[1])) {
return -1;
}
return (int) ($itemParts[1]);
}
}
return -1;
}
/**
* Extracts the signatures matching a given scheme in a signature header.
*
* @param string $header the signature header
* @param string $scheme the signature scheme to look for
*
* @return array the list of signatures matching the provided scheme
*/
private static function getSignatures($header, $scheme)
{
$signatures = [];
$items = \explode(',', $header);
foreach ($items as $item) {
$itemParts = \explode('=', $item, 2);
if (\trim($itemParts[0]) === $scheme) {
$signatures[] = $itemParts[1];
}
}
return $signatures;
}
/**
* Computes the signature for a given payload and secret.
*
* The current scheme used by Stripe ("v1") is HMAC/SHA-256.
*
* @param string $payload the payload to sign
* @param string $secret the secret used to generate the signature
*
* @return string the signature as a string
*/
private static function computeSignature($payload, $secret)
{
return \hash_hmac('sha256', $payload, $secret);
}
}
How it Works
Getting started with NFC Pay is simple and quick. Register your account, add your cards, and you're ready to make payments in no time. Whether you're paying at a store, sending money to a friend, or managing your merchant transactions, NFC Pay makes it easy and secure.
Download the NFC Pay app and sign up with your email or phone number. Complete the registration process by verifying your identity, and set up your secure PIN to protect your account.
Link your debit or credit cards to your NFC Pay wallet. Simply scan your card or enter the details manually, and you’re set to load funds, shop, and pay with ease.
To pay, simply tap your phone or scan the QR code at checkout. You can also transfer money to other users with a few taps. Enjoy fast, contactless payments with top-notch security.
Security System
NFC Pay prioritizes your security with advanced features that safeguard every transaction. From SMS or email verification to end-to-end encryption, we've implemented robust measures to ensure your data is always protected. Our security systems are designed to prevent unauthorized access and provide you with a safe and reliable payment experience.
Receive instant alerts for every transaction to keep track of your account activities.
Verify your identity through our Know Your Customer process to prevent fraud and enhance security.
Dramatically supply transparent backward deliverables before caward comp internal or "organic" sources.
All your data and transactions are encrypted, ensuring that your sensitive information remains private.
Monitor unusual activity patterns to detect and prevent suspicious behavior in real-time.
Why Choice Us
With NFC Pay, you get a trusted platform backed by proven expertise and a commitment to quality. We put our customers first, offering innovative solutions tailored to your needs, ensuring every transaction is secure, swift, and seamless.
Our team brings years of experience in the digital payments industry to provide reliable services.
We prioritize excellence, ensuring that every aspect of our platform meets the highest standards.
Your needs drive our solutions, and we are dedicated to delivering a superior user experience.
We continuously evolve, integrating the latest technologies to enhance your payment experience.
Testimonial Section
Hear from our users who trust NFC Pay for their everyday transactions. Our commitment to security, ease of use, and exceptional service shines through in their experiences. See why our clients choose NFC Pay for their payment needs and how it has transformed the way they manage their finances.
App Section
Unlock the full potential of NFC Pay by downloading our app, designed to bring secure, swift, and smart transactions to your fingertips. Whether you're paying at a store, transferring money to friends, or managing your business payments, the NFC Pay app makes it effortless. Available on both iOS and Android, it's your all-in-one solution for convenient and reliable digital payments. Download now and experience the future of payments!