The same libraries that secure iOS and OS X are available to third‑party developers to help them build advanced security features.
Security Framework provides interfaces for managing certificates, public and private keys, and trust policies. It supports the generation of cryptographically secure pseudorandom numbers. It also supports the storage of certificates and cryptographic keys in the keychain, which is a secure repository for sensitive user data.
The Common Crypto library provides additional support for operations like symmetric encryption, hash-based message authentication codes, and digests.
Both Security Framework and Common Crypto rely on the corecrypto library to provide implementations of low level cryptographic primitives. This is also the library submitted for validation of compliance with U.S. Federal Information Processing Standards (FIPS) 140-2 Level 1. Although corecrypto does not directly provide programming interfaces for developers and should not be used by iOS or OS X apps, the source code is available to allow for verification of its security characteristics and correct functioning.