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Cisco FIPS Object Module
FIPS 140-2 Non-Proprietary Security Policy
Cisco Systems, Inc.
DOCUMENT VERSION: 3.0
December 15, 2015
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Table of Contents
1 INTRODUCTION.................................................................................................................. 1
1.1 PURPOSE............................................................................................................................. 1
1.2 MODULE VALIDATION LEVEL ............................................................................................ 1
1.3 REFERENCES....................................................................................................................... 1
1.4 TERMINOLOGY ................................................................................................................... 2
1.5 DOCUMENT ORGANIZATION ............................................................................................... 2
2 CISCO FIPS OBJECT MODULE........................................................................................ 3
3 CRYPTOGRAPHIC MODULE CHARACTERISTICS ................................................... 4
3.1 MODULE INTERFACES......................................................................................................... 5
3.2 ROLES AND SERVICES......................................................................................................... 6
3.3 PHYSICAL SECURITY .......................................................................................................... 7
3.4 CRYPTOGRAPHIC ALGORITHMS .......................................................................................... 7
3.4.1 Approved Cryptographic Algorithms.............................................................. 7
3.4.2 Non-FIPS Approved Algorithms Allowed in FIPS Mode ................................ 8
3.4.3 Non-FIPS Approved Algorithms Not Allowed in FIPS Mode.......................... 8
3.5 CRYPTOGRAPHIC KEY MANAGEMENT................................................................................ 8
3.5.1 Key Generation ............................................................................................. 8
3.5.2 Key Storage................................................................................................... 9
3.5.3 Key Access.................................................................................................... 9
3.5.4 Key Protection and Zeroization ..................................................................... 9
3.6 SELF-TESTS ...................................................................................................................... 11
3.6.1 Self-tests performed .................................................................................... 11
4 SECURE DISTRIBUTION AND OPERATION .............................................................. 13
4.1 SECURE DISTRIBUTION ..................................................................................................... 13
4.2 SECURE OPERATION ......................................................................................................... 13
APPENDIX A – ACRONYMS AND ABBREVIATIONS ...................................................... 14
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1 Introduction
1.1 Purpose
This document is the non-proprietary Cryptographic Module Security Policy for the Cisco FIPS
Object Module (FOM). This security policy describes how the FOM (Software Version: 6.0)
meets the security requirements of FIPS 140-2, and how to operate it in a secure FIPS 140-2
mode. This policy was prepared as part of the Level 1 FIPS 140-2 validation of the Cisco FIPS
Object Module.
FIPS 140-2 (Federal Information Processing Standards Publication 140-2 — Security
Requirements for Cryptographic Modules) details the U.S. Government requirements for
cryptographic modules. More information about the FIPS 140-2 standard and validation program
is available on the NIST website at http://csrc.nist.gov/groups/STM/index.html.
1.2 Module Validation Level
The following table lists the level of validation for each area in the FIPS PUB 140-2.
No. Area Title Level
1 Cryptographic Module Specification 1
2 Cryptographic Module Ports and Interfaces 1
3 Roles, Services, and Authentication 1
4 Finite State Model 1
5 Physical Security N/A
6 Operational Environment 1
7 Cryptographic Key management 1
8 Electromagnetic Interface/Electromagnetic Compatibility 1
9 Self-Tests 1
10 Design Assurance 3
11 Mitigation of Other Attacks N/A
Overall module validation level 1
Table 1 – Module Validation Level
1.3 References
This document deals only with operations and capabilities of the Cisco FIPS Object Module in
the technical terms of a FIPS 140-2 cryptographic module security policy. More information is
available from the following sources:
For answers to technical or sales related questions please refer to the contacts listed on
the Cisco Systems website at www.cisco.com.
The NIST Validated Modules website
(http://csrc.nist.gov/groups/STM/cmvp/validation.html) contains contact information for
answers to technical or sales-related questions for the module.
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1.4 Terminology
In this document, the Cisco FIPS Object Module is referred to as FOM, the library, or the
module.
1.5 Document Organization
The Security Policy document is part of the FIPS 140-2 Submission Package. In addition to this
document, the Submission Package contains:
• Vendor Evidence document
• Finite State Machine
• Other supporting documentation as additional references
This document provides an overview of the Cisco FIPS Object Module and explains the secure
configuration and operation of the module. This introduction section is followed by Section 2,
which details the general features and functionality of the module. Section 3 specifically
addresses the required configuration for the FIPS-mode of operation.
With the exception of this Non-Proprietary Security Policy, the FIPS 140-2 Validation
Submission Documentation is Cisco-proprietary and is releasable only under appropriate non-
disclosure agreements. For access to these documents, please contact Cisco Systems.
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2 Cisco FIPS Object Module
The Cisco FIPS Object Module is a software library that provides cryptographic services to a
vast array of Cisco's networking and collaboration products.
The module provides FIPS 140 validated cryptographic algorithms and KDF functionality for
services such as IPSec (IKE), SRTP, SSH, TLS, and SNMP. The module does not directly
implement any of these protocols, instead it provides the cryptographic primitives and functions
to allow a developer to implement the various protocols. These protocols have not been reviewed
or tested by either the CAVP or the CMVP.
The module is based on the OpenSSL FIPS canister with additions to support Suite B algorithms.
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3 Cryptographic Module Characteristics
Figure 1 – FOM block diagram
The module is a multi-chip standalone cryptographic module. For the purposes of the FIPS 140-2
level 1 validation, the FOM is a single object module file named fipscanister.o (Linux / FreeBSD
Android) or fipscanister.lib (Microsoft Windows). The object code in the object module file is
incorporated into the runtime executable application at the time the binary executable is
generated. The Module performs no communications other than with the consuming application
(the process that invokes the Module services via the Module’s API).
The module’s logical block diagram is shown in Figure 1 above. The dashed red border denotes
the logical cryptographic boundary of the module. The physical cryptographic boundary of the
module is the enclosure of the system on which it is executing and is denoted by the solid black
border.
This module was tested on the following platforms for the purposes of this FIPS validation:
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# Platform
Operating
System Processor
1 Cisco WLC 5508 Linux 2.6 Cavium Octeon MIPS64 (CN5645)
2 Cisco WLC 5508 (build with assembler code) Linux 2.6 Cavium Octeon MIPS64 (CN5645)
3 Google (LG) Nexus 4 Android 4.4 ARM v7 (Qualcomm Snapdragon S4)
4 Gateway FX6860 MS Windows 8.1 Intel Core i7 (i7-2600)
5 Gateway FX6860 MS Windows 8.1 Intel Core i7 (i7-2600) with AES-NI
6 Cisco UCS C200 M2 FreeBSD 9.2 Intel Xeon (Intel 5680)
7 Cisco UCS C22 M3 Linux 2.6 Intel Xeon (Intel E5-2450) with AES-NI
Table 2 – Tested Operational Environments (OEs)
3.1 Module Interfaces
The physical ports of the Module are the same as the system on which it is executing. The logical
interface is a C-language application program interface (API).
The Data Input interface consists of the input parameters of the API functions. The Data Output
interface consists of the output parameters of the API functions. The Control Input interface
consists of the actual API functions. The Status Output interface includes the return values of the
API functions.
The module provides a number of physical and logical interfaces to the application (and the
device upon which it is running), and the physical interfaces provided by the module are mapped
to the following FIPS 140-2 defined logical interfaces: data input, data output, control input,
status output, and power. The logical interfaces and their mapping are described in the following
table:
Interface Description
Data Input API input parameters - plaintext and/or ciphertext data
Data Output API output parameters - plaintext and/or ciphertext data
Control Input API function calls - function calls, or input arguments that specify commands and
control data used to control the operation of the module
Status Output API return codes- function return codes, error codes, or output arguments that
receive status information used to indicate the status of the module
Table 3 – FIPS 140-2 Logical Interfaces
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3.2 Roles and Services
The Module meets all FIPS 140-2 level 1 requirements for Roles and Services, implementing
both Crypto-User and Crypto-Officer roles. As allowed by FIPS 140-2, the Module does not
support user authentication for those roles. Only one role may be active at a time and the Module
does not allow concurrent operators.
The User and Crypto Officer roles are implicitly assumed by the entity accessing services
implemented by the Module. The Crypto Officer can install and initialize the Module. The
Crypto Officer role is implicitly entered when installing the Module or performing system
administration functions on the host operating system.
• User Role: Loading the Module and calling any of the API functions. This role has access
to all of the services provided by the Module.
• Crypto-Officer Role: All of the User Role functionality as well as installation of the
Module on the host computer system. This role is assumed implicitly when the system
administrator installs the Module library file.
The following table lists the approved or non-approved but allowed services available in FIPS
Approved mode.
Service Role CSP Access
Module Installation Crypto Officer None N/A
Symmetric
encryption/decryption
User, Crypto Officer
Symmetric keys AES, Triple-
DES
Execute
Symmetric Digest User, Crypto Officer AES CMAC key Execute
Key transport User, Crypto Officer Asymmetric private key RSA Execute
Key agreement User, Crypto Officer DH and ECDH private key Execute
Digital signature User, Crypto Officer
Asymmetric private key RSA,
DSA, ECDSA
Execute
Key Generation
(Asymmetric)
User, Crypto Officer
Asymmetric keys DSA,
ECDSA, and RSA
Write/execute
Key Generation
(Symmetric)
User, Crypto Officer
Symmetric keys AES, Triple-
DES
Write/execute
Keyed Hash (HMAC) User, Crypto Officer HMAC key Execute
Message digest (SHS) User, Crypto Officer None N/A
Random number
generation
User, Crypto Officer
Seed/entropy input,
V, C, Key, and S
Write/execute
Show status User, Crypto Officer None N/A
Module initialization User, Crypto Officer None N/A
Perform Self-test User, Crypto Officer None N/A
Zeroization User, Crypto Officer All CSPs N/A
Table 4 – Roles, Services, and Keys (Approved Mode)
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The following table lists the non-Approved services available in non-approved mode.
Service Role CSP Access
Key transport using non-Approved
RSA key size
User, Crypto
Officer
Asymmetric private
key RSA
Execute
Key agreement using non-Approved
domain parameters size for Diffie-
Hellman or EC Diffie-Hellman
User, Crypto
Officer
DH and ECDH private
key
Execute
Random number generation (as per
the DRBG defined in SP800-90)
User, Crypto
Officer
Seed/entropy input,
V, C, Key, and S
Write/execute
Digital signature using non-Approved
RSA key size
User, Crypto
Officer
Asymmetric private
key RSA
Execute
Asymmetric Key Generation using
non-Approved RSA key size
User, Crypto
Officer
Asymmetric key RSA Write/execute
Table 5 – Roles, Services, and Keys (Non-Approved Mode)
3.3 Physical Security
The module is comprised of software only and thus does not claim any physical security.
3.4 Cryptographic Algorithms
The module implements a variety of approved and non-approved algorithms.
3.4.1 Approved Cryptographic Algorithms
The FOM supports the following FIPS 140-2 approved algorithm implementations:
Table 6 – Approved Cryptographic Algorithms
It should be noted that the XTS-AES mode, included in the AES algorithm certificates numbers
3404 and 3405 in Table 5, and as defined in NIST SP 800-38E and referred to in “Annex A:
Algorithm Algorithm Certificate Numbers
AES 3404, 3405
CCM 3404, 3405
CVL 504, 505, 506, 507
DRBG 817, 818
DSA 961, 962
ECDSA 678, 679
HMAC 2172, 2173
KBKDF (SP800-108) 52, 53
RSA 1743, 1744
SHS 2817, 2818
Triple-DES 1926, 1927
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Approved Security Functions for FIPS PUB 140-2” ‘Symmetric Key’, Section 1, ‘Advanced
Encryption Standard (AES)’, should only be used for the cryptographic protection of data on
storage devices.
Additionally, it should be noted that per NIST SP 800-131A, through December 31, 2015, the
use of 2-key Triple DES for encryption is restricted: the total number of blocks of data encrypted
with the same cryptographic key shall not be greater than 220
. After December 31, 2015, 2-key
Triple DES shall not be used for encryption. Decryption using 2-key Triple DES is allowed for
legacy-use.
3.4.2 Non-FIPS Approved Algorithms Allowed in FIPS Mode
The module supports the following non-FIPS approved algorithms which are permitted for use in
the FIPS approved mode:
• Diffie-Hellman (key agreement; key establishment methodology provides between 112
and 219 bits of encryption strength)
• EC Diffie-Hellman (key agreement; key establishment methodology provides between
112 and 256 bits of encryption strength)
• RSA (key wrapping; key establishment methodology provides between 112 and 132 bits
of encryption strength)
3.4.3 Non-FIPS Approved Algorithms Not Allowed in FIPS Mode
The module supports the following non-FIPS approved algorithms which are not permitted for
use in the FIPS approved mode:
• Diffie-Hellman (key agreement; key establishment methodology; non-compliant less than
112-bits of encryption strength)
• EC Diffie-Hellman (key agreement; key establishment; non-compliant less than 112-bits
of encryption strength)
• RSA (key wrapping; key establishment; non-compliant less than 112-bits of encryption
strength)
Any use of the non-approved algorithm will cause the module to operate in the non-Approved
mode implicitly.
3.5 Cryptographic Key Management
3.5.1 Key Generation
The Module supports generation of DH, ECDH, DSA, RSA, and FIPS 186-4 ECDSA public-
private key pairs. The Module employs a NIST SP800-90A random number generator for
creation of both symmetric keys and the seed for asymmetric key generation.
The entropy and seeding material for the NDRNG is provided to it by the calling application
(and not by the module) which is outside the module’s logical boundary but contained within the
module’s physical boundary. The minimum effective strength of the DRBG seed is at least 112
bits when used in a FIPS approved mode of operation, therefore the minimum number of bits of
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entropy requested when the module makes a call to the DRBG is 112. The module generates
cryptographic keys whose strengths are modified by available entropy
3.5.2 Key Storage
Public and private keys are provided to the Module by the calling process, and are destroyed
when released by the appropriate API function calls. The Module does not perform persistent
storage of keys.
3.5.3 Key Access
An authorized application as user (the Crypto-User) has access to all key data generated during
the operation of the Module.
3.5.4 Key Protection and Zeroization
Keys residing in internally allocated data structures can only be accessed using the Module
defined API. The operating system protects memory and process space from unauthorized
access. Zeroization of sensitive data is performed automatically by API function calls for
intermediate data items.
Only the process that creates or imports keys can use or export them. No persistent storage of
key data is performed by the Module. All API functions are executed by the invoking process in
a non-overlapping sequence such that no two API functions will execute concurrently.
All CSPs can be zeroized by power-cycling the module (with the exception of the Software
Integrity key). In the event Module power is lost and restored the consuming application must
ensure that any AES-GCM keys used for encryption or decryption are re-distributed.
The module supports the following keys and critical security parameters (CSPs):
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ID Algorithm Size Description
Asymmetric Keys RSA
DSA
ECDSA
RSA: 1,024, 2,048, 3,072 bits
DSA: 1,024, 2,048, 3,072 bits
ECDSA: P-256, P-384, P-521
Used for signature
verification.
RSA: Also used for key
transport (where the size of
the modulus is greater than
or equal to 2048 bits)
Asymmetric Keys RSA
DSA
ECDSA
RSA: 2,048, 3,072 bits
DSA: 2,048, 3,072 bits
ECDSA: P-256, P-384, P-521
Used for signature
generation with SHA-2 used
in key pair generation.
RSA: Also used for key
transport (where the size of
the modulus is greater than
or equal to 2048 bits)
Symmetric Keys AES
Triple-DES
AES: 128, 192, 256 bits
Triple-DES: 128, 192 bits
Used for symmetric
encryption/decryption
Diffie-Hellman/
EC Diffie-Hellman
private key
DH
ECDH
DH: Public Key – 2,048-10,000 bits
Private Key – 224-512 bits
ECDH: P-256, P-384, P-521
Used for key agreement
Hash_DRBG DRBG
(as per
NIST SP
800-90A)
− V (440/888 bits)
− C (440/888 bits)
− entropy input (The length of the
selected hash)
CSPs for Hash_DRBG as per
NIST SP800-90A.
HMAC_DRBG DRBG
(as per
NIST SP
800-90A)
− V (160/224/256/384/512 bits)
− Key (160/224/256/384/512 bits)
− entropy input (The length of the
selected hash)
CSPs for HMAC_DRBG as
per NIST SP800-90A.
CTR_DRBG DRBG
(as per
NIST SP
800-90A)
− V (128 bits)
− Key (AES 128/192/256)
− entropy input (The length of the
selected AES)
CSPs for CTR_DRBG as per
NIST SP800-90A.
Keyed Hash key HMAC All supported key sizes for HMAC
(Key sizes must be a minimum of
112- bits)
Used for keyed hash
Software Integrity
key
HMAC HMAC-SHA-1 Used to perform software
integrity test at power-on.
This key is embedded within
the module.
Table 7 – Cryptographic Keys and CSPs
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3.6 Self-Tests
The Module performs both power-up self-tests at module initialization1
and continuous condition
tests during operation. Input, output, and cryptographic functions cannot be performed while the
Module is in a self-test or error state as the module is single threaded and will not return to the
calling application until the power-up self-tests are complete. If the power-up self- tests fail
subsequent calls to the module will fail and thus no further cryptographic operations are possible.
3.6.1 Self-tests performed
• POST tests
o AES Known Answer Test (Separate encrypt and decrypt)
o AES-CCM Known Answer Test (Separate encrypt and decrypt)
o AES-GCM Known Answer Test (Separate encrypt and decrypt)
o AES-CMAC Known Answer Test
o AES-XTS Known Answer Test (Separate encrypt and decrypt)
o DRBG Known Answer Tests
 HASH_DRBG Known Answer Test
 HMAC_DRBG Known Answer Test
 CTR_DRBG Known Answer Test
o DSA Sign/Verify Test
o FIPS 186-4 ECDSA Sign/Verify Test
o HMAC Known Answer Tests
 HMAC-SHA1 Known Answer Test
 HMAC-SHA224 Known Answer Test
 HMAC-SHA256 Known Answer Test
 HMAC-SHA384 Known Answer Test
 HMAC-SHA512 Known Answer Test
o ECC CDH KAT
o RSA Known Answer Test (Separate sign and verify)
o SHA-1 Known Answer Test
o Software Integrity Test (HMAC-SHA1)
o Triple-DES Known Answer Test (Separate encrypt and decrypt)
• Conditional tests
o Pairwise consistency tests for RSA, DSA, and ECDSA
o Continuous random number generation test for approved DRBG.
• Critical Function Tests (applicable to the DRBG, as per SP800-90A, Section 11)
o Instantiate Test
o Generate Test
1
The FIPS mode initialization is performed prior to the application invoking the FIPS_mode_set() function call
(which returns a “1” for success and “0” for failure). Initialization is performed by an OS Loader on module power
up.
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o Reseed Test
o Uninstantiate Test
A single function call, FIPS_mode_set(), is required to enable the Module for operation in the
FIPS 140-2 Approved mode. When the Module is in FIPS mode all security functions and
cryptographic algorithms are performed in Approved mode.
FIPS mode can only be enabled after the application invokes the FIPS_mode_set() call which
returns a “1” for success and “0” for failure. Interpretation of this return code is the responsibility
of the host application. Prior to this invocation the Module has already gone through its
initialization sequence.
The FIPS_mode_set() function checks that the initialization sequence and POSTs (performed by
the OS Loader at module power-up) have completed successfully. The initialization sequence
starts with a check of the integrity of the runtime executable using a HMAC-SHA-1 digest
computed at build time. If this computed HMAC-SHA-1 digest matches the stored known digest
then the power-up self-tests, consisting of the algorithm specific Pairwise Consistency and
Known Answer tests, are performed. If any component of the power-up self-test fails an internal
global error flag is set to prevent subsequent invocation of any cryptographic function calls. Any
such power-up self-test failure is a hard error that can only be recovered by reinstalling the
Module2
. If all components of the power-up self-test are successful then the Module is in FIPS
mode. This function call also returns a “1” for success and “0” for failure, and interpretation of
this return code is the responsibility of the host application.
2
The FIPS_mode_set() function could be re-invoked but such re-invocation does not provide a means of recovering
from an integrity test or known answer test failure.
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4 Secure Distribution and Operation
4.1 Secure Distribution
The Cisco FOM is intended only for use by Cisco personnel and as such is accessible only from
the secure Cisco internal web site. Only authorized employees have access to the module.
4.2 Secure Operation
The tested operating systems segregate user processes into separate process spaces. Each process
space is an independent virtual memory area that is logically separated from all other processes
by the operating system software and hardware. The Module functions entirely within the
process space of the process that invokes it, and thus satisfies the FIPS 140-2 requirement for a
single user mode of operation.
The module is installed using one of the set of instructions in the ‘CiscoSSL 6.0 FIPS
Compliance Guide’ document appropriate to the target system. A complete revision history of
the source code from which the Module was generated is maintained in a version control
database3
. The HMAC-SHA-1 of the Module distribution file as tested by the CSTL Laboratory
is verified during installation of the Module file as described in the ‘CiscoSSL 6.0 FIPS
Compliance Guide’ document.
The HMAC fingerprint of the validated distribution file is:
a8b02b2531ecf9cb649865c61fc83d2cffe9a023
Upon initialization of the Module by the OS loader directly after Module power-up, the power-
up self-tests will execute. Successful completion of the power-up self- tests ensures that the
module is operating in the FIPS mode of operation.
The self-tests are called when initializing the module, or alternatively using the FIPS_selftest()
function call.
3
This database is internal to Cisco since the intended use of this crypto module is by Cisco development teams.
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Appendix A – Acronyms and Abbreviations
Term Expansion / Definition
AES Advanced Encryption Standard
API Application Program Interface
CCM Counter with Cipher Block Chaining-Message Authentication Code
CMVP Cryptographic Module Validation Program
CSE Communications Security Establishment
CSP Critical Security Parameter
CVL Component Validation List
DES Data Encryption Standard
DH Diffie-Hellman
DRBG Deterministic Random Bit Generator
DSA Digital Signature Algorithm
ECDH Elliptic Curve Diffie-Hellman
ECDSA Elliptic Curve Digital Signature Algorithm
FIPS Federal Information Processing Standard
FOM FIPS Object Module
GCM Galois/Counter Mode
HMAC Hash Message Authentication Code
HTTP Hyper Text Transfer Protocol
IKE Internet Key Exchange
IPSec Internet Protocol Security
KAT Known Answer Test
KBKDF Key Based Key Derivation Function
KDF Key Derivation Function
MAC Message Authentication Code
MS Microsoft
NIST National Institute of Standards and Technology
OS Operating System
POST Power-On Self-Test
RSA Rivest Shamir and Adleman
SHA Secure Hash Algorithm
SHS Secure Hash Standard
SNMP Simple Network Management Protocol
SP Special Publication
SRTP Secure Real-time Transport Protocol
SSH Secure Shell
TLS Transport Layer Security
XEX XOR Encrypt XOR
XOR Exclusive OR
XTS XEX Tweakable Block Cipher with Ciphertext Stealing