Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
262 views
in Technique[技术] by (71.8m points)

ios - Programmatically Checking if a Passcode Lock is Set

Since my app would be dealing with sensitive data of the user, I would like to know if there is a way I can check from my app whether there is a Passcode Lock set in iOS.

The reason I need to check this is because say if the user has in the app some information and then keeps it on the table and goes out for a couple of minutes. The iPad/iPhone by default, goes to standby mode. If a passcode lock had been set, only when the correct passcode is entered, would anyone be able to use the ipad. This would provide an additional security measure to prevent any passerby to view the sensitive data from the app.

So basically, I would like my app to check whether the passcode lock is set and if not prompt the user to do it.

Is this possible?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

With iOS 8, there is now a way to check that the user has a passcode set. This code will crash on iOS 7.

Objective-C:

-(BOOL) deviceHasPasscode {
    NSData* secret = [@"Device has passcode set?" dataUsingEncoding:NSUTF8StringEncoding];
    NSDictionary *attributes = @{ (__bridge id)kSecClass: (__bridge id)kSecClassGenericPassword, (__bridge id)kSecAttrService: @"LocalDeviceServices",  (__bridge id)kSecAttrAccount: @"NoAccount", (__bridge id)kSecValueData: secret, (__bridge id)kSecAttrAccessible: (__bridge id)kSecAttrAccessibleWhenPasscodeSetThisDeviceOnly };

    OSStatus status = SecItemAdd((__bridge CFDictionaryRef)attributes, NULL);
    if (status == errSecSuccess) { // item added okay, passcode has been set            
        SecItemDelete((__bridge CFDictionaryRef)attributes);

        return true;
    }

    return false;
}

Swift:

func deviceHasPasscode() -> Bool {
    let secret = "Device has passcode set?".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)
    let attributes = [kSecClass as String:kSecClassGenericPassword, kSecAttrService as String:"LocalDeviceServices", kSecAttrAccount as String:"NoAccount", kSecValueData as String:secret!, kSecAttrAccessible as String:kSecAttrAccessibleWhenPasscodeSetThisDeviceOnly]

    let status = SecItemAdd(attributes, nil)
    if status == 0 {
        SecItemDelete(attributes)
        return true
    }

    return false
}

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...