Configuring FIPS Mode

The Federal Information Processing Standard (FIPS) 140-2 is an U.S. and Canadian government certification standard that defines requirements that the cryptographic modules must follow. The FIPS specifies best practices for implementing cryptographic algorithms, handling key material and data buffers, and working with the operating system.

In Cisco IOS XR software, these applications are verified for FIPS compliance:

  • Secure Shell (SSH)

  • Secure Socket Layer (SSL)

  • Transport Layer Security (TLS)

  • Internet Protocol Security (IPSec) for Open Shortest Path First version 3 (OSPFv3)

  • Simple Network Management Protocol version 3 (SNMPv3)

  • AAA Password Security


Note

Any process that uses any of the following cryptographic algorithms is considered non-FIPS compliant:

  • Rivest Cipher 4 (RC4)

  • Message Digest (MD5)

  • Keyed-Hash Message Authentication Code (HMAC) MD5

  • Data Encryption Standard (DES)

The Cisco Common Cryptographic Module (C3M) provides cryptographic services to a wide range of the networking and collaboration products of Cisco. This module provides FIPS-validated cryptographic algorithms for services such as RTP, SSH, TLS, 802.1x, and so on. The C3M provides cryptographic primitives and functions for the users to develop any protocol.

By integrating with C3M, the Cisco IOS-XR software is compliant with the FIPS 140-2 standards and can operate in FIPS mode, level 1 compliance.

Prerequisites for Configuring FIPS

You must be in a user group associated with a task group that includes the proper task IDs. The command reference guides include the task IDs required for each command.

If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Guidelines for Enabling FIPS Mode

From Cisco IOS XR Software Release 7.2.1 and later, you must follow these guidelines while enabling FIPS mode:

  • You must configure the session with a FIPS-approved cryptographic algorithm. A session configured with non-approved cryptographic algorithm for FIPS (such as, MD5 and HMAC-MD5 ) does not work. This is applicable for OSPF, BGP, RSVP, ISIS, or any application using key chain with non-approved cryptographic algorithm, and only for FIPS mode (that is, when crypto fips-mode is configured).

  • If you are using any HMAC-SHA algorithm for a session, then you must ensure that the configured key-string has a minimum length of 14 characters. Otherwise, the session goes down. This is applicable only for FIPS mode.

  • If you try to execute the telnet configuration on a system where the FIPS mode is already enabled, then the system rejects the telnet configuration.

  • If telnet configuration already exists on the system, and if FIPS mode is enabled later, then the system rejects the telnet connection. But, it does not affect the telnet configuration as such.

  • It is recommended to configure the crypto fips-mode command first, followed by the commands related to FIPS in a separate commit. The list of commands related to FIPS with non-approved cryptographic algorithms are:

    • key chain key-chain-name key key-id cryptographic-algorithm MD5

    • key chain key-chain-name key key-id cryptographic-algorithm HMAC-MD5

    • router ospfv3 1 authentication ipsec spi 256 md5 test-md5-value

    • router ospfv3 1 encryption ipsec spi 256 esp des test-des-value

    • router ospfv3 1 encryption ipsec spi 256 esp des test-des-value authentication md5 test-md5-value

    • snmp-server user user1 user-grp1 v3 auth md5 priv des56

    • ssh server algorithms key-exchange diffie-hellman-group1-sha1

    • telnet vrf default ipv4 server max-servers 100

How to Configure FIPS

Perform these tasks to configure FIPS.

Enable FIPS mode

Procedure

Step 1

configure

Example:


RP/0/RP0/CPU0:router# configure

Enters mode.

Step 2

crypto fips-mode

Example:

 
Router(config)#crypto fips-mode

Enters FIPS configuration mode.

Note

 

Stop new incoming SSH sessions while configuring or unconfiguring crypto fips-mode . Restart the router upon configuration.

Step 3

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.

Step 4

show logging

Example:


Router#show logging
Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
    Console logging: level debugging, 60 messages logged
    Monitor logging: level debugging, 0 messages logged
    Trap logging: level informational, 0 messages logged
    Buffer logging: level debugging, 3 messages logged
 
Log Buffer (9000000 bytes):
<output omitted>
 
Log Buffer (307200 bytes):

RP/0/RSP0/CPU0:Apr 16 12:48:17.736 : cepki[433]: The configuration setting for FIPS mode has been modified. The system must be reloaded to finalize this configuration change. Please refer to the IOS XR System Security Configuration Guide, Federal Information Process Standard(FIPS) Overview section when modifying the FIPS mode setting. 
RP/0/RSP0/CPU0:Apr 16 12:48:17.951 : config[65757]: %MGBL-CONFIG-6-DB_COMMIT :
Configuration committed by user 'lab'. Use 'show configuration commit changes 1000000002' to view the changes. 
RP/0/RSP0/CPU0:Apr 16 12:48:23.988 : config[65757]: %MGBL-SYS-5-CONFIG_I : Configured from console by lab 


....
....
....

Displays the contents of logging buffers.

Note

 
Use the show logging | i fips command to filter FIPS specific logging messages.

Step 5

reload location all

Example:

 
Router#reload location all

Reloads a node or all nodes on a single chassis or multishelf system.

Configure FIPS-compliant Keys

Perform these steps to configure the FIPS-compliant keys:


Note

The crypto keys are auto-generated at the time of router boot up. You need to perform these steps to generate the keys only if the keys are missing under some scenarios.


Note

From Cisco IOS XR Release 7.3.2 onwards, you can generate and delete key-pairs from XR Config mode. For more details, see Public Key-Pair Generation in XR Config Mode in the chapter Implementing Certification Authority Interoperability .

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

crypto key generate rsa [usage-keys | general-keys] key label

Example:

 Router#crypto key generate rsa general-keys rsakeypair

Generate a RSA key pair. Ensure that all the key pairs meet the FIPS requirements. The RSA key sizes allowed under FIPS mode are 2048, 3072 and 4096.

The option usage-keys generates separate RSA key pairs for signing and encryption. The option general-keys generates a general-purpose RSA key pair for signing and encryption.

To delete the RSA key pair, use the crypto key zeroize rsa keypair-label command.

Step 2

crypto key generate dsa

Example:

 Router#crypto key generate dsa

Generate a DSA key pair if required. Ensure that all the key pairs meet the FIPS requirements. The DSA key size allowed under FIPS mode is 2048.

To delete the DSA key pair, use the crypto key zeroize dsa keypair-label command.

Step 3

crypto key generate ecdsa

Example:

 Router#crypto key generate ecdsa

Generate a ECDSA key pair if required. Ensure that all the key pairs meet the FIPS requirements. The ECDSA key sizes allowed under FIPS mode are nistp256 , nistp384 and nistp512 .

To delete the DSA key pair, use the crypto key zeroize ecdsa keypair-label command.

Step 4

show crypto key mypubkey rsa

Example:

Router# show crypto key mypubkey rsa
Fri Mar 27 14:00:20.954 IST
Key label: system-root-key
Type : RSA General purpose
Size : 2048
Created : 01:13:10 IST Thu Feb 06 2020
Data :
 30820122 300D0609 2A864886 F70D0101 01050003 82010F00 3082010A 02820101
 00A93DE0 1E485EE3 0E7F0964 C48361D1 B6014BE7 A303D8D6 F7790E92 88E69C4B
 B97B7A9C D1B277E3 1569093C 82BD3258 7F67FB49 94860ECD 34498F1F 59B45757
 F32C8E8F 7CEE23EC C36A43D1 9F85C0D9 B96A14DD DD3BBD4C A1FB0888 EED210A7
 39D9A403 7ACE0F6E 39107226 CA621AD8 6E8102CA 9761B86F D33F2871 9DD16559
 AFCB4729 EFCEDBAF 83DF76E4 9A439844 EE3B1180 4022F575 99E11A2C E25BB23D
 9DD74C81 4E5C1345 D9E3CC79 1B98B1AA 6C06F004 22B901EC 36C099FE 10DE2622
 EB7CE618 9A555769 12D94C90 D9BEE5EA A664E7F6 4DF8D8D4 FE7EAB07 1EF4FEAB
 22D9E55F 62BA66A0 72153CEC 81F2639F B5F2B5C5 25E10364 19387C6B E8DB8990
 11020301 0001
Key label: system-enroll-key
Type : RSA General purpose
Size : 2048
Created : 01:13:16 IST Thu Feb 06 2020
Data :
 30820122 300D0609 2A864886 F70D0101 01050003 82010F00 3082010A 02820101
 009DBC14 C83604E4 EB3D3CF8 5BA7FDDB 80F7E85B 427332D8 BBF80148 F0A9C281
 49F87D5C 0CEBA532 EBE797C5 7F174C69 0735D13A 493670CB 63B04A12 4BCA7134
 EE0031E9 047CAA1E 802030C5 6071E8C2 F8ECE002 CC3B54E7 5FD24E5C 61B7B7B0
 68FA2EFA 0B83799F 77AE4621 435D9DFF 1D713108 37B614D3 255020F9 09CD32E8
 82B07CD7 01A53896 6DD92B5D 5119597C 98D394E9 DBD1ABAF 6DE949FE 4A8BF1E7
 851EB3F4 60B1114A 1456723E 063E50C4 2D410906 BDB7590B F1D58480 F3FA911A
 6C9CD02A 58E68D04 E94C098F 0F0E81DB 76B40C55 64603499 2AC0547A D652412A
 BCBBF69F 76B351EE 9B2DF79D E490C0F6 92D1BB97 B905F33B FAB53C20 DDE2BB22
 C7020301 0001

Displays the existing RSA key pairs.

Step 5

show crypto key mypubkey dsa

Example:

 Router#show crypto key mypubkey dsa

Displays the existing DSA key pairs.

Configure FIPS-compliant Key Chain

Perform these steps to configure the FIPS-compliant key chain:

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

configure

Example:

 Router#configure

Enters the global configuration mode.

Step 2

key chain key-chain-name

Example:

 Router(config)#key chain mykeychain

Creates a key chain.

Step 3

key key-id

Example:

 Router(config-mykeychain)#key 1

Creates a key in the key chain.

Step 4

cryptographic-algorithm { HMAC-SHA1-20 | SHA-1}

Example:

 Router(config-mykeychain-1)#cryptographic-algorithm HMAC-SHA1-20

Configures the cryptographic algorithm for the key chain. Ensure that the key chain configuration always uses SHA-1 as the hash or keyed hash message authentication code (hmac) algorithm.

Step 5

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.

Configure FIPS-compliant Certificates

Perform these steps to configure the FIPS-compliant certificates:

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

configure

Example:


RP/0/RP0/CPU0:router# configure

Enters mode.

Step 2

crypto ca trustpoint ca-name key label

Example:

 Router(config)#crypto ca trustpoint msiox rsakeypair

Configures the trustpoint by utilizing the desired RSA keys.

Ensure that the certificates meet the FIPS requirements for key length and signature hash or encryption type.

Note

 

The minimum key length for RSA or DSA key is 1024 bits. The required hash algorithm is SHA-1-20.

Step 3

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.

Step 4

show crypto ca certificates

Example:

 Router#show crypto ca certificates

Displays the information about the certificate

What to do next

For more information about certification authority and requesting router certificates, see the Implementing Certification Authority chapter in this guide.

Configure FIPS-compliant OSPFv3

Perform these steps to configure the FIPS-compliant OSPFv3:

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

configure

Example:


RP/0/RP0/CPU0:router# configure

Enters mode.

Step 2

router ospfv3 process name

Example:

 Router(config)#router ospfv3 ospfname

Configures the OSPFv3 process.

Step 3

area id

Example:

 Router(config-ospfv3)#area 1

Configures the OSPFv3 area ID. The ID can either be a decimal value or an IP address.

Step 4

authentication{ disable | ipsec spi spi-value sha1 [ clear | password] password}

Example:

 Router(config-ospfv3-ar)#authentication ipsec spi 256 sha1 password pa1

Enables authentication for OSPFv3. Note that the OSPFv3 configuration supports only SHA-1 for authentication.

Note

 

IPSec is supported only for Open Shortest Path First version 3 (OSPFv3).

Step 5

exit

Example:

 Router(config-ospfv3-ar)#exit

Exits OSPFv3 area configuration and enters the OSPFv3 configuration mode.

Step 6

encryption{ disable | { ipsec spi spi-value esp { 3des | aes [ 192 | 256] [ clear | password] encrypt-password} [ authentication sha1[ clear | password] auth-password] } }

Example:

 Router(config-ospfv3)#encryption ipsec spi 256 esp 3des password pwd
Encrypts and authenticates the OSPFv3 packets. Ensure that the OSPFv3 configuration uses the following for encryption in the configuration.

  • 3DES: Specifies the triple DES algorithm.

  • AES: Specifies the Advanced Encryption Standard (AES) algorithm.

Ensure that SHA1 is chosen if the authentication option is specified.

Step 7

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.

Configure FIPS-compliant SNMPv3 Server

Perform these steps to configure the FIPS-compliant SNMPv3 server:

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

configure

Example:

 Router#configure

Enters the global configuration mode.

Step 2

snmp-server user username groupname { v3 [ auth sha { clear | encrypted} auth-password [ priv { 3des | aes { 128 | 192 | 256} } { clear | encrypted } priv-password] ] } [ SDROwner | SystemOwner] access-list-name

Example:

 Router(config)#snmp-server user user1 g v3 auth sha clear pass priv aes 128 clear privp

Configures the SNMPv3 server.

Step 3

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.

Configure FIPS-compliant SSH Client and Server

Perform these steps to configure the FIPS-compliant SSH Client and the Server:

Before you begin

Refer the configuration steps in the Enable FIPS mode section for enabling the FIPS mode.

Procedure

Step 1

ssh { ipv4-address | ipv6-address} cipher aes { 128-CTR | 192-CTR | 256-CTR} username username

Example:

 Router#ssh 192.0.2.1 cipher aes 128-CTR username user1

Starts an SSH session to the server using the FIPS-approved ciphers. Ensure that the SSH client is configured only with the FIPS-approved ciphers. AES(Advanced Encryption Standard)-CTR (Counter mode) is the FIPS-compliant cipher algorithm with key lengths of 128, 192 and 256 bits.

Step 2

configure

Example:


RP/0/RP0/CPU0:router# configure

Enters mode.

Step 3

ssh server v2

Example:

 Router(config)#ssh server v2

Configures the SSH server.

The supported key exchange algorithms are:

  • diffie-hellman-group14-sha1

  • ecdh-sha2-nistp256

  • ecdh-sha2-nistp384

  • ecdh-sha2-nistp521

The supported cipher algorithms are:

  • aes128-ctr

  • aes192-ctr

  • aes256-ctr

  • aes128-gcm

  • aes256-gcm

The supported HMAC algorithms are:

  • hmac-sha2-512

  • hmac-sha2-256

  • hmac-sha1

Step 4

Use the commit or end command.

commit —Saves the configuration changes and remains within the configuration session.

end —Prompts user to take one of these actions:

  • Yes — Saves configuration changes and exits the configuration session.

  • No —Exits the configuration session without committing the configuration changes.

  • Cancel —Remains in the configuration session, without committing the configuration changes.