ios 从钥匙串保存和加载 | 迅速

Save and Load from KeyChain | Swift

提问by Sazzad Hissain Khan

How to simply store a String in Keychain and load when needed. There are several SO solution which mostly refers to Git repo. But I need the smallest and the simplest solution on latest Swift. Certainly, I don't want to add git framework for simply storing a password in my project.

如何简单地将字符串存储在钥匙串中并在需要时加载。有几种 SO 解决方案，主要是指 Git 存储库。但我需要最新 Swift 上最小和最简单的解决方案。当然，我不想添加 git 框架来简单地在我的项目中存储密码。

There are similar solution Save and retrieve value via KeyChain, which did not work for me. Tired with compiler errors.

有类似的解决方案通过 KeyChain 保存和检索值，这对我不起作用。厌倦了编译器错误。

回答by Sazzad Hissain Khan

Simplest Source

最简单的来源

import Foundation
import Security

// Constant Identifiers
let userAccount = "AuthenticatedUser"
let accessGroup = "SecuritySerivice"


/** 
 *  User defined keys for new entry
 *  Note: add new keys for new secure item and use them in load and save methods
 */

let passwordKey = "KeyForPassword"

// Arguments for the keychain queries
let kSecClassValue = NSString(format: kSecClass)
let kSecAttrAccountValue = NSString(format: kSecAttrAccount)
let kSecValueDataValue = NSString(format: kSecValueData)
let kSecClassGenericPasswordValue = NSString(format: kSecClassGenericPassword)
let kSecAttrServiceValue = NSString(format: kSecAttrService)
let kSecMatchLimitValue = NSString(format: kSecMatchLimit)
let kSecReturnDataValue = NSString(format: kSecReturnData)
let kSecMatchLimitOneValue = NSString(format: kSecMatchLimitOne)

public class KeychainService: NSObject {

    /**
     * Exposed methods to perform save and load queries.
     */

    public class func savePassword(token: NSString) {
        self.save(passwordKey, data: token)
    }

    public class func loadPassword() -> NSString? {
        return self.load(passwordKey)
    }

    /**
     * Internal methods for querying the keychain.
     */

    private class func save(service: NSString, data: NSString) {
        let dataFromString: NSData = data.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!

        // Instantiate a new default keychain query
        let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, userAccount, dataFromString], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue, kSecValueDataValue])

        // Delete any existing items
        SecItemDelete(keychainQuery as CFDictionaryRef)

        // Add the new keychain item
        SecItemAdd(keychainQuery as CFDictionaryRef, nil)
    }

    private class func load(service: NSString) -> NSString? {
        // Instantiate a new default keychain query
        // Tell the query to return a result
        // Limit our results to one item
        let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, userAccount, kCFBooleanTrue, kSecMatchLimitOneValue], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue, kSecReturnDataValue, kSecMatchLimitValue])

        var dataTypeRef :AnyObject?

        // Search for the keychain items
        let status: OSStatus = SecItemCopyMatching(keychainQuery, &dataTypeRef)
        var contentsOfKeychain: NSString? = nil

        if status == errSecSuccess {
            if let retrievedData = dataTypeRef as? NSData {
                contentsOfKeychain = NSString(data: retrievedData, encoding: NSUTF8StringEncoding)
            }
        } else {
            print("Nothing was retrieved from the keychain. Status code \(status)")
        }

        return contentsOfKeychain
    }
}

Example of Calling

调用示例

KeychainService.savePassword("Pa55worD")
let password = KeychainService.loadPassword() // password = "Pa55worD"

SWIFT 4: VERSION WITH UPDATE AND REMOVE PASSWORD

SWIFT 4：带有更新和删除密码的版本

import Cocoa
import Security

// see https://stackoverflow.com/a/37539998/1694526
// Arguments for the keychain queries
let kSecClassValue = NSString(format: kSecClass)
let kSecAttrAccountValue = NSString(format: kSecAttrAccount)
let kSecValueDataValue = NSString(format: kSecValueData)
let kSecClassGenericPasswordValue = NSString(format: kSecClassGenericPassword)
let kSecAttrServiceValue = NSString(format: kSecAttrService)
let kSecMatchLimitValue = NSString(format: kSecMatchLimit)
let kSecReturnDataValue = NSString(format: kSecReturnData)
let kSecMatchLimitOneValue = NSString(format: kSecMatchLimitOne)

public class KeychainService: NSObject {

    class func updatePassword(service: String, account:String, data: String) {
        if let dataFromString: Data = data.data(using: String.Encoding.utf8, allowLossyConversion: false) {

            // Instantiate a new default keychain query
            let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, account], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue])

            let status = SecItemUpdate(keychainQuery as CFDictionary, [kSecValueDataValue:dataFromString] as CFDictionary)

            if (status != errSecSuccess) {
                if let err = SecCopyErrorMessageString(status, nil) {
                    print("Read failed: \(err)")
                }
            }
        }
    }


    class func removePassword(service: String, account:String) {

        // Instantiate a new default keychain query
        let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, account, kCFBooleanTrue], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue, kSecReturnDataValue])

        // Delete any existing items
        let status = SecItemDelete(keychainQuery as CFDictionary)
        if (status != errSecSuccess) {
            if let err = SecCopyErrorMessageString(status, nil) {
                print("Remove failed: \(err)")
            }
        }

    }


    class func savePassword(service: String, account:String, data: String) {
        if let dataFromString = data.data(using: String.Encoding.utf8, allowLossyConversion: false) {

            // Instantiate a new default keychain query
            let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, account, dataFromString], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue, kSecValueDataValue])

            // Add the new keychain item
            let status = SecItemAdd(keychainQuery as CFDictionary, nil)

            if (status != errSecSuccess) {    // Always check the status
                if let err = SecCopyErrorMessageString(status, nil) {
                    print("Write failed: \(err)")
                }
            }
        }
    }

    class func loadPassword(service: String, account:String) -> String? {
        // Instantiate a new default keychain query
        // Tell the query to return a result
        // Limit our results to one item
        let keychainQuery: NSMutableDictionary = NSMutableDictionary(objects: [kSecClassGenericPasswordValue, service, account, kCFBooleanTrue, kSecMatchLimitOneValue], forKeys: [kSecClassValue, kSecAttrServiceValue, kSecAttrAccountValue, kSecReturnDataValue, kSecMatchLimitValue])

        var dataTypeRef :AnyObject?

        // Search for the keychain items
        let status: OSStatus = SecItemCopyMatching(keychainQuery, &dataTypeRef)
        var contentsOfKeychain: String?

        if status == errSecSuccess {
            if let retrievedData = dataTypeRef as? Data {
                contentsOfKeychain = String(data: retrievedData, encoding: String.Encoding.utf8)
            }
        } else {
            print("Nothing was retrieved from the keychain. Status code \(status)")
        }

        return contentsOfKeychain
    }

}

You need to imagine the following wired up to a text input field and a label, then having four buttons wired up, one for each of the methods.

您需要想象以下内容连接到一个文本输入字段和一个标签，然后连接了四个按钮，每个方法一个。

class ViewController: NSViewController {
    @IBOutlet weak var enterPassword: NSTextField!
    @IBOutlet weak var retrievedPassword: NSTextField!

    let service = "myService"
    let account = "myAccount"

    // will only work after
    @IBAction func updatePassword(_ sender: Any) {
        KeychainService.updatePassword(service: service, account: account, data: enterPassword.stringValue)
    }

    @IBAction func removePassword(_ sender: Any) {
        KeychainService.removePassword(service: service, account: account)
    }

    @IBAction func passwordSet(_ sender: Any) {
        let password = enterPassword.stringValue
        KeychainService.savePassword(service: service, account: account, data: password)
    }

    @IBAction func passwordGet(_ sender: Any) {
        if let str = KeychainService.loadPassword(service: service, account: account) {
            retrievedPassword.stringValue = str
        }
        else {retrievedPassword.stringValue = "Password does not exist" }
    }
}

Swift 5

斯威夫特 5

Kosuke's versionfor swift 5

Kosuke 的swift 5版本

import Security

class KeyChain {

    class func save(key: String, data: Data) -> OSStatus {
        let query = [
            kSecClass as String       : kSecClassGenericPassword as String,
            kSecAttrAccount as String : key,
            kSecValueData as String   : data ] as [String : Any]

        SecItemDelete(query as CFDictionary)

        return SecItemAdd(query as CFDictionary, nil)
    }

    class func load(key: String) -> Data? {
        let query = [
            kSecClass as String       : kSecClassGenericPassword,
            kSecAttrAccount as String : key,
            kSecReturnData as String  : kCFBooleanTrue!,
            kSecMatchLimit as String  : kSecMatchLimitOne ] as [String : Any]

        var dataTypeRef: AnyObject? = nil

        let status: OSStatus = SecItemCopyMatching(query as CFDictionary, &dataTypeRef)

        if status == noErr {
            return dataTypeRef as! Data?
        } else {
            return nil
        }
    }

    class func createUniqueID() -> String {
        let uuid: CFUUID = CFUUIDCreate(nil)
        let cfStr: CFString = CFUUIDCreateString(nil, uuid)

        let swiftString: String = cfStr as String
        return swiftString
    }
}

extension Data {

    init<T>(from value: T) {
        var value = value
        self.init(buffer: UnsafeBufferPointer(start: &value, count: 1))
    }

    func to<T>(type: T.Type) -> T {
        return self.withUnsafeBytes { 
let int: Int = 555
let data = Data(from: int)
let status = KeyChain.save(key: "MyNumber", data: data)
print("status: ", status)

if let receivedData = KeyChain.load(key: "MyNumber") {
    let result = receivedData.to(type: Int.self)
    print("result: ", result)
}
.load(as: T.self) }
    }
}

Example usage:

用法示例：

##代码##