Login Process - Determining if user has already logged in

[BenCrosthwaite]

Hello Everyone,

I'm building an application, which requires the user to log in. Once the user has logged in, they will not need to log in again if the close and re-open the application.

If the log in is successful I store the password in the keychain, using the code from this blog.

This is where I am stuck. If the user has closed the application and then reopened it, the application will start up again. From this point I need to determine if their login credentials are valid, username and password, if so there is no need to display the login screen.

Using the Keychain code from above, the method to return the password requires the username and service name

+ (NSString *) getPasswordForUsername: (NSString *) username andServiceName: (NSString *) serviceName error: (NSError **) error

The service name is not an issue but the username is presenting me with a problem.

What is the best way to store the username in order to check if the keychain value exists?

Regards,
-Ben

[Speed]

Why don't you store the username in the keychain as well? I believe that the keychain works in key-value pairs, which would allow you to store the username under the key "username" and the password under the key "password" (or something similar). This is what I do in my keychain-utilizing application, that has this same functionality.

[BenCrosthwaite]

Hi Speed,

Thanks for the promt response. I think i may have been confused by the use of language on the SFHFKeychainUtils add method.

The add method is:

+ (BOOL) storeUsername: (NSString *) username andPassword: (NSString *) password forServiceName: (NSString *) serviceName updateExisting: (BOOL) updateExisting error: (NSError **) error;

I assumed that this meant i was saving both the username and the password the user inputs in the log in form.

However, im starting to think this is the key value system. So storeUsername: (NSString *) username: is the key and andPassword: (NSString *) password is the value.

Is this correct?

Regards,
-Ben

[aaronov]

From memory I store the username in the user defaults, if it is present and a password exists in the keychain then I attempt login with those details - if login fails I then show the login screen.

[baja_yu]

Originally Posted by aaronov

From memory I store the username in the user defaults, if it is present and a password exists in the keychain then I attempt login with those details - if login fails I then show the login screen.

User defaults are an extremely insecure way of storing any sensitive data.

[Sunny46]

Originally Posted by baja_yu

User defaults are an extremely insecure way of storing any sensitive data.

I am having problem using SFHFKeychainUtils.h for ios 5 ,can anyone help me finding the version for ios5?