Source: https://fyno.docs.pageloop.ai/sd-ks/totp/swift-sdk

# TOTP Swift SDK

The **Fyno TOTP SDK for iOS** provides secure Time-based One-Time Password (TOTP) generation and tenant management. It supports tenant enrollment, secure secret storage using the iOS Keychain, configurable TOTP parameters, and OTP generation compliant with **RFC 6238**.

> **Module Name:** `FynoTOTP`\
> **Minimum iOS Version:** iOS 13\
> **Target iOS Version:** iOS 16+\
> **Language:** Swift

## Table of Contents

1. [Installation](#installation)
2. [Core Components](#core-components)
3. [API Reference](#api-reference)
4. [Usage Examples](#usage-examples)
5. [Data Models](#data-models)
6. [Error Handling](#error-handling)
7. [Security Considerations](#security-considerations)

## Installation

### CocoaPods

Add the dependency to your `Podfile`:

```ruby
pod 'FynoTOTP'
```

Then run:

```bash
pod install
```

## Core Components

### FynoTOTP Class

The main entry point for all SDK operations.

**Responsibilities:**

- SDK initialization
- Tenant registration and revocation
- Secure secret storage using Keychain
- TOTP generation

**Initializer:**

```swift
let fynoTotp = FynoTOTP()
```

## API Reference

### initFynoConfig

Initializes the SDK with workspace and user identifiers.

```swift
func initFynoConfig(
    wsid: String,
    distinctId: String,
    completion: @escaping (Result<Void, Error>) -> Void
)
```

### registerTenant

Registers a tenant and securely stores the TOTP secret.

```swift
func registerTenant(
    tenantId: String,
    tenantLabel: String,
    totpToken: String,
    completion: @escaping (Result<Void, Error>) -> Void
)
```

### setConfig

Sets the TOTP configuration for a tenant.

```swift
func setConfig(
    tenantId: String,
    config: TotpConfig,
    completion: @escaping (Result<Void, Error>) -> Void
)
```

### getTotp

Generates and retrieves the current TOTP code.

```swift
func getTotp(
    tenantId: String,
    completion: @escaping (Result<String?, Error>) -> Void
)
```

### deleteTenantData

Deletes all tenant data and the stored secret.

```swift
func deleteTenantData(tenantId: String)
```

### fetchActiveTenants

```swift
Fetches the active tenants.

func fetchActiveTenants(
    completion: @escaping (Result<[ActiveTenant], Error>) -> Void
)
```

## Data Models

### TotpConfig

```swift
struct TotpConfig: Codable {
    let tenant_name: String
    let digits: Int
    let algorithm: String
    let period: Int
}
```

## Error Handling

### FynoError

```swift
enum FynoError: Error {
    case invalidSecret
    case invalidSecretEncoding
    case unsupportedAlgorithm
    case hashingFailed
    case base64DecodeFailed
    case secretDecodeFailed
}
```

## Security Considerations

- Secrets stored in iOS Keychain
- RFC 6238 compliant TOTP generation
- HMAC SHA1 / SHA256 / SHA512 support

## Changelog

### Version 1.0.0

- Initial iOS TOTP release