kishikawakatsumi/KeychainAccess

KeychainAccess

KeychainAccess is a simple Swift wrapper for Keychain that works on iOS and macOS. Makes using Keychain APIs extremely easy and much more palatable to use in Swift.

:bulb: Features

• Simple interface
• Support access group
• Support accessibility
• Support iCloud sharing
• Support TouchID and Keychain integration (iOS 8+)
• Support Shared Web Credentials (iOS 8+)
• Works on both iOS & macOS
• watchOS and tvOS are supported
• Mac Catalyst is supported
• Swift 3, 4 and 5 compatible

:book: Usage

:eyes: See also:

• :link: iOS Example Project

:key: Basics

Saving Application Password

let keychain = Keychain(service: "com.example.github-token")
keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

Saving Internet Password

let keychain = Keychain(server: "https://github.com", protocolType: .https)
keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

:key: Instantiation

Create Keychain for Application Password

let keychain = Keychain(service: "com.example.github-token")

let keychain = Keychain(service: "com.example.github-token", accessGroup: "12ABCD3E4F.shared")

Create Keychain for Internet Password

let keychain = Keychain(server: "https://github.com", protocolType: .https)

let keychain = Keychain(server: "https://github.com", protocolType: .https, authenticationType: .htmlForm)

:key: Adding an item

subscripting

for String

keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

keychain[string: "kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

for NSData

keychain[data: "secret"] = NSData(contentsOfFile: "secret.bin")

set method

keychain.set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")

error handling

do {
    try keychain.set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
}
catch let error {
    print(error)
}

:key: Obtaining an item

subscripting

for String (If the value is NSData, attempt to convert to String)

let token = keychain["kishikawakatsumi"]

let token = keychain[string: "kishikawakatsumi"]

for NSData

let secretData = keychain[data: "secret"]

get methods

as String

let token = try? keychain.get("kishikawakatsumi")

let token = try? keychain.getString("kishikawakatsumi")

as NSData

let data = try? keychain.getData("kishikawakatsumi")

:key: Removing an item

subscripting

keychain["kishikawakatsumi"] = nil

remove method

do {
    try keychain.remove("kishikawakatsumi")
} catch let error {
    print("error: \(error)")
}

:key: Set Label and Comment

let keychain = Keychain(server: "https://github.com", protocolType: .https)
do {
    try keychain
        .label("github.com (kishikawakatsumi)")
        .comment("github access token")
        .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
} catch let error {
    print("error: \(error)")
}

:key: Obtaining Other Attributes

PersistentRef

let keychain = Keychain()
let persistentRef = keychain[attributes: "kishikawakatsumi"]?.persistentRef
...

Creation Date

let keychain = Keychain()
let creationDate = keychain[attributes: "kishikawakatsumi"]?.creationDate
...

All Attributes

let keychain = Keychain()
do {
    let attributes = try keychain.get("kishikawakatsumi") { $0 }
    print(attributes?.comment)
    print(attributes?.label)
    print(attributes?.creator)
    ...
} catch let error {
    print("error: \(error)")
}

subscripting

let keychain = Keychain()
if let attributes = keychain[attributes: "kishikawakatsumi"] {
    print(attributes.comment)
    print(attributes.label)
    print(attributes.creator)
}

:key: Configuration (Accessibility, Sharing, iCloud Sync)

Provides fluent interfaces

let keychain = Keychain(service: "com.example.github-token")
    .label("github.com (kishikawakatsumi)")
    .synchronizable(true)
    .accessibility(.afterFirstUnlock)

Accessibility

Default accessibility matches background application (=kSecAttrAccessibleAfterFirstUnlock)

let keychain = Keychain(service: "com.example.github-token")

For background application

Creating instance

let keychain = Keychain(service: "com.example.github-token")
    .accessibility(.afterFirstUnlock)

keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

One-shot

let keychain = Keychain(service: "com.example.github-token")

do {
    try keychain
        .accessibility(.afterFirstUnlock)
        .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
} catch let error {
    print("error: \(error)")
}

For foreground application

Creating instance

let keychain = Keychain(service: "com.example.github-token")
    .accessibility(.whenUnlocked)

keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

One-shot

let keychain = Keychain(service: "com.example.github-token")

do {
    try keychain
        .accessibility(.whenUnlocked)
        .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
} catch let error {
    print("error: \(error)")
}

:couple: Sharing Keychain items

let keychain = Keychain(service: "com.example.github-token", accessGroup: "12ABCD3E4F.shared")

:arrows_counterclockwise: Synchronizing Keychain items with iCloud

Creating instance

let keychain = Keychain(service: "com.example.github-token")
    .synchronizable(true)

keychain["kishikawakatsumi"] = "01234567-89ab-cdef-0123-456789abcdef"

One-shot

let keychain = Keychain(service: "com.example.github-token")

do {
    try keychain
        .synchronizable(true)
        .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
} catch let error {
    print("error: \(error)")
}

:cyclone: Touch ID (Face ID) integration

Any Operation that require authentication must be run in the background thread.
If you run in the main thread, UI thread will lock for the system to try to display the authentication dialog.

To use Face ID, add NSFaceIDUsageDescription key to your Info.plist

:closed_lock_with_key: Adding a Touch ID (Face ID) protected item

If you want to store the Touch ID protected Keychain item, specify accessibility and authenticationPolicy attributes.

let keychain = Keychain(service: "com.example.github-token")

DispatchQueue.global().async {
    do {
        // Should be the secret invalidated when passcode is removed? If not then use `.WhenUnlocked`
        try keychain
            .accessibility(.whenPasscodeSetThisDeviceOnly, authenticationPolicy: [.biometryAny])
            .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
    } catch let error {
        // Error handling if needed...
    }
}

:closed_lock_with_key: Updating a Touch ID (Face ID) protected item

The same way as when adding.

Do not run in the main thread if there is a possibility that the item you are trying to add already exists, and protected. Because updating protected items requires authentication.

Additionally, you want to show custom authentication prompt message when updating, specify an authenticationPrompt attribute. If the item not protected, the authenticationPrompt parameter just be ignored.

let keychain = Keychain(service: "com.example.github-token")

DispatchQueue.global().async {
    do {
        // Should be the secret invalidated when passcode is removed? If not then use `.WhenUnlocked`
        try keychain
            .accessibility(.whenPasscodeSetThisDeviceOnly, authenticationPolicy: [.biometryAny])
            .authenticationPrompt("Authenticate to update your access token")
            .set("01234567-89ab-cdef-0123-456789abcdef", key: "kishikawakatsumi")
    } catch let error {
        // Error handling if needed...
    }
}

:closed_lock_with_key: Obtaining a Touch ID (Face ID) protected item

The same way as when you get a normal item. It will be displayed automatically Touch ID or passcode authentication If the item you try to get is protected.
If you want to show custom authentication prompt message, specify an authenticationPrompt attribute. If the item not protected, the authenticationPrompt parameter just be ignored.

let keychain = Keychain(service: "com.example.github-token")

DispatchQueue.global().async {
    do {
        let password = try keychain
            .authenticationPrompt("Authenticate to login to server")
            .get("kishikawakatsumi")

        print("password: \(password)")
    } catch let error {
        // Error handling if needed...
    }
}

:closed_lock_with_key: Removing a Touch ID (Face ID) protected item

The same way as when you remove a normal item. There is no way to show Touch ID or passcode authentication when removing Keychain items.

let keychain = Keychain(service: "com.example.github-token")

do {
    try keychain.remove("kishikawakatsumi")
} catch let error {
    // Error handling if needed...
}

:key: Shared Web Credentials

Shared web credentials is a programming interface that enables native iOS apps to share credentials with their website counterparts. For example, a user may log in to a website in Safari, entering a user name and password, and save those credentials using the iCloud Keychain. Later, the user may run a native app from the same developer, and instead of the app requiring the user to reenter a user name and password, shared web credentials gives it access to the credentials that were entered earlier in Safari. The user can also create new accounts, update passwords, or delete her account from within the app. These changes are then saved and used by Safari.
https://developer.apple.com/library/ios/documentation/Security/Reference/SharedWebCredentialsRef/

let keychain = Keychain(server: "https://www.kishikawakatsumi.com", protocolType: .HTTPS)

let username = "[email protected]"

// First, check the credential in the app's Keychain
if let password = try? keychain.get(username) {
    // If found password in the Keychain,
    // then log into the server
} else {
    // If not found password in the Keychain,
    // try to read from Shared Web Credentials
    keychain.getSharedPassword(username) { (password, error) -> () in
        if password != nil {
            // If found password in the Shared Web Credentials,
            // then log into the server
            // and save the password to the Keychain

            keychain[username] = password
        } else {
            // If not found password either in the Keychain also Shared Web Credentials,
            // prompt for username and password

            // Log into server

            // If the login is successful,
            // save the credentials to both the Keychain and the Shared Web Credentials.

            keychain[username] = inputPassword
            keychain.setSharedPassword(inputPassword, account: username)
        }
    }
}

Request all associated domain's credentials

Keychain.requestSharedWebCredential { (credentials, error) -> () in

}

Generate strong random password

Generate strong random password that is in the same format used by Safari autofill (xxx-xxx-xxx-xxx).

let password = Keychain.generatePassword() // => Nhu-GKm-s3n-pMx

How to set up Shared Web Credentials

1. Add a com.apple.developer.associated-domains entitlement to your app. This entitlement must include all the domains with which you want to share credentials.

2. Add an apple-app-site-association file to your website. This file must include application identifiers for all the apps with which the site wants to share credentials, and it must be properly signed.

3. When the app is installed, the system downloads and verifies the site association file for each of its associated domains. If the verification is successful, the app is associated with the domain.

More details:
https://developer.apple.com/library/ios/documentation/Security/Reference/SharedWebCredentialsRef/

:mag: Debugging

Display all stored items if print keychain object

let keychain = Keychain(server: "https://github.com", protocolType: .https)
print("\(keychain)")

=>
[
  [authenticationType: default, key: kishikawakatsumi, server: github.com, class: internetPassword, protocol: https]
  [authenticationType: default, key: hirohamada, server: github.com, class: internetPassword, protocol: https]
  [authenticationType: default, key: honeylemon, server: github.com, class: internetPassword, protocol: https]
]

Obtaining all stored keys

let keychain = Keychain(server: "https://github.com", protocolType: .https)

let keys = keychain.allKeys()
for key in keys {
  print("key: \(key)")
}

=>
key: kishikawakatsumi
key: hirohamada
key: honeylemon

Obtaining all stored items

let keychain = Keychain(server: "https://github.com", protocolType: .https)

let items = keychain.allItems()
for item in items {
  print("item: \(item)")
}

=>
item: [authenticationType: Default, key: kishikawakatsumi, server: github.com, class: InternetPassword, protocol: https]
item: [authenticationType: Default, key: hirohamada, server: github.com, class: InternetPassword, protocol: https]
item: [authenticationType: Default, key: honeylemon, server: github.com, class: InternetPassword, protocol: https]

Keychain sharing capability

If you encounter the error below, you need to add an Keychain.entitlements.

OSStatus error:[-34018] Internal error when a required entitlement isn't present, client has neither application-identifier nor keychain-access-groups entitlements.

Requirements

Installation

CocoaPods

KeychainAccess is available through CocoaPods. To install it, simply add the following lines to your Podfile:

use_frameworks!
pod 'KeychainAccess'

Carthage

KeychainAccess is available through Carthage. To install it, simply add the following line to your Cartfile:

github "kishikawakatsumi/KeychainAccess"

Swift Package Manager

KeychainAccess is also available through Swift Package Manager.

Xcode

Select File > Add Packages... > Add Package Dependency...,

CLI

First, create Package.swift that its package declaration includes:

// swift-tools-version:5.0
import PackageDescription

let package = Package(
    name: "MyLibrary",
    products: [
        .library(name: "MyLibrary", targets: ["MyLibrary"]),
    ],
    dependencies: [
        .package(url: "https://github.com/kishikawakatsumi/KeychainAccess.git", from: "3.0.0"),
    ],
    targets: [
        .target(name: "MyLibrary", dependencies: ["KeychainAccess"]),
    ]
)

Then, type

$ swift build

To manually add to your project

1. Add Lib/KeychainAccess.xcodeproj to your project
2. Link KeychainAccess.framework with your target
3. Add Copy Files Build Phase to include the framework to your application bundle

See iOS Example Project as reference.

Author

kishikawa katsumi, [email protected]

License

KeychainAccess is available under the MIT license. See the LICENSE file for more info.