# Cryptotokenkit

Access security tokens and smart cards using CryptoTokenKit.

- Repository: https://github.com/dpearson2699/swift-ios-skills (1266 stars)
- Category: Security
- License: see repository
- Last updated: 2026-07-31
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add dpearson2699/swift-ios-skills --skill cryptotokenkit -g -a claude-code -y`
Codex: `npx skills add dpearson2699/swift-ios-skills --skill cryptotokenkit -g -a codex -y`
Cursor: `npx skills add dpearson2699/swift-ios-skills --skill cryptotokenkit -g -a cursor -y`
Gemini CLI: `npx skills add dpearson2699/swift-ios-skills --skill cryptotokenkit -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add dpearson2699/swift-ios-skills`

## Description

Access security tokens and smart cards using CryptoTokenKit. Use when building TKTokenDriver or TKSmartCardTokenDriver extensions, communicating with smart cards via TKSmartCard/TKSmartCardSlotManager, using iOS 26+ NFC smart-card sessions, registering smart cards, querying token-backed keychain items with kSecAttrTokenID, monitoring TKTokenWatcher, or configuring certificate-based smart-card authentication.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# CryptoTokenKit

Use CryptoTokenKit for token driver extensions, smart-card communication,
token sessions, token-backed keychain integration, and certificate-based
authentication in Swift 6.3 apps.

**Platform availability:** CryptoTokenKit classes are available across Apple
platforms, but capability depends on extension point, entitlement, hardware, and
OS version. The smart-card app extension flow for login/keychain unlock is macOS.
`TKSmartCardSlotManager.default` is optional and returns `nil` unless smart-card
access is enabled. iOS/iPadOS 26+ add NFC smart-card slots and registration.

## Contents

- [Architecture Overview](#architecture-overview)
- [Token Extensions](#token-extensions)
- [Token Sessions](#token-sessions)
- [Smart Card Communication](#smart-card-communication)
- [Keychain Integration](#keychain-integration)
- [Certificate Authentication](#certificate-authentication)
- [Token Watching](#token-watching)
- [Error Handling](#error-handling)
- [Common Mistakes](#common-mistakes)
- [Review Checklist](#review-checklist)
- [References](#references)

## Architecture Overview

CryptoTokenKit bridges hardware security tokens (smart cards, USB tokens)
with authentication and keychain services. The framework has three main usage
modes:

**Smart-card token extensions** -- macOS app extensions that make a hardware
token's cryptographic items available to system login and keychain unlock. The
driver handles token lifecycle, session management, and cryptographic operations.

**Client-side token access** -- Apps query the keychain for items backed by
tokens. CryptoTokenKit exposes token items as standard keychain entries when a
token is present.

**NFC smart-card access** -- iOS/iPadOS 26+ apps create a temporary NFC smart
card slot and communicate with the presented contactless card through
`TKSmartCard`.

The rest: https://github.com/dpearson2699/swift-ios-skills/blob/HEAD/skills/cryptotokenkit/SKILL.md