Swift Obfuscator

Obfuscator.swift

class Obfuscator {
    
    // MARK: - Variables
    
    /// The salt used to obfuscate and reveal the string.
    private var salt: String
    
    // MARK: - Initialization
    
    init() {
        self.salt = "\(String(describing: SceneDelegate.self))\(String(describing: NSString.self))"
    }
    
    init(with salt: String) {
        self.salt = salt
    }
    
    
    // MARK: - Instance Methods
    
    /**
     This method obfuscates the string passed in using the salt
     that was used when the Obfuscator was initialized.
     
     - parameter string: the string to obfuscate
     
     - returns: the obfuscated string in a byte array
     */
    func bytesByObfuscatingString(string: String) -> [UInt8] {
        let text = [UInt8](string.utf8)
        let cipher = [UInt8](self.salt.utf8)
        let length = cipher.count
        
        var encrypted = [UInt8]()
        
        for t in text.enumerated() {
            encrypted.append(t.element ^ cipher[t.offset % length])
        }
        
        return encrypted
    }
    
    /**
     This method reveals the original string from the obfuscated
     byte array passed in. The salt must be the same as the one
     used to encrypt it in the first place.
     
     - parameter key: the byte array to reveal
     
     - returns: the original string
     */
    func reveal(key: [UInt8]) -> String {
        let cipher = [UInt8](self.salt.utf8)
        let length = cipher.count
        
        var decrypted = [UInt8]()
        
        for k in key.enumerated() {
            decrypted.append(k.element ^ cipher[k.offset % length])
        }
        
        return String(bytes: decrypted, encoding: .utf8)!
    }
}


// EXAMPLE: 

final class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        let obfuscator = Obfuscator()
        print(obfuscator.bytesByObfuscatingString(string: "your_secret_string_here"))
        print(obfuscator.reveal(key: ObfuscatedConstants.obfuscatedString))
    }
}

enum ObfuscatedConstants {
    static let obfuscatedString: [UInt8] = [34, 17, 93, 37, 21, 28, 72, 23, 20, 22, 72, 127, 98, 123, 87, 94, 92, 83, 76, 113]
}