FIPS 140-2 validation and FileVault 2

One question I’ve seen which has caused confusion for folks who deal with security regulations is this: Is FileVault 2 FIPS 140-2 compliant?

The answer is: Yes, depending on the version of OS X

The cryptography used by FileVault 2 on the following versions of OS X has gone through the FIPS validation process and has been validated as being FIPS 140-2 Compliant:

• OS X 10.8.x
• OS X 10.9.x
• OS X 10.10.x

The CoreCrypto cryptographic modules used by OS X 10.11 are currently in the process of becoming FIPS 140-2 validated. The reason FileVault 2 in El Capitan is not automatically FIPS 140-2 compliant has to do with OS X’s CoreCrypto cryptography foundation and how the FIPS 140-2 validation process works.

FIPS validation

The FIPS validation process tests a specific cryptographic module used inside a system to protect information. It also applies only to a cryptographic module used in a shipping product; the cryptographic module in question can’t be a prototype or in beta. 

Another important thing to know is that the testing is very specific and applies only to the cryptographic module submitted for review. If the vendor changes anything in the cryptographic module, it loses its FIPS validation and has to be resubmitted for laboratory testing and government review.

There are three major phases in the process:

Phase 1: Design and Documentation

In order to prepare for the FIPS validation process, the cryptographic module in question has to be designed to pass the various tests involved and also be properly documented. This is the part of the process which the vendor has the most control over.

Phase 2: Laboratory Testing

Once the cryptographic module has been designed, documented and shipped, it is submitted to a third-party accredited Cryptographic and Security Testing (CST) laboratory to test the module(s) in question against FIPS 140-2’s qualitative levels of security. This testing can take an indeterminate amount of time, depending on how well the cryptographic module is designed and documented.

Best case: A cryptographic module that properly meets the requirements and with all required documentation written correctly can complete its laboratory testing in two to three months.

Phase 3: Government Review

After the lab has tested the cryptographic module, a report on the testing is submitted to the Cryptographic Module Validation Program (CMVP) for review. CMVP is a joint US-Canadian program that reviews all the test reports, with the CMVP Validation Authorities being the National Institute of Standards and Technology (NIST) for the US Government and the Communications Security Establishment (CSE) for the Government of Canada. This review can also take an indeterminate amount of time, depending on how many test reports need review, and can range from two months to eight months.

Apple and CoreCrypto

Apple’s CoreCrypto library is used by various components in OS X to provide low level cryptographic primitive support. This is the cryptographic library which is submitted by Apple to the FIPS 140-2 validation process.

With every version of iOS and OS X, Apple has made changes to CoreCrypto. As part of making those changes, Apple has had to resubmit CoreCrypto to laboratory testing and government review as part of the FIPS 140-2 validation process.

Apple’s stated intention is to continue FIPS 140-2 validation for OS X’s CoreCrypto cryptography foundation, which would also cover FileVault 2 on future versions of OS X, but the validation process itself can only be begun once that future OS has been released. Meanwhile, as noted above, the testing and governmental review process will take months to complete.

The good news is that it’s possible to at least see where Apple is in the process. NIST has a website where the current list of modules in the process can be viewed via a PDF which is updated weekly. To check for Apple’s progress, search the PDF for entries where Apple Inc. is listed as the vendor.

For more information on this subject, Apple has KBase articles available via the links below:

Product security, validations, and guidance for iOS

Product security, validations, and guidance for OS X

Apple’s existing FIPS validations are also available for reference via the link below:

http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/1401vend.htm