Validating Receipt.md

Validating a Receipt

Verify the authenticity and integrity of an App Store receipt.

Default Validation

Runs four checks in parallel: certificate chain, signature, hash, and metadata.

let result = await receipt.validate()

switch result {
case .valid:
    break
case .invalid(let error):
    print(error)
}

The validator auto-selects the Apple root certificate based on the receipt's environment.

Custom Validators

Build your own with @VerifierBuilder:

let validator = ReceiptValidator {
    X509ChainVerifier(rootCertificates: [rootCert])
    SignatureVerifier()
    HashVerifier(deviceIdentifier: deviceId)
    MetaVerifier(
        appVersionProvider: { Bundle.main.appVersion },
        bundleIdentifierProvider: { Bundle.main.bundleIdentifier }
    )
}

let result = await validator.validate(receipt)

Include or exclude any verifier. They run in parallel via TaskGroup — if any fails, the rest are cancelled.

Built-in Verifiers

Verifier	What it checks
X509ChainVerifier	Certificate chain against Apple root (swift-certificates)
SecChainVerifier	Certificate chain via Security.framework
SignatureVerifier	PKCS#7 signature (swift-crypto)
SecSignatureVerifier	PKCS#7 signature via Security.framework
HashVerifier	SHA-1 hash: device ID + opaque value + bundle ID
MetaVerifier	Bundle identifier and app version match

X509/Signature variants are async. Sec variants use Security.framework and work in blocking contexts.

Error Types

• ReceiptValidatorError — invalid structure, missing root certificate, missing device identifier
• ChainVerificationError — certificate data invalid, chain validation failed, revocation check failed
• SignatureVerificationError — invalid key, invalid signature
• HashVerificationError — missing device identifier, hash mismatch
• MetaVerificationError — bundle identifier mismatch, version mismatch

See doc:Architecture for how the validation layer fits into the overall design.