Built-in authenticated encryption implementation in iOS?

Question

Do any of the built-in iOS security libraries contain an implementation of authenticated encryption? If so, which ones? I have been unable to locate any reference of this in the Apple documentation.

I know OpenSSL contains one, but OpenSSL isn't built in and has some other issues for our system.

Answer 1

No, it does not. There was some discussion of this issue on sci.crypt back in 2012 and I do not believe that the situation has changed. My understanding is that there are some patent issues regarding authenticated encryption. It's almost certainly easier for Apple to avoid them by requiring encryption and authentication as two steps. Of course, you can always implement it yourself; it's not that hard and there are source code implementations available.

For those who don't know what the big deal is about Authenticated Encryption, Phillip Rogaway gave a nice presentation on it at Stanford in January 2013. The primary error in the presentation is on slide #39, where it states that there is an "Open-Source" Software Implementation of OCB, but the license is only for Non-Military users, so it is not technically "open source"