Receipt Validation – Parse and Decode a Receipt with Swift

This article is part of a receipt validation series, focusing on parsing and decoding Apple receipts using Swift. It explains how to extract readable metadata from a PKCS #7 container, including bundle identifier, app version, in-app purchase receipts, and more. The guide assumes prior setup with iTunes Connect and a cryptography library like OpenSSL. It provides code examples for defining ParsedReceipt and ParsedInAppPurchaseReceipt structs, and discusses the challenges of working with low-level C types and pointers. The final goal is a parsed receipt for further validation steps like GUID hash computation and app-specific checks.