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Authentication

Authentication is the process of verifying the identity of a user or service. Authentication is normally done only as a step in authorization. Authentication answers the question “Is this entity who it claims to be?” before authorization asks “Does this entity have permission to perform this operation?” Therefore, Mac OS X has no separate authentication API. Some applications and operating system components carry out their own authentication; for example, see “Movie Toolbox Access Keys.” Authorization Services handles authentication for you when necessary (see “Authorization Services”). If you are using digital certificates for authentication—for example, when you need to authenticate a web server— use the functions in Certificate, Key, and Trust Services. See “Certificate, Key, and Trust Services” for a description of that API. To exchange certificates over a secure connection, use the Secure Transport API described in “Secure Transport” (or one of the high-level APIs that call Secure Transport—see “CFNetwork” or “URL Loading System”). To authenticate with a directory server, use the Open Directory API. See Open Directory Programming Guide in Networking Documentation for details.

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