Keychain for secure storage in iOS Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a dictionary for Keychain query with the service name.

iOS Swift

let query: [String: Any] = [kSecClass as String: kSecClassGenericPassword, kSecAttrService as String: [1]]

Drag options to blanks, or click blank then click option'

A"com.example.myapp"

BkSecClassGenericPassword

C"password"

DkSecAttrAccount

Attempts:

3 left

💡 Hint

Common Mistakes

Using kSecClassGenericPassword instead of a string for service.

Using kSecAttrAccount where service is expected.

The service name must be a string identifying your app or service, so "com.example.myapp" is correct.

2fill in blank

medium

Complete the code to convert a password string to Data for Keychain storage.

iOS Swift

let passwordData = password.[1]!

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Adata()

BdataValue()

Cutf8Data()

Ddata(using: .utf8)

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-existent method like utf8Data() or dataValue().

Forgetting to unwrap the optional result.

The correct method to convert a string to Data with UTF-8 encoding is data(using: .utf8).

3fill in blank

hard

Fix the error in the Keychain add query by completing the code to set the password data.

iOS Swift

query[kSecValueData as String] = [1]

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ApasswordData

Bpassword

CpasswordString

Dpassword.data

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning a String instead of Data to kSecValueData.

Using a variable name that does not exist.

The value for kSecValueData must be Data type, so passwordData is correct.

4fill in blank

hard

Fill both blanks to complete the code that retrieves password data from Keychain and converts it to String.

iOS Swift

if let data = result as? Data, let password = String([1]: data, [2]: .utf8) {
    print(password)
}

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Ainit

Bdata

Cencoding

Ddecode

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'data' instead of 'init' for String initialization.

Using 'decode' instead of 'encoding' parameter.

To convert Data to String, use String.init(data:encoding:).

5fill in blank

hard

Fill all three blanks to complete the code that updates an existing Keychain item with new password data.

iOS Swift

let updateQuery: [String: Any] = [kSecClass as String: [1], kSecAttrService as String: service]
let attributesToUpdate: [String: Any] = [kSecValueData as String: [2]]
let status = SecItemUpdate(updateQuery as CFDictionary, [3] as CFDictionary)

Drag options to blanks, or click blank then click option'

AkSecClassGenericPassword

BpasswordData

CattributesToUpdate

Dservice

Attempts:

3 left

💡 Hint

Common Mistakes

Passing service instead of attributesToUpdate to SecItemUpdate.

Using wrong constants for kSecClass.

To update Keychain, specify the class, new data, and pass attributesToUpdate to SecItemUpdate.