PBKDF2-HMAC-SHA256 Objective-C implementation

Can someone point me to an implementation of PBKDF2 using 开发者_Go百科HMAC-SHA256 to generate a key, in Objective-C. This is part of the key generation process that I will later use for AES-CBC-Pad encryption.

Thanks in advance

You can just simply borrow C implementation from OpenSSL or any other library.