Wednesday, November 19, 2014

ICMC: Comparing ISO/IEC 19790 and FIPS PUB 140-2

William Tung, Leidos, Laboratory Manager

ISO/IEC 19790:2012 is the planned replacement for FIPS 140-2, but there's been no official announcement or timeframe, yet. This means no labs are accredited to perform these validations.

But... it's coming.

Some of this will be a rehash of our earlier sessions, but with more deep diving per section.

Degraded Operation

This mode can only be used after exiting an error state and must be able to provide information about this state.  Whatever mechanism or function is causing the failure shall be isolated.  While in the degraded mode, all conditional algorithm self-tests shall be performed prior to the first operational use of the algorithm and before degradation can be removed, all tests must pass

Cryptographic Module Interface

The cryptographic module interface is a fifth logical interface that cannot be used whenever you're in an error state.

Roles, Services and Authentication

The user role is optional, there is a minimum requirement of a crypto-officer role.  The minimal service requires showing the module's versioning info that matches the certificate on record.

There is also a new requirement for self-initiated cryptographic output capability.

Authentication strength requirements must be met by the module's implementation, not through policy controls or security rules.  For example, password size restrictions. ISO 19790 does not yet define what exactly those strength requirements are.  Level 4 modules will have to implement multi-factor authentication.

Software/Firmware Security

This section of the document applies only to software/firmware or hardware modules. Level 2 modules must implement an approved digital signature or keyed MAC for integrity test, Levels 3 & 4 have higher requirements.

Operational Environment

Software modules no longer need to operate in Common Criteria (CC) evlauted OS or "trusted operating system in order to meet Level 2 requirements.  There are specific OS requirements still required to meet Levels 2-4 (that will look similar to what used to be covered by CC).

Physical Security

Explicitly allows translucent enclosers/cases, in addition to FIPS 140-2 allowed opaque enclosures/cases, within the visible spectrum.  Level 3 modules must either implement environmental failure protection (EFP) or undergo environmental failure testing (EFT).  Level 4 MUST implement EFP.

Non-Invasive Security

This section currently doesn't specify requirements, but they will come. Hardware and firmware must comply and it will be optional for software  For levels 1-2, module must protect against these attacks. Level 3-4 will have to prove protection.

Sensitive Security Parameter (SSP) Management

SSPs consists of Critical Security Parameters (CPSs) and Public Security Parameters (PSPs). For Level 2 modules and up, procedural zeroization is not allowed.

Self Tests

There are two categories of self-test: Pre-operational and conditional.  Pre-operational includes things like integrity test and critical functions test. Conditional covers the other standard conditional tests plus the other items covered in the old POST guidance.

All self-tests need to be run regardless of if module is operating in approved or non-approved mode.  Level 3 & 4 modules must include an error log that is acceisble by an authorized operator of the module.  Integrity test needs to be run over all software/firmware components of module.  At a minimum, vendor must implement one cryptographic algorithm self-test as a pre-operational test.
[Clarification from Randall Easter on this topic: If the module is installed and configured as a FIPS 140 module, then it must do all of these tests/checks.  If it was installed and configured otherwise, it's not required. This is not different than what is currently required by FIPS 140-2.]

FIPS CRNGT is not currently defined in ISO.

ISO 1970 requires Level 3 & 4 modules to do automatic pre-operational self-tests at a predefined (by vendor) interval.

Life-Cycle Assurance

This seems to be more of a documentation and QE section. Covers vendor testing and finite state model. The states required are: General Initialization State, User State, and Approved State.  Changing to crypto-officer from any other role is prohibited.

Testing Requirements for Cryptographic Modules

The next part of the talk came from Zhiqiang (Richard) Wang, Leidos, Senior Security Engineer.

The testing requirements were derived from the FIPS 140-2 derived testing requirements. This covers self-tests, live cycle assurance and mitigation of other attacks.

ISO/IEC 24759:2014 specified shte methods to be used by testing laboratories to test whether the cryptographic module conforms to the requiremetns speified in ISO/IEC 19790:2012.  This was developed to provide a high degree of objectivity during the testing proess and to ensure consistency across the testing laboratories.  It clearly specifies what the vendor needs to provide to the laboratory.

Richard spent time walking through section by section going through many of the same requirements discussed early, but with a twist on how it would be tested or why.

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