Webhooks

import { createHmac, timingSafeEqual } from 'node:crypto'

export const verify = (rawBody, header, secret, toleranceSeconds = 300) => {
  const parts = Object.fromEntries(header.split(',').map((p) => p.split('=')))
  const timestamp = Number(parts.t)

  if (!Number.isFinite(timestamp)) return false
  if (Math.abs(Date.now() / 1000 - timestamp) > toleranceSeconds) return false

  const expected = createHmac('sha256', secret).update(`${timestamp}.${rawBody}`).digest('hex')
  const provided = Buffer.from(parts.v1 ?? '')

  return provided.length === expected.length
    && timingSafeEqual(provided, Buffer.from(expected))
}

import hashlib, hmac, time

def verify(raw_body: bytes, header: str, secret: str, tolerance: int = 300) -> bool:
    parts = dict(part.split("=", 1) for part in header.split(","))

    try:
        timestamp = int(parts["t"])
    except (KeyError, ValueError):
        return False

    if abs(time.time() - timestamp) > tolerance:
        return False

    expected = hmac.new(
        secret.encode(),
        f"{timestamp}.".encode() + raw_body,
        hashlib.sha256,
    ).hexdigest()

    return hmac.compare_digest(expected, parts.get("v1", ""))

function nylon_verify(string $rawBody, string $header, string $secret, int $tolerance = 300): bool
{
    $parts = [];
    foreach (explode(',', $header) as $part) {
        [$key, $value] = explode('=', $part, 2);
        $parts[$key] = $value;
    }

    if (!isset($parts['t'], $parts['v1'])) {
        return false;
    }

    if (abs(time() - (int) $parts['t']) > $tolerance) {
        return false;
    }

    $expected = hash_hmac('sha256', $parts['t'] . '.' . $rawBody, $secret);

    return hash_equals($expected, $parts['v1']);
}