Can I access files with '.complete' protection while the device is locked?

No, '.complete' protection makes files inaccessible while the device is locked or booting. Use '.completeUntilFirstUserAuthentication' if background access is required.

Should I use Keychain or File Protection for my data?

Use Keychain for small secrets like passwords, tokens, and keys. Use File Protection for larger data like documents, images, and database files.

Is there a performance cost for using iOS file encryption?

No, iOS uses dedicated hardware-accelerated AES encryption, meaning there is no perceptible performance overhead for using Data Protection APIs.

How do I apply protection to all new files in a folder?

You can set the '.protectionKey' attribute on a directory using FileManager; new files created within that directory will inherit the specified protection level.

What is the recommended default protection level for iOS app data?

The recommended default is '.completeUntilFirstUserAuthentication', which balances security and functionality by allowing background access after the first unlock.

iOS File Protection Reference

Name: iOS File Protection Reference
Author: CharlesWiltgen

byCharlesWiltgen

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233

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Mobile Development

Provides comprehensive guidance and implementation patterns for iOS hardware-accelerated file encryption and data protection APIs.

The Axiom File Protection Reference skill is a specialized knowledge base designed for iOS developers building secure, privacy-focused applications. It offers detailed technical breakdowns of iOS protection levels, ranging from complete lockdown to background-accessible modes, and provides production-ready Swift patterns for implementing encryption at rest. By offering clear decision matrices for choosing between File Protection and Keychain storage, this skill helps developers avoid common pitfalls like background access failures and 'file not accessible' errors while ensuring sensitive user data remains protected by device hardware keys.

Key Features

01Swift code patterns for writing encrypted files and managing file attributes

02233 GitHub stars

03Best practices for securing SwiftData and SQLite database files

04Comparison of iOS Data Protection levels including complete and completeUnlessOpen

05Guidance on handling background execution and device lock state transitions

06Strategic decision matrix for File Protection vs. Keychain storage

Use Cases

01Debugging permission errors and file inaccessibility during device lock states

02Selecting the appropriate protection level for sensitive health, financial, or personal data

03Configuring app-wide security policies for document and application support directories

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add charleswiltgen/axiom axiom-file-protection-ref

For use in Claude.ai and ChatGPT

Download Skill